Background and Goal of Study: Even after recent advances of modern anaesthetic managements, incidence of postoperative adverse events (SAEs) have been still reported to be 10-15%. To decrease hospital mortality, not only early detection and treatment of SAEs, but also prediction of SAEs is clearly needed.
However, prediction of SAEs is difficult. We normally used American society of anesthesiologists physical status (ASA-PS) for preoperative patients' assessment, but its ability to predict postoperative SAEs is not clear. Accordingly, we compared POSSUM and Charlson scoring systems and ASA-PS to predict postoperative SAEs.
Materials and Methods: We prospectively studied 200 patients underwent major surgery in a teaching hospital from March to June 2012. Major surgery was defined as craniotomy, neck surgery, thoracotomy, laparotomy, hip or pelvic surgery, and spinal surgery. We excluded patients < 20 years old age and operation < 2 hrs.
We calculated ASA-PS, POSSUM score and Charlson score, and checked the actual occurrence of SAEs by patients' follow-up during their hospital stay. We prospectively defined the 13 SAEs such as severe sepsis, ICU readmission, respiratory failure, cardiac arrest, unexpected tracheostomy, cerebrovascular accident, deep venous thromboembolism and ICU stay over 2 weeks etc.
We calculated discriminational abilities of the scores using receiver operating characterisctics (ROC) curve methods describing their area under the curves (AUROC). Data were expressed as means with 95% confidence intervals (CI). A p value < 0.05 was considered statistically significant.
Results and Discussion: Among 200 patients studied, 25 patients suffered from SAEs postoperatively. The incidence of SAEs was 12.5%. Compared to the non SAEs patients, the SAEs patients had higher POSSUM operative score (OS) (16.76 vs 13.69; p=0.0002) and Charson score (4.16 vs 2.70; p=0.0026), but ASA-PS were not significantly different (2.16 vs 1.99; p=0.2443) between the groups. The AUROCs of three scores were ASA PS 0.57, POSSUM OS 0.71, and Charlson score 0.66, respectively. No combinations increase predictability of SAEs compared to POSSUM OS only.
Conclusion(s): Substantial numbers of SAEs occurred postoperatively as high as 12.5%.
POSSUM Operative Score is useful for predicting postoperative serious adverse events rather than other scores.