Defining the optimal time to appendectomy: A step toward precision surgery.

BACKGROUND: We aimed to investigate the association between time from admission to appendectomy on perioperative outcomes in order to determine optimal time-to-surgery windows. METHODS: We performed a retrospective review of all the appendectomies performed between July 2018 to May 2020. We first compared the perioperative outcomes using preselected time-to-surgery cut-offs, then determined optimal safe windows for surgery, and finally identified subgroups of patients who may require early intervention. RESULTS: Six hundred twenty-one appendectomies were performed in the time period. The patients with a time-to-surgery of ≥12 hours had a significantly longer length of stay (median 2 days [interquartile range 1-3] vs 3 days [interquartile range 2-4], mean difference = 0.74 [95% confidence interval 0.32-1.17, P = .0006]) and higher 30-day readmission risk (odds ratio 2.58, 95% confidence interval 1.12-5.96, P = .0266) versus those with a time-to-surgery of <12 hours. These differences persisted when the time-to-surgery was dichotomized by <24 or ≥24 hours. A time-to-surgery beyond 25 hours was associated with a 3.34-fold increased odds of open conversion (P = .040), longer operation time (mean difference 15.8 mins, 95% confidence interval 3.4-28.3, P = .013) and longer postoperative length of stay (mean difference 10.3 hours, 95% confidence interval 3.4-20.2, P = .042) versus a time-to-surgery of <25 hours. The patients with time-to-surgery beyond 11 hours had a 1.35-fold increased odds of 30-day readmission (95% confidence interval 1.02-5.43, P = .046) compared with those who underwent appendectomy before 11 hours. Older patients, patients with American Society of Anesthesiologist score II to III, and individuals with long duration of preadmission symptoms had higher risk of prolonged operation time, open conversion, increased length of stay, and postoperative morbidity with increasing time-to-surgery. CONCLUSION: This study identified the safe windows for appendectomy to be 11 to 25 hours from admission for most perioperative outcomes. However, certain patient subgroups may be less tolerant of surgical delays.

Validation of the modified Ranson versus Glasgow score for pancreatitis in a Singaporean population.

BACKGROUND: The characteristics of patients with acute pancreatitis in multi-ethnic Singapore differ from that of the populations used in formulating the modified Ranson and Glasgow scores. The use of these scoring systems has not previously been validated in the Singaporean setting. This study aims to validate and compare the prognostic use of the modified Ranson and Glasgow scores, and to determine the superiority of one score over the other in predicting the outcome for acute pancreatitis in the Singaporean population. METHODS: This is a 3-year retrospective study of patients diagnosed with acute pancreatitis at our centre. Patients with chronic pancreatitis, acute on chronic pancreatitis, iatrogenic pancreatitis, pancreatic cancer as well as those with incomplete Ranson or Glasgow scores were excluded from the study. Case notes and computer records were reviewed for local complications of pancreatitis and organ failure. Receiver operator characteristic (ROC) curves of the Ranson and Glasgow scores were plotted for the prediction of severity and mortality. RESULTS: Between January 2010 and December 2012, 230 cases were diagnosed with acute pancreatitis. A majority of the patients had mild pancreatitis (n = 194, 84.3%), and the overall 30-day mortality rate was 3.5% (n = 8). ROC of the Ranson and Glasgow scoring systems for mortality showed an area under curve (AUC) of 0.854 (P = 0.001) and 0.776 (P = 0.008), respectively. For severity, the AUC for the modified Ranson and Glasgow score was calculated to be 0.694 and 0.668, respectively. CONCLUSIONS: The ROC curves of Ranson and Glasgow scores for mortality are comparable with that published in earlier studies. In a Singaporean population, the Ranson score is more accurate in the prediction of mortality. However, both scoring systems are poor predictors for severity of acute pancreatitis.