The Simple Prognostic Index (SPI)--a pathophysiologic prognostic scoring tool for emergency laparotomy

Laparotomy is commonly performed as an emergency operation. It is often performed on elderly patients with high risks of mortality and morbidity. Currently, there is no accurate scoring system to predict mortality and morbidity, preoperatively, in these circumstances. This study was conducted to develop a scoring system that can accurately predict the risk of in-hospital mortality and complications for these patients in the emergency department prior to surgery.

Middlemore Hospital data were searched for patients who underwent emergency laparotomy for an acute abdominal condition between January 1997 and December 2006. Data collected included age, gender, presenting diagnosis, indications for surgery, acute physiologic parameters, and also data on associated comorbidities. We categorized patients for the risk of morbidity and 30-d mortality. The risk categorization was based on preoperative existing comorbidities and acute disturbances of physiologic parameters. Regression analysis was used to correlate between acute laboratory parameters, patients age and gender, clinical premorbid conditions, and surgical procedures with the risk of mortality and rates of complications.

Emergency laparotomy was performed on 1712 patients. The median age was 58 and there were 896 male patients. Patients with one or two minor comorbidities had comparable mortality and complication rate to those with no comorbidities. There was high correlation between factors that denoted the onset of multiple organ failure with in-hospital mortality and complication rates. This allowed us to divide patients into four prognostic groups with increasing mortality and morbidity.

Mortality and morbidity after emergency laparotomy are closely related to the presence or absence of acute physiologic impairment and the presence or absence of chronic organ system failure. The Simple Prognostic Index (SPI) is a simple scoring system for prediction of mortality and morbidity prior to emergency laparotomy.