Unplanned postoperative reintubation (UPR) is an unexpected event that indicates an unfavourable postoperative course. It serves as a marker for severe adverse outcome after surgery, and is associated significant morbidity, mortality and healthcare cost. Indications for UPR have ranged from unexpected or failed extubation to clinical deterioration of patients after surgery. Previous studies have had specific populations which has limited their application to global practice.
Aim of the study
To examine the incidence, impact, and predictors of UPR in adult male and female patients undergoing general and vascular surgery at a large urban hospital to provide a more comprehensive analysis that supports the findings of previous studies, or perhaps identifies novel predictors of UPR, to allow for well-informed decisions among surgeons during the perioperative period.
Retrospective review of all general and vascular surgical cases from January 2013 – September 2016 in patients >18yrs old looking at 35 variables to identify predictors of UPR. The primary outcome was unplanned postoperative reintubation (UPR) within 30 days following general and vascular surgery. UPR was defined as the placement of an endotracheal tube or mechanical or assisted ventilation due to the onset of cardiopulmonary or respiratory failure, as manifested by severe respiratory distress, hypoxia, hypercarbia or respiratory acidosis.
8809 cases were analysed and 138 patients underwent UPR (1.6%). Following surgery, UPR was associated with a significantly increased mortality (OR 3.8, 95%CI 2.7–5.2, p < 0.01). The factors found to be associated with UPR were advanced, higher ASA status, CHF, acute renal failure or dialysis, weight loss, systemic sepsis, elevated preoperative creatinine, hypoalbuminemia, and anaemia.
Findings of this study suggest UPR is significantly associated increased morbidity and mortality after noncardiac surgery. Novel predictors contribute to UPR following noncardiac surgery. In addition to previously identified predictors of UPR, perioperative management aimed at decreasing UPR should target preoperative anaemia.
Key discussion points regarding the article:
- The study did analyse a large cohort of cases which are widely applicable to most departments caseload. They looked at a large number of potential contributing factors which are commonly found in this patient mix.
- They highlighted the relative rarity of re-intubation and their results were in-line with previous studies findings.
- However the there was no information about how complete their data set was, whether any cases were excluded, no data on when or where the patients were extubated, the timing of UPR or the numbers of patients that were in the HDU / ICU environment post-operatively.
- They also did not provide information as to how the regression analysis was undertaking making the significance of the data difficult to interpret.
- Their discussion primarily focussed on the impact of anaemia on the incidence of UPR but did not provide data on the numbers of patients analysed. The parameter for defining anaemia was changed from the initial haematocrit lab value of <38% to <34% raising the concern that they reanalysed the data until they reached statistical significance.
Unplanned postoperative reintubation is associated with significantly increased morbidity, mortality and increased length of hospital stay. This study did confirm the findings of previous studies in recognising that patients of increasing age, multiple co-morbidities and poor functional status are at increased risk although this is somewhat unsurprising. The possible link to anaemia being a significant predictor may have been found in this study however adequate data was not provided to allow the reader to evaluate this. Overall their findings are unlikely to change current practice but do highlight the need for careful postoperative planning in at risk groups.
Summary by Dr Rachael Owen