The anaesthetic assessment, management and risk factors of bariatric surgical patients requiring postoperative intensive care support: a state-wide, five-year cohort study.

Bariatric surgery is a rapidly growing and dynamic discipline necessitating a specialised anaesthetic approach coordinating high-risk patients with appropriate post-operative intensive care (ICU) support. The relationship between the anaesthetic and ICU utilisation after bariatric surgery is poorly understood. All adult bariatric surgery patients admitted to any ICU over a five-year period between 2007 and 2011 in Western Australia were identified from hospital admission records and cross-referenced against the Western Australian Department of Health Data Linkage Unit database. During the study period 12,062 patients under went bariatric surgery with 581 (4.8%) patients admitted to ICU immediately following surgery. The mean pre-operative ASA score was 3.3 [standard deviation 1.1] with 76.9% of patients were assessed by their anaesthetist for the first time on the day-of-surgery. Blood pathology (75%) and ECG (46.3%) were the most common preoperative investigations. Intra-operatively, 2.1% of patients had a grade 4 intubation with only 3.4% of patients requiring a videoscopic assisted intubation. Despite being deemed at high risk, 23.6% of patients were managed with 20 gauge or smaller intravenous access. Anaesthetic complications were extremely uncommon (0.5% of all bariatric cases) but accounted for 9.7% of all postoperative ICU admissions. Smoking history, but not body-mass-index (P=0.46), was the only significant prognostic factor for respiratory or airway related anaesthetic complications (P=0.012). In summary, the anaesthesia management of bariatric surgery varied widely in Western Australia, with smoking as the only significant preoperative risk factor for respiratory or airway related anaesthesia complications.