Can routine perioperative haemodynamic parameters predict postoperative morbidity after major surgery?

Development and validation of a predictive model for PACU hypotension in elderly patients undergoing sedated gastrointestinal endoscopy

BACKGROUND

Hypotension, characterized by abnormally low blood pressure, is a frequently observed adverse event in sedated gastrointestinal endoscopy procedures. Although the examination time is typically short, hypotension during and after gastroscopy procedures is frequently overlooked or remains undetected. This study aimed to construct a risk nomogram for post-anesthesia care unit (PACU) hypotension in elderly patients undergoing sedated gastrointestinal endoscopy.

METHODS

This study involved 2919 elderly patients who underwent sedated gastrointestinal endoscopy. A preoperative questionnaire was used to collect data on patient characteristics; intraoperative medication use and adverse events were also recorded. The primary objective of the study was to evaluate the risk of PACU hypotension in these patients. To achieve this, the least absolute shrinkage and selection operator (LASSO) regression analysis method was used to optimize variable selection, involving cyclic coordinate descent with tenfold cross-validation. Subsequently, multivariable logistic regression analysis was applied to build a predictive model using the selected predictors from the LASSO regression. A nomogram was visually developed based on these variables. To validate the model, a calibration plot, receiver operating characteristic (ROC) curve, and decision curve analysis (DCA) were used. Additionally, external validation was conducted to further assess the model's performance.

RESULTS

The LASSO regression analysis identified predictors associated with an increased risk of adverse events during surgery: age, duration of preoperative water abstinence, intraoperative mean arterial pressure (MAP) <65 mmHg, decreased systolic blood pressure (SBP), and use of norepinephrine (NE). The constructed model based on these predictors demonstrated moderate predictive ability, with an area under the ROC curve of 0.710 in the training set and 0.778 in the validation set. The DCA indicated that the nomogram had clinical applicability when the risk threshold ranged between 20 and 82%, which was subsequently confirmed in the external validation with a range of 18-92%.

CONCLUSION

Incorporating factors such as age, duration of preoperative water abstinence, intraoperative MAP <65 mmHg, decreased SBP, and use of NE in the risk nomogram increased its usefulness for predicting PACU hypotension risk in elderly patient undergoing sedated gastrointestinal endoscopy.

Association Between Mobilization and Composite Postoperative Complications Following Major Elective Surgery

Importance

Mobilization after surgery is a key component of Enhanced Recovery after Surgery (ERAS) pathways.

Objective

To evaluate the association between mobilization and a collapsed composite of postoperative complications in patients recovering from major elective surgery as well as hospital length of stay, cumulative pain scores, and 30-day readmission rates.

Design, Setting, and Participants

This retrospective observational study conducted at a single quaternary US referral center included patients who had elective surgery between February 2017 and October 2020. Mobilization was assessed over the first 48 postoperative hours with wearable accelerometers, and outcomes were assessed throughout hospitalization. Patients who had elective surgery lasting at least 2 hours followed by at least 48 hours of hospitalization were included. A minimum of 12 hours of continuous accelerometer monitoring was required without missing confounding variables or key data. Among 16 203 potential participants, 8653 who met inclusion criteria were included in the final analysis. Data were analyzed from February 2017 to October 2020.

Exposures

Amount of mobilization per hour for 48 postoperative hours.

Outcomes

The primary outcome was a composite of myocardial injury, ileus, stroke, venous thromboembolism, pulmonary complications, and all-cause in-hospital mortality. Secondary outcomes included hospital length of stay, cumulative pain scores, and 30-day readmission.

Results

Of 8653 included patients (mean [SD] age, 57.6 [16.0] years; 4535 [52.4%] female), 633 (7.3%) experienced the primary outcome. Mobilization time was a median (IQR) of 3.9 (1.7-7.8) minutes per monitored hour overall, 3.2 (0.9-7.4) in patients who experienced the primary outcome, and 4.1 (1.8-7.9) in those who did not. There was a significant association between postoperative mobilization and the composite outcome (hazard ratio [HR], 0.75; 95% CI, 0.67-0.84; P < .001) for each 4-minute increase in mobilization. Mobilization was associated with an estimated median reduction in the duration of hospitalization by 0.12 days (95% CI, 0.09-0.15; P < .001) for each 4-minute increase in mobilization. The were no associations between mobilization and pain score or 30-day readmission.

Conclusions and Relevance

In this study, mobilization measured by wearable accelerometers was associated with fewer postoperative complications and shorter hospital length of stay.

Incidence of intraoperative hypotension during non-cardiac surgery in community anesthesia practice: a retrospective observational analysis

BACKGROUND

Intraoperative hypotension (IOH) is well-described in the academic setting but not in community practice. IOH is associated with risk of postoperative morbidity and mortality. This is the first report of IOH in the community setting using the IOH measure definition from the Centers for Medicare and Medicaid Services Merit-based Incentive Payment System program.

OBJECTIVES

To describe the incidence of IOH in the community setting; assess variation in IOH by patient-, procedure-, and facility-level characteristics; and describe variation in risk-adjusted IOH across clinicians.

METHODS

Design Cross-sectional descriptive analysis of retrospective data from anesthesia records in 2020 and 2021. Setting Forty-five facilities affiliated with two large anesthesia providers in the USA. Participants Patients aged 18 years or older having non-emergent, non-cardiac surgery under general, neuraxial, or regional anesthesia. Cases were excluded based on criteria for the IOH measure: baseline mean arterial pressure (MAP) below 65 mmHg prior to anesthesia induction; American Society of Anesthesiologists (ASA) physical status classification of I, V, or VI; monitored anesthesia care only; deliberate induced hypotension; obstetric non-operative procedures; liver or lung transplant; cataract surgery; non-invasive gastrointestinal cases. Main outcomes IOH, using four definitions. Primary definition: binary assessment of whether the case had MAP < 65 mmHg for 15 min or more. Secondary definitions: total number of minutes of MAP < 65 mmHg, total area under MAP of 65 mmHg, time-weighted average MAP < 65 mmHg.

RESULTS

Among 127,095 non-emergent, non-cardiac cases in community anesthesia settings, 29% had MAP < 65 mmHg for at least 15 min cumulatively, with an overall mean of 12.4 min < 65 mmHg. IOH was slightly more common in patients who were younger, female, and ASA II (versus III or IV); in procedures that were longer and had higher anesthesia base units; and in ambulatory surgery centers. Incidence of IOH varied widely across individual clinicians in both unadjusted and risk-adjusted analyses.

CONCLUSION

Intraoperative hypotension is common in community anesthesia practice, including among patients and settings typically considered "low risk." Variation in incidence across clinicians remains after risk-adjustment, suggesting that IOH is a modifiable risk worth pursuing in quality improvement initiatives.

The burden of perioperative hypertension/hypotension: A systematic review

Study objective

Our goal is to review the outcomes of acute hypertensive/hypotensive episodes from articles published in the past 10 years that assessed the short- and long-term impact of acute hypertensive/hypotensive episodes in the perioperative setting.

Methods

We conducted a systematic peer review based upon PROSPERO and Cochrane Handbook protocols. The following study characteristics were collected: study type, author, year, population, sample size, their definition of acute hypertension, hypotension or other measures, and outcomes (probabilities, odds ratio, hazard ratio, and relative risk) and the p-values; and they were classified according to the type of surgery (cardiac and non-cardiac).

Results

A total of 3,680 articles were identified, and 66 articles fulfilled the criteria for data extraction. For the perioperative setting, the number of articles varies by outcome: 20 mortality, 16 renal outcomes, 6 stroke, 7 delirium and 34 other outcomes. Hypotension was reported to be associated with mortality (OR 1.02–20.826) as well as changes from the patient’s baseline blood pressure (BP) (OR 1.02–1.36); hypotension also had a role in the development of acute kidney injury (AKI) (OR 1.03–14.11). Postsurgical delirium was found in relation with BP lability (OR 1.018–1.038) and intra- and postsurgical hypotension (OR 1.05–1.22), and hypertension (OR 1.44–2.34). Increased OR (37.67) of intracranial hemorrhage was associated to postsurgical systolic BP >130 mmHg. There was a wide range of additional diverse outcomes related to hypo-, hypertension and BP lability.

Conclusions

The perioperative management of BP influences short- and long-term effects of surgical procedures in cardiac and non-cardiac interventions; these findings support the burden of BP fluctuations in this setting.

Monitored Anesthesia Care and Soft-Tissue Infiltration With Local Anesthesia: An Anesthetic Option for High-Risk Patients With Hip Fractures

OBJECTIVES

To examine the feasibility of a novel anesthetic option for hip fracture fixation with short cephalomedullary nails.

DESIGN

Retrospective cohort study.

SETTING

The study setting involved an urban, academic Level 1 trauma center, a tertiary care academic medical center, and an orthopaedic specialty hospital.

PATIENTS/PARTICIPANTS

Twenty recent and 40 risk-matched (1:1:1 by anesthesia type) historical hip fracture patients were included in the study.

INTERVENTION

All patients with an OTA/AO 31.A1-3 intertrochanteric hip fracture presenting from October 1, 2019 to March 31, 2020 treated with a short cephalomedullary nail underwent a new intraoperative anesthesia protocol using monitored anesthesia care (MAC) and soft-tissue infiltration with local anesthesia (STILA).

MAIN OUTCOME MEASUREMENTS

Intraoperative measures, postoperative pain scores, narcotic and acetaminophen use, hospital quality measures, and inpatient cost.

RESULTS

A total of 60 patients (20 each: MAC, general, and spinal) were identified. There were differences among the groups regarding mean minimum and maximum intraoperative heart rate with MAC-STILA protocol demonstrating the best maintenance of normal heart rate parameters (60-100 beats per minute). For the first 3 hours postoperatively, MAC-STILA patients reported consistently lower pain scores (visual analog scale <1) than spinal or general patients (visual analog scale > 1). Through 48 hours postoperatively, MAC-STILA narcotic usage was similar to that of the spinal cohort and approximately 5 times less than the general cohort. There were no differences in procedural time, length of stay, minor or major complications, inpatient and 30-day mortality, or 30-day readmissions, or postoperative ambulatory distance. There was no difference in inpatient cost among cohorts.

CONCLUSIONS

This feasibility study demonstrates safety for the MAC-STILA protocol with comparison to spinal and general anesthesia. The MAC-STILA protocol is a viable option for treatment of OTA/AO 13.A1-3 intertrochanteric fractures with a short cephalomedullary nail and may be the preferred method for patients with severe medical comorbidities or relative contraindications to general and/or spinal anesthesia.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of Levels of Evidence.

Treatment threshold for intra-operative hypotension in clinical practice-a prospective cohort study in older patients in the UK

Intra-operative hypotension frequently complicates anaesthesia in older patients and is implicated in peri-operative organ hypoperfusion and injury. The prevalence and corresponding treatment thresholds of hypotension are incompletely described in the UK. This study aimed to identify prevalence of intra-operative hypotension and its treatment thresholds in UK practice. Patients aged ≥ 65 years were studied prospectively from 196 UK hospitals within a 48-hour timeframe. The primary outcome was the incidence of hypotension (mean arterial pressure <65 mmHg; systolic blood pressure reduction >20%; systolic blood pressure <100 mmHg). Secondary outcomes included the treatment blood pressure threshold for vasopressors; incidence of acute kidney injury; myocardial injury; stroke; and in-hospital mortality. Additionally, anaesthetists providing care for included patients were asked to complete a survey assessing their intended treatment thresholds for hypotension. Data were collected from 4750 patients. Hypotension affected 61.0% of patients when defined as mean arterial pressure <65 mmHg, 91.3% of patients had >20% reduction in systolic blood pressure from baseline and 77.5% systolic blood pressure <100 mmHg. The mean (SD) blood pressure triggering vasopressor therapy was mean arterial pressure 64.2 (11.6) mmHg and the mean (SD) stated intended treatment threshold from the survey was mean arterial pressure 60.6 (9.7) mmHg. A composite adverse outcome of myocardial injury, kidney injury, stroke or death affected 345 patients (7.3%). In this representative sample of UK peri-operative practice, the majority of older patients experienced intra-operative hypotension and treatment was delivered below suggested thresholds. This highlights both potential for intra-operative organ injury and substantial opportunity for improving treatment of intra-operative hypotension.