Propensity Score Methods: Theory and Practice for Anesthesia Research

Modified frailty index effectively predicts adverse outcomes in sepsis patients in the intensive care unit

BACKGROUND

Frailty and sepsis have a significant impact on patient prognosis. However, research into the relationship between frailty and sepsis in the general adult population remains inadequate. This paper aims to investigate the association between frailty and adverse outcomes in this population.

METHOD

This retrospective analysis investigated sepsis patients who were initially admitted to the intensive care unit (ICU). The Modified Frailty Index (MFI) was derived by tracking patients' International Classification of Diseases (ICD) codes during their hospitalization. Patients were classified into two groups based on their MFI scores: a frail group (MFI ≥ 3) and a non-frail group (MFI = 0-2). The key outcomes were mortality rates at 90 and 180 days, with secondary outcomes including the incidence of delirium and pressure injury.

RESULT

Of the 21,338 patients who were recruited for this study (median age about 68 years, 41.8 % female), 5,507 were classified as frail and 15,831 were classified as non-frail. Frail patients were significantly more likely to have delirium (48.9 % vs. 36.1 %, p < 0.001) and pressure injury (60.5 % vs. 51.4 %, p < 0.001). After controlling for confounding variables, the multifactorial Cox proportional hazard regression analyses revealed a significantly elevated mortality rate at 90 days (adjusted HR: 1.58, 95 % CI: 1.24-2.02, p < 0.001) and 180 days (adjusted HR: 1.47, 95 % CI: 1.18, 1.83, p < 0.001) in the frail group compared to their non-frail counterparts.

CONCLUSIONS

Frailty independently predisposes adult sepsis patients in the ICU to adverse outcomes. Future investigations should concentrate on evaluating frailty and developing targeted interventions to improve patient prognosis.

IMPLICATION FOR CLINICAL PRACTICE

The MFI provides a simple clinical assessment tool that can be integrated into electronic medical records for immediate calculation. This simplifies the assessment process and plays a key role in predicting patient outcomes.

Association between intraoperative tidal volume and postoperative acute kidney injury in non-cardiac surgical patients using a propensity score-weighted analysis

Acute kidney injury (AKI) is related to adverse clinical outcomes. Therefore, identifying patients at increased risk of postoperative AKI and proactively providing appropriate care is crucial. However, only a limited number of modifiable risk factors have been recognized to mitigate AKI risk. We retrospectively analyzed adult patients who underwent endotracheal intubation and mechanical ventilation of more than 2 h during non-cardiac surgery at Seoul National University Hospital from January 2011 to November 2022. Patients were grouped into low- or high-tidal volume groups based on their intraoperative tidal volume relative to their predicted body weight (PBW) of 8 ml/kg. The association between intraoperative tidal volume and postoperative AKI was evaluated using inverse probability of treatment weighting (IPTW), adjusting for various preoperative confounders. Among the 37,726 patients included, the incidence of postoperative AKI was 4.1%. The odds of postoperative AKI risk were significantly higher in the high-tidal volume group than in the low-tidal volume group before and after IPTW (odds ratio [OR] 1.20, 95% confidence interval [CI] 1.08-1.32, P = 0.001 and OR: 1.10, 95% CI 1.02-1.19, P = 0.010, respectively). In the multivariable logistic regression analysis after IPTW, a high tidal volume was independently associated with an increased risk of postoperative AKI (OR: 1.21, 95% CI 1.12-1.30, P < 0.001). In this propensity score-weighted analysis, an intraoperative high tidal volume of more than 8 ml/kg PBW was significantly associated with an increased risk of postoperative AKI after IPTW in non-cardiac surgical patients. Intraoperative tidal volume showed potential as a modifiable risk factor for preventing postoperative AKI.

Association of Quantity and Diversity of Different Types of Fruit Intake with New-Onset Kidney Stones

SCOPE

This study aims to assess the association between intake of different types of fruit (citrus, pomes, tropical fruits, berries, gourds, drupes, dried fruits, and other fruits), the intake diversity of fruit types, and risk of new-onset kidney stones in general population.

METHODS AND RESULTS

A total of 205 896 participants with at least one completed 24-h dietary recall from the UK Biobank are included. During a median follow-up of 11.6 years, 2074 cases of kidney stones are documented. Compared with nonconsumers, participants with higher intake of citrus (50-<100 g day-1; hazards ratio [HR] = 0.78; 95% confidence interval [CI], 0.66-0.91; ≥100 g day-1; HR = 0.75; 95%CI, 0.63-0.89), pomes (≥100 g day-1; HR = 0.86; 95%CI, 0.77-0.96), or tropical fruits (50-<100 g day-1; HR = 0.86; 95%CI, 0.75-0.99; ≥100 g day-1; HR = 0.88; 95%CI, 0.79-0.99) have a lower risk of new-onset kidney stones. However, there is no significant association of intake of berries, gourds, drupes, dried fruits, and other fruits with kidney stones. A higher fruit variety score is significantly associated with a lower risk of new-onset kidney stones (per 1-score increment, HR = 0.86; 95%CI, 0.81-0.91).

CONCLUSIONS

Higher intake of citruses (≥50 g day-1), pomes (≥100 g day-1), and tropical fruits (≥50 g day-1), as well as increasing diversity of intake of these three fruits, are associated with a lower risk of new-onset kidney stones.

Early postoperative fever as a predictor of pancreatic fistula after pancreaticoduodenectomy: a single-center retrospective observational study

BACKGROUND

The connection between early postoperative fever and clinically relevant postoperative pancreatic fistula (CR-POPF) after pancreaticoduodenectomy remains unclear. This study aimed to investigate this association and assess the predictive value of early postoperative fever for CR-POPF.

METHODS

This retrospective observational study included adult patients who underwent pancreaticoduodenectomy at a tertiary teaching hospital between 2007 and 2019. Patients were categorized into those with early postoperative fever (≥ 38 °C in the first 48 h after surgery) and those without early postoperative fever groups. Weighted logistic regression analysis using stabilized inverse probability of treatment weighting (sIPTW) and multivariable logistic analysis were performed. The c-statistics of the receiver operating characteristic curves were calculated to evaluate the impact on the predictive power of adding early postoperative fever to previously identified predictors of CR-POPF.

RESULTS

Of the 1997 patients analyzed, 909 (45.1%) developed early postoperative fever. The overall incidence of CR-POPF among all the patients was 14.3%, with an incidence of 19.5% in the early postoperative fever group and 9.9% in the group without early postoperative fever. Early postoperative fever was significantly associated with a higher risk of CR-POPF after sIPTW (adjusted odds ratio [OR], 1.73; 95% confidence interval [CI], 1.34-2.22; P < 0.001) and multivariable logistic regression analysis (adjusted OR, 1.88; 95% CI, 1.42-2.49; P < 0.001). The c-statistics for the models with and without early postoperative fever were 0.76 (95% CI, 0.73-0.79) and 0.75 (95% CI, 0.72-0.78), respectively, showing a significant difference between the two (difference, 0.02; 95% CI, 0.00-0.03; DeLong's test, P = 0.005).

CONCLUSIONS

Early postoperative fever is a significant but not highly discriminative predictor of CR-POPF after pancreaticoduodenectomy. However, its widespread occurrence limits its applicability as a predictive marker.

The association between preoperative multidisciplinary team care and patient outcome in frail patients undergoing cardiac surgery

OBJECTIVE

To evaluate the influence of preoperative multidisciplinary team (MDT) care on perioperative management and outcomes of frail patients undergoing cardiac surgery.

BACKGROUND

Frail patients are at increased risk for complications and poor functional outcome after cardiac surgery. In these patients, preoperative MDT care may improve outcomes.

METHODS

Between 2018 and 2021, 1168 patients aged 70 years or older were scheduled for cardiac surgery, of whom 98 (8.4%) frail patients were referred for MDT care. The MDT discussed surgical risk, prehabilitation, and alternative treatment. Outcomes of MDT patients were compared with 183 frail patients (non-MDT group) from a historical study cohort (2015-2017). Inverse probability of treatment weighting was used to minimize bias from nonrandom allocation of MDT versus non-MDT care. Outcomes were severe postoperative complications, total days in hospital after 120 days, disability, and health-related quality of life after 120 days.

RESULTS

This study included 281 patients (98 MDT and 183 non-MDT patients). Of the MDT patients, 67 (68%) had open surgery, 21 (21%) underwent minimally invasive procedures, and 10 (10%) received conservative treatment. In the non-MDT group, all patients had open surgery. Fourteen (14%) MDT patients experienced a severe complication versus 42 (23%) non-MDT patients (adjusted relative risk, 0.76; 95% CI, 0.51-0.99). Adjusted total days in hospital after 120 days was 8 days (interquartile range, 3-12 days) versus 11 days (interquartile range, 7-16 days) for MDT and non-MDT patients, respectively (P = .01). There was no difference in disability or health-related quality of life.

CONCLUSIONS

Preoperative MDT care for frail patients undergoing cardiac surgery is associated with alterations in surgical management and with a lower risk for severe complications.

Real-World Effectiveness of a Third Dose of mRNA-1273 Versus BNT162b2 on Inpatient and Medically Attended COVID-19 Among Immunocompromised US Adults

INTRODUCTION

Recent data have shown elevated infection rates in several subpopulations at risk of SARS-CoV-2 infection and COVID-19, including immunocompromised (IC) individuals. Previous research suggests that IC persons have reduced risks of hospitalization and medically attended COVID-19 with two doses of mRNA-1273 (SpikeVax; Moderna) compared to two doses of BNT162b2 (Comirnaty; Pfizer/BioNTech). The main objective of this retrospective cohort study was to compare real-world effectiveness of third doses of mRNA-1273 versus BNT162b2 at multiple time points on occurrence of COVID-19 hospitalization and medically attended COVID-19 among IC adults in the United States (US).

METHODS

This retrospective, observational comparative effectiveness study identified patients from the US HealthVerity database from December 11, 2020, through August 31, 2022. Medically attended SARS-CoV-2 infections and hospitalizations were assessed following a three-dose mRNA-1273 versus BNT162b2 regimen. Inverse probability weighting was applied to balance baseline confounders between vaccine groups. Relative risk (RR) and risk difference were calculated for subgroup and sensitivity analyses using a non-parametric method.

RESULTS

In propensity score-adjusted analyses, receiving mRNA-1273 vs. BNT162b2 as third dose was associated with 32.4% (relative risk 0.676; 95% confidence interval 0.506-0.887), 29.3% (0.707; 0.573-0.858), and 23.4% (0.766; 0.626-0.927) lower risk of COVID-19 hospitalization after 90, 180, and 270 days, respectively. Corresponding reductions in medically attended COVID-19 were 8.4% (0.916; 0.860-0.976), 6.4% (0.936; 0.895-0.978), and 2.4% (0.976; 0.935-1.017), respectively.

CONCLUSIONS

Our findings suggest a third dose of mRNA-1273 is more effective than a third dose of BNT162b2 in preventing COVID-19 hospitalization and breakthrough medically attended COVID-19 among IC adults in the US.

Timing of Intraoperative Transitions of Care Among Anesthesiologists Is Not Associated With Postoperative Adverse Outcomes: Retrospective Cohort Study

BACKGROUND

The majority of published research suggests that anesthesia handovers during major surgical procedures are associated with unintended harmful consequences. It is still unclear if the number or quality of the transition of care is the main driver of the adverse outcomes. There is even less data if the timing of the anesthesiologist handovers during the critical portion of the anesthetic continuum (induction or emergence versus surgical period) plays a role in patient outcomes. Therefore, we investigated if the anesthesiologist handovers during induction and emergence are associated with adverse patient outcomes.

METHODS

This retrospective investigation included noncardiac surgical procedures occurring between January 1, 2012 and December 31, 2019 that had exactly 1 attending anesthesiologist handover. We categorized transitions of care between attending anesthesiologists as being before incision, between incision and closing, and after closing. Our primary outcome was a composite of 6 categories of surgical complications and in-hospital mortality. We created logistic generalized estimating equation models to estimate the average relative effect odds ratio between each pair of the 3 transition timing groups across the components of the composite outcome. Inverse probability of treatment weights were used to mitigate confounding on a host of baseline variables. We used Bonferroni correction to adjust for multiple comparisons between the transition groups.

RESULTS

In total, we studied 36,937 procedures with exactly 1 attending anesthesiologist handover. Of these records, 4370 had the transition during induction, 24,999 between incision and closure, and 7568 during emergence. No differences were found between the transition periods and the composite outcome. The estimated average relative effect odds ratio (98.3% confidence interval [CI]) across the components of the composite outcome was as follows: (1.0002 [0.81-1.24], P = .99) between the induction and surgical period; (1.10 [0.87-1.40], P = .32) between the induction and emergence periods; and (0.91 [0.79-1.04], P = .08) between the emergence and surgical periods.

CONCLUSIONS

Timing of intraoperative handover among attending anesthesiologists during noncardiac surgery is not associated with adverse patient outcomes.

Association between postoperative hyperactive delirium and major complications in elderly patients undergoing emergency hip fracture surgery: A large-scale cohort study

AIM

This cohort study aimed to explore the connection between postoperative hyperactive delirium and major complications in elderly patients undergoing emergency hip fracture surgery.

METHODS

Elderly patients aged 65 years and older undergoing emergency hip fracture surgery were included in the study. The presence of postoperative hyperactive delirium was assessed, and logistic regression analysis, following propensity score matching, was conducted to investigate the association between postoperative hyperactive delirium and major complications occurring 30 and 90 days post-surgery. The analysis controlled for potential confounding factors.

RESULTS

After propensity score matching, the analysis included 13 590 patients, equally distributed with 6795 in each group. The group experiencing postoperative hyperactive delirium exhibited a significantly elevated risk of 30-day postoperative complications, including acute renal failure, pneumonia, septicemia, and stroke, with adjusted odds ratios ranging from 1.64 to 2.39. Furthermore, this group displayed notably higher rates of 90-day postoperative complications, encompassing mortality, acute renal failure, pneumonia, septicemia, and stroke, with a significantly increased incidence of mortality within 90 days.

CONCLUSION

Postoperative hyperactive delirium in elderly patients undergoing emergency hip fracture surgery is significantly linked to an increased risk of major complications at both 30 and 90 days post-surgery. These findings underscore the critical importance of delirium prevention and management in this patient population, offering the potential to reduce the occurrence of postoperative complications. Geriatr Gerontol Int 2024; 24: 730-736.

Effect of Propofol Infusion on Need for Rescue Antiemetics in Postanesthesia Care Unit After Volatile Anesthesia: A Retrospective Cohort Study

BACKGROUND

Postoperative nausea and vomiting (PONV) are frequent after volatile anesthesia. We hypothesized that coadministration of propofol with volatile anesthetic compared to pure volatile anesthetics would decrease the need for postoperative antiemetic treatments and shorten recovery time in the postanesthesia care unit (PACU).

METHODS

We retrospectively identified adult patients who underwent procedures using general anesthesia with volatile agents, with or without propofol infusion, from May 2018 through December 2020, and who were admitted to the PACU. Inverse probability of treatment weighting (IPTW) analysis was performed using generalized estimating equations with robust variance estimates to assess whether propofol was associated with decreased need for rescue antiemetics.

RESULTS

Among 47,847 patients, overall IPTW rescue antiemetic use was 4.7% for 17,573 patients who received propofol and 8.2% for 30,274 who did not (odds ratio [OR], 0.55; 95% confidence interval [CI], 0.49-0.61; P <.001). This effect associated with propofol was present regardless of the intensity of antiemetic prophylaxis (OR, 0.59, 0.51, and 0.58 for 0-1, 2, and ≥3 antiemetics used, respectively), procedural duration (OR, 0.54, 0.62, and 0.47 for ≤2.50, 2.51-4.00, ≥4.01 hours), and type of volatile agent (OR, 0.51, 0.52, and 0.57 for desflurane, isoflurane, and sevoflurane) (all P <.001). This effect was dose dependent, with little additional benefit for the reduction in the use of PACU antiemetics when propofol rate exceeded 100 μg/kg/min. Patients who received rescue antiemetics required longer PACU recovery time than those who did not receive antiemetics (ratio of the geometric mean, 1.31; 95% CI, 1.28-1.33; P <.001), but use of propofol did not affect PACU recovery time (ratio of the geometric mean, 1.00; 95% CI, 0.98-1.01; P =.56).

CONCLUSIONS

The addition of propofol infusions to volatile-based anesthesia is associated with a dose-dependent reduction in the need for rescue antiemetics in the PACU regardless of the number of prophylactic antiemetics, duration of procedure, and type of volatile agent used, without affecting PACU recovery time.

Randomized Placebo-Controlled Trial of 60-Day Percutaneous Peripheral Nerve Stimulation Treatment Indicates Relief of Persistent Postoperative Pain, and Improved Function After Knee Replacement

OBJECTIVES

Total knee arthroplasty (TKA) is an effective surgery for end-stage knee osteoarthritis, but chronic postoperative pain and reduced function affect up to 20% of patients who undergo such surgery. There are limited treatment options, but percutaneous peripheral nerve stimulation (PNS) is a promising nonopioid treatment option for chronic, persistent postoperative pain. The objective of the present study was to evaluate the effect of a 60-day percutaneous PNS treatment in a multicenter, randomized, double-blind, placebo-controlled trial for treating persistent postoperative pain after TKA.

MATERIALS AND METHODS

Patients with postoperative pain after knee replacement were screened for this postmarket, institutional review board-approved, prospectively registered (NCT04341948) trial. Subjects were randomized to receive either active PNS or placebo (sham) stimulation. Subjects and a designated evaluator were blinded to group assignments. Subjects in both groups underwent ultrasound-guided placement of percutaneous fine-wire coiled leads targeting the femoral and sciatic nerves on the leg with postoperative pain. Leads were indwelling for eight weeks, and the primary efficacy outcome compared the proportion of subjects in each group reporting ≥50% reduction in average pain relative to baseline during weeks five to eight. Functional outcomes (6-minute walk test; 6MWT and Western Ontario and McMaster Universities Osteoarthritis Index) and quality of life (Patient Global Impression of Change) also were evaluated at end of treatment (EOT).

RESULTS

A greater proportion of subjects in the PNS groups (60%; 12/20) than in the placebo (sham) group (24%; 5/21) responded with ≥50% pain relief relative to baseline (p = 0.028) during the primary endpoint (weeks 5-8). Subjects in the PNS group also walked a significantly greater distance at EOT than did those in the placebo (sham) group (6MWT; +47% vs -9% change from baseline; p = 0.048, n = 18 vs n = 20 completed the test, respectively). Prospective follow-up to 12 months is ongoing.

CONCLUSIONS

This study provides evidence that percutaneous PNS decreases persistent pain, which leads to improved functional outcomes after TKA at EOT.

Volatile Anesthetic Use Versus Total Intravenous Anesthesia for Patients Undergoing Heart Valve Surgery: A Nationwide Population-Based Study

BACKGROUND

Many studies have suggested that volatile anesthetic use may improve postoperative outcomes after cardiac surgery compared to total intravenous anesthesia (TIVA) owing to its potential cardioprotective effect. However, the results were inconclusive, and few studies have included patients undergoing heart valve surgery.

METHODS

This nationwide population-based study included all adult patients who underwent heart valve surgery between 2010 and 2019 in Korea based on data from a health insurance claim database. Patients were divided based on the use of volatile anesthetics: the volatile anesthetics or TIVA groups. After stabilized inverse probability of treatment weighting (IPTW), the association between the use of volatile anesthetics and the risk of cumulative 1-year all-cause mortality (the primary outcome) and cumulative long-term (beyond 1 year) mortality were assessed using Cox regression analysis.

RESULTS

Of the 30,755 patients included in this study, the overall incidence of 1-year mortality was 8.5%. After stabilized IPTW, the risk of cumulative 1-year mortality did not differ in the volatile anesthetics group compared to the TIVA group (hazard ratio, 0.98; 95% confidence interval, 0.90-1.07; P = .602), nor did the risk of cumulative long-term mortality (hazard ratio, 0.98; 95% confidence interval, 0.93-1.04; P = .579) at a median (interquartile range) follow-up duration of 4.8 (2.6-7.6) years.

CONCLUSIONS

Compared with TIVA, volatile anesthetic use was not associated with reduced postoperative mortality risk in patients undergoing heart valve surgery. Our findings indicate that the use of volatile anesthetics does not have a significant impact on mortality after heart valve surgery. Therefore, the choice of anesthesia type can be based on the anesthesiologists' or institutional preference and experience.

Association between modified frailty index and postoperative delirium in patients after cardiac surgery: A cohort study of 2080 older adults

AIM

To evaluate the association between frailty and postoperative delirium (POD) in elderly cardiac surgery patients.

METHODS

A retrospective study was conducted of older patients admitted to the intensive care unit after cardiac surgery at a tertiary academic medical center in Boston from 2008 to 2019. Frailty was measured using the Modified Frailty Index (MFI), which categorized patients into frail (MFI ≥3) and non-frail (MFI = 0-2) groups. Delirium was identified using the confusion assessment method for the intensive care unit and nursing notes. Logistic regression models were used to examine the association between frailty and POD, and odds ratios (OR) with 95% confidence intervals (CI) were calculated.

RESULTS

Of the 2080 patients included (median age approximately 74 years, 30.9% female), 614 were frail and 1466 were non-frail. The incidence of delirium was significantly higher in the frail group (29.2% vs. 16.4%, p < 0.05). After adjustment for age, sex, race, marital status, Acute Physiology Score III (APSIII), sequential organ failure assessment (SOFA), albumin, creatinine, hemoglobin, white blood cell count, type of surgery, alcohol use, smoking, cerebrovascular disease, use of benzodiazepines, and mechanical ventilation, multivariate logistic regression indicated a significantly increased risk of delirium in frail patients (adjusted OR: 1.61, 95% CI: 1.23-2.10, p < 0.001, E-value: 1.85).

CONCLUSIONS

Frailty is an independent risk factor for POD in older patients after cardiac surgery. Further research should focus on frailty assessment and tailored interventions to improve outcomes.

ICU admission Braden score independently predicts delirium in critically ill patients with ischemic stroke

BACKGROUND

Delirium is a common and severe complication in intensive care unit (ICU) patients with acute ischemic stroke, exacerbating cognitive and physical impairments. It prolongs hospitalization, increases healthcare costs, and raises mortality risk. Early prediction is crucial because it facilitates prompt interventions that could possibly reverse or alleviate the detrimental consequences of delirium. Braden scores, traditionally used to assess pressure injury risk, could also signal frailty, providing an early warning of delirium and aiding in prompt and effective patient management.

OBJECTIVE

To examine the association between the Braden score and delirium.

METHODS

A retrospective analysis of adult ischemic stroke patients in the ICU of a tertiary academic medical center in Boston from 2008 to 2019 was performed. Braden scores were obtained on admission for each patient. Delirium, the primary study outcome, was assessed using the Confusion Assessment Method for Intensive Care Unit and a review of nursing notes. The association between Braden score and delirium was determined using Cox proportional hazards modeling, with hazard ratios (HR) and 95% confidence intervals (CI) calculated.

RESULTS

The study included 3,680 patients with a median age of 72 years, of whom 1,798 were women (48.9 %). The median Braden score at ICU admission was 15 (interquartile range 13-17). After adjustment for demographics, laboratory tests, severity of illness, and comorbidities, the Braden score was inversely associated with the risk of delirium (adjusted HR: 0.94, 95 % CI: 0.92-0.96, P < 0.001).

CONCLUSIONS

The Braden score may serve as a convenient and simple screening tool to identify the risk of delirium in ICU patients with ischemic stroke.

IMPLICATION FOR CLINICAL PRACTICE

The use of the Braden score as a predictor of delirium in ischemic stroke patients in the ICU allows early identification of high-risk patients. This facilitates timely intervention, thereby improving patient outcomes and potentially reducing healthcare costs.

The hospital frailty risk score effectively predicts adverse outcomes in patients with atrial fibrillation in the intensive care unit

Background

Atrial fibrillation (AF) and frailty are significant global public health problems associated with advancing age. However, the relationship between frailty and older patients with AF in the intensive care unit (ICU) has not been thoroughly investigated. This study aimed to investigate whether the hospital frailty risk score (HFRS) is associated with adverse outcomes in older patients with AF in the ICU.

Methods

This was the first retrospective analysis of older patients with AF admitted to the ICU between 2008 and 2019 at a tertiary academic medical center in Boston. The HFRS was used to measure frailty severity. The outcomes of interest were in-hospital and 30-day mortality and the incidence of sepsis and ischemic stroke.

Results

There were 7,792 participants aged approximately 80 years, almost half (44.9%) of whom were female. Among this group, 2,876 individuals were identified as non-frail, while 4,916 were classified as frail. The analysis revealed a significantly greater incidence of in-hospital (18.8% compared to 7.6%) and 30-day mortality (24.5% versus 12.3%) in the frail group. After accounting for potential confounding factors, a multivariate Cox proportional hazards regression analysis revealed that frail participants had a 1.56-fold greater risk of mortality within 30 days (95% CI = 1.38-1.76, p < 0.001).

Conclusions

Frailty is an independent risk factor for adverse outcomes in older patients with AF admitted to the ICU. Therefore, prioritizing frailty assessment and implementing specific intervention strategies to improve prognostic outcomes are recommended.

Video Laryngoscopy vs Direct Laryngoscopy for Endotracheal Intubation in the Operating Room: A Cluster Randomized Clinical Trial

Importance

Endotracheal tubes are typically inserted in the operating room using direct laryngoscopy. Video laryngoscopy has been reported to improve airway visualization; however, whether improved visualization reduces intubation attempts in surgical patients is unclear.

Objective

To determine whether the number of intubation attempts per surgical procedure is lower when initial laryngoscopy is performed using video laryngoscopy or direct laryngoscopy.

Design, Setting, and Participants

Cluster randomized multiple crossover clinical trial conducted at a single US academic hospital. Patients were adults aged 18 years or older having elective or emergent cardiac, thoracic, or vascular surgical procedures who required single-lumen endotracheal intubation for general anesthesia. Patients were enrolled from March 30, 2021, to December 31, 2022. Data analysis was based on intention to treat.

Interventions

Two sets of 11 operating rooms were randomized on a 1-week basis to perform hyperangulated video laryngoscopy or direct laryngoscopy for the initial intubation attempt.

Main Outcomes and Measures

The primary outcome was the number of operating room intubation attempts per surgical procedure. Secondary outcomes were intubation failure, defined as the responsible clinician switching to an alternative laryngoscopy device for any reason at any time, or by more than 3 intubation attempts, and a composite of airway and dental injuries.

Results

Among 8429 surgical procedures in 7736 patients, the median patient age was 66 (IQR, 56-73) years, 35% (2950) were women, and 85% (7135) had elective surgical procedures. More than 1 intubation attempt was required in 77 of 4413 surgical procedures (1.7%) randomized to receive video laryngoscopy vs 306 of 4016 surgical procedures (7.6%) randomized to receive direct laryngoscopy, with an estimated proportional odds ratio for the number of intubation attempts of 0.20 (95% CI, 0.14-0.28; P < .001). Intubation failure occurred in 12 of 4413 surgical procedures (0.27%) using video laryngoscopy vs 161 of 4016 surgical procedures (4.0%) using direct laryngoscopy (relative risk, 0.06; 95% CI, 0.03-0.14; P < .001) with an unadjusted absolute risk difference of -3.7% (95% CI, -4.4% to -3.2%). Airway and dental injuries did not differ significantly between video laryngoscopy (41 injuries [0.93%]) vs direct laryngoscopy (42 injuries [1.1%]).

Conclusion and Relevance

In this study among adults having surgical procedures who required single-lumen endotracheal intubation for general anesthesia, hyperangulated video laryngoscopy decreased the number of attempts needed to achieve endotracheal intubation compared with direct laryngoscopy at a single academic medical center in the US. Results suggest that video laryngoscopy may be a preferable approach for intubating patients undergoing surgical procedures.

Trial Registration

ClinicalTrials.gov Identifier: NCT04701762.

Intraoperative Normal Saline Administration and Acute Kidney Injury in Patients Undergoing Liver Transplantation

BACKGROUND

Normal saline is still used in patients undergoing living donor liver transplantation (LDLT) with normonatremia. We investigated whether the normal saline administered during LDLT is associated with the increased risk of acute kidney injury (AKI) compared with the balanced crystalloids.

METHODS

We reviewed 1011 cases undergoing LDLT. The primary exposure variable was normal saline administered intraoperatively compared with the balanced crystalloid. To compare the risk of AKI after adjusting for potential confounders of baseline characteristics and surgical parameters, a propensity score matching analysis was performed. As a sensitivity analysis, ordinal logistic regression analysis was performed for AKI using inverse probability of treatment weighting (IPTW).

RESULTS

The incidence of AKI was significantly higher in the saline group (n = 88/174, 50.6%) than in the balanced group (n = 67/174, 38.5%) after matching (P = .010). The incidence of stage 2 or 3 AKI was also significantly higher in the saline group (n = 26/174, 14.9%) than in the balanced group (n = 43/174, 24.7%) after matching (P = .022). The length of hospital stay was significantly longer in the saline group than in the balanced group after matching. Ordinal logistic regression analysis using IPTW showed that the saline group showed a significant association of saline administration with the risk of AKI (odds ratio 1.23, 95% CI 1.05-1.28, P = .013).

CONCLUSION

Our propensity score analysis using propensity score matching and IPTW showed that normal saline administration during LDLT is associated with a high risk of postoperative AKI and longer hospital stays. However, our results should be interpreted carefully due to the relatively long period of data collection.

Etomidate versus Ketamine as Prehospital Induction Agent in Patients with Suspected Severe Traumatic Brain Injury

BACKGROUND

Severe traumatic brain injury is a leading cause of morbidity and mortality among young people around the world. Prehospital care focuses on the prevention and treatment of secondary brain injury and commonly includes tracheal intubation after induction of general anesthesia. The choice of induction agent in this setting is controversial. This study therefore investigated the association between the chosen induction medication etomidate versus S(+)-ketamine and the 30-day mortality in patients with severe traumatic brain injury who received prehospital airway management in the Netherlands.

METHODS

This study is a retrospective analysis of the prospectively collected observational data of the Brain Injury: Prehospital Registry of Outcomes, Treatments and Epidemiology of Cerebral Trauma (BRAIN-PROTECT) cohort study. Patients with suspected severe traumatic brain injury who were transported to a participating trauma center and who received etomidate or S(+)-ketamine for prehospital induction of anesthesia for advanced airway management were included. Statistical analyses were performed with multivariable logistic regression and inverse probability of treatment weighting analysis.

RESULTS

In total, 1,457 patients were eligible for analysis. No significant association between the administered induction medication and 30-day mortality was observed in unadjusted analyses (32.9% mortality for etomidate versus 33.8% mortality for S(+)-ketamine; P = 0.716; odds ratio, 1.04; 95% CI, 0.83 to 1.32; P = 0.711), as well as after adjustment for potential confounders (odds ratio, 1.08; 95% CI, 0.67 to 1.73; P = 0.765; and risk difference 0.017; 95% CI, -0.051 to 0.084; P = 0.686). Likewise, in planned subgroup analyses for patients with confirmed traumatic brain injury and patients with isolated traumatic brain injury, no significant differences were found. Consistent results were found after multiple imputations of missing data.

CONCLUSIONS

The analysis found no evidence for an association between the use of etomidate or S(+)-ketamine as an anesthetic agent for intubation in patients with traumatic brain injury and mortality after 30 days in the prehospital setting, suggesting that the choice of induction agent may not influence the patient mortality rate in this population.

EDITOR’S PERSPECTIVE

Preoperative Anemia and Postoperative Outcomes in Cardiac Surgery: A Mediation Analysis Evaluating Intraoperative Transfusion Exposures

BACKGROUND

Preoperative anemia is associated with adverse outcomes in cardiac surgery, yet it remains unclear what proportion of this association is mediated through red blood cell (RBC) transfusions.

METHODS

This is a historical observational cohort study of adults undergoing coronary artery bypass grafting or valve surgery on cardiopulmonary bypass at an academic medical center between May 1, 2008, and May 1, 2018. A mediation analysis framework was used to evaluate the associations between preoperative anemia and postoperative outcomes, including a primary outcome of acute kidney injury (AKI). Intraoperative RBC transfusions were evaluated as mediators of preoperative anemia and outcome relationships. The estimated total effect, average direct effect of preoperative anemia, and percent of the total effect mediated through transfusions are presented with 95% confidence intervals and P -values.

RESULTS

A total of 4117 patients were included, including 1234 (30%) with preoperative anemia. Overall, 437 of 4117 (11%) patients went on to develop AKI, with a greater proportion of patients having preoperative anemia (219 of 1234 [18%] vs 218 of 2883 [8%]). In multivariable analyses, the presence of preoperative anemia was associated with increased postoperative AKI (6.4% [4.2%-8.7%] absolute difference in percent with AKI, P < .001), with incremental decreases in preoperative hemoglobin concentrations displaying greater AKI risk (eg, 11.9% [6.9%-17.5%] absolute increase in probability of AKI for preoperative hemoglobin of 9 g/dL compared to a reference of 14 g/dL, P < .001). The association between preoperative anemia and postoperative AKI was primarily due to direct effects of preoperative anemia (5.9% [3.6%-8.3%] absolute difference, P < .001) rather than mediated through intraoperative RBC transfusions (7.5% [-4.3% to 21.1%] of the total effect mediated by transfusions, P = .220). Preoperative anemia was also associated with longer hospital durations (1.07 [1.05-1.10] ratio of geometric mean length of stay, P < .001). Of this total effect, 38% (22%, 62%; P < .001) was estimated to be mediated through subsequent intraoperative RBC transfusion. Preoperative anemia was not associated with reoperation or vascular complications.

CONCLUSIONS

Preoperative anemia was associated with higher odds of AKI and longer hospitalizations in cardiac surgery. The attributable effects of anemia and transfusion on postoperative complications are likely to differ across outcomes. Future studies are necessary to further evaluate mechanisms of anemia-associated postoperative organ injury and treatment strategies.

Association of long-term use of non-steroidal anti-inflammatory drugs with knee osteoarthritis: a prospective multi-cohort study over 4-to-5 years

This study examines the long-term impact of non-steroidal anti-inflammatory drugs (NSAIDs) on the progression of symptoms and structural deterioration of the joint in knee osteoarthritis. The study analyzes data from 4197 participants (8394 knees) across the Osteoarthritis Initiative (OAI), Multicenter Osteoarthritis Study (MOST), and Cohort Hip and Cohort Knee (CHECK) over 4-to-5 years. Adjustments were made for major covariates. We focussed on binary outcomes to assess the presence or absence of significant changes. We found that, relative to non-users, individuals using NSAIDs long-term were significantly more likely to experience aggravated symptoms exceeding the minimally clinically important difference, specifically, pain (OR: 2.04, 95% CI: 1.66-2.49), disability (OR: 2.21, 95% CI: 1.74-2.80), and stiffness (OR: 1.58, 95% CI: 1.29-1.93). Long-term users also faced a higher probability than non-users of having total knee replacement (OR: 3.13, 95% CI: 2.08-4.70), although no significant difference between long-term users and non-users was observed for structural deterioration in the knee joint (OR: 1.25, 95% CI: 0.94-1.65). While acknowledging the limitations of this study due to its observational design and the potential for bidirectional causality, these findings suggest that long-term NSAID use could accelerate the progression to total knee replacement by markedly exacerbating symptoms.

Should the Vasoactive Inotropic Score be a Determinant for Early Initiation of VA ECMO in Postcardiotomy Cardiogenic Shock?

OBJECTIVES

The authors investigated the role of early venoarterial extracorporeal membrane oxygenation (VA ECMO) implantation in patients with postcardiotomy cardiogenic shock (PCS) on mortality and morbidity when integrating vasoactive-inotropic score (VIS) and type of catecholamine support.

DESIGN

A retrospective, multicenter, observational study with propensity-weight matching.

SETTING

Four university-affiliated intensive care units.

PARTICIPANTS

Patients with PCS in the operating room.

INTERVENTIONS

Early VA ECMO support.

MEASUREMENTS AND MAIN RESULTS

Of 2,742 patients screened during the study period, 424 (16%) patients were treated with inotropic drugs, and 75 (3%) patients were supported by VA ECMO in the operating room. Patients supported by VA ECMO had a higher use of vasopressor and inotropic drugs, with a higher VIS score. After propensity matching (integrating VIS and catecholamines type), mortality (56% v 20%, p < 0.001) and morbidity (cardiac, renal, transfusion) were higher in patients supported by VA ECMO than in a matched control group.

CONCLUSIONS

When matching integrated the pre-ECMO VIS and the type of catecholamines, VA ECMO remained associated with high mortality and morbidity, suggesting that VIS alone should not be used as a main determinant of VA ECMO implantation.

Association between preoperative anemia optimization and major complications after non-cardiac surgery: a retrospective analysis

BACKGROUND

Anemia is common in the preoperative setting and associated with increased postoperative complications and mortality. However, it is unclear if preoperative anemia optimization reduces postoperative complications. We aimed to assess the association between preoperative anemia optimization and a composite endpoint of major cardiovascular, renal, and pulmonary complications and all-cause mortality within 30 days after noncardiac surgery in adult patients.

METHODS

In this retrospective analysis preoperative anemia was defined as hemoglobin concentration below 12.0 g.dl-1 in women and 13.0 g.dl-1 in men within 6 months before surgery. A propensity score-based generalized estimating equation analysis was used to determine the association between preoperative anemia optimization and the primary outcome. Moreover, mediation analysis was conducted to investigate whether intraoperative red blood cell transfusion or duration of intraoperative hypotension were mediators of the relation between anemia optimization and the primary outcome.

RESULTS

Fifty-seven hundred anemia optimized, and 8721 non-optimized patients met study criteria. The proportion of patients having any component of the composite of major complications and all-cause mortality was 21.5% in the anemia-optimized versus 18.0% in the non-optimized, with confounder-adjusted odds ratio estimate of 0.99 (95% CI 0.86‒1.15) for anemia optimization versus non-optimization, p = 0.90. Intraoperative red blood cell transfusion had a minor mediation effect on the relationship between preoperative anemia optimization and the primary outcome, whereas duration of intraoperative hypotension was not found to be a mediator.

CONCLUSION

Preoperative anemia optimization did not appear to be associated with a composite outcome of major in-hospital postoperative cardiovascular, renal, and pulmonary complications and all-cause in-hospital mortality.

Caffeine administration to treat oversedation after general anesthesia: A retrospective analysis

STUDY OBJECTIVE

Our institution has adopted an informal practice of administering postoperative caffeine to expedite anesthesia recovery for patients with excessive sedation. This study aimed to determine whether caffeine administration was associated with improved sedation recovery and reduced risk of respiratory complications.

DESIGN

Single-center, retrospective, observational study.

SETTING

Quaternary medical center.

PATIENTS

We included adult patients who were admitted to a postanesthesia recovery care unit (PACU) after general anesthesia and had evidence of postoperative sedation (Richmond Agitation Sedation Score [RASS] < 0). Patients were seen from May 5, 2018, through December 31, 2020.

INTERVENTIONS

Patients were categorized according to caffeine administration (0 vs 250 mg).

MEASUREMENTS

Sedation was measured with RASS. To account for potential confounding, binary and ordinal logistic regression with inverse probability of treatment weighting (IPTW) were used to compare RASS and episodes of severe respiratory complications within 48 h after PACU discharge.

MAIN RESULTS

We identified 47,222 adult surgical patients with evidence of sedation in the PACU, and of these, 1892 (4.0%) were intravenously administered caffeine. Patients who received caffeine had more sedation in the PACU. In the IPTW-adjusted analysis, caffeine administration was associated with improved sedation scores after PACU discharge (ordinal logistic regression odds ratio [OR], 1.13 [95% CI, 1.00-1.28]; P = .04 for the first RASS score after PACU discharge) but increased risk of respiratory complications (OR, 2.99 [95% CI, 1.44-6.24]; P = .003) and emergency response team activation (OR, 7.18 [95% CI, 2.85-18.10]; P < .001).

CONCLUSIONS

In this observational study, caffeine administration during anesthesia recovery was associated with improved sedation scores. However, it was also associated with an increased risk of respiratory complications, possibly reflecting selection bias (ie, administering caffeine to higher-risk patients). Patients with signs of excessive sedation during anesthesia recovery may benefit from enhanced postoperative respiratory monitoring.

Does ICU admission dysphagia independently contribute to delirium risk in ischemic stroke patients? Results from a cohort study

BACKGROUND

Delirium is prevalent in ischemic stroke patients, particularly those in the intensive care unit (ICU), and it poses a significant burden on patients and caregivers, leading to increased mortality rates, prolonged hospital stays, and impaired cognitive function. Dysphagia, a common symptom in critically ill patients with ischemic stroke, further complicates their condition. However, the association between dysphagia and delirium in this context remains unclear. The objective of this study was to investigate the correlation between dysphagia and delirium in ICU patients with ischemic stroke.

METHODS

A retrospective analysis was conducted on adult patients diagnosed with ischemic stroke at a medical center in Boston. Ischemic stroke cases were identified using the ninth and tenth revisions of the International Classification of Diseases. Dysphagia was defined as a positive bedside swallowing screen performed by medical staff on the day of ICU admission, while delirium was assessed using the ICU Confusion Assessment Method and review of nursing notes. Logistic regression models were used to explore the association between dysphagia and delirium. Causal mediation analysis was employed to identify potential mediating variables.

RESULTS

The study comprised 1838 participants, with a median age of approximately 70 years, and 50.5% were female. Among the total study population, the prevalence of delirium was 43.4%, with a higher prevalence observed in the dysphagia group (60.7% vs. 40.8%, p < 0.001) compared to the non-dysphagia group. After adjusting for confounding factors including age, sex, race, dementia, depression, sedative medications, history of falls, visual or hearing deficit, sequential organ failure score, and Glasgow coma score, multifactorial logistic regression analysis demonstrated a significant association between dysphagia and an increased likelihood of delirium (odds ratio [OR]: 1.48; 95% confidence interval [CI]: 1.07-2.05; p = 0.018; E-value = 1.73). Causal mediation analysis revealed that serum albumin levels partially mediated the association between dysphagia and delirium in critically ill patients with ischemic stroke (average causal mediated effect [ACME]: 0.02, 95% CI: 0.01 to 0.03; p < 0.001).

CONCLUSION

ICU admission dysphagia may independently contribute to the risk of delirium in patients with ischemic stroke. Early identification and intervention in ischemic stroke patients with dysphagia may help mitigate the risk of delirium and improve patient prognosis.

Association Between Cannabis Use and Opioid Consumption, Pain, and Respiratory Complications After Surgery: A Retrospective Cohort Analysis

BACKGROUND

Cannabis is a widely used illicit drug with effects on different pain pathways. However, interactions between cannabis and postoperative pain are unclear. Cannabis smoking also affects the lungs, but the impact of cannabis use on postoperative pulmonary complications is unknown. We hypothesized that preoperative cannabis use in adults having elective surgery is associated with higher postoperative opioid consumption. Secondarily, we tested the hypothesis that cannabis use is associated with higher pain scores, hypoxemia (oxygen saturation [Spo2]/fraction of inspired oxygen [Fio2] ratio), and higher postoperative pulmonary complications compared to nonuse of cannabis.

METHODS

In this retrospective study, we included adult patients who had elective surgeries at Cleveland Clinic Main Campus between January 2010 and December 2020. The exposure was use of cannabis within 30 days before surgery, and the control group never used cannabis. Patients who had regional anesthesia or chronic pain diagnosis were excluded. The primary outcome was postoperative opioid consumption; 3 secondary outcomes were time-weighted average (TWA) postoperative pain score, TWA Spo2/Fio2 ratio, and composite of pulmonary complications after surgery. We assessed the association between cannabis use and opioid consumption during the first 24 postoperative hours using linear regression on log-transformed opioid consumption with a propensity score-based method (inverse probability of treatment weighting [IPTW]) adjusting for confounders. We further adjusted for imbalanced confounding variables after IPTW was applied.

RESULTS

In total, 1683 of 34,521 patients were identified as cannabis users. Cannabis use was associated with increased opioid consumption, with an adjusted ratio of geometric means (95% confidence interval [CI]) of 1.30 (1.22-1.38; P < .0001) for cannabis users versus nonusers. Secondarily, (1) cannabis use was associated with increased TWA pain score, with a difference in means of 0.57 (95% CI, 0.46-0.67; P < .0001); (2) cannabis use was not associated with TWA Spo2/Fio2, with an adjusted difference in means of 0.5 (95% CI, -3.1 to 4.2; P = .76); and (3) cannabis use was not associated with a collapsed composite of pulmonary complications, with estimated odds ratio of 0.90 (95% CI, 0.71-1.13; P = .34).

CONCLUSIONS

Adult cannabis users undergoing surgeries were found to have significantly higher postoperative opioid consumption and pain scores than nonusers. Cannabis use did not have a clinically meaningful association with hypoxia or composite pulmonary complications.

Comparing COVID-19 and influenza: Epidemiology, clinical characteristics, outcomes and mortality in the ICU

RATIONALE

Several authors have compared COVID-19 infection with influenza in the ICU.

OBJECTIVE

This study aimed to compare the baseline clinical profiles, care procedures, and mortality outcomes of patients admitted to the intensive care unit, categorized by infection status (Influenza vs. COVID-19).

METHODS

Retrospective observational study. Data were extracted from the Toulouse University Hospital from March 2014 to March 2021. To compare survival curves, we plotted the survival at Day-90 using the Kaplan-Meier curve and conducted a log-rank test. Additionally, we performed propensity score matching to adjust for confounding factors between the COVID-19 and influenza groups. Furthermore, we use the CART model for multivariate analysis.

RESULTS

The study included 363 patients admitted to the ICU due to severe viral pneumonia: 152 patients (41.9 %) with influenza and 211 patients (58.1 %) with COVID-19. COVID-19 patients exhibited a higher prevalence of cardiovascular risk factors, whereas influenza patients had significantly higher severity scores (SOFA: 10 [6-12] vs. 6 [3-9], p<0.01 and SAPS II: 51 [35-67] vs. 37 [29-50], p<0.001). Overall mortality rates were comparable between the two groups (27.6 % (n = 42) in the influenza group vs. 21.8 % (n = 46) in the COVID-19 group, p=NS). Mechanical ventilation was more commonly employed in the influenza group (76.3 % (n = 116) vs. 59.7 % (n = 126), p<0.001); however, COVID-19 patients required longer durations of mechanical ventilation (18 [9-29] days vs. 13 [5-24] days, p<0.006) and longer hospital stays (23 [13-34] days vs. 18.5 [9-34.5] days, p = 0.009). The CART analysis revealed that the use of extra renal replacement therapy was the most influential prognostic factor in the influenza group, while the PaO2/FiO2-PEEP ratio played a significant role in the COVID-19 group.

CONCLUSIONS

Despite differences in clinical presentation and prognostic factors, the mortality rates at 90 days, after adjusting for confounding factors, were similar between COVID-19 and influenza patients.

Association between Endometriosis and Surgical Complications among Benign Hysterectomies

STUDY OBJECTIVE

To investigate the effect of endometriosis on perioperative outcomes in patients undergoing hysterectomy for benign disease.

DESIGN

A retrospective cohort study.

SETTING

The American College of Surgeons National Surgical Quality Improvement Program database.

PATIENTS

A total of 127 556 hysterectomies performed for benign gynecologic indications INTERVENTIONS: Differences in the primary outcomes were compared between patients with and without endometriosis after adjustment for group differences in covariates using inverse probability of treatment weighting approach.

MEASURES AND MAIN RESULTS

Of the 127 556 hysterectomies identified, 19 618 (15.4%) had a diagnosis of endometriosis. Patients with endometriosis were younger with a lower prevalence of chronic comorbidities but had higher rates of concurrent pelvic inflammatory disease and previous abdominal operations. The incidence of postoperative complications was higher in patients with endometriosis (9.9% vs 8.1%; odds ratio [OR], 1.25; 95% confidence interval [CI], 1.17-1.34). The incidence of 30-day mortality (0.1% vs 0.03%; OR, 1.98; 95% CI, 0.69-5.65) and reoperations (1.50% vs 1.36%; OR, 1.18; 95% CI, 0.98-1.42) were not different in patients with and without endometriosis.

CONCLUSION

Postoperative complications are more likely in hysterectomies involving endometriosis than those without endometriosis, likely owing to anatomic distortion incurring increased surgical complexity. Patients and surgeons should be aware of the increased risk of complications and plan for mitigating these increased risks before and during surgery for suspected endometriosis.

Association Between Intraoperative Landiolol Use and In-Hospital Mortality After Coronary Artery Bypass Grafting: A Nationwide Observational Study in Japan

BACKGROUND

Ischemic heart disease is a leading cause of death worldwide, and coronary artery bypass grafting (CABG) is a major treatment. Landiolol is an ultra-short-acting beta-antagonist known to prevent postoperative atrial fibrillation. However, the effectiveness of intraoperative landiolol on mortality remains unknown. This study aimed to evaluate the association between intraoperative landiolol use and the in-hospital mortality in patients undergoing CABG.

METHODS

To conduct this retrospective cohort study, we used data from the Japanese Diagnosis Procedure Combination inpatient database. All patients who underwent CABG during hospitalization between July 1, 2010, and March 31, 2020, were included. Patients who received intraoperative landiolol were defined as the landiolol group, whereas the other patients were defined as the control group. The primary outcome was in-hospital mortality. Propensity score matching was used to compare the landiolol and control groups.

RESULTS

In total, 118,506 patients were eligible for this study, including 25,219 (21%) in the landiolol group and 93,287 (79%) in the control group. One-to-one propensity score matching created 24,893 pairs. After propensity score matching, the in-hospital mortality was significantly lower in the landiolol group than that in the control group (3.7% vs 4.3%; odds ratio 0.85; 95% confidence interval 0.78 to 0.94; P = .010).

CONCLUSIONS

Intraoperative landiolol use was associated with decreased in-hospital mortality in patients undergoing CABG. Further randomized controlled trials are required to confirm these findings.

Pulmonary artery catheter monitoring versus arterial waveform-based monitoring during liver transplantation: a retrospective cohort study

Although pulmonary artery catheter (PAC) has been used during liver transplantation surgery, the usefulness of PAC has rarely been investigated. We evaluated whether the use of PAC is associated with better clinical outcomes compared to arterial waveform-based monitoring after liver transplantation. A total of 1565 cases undergoing liver transplantation were reviewed. We determined whether patients received PAC or not and divided our cohort into the PAC with hemodynamic monitoring using PAC and the non-PAC with arterial waveform-based monitoring using FloTrac-Vigileo. Propensity score matching was performed. Acute kidney injury (AKI), early allograft dysfunction (EAD) and 1-year all-cause mortality or graft failure were compared in the matched cohorts. Logistic regression analysis was performed in the inverse probability of treatment-weighted (IPTW) cohort for postoperative EAD and AKI, respectively. Five-year overall survival was compared between the two groups. In the matched cohort, there was no significant difference in the incidence of AKI, EAD, length of hospital or ICU stay, and 1-year all-cause mortality between the groups. In the IPTW cohort, the use of PAC was not a significant predictor for AKI or EAD (AKI: odds ratio (95% confidence interval) of 1.20 (0.47-1.56), p = 0.229; EAD: 0.99 (0.38-1.14), p = 0.323). There was no significant difference in the survival between groups after propensity score matching (Log-rank test p = 0.578). In conclusion, posttransplant clinical outcomes were not significantly different between the groups with and without PAC. Anesthetic management without the use of PAC may be possible in low-risk patients during liver transplantation. The risk should be carefully assessed by considering MELD scores, ischemic time, surgical history, previous treatment of underlying liver disease, and degree of portal and pulmonary hypertension.Registration: https://clinicaltrials.gov/ct2/show/NCT05457114 (registration date: July 15, 2022).

Postanesthesia Care Unit Recovery Time According to Volatile Anesthetic Used in Clinical Practice

BACKGROUND

Whether volatile anesthetic solubility affects postanesthesia recovery time in clinical practice is unclear. We investigated the association among 3 volatile agents and 2 clinically relevant outcomes-postanesthesia care unit (PACU) recovery time (time from PACU admission to fulfillment of discharge criteria) and oversedation (Richmond Agitation-Sedation Scale score ≤-3)-as a potential contributor to delaying PACU discharge. The volatile agents studied were isoflurane, desflurane, and sevoflurane. We hypothesized that increased solubility of the volatile agent (isoflurane versus desflurane or sevoflurane) would be associated with longer PACU recovery time and higher rates of oversedation.

METHODS

This retrospective observational study included adults (≥18 years) who underwent surgical procedures under general anesthesia with a volatile agent and were admitted to the PACU from May 5, 2018, to December 31, 2020. The primary outcome was PACU recovery time, and the secondary outcome was oversedation. PACU recovery time was log-transformed and analyzed with linear regression. Oversedation was analyzed by using logistic regression. To account for potential confounding, inverse probability of treatment weighting (IPTW) was used. Pairwise comparisons of the 3 agents were performed, with P < .017 (Bonferroni-adjusted) considered significant.

RESULTS

Of 47,847 patients included, 11,817 (24.7%) received isoflurane, 11,286 (23.6%) received desflurane, and 24,744 (51.7%) received sevoflurane. Sevoflurane had an estimated 4% shorter PACU recovery time (IPTW-adjusted median [interquartile range {IQR}], 61 [42-89] minutes) than isoflurane (64 [44-92] minutes) (ratio of geometric means [98.3% confidence interval {CI}], 0.96 [0.95-0.98]; P < .001). Differences in PACU recovery time between desflurane and the other agents were not significant. The IPTW-adjusted frequency of oversedation was 8.8% for desflurane, 12.2% for sevoflurane, and 16.7% for isoflurane; all pairwise comparisons were observed to be significant (odds ratio [98.3% CI], 0.70 [0.62-0.79] for desflurane versus sevoflurane, 0.48 [0.42-0.55] for desflurane vs isoflurane, and 0.69 [0.63-0.76] for sevoflurane versus isoflurane; all P < .001). Although oversedated patients had longer PACU recovery time, differences in the oversedation rate across agents did not result in meaningful differences in time to PACU recovery.

CONCLUSIONS

In clinical practice, only small, clinically unimportant differences in PACU recovery time were observed between the volatile anesthetics. Although oversedation was associated with increased PACU recovery time, differences in the rate of oversedation among agents were insufficient to produce meaningful differences in overall PACU recovery time across the 3 volatile agents. Practical attempts to decrease PACU recovery time should address factors other than volatile agent selection.

Postoperative NSAIDs use and the risk of anastomotic leakage after restorative resection for colorectal cancer

BACKGROUND

Although non-steroidal anti-inflammatory drugs (NSAIDs) are useful options for multimodal opioid-sparing analgesia, their effect on anastomotic leakage (AL) after colorectal surgery remains unclear. We aimed to investigate the association between early postoperative NSAID use and AL occurrence in patients who underwent colorectal cancer surgery at a high-volume tertiary care center.

METHODS

This retrospective observational study included all adult patients who underwent elective colorectal cancer resection surgery during 2011-2021 at a tertiary teaching hospital. Based on NSAID use within five postoperative days, patients were classified into either NSAID or no NSAID groups. We performed multivariable logistic regression analysis for the primary outcome, AL, within the first 30 postoperative days, before and after propensity score analysis using stabilized inverse probability of treatment weighting (sIPTW).

RESULTS

Among the 7928 patients analyzed, 0.6% experienced AL after surgery. The occurrence rates of AL were 1.7% (12/714) and 0.5% (37/7214) in the NSAID and no NSAID groups, respectively. Multivariable logistic regression analysis revealed that early postoperative NSAID use was significantly associated with AL [odds ratio (OR), 3.41; 95% confidence interval (CI), 1.76-6.60; P < 0.001]. Significance was maintained after sIPTW (OR, 3.65; 95% CI, 1.86-6.72; P < 0.001).

CONCLUSION

Early postoperative NSAID use was significantly associated with AL in patients undergoing colorectal cancer surgery at a high-volume tertiary care center. Further prospective studies are required to investigate NSAIDs' clinically meaningful unfavorable effects following colorectal cancer surgery.

The Role of Recipient Thyroid Hormone Supplementation in Primary Graft Dysfunction After Heart Transplantation: A Propensity-Adjusted Analysis

OBJECTIVES

To investigate whether recipient administration of thyroid hormone (liothyronine [T3]) is associated with reduced rates of primary graft dysfunction (PGD) after orthotopic heart transplantation.

DESIGN

Retrospective cohort study.

SETTING

Single-center, university hospital.

PARTICIPANTS

Adult patients undergoing orthotopic heart transplantation.

INTERVENTIONS

A total of 609 adult heart transplant recipients were divided into 2 cohorts: patients who did not receive T3 (no T3 group, from 2009 to 2014), and patients who received T3 (T3 group, from 2015 to 2019). Propensity-adjusted logistic regression was performed to assess the association between T3 supplementation and PGD.

MEASUREMENTS AND MAIN RESULTS

After applying exclusion criteria and propensity-score analysis, the final cohort included 461 patients. The incidence of PGD was not significantly different between the groups (33.9% no T3 group v 40.8% T3 group; p = 0.32). Mortality at 30 days (3% no T3 group v 2% T3 group; p = 0.53) and 1 year (10% no T3 group v 12% T3 group; p = 0.26) were also not significantly different. When assessing the severity of PGD, there were no differences in the groups' rates of moderate PGD (not requiring mechanical circulatory support other than an intra-aortic balloon pump) or severe PGD (requiring mechanical circulatory support other than an intra-aortic balloon pump). However, segmented time regression analysis revealed that patients in the T3 group were less likely to develop severe PGD.

CONCLUSIONS

These findings indicated that recipient single-dose thyroid hormone administration may not protect against the development of PGD, but may attenuate the severity of PGD.

Propensity score methods in observational research: brief review and guide for authors

Causal inference in observational research requires a careful approach to adjustment for confounding. One such approach is the use of propensity score analyses. In this editorial, we focus on the role of propensity score-based methods in estimating causal effects from non-randomised observational data. We highlight the details, assumptions, and limitations of these methods and provide authors with guidelines for the conduct and reporting of propensity score analyses.

Association between chronic pain and acute coronary syndrome in the older population: a nationwide population-based cohort study

BACKGROUND

Chronic pain (CP) may increase the risk of acute coronary syndrome (ACS); however, this issue in the older population remains unclear. Therefore, this study was conducted to clarify it.

METHODS

We used the Taiwan National Health Insurance Research Database to identify older patients with CP between 2001 and 2005 as the study cohort. Comparison cohort was the older patients without CP by matching age, sex, and index date at 1:1 ratio with the study cohort in the same period. We also included common underlying comorbidities in the analyses. The risk of ACS was compared between the two cohorts by following up until 2015.

RESULTS

A total of 17241 older patients with CP and 17241 older patients without CP were included in this study. In both cohorts, the mean age (± standard deviation) and female percentage were 73.5 (± 5.7) years and 55.4%, respectively. Spinal disorders (31.9%) and osteoarthritis (27.0%) were the most common causes of CP. Older patients with CP had an increased risk for ACS compared to those without CP after adjusting for all underlying comorbidities (adjusted sub-distribution hazard ratio [sHR] 1.18; 95% confidence interval: 1.07-1.30). The increasement of risk of ACS was more when the follow-up period was longer (adjusted sHR of < 3 years: 1.8 vs. <2 years: 1.75 vs. <1 year: 1.55).

CONCLUSIONS

CP was associated with an increased risk of ACS in the older population, and the association was more prominent when the follow-up period was longer. Early detection and intervention for CP are suggested in this population.

Comparison of lower extremity bypass and peripheral vascular intervention for chronic limb-threatening ischemia in the Medicare-linked Vascular Quality Initiative

OBJECTIVE

There is a relative lack of comparative effectiveness research on revascularization for patients with chronic limb-threatening ischemia (CLTI). We examined the association between lower extremity bypass (LEB) vs peripheral vascular intervention (PVI) for CLTI and 30-day and 5-year all-cause mortality and 30-day and 5-year amputation.

METHODS

Patients undergoing LEB and PVI of the below-the-knee popliteal and infrapopliteal arteries between 2014 and 2019 were queried from the Vascular Quality Initiative, and outcomes data were obtained from the Medicare claims-linked Vascular Implant Surveillance and Interventional Outcomes Network database. Propensity scores were calculated on 15 variables using a logistic regression model to control for imbalances between treatment groups. A 1:1 matching method was used. Kaplan-Meier survival curves and hierarchical Cox proportional hazards regression with a random intercept for site and operator nested in site to account for clustered data compared 30-day and 5-year all-cause mortality between groups. Thirty-day and 5-year amputation were subsequently compared using competing risk analysis to account for the competing risk of death.

RESULTS

There was a total of 2075 patients in each group. The overall mean age was 71 ± 11 years, 69% were male, and 76% were white, 18% were black, and 6% were of Hispanic ethnicity. Baseline clinical and demographic characteristics in the matched cohort were balanced between groups. There was no association between all-cause mortality over 30 days and LEB vs PVI (cumulative incidence, 2.3% vs 2.3% by Kaplan Meier; log-rank P-value = .906; hazard ratio [HR], 0.95; 95% confidence interval [CI], 0.62-1.44; P-value = .80). All-cause mortality over 5 years was lower for LEB vs PVI (cumulative incidence, 55.9% vs 60.1% by Kaplan Meier; log-rank P-value < .001; HR, 0.77; 95% CI, 0.70-0.86; P-value < .001). Accounting for competing risk of death, amputation over 30 days was also lower in LEB vs PVI (cumulative incidence function, 1.9% vs 3.0%; Fine and Gray P-value = .025; subHR, 0.63; 95% CI, 0.42-0.95; P-value = .025). There was no association between amputation over 5 years and LEB vs PVI (cumulative incidence function, 22.6% vs 23.4%; Fine and Gray P-value = .184; subHR, 0.91; 95% CI, 0.79-1.05; P-value = .184).

CONCLUSIONS

In the Vascular Quality Initiative-linked Medicare registry, LEB vs PVI for CLTI was associated with a lower risk of 30-day amputation and 5-year all-cause mortality. These results will serve as a foundation to validate recently published randomized controlled trial data, and to broaden the comparative effectiveness evidence base for CLTI.

Transnasal Humidified Rapid Insufflation Ventilatory Exchange Augments Oxygenation in Children With Juvenile Onset Recurrent Respiratory Papillomatosis During Surgery: A Prospective Randomized Crossover Controlled Trial

BACKGROUND

Evidence is lacking regarding the efficacy of transnasal humidified rapid insufflation ventilatory exchange (THRIVE) in tubeless anesthesia, especially in pediatric patients. This study aimed to evaluate the use of THRIVE for juvenile onset recurrent respiratory papillomatosis (JORRP) patients.

METHODS

Twenty-eight children aged 2 to 12 years with JORRP, abnormal airways, and ASA physical status II-III that presented for surgical treatment under general anesthesia were included in this study. Each patient received 2 interventions in random order, with a 5-minute washout period between treatments: apnea without oxygen supplementation and apnea with THRIVE intervention. The primary outcome apnea time was defined as the duration from withdrawal of intubation to reintubation and resumption of controlled ventilation. The secondary outcomes were the mean transcutaneous carbon dioxide (tc co2 ) increase rate, the minimum pulse oxygen saturation (Sp o2 ) during apnea, and the occurrence of unexpected adverse effects.

RESULTS

The median apnea time in the THRIVE period was significantly longer than that in the control period (8.9 [8.6-9.4] vs 3.8 [3.4-4.3] minutes; mean difference [95% confidence interval (CI)], 5.0 [4.4-5.6]; P < .001) for all patients. The rate of CO 2 change in the control period was higher than that in the THRIVE period both for patients aged 2 to 5 years old (6.29 [5.19-7.4] vs 3.22 [2.92-3.76] mm Hg min -1 ; mean difference [95% CI], 3.09 [2.27-3.67]; P < .001) and for patients aged 6 to 12 years old (4.76 [3.7-6.2] vs 3.38 [2.64-4.0] mm Hg min -1 ; mean difference [95% CI], 1.63 [0.75-2.56]; P < .001). The minimum Sp o2 was significantly higher in the THRIVE period than in the control period (mean difference [95% CI], 19.7 [14.8-22.6]; P < .001).

CONCLUSIONS

Our findings demonstrate that THRIVE safely increased the apnea time among children with JORRP undergoing surgery and decreased the rate of carbon dioxide increase. THRIVE is clinically recommended as an airway management technique for tubeless anesthesia in apneic children.

Comparative study between oxytocin and combination of tranexamic acid and ethamsylate in reducing intra-operative bleeding during emergency and elective cesarean section after 38 weeks of normal pregnancy

OBJECTIVE

Cesarean Section (CS) is associated with an increased risk of hemorrhage. Many drugs are used to decrease this risk. We aim to compare the combination of ethamsylate and tranexamic acid, oxytocin, and placebo in women undergoing CS.

METHODS

We conducted a double-blinded, randomized, placebo-controlled trial between October and December 2020 in four university hospitals in Egypt. The study included all pregnant women in labor without any complications who accepted to participate in the study between October and December 2020. The participants were divided into three groups. The subjects were randomly allocated to receive either oxytocin (30 IU in 500 ml normal saline during cesarean section), combined one gram of tranexamic acid with 250 mg of ethamsylate once before skin incision, or distilled water. Our main outcome was the amount of blood loss during the operation. The secondary outcomes were the need for blood transfusion, hemoglobin and hematocrit changes, hospital stay, operative complications, and the need for a hysterectomy. The one-way ANCOVA test was used to compare the quantitative variables between the three groups while the Chi-square test was used to compare the qualitative variables. Post hoc analysis then was performed to compare the difference between every two groups regarding the quantitative variables.

RESULTS

Our study included 300 patients who were divided equally into three groups. Tranexamic acid with ethamsylate showed the least intra-operative blood loss (605.34 ± 158.8 ml) compared to oxytocin (625.26 ± 144.06) and placebo (669.73 ± 170.69), P = 0.015. In post hoc analysis, only tranexamic acid with ethamsylate was effective in decreasing the blood loss compared to placebo (P = 0.013); however, oxytocin did not reduce blood loss compared to saline (P = 0.211) nor to tranexamic acid with ethamsylate (P = 1). Other outcomes and CS complications showed no significant difference between the three groups except for post-operative thrombosis which was significantly higher in the tranexamic and ethamsylate group, P < 0.00001 and the need for a hysterectomy which was significantly increased in the placebo group, P = 0.017.

CONCLUSION

The combination of tranexamic acid and ethamsylate was significantly associated with the least amount of blood loss. However, in pairwise comparisons, only tranexamic acid with ethamsylate was significantly better than saline but not with oxytocin. Both oxytocin and tranexamic acid with ethamsylate were equally effective in reducing intra-operative blood loss and the risk of hysterectomy; however, tranexamic acid with ethamsylate increased the risk of thrombotic events. Further research with a larger number of participants is needed.

TRIAL REGISTRATION

The study was registered on Pan African Clinical Trials Registry with the following number: PACTR202009736186159 and was approved on 04/09/2020.

Plasma-Free Strategy for Cardiac Surgery with Cardiopulmonary Bypass in Infants < 10 kg: A Retrospective, Propensity-Matched Study

BACKGROUND

Infants < 10 kg undergoing cardiac surgery with cardiopulmonary bypass (CPB) may receive either fresh frozen plasma (FFP) or other solutions in the CPB priming volume. The existing comparative studies are controversial. No study addressed the possibility of total avoidance of FFP throughout the whole perioperative course in this patient population. This retrospective, non-inferiority, propensity-matched study investigates an FFP-free strategy compared to an FFP-based strategy.

METHODS

Among patients <10 kg with available viscoelastic measurements, 18 patients who received a total FFP-free strategy were compared to 27 patients (1:1.5 propensity matching) receiving an FFP-based strategy. The primary endpoint was chest drain blood loss in the first 24 postoperative hours. The level of non-inferiority was settled at a difference of 5 mL/kg.

RESULTS

The 24-h chest drain blood loss difference between groups was -7.7 mL (95% confidence interval -20.8 to 5.3) in favor of the FFP-based group, and the non-inferiority hypothesis was rejected. The main difference in coagulation profile was a lower level of fibrinogen concentration and FIBTEM maximum clot firmness in the FFP-free group immediately after protamine, at the admission in the ICU and for 48 postoperative hours. No differences in transfusion of red blood cells or platelet concentrate were observed; patients in the FFP-free group did not receive FFP but required a larger dose of fibrinogen concentrate and prothrombin complex concentrate.

CONCLUSIONS

An FFP-free strategy in infants < 10 kg operated with CPB is technically feasible but results in an early post-CPB coagulopathy that was not completely compensated with our bleeding management protocol.

Balanced Nonopioid General Anesthesia With Lidocaine Is Associated With Lower Postoperative Complications Compared With Balanced Opioid General Anesthesia With Sufentanil for Cardiac Surgery With Cardiopulmonary Bypass: A Propensity Matched Cohort Study

BACKGROUND

There are no data on the effect of balanced nonopioid general anesthesia with lidocaine in cardiac surgery with cardiopulmonary bypass. The main study objective was to evaluate the association between nonopioid general balanced anesthesia and the postoperative complications in relation to opioid side effects.

METHODS

Patients undergoing cardiac surgery with cardiopulmonary bypass between 2019 and 2021 were identified. After exclusion of patients for heart transplantation, left ventricular assistance device, and off-pump surgery, we classified patients according to an opioid general balanced anesthesia or a nonopioid balanced anesthesia with lidocaine. The primary outcome was a collapsed composite of postoperative complications that comprise respiratory failure and confusion, whereas secondary outcomes were acute renal injury, pneumoniae, death, intensive care unit (ICU), and hospital length of stay.

RESULTS

We identified 859 patients exposed to opioid-balanced general anesthesia with lidocaine and 913 patients exposed to nonopioid-balanced general anesthesia. Propensity score matching yielded 772 individuals in each group with balanced baseline covariates. Two hundred thirty-six patients (30.5%) of the nonopioid-balanced general anesthesia versus 186 patients (24.1%) presented postoperative composite complications. The balanced lidocaine nonopioid general anesthesia group was associated with a lower proportion with the postoperative complication composite outcome OR, 0.72 (95% CI, 0.58-0.92; P = .027). The number of patients with acute renal injury, death, and hospital length of stay did not differ between the 2 groups.

CONCLUSIONS

A balanced nonopioid general anesthesia protocol with lidocaine was associated with lower odds of postoperative complication composite outcome based on respiratory failure and confusion.

Effects of sugammadex versus neostigmine on postoperative nausea and vomiting after general anesthesia in adult patients:a single-center retrospective study

We aimed to compare the effect of sugammadex to that of neostigmine with respect to the occurrence of postoperative nausea and vomiting (PONV) during the first 24 h following general anesthesia. This retrospective cohort study included patients who underwent elective surgery under general anesthesia in 2020 at an academic medical center in Seoul, South Korea. The exposure groups were determined according to whether the patient received sugammadex or neostigmine as a reversal agent. The primary outcome was PONV occurrence during the first 24 h postoperatively (overall). The association between the type of reversal agent and primary outcome was investigated using logistic regression while adjusting for confounding variables using stabilized inverse probability of treatment weighting (sIPTW). Of the 10,912 patients included in this study, 5,918 (54.2%) received sugammadex. Sugammadex was associated with a significantly lower incidence of overall PONV (15.8% vs. 17.7%; odds ratio, 0.87; 95% confidence interval [CI], 0.79-0.97; P = 0.010) after sIPTW. In conclusion, compared with neostigmine/glycopyrrolate, sugammadex use has a lower risk of PONV during the first 24 h following general anesthesia.

Intraoperative Fascial Plane Blocks Facilitate Earlier Tracheal Extubation and Intensive Care Unit Discharge After Cardiac Surgery: A Retrospective Cohort Analysis

OBJECTIVES

Novel fascial plane blocks may allow early tracheal extubation and discharge from the intensive care unit (ICU). The present study primarily aimed to determine whether fascial plane blocks, in comparison with intravenous analgesia alone, significantly shortened tracheal extubation times in patients undergoing cardiac surgery. The secondary objectives were to compare each block's performance with that of intravenous analgesia alone in terms of the individual tracheal extubation time and length of ICU stay.

DESIGN

Retrospective observational study.

SETTING

Single-center study.

PARTICIPANTS

Patients who underwent cardiac surgery between 2018 and 2019 were identified from a prospective clinical registry. After obtaining ethics approval, the clinical and electronic records of patients undergoing cardiac surgery in 2018 were analyzed. Data of patients receiving fascial plane blocks (erector spinae plane [ESP], pectoral plane I and II [PECs], and serratus anterior plane [SAP] blocks) with intravenous analgesia were compared with those of patients receiving only intravenous analgesia. A propensity score (PS) model was used to control for differences in the baseline characteristics. Adjusted p < 0.05 was considered statistically significant.

MEASUREMENTS AND MAIN RESULTS

Of the 589 patients screened, 532 met the inclusion criteria; 404 received a fascial plane block. After PS matching, weighted linear regression revealed that by receiving a block, the predicted extubation time difference was 9.29 hours (b coefficient; 95% CI: -11.98, -6.60; p = 0.022). Similar results were obtained using PS weighting, with a reduction of 7.82 hours (b coefficient; 95% CI: -11.89, -3.75; p < 0.001) in favor of the block. In the fascial-plane-block group, ESP block achieved the best performance. The length of ICU stay decreased by 1.1 days (b coefficient; 95% CI: -1.43, -0.79; p = 0.0001) in the block group. No complications were reported.

CONCLUSIONS

Fascial plane block is associated with reduced extubation times and lengths of ICU stay. ESP block achieved the best performance, followed by PECs and SAP blocks. After PS matching, only ESP block reduced the extubation time.

Determining the impact of ex-vivo lung perfusion on hospital costs for lung transplantation: A retrospective cohort study

INTRODUCTION

Ex-vivo lung perfusion (EVLP) has improved organ utilization for lung transplantation, but it is not yet known whether the benefits of this technology offset its additional costs. We compared the institutional costs of lung transplantation before vs after EVLP was available to identify predictors of costs and determine the health-economic impact of EVLP.

METHODS

We performed a retrospective, before-after, propensity-score weighted cohort study of patients wait-listed for lung transplant at University Health Network (UHN) in Ontario, Canada, between January 2005 and December 2019 using institutional administrative data. We compared costs, in 2019 Canadian Dollars ($), between patients referred for transplant before EVLP was available (Pre-EVLP) to after (Modern EVLP). Cumulative costs were estimated using a novel application of multistate survival models. Predictors of costs were identified using weighted log-gamma generalized linear regression.

RESULTS

A total of 1,199 patients met inclusion criteria (352 Pre-EVLP; 847 Modern EVLP). Mean total costs for the transplant hospitalization were $111,878 ($94,123-$130,767) in the Pre-EVLP era and $110,969 ($87,714-$136,000) in the Modern EVLP era. Cumulative five-year costs since referral were $278,777 ($82,575-$298,135) in the Pre-EVLP era and $293,680 ($252,832-$317,599) in the Modern EVLP era. We observed faster progression to transplantation when EVLP was available. EVLP availability was not a predictor of waitlist (cost ratio [CR] 1.04 [0.81-1.37]; p = 0.354) or transplant costs (CR 1.02 [0.80-1.29]; p = 0.425) but was associated with lower costs during posttransplant years 1&2 (CR 0.75 [0.58-1.06]; p = 0.05) and posttransplant years 3+ (CR 0.43 [0.26-0.74]; p = 0.001).

CONCLUSIONS

At our center, EVLP availability was associated with faster progression to transplantation at no significant marginal cost.

Derivation and Validation of Clinical Phenotypes of the Cardiopulmonary Bypass-Induced Inflammatory Response

BACKGROUND

Precision medicine aims to change treatment from a "one-size-fits-all" approach to customized therapies based on the individual patient. Applying a precision medicine approach to a heterogeneous condition, such as the cardiopulmonary bypass (CPB)-induced inflammatory response, first requires identification of homogeneous subgroups that correlate with biological markers and postoperative outcomes. As a first step, we derived clinical phenotypes of the CPB-induced inflammatory response by identifying patterns in perioperative clinical variables using machine learning and simulation tools. We then evaluated whether these phenotypes were associated with biological response variables and clinical outcomes.

METHODS

This single-center, retrospective cohort study used Cleveland Clinic registry data from patients undergoing cardiac surgery with CPB from January 2010 to March 2020. Biomarker data from a subgroup of patients enrolled in a clinical trial were also included. Patients undergoing emergent surgery, off-pump surgery, transplantation, descending thoracoabdominal aortic surgery, and planned ventricular assist device placement were excluded. Preoperative and intraoperative variables of patient baseline characteristics (demographics, comorbidities, and laboratory data) and perioperative data (procedural data, CPB duration, and hemodynamics) were analyzed to derive clinical phenotypes using K-means-based consensus clustering analysis. Proportion of ambiguously clustered was used to assess cluster size and optimal cluster numbers. After clusters were formed, we summarized perioperative profiles, inflammatory biomarkers (eg, interleukin [IL]-6 and IL-8), kidney biomarkers (eg, urine neutrophil gelatinase-associated lipocalin [NGAL] and IL-18), and clinical outcomes (eg, mortality and hospital length of stay). Pairwise standardized difference was reported for all summarized variables.

RESULTS

Of 36,865 eligible cardiac surgery cases, 25,613 met inclusion criteria. Cluster analysis derived 3 clinical phenotypes: α, β, and γ. Phenotype α (n = 6157 [24%]) included older patients with more comorbidities, including heart and kidney failure. Phenotype β (n = 10,572 [41%]) patients were younger and mostly male. Phenotype γ (n = 8884 [35%]) patients were 58% female and had lower body mass index (BMI). Phenotype α patients had worse outcomes, including longer hospital length of stay (mean = 9 days for α versus 6 for both β [absolute standardized difference {ASD} = 1.15] and γ [ASD = 1.08]), more kidney failure, and higher mortality. Inflammatory biomarkers (IL-6 and IL-8) and kidney injury biomarkers (urine NGAL and IL-18) were higher with the α phenotype compared to β and γ immediately after surgery.

CONCLUSIONS

Deriving clinical phenotypes that correlate with response biomarkers and outcomes represents an initial step toward a precision medicine approach for the management of CPB-induced inflammatory response and lays the groundwork for future investigation, including an evaluation of the heterogeneity of treatment effect.

Epidemiology, risk factors and outcomes of norepinephrine use in cardiac surgery with cardiopulmonary bypass: a multicentric prospective study

BACKGROUND

The present study was designed to describe the prevalence of norepinephrine use, the factors associated with its use, and the incidence of postoperative complications according to norepinephrine use, in patients undergoing cardiac surgery with cardiopulmonary bypass.

METHOD

We performed a prospective, multicenter, observational study in 4 University-affiliated medico-surgical cardiovascular units. We analyzed all patients treated with cardiac surgery after excluding pre-ECMO surgery, LVAD implantation, heart transplantation and intra-operative hemorrhage.

RESULTS

Of 9316 patients screened during the study period, 2862 were included and 2510 were analyzed. Among them, 1549 (61%) were treated with norepinephrine with a median maximal dose of 0.11 [0.06-0.2] μg.kg^-1.min^-1 and a median duration of 10 h [2-24]. Norepinephrine was most often started in the operating room before cardiopulmonary bypass. The multiple regression logistic analysis identified several modifiable (haematocrit, maintenance of beta-blocker, cardiopulmonary bypass time, glucose-insulin-potassium, Custodiol cardioplegia, Delnido cardioplegia, and fibrinogen transfusion) and non-modifiable factors (age, ASA score, chronic high blood pressure, coronary disease, dyslipidemia, right ventricular dysfunction, left ventricular dysfunction, active endocarditis, and valvular aortic surgery) associated with norepinephrine use. Mortality, morbidity (neurological and renal complications, death) and length of stay in the ICU were higher in patients treated with norepinephrine.

CONCLUSION

Norepinephrine is often used in cardiac surgical patients but for <24 h with a low dose. Many preoperative and surgical factors are associated with norepinephrine use. Patients supported by norepinephrine have a higher incidence of major postoperative events.

Real-world outcomes of different lines and sequences of treatment in BRAF-positive advanced melanoma patients

The objective of this study is to compare efficacy with different treatment sequences and lines of treatment among BRAF V600 mutated (BRAF+) advanced melanoma patients with immunotherapies (IO) and targeted therapies (TT) using real-world data. This was a retrospective cohort study using the Novartis BRAF+ meLanoma patients ObsErvational database, the harmonized customized data from Flatiron and ConcertAI. The study included BRAF+ advanced unresectable melanoma patients treated with first-line (1L) IO or TT between 1 January 2014 and 31 May 2020. Patient characteristics and treatment patterns were described. Kaplan-Meier curves and propensity score-adjusted Cox models were used for analyzing progression-free survival (PFS) and overall survival (OS). A total of 1961 patients were included, of which, 57.2% received IO and 42.8% received TT on 1L therapy. Overall, 603 patients initiated a 2L therapy: 56.2% IO and 43.8% TT. Regardless of treatment sequence, patients progressed at a relatively similar rate with no significant difference between groups (median PFS: 12.9 months for 1L TT/2L IO and 13.1 months for 1L IO/2L TT; HR, 0.84; P = 0.137). The 2-year OS rate was also similar with 1L TT/2L IO and 1L IO/2L TT (78% vs. 80%; HR, 1.09; P = 0.730). PFS was worse on 2L therapy compared with 1L (median 4.7 vs. 6.5 months). Efficacy on 2L therapy was poor compared with 1L. Among patients who received 2L therapy, regardless of treatment sequences, outcomes were comparable between 1L TT/2L IO and 1L IO/2L TT in this study that reflects real-world experiences beyond clinical trial selective eligibility criteria.

Hypoventilation in the PACU is associated with hypoventilation in the surgical ward: Post-hoc analysis of a randomized clinical trial

OBJECTIVE

To evaluate the association between early postoperative hypoventilation in the last hour of the post-anesthesia care unit (PACU) stay and hypoventilation during the rest of the first 48 postoperative hours in the surgical ward.

DESIGN

Sub-analysis of a clinical trial.

SETTING

PACU and surgical wards of a single medical center.

PATIENTS

Adults having abdominal surgery under general anesthesia.

INTERVENTIONS

Monitoring with a respiratory volume monitor from admission to PACU until the earlier of 48 h after surgery or discharge.

MEASUREMENTS

The exposure was having at least one low minute-ventilation (MV) event during the last hour of PACU stay, defined as MV lower than 40% the predicted value lasting at least 1 min. The primary outcome was low MV events lasting at least 2 min during the rest of the first 48 postoperative hours, while in the surgical ward. The secondary outcome was the rate of low MV events per monitored hour.

MAIN RESULTS

Data of 292 patients were analyzed, of which 20 (6.8%) patients had a low MV event in PACU. Low MV events in the surgical ward were found in 81 (28%) patients. All patients who had low MV events in PACU had events again in the ward, while 61/272 (22%) had an event in the ward but not in PACU. The incidence rate of low MV events per hour was 24 (95% CI: 13, 46) among patients having an event in the PACU, and 2 (1, 4) among those who did not.

CONCLUSIONS

In adults recovering from abdominal surgery, events of hypoventilation during the first postoperative hour are associated with similar events during the rest of the first 48 postoperative hours, with positive predictive value approaching 100%. Sixty-one patients had ward hypoventilation that was not preceded by hypoventilation in PACU.

Strong instrumental variables biased propensity scores in comparative effectiveness research: A case study in oncology

BACKGROUND AND OBJECTIVES

Some medications require specific medical procedures in the weeks before their start. Such procedures may meet the definition of instrumental variables (IVs). We examined how they may influence treatment effect estimation in propensity score (PS)-adjusted comparative studies, and how to remedy.

STUDY DESIGN AND SETTING

Different covariate assessment periods (CAPs) did and did not include the month preceding treatment start were used to compute PS in the French claims database (Sytème National des Données de Santé-SNDS), and 1:1 match patients with metastatic castration resistant prostate cancer initiating abiraterone acetate or docetaxel. The 36-month survival was assessed.

RESULTS

Among 1, 213 docetaxel and 2, 442 abiraterone initiators, the PS distribution resulting from the CAP [-12; 0 months] distinctly separated populations (c = 0.93; 273 matched pairs). The CAPs [-12;-1 months] identified 765 pairs (c = 0.81). Strong docetaxel treatment predictors during the month before treatment start were implantable delivery systems (1% vs. 59%), which fulfilled IV conditions. The 36-month survival was not meaningfully different under the [-12; 0 months] CAP but differed by 10% points (38% vs. 28%) after excluding month -1.

CONCLUSION

In the setting of highly predictive pretreatment procedures, excluding the immediate pre-exposure time from the CAP will reduce the risk of including potential IVs in PS models and may reduce bias.

Preoperative β-Blocker Therapy and Stroke or Major Adverse Cardiac Events in Major Abdominal Surgery: A Retrospective Cohort Study

BACKGROUND

Perioperative β-blocker therapy has been associated with increased risk of stroke. However, the association between β-blocker initiation before the day of surgery and the risk of stroke is unknown. The authors hypothesized there would be no association between preoperative β-blocker initiation within 60 days of surgery or chronic β-blockade (more than 60 days) and the risk of stroke in patients undergoing major abdominal surgery.

METHODS

Data on elective major abdominal surgery were obtained from the IBM (USA) Truven Health MarketScan 2005 to 2015 Commercial and Medicare Supplemental Databases. Patients were stratified by β-blocker dispensing exposure: (1) β-blocker-naïve, (2) preoperative β-blocker initiation within 60 days of surgery, and (3) chronic β-blocker dispensing (more than 60 days). The authors compared in-hospital stroke and major adverse cardiac events between the different β-blocker therapy exposures.

RESULTS

There were 204,981 patients who underwent major abdominal surgery. β-Blocker exposure was as follows: perioperative initiation within 60 days of surgery for 4,026 (2.0%) patients, chronic β-blocker therapy for 45,424 (22.2%) patients, and β-blocker-naïve for 155,531 (75.9%) patients. The unadjusted frequency of stroke for patients with β-blocker initiation (0.4%, 17 of 4,026) and chronic β-blocker therapy (0.4%, 171 of 45,424) was greater than in β-blocker-naïve patients (0.2%, 235 of 155,531; P < 0.001). After propensity score weighting, patients initiated on a β-blocker within 60 days of surgery (odds ratio, 0.90; 95% CI, 0.31 to 2.04; P = 0.757) or on chronic β-blocker therapy (odds ratio, 0.86; 95% CI, 0.65 to 1.15; P = 0.901) demonstrated similar stroke risk compared to β-blocker-naïve patients. Patients on chronic β-blocker therapy demonstrated lower adjusted risk of major adverse cardiac events compared to β-blocker-naïve patients (odds ratio, 0.81; 95% CI, 0.72 to 0.91; P = 0.007), despite higher unadjusted absolute event rate (2.6% [1,173 of 45,424] vs. 0.6% [872 of 155,531]).

CONCLUSIONS

Among patients undergoing elective major abdominal surgery, the authors observed no association between preoperative β-blocker initiation within 60 days of surgery or chronic β-blocker therapy and stroke.

EDITOR’S PERSPECTIVE

Nalbuphine May Be Superior to Sufentanil in Relieving Postcesarean Uterine Contraction Pain in Multiparas: A Retrospective Cohort Study

Purpose

Postcesarean pain remains a major complaint from puerperium women who have undergone cesarean section, especially uterine contraction induced visceral pain. The optimal opioid for pain relief after cesarean section (CS) is still unclear. The goal of this study was to compare the analgesic effect of Nalbuphine to Sufentanil in patients who underwent CS.

Patients and Methods

In this single-center retrospective cohort study, we included patients who received Nalbuphine or Sufentanil Patient-Controlled Intravenous Analgesia (PCIA) after CS between 1 January 2018 and 30 November 2020. Data on a Visual Analog Scale (VAS) at uterine contraction, at rest, and at movement, analgesic consumption, and side effects were collected. We performed logistic regression to identify predictors of severe uterine contraction pain.

Results

A total of 674 patients were identified in the unmatched cohort, and 612 patients in the matched one. Compared to the Sufentanil group, lower VAS-contraction was recorded in the Nalbuphine group in both the unmatched and matched cohorts, the mean difference (MD) on POD1 was 0.35 (95% CI: 0.17 to 0.54, p<0.001) and 0.28 (95% CI: 0.08 to 0.47, p<0.001), respectively, and the MD of POD2 was 0.12 (95% CI: 0.03 to 0.40, P=0.019) and 0.12 (95% CI: 0.03 to 0.41, P=0.026), respectively. On POD1 but not POD2, VAS-movement was lower in the Nalbuphine group as compared to the Sufentanil group. No difference was found between VAS-rest on POD1 and POD2 in both unmatched and matched cohorts. Less analgesic consumption, and side effects were recorded in the Nalbuphine group. Logistic regression indicated that multipara and analgesic consumption were risk factors for severe uterine contraction pain. In subgroup analysis, VAS-contraction was meaningfully reduced in the Nalbuphine group compared with the Sufentanil group in multipara patients, but not primiparas.

Conclusion

Compared to Sufentanil, Nalbuphine may provide better analgesia on uterine contraction pain. The superior analgesia may only exhibit in multiparas.