Interhospital transfer for emergency surgery significantly increases postoperative mortality and morbidity risks in adult patients

This systematic review and random-effects meta-analysis examined a colossal cohort of 2,863,773 adult patients undergoing emergency general surgery operations. The study compared outcomes between those admitted directly to the hospital versus those transferred from other facilities. The primary focus was on postoperative mortality, while secondary analyses assessed postoperative morbidity. The follow-up period extended for 30 days to capture early surgical complications and deaths effectively.

Unadjusted analysis showed a stark disparity, with transferred patients facing significantly higher postoperative mortality. The odds ratio reached 2.55, indicating a more than twofold increase in death risk compared to direct admissions. This difference was statistically significant with a p-value less than 0.001. When researchers adjusted for potential confounding variables, the elevated mortality risk persisted, though the odds ratio decreased slightly to 1.26. Even after adjustment, the p-value remained significant at 0.008, confirming that transfer status independently predicts worse survival outcomes.

Postoperative morbidity followed a similar concerning trend. Unadjusted data revealed an odds ratio of 2.06 for complications in transferred patients, with a highly significant p-value of 0.0003. Adjusted analysis still demonstrated a 31% increase in the odds of morbidity (OR: 1.31, P = 0.003). These findings suggest that the transfer process itself, or the underlying conditions necessitating transfer, substantially elevates the risk of surgical complications.

Demographic and clinical characteristics further illuminate the reasons behind these disparities. Transferred patients were, on average, 5.91 years older than those admitted directly. The proportion of patients with an American Society of Anesthesiologists (ASA) score of 3 or higher was markedly higher in the transfer group, with an odds ratio of 2.45. This indicates that sicker, more critically ill patients are more likely to be transferred, which inherently increases risk.

Surgical complexity also differed significantly between the two groups. Procedures such as small bowel resections, colectomies, and repairs for perforated peptic ulcers were more common in the transferred population. Conversely, appendectomies, which are generally less complex, were more frequent in the direct admission group. The odds of undergoing a small bowel resection were 1.49 times higher in transferred patients, while colectomies were 1.72 times more likely. These data points suggest that the decision to transfer often involves patients requiring more intricate surgical interventions.

The limitations of observational data must be acknowledged. The association between transfer and poor outcomes may stem from selection bias, where sicker patients are transferred due to lack of local resources. Transfer-related delays in definitive care could also contribute to the observed risks. However, the consistency of the findings across unadjusted and adjusted models strengthens the conclusion that interhospital transfer is a negative prognostic factor. Clinicians should weigh the necessity of transfer against the potential for increased mortality and morbidity.

In conclusion, this extensive analysis provides robust evidence that interhospital transfer is associated with increased risks in emergency general surgery. The data supports viewing transfer status as a marker for higher postoperative mortality and morbidity. Healthcare systems should evaluate the necessity of transfers carefully, ensuring that the benefits outweigh the documented risks. Future research should aim to isolate specific mechanisms driving these adverse outcomes to inform better triage and transfer protocols.