Incidence, risk factors, and outcome of postoperative pneumonia after microsurgical clipping of ruptured intracranial aneurysms

BACKGROUND: Occurrence of pneumonia challenges the medical management of patients who have undergone surgery for aneurysmal subarachnoid hemorrhage, and is associated with significant mortality and morbidity. There are very few studies evaluating the incidence and outcome of postoperative pneumonia in patients undergoing microsurgical clipping of ruptured intracranial aneurysms. The aim of this study was to determine the incidence, risk factors, and outcome of postoperative pneumonia in patients undergoing surgery for ruptured intracranial aneurysms. METHODS: All patients operated for intracranial aneurysms, over a period of 9 months, were included prospectively. They were studied for risk factors predisposing them to pneumonia and their outcomes were noted at discharge. Patients with predisposing chronic lung disease, preexisting pneumonia, and chronic smoking habits were excluded. RESULTS: One hundred and three patients [Mean age: 46.01 years; M:F – 58:45] underwent microsurgical clipping of aneurysm during the study period. Of these, 28 patients (27.2%) developed postoperative pneumonia. The variables associated with postoperative pneumonia were: [Preoperative] age >50 years, Glasgow Coma Scale (GCS) at presentation <15 and Hunt and Hess grade before surgery >2; [postoperative] duration of surgery >3 hours, GCS <15 after complete reversal from anesthesia, duration of intubation in the postoperative period >48 hours, tracheostomy, postoperative ventilation, intensive care unit (ICU) stay >5 days. Predictive factors for postoperative pneumonia by multivariate analysis were: Postoperative endotracheal intubation >48 hours, tracheostomy and ICU stay >5 days. CONCLUSIONS: There is a high incidence of postoperative pneumonia and mortality associated with pneumonia (27.2% and 9.7%, respectively in our study) in patients of ruptured intracranial aneurysms undergoing microsurgical clipping at our center, with Acinetobacter species being the predominant causative organism.