Improving preoperative prediction of surgery duration

BACKGROUND

Operating rooms (ORs) are one of the costliest units in a hospital, therefore the cumulative consequences of any kind of inefficiency in OR management lead to a significant loss of revenue for the hospital, staff dissatisfaction, and patient care disruption. One of the possible solutions to improving OR efficiency is knowing a reliable estimate of the duration of operations. The literature suggests that the current methods used in hospitals, e.g., a surgeon's estimate for the given surgery or taking the average of only five previous records of the same procedure, have room for improvement.

METHODS

We used over 4 years of elective surgery records (n = 52,171) from one of the major metropolitan hospitals in Australia. We developed robust Machine Learning (ML) approaches to provide a more accurate prediction of operation duration, especially in the absence of surgeon's estimation. Individual patient characteristics and historic surgery information attributed to medical records were used to train predictive models. A wide range of algorithms such as Extreme Gradient Boosting (XGBoost) and Random Forest (RF) were tested for predicting operation duration.

RESULTS

The results show that the XGBoost model provided statistically significantly less error than other compared ML models. The XGBoost model also reduced the total absolute error by 6854 min (i.e., about 114 h) compared to the current hospital methods.

CONCLUSION

The results indicate the potential of using ML methods for reaching a more accurate estimation of operation duration compared to current methods used in the hospital. In addition, using a set of realistic features in the ML models that are available at the point of OR scheduling enabled the potential deployment of the proposed approach.

Outcomes following perioperative red blood cell transfusion in patients undergoing elective major abdominal surgery: a systematic review and meta-analysis

BACKGROUND

Perioperative red blood cell transfusion is a double-edged sword for surgical patients. While transfusion of red cells can increase oxygen delivery by increasing haemoglobin levels, its impact on short- and long-term postoperative outcomes, particularly in patients undergoing elective major abdominal surgery, is unclear.

METHODS

We conducted a systematic review and meta-analysis on the effect of perioperative blood transfusions on postoperative outcomes in elective major abdominal surgery. PubMed, Cochrane, and Scopus databases were searched for studies with data collected between January 1, 2000 and June 6, 2020. The primary outcome was short-term mortality, including all-cause 30-day or in-hospital mortality. Secondary outcomes included long-term all-cause mortality, any morbidity, infectious complications, overall survival, and recurrence-free survival. No randomised controlled trials were found. Thirty-nine observational studies were identified, of which 37 were included in the meta-analysis.

RESULTS

Perioperative blood transfusion was associated with short-term all-cause mortality (odds ratio [OR] 2.72, 95% confidence interval [CI] 1.89-3.91, P<0.001), long-term all-cause mortality (hazard ratio 1.35, 95% CI 1.09-1.67, P=0.007), any morbidity (OR 2.18, 95% CI 1.81-2.64, P<0.001), and infectious complications (OR 1.90, 95% CI 1.60-2.26, P<0.001). Perioperative blood transfusion remained associated with short-term mortality in the sensitivity analysis after excluding studies that did not control for preoperative anaemia (OR 2.27, 95% CI 1.59-3.24, P<0.001).

CONCLUSIONS

Perioperative blood transfusion in patients undergoing elective major abdominal surgery is associated with poorer short- and long-term postoperative outcomes. This highlights the need to implement patient blood management strategies to manage and preserve the patient's own blood and reduce the need for red blood cell transfusion.

TRIAL REGISTRATION

PROSPERO (CRD42021254360).

Perioperative Management of Patients with Craniomaxillofacial Trauma

Successful surgical management of patients with facial fractures requires a detailed preoperative evaluation and postoperative management that differs from elective surgical patients. This review presents evidence-based recommendations from the surgical and anesthesiology literature that address many of the clinical questions that arise during the perioperative management of this group of patients. Surgeons and anesthesiologists must work together at numerous points and make joint decisions, especially where airway and pain management challenges may arise. The multidisciplinary nature of the decision-making process is emphasized.

Non-English Primary Language: A Growing Population's Access to Cholecystectomy

OBJECTIVE

To examine access to cholecystectomy and postoperative outcomes among non-English primary-speaking patients.

BACKGROUND

The population of U.S. residents with limited English proficiency is growing. Language affects health literacy and is a well-recognized barrier to health care in the United States of America. Historically marginalized communities are at greater risk of requiring emergent gallbladder operations. However, little is known about how primary language affects surgical access and outcomes of common surgical procedures, such as cholecystectomy.

METHODS

We conducted a retrospective cohort study of adult patients after receipt of cholecystectomy in Michigan, Maryland, and New Jersey utilizing the Healthcare Cost and Utilization Project State Inpatient Database and State Ambulatory Surgery and Services Database (2016-2018). Patients were classified by primary spoken language: English or non-English. The primary outcome was admission type. Secondary outcomes included operative setting, operative approach, in-hospital mortality, postoperative complications, and length of stay. Multivariable logistics and Poisson regression were used to examine outcomes.

RESULTS

Among 122,013 patients who underwent cholecystectomy, 91.6% were primarily English speaking and 8.4% were non-English primary language speaking. Primary non-English speaking patients had a higher likelihood of emergent/urgent admissions (odds ratio: 1.22, 95% CI: 1.04-1.44, P = 0.015) and a lower likelihood of having an outpatient operation (odds ratio: 0.80, 95% CI: 0.70-0.91, P = 0.0008). There was no difference in the use of a minimally invasive approach or postoperative outcomes based on the primary language spoken.

CONCLUSIONS

Non-English primary language speakers were more likely to access cholecystectomy through the emergency department and less likely to receive outpatient cholecystectomy. Barriers to elective surgical presentation for this growing patient population need to be further studied.

Evaluating opioid prescribing patterns following discharge from elective surgical procedures: a worrying trend during the 'opioid crisis' - an audit of elective surgical procedures

BACKGROUND

The 'opioid crisis' has reached epidemic proportions globally. Importantly, 30% of opioid dependency stem from opioids obtained on hospital discharge prescriptions.

AIM

The aim of this study is to evaluate opioid prescription patterns on discharge of post-operative patients in an Irish Hospital.

METHODS

A retrospective cohort study was undertaken in a single institution during the 5 year eligibility period (January 2017-October 2021). Comparisons in opioid prescription patterns following minor (inguinal hernia repair (IHR), intermediate (laparoscopic cholecystectomy (LC)) and major (colonic resection (CR)) were made. Descriptive statistics were performed using SPSS version 26.0 RESULTS: In total, 300 patients were included in this study with mean age 59.6 years (range: 20-92). Of these, 112 patients underwent IHR (37.3%), 116 patients underwent LC (38.7%), and 72 patients underwent CR (24.0%). The mean age at diagnosis was 61 years, 53 years and 58 years for IHR, LC and CR, respectively (P < 0.001). Patients undergoing CR were more likely to have greater comorbidity burden (3.1 vs. 1.2 (IHR) vs. 1.8 (LC) respectively (P = 0.030). On discharge, 27.8% of CR patients received opioids (20/72) compared to 24.1% of IHR (28/116) and 15.9% of LC (18/113) patients, respectively (P = 0.126).

CONCLUSION

We observed considerable variability in opioid prescribing patterns following minor, intermediate and major operations in our centre. Care is required when prescribing opioids in the post-operative setting, and opioid prescription guidelines are required to both tackle and prevent an escalation of this 'opioid crisis'.

Trends in usage of navigation and robotic assistance in elective spine surgeries: a study of 105,212 cases from 2007 to 2015

OBJECTIVE

Identify trends of navigation and robotic-assisted elective spine surgeries.

METHODS

Elective spine surgery patients between 2007 and 2015 in the Nationwide Inpatient Sample (NIS) were isolated by ICD-9 codes for Navigation [Nav] or Robotic [Rob]-Assisted surgery. Basic demographics and surgical variables were identified via chi-squared and t tests. Each system was analyzed from 2007 to 2015 for trends in usage.

RESULTS

Included 3,759,751 patients: 100,488 Nav; 4724 Rob. Nav were younger (56.7 vs 62.7 years), had lower comorbidity index (1.8 vs 6.2, all p < 0.05), more decompressions (79.5 vs 42.6%) and more fusions (60.3 vs 52.6%) than Rob. From 2007 to 2015, incidence of complication increased for Nav (from 5.8 to 21.7%) and Rob (from 3.3 to 18.4%) as well as 2-3 level fusions (from 50.4 to 52.5%) and (from 1.3 to 3.2%); respectively. Invasiveness increased for both (Rob: from 1.7 to 2.2; Nav: from 3.7 to 4.6). Posterior approaches (from 27.4 to 41.3%), osteotomies (from 4 to 7%), and fusions (from 40.9 to 54.2%) increased in Rob. Anterior approach for Rob decreased from 14.9 to 14.4%. Nav increased posterior (from 51.5% to 63.9%) and anterior approaches (from 16.4 to 19.2%) with an increase in osteotomies (from 2.1 to 2.7%) and decreased decompressions (from 73.6 to 63.2%).

CONCLUSIONS

From 2007 to 2015, robotic and navigation systems have been performed on increasingly invasive spine procedures. Robotic systems have shifted from anterior to posterior approaches, whereas navigation computer-assisted procedures have decreased in rates of usage for decompression procedures.

Association of Housing Status With Types of Operations and Postoperative Health Care Utilization

OBJECTIVE

To analyze the association between housing status and the nature of surgical care provided, health care utilization, and operational outcomes.

BACKGROUND

Unhoused patients have worse outcomes and higher health care utilization across multiple clinical domains. However, little has been published describing the burden of surgical disease in unhoused patients.

METHODS

We conducted a retrospective cohort study of 111,267 operations from 2013 to 2022 with housing status documented at a single, tertiary care institution. We conducted unadjusted bivariate and multivariate analyses adjusting for sociodemographic and clinical characteristics.

RESULTS

A total of 998 operations (0.8%) were performed for unhoused patients, with a higher proportion of emergent operations than housed patients (56% vs 22%). In unadjusted analysis, unhoused patients had longer length of stay (18.7 vs 8.7 days), higher readmissions (9.5% vs 7.5%), higher in-hospital (2.9% vs 1.8%) and 1-year mortality (10.1% vs 8.2%), more in-hospital reoperations (34.6% vs 15.9%), and higher utilization of social work, physical therapy, and occupational therapy services. After adjusting for age, sex, comorbidities, insurance status, and indication for operation, as well as stratifying by emergent versus elective operation, these differences went away for emergent operations.

CONCLUSIONS

In this retrospective cohort analysis, unhoused patients more commonly underwent emergent operations than their housed counterparts and had more complex hospitalizations on an unadjusted basis that largely disappeared after adjustment for patient and operative characteristics. These findings suggest issues with upstream access to surgical care that, when unaddressed, may predispose this vulnerable population to more complex hospitalizations and worse longer term outcomes.

The use of digital technologies to support home-based prehabilitation prior to major surgery: A systematic review

BACKGROUND

Prehabilitation is a multidimensional and multidisciplinary approach, to prepare patients for surgery, with the aim of improving postoperative outcomes. Worldwide, healthcare systems are facing challenges with a gap between demand and supply of healthcare services. Telehealth is seen as a solution for delivering sustainable and efficient treatments. The effect of providing prehabilitation using telehealth solutions is unclear.

OBJECTIVE

This systematic review investigated the existing literature regarding the effects and feasibility of technologies for remotely supporting home-based prehabilitation compared to standard care on pre- and postoperative outcomes in adults undergoing elective major surgery.

METHODS

A literature search identified relevant studies published between 1 January 2012 and December 2022 in PubMed, PsychInfo, Cinahl and the Cochrane Library. We included RCTs, feasibility and pilot studies. The quality of studies was evaluated using Cochrane's Risk of bias assessment and by narratively rating the certainty of evidence.

RESULTS

Six randomized controlled trials and 20 pilot/feasibility studies were included. The number and content of the interventions varied, depending on context and resources. Multiple approaches in the use of digital healthcare solutions were applied and the results highlight the potential of providing health services remotely.

CONCLUSION

The use of technologies to support remote home-based prehabilitation in patients undergoing elective major surgery is feasible and has high acceptability, though telehealth is a broad term and wide-ranging strategies are used. Digital technologies for supporting home-based prehabilitation are likely to play an essential role in future health care as resources are scarce and innovative solutions are needed.

Eligibility for elective surgery in patients recovering from mild COVID-19: A propensity-matched analysis

OBJECTIVE

To study the timing of surgery after a recent Omicron variant infection, to provide a reference for policymakers, clinicians, and patients.

METHODS

This single-center propensity-matched analysis was designed and reported according to the EQUATOR-STROBE guidelines. Patients recovering from COVID-19 infection were divided into three groups based on the period from disappearance of respiratory symptoms to surgery: ≤7 days, 8-14 days, and >14 days groups. Outcome measures included postoperative respiratory complications, vascular thrombosis, myocardial infarction, ischemic stroke, and mortality.

RESULTS

Between August 1 and December 31, 2022, 9023 surgical procedures were performed, of which 7490 surgeries met the inclusion criteria. Propensity matching resulted in a final cohort of 227 patients recovered from COVID-19 and 2043 SARS-CoV-2 negative patients. Compared with the SARS-CoV-2 negative group, the incidence of postoperative respiratory complications was significantly higher (15.91% vs. 6.71%, p = 0.028) only in the ≤7 days group. There were no statistically significant differences in the other 30-day outcomes between the SARS-CoV-2 negative and the three COVID-19 recovery groups.

CONCLUSIONS

Patients who have recovered from mild COVID-19 may be eligible for elective surgery at least 7 days after recovery, since they do not have an increased risk of postoperative complications or mortality within 30 days.

Quality of recovery in hospital and disability-free survival at three months after major abdominal surgery

BACKGROUND

The Quality of Recovery-15 (QoR-15) and 12-item World Health Organization Disability Assessment Schedule 2.0 scales are post-surgery patient-reported outcome measures. We aimed to evaluate the association between immediate in-hospital postoperative recovery and mid-term disability-free survival (DFS) after discharge.

METHODS

We conducted a prospective observational study at a university hospital and enrolled 260 patients aged ≥ 65 years with cancer who were undergoing elective major abdominal surgery. The association between poor postoperative recovery, defined as a QoR-15 score < 90 on postoperative day (POD) 2, and the DFS three months later was assessed using Fisher's exact test. The odds ratio of poor recovery on POD 2 to DFS was calculated using multiple logistic regression analysis adjusted for prominent factors (age, preoperative frailty, preoperative DFS, surgical duration, and intraoperative blood loss volume).

RESULTS

A total of 230 patients completed the 3-month follow-up. On POD 2, 27.3% of the patients (63/230) had poor recovery. A greater number of patients without poor recovery on POD 2 had DFS at three months after surgery (79.6%) than those with poor recovery (65.1%) (P = 0.026). The adjusted odds ratio of poor recovery on POD 2 to DFS at three months was 0.481 (95% CI [0.233, 0.994]).

CONCLUSIONS

Patients with poor recovery on POD 2 were less likely to have DFS three months after abdominal surgery. These findings may allow for early and effective interventions to be initiated based on each patient's condition after abdominal surgery.

Center-Level Variation in Failure to Rescue After Elective Adult Cardiac Surgery

BACKGROUND

There has been increasing emphasis on evaluation of failure to rescue (FTR) after major inpatient operations. The present study characterized center-level variation in FTR within a national cohort of patients undergoing elective cardiac operations.

METHODS

All adults undergoing elective coronary artery bypass grafting and/or valve operations were identified in the 2016-2019 Nationwide Readmissions Database. FTR was defined as in-hospital death after prolonged mechanical ventilation, stroke, reoperation, acute kidney injury requiring dialysis, sepsis, cardiac arrest or pulmonary embolism. Multi-level, mixed-effects regressions were used to model mortality, complications, and FTR. Centers with high hospital-specific rates of FTR (≥95th percentile) were identified and compared to others.

RESULTS

Of an estimated 454,506 patients included for analysis, 32,537 (7.2%) developed at least 1 complication, and 7669 (1.7%) died before discharge. Overall, 5370 (16.5%) patients experienced FTR. Compared with those who developed ≥1 complication but survived to discharge, FTR patients were significantly older, more commonly female, and had a greater burden of comorbidities as measured by the Elixhauser Comorbidity Index. Risk-adjusted, hospital-specific rates of mortality and FTR were moderately correlated (r = 0.64), mortality and complications were weakly associated (r = 0.16), and complications and FTR exhibited a very weak relationship (r = -0.02). Relative to others, centers with high rates of FTR had lower annual cardiac surgical volume (median 61 [interquartile range 33-133] vs 80 [interquartile range 43-149] cases/y, P = .019).

CONCLUSIONS

The present findings affirm prior work demonstrating a close link between variation in FTR and mortality, but not complications. Further study is necessary to delineate modifiable care pathways that mitigate FTR.

Enhanced recovery after brain tumor surgery: pilot protocol implementation in a large healthcare system

OBJECTIVE

Enhanced recovery after surgery (ERAS) protocols have been used in numerous specialties to improve the safety, efficiency, and cost of surgical interventions. Despite these successes, implementation of ERAS in cranial neurosurgery remains limited. In this study, a comprehensive ERAS protocol was implemented at two pilot sites within the Providence Health & Services system, and groundwork was laid for systemwide adoption.

METHODS

An enhanced recovery protocol was developed and implemented through an interdisciplinary team of clinicians, executive leadership, and clinical informatics professionals across preoperative, intraoperative, and postoperative domains. Outcomes including length of stay, discharge destination, and cost were collected through systemwide databases and compared with nonprotocolized sites.

RESULTS

During the study period, both pilot sites became top performers across the regional system in all evaluated metrics. The median length of stay for elective craniotomy at site 1 was reduced to 1.25 days, with a home discharge rate of > 90%. The cost per case at the pilot sites was nearly $7000 less on average than that of the nonprotocolized sites.

CONCLUSIONS

Implementation of enhanced recovery protocols for brain tumor surgery is feasible and effective, resulting in marked improvements in healthcare efficiency. Future studies, including implementation of the current protocol across the entire Providence system, are needed to maximize the potential benefits of enhanced recovery programs.

Lessons Learned in Elective Surgeries After 6 Pandemic Waves of SARS-CoV-2. A Single European Center Experience

BACKGROUND

The reported high surgical morbidity and mortality in patients with SARS-CoV-2 prompted preoperative screening and modification of surgical protocols. Although vaccination and treatment of COVID-19 have resulted in lower hospitalization rates and infection severity, publications on postoperative results have not been updated. The aim of the study was to analyze the outcomes of patients undergoing surgery in two periods with high incidence of SARS-CoV-2 infection, before and after vaccination.

MATERIALS AND METHODS

This is a prospective cohort study of patients undergoing surgery in two periods: March-June 2020 (Group2020) and December 2021-February 2022 (Group2022) (after massive vaccination).

RESULTS

In total, 618 patients who underwent surgery were included in the analysis (Group2020: 343 vs. Group2022: 275). Significantly more oncological procedures were performed in Group2020, and there were no differences in postoperative complications. Nosocomial SARS-CoV-2 infection occurred in 4 patients in Group2020 and 1 patient in Group2022. In Group 2022, 70 patients (25.4%) had COVID-19 prior to surgery, and 68 (97.1%) were vaccinated. Comparative analysis between patients with past COVID-19 and those without showed no difference in postoperative morbidity and mortality. According to the time elapsed between SARS-CoV-2 infection and surgery (≤ 7 or > 7 weeks), comparative analysis showed no significant differences.

CONCLUSION

The establishment of preoperative screening protocols for SARS-CoV-2 infection results in a low incidence of nosocomial infection and optimal postoperative outcomes. Preoperative SARS-CoV-2 infection in vaccinated patients was not associated with increased postoperative complications, even in shorter periods after infection. In surgical patients, individualized preoperative evaluation after SARS-CoV-2 infection may be more important than strict time limitation.

Is there an outcome benefit? Patient engagement technology in addition to the electronic medical record patient portal following elective colorectal surgery

BACKGROUND

Patient engagement technologies (PET) are an area of growing innovation and investment, but whether PET use in the setting of electronic medical record (EMR) supported patient portals are associated with improved outcomes is unknown. Therefore, we assessed PET and EMR activation among patients undergoing elective colorectal surgery on an enhanced recovery pathway.

METHODS

We identified adults undergoing elective colorectal surgery between 1/2017 and 7/2021. EMR activations were assessed and patients were considered PET users if they used a proprietary PET application. Multivariable logistic regression was used to identify factors associated with PET use and determine whether the level of engagement (percentage of messages read by the patient) was associated with 30-day outcomes.

RESULTS

484 patients (53.5% PET users, 81.6% with an activated EMR patient portal, 30.8% ≥ 70 years of age) were included. PET users were younger, more likely to have their EMR portal activated and had decreased odds of prolonged length of stay [odds ratio (OR) 0.5, 95% confidence interval (CI) 0.4-0.8]. Among patients ≥ 70 years, PET users had reduced odds of readmissions (OR 0.2, 95% CI 0.1-0.9) compared to PET non-users. The most engaged PET users had decreased morbidity (OR 0.2, 95% CI 0.1-0.8) and readmissions (OR 0.3, 95% CI 0.1-0.8) compared to the least engaged PET users.

CONCLUSION

When controlling for EMR activation, patients who use PET, specifically those with higher levels of engagement or aged ≥ 70, have improved outcomes following elective colorectal surgery. Interventions aimed at increasing the adoption of PET among older adults may be warranted.

Impact of frailty on the outcomes of patients undergoing degenerative spine surgery: a systematic review and meta-analysis

BACKGROUND

Degenerative spinal diseases are common in older adults with concurrent frailty. Preoperative frailty is a strong predictor of adverse clinical outcomes after surgery. This study aimed to investigate the association between health-related outcomes and frailty in patients undergoing spine surgery for degenerative spine diseases.

METHODS

A systematic review and meta-analysis were performed by electronically searching Ovid-MEDLINE, Ovid-Embase, Cochrane Library, and CINAHL for eligible studies until July 16, 2022. We reviewed all studies, excluding spinal tumours, non-surgical procedures, and experimental studies that examined the association between preoperative frailty and related outcomes after spine surgery. A total of 1,075 articles were identified in the initial search and were reviewed by two reviewers, independently. Data were subjected to qualitative and quantitative syntheses by meta-analytic methods.

RESULTS

Thirty-eight articles on 474,651 patients who underwent degenerative spine surgeries were included and 17 papers were quantitatively synthesized. The health-related outcomes were divided into clinical outcomes and patient-reported outcomes; clinical outcomes were further divided into postoperative complications and supportive management procedures. Compared to the non-frail group, the frail group was significantly associated with a greater risk of high mortality, major complications, acute renal failure, myocardial infarction, non-home discharge, reintubation, and longer length of hospital stay. Regarding patient-reported outcomes, changes in scores between the preoperative and postoperative Oswestry Disability Index scores were not associated with preoperative frailty.

CONCLUSIONS

In degenerative spinal diseases, frailty is a strong predictor of adverse clinical outcomes after spine surgery. The relationship between preoperative frailty and patient-reported outcomes is still inconclusive. Further research is needed to consolidate the evidence from patient-reported outcomes.

13 years of hand surgery without an anesthesiologist. An analysis of efficacy and safety of presurgical anesthesia as delivered by surgeons without the assistance of anesthesiologists

<b><br>Introduction:</b> The assistance of anaesthesiologist is considered an inseparable part of most surgical procedures, with the exception of a small proportion of minor procedures performed under local anaesthesia. In hand surgery, a vast majority of procedures, even those lasting several hours, can be carried out under regional (brachial plexus block) or local (infiltration) anaesthesia. These can be delivered by the surgeons themselves, allowing the surgeries to be carried out without the assistance of anesthesiologists.</br> <b><br>Aim:</b> The aim of this study was to analyze the efficacy and safety of presurgical anesthesia as delivered by surgeons without the assistance of anesthesiologists in the course of hand surgery procedures performed within the institution headed by the author of this article.</br> <b><br>Material and methods:</b> The analysis was based on the records of anesthesia protocols filled out by the surgeons who delivered the anesthesia and who operated on the patients. The variables considered included the efficacy of anesthesia and the anesthesia-related adverse effects and complications.</br> <b><br>Results:</b> Over a period of 13 years (2010-2022), a total of 24,703 surgeries were delivered; of these, 22,228 (91%) surgeries were carried out without anesthesiologists, with anesthesia being delivered by the surgeon him/herself. The efficacy of these procedures (local anasthesia and brachial plexus blocks combined) was 99%. A total of 631 (2.8%) anesthesia-related adverse reactions were recorded, most of them being transient, requiring immediate interventions and not leading to any serious sequelae. In only 17 cases (0.07%), adverse effects resulted in cancellation and rescheduling of the elective surgery.</br> <b><br>Conclusions:</b> Pre-surgical anesthesia as delivered prior to hand surgery procedures by the surgeons without the assistance of anesthesiologists is effective and safe while being associated with numerous benefits for patients, surgeons and the health care system's budget.</br>.

Machine learning to predict outcomes following endovascular abdominal aortic aneurysm repair

BACKGROUND

Endovascular aneurysm repair (EVAR) for abdominal aortic aneurysm (AAA) carries important perioperative risks; however, there are no widely used outcome prediction tools. The aim of this study was to apply machine learning (ML) to develop automated algorithms that predict 1-year mortality following EVAR.

METHODS

The Vascular Quality Initiative database was used to identify patients who underwent elective EVAR for infrarenal AAA between 2003 and 2023. Input features included 47 preoperative demographic/clinical variables. The primary outcome was 1-year all-cause mortality. Data were split into training (70 per cent) and test (30 per cent) sets. Using 10-fold cross-validation, 6 ML models were trained using preoperative features with logistic regression as the baseline comparator. The primary model evaluation metric was area under the receiver operating characteristic curve (AUROC). Model robustness was evaluated with calibration plot and Brier score.

RESULTS

Some 63 655 patients were included. One-year mortality occurred in 3122 (4.9 per cent) patients. The best performing prediction model for 1-year mortality was XGBoost, achieving an AUROC (95 per cent c.i.) of 0.96 (0.95-0.97). Comparatively, logistic regression had an AUROC (95 per cent c.i.) of 0.69 (0.68-0.71). The calibration plot showed good agreement between predicted and observed event probabilities with a Brier score of 0.04. The top 3 predictive features in the algorithm were 1) unfit for open AAA repair, 2) functional status, and 3) preoperative dialysis.

CONCLUSIONS

In this data set, machine learning was able to predict 1-year mortality following EVAR using preoperative data and outperformed standard logistic regression models.

Do we need a co-pilot in the operating theatre? A cross-sectional study on surgeons' perceptions

OBJECTIVE

The aim of this original study was to investigate general surgeons' perceptions on the role of dual surgeon operating for high-risk, elective complex surgical procedures.

MATERIAL AND METHODS

A 21-part cross-sectional online survey was self-completed by 85 general surgeons across hospitals in the UK. The survey assessed the perception of dual surgeon operating on patient morbidity and mortality, surgeons' burnout rates, complaints, patient waiting times and overall trainee experience. Statistical analysis was performed using R version 3.6.1.

RESULTS

Overall 78.8% believed that dual surgeon operating could help to overcome these human factors. Sub-analysis includes improve surgeon fatigue (89.4%), improve confidence (83.5%), improve decision-making (76.5%), minimise technical error (69.4%), improve communication, team work and leadership skills (65.9%). 65.9% believed it would reduce surgeons' burnout. There was a statistically significant relationship between the participants believing it would reduce surgeons' burnout and those who felt it would reduce complaints, Chi-squared(4) = [30.8], p = [0.00000342]. A statistically significant relationship was noted between participants believing it would reduce surgeons' burnout and those who felt it would reduce patient mortality/morbidity, Chi-squared(4) = [19.9], p = [0.000517].

CONCLUSION

The survey has highlighted positive surgeons' perceptions regarding dual surgeon operating.

Effect of dexamethasone administration for postoperative nausea and vomiting prophylaxis on glucose levels in adults with diabetes undergoing elective surgery: a systematic review with meta-analysis

OBJECTIVE

The objective of this review was to evaluate the effect of intravenous dexamethasone given intraoperatively for postoperative nausea and vomiting prophylaxis on maximal blood glucose level within the initial 24 hours following elective surgery for patients with diabetes.

INTRODUCTION

Postoperative nausea and vomiting is a prevalent adverse effect of anesthesia that leads to morbidity, increased health care costs, and unanticipated hospital admissions. Dexamethasone is an effective prophylactic agent that confers secondary analgesic and anti-inflammatory benefits. However, its use in patients with diabetes remains controversial due to the potential for increased postoperative blood glucose levels.

INCLUSION CRITERIA

This review considered studies with participants 18 years of age or older with type 1 or 2 diabetes undergoing an elective surgical procedure. Eligible studies reported postoperative blood glucose levels in adults with diabetes after receiving a single 4-10 mg prophylactic dose of intravenous dexamethasone intraoperatively for postoperative nausea and vomiting. The primary outcome was maximum blood glucose level in the first 24 hours after surgery. All study designs were eligible for inclusion. Studies were excluded if they lacked a control group with diabetes or if they did not report maximum blood glucose values in both groups.

METHODS

A search of MEDLINE, CINAHL Complete, Embase, Web of Science, TRIP database, and the Cochrane Database of Systematic Reviews was completed in October 2021. Gray literature resources were also searched. No date or language restrictions were applied. Methodological quality was assessed using JBI appraisal tools for randomized controlled trials, cohort studies, and case-control studies. A meta-analysis of maximal postoperative blood glucose level within 24 hours of surgery was performed, as well as subgroup analyses by dexamethasone dose, insulin treatment, and study design type.

RESULTS

Eleven studies (4 randomized controlled trials, 6 cohort studies, and 1 case-control study) were included in this review, with 1 study excluded from meta-analysis and results reported narratively. The total sample size of studies included in meta-analysis was 2567. The administration of dexamethasone significantly increased maximal blood glucose levels in the 24 hours immediately following surgery compared with control groups with diabetes, as demonstrated by randomized controlled trials (mean difference [MD] 39.56 mg/dL; 95% CI 16.18 to 62.94; P < 0.001; I2 = 87%) and observational studies (MD 26.31 mg/dL; 95% CI 7.10 to 45.52; P = 0.007; I2 = 92%). This increase in blood glucose was significant for all doses of dexamethasone: 4 mg (MD 40.81 mg/dL; 95% CI 2.42 to 79.19; P = 0.001; I2 = 91%), 8 mg (randomized controlled trials only; MD 39.45 mg/dL; 95% CI 15.32 to 63.58; P = 0.001; I2 = 86%), and mixed 4-10 mg dose (MD 30.82 mg/dL; 95% CI 6.75 to 54.88; P < 0.012; I2 = 93%). Postoperative hyperglycemia persisted in studies using insulin treatment as well as those not using insulin protocols. The overall certainty of the findings ranged from very low for outcomes that included cohort studies to moderate when outcomes from randomized controlled trials were analyzed separately. However, the quantitative findings of the experimental and observational studies were clinically similar. Risk of bias presented minimal concerns in all included studies.

CONCLUSIONS

Dexamethasone leads to transient postoperative hyperglycemia in patients with diabetes undergoing elective surgery when given as a single 4-10 mg intravenous dose for postoperative nausea and vomiting prophylaxis. The clinical relevance of hyperglycemia is debatable given its small magnitude and transient nature. Without more tightly controlled data, methodological consistency, and baseline blood glucose values, it is impossible to test causal links between hyperglycemia and pre-existing patient factors (eg, hemoglobin A1C levels) or postoperative complications.

REVIEW REGISTRATION

PROSPERO CRD42020185607.