Reliability of Surgical Apgar Score (SAS) in predicting immediate post-operative extubation and intensive care unit admission after major abdominal surgeries: A single center three-year retrospective study

ABSTRACT

Background@#Surgical Apgar Score (SAS) is a simple, inexpensive, and readily available ten-point scoring system using patient's parameters which include surgical blood loss, lowest recorded mean arterial pressure (MAP) and lowest intraoperative heart rate in predicting 30-day post-operative morbidities. This study determined the reliability of SAS in predicting immediate post-operative extubation and immediate intensive care unit (ICU) admission among patients who underwent major abdominal surgeries in a tertiary hospital in Iloilo City.@*Methods@#A descriptive retrospective cross- sectional study conducted in a tertiary hospital in Iloilo City included patients aged 19 and above who underwent major abdominal surgery from January 1, 2017 to December 31, 2019, and met the study's inclusion criteria. Purposive sampling was utilized. Demographics, clinical data, intraoperative data, management as well as treatment course, post- operative course and patient outcome were extracted, and data collected were utilized for data processing and analysis. Frequency count, mean and standard deviation were utilized for descriptive statistics; T-test and One-way Analysis of Variance (ANOVA) were utilized to determine statistical difference among groups. Logistic regression analysis was employed to assess association between SAS and immediate extubation and post- op ICU admission. Statistical Package of the Social Sciences (SPSS) software version 23.0 was utilized for statistical computations. A probability level of p<0.05 was utilized to determine statistical significance.@*Results@#The study consisted of 221 patients predominantly female 64.3 % (n=142) with the mean age of 55.80 17.53. Mean SAS was 6.79 $ 1.3 with a total of 13 (5.9%) patients who were classified as high risk (SAS 0-4), 152 (68.8%) patients as medium risk (SAS 5-7) and 56 (25.3%) patients as low risk with SAS 8-10. On logistic regression analysis, mean arterial pressure (MAP), lowest heart rate and estimated blood loss were significantly associated with decision to do immediate post-operative extubation and immediate ICU admission (p<0.001). Those with higher MAP were 1.19 times more likely to be extubated (OR 1.199, CI 1.078-1.334, p<0.001) and higher estimated blood loss more likely to be admitted in the ICU (OR 1.006, CI 1.004-1.009, p<0.001). Lastly, those with higher heart rates were 1.2 times more likely to be admitted in the ICU post-operatively. Low-Risk SAS (Score of 8-10) is predictive of immediate post-operative extubation with 97.7% sensitivity and 75.6% specificity. High Risk SAS (score of 0-4) is predictive of immediate post-operative ICU admission with a sensitivity of 76.1% and 98.3% specificity.@*Conclusion@#SAS is a reliable and valid predictive tool in determining immediate post- operative extubation and ICU admission among patients undergoing major abdominal surgeries. Multicentric, longitudinal and prospective studies are further required to confirm results.Keywords Surgical Apgar Score (SAS), extubation, intensive care, critical care, abdominal surgery