Evaluation of O-POSSUM vs ASA and APACHE II scores in patients undergoing oesophageal surgery

Risk and prognostic scores quantify the patient's risk of death or complication according to the severity of his illness. The aim of this study was to evaluate the predictive accuracy of O-POSSUM vs ASA and APACHE II models on patients undergoing oesophageal surgery.

In this observational retrospective study 55 patients were enrolled who had undergone surgical interventions of excision and reconstruction of the oesophagus for neoplastic oesophageal stenosis, in the Surgical Clinics (I and II) of the Clinical County Emergency Hospital Mures, between January 2011 and January 2014. By using patients file records after extracting the data we calculated the predictive mortality, according to the prognostic scores O-POSSUM, ASA and APACHE II and we analyzed its correlations with the postoperative evolution. We evaluated the discriminatory power of the three scores using the ROC (receiver-operating characteristic) curves. According to the cut-off value corresponding to each score, we compared the Kaplan Meier survival curves during the hospitalization period.

ROC curves analysis revealed that O-POSSUM had a better discriminatory power for mortality compared to the other two scores: AUC = 0.73 for O-POSSUM, AUC = 0.57 for APACHE II and AUC = 0.64 for ASA (p < 0.001). The cut-off value was statistically significant only in case of O-POSSUM, as it derives from the statistical analysis of the survival curves (p = 0.035).

O-POSSUM predicts mortality more accurately compared to ASA or APACHE II in patients undergoing oesophageal surgery.