BACKGROUND: Multilevel spinal decompressions and fusions often require long anesthetic and operative times, which may result in airway edema and prolonged postoperative intubation. Delayed extubation can lead to bronchopulmonary infections and other complications. This study analyzed which factors correlated with the decision to delay extubation after multilevel spine surgery. METHODS: We reviewed the records of 289 patients who underwent multilevel spine surgery lasting ≥8 hours in the prone position from 2006 to 2012. Variables hypothesized to affect the decision of the anesthesiologist to delay extubation at the end of the surgery were collected. These included preoperative factors (age, sex, ASA class, history of obstructive sleep apnea, BMI, previous spine surgery, current cervical surgery, anterior in addition to posterior spine surgery, emergency surgery) and intraoperative factors (difficult intubation, number of surgical levels, case time, estimated blood loss, fluid and blood administration, attending handoff and resident handoff, and case end time). We also compared the incidence of pulmonary postoperative complications between patients extubated at the end of the case to patients who had a delayed extubation. RESULTS: A total of 126 patients (44%) were kept intubated after multilevel spine surgery. Multiple linear regression analysis showed factors that correlated with prolonged intubation which included age, ASA class, procedure duration, extent of surgery, total crystalloid volume administered, total blood volume administered, and the case end time. Patients who had a delayed extubation had a 3-fold higher rate of postoperative pneumonia. CONCLUSIONS: Our study found that age, ASA class, procedure duration, extent of surgery, and total crystalloid and blood volume administered correlate with the decision to delay extubation in multilevel prone spine surgery. It also finds that the time the case ends is an independent variable that correlates with the decision not to extubate at the end of a long multilevel spinal surgery. The incidence of postoperative pneumonia is higher in patients who had a delayed extubation after surgery.