African Surgical Outcomes Study Research Articles

1096 The African Surgical Outcomes Study in Paediatric Patients (ASOS-Paeds) and Global Paediatric Perioperative Mortality - a Meta-analysis

Abstract Aim There is little data for surgical outcomes of children in Africa. This is of particular importance as children constitute 40% of the African population, compared to a global average of 25%. As part of ASOS-Paeds - a prospective cohort study of children undergoing surgery in African countries, we undertook a meta-analysis to synthesise the evidence on global paediatric perioperative mortality. Method We searched MEDLINE, Embase and WHO Global Index Medicus for studies published within the last decade, reporting paediatric perioperative mortality. We included studies with ≥200 children that reported perioperative mortality for multiple surgical specialties and procedures. Perioperative mortality was defined as death within 30 days of surgery. For meta-analysis, proportions were combined using a random effects model. Results After screening 13,258 s and reviewing 158 full-text reports, data from 9 studies were eligible for synthesis along with data from ASOS-Paeds. The meta-analysis included 579,733 children from Africa, Europe, and North America. The pooled perioperative mortality rate per 1,000 children (95% CI) was 17.91 (9.78, 26.04) in Africa compared to 2.18 (0.95, 3.42) in Europe and North America. This equates to excess paediatric perioperative mortality in Africa between 6 (in the best-case scenario) to 25 (in the worst-case scenario) per 1,000 children. Conclusions Perioperative mortality for children undergoing surgery in Africa is 8-fold higher than in Europe and North America. Access to safe and affordable anaesthesia and surgery should be a public health priority and urgent action is needed to improve surgical outcomes for children in Africa.

Method of Anesthesia and Perioperative Risk Factors, Maternal Anesthesia Complications, and Neonatal Mortality Following Cesarean Delivery in Africa: A Substudy of a 7-Day Prospective Observational Cohort Study.

The African Surgical Outcomes Study (ASOS) found that maternal mortality following cesarean delivery in Africa is 50 times higher than in high-income countries, and associated with obstetric hemorrhage and anesthesia complications. Mothers who died were more likely to receive general anesthesia (GA). The associations between GA versus spinal anesthesia (SA) and preoperative risk factors, maternal anesthesia complications, and neonatal outcomes following cesarean delivery in Africa are unknown. This is a secondary explanatory analysis of 3792 patients undergoing cesarean delivery in ASOS, a prospective observational cohort study, across 22 African countries. The primary aim was to estimate the association between preoperative risk factors and the outcome of the method of anesthesia delivered. Secondary aims were to estimate the association between the method of anesthesia and the outcomes (1) maternal intraoperative hypotension, (2) severe maternal anesthesia complications, and (3) neonatal mortality. Generalized linear mixed models adjusting for obstetric gravidity and gestation, American Society of Anesthesiologists (ASA) category, urgency of surgery, maternal comorbidities, fetal distress, and level of anesthesia provider were used. Of 3709 patients, SA was performed in 2968 (80%) and GA in 741 (20%). Preoperative factors independently associated with GA for cesarean delivery were gestational age (adjusted odds ratio [aOR], 1.093; 95% confidence interval [CI], 1.052-1.135), ASA categories III (aOR, 11.84; 95% CI, 2.93-46.31) and IV (aOR, 11.48; 95% CI, 2.93-44.93), eclampsia (aOR, 3.92; 95% CI, 2.18-7.06), placental abruption (aOR, 6.23; 95% CI, 3.36-11.54), and ruptured uterus (aOR, 3.61; 95% CI, 1.36-9.63). SA was administered to 48 of 94 (51.1%) patients with eclampsia, 12 of 28 (42.9%) with cardiac disease, 14 of 19 (73.7%) with preoperative sepsis, 48 of 76 (63.2%) with antepartum hemorrhage, 30 of 55 (54.5%) with placenta previa, 33 of 78 (42.3%) with placental abruption, and 12 of 29 (41.4%) with a ruptured uterus. The composite maternal outcome "all anesthesia complications" was more frequent in GA than SA (9/741 [1.2%] vs 3/2968 [0.1%], P < .001). The unadjusted neonatal mortality was higher with GA than SA (65/662 [9.8%] vs 73/2669 [2.7%], P < .001). The adjusted analyses demonstrated no association between method of anesthesia and (1) intraoperative maternal hypotension and (2) neonatal mortality. Analysis of patients undergoing anesthesia for cesarean delivery in Africa indicated patients more likely to receive GA. Anesthesia complications and neonatal mortality were more frequent following GA. SA was often administered to high-risk patients, including those with eclampsia or obstetric hemorrhage. Training in the principles of selection of method of anesthesia, and the skills of safe GA and neonatal resuscitation, is recommended.

Postoperative outcomes associated with surgical care for women in Africa: an international risk-adjusted analysis of prospective observational cohorts.

Improving women's health is a critical component of the sustainable development goals. Although obstetric outcomes in Africa have received significant focus, non-obstetric surgical outcomes for women in Africa remain under-examined. We did a secondary analysis of the African Surgical Outcomes Study (ASOS) and International Surgical Outcomes Study (ISOS), two 7-day prospective observational cohort studies of outcomes after adult inpatient surgery. This sub-study focuses specifically on the analysis of the female, elective, non-obstetric, non-gynaecological surgical data collected during these two large multicentre studies. The African data from both cohorts are compared with international (non-African) outcomes in a risk-adjusted logistic regression analysis using a generalised linear mixed-effects model. The primary outcome was severe postoperative complications including in-hospital mortality in Africa compared with non-African outcomes. A total of 1698 African participants and 18 449 international participants met the inclusion criteria. The African cohort were younger than the international cohort with a lower preoperative risk profile. Severe complications occurred in 48 (2.9%) of 1671, and 431 (2.3%) of 18 449 patients in the African and international cohorts, respectively, with in-hospital mortality after severe complications of 23/48 (47.9%) in Africa and 78/431 (18.1%) internationally. Women in Africa had an adjusted odds ratio of 2.06 (95% confidence interval, 1.17-3.62; P=0.012) of developing a severe postoperative complication after elective non-obstetric, non-gynaecological surgery, compared with the international cohort. Women in Africa have double the risk adjusted odds of severe postoperative complications (including in-hospital mortality) after elective non-obstetric, non-gynaecological surgery compared with the international incidence.

Postoperative Outcomes Associated With Procedural Sedation Conducted by Physician and Nonphysician Anesthesia Providers: Findings From the Prospective, Observational African Surgical Outcomes Study.

There is an unmet need for essential surgical services in Africa. Limited anesthesia services are a contributing factor. Nonphysician anesthesia providers are utilized to assist with providing anesthesia and procedural sedation to make essential surgeries available. There is a paucity of data on outcomes following procedural sedation for surgery in Africa. We investigated the postoperative outcomes following procedural sedation by nonphysicians and physicians in Africa. We hypothesized that the level of training of the sedation provider may be associated with the incidence of severe postoperative complications and death. A secondary analysis of a prospective cohort of inhospital adult surgical patients representing 25 African countries was performed. The primary outcome was a collapsed composite of inhospital severe postoperative complications and death. We assessed the association between receiving procedural sedation conducted by a nonphysician (versus physician) and the composite outcome using logistic regression. We used the inverse probability of treatment weighting propensity score method to adjust for potential confounding variables including patient age, hemoglobin level, American Society of Anesthesiologists (ASA) physiological status, diabetes mellitus, urgency of surgery, severity of surgery, indication for surgery, surgical discipline, seniority of the surgical team, hospital level of specialization, and hospital funding system using public or private funding. All patients who only received procedural sedation for surgery were included. Three hundred thirty-six patients met the inclusion criteria, of which 98 (29.2%) received sedation from a nonphysician provider. The incidence of severe postoperative complications and death was 10 of 98 (10.2%) in the nonphysician group and 5 of 238 (2.1%) in the physician group. The estimated association between procedural sedation conducted by a nonphysician provider and inhospital outcomes was an 8-fold increase in the odds of severe complications and/or death, with an odds ratio (95% confidence interval [CI]) of 8.3 (2.7-25.6). The modest number of observations in this secondary data analysis suggests that shifting the task of procedural sedation from physicians to nonphysicians to increase access to care may be associated with severe postoperative complications and death in Africa. Research focusing on identifying factors contributing to adverse outcomes associated with procedural sedation is necessary to make this practice safer.

Towards the quantification of perioperative cardiovascular risk in the African context: A sub-analysis of the South African Surgical Outcomes Study and the African Surgical Outcomes Study.

The burden of cardiovascular disease in patients requiring non-cardiac surgery in Africa is not known. These patients are at increased risk for postoperative cardiovascular complications. In this sub-study, to use data on comorbidities and surgical outcomes from two large observational studies, the South African Surgical Outcomes Study (SASOS) and the African Surgical Outcomes Study (ASOS), to investigate the prevalence of cardiovascular disease in elective surgical patients and the risk of postoperative cardiovascular complications in this population. SASOS and ASOS were both prospective, observational cohort studies that collected data over 1 week in each participating centre. The primary outcome was in-hospital postoperative complications, which included prespecified and defined cardiovascular complications. We defined the cardiovascular disease burden of patients aged ≥45 years presenting for surgery (main objective), determined the relative risk of developing postoperative cardiovascular complications (secondary objective) and assessed the utility of the Revised Cardiac Risk Index (RCRI) for preoperative cardiovascular risk stratification of elective, non-cardiac surgical patients in Africa (third objective). The primary outcome analysis of 3 045 patients showed that patients with major cardiac complications were significantly older, with a higher prevalence of hypertension, coronary artery disease or congestive cardiac failure, and had undergone major surgery. In-hospital mortality for the cohort was 1.2%. The substantial burden of cardiovascular disease in patients presenting for non-cardiac surgery in Africa is shown in the principal findings of this study. The RCRI has moderate discrimination for major cardiac complications and major adverse cardiac events in African patients undergoing non-cardiac surgery.

Implementation of a Surgical Critical Care Service Reduces Failure to Rescue in Emergency Gastrointestinal Surgery in Rural Kenya.

We aimed to evaluate the implementation of a dedicated Surgical critical care service (SCCS) on failure to rescue (FTR) rates in rural Kenya. FTR adversely impacts perioperative outcomes. In the resource-limited contexts of low- and middle-income countries, emergency gastrointestinal surgery carries high morbidity and mortality rates. Quality improvement initiatives that decrease FTR rates are essential for improving perioperative care. All patients who underwent emergency gastrointestinal surgery between January 2016 and June 2019 at Tenwek Hospital in rural Kenya were reviewed. Critical care capabilities were constant throughout the study period. A supervised surgical resident was dedicated to the daily care of critically ill surgical patients beginning in January 2018. The impact of the SCCS initiation on the outcome of FTR was evaluated, controlling for patient complexity via the African Surgical Outcomes Study Surgical Risk Score. A total of 484 patients were identified, consisting of 278 without and 206 with an active SCCS. A total of 165 (34.1%) patients experienced postoperative complications, including 49 mortalities (10.1%) yielding an FTR rate of 29.7%. The FTR rate decreased after SCCS implementation from 36.8% (95% CI: 26.7%-47.8%) to 21.8% (95% CI: 13.2%-32.6%) ( P = 0.035) despite an increase in the average patient African Surgical Outcomes Study score from 14.5 (95% CI, 14.1-14.9) to 15.2 (95% CI, 14.7-15.7) ( P =0.03). The implementation of an SCCS in rural Kenya resulted in decreased rates of FTR despite an increase in patient complexity and severity of critical illness.

Real-world implementation challenges in low-resource settings

Real-world implementation challenges in low-resource settings

Enhanced postoperative surveillance versus standard of care to reduce mortality among adult surgical patients in Africa (ASOS-2): a cluster-randomised controlled trial

SummaryBackgroundRisk of mortality following surgery in patients across Africa is twice as high as the global average. Most of these deaths occur on hospital wards after the surgery itself. We aimed to assess whether enhanced postoperative surveillance of adult surgical patients at high risk of postoperative morbidity or mortality in Africa could reduce 30-day in-hospital mortality.MethodsWe did a two-arm, open-label, cluster-randomised trial of hospitals (clusters) across Africa. Hospitals were eligible if they provided surgery with an overnight postoperative admission. Hospitals were randomly assigned through minimisation in recruitment blocks (1:1) to provide patients with either a package of enhanced postoperative surveillance interventions (admitting the patient to higher care ward, increasing the frequency of postoperative nursing observations, assigning the patient to a bed in view of the nursing station, allowing family members to stay in the ward, and placing a postoperative surveillance guide at the bedside) for those at high risk (ie, with African Surgical Outcomes Study Surgical Risk Calculator scores ≥10) and usual care for those at low risk (intervention group), or for all patients to receive usual postoperative care (control group). Health-care providers and participants were not masked, but data assessors were. The primary outcome was 30-day in-hospital mortality of patients at low and high risk, measured at the participant level. All analyses were done as allocated (by cluster) in all patients with available data. This trial is registered with ClinicalTrials.gov, NCT03853824.FindingsBetween May 3, 2019, and July 27, 2020, 594 eligible hospitals indicated a desire to participate across 33 African countries; 332 (56%) were able to recruit participants and were included in analyses. We allocated 160 hospitals (13 275 patients) to provide enhanced postoperative surveillance and 172 hospitals (15 617 patients) to provide standard care. The mean age of participants was 37·1 years (SD 15·5) and 20 039 (69·4%) of 28 892 patients were women. 30-day in-hospital mortality occurred in 169 (1·3%) of 12 970 patients with mortality data in the intervention group and in 193 (1·3%) of 15 242 patients with mortality data in the control group (relative risk 0·96, 95% CI 0·69–1·33; p=0·79). 45 (0·2%) of 22 031 patients at low risk and 309 (5·6%) of 5500 patients at high risk died. No harms associated with either intervention were reported.InterpretationThis intervention package did not decrease 30-day in-hospital mortality among surgical patients in Africa at high risk of postoperative morbidity or mortality. Further research is needed to develop interventions that prevent death from surgical complications in resource-limited hospitals across Africa.FundingBill & Melinda Gates Foundation and the World Federation of Societies of Anaesthesiologists.TranslationsFor the Arabic, French and Portuguese translations of the abstract see Supplementary Materials section.

Development of a Clinical Prediction Model for In‐hospital Mortality from the South African Cohort of the African Surgical Outcomes Study

Data on the factors that influence mortality after surgery in South Africa are scarce, and neither these data nor data on risk-adjusted in-hospital mortality after surgery are routinely collected. Predictors related to the context or setting of surgical care delivery may also provide insight into variation in practice. Variation must be addressed when planning for improvement of risk-adjusted outcomes. Our objective was to identify the factors predicting in-hospital mortality after surgery in South Africa from available data. A multivariable logistic regression model was developed to identify predictors of 30-day in-hospital mortality in surgical patients in South Africa. Data from the South African contribution to the African Surgical Outcomes Study were used and included 3800 cases from 51 hospitals. A forward stepwise regression technique was then employed to select for possible predictors prior to model specification. Model performance was evaluated by assessing calibration and discrimination. The South African Surgical Outcomes Study cohort was used to validate the model. Variables found to predict 30-day in-hospital mortality were age, American Society of Anesthesiologists Physical Status category, urgent or emergent surgery, major surgery, and gastrointestinal-, head and neck-, thoracic- and neurosurgery. The area under the receiver operating curve or c-statistic was 0.859 (95% confidence interval: 0.827-0.892) for the full model. Calibration, as assessed using a calibration plot, was acceptable. Performance was similar in the validation cohort as compared to the derivation cohort. The prediction model did not include factors that can explain how the context of care influences post-operative mortality in South Africa. It does, however, provide a basis for reporting risk-adjusted perioperative mortality rate in the future, and identifies the types of surgery to be prioritised in quality improvement projects at a local or national level.

Africa’s critical care capacity before COVID-19

Critical care capabilities in affluent countries have been overwhelmed by the 2019 novel coronavirus disease (COVID-19) pandemic. Data from the African Surgical Outcomes Study (ASOS)1 suggests that this critical care crisis will be significantly worse in Africa.

Ensuring safe surgical care across resource settings via surgical outcomes data & quality improvement initiatives.

Staggering statistics regarding the global burden of disease due to lack of surgical care worldwide has been gaining attention in the global health literature over the last 10 years. The Lancet Commission on Global Surgery reported that 16.9 million lives were lost due to an absence of surgical care in 2010, equivalent to 33% of all deaths worldwide. Although data from low- and middle-income countries (LMICs) are limited, recent investigations, such as the African Surgical Outcomes Study, highlight that despite operating on low risk patients, there is increased postoperative mortality in LMICs versus higher-resource settings, a majority of which occur secondary to seemingly preventable complications like surgical site infections. We propose that implementing creative, low-cost surgical outcomes monitoring and select quality improvement systems proven effective in high-income countries, such as surgical infection prevention programs and safety checklists, can enhance the delivery of safe surgical care in existing LMIC surgical systems. While efforts to initiate and expand surgical access and capacity continues to deserve attention in the global health community, here we advocate for creative modifications to current service structures, such as promoting a culture of safety, employing technology and mobile health (mHealth) for patient data collection and follow-up, and harnessing partnerships for information sharing, to create a framework for improving morbidity and mortality in responsible, scalable, and sustainable ways.

Nigerian surgical outcomes - Report of a 7-day prospective cohort study and external validation of the African surgical outcomes study surgical risk calculator.

Surgical outcomes study for individual nations remains important because of international differences in patterns of surgical disease. We aimed to contribute to data on post-operative complications, critical care admissions and mortality following elective surgery in Nigeria and also validate the African Surgical Outcomes Study (ASOS) surgical risk calculator in our adult patient cohort. We conducted a 7-day, national prospective observational cohort study in consented consecutive patients undergoing elective surgery with a planned overnight hospital stay following elective surgery during a seven-day study period. The outcome measures were in-hospital postoperative complications, critical care admissions and in-hospital mortality censored at 30 days. Also, we identified variables which significantly contributed to higher ASOS surgical risk score. External validation was performed using area under the receiver operating characteristic curve (ROC) for discrimination assessment and Hosmer-Lemeshow test for calibration. A total of 1,425 patients from 79 hospitals participated in the study. Postoperative complications occurred in 264(18.5%, 95% CI 16.6-20.6), 20(7.6%) of whom were admitted into the ICU and 16(6.0%) did not survive. Total ICU admission was 57 (4%), with mortality rate of 23.5% following planned admission and overall in-hospital death was 22(1.5%, 95% CI 0.9-2.2). All prognostic factors in the ASOS risk calculator were significantly associated with higher ASOS score and the scoring system showed moderate discrimination (0⋅73, 95% CI 0.62-0.83). Hosmer-Lemeshow χ2 test revealed scale was well calibrated in the validation cohort. NiSOS validates the findings of ASOS and the ability of the ASOS surgical risk calculator to predict risk of developing severe postoperative complications and mortality. We identified failure-to-rescue as a problem in Nigeria. Furthermore, this study has provided policy makers with benchmarks that can be used to monitor programmes aimed at reducing the morbidity and mortality after elective surgery. We recommend the adoption of the ASOS surgical risk calculator as a tool for risk stratification preoperatively for elective surgery.

Maternal and neonatal outcomes after caesarean delivery in the African Surgical Outcomes Study: a 7-day prospective observational cohort study

Maternal and neonatal mortality is high in Africa, but few large, prospective studies have been done to investigate the risk factors associated with these poor maternal and neonatal outcomes. A 7-day, international, prospective, observational cohort study was done in patients having caesarean delivery in 183 hospitals across 22 countries in Africa. The inclusion criteria were all consecutive patients (aged ≥18 years) admitted to participating centres having elective and non-elective caesarean delivery during the 7-day study cohort period. To ensure a representative sample, each hospital had to provide data for 90% of the eligible patients during the recruitment week. The primary outcome was in-hospital maternal mortality and complications, which were assessed by local investigators. The study was registered on the South African National Health Research Database, number KZ_2015RP7_22, and on ClinicalTrials.gov, number NCT03044899. Between February, 2016, and May, 2016, 3792 patients were recruited from hospitals across Africa. 3685 were included in the postoperative complications analysis (107 missing data) and 3684 were included in the maternal mortality analysis (108 missing data). These hospitals had a combined number of specialist surgeons, obstetricians, and anaesthetists totalling 0·7 per 100 000 population (IQR 0·2-2·0). Maternal mortality was 20 (0·5%) of 3684 patients (95% CI 0·3-0·8). Complications occurred in 633 (17·4%) of 3636 mothers (16·2-18·6), which were predominantly severe intraoperative and postoperative bleeding (136 [3·8%] of 3612 mothers). Maternal mortality was independently associated with a preoperative presentation of placenta praevia, placental abruption, ruptured uterus, antepartum haemorrhage (odds ratio 4·47 [95% CI 1·46-13·65]), and perioperative severe obstetric haemorrhage (5·87 [1·99-17·34]) or anaesthesia complications (11·47 (1·20-109·20]). Neonatal mortality was 153 (4·4%) of 3506 infants (95% CI 3·7-5·0). Maternal mortality after caesarean delivery in Africa is 50 times higher than that of high-income countries and is driven by peripartum haemorrhage and anaesthesia complications. Neonatal mortality is double the global average. Early identification and appropriate management of mothers at risk of peripartum haemorrhage might improve maternal and neonatal outcomes in Africa. Medical Research Council of South Africa.

The African Surgical OutcomeS-2 (ASOS-2) Pilot Trial, a mixed-methods implementation study

Background: The African Surgical Outcomes Study (ASOS) showed that surgical patients in Africa have a mortality twice the global average. The working hypothesis is that patients die as a result of failure to rescue following complications in the postoperative period. The African Surgical OutcomeS-2 (ASOS-2) Trial plans to test the efficacy of increased postoperative surveillance in high risk patients for decreasing perioperative morbidity and mortality. This pilot trial aimed i) to evaluate the adequacy of data produced by the data collection strategies of the ASOS-2 Trial, ii) to evaluate the fidelity of implementation of the increased postoperative surveillance intervention, and iii) to understand the acceptability, appropriateness and feasibility of the intervention and the trial processes. Methods: The ASOS-2 Pilot Trial was a mixed-methods (quantitative-qualitative) implementation study focusing on the intervention arm of the proposed ASOS-2 Trial. The intervention is increased postoperative surveillance for high-risk surgical patients. The intervention protocol was implemented at all sites for a seven-day period. A post pilot trial survey was used to collect data on the implementation outcomes. Results: 803 patients were recruited from 16 hospitals in eight African countries. The sampling and data collection strategies provided 98% complete data collection. Seventy-three percent of respondents believed that they truly provided increased postoperative surveillance to high risk patients. In reality 83/125 (66%) of high-risk patients received some form of increased postoperative surveillance. However, the individual components of the increased postoperative surveillance intervention were implemented in less than 50% of high-risk patients (excepting increasing nursing observations). The components most frequently unavailable were the ability to provide care in a higher care ward (32.1%) and assigning the patient to a bed in view of the nurses’ station (28.4%). Failure to comply with available components of the intervention ranged from 27.5% to 54.3%. The post pilot survey had a response rate of 30/40 (75%). In Likert scale questions about acceptability, appropriateness, and feasibility of the ASOS-2 intervention, 63% to 87% of respondents indicated agreement. Respondents reported barriers related to resources, trial processes, teamwork and communication as reasons for disagreement. Conclusions: The proposed ASOS-2 Trial appears to be appropriate, acceptable and feasible in Africa. This pilot trial provides support for the proposed ASOS-2 Trial. It emphasises the need for establishing trial site teams which address the needs of all stakeholders during the trial. A concerted effort must be made to help participating hospitals to increase compliance with all the components of the proposed intervention of ‘increased postoperative surveillance’ during the ASOS-2 Trial.

Preoperative anaemia and clinical outcomes in the South African Surgical Outcomes Study.

In high-income countries, preoperative anaemia has been associated with poor postoperative outcomes. To date, no large study has investigated this association in South Africa (SA). The demographics of SA surgical patients differ from those of surgical patients in the European and Northern American settings from which the preoperative anaemia data were derived. These associations between preoperative anaemia and postoperative outcomes are therefore not necessarily transferable to SA surgical patients. The primary objective was to determine the association between preoperative anaemia and in-hospital mortality in SA adult non-cardiac, non-obstetric patients. The secondary objectives were to describe the association between preoperative anaemia and (i) critical care admission and (ii) length of hospital stay, and the prevalence of preoperative anaemia in adult SA surgical patients. We performed a secondary analysis of the South African Surgical Outcomes Study (SASOS), a large prospective observational study of patients undergoing inpatient non-cardiac, non-obstetric surgery at 50 hospitals across SA over a 1-week period. To determine whether preoperative anaemia is independently associated with mortality or admission to critical care following surgery, we conducted a multivariate logistic regression analysis that included all the independent predictors of mortality and admission to critical care identified in the original SASOS model. The prevalence of preoperative anaemia was 1 727/3 610 (47.8%). Preoperative anaemia was independently associated with in-hospital mortality (odds ratio (OR) 1.657, 95% confidence interval (CI) 1.055 - 2.602; p=0.028) and admission to critical care (OR 1.487, 95% CI 1.081 - 2.046; p=0.015). Almost 50% of patients undergoing surgery at government-funded hospitals in SA had preoperative anaemia, which was independently associated with postoperative mortality and critical care admission. These numbers indicate a significant perioperative risk, with a clear need for quality improvement programmes that may improve surgical outcomes. Long waiting lists for elective surgery allow time for assessment and correction of anaemia preoperatively. With a high proportion of patients presenting for urgent or emergency surgery, perioperative clinicians in all specialties should educate themselves in the principles of patient blood management.

Preoperative serum sodium measurements and postoperative inpatient mortality: A case-control analysis of data from the South African Surgical Outcomes Study

Abnormal preoperative serum sodium measurements have been shown to be associated with increased postoperative mortality in US and European surgical populations. It is possible that such measurements are also associated with increased postoperative mortality in a South African (SA) setting, but this is yet to be confirmed. Establishing whether preoperative serum sodium measurements are associated with postoperative mortality could have implications for perioperative risk stratification in SA settings. To determine whether preoperative serum sodium measurements are associated with postoperative mortality in SA surgical patients. This was an unmatched case-control study of patient data (demographics, comorbidities, procedure-related variables, and preoperative serum sodium measurements) collected during the South African Surgical Outcomes Study. Data were analysed using recommended statistical methods for unmatched case-control studies. The study population comprised 103 patients and 410 controls. Cases were defined as patients who suffered postoperative inpatient mortality, while controls were defined as patients who did not suffer postoperative inpatient mortality. Preoperative hypernatraemia (i.e. a preoperative serum sodium measurement &gt;144 mEq/L) was independently associated with a four-fold higher risk of postoperative inpatient mortality compared with a normal preoperative serum sodium measurement of 135 - 144 mEq/L (odds ratio (OR) 4.21, 95% confidence interval (CI) 1.19 - 14.83, p=0.025). Preoperative hyponatraemia (i.e. a preoperative serum sodium measurement &lt;135 mEq/L) was not independently associated with a higher or lower risk of postoperative inpatient mortality compared with a normal preoperative serum sodium measurement (OR 1.39, 95% CI 0.70 - 2.76, p=0.346). Preoperative hypernatraemia, but not preoperative hyponatraemia, is a risk factor for postoperative inpatient mortality in SA surgical patients.

The ASOS Surgical Risk Calculator: development and validation of a tool for identifying African surgical patients at risk of severe postoperative complications

BackgroundThe African Surgical Outcomes Study (ASOS) showed that surgical patients in Africa have a mortality twice the global average. Existing risk assessment tools are not valid for use in this population because the pattern of risk for poor outcomes differs from high-income countries. The objective of this study was to derive and validate a simple, preoperative risk stratification tool to identify African surgical patients at risk for in-hospital postoperative mortality and severe complications. MethodsASOS was a 7-day prospective cohort study of adult patients undergoing surgery in Africa. The ASOS Surgical Risk Calculator was constructed with a multivariable logistic regression model for the outcome of in-hospital mortality and severe postoperative complications. The following preoperative risk factors were entered into the model; age, sex, smoking status, ASA physical status, preoperative chronic comorbid conditions, indication for surgery, urgency, severity, and type of surgery. ResultsThe model was derived from 8799 patients from 168 African hospitals. The composite outcome of severe postoperative complications and death occurred in 423/8799 (4.8%) patients. The ASOS Surgical Risk Calculator includes the following risk factors: age, ASA physical status, indication for surgery, urgency, severity, and type of surgery. The model showed good discrimination with an area under the receiver operating characteristic curve of 0.805 and good calibration with c-statistic corrected for optimism of 0.784. ConclusionsThis simple preoperative risk calculator could be used to identify high-risk surgical patients in African hospitals and facilitate increased postoperative surveillance. Clinical trial registrationNCT03044899.

Barriers to clinical research in Africa: a quantitative and qualitative survey of clinical researchers in 27 African countries

BackgroundThere is a need for high quality research to improve perioperative patient care in Africa. The aim of this study was to understand the particular barriers to clinical research in this environment. MethodsWe conducted an electronic survey of African Surgical Outcomes Study (ASOS) investigators, including 29 quantitative Likert scale questions and eight qualitative questions with subsequent thematic analysis. Protocol compliant and non-compliant countries were compared according to WHO statistics for research and development, health workforce data, and world internet statistics. ResultsResponses were received from 134/418 of invited researchers in 24/25 (96%) of participating countries, and three non-participating countries. Barriers included lack of a dedicated research team (47.7%), reliable internet access (32.6%), staff skilled in research (31.8%), and team commitment (23.8%). Protocol compliant countries had significantly more physicians per 1000 population (4 vs 0.9, P<0.01), internet penetration (38% vs 28%, P=0.01) and published clinical trials (1461 vs 208, P<0.01) compared with non-compliant countries. Facilitators of research included establishing a research culture (86.9%), simple data collection tools (80%), and ASOS team interaction (77.9%). Most participants are interested in future research (93.8%). Qualitative data reiterated human resource, financial resource, and regulatory barriers. However, the desire to contribute to an African collaboration producing relevant data to improve patient outcomes was expressed strongly by ASOS investigators. ConclusionsBarriers to successful participation in ASOS related to resource limitations and not motivation of the clinician investigators. Practical solutions to individual barriers may increase the success of multi-centre perioperative research in Africa.

Perioperative patient outcomes in the African Surgical Outcomes Study: a 7-day prospective observational cohort study

There is a need to increase access to surgical treatments in African countries, but perioperative complications represent a major global health-care burden. There are few studies describing surgical outcomes in Africa. We did a 7-day, international, prospective, observational cohort study of patients aged 18 years and older undergoing any inpatient surgery in 25 countries in Africa (the African Surgical Outcomes Study). We aimed to recruit as many hospitals as possible using a convenience sampling survey, and required data from at least ten hospitals per country (or half the surgical centres if there were fewer than ten hospitals) and data for at least 90% of eligible patients from each site. Each country selected one recruitment week between February and May, 2016. The primary outcome was in-hospital postoperative complications, assessed according to predefined criteria and graded as mild, moderate, or severe. Data were presented as median (IQR), mean (SD), or n (%), and compared using t tests. This study is registered on the South African National Health Research Database (KZ_2015RP7_22) and ClinicalTrials.gov (NCT03044899). We recruited 11 422 patients (median 29 [IQR 10-70]) from 247 hospitals during the national cohort weeks. Hospitals served a median population of 810 000 people (IQR 200 000-2 000 000), with a combined number of specialist surgeons, obstetricians, and anaesthetists totalling 0·7 (0·2-1·9) per 100 000 population. Hospitals did a median of 212 (IQR 65-578) surgical procedures per 100 000 population each year. Patients were younger (mean age 38·5 years [SD 16·1]), with a lower risk profile (American Society of Anesthesiologists median score 1 [IQR 1-2]) than reported in high-income countries. 1253 (11%) patients were infected with HIV, 6504 procedures (57%) were urgent or emergent, and the most common procedure was caesarean delivery (3792 patients, 33%). Postoperative complications occurred in 1977 (18·2%, 95% CI 17·4-18·9]) of 10 885 patients. 239 (2·1%) of 11 193 patients died, 225 (94·1%) after the day of surgery. Infection was the most common complication (1156 [10·2%] of 10 970 patients), of whom 112 (9·7%) died. Despite a low-risk profile and few postoperative complications, patients in Africa were twice as likely to die after surgery when compared with the global average for postoperative deaths. Initiatives to increase access to surgical treatments in Africa therefore should be coupled with improved surveillance for deteriorating physiology in patients who develop postoperative complications, and the resources necessary to achieve this objective. Medical Research Council of South Africa.

The South African Surgical Outcomes Study: A 7-day prospective observational cohort study.

Non-cardiac surgical morbidity and mortality is a major global public health burden. Sub-Saharan African perioperative outcome data are scarce. South Africa (SA) faces a unique public health challenge, engulfed as it is by four simultaneous epidemics: (i) poverty-related diseases; (ii) non-communicable diseases; (iii) HIV and related diseases; and (iv) injury and violence. Understanding the effects of these epidemics on perioperative outcomes may provide an important perspective on the surgical health of the country. To investigate the perioperative mortality and need for critical care admission in patients undergoing inpatient non-cardiac surgery in SA. A 7-day national, multicentre, prospective, observational cohort study of all patients ≥16 years of age undergoing inpatient non-cardiac surgery between 19 and 26 May 2014 at 50 public sector, government-funded hospitals in SA. The study included 3 927/4 021 eligible patients (97.7%) recruited, with 45/50 hospitals (90.0%) submitting data that described all eligible patients. Crude in-hospital mortality was 123/3 927 (3.1%; 95% confidence interval (CI) 2.6 - 3.7). The rate of postoperative admission to critical care units was 255/3,927 (6.5%; 95% CI 5.7 - 7.3), with 43.5% of admissions being unplanned. Of the surgical procedures 2,120/3,915 (54.2%) were urgent or emergency ones, with a population-attributable risk for mortality of 25.5% (95% CI 5.1 - 55.8) and a risk of admission to critical care of 23.7% (95% CI 4.7 - 51.4). Most patients in SA's public sector hospitals undergo urgent and emergency surgery, which is strongly associated with mortality and unplanned critical care admissions. Non-communicable diseases have a larger proportional contribution to mortality than infections and injuries. However, the most common comorbidity, HIV infection, was not associated with in-hospital mortality. The study was registered on ClinicalTrials.gov (NCT02141867).