Associated factors of mortality and morbidity in emergency and elective abdominal surgery: a two-year prospective cohort study at lacor hospital, Uganda.

BACKGROUND: The mortality rate associated with open abdominal surgery is a significant concern for patients and healthcare providers. This is particularly worrisome in Africa due to scarce workforce resources and poor early warning systems for detecting physiological deterioration in patients who develop complications. METHODS: This prospective cohort study aimed to follow patients who underwent emergency or elective abdominal surgery at Lacor Hospital in Uganda. The participants were patients who underwent abdominal surgery at the hospital between April 27th, 2019 and July 07th, 2021. Trained research staff collected data using standardized forms, which included demographic information (age, gender, telephone contact, and location), surgical indications, surgical procedures, preoperative health status, postoperative morbidity and mortality, and length of hospital stay. RESULTS: The present study involved 124 patients, mostly male, with an average age of 35 years, who presented with abdominal pain and varying underlying comorbidities. Elective cases constituted 60.2% of the total. The common reasons for emergency and elective surgery were gastroduodenal perforation and cholelithiasis respectively. The complication rate was 17.7%, with surgical site infections being the most frequent. The mortality rate was 7.3%, and several factors such as preoperative hypotension, deranged renal function, postoperative use of vasopressors, and postoperative assisted ventilation were associated with it. Elective and emergency-operated patients showed no significant difference in survival (P-value = 0.41) or length of hospital stay (P-value = 0.17). However, there was a significant difference in morbidity (p < 0.001). CONCLUSION: Cholelithiasis and gastroduodenal perforation were key surgical indications, with factors like postoperative ventilation and adrenaline infusion linked to mortality. Emergency surgeries had higher complication rates, particularly surgical site infections, despite similar hospital stay and mortality rates compared to elective surgeries.

The association of postoperative morbidity and age on 5-year survival after colorectal surgery in the elderly population: a nationwide cohort study.

AIM: This study aimed to evaluate the association of age and postoperative morbidity on 5-year overall survival (OS) after elective surgery for colorectal cancer. METHOD: Patients undergoing elective, curatively intended surgery for colorectal cancer Union for International Cancer Control Stages I-III between January 2014 and December 2019 were selected from four Danish nationwide healthcare databases. Patients were divided into four groups: group I 65-69 years old; group II 70-74 years old; group III 75-79 years old; and group IV ≥80 years old. Propensity score matching was used to reduce potential confounding bias. The primary outcome was the association of age and postoperative morbidity with 5-year OS. The secondary outcome was conditional survival, given that the patient had already survived the first 90 days after surgery. RESULTS: After propensity score matching with a 1:1 ratio, group II contained 2221 patients; group III 952 patients; and group IV 320 patients. There was no significant difference in 5-year OS between group I (reference) and groups II and III (P = 0.4 and P = 0.9, respectively). Patients with severe postoperative complications within 30 days after surgery had a significantly decreased OS (P < 0.01); however, when patients who died within the first 90 days were excluded from the analysis, the differences in 5-year OS were less pronounced across all age groups. CONCLUSION: Postoperative morbidity, and not patient age, was associated with a lower 5-year OS. Long-term survival for patients who experience a complication is similar to patients who did not have a complication when conditioning on 90 days of survival.

Patients' characteristics and 30-day mortality for those undergoing elective surgeries during the COVID-19 pandemic in Bangladesh.

BACKGROUND: The COVID-19 pandemic has significantly impacted the surgical practice throughout the world, including elective surgical care. This study investigated the characteristics of patients undergoing elective surgery, the prevalence of COVID-19 infection, the surgical procedures performed, and 30-day mortality in general and pediatric surgical settings in selected tertiary-level hospitals in Bangladesh from November 2020 to August 2021. METHODS: This serial cross-sectional study included 264 patients scheduled for elective surgeries during the study period. All patients underwent COVID-19 real-time polymerase chain reaction (RT-PCR) testing within 24 hours before surgery. Data on age, sex, common comorbidities, surgical procedures, and 30-day mortality were collected and analyzed. Furthermore, comparisons were made between COVID-19 positive and negative patients. RESULTS: The prevalence of COVID-19 infection among patients was 10.6%. Older age, a history of major surgery within the last three months, hypertension, and diabetes mellitus were significantly associated with COVID-19 infection. All COVID-19-negative patients underwent surgery, while only 46.4% of COVID-19-positive patients underwent surgery. The most common surgical procedures were related to the digestive system, breast, and urinary system. Only one patient (0.4%) died within 30 days after surgery among the COVID-19-negative patients, whereas two patients (7.1%) died among the COVID-19-positive patients: one before surgery and one after surgery. CONCLUSIONS: This study provides valuable insights into the characteristics, burden of COVID-19 infection, and 30-day mortality of patients undergoing elective surgery in tertiary care centers in Bangladesh during the pandemic.

Effect of hemodialysis on short-term outcomes after colon cancer surgery.

BACKGROUND: Hemodialysis patients who undergo surgery have a high risk of postoperative complications. The aim of this study was to determine whether colon cancer surgery can be safely performed in hemodialysis patients. METHODS: This multicenter retrospective study included 1372 patients who underwent elective curative resection surgery for colon cancer between April 2016 and March 2020. RESULTS: Of the total patients, 19 (1.4%) underwent hemodialysis, of whom 19 (100%) had poor performance status and 18 had comorbidities (94.7%). Minimally invasive surgery was performed in 78.9% of hemodialysis patients. The postoperative complication rate was significantly higher in hemodialysis than non-hemodialysis patients (36.8% vs. 15.5%, p = 0.009). All postoperative complications in the hemodialysis patients were infectious type. Multivariate analysis revealed a significant association of hemodialysis with complications (odds ratio, 2.9362; 95%CI, 1.1384-7.5730; p = 0.026). CONCLUSION: Despite recent advances in perioperative management and minimally invasive surgery, it is necessary to be aware that short-term complications can still occur, especially infectious complications in hemodialysis patients.

Postoperative Mortality in Patients With Cirrhosis: Reconsidering Expectations.

BACKGROUND: A diagnosis of cirrhosis increases a patient's risk of postoperative mortality. Surgeons are reticent to operate when cirrhosis is known unless no option is available. This study aimed to identify the modern perioperative risk in cirrhotic patients undergoing intervention under general anesthesia for non-transplant operations. METHODS: A retrospective chart review was conducted utilizing the Rush Medical Center electronic medical record. All patients over 18 years of age with a diagnosis of cirrhosis undergoing intervention between 2009 and 2019 were reviewed. 90-day mortality rates in patients grouped by Child's score, Model for End-Stage Liver Disease (MELD), and Model for End-Stage Liver Disease with sodium incorporated (MELDNa) were compared to previously accepted rates. RESULTS: 93 patients (46% women) aged 22-72 years of all Child-Turcot-Pugh (CTP) (40% A, 36% B, and 25% C) classifications and MELD/MELDNa ranging 6-40 were analyzed. 90-day mortality of the entire population was 16%, significantly lower than expected based on CTP score (16% vs. 32%; P = .0005), MELD (16% vs. 41%; P < .0001), and MELDNa (16% vs. 46.8%; P < .0001). This was also true for CTP-B patients (12% vs. 30%; P = .025), CTP-C patients (35% vs. 70%; P = .0002), patients with MELD >14 (27% vs. 70%; P < .001), and patients with MELDNa >14 (23% vs. 70%; P < .0001). CONCLUSION: Data indicate that perioperative mortality is lower than widely accepted. This suggests the need for a national database study using a representative population to determine the risk of mortality for patients with cirrhosis having surgery in recent times. Accurate estimation of this risk allows for meaningful discussion between physicians and patients when deciding to proceed with elective, necessary operations.

Reliability of hospital-level mortality in abdominal aortic aneurysm repair.

OBJECTIVE: The relationship between volume and surgical outcomes has been shown for a variety of surgical procedures. The effects in abdominal aortic aneurysm repair have continued to be debated. Reliability adjustment has been used as a method to remove statistical noise from hospital-level outcomes. However, its impact on aortic aneurysm repair is not well understood. METHODS: We used prospectively collected data from the Vascular Quality Initiative to identify all patients who had undergone abdominal aortic aneurysm repair from 2003 to 2019. We first calculated the hospital-level risk-adjusted 30-day mortality rates. We subsequently used hierarchical logistic regression modeling to adjust for measurement reliability using empirical Bayes techniques. The effect of volume on risk- and reliability-adjusted mortality rates was then assessed using linear regression. RESULTS: Between 2003 and 2019, 67,073 abdominal aortic aneurysms were repaired, of which 11,601 (17.3%) were repaired with an open approach. The median annual volume was 7.4 (interquartile range, 3.0-13.3) for open repairs and 35.4 (interquartile range, 18.8-59.8) for endovascular repairs. Of the 223 hospitals that had performed open repairs during the study period, only 11 (4.9%) had performed ≥15 open repairs annually, and the risk-adjusted mortality rates varied from 0% to 75% across all centers. After reliability adjustment, the variability of the risk-adjusted mortality rates had decreased significantly to 1.3% to 8.2%. The endovascular repair risk-adjusted mortality rate variability had decreased from 0% to 14.3% to 0.3% to 2.8% after reliability adjustment. A decreasing trend in mortality was found with increasing an annual case volume for open repair with each additional annual case associated with a 0.012% decrease in mortality (P = .05); however, the relationship was not significant for endovascular repair (P = .793). CONCLUSIONS: We found that most hospitals do not perform a sufficient number of annual cases to generate a reliable center-specific mortality rate for open aneurysm repair. Center-specific mortality rates for low-volume centers should be viewed with caution, because a substantial proportion of the variation for these outcomes will be statistical noise rather than true center-level differences in the quality of care.

Death after surgery among patients with chronic disease: prospective study of routinely collected data in the English NHS.

BACKGROUND: Five million surgeries take place in the NHS each year. Little is known about the prevalence of chronic diseases among these patients, and the association with postoperative outcomes. METHODS: Analysis of routine data from all NHS hospitals in England including patients aged ≥18 yr undergoing non-obstetric surgery between January 1, 2010 and December 31, 2015. The primary outcome was death within 90 days after surgery. For each chronic disease, we adjusted for age, sex, presence of other diseases, emergency surgery, and year using logistic regression models. We defined high-risk diseases as those with an adjusted odds ratio (OR) for death ≥2 and report associated 2-yr survival. RESULTS: We included 8 624 611 patients (median age, 53 [36-68] yr), of whom 6 913 451 (80.2%) underwent elective surgery and 1 711 160 (19.8%) emergency surgery. Overall, 2 311 600 (26.8%) patients had a chronic disease, of whom 109 686 (4.7%) died within 90 days compared with 24 136 (0.4%) of 6 313 011 without chronic disease. Respiratory disease (1 002 281 [11.6%]), diabetes mellitus (662 706 [7.7%]), and cancer (310 363; 3.6%) were the most common. Four chronic diseases accounted for 7.7% of patients but 59.0% of deaths: cancer (37 693 deaths [12.1%]; OR=8.3 [8.2-8.5]), liver disease (8638 deaths [10.3%]; OR=4.5 [4.4-4.7]), cardiac failure (26 604 deaths [12.6%]; OR=2.4 [2.4-2.5]), and dementia (19 912 deaths [17.9%]; OR=2.0 [1.9-2.0]). Two-year survival was 67.7% among patients with high-risk chronic disease, compared with 97.1% without. CONCLUSION: One in four surgical patients has a chronic disease with an associated 10-fold increase in risk of postoperative death. Two-thirds of all deaths after surgery occur among patients with high-risk diseases (cancer, cardiac failure, liver disease, dementia).

Elective neck dissection improves the survival of patients with T2N0M0 oral squamous cell carcinoma: a study of the SEER database.

BACKGROUND: Treatment of clinical N0 neck tumours is controversial in early-stage oral squamous cell carcinoma (OSCC), possibly because T1N0M0 and T2N0M0 merge together at early stages. The purposes of this study were to compare survival outcomes only for T2N0M0 cases based upon treatment elective neck dissection versus neck observation. METHODS: T2N0M0 OSCC cases were identified in the Surveillance, Epidemiology, and End Results database of the United States National Cancer Institute between 2004 and 2015. Survival curves for different variable values were generated using Kaplan-Meier estimates and compared using the log-rank test. Variables that achieved significance at P < 0.05 were entered into multivariable analyses via the Cox proportional hazards multivariate regression. RESULTS: A total of 2857 patients were selected, and 2313 cases were available for disease specific survival (DSS). The 5-year and 10-year overall survival (OS) were 66.7 and 46% for patients receiving elective neck dissection (END), respectively, and 56.4 and 37.2% for patients with neck observation (P < 0.0001). The 5-year and 10-year DSS were 73.6 and 64% for the END group, respectively, versus 64.5 and 54.5% for the neck observation group (P < 0.0001). More importantly, performing END was independently associated with favourable DSS and OS for patients with T2N0M0 OSCC [hazard ratio (HR) = 0.769, P = 0.0069 for DSS; HR = 0.829, P = 0.0031 for OS, neck observation group as reference] according to multivariate survival analysis. CONCLUSION: END is recommended for T2N0M0 OSCC cases and it is associated with improved DSS and OS.

Differences in mortality and complication rates following revision knee arthroplasty performed for urgent versus elective indications.

AIMS: To compare rates of serious adverse events in patients undergoing revision knee arthroplasty with consideration of the indication for revision (urgent versus elective indications), and compare these with primary arthroplasty and re-revision arthroplasty. METHODS: Patients undergoing primary knee arthroplasty were identified in the national Hospital Episode Statistics (HES) between 1 April 1997 to 31 March 2017. Subsequent revision and re-revision arthroplasty procedures in the same patients and same knee were identified. The primary outcome was 90-day mortality and a logistic regression model was used to investigate factors associated with 90-day mortality and secondary adverse outcomes, including infection (undergoing surgery), pulmonary embolism, myocardial infarction, and stroke. Urgent indications for revision arthroplasty were defined as infection or fracture, and all other indications (e.g. loosening, instability, wear) were included in the elective indications cohort. RESULTS: A total of 939,021 primary knee arthroplasty procedures were included (939,021 patients), of which 40,854 underwent subsequent revision arthroplasty, and 9,100 underwent re-revision arthroplasty. Revision surgery for elective indications was associated with a 90-day rate of mortality of 0.44% (135/30,826; 95% confidence interval (CI) 0.37 to 0.52) which was comparable to primary knee arthroplasty (0.46%; 4,292/939,021; 95% CI 0.44 to 0.47). Revision arthroplasty for infection was associated with a much higher mortality of 2.04% (184/9037; 95% CI 1.75 to 2.35; odds ratio (OR) 3.54; 95% CI 2.81 to 4.46), as was revision for periprosthetic fracture at 5.25% (52/991; 95% CI 3.94 to 6.82; OR 6.23; 95% CI 4.39 to 8.85). Higher rates of pulmonary embolism, myocardial infarction, and stroke were also observed in the infection and fracture cohort. CONCLUSION: Patients undergoing revision arthroplasty for urgent indications (infection or fracture) are at higher risk of mortality and serious adverse events in comparison to primary knee arthroplasty and revision arthroplasty for elective indications. These findings will be important for patient consent and shared decision-making and should inform service design for this patient cohort. Cite this article: Bone Joint J 2021;103-B(10):1578-1585.

A comparison of comorbidity measures for predicting mortality after elective hip and knee replacement: A cohort study of data from the National Joint Registry in England and Wales.

BACKGROUND: The risk of mortality following elective total hip (THR) and knee replacements (KR) may be influenced by patients' pre-existing comorbidities. There are a variety of scores derived from individual comorbidities that can be used in an attempt to quantify this. The aims of this study were to a) identify which comorbidity score best predicts risk of mortality within 90 days or b) determine which comorbidity score best predicts risk of mortality at other relevant timepoints (30, 45, 120 and 365 days). PATIENTS AND METHODS: We linked data from the National Joint Registry (NJR) on primary elective hip and knee replacements performed between 2011-2015 with pre-existing conditions recorded in the Hospital Episodes Statistics. We derived comorbidity scores (Charlson Comorbidity Index-CCI, Elixhauser, Hospital Frailty Risk Score-HFRS). We used binary logistic regression models of all-cause mortality within 90-days and within 30, 45, 120 and 365-days of the primary operation using, adjusted for age and gender. We compared the performance of these models in predicting all-cause mortality using the area under the Receiver-operator characteristics curve (AUROC) and the Index of Prediction Accuracy (IPA). RESULTS: We included 276,594 elective primary THRs and 338,287 elective primary KRs for any indication. Mortality within 90-days was 0.34% (N = 939) after THR and 0.26% (N = 865) after KR. The AUROC for the CCI and Elixhauser scores in models of mortality ranged from 0.78-0.81 after THR and KR, which slightly outperformed models with ASA grade (AUROC = 0.77-0.78). HFRS performed similarly to ASA grade (AUROC = 0.76-0.78). The inclusion of comorbidities prior to the primary operation offers no improvement beyond models with comorbidities at the time of the primary. The discriminative ability of all prediction models was best for mortality within 30 days and worst for mortality within 365 days. CONCLUSIONS: Comorbidity scores add little improvement beyond simpler models with age, gender and ASA grade for predicting mortality within one year after elective hip or knee replacement. The additional patient-specific information required to construct comorbidity scores must be balanced against their prediction gain when considering their utility.

Short term outcomes associated with patients requiring blood transfusion following elective laminectomy and fusion for lumbar stenosis: A propensity-matched analysis.

Perioperative blood transfusion has been associated with poor outcomes but the impacts of transfusion after fusion for lumbar stenosis have not been well-described. We assessed this effect in a large cohort of patients from 2012 to 2018 in the National Surgical Quality Improvement Program (NSQIP). We evaluated baseline characteristics including demographics, comorbidities, hematocrit, and operative characteristics. We generated propensity scores using baseline characteristics and patients were matched to approximate randomization. We assessed odds of 30-day outcomes including prolonged length-of-stay (LOS), complications, discharge to facility, readmission, reoperation, and death using logistic regression. We identified 16,329 eligible patients who underwent lumbar fusion for stenosis; 1,926 (11.8%) received a transfusion. Before matching, there were multiple differences in baseline covariates including age, gender, BMI, ASA class, medical comorbidities, hematocrit, coagulation indices, platelets, operative time, fusion technique, number of levels fused, and osteotomy. However, after matching, no significant differences remained. In the matched cohorts, transfusion was associated with increased prolonged LOS (OR 1.66, 95% CI 1.45-1.91, p < 0.001), minor complication (OR 1.60, 95% CI 1.20-2.12, p = 0.001), major complication (OR 1.51, 95% CI 1.16-1.98, p = 0.003), any complication (OR 1.54, 95% CI 1.24-1.92, p < 0.001), discharge to facility (OR 1.70, 95% CI 1.48-1.95, p < 0.001), 30-day readmission (OR 1.56, 95% CI 1.23-1.99, p < 0.001), and 30-day reoperation (OR 1.85, 95% CI 1.35-2.53, p < 0.001). Although transfusion is performed based on perceived clinical need, this study contributes to growing evidence that it is important to balance the risks of perioperative blood transfusion with its benefits.

Patient Selection for Routine Troponin Monitoring After Noncardiac Surgery.

Background Myocardial infarction is an important complication after noncardiac surgery. Therefore, perioperative troponin surveillance is recommended for patients at risk. The aim of this study was to identify patients at high risk of perioperative myocardial infarction (POMI), in order to aid appropriate selection and to omit redundant laboratory measurements in patients at low risk. Methods and Results This observational cohort study included patients ≥60 years of age who underwent intermediate to high risk noncardiac surgery. Routine postoperative troponin I monitoring was performed. The primary outcome was POMI. Classification and regression tree analysis was used to identify patient groups with varying risks of POMI. In each subgroup, the number needed to screen to identify 1 patient with POMI was calculated. POMI occurred in 216 (4%) patients and other myocardial injury in 842 (15%) of the 5590 included patients. Classification and regression tree analysis divided patients into 14 subgroups in which the risk of POMI ranged from 1.7% to 42%. Using a risk of POMI ≥2% to select patients for routine troponin I monitoring, this monitoring would be advocated in patients ≥60 years of age undergoing emergency surgery, or those undergoing elective surgery with a Revised Cardiac Risk Index class >2 (ie >1 risk factor). The number needed to screen to detect a patient with POMI would be 14 (95% CI 14-14) and 26% of patients with POMI would be missed. Conclusions To improve selection of high-risk patients ≥60 years of age, routine postoperative troponin I monitoring could be considered in patients undergoing emergency surgery, or in patients undergoing elective surgery classified as having a revised cardiac risk index class >2.

The Impact of the Coronavirus Disease 2019 Pandemic on Neurosurgical Practice and Feasibility of Safe Resumption of Elective Procedures During this Era in a Large Referral Center in Tehran, Iran: An Unmatched Case-Control Study.

OBJECTIVE: The coronavirus disease 2019 (COVID-19) pandemic has considerably affected surgical practice. The present study aimed to investigate the effects of the pandemic on neurosurgical practice and the safety of the resumption of elective procedures through implementing screening protocols in a high-volume academic public center in Iran, as one of the countries severely affected by the pandemic. METHODS: This unmatched case-control study compared 2 populations of patients who underwent neurosurgical procedures between June 1, 2019 and September 1, 2019 and the same period in 2020. In the prospective part of the study, patients who underwent elective procedures were tested for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection postoperatively to evaluate the viability of our screening protocol. RESULTS: Elective and emergency procedures showed significant reduction during the pandemic (59.4%, n = 168 vs. 71.3%, n = 380) and increase (28.7%, n = 153 vs. 40.6%, n = 115, respectively; P = 0.003). The proportional distribution of neurosurgical categories remained unchanged during the pandemic. Poisson regression showed that the reduction in total daily admissions and some categories, including spine, trauma, oncology, and infection were significantly correlated with the pandemic. Among patients who underwent elective procedures, 0 (0.0%) and 26 (16.25%) had positive test results on days 30 and 60 postoperatively, respectively. Overall mortality was comparable between the pre-COVID-19 and COVID-19 periods, yet patients with concurrent SARS-CoV-2 infection showed substantially higher mortality (65%). CONCLUSIONS: By implementing safety and screening protocols with proper resource allocation, the emergency care capacity can be maintained and the risk minimized of hospital-acquired SARS-CoV-2 infection, complications, and mortality among neurosurgical patients during the pandemic. Similarly, for elective procedures, according to available resources, hospital beds can be allocated for patients with a higher risk of delayed hospitalization and those who are concerned about the risk of hospital-acquired infection can be reassured.

Preoperative and Intraoperative Blood Pressure Variability Independently Correlate with Outcomes.

BACKGROUND: Blood pressure variability (BPV) describes visit-to-visit blood pressure (BP) changes independent of hypertension. Preoperative BPV and intraoperative BPV are associated with increased postoperative outcomes. We investigated the impact of both preoperative BPV and intraoperative BPV on elective surgical outcomes, specifically whether preoperative BPV and intraoperative BPV were independent risk factors for surgical complications. MATERIALS AND METHODS: We investigated 600 patients undergoing elective surgery lasting more than two h and who had ≥8 outpatient BP recordings over three preoperative years. Age, sex, ethnicity, BMI, current medical problems, and medications at time of surgery were recorded. BPV was calculated as the standard deviation (SD) of systolic or diastolic BP for the 369 valid patients. Average BPV were compared between adverse outcomes of readmission, wound infection, acute kidney injury, death, myocardial infarction, and cerebral vascular accident. RESULTS: Three-hundred-sixty-nine (52.6% male, 47.4% female, 98.1% non-Hispanic) patients (mean age 62.5) were included in the study. Preoperative systolic (P = 0.043) and diastolic (P = 0.009) BPV were higher for patients with the combined endpoint of all adverse events. Preoperative systolic BPV was correlated with intraoperative BPV (P = 0.010). Both systolic and diastolic preoperative BPV was found to be independent from intraoperative BPV. Otolaryngology procedures were associated with less adverse outcomes (P = 0.034), whil antimicrobials (P = 0.022), autonomic drugs (P < 0.001), or respiratory drugs (P = 0.032) was associated with an increased likelihood of adverse outcome. CONCLUSION: Preoperative DBPV is associated with increased risk of readmission, wound infection and the combined endpoint of all adverse events. Intraoperative systolic blood pressure variability (SPBV) is associated with increased risk of acute kidney injury and the combined endpoint of all adverse events. Preoperative DBPV and intraoperative SBPV are independent risk factors for ninety-d postoperative outcomes. BPV should be considered in individualized risk assessment when assessing patient eligibility for elective procedures.

Retroperitoneal versus transperitoneal approach for elective open abdominal aortic aneurysm repair.

BACKGROUND: There has been extensive debate in the surgical literature regarding the optimum surgical access approach to the infrarenal abdominal aorta during an operation to repair an abdominal aortic aneurysm. The published trials comparing retroperitoneal (RP) and transperitoneal (TP) aortic surgery show conflicting results. This is an update of the review first published in 2016. OBJECTIVES: To assess the effectiveness and safety of the retroperitoneal versus transperitoneal approach for elective open abdominal aortic aneurysm repair on mortality, complications, hospital stay and blood loss. SEARCH METHODS: The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase and CINAHL databases and the World Health Organization International Clinical Trials Registry Platform and the ClinicalTrials.gov trials registers to 30 November 2020. The review authors searched the Chinese Biomedical Literature Database and handsearched reference lists of relevant articles to identify additional trials. SELECTION CRITERIA: We included randomized controlled trials (RCTs) that assessed the RP approach versus the TP approach for elective open abdominal aortic aneurysm (AAA) repair. There were no restrictions on language or publication status. DATA COLLECTION AND ANALYSIS: Two review authors independently extracted data from the included trials. We resolved any disagreements through discussion with a third review author. Two review authors independently assessed the risk of bias in included trials with the Cochrane risk of bias tool. For dichotomous outcomes, we calculated the odds ratio (OR) with the corresponding 95% confidence interval (CI). For continuous data, we calculated a pooled estimate of treatment effect by calculating the mean difference (MD) and standard deviation (SD) with corresponding 95% CIs. We pooled data using a fixed-effect model, unless we identified heterogeneity, in which case we used a random-effects model. We used GRADE to assess the overall certainty of the evidence. We evaluated the outcomes of mortality, complications, intensive care unit (ICU) stay, hospital stay, blood loss, aortic cross-clamp time and operating time. MAIN RESULTS: We identified no new studies from the updated searches. After reassessment, we included one study which had previously been excluded. Five RCTs with a combined total of 152 participants are included. The overall certainty of the evidence ranged from low to very low because of the low methodological quality of the included trials (unclear random sequence generation method and allocation concealment, and no blinding of outcome assessors), small sample sizes, small number of events, high heterogeneity and inconsistency between the included trials, no power calculations and relatively short follow-up. There was no evidence of a difference between the RP approach and the TP approach regarding mortality (odds ratio (OR) 0.32, 95% CI 0.01 to 8.25; 3 studies, 110 participants; very low-certainty evidence). Similarly, there was no evidence of a difference in complications such as hematoma (OR 0.90, 95% CI 0.13 to 6.48; 2 studies, 75 participants; very low-certainty evidence), abdominal wall hernia (OR 10.76, 95% CI 0.55 to 211.78; 1 study, 48 participants; very low-certainty evidence), or chronic wound pain (OR 2.20, 95% CI 0.36 to 13.34; 1 study, 48 participants; very low-certainty evidence) between the RP and TP approaches in participants undergoing elective open AAA repair. The RP approach may reduce ICU stay (mean difference (MD) -19.02 hours, 95% CI -30.83 to -7.21; 3 studies, 106 participants; low-certainty evidence); hospital stay (MD -3.30 days, 95% CI -4.85 to-1.75; 5 studies, 152 participants; low-certainty evidence); and blood loss (MD -504.87 mL, 95% CI -779.19 to -230.56; 4 studies, 129 participants; very low-certainty evidence). There was no evidence of a difference between the RP approach and the TP approach regarding aortic cross-clamp time (MD 0.69 min, 95% CI -7.23 to 8.60; 4 studies, 129 participants; very low-certainty evidence) or operating time (MD -15.94 min, 95% CI -34.76 to 2.88; 4 studies, 129 participants; very low-certainty evidence). AUTHORS' CONCLUSIONS: Very low-certainty evidence from five small RCTs showed no clear evidence of a difference between the RP approach and the TP approach for elective open AAA repair in terms of mortality, or for rates of complications including hematoma (very low-certainty evidence), abdominal wall hernia (very low-certainty evidence), or chronic wound pain (very low-certainty evidence). However, a shorter intensive care unit (ICU) stay and shorter hospital stay was probably indicated following the RP approach compared to the TP approach (both low-certainty evidence). A possible reduction in blood loss was also shown after the RP approach (very low-certainty evidence). There is no clear difference between the RP approach and TP approach in aortic cross-clamp time or operating time. Further well-designed, large-scale RCTs assessing the RP approach versus TP approach for elective open AAA repair are required.