Neuroanesthesiology Update

Risk factors for post-operative respiratory failure among 94,621 neurosurgical patients from 2006 to 2013: a NSQIP analysis

INTRODUCTION

Post-operative respiratory failure can occur after neurosurgical operations. Identification of risk factors for respiratory failure after neurosurgery may help guide clinical decision-making, decrease length of stay, improve patient outcomes, and lower costs.

METHODS

We performed a search of the ACS-NSQIP database for all patients undergoing operations with a neurosurgeon from 2006 to 2013. We analyzed demographics, past medical history, and post-operative respiratory failure, defined as unplanned intubation and/or ventilator dependence for more than 48 h post-operatively.

RESULTS

Of 94,621 NSQIP-reported neurosurgical patients from 2006 to 2013, 2325 (2.5 %) developed post-operative respiratory failure. Of these patients, 1270 (54.6 %) were male, with an overall mean age of 60.59 years; 571 (24.56 %) were current smokers and 756 (32.52 %) were ventilator-dependent. Past medical history included dyspnea in 204 patients (8.8 %), COPD in 198 (8.5 %), and congestive heart failure in 66 (2.8 %). The rate of post-operative respiratory failure decreased from 4.1 % in 2006 to 2.1 % in 2013 (p < 0.001). Of the 2325 patients with respiratory failure, 1061 (45.6 %) underwent unplanned intubation post-operatively and 1900 (81.7 %) were ventilator-dependent for more than 48 h. The rate of both unplanned intubation (p < 0.001) and ventilator dependence (p < 0.001) decreased significantly from 2006 to 2013. Multivariate analysis demonstrated that significant risk factors for respiratory failure included inpatient status (p < 0.001, OR = 0.165), age (p < 0.001, OR = 1.014), diabetes (p = 0.001, OR = 1.489), functional dependence prior to surgery (p < 0.001, OR = 2.081), ventilator dependence (p < 0.001, OR = 10.304), hypertension requiring medication (p = 0.005, OR = 1.287), impaired sensorium (p < 0.001, OR = 2.054), CVA/stroke with or without neurological deficit (p < 0.001, OR = 2.662; p = 0.002, OR = 1.816), systemic sepsis (p < 0.001, OR = 1.916), prior operation within 30 days (p = 0.026, OR = 1.439), and operation type (cranial relative to spine, p < 0.001, OR = 4.344, Table 4).

CONCLUSIONS

Based on the NSQIP database, risk factors for respiratory failure after neurosurgery include pre-operative ventilator dependence, alcohol use, functional dependence prior to surgery, stroke, and recent operation. The overall rate of respiratory failure decreased from 4.1 % in 2006 to 2.1 % in 2013 according to these data.

Update on anesthesia for craniotomy

PURPOSE OF REVIEW

In this review, we present an update on the relationship between anesthesia and intraoperative hemodynamic complications, early postanesthesia recovery, postoperative pain and postoperative nausea and vomiting after craniotomy. We also review latest advances in education and research in neuroanesthesia for brain surgery.

RECENT FINDINGS

Insights from clinical reports published from January 2012 to April 2013 on anesthesia for craniotomy will be summarized. Recent findings address the need for a tight intraoperative hemodynamic monitoring - that should include aggressive prevention of arterial hypotension and cardiac arrhythmias - and a careful management of fluids and electrolytes balance. Data on the relationship between anesthesia (selection of anesthetics used intraoperatively) and early recovery demonstrate a limited benefit when ultra-short acting drugs (as remifentanil vs fentanyl) are used. Evidence on postoperative pain and postoperative nausea and vomiting contribute to define how to better prevent and treat these complications. Latest guidelines on training and research in neuroanesthesia define unique end points in this subspecialty.

SUMMARY

Neuroanesthesia for craniotomy should be aimed to ensure intraoperative loss of consciousness (unless awake craniotomy is the selected anesthesiological approach), pain control and an uneventful postoperative recovery, but should also be addressed to manipulate physiological variables including cerebral blood flow and to obtain optimal surgical exposure.