Respiratory Compromise After Anterior Cervical Spine Surgery: Incidence, Subsequent Complications, and Independent Predictors

Abstract

Study design: Retrospective cohort study. Objective: Respiratory compromise (RC) is a rare but catastrophic complication of anterior cervical spine surgery (ACSS) commonly due to compressive fluid collections or generalized soft tissue swelling in the cervical spine. Established risk factors include operative duration, size of surgical exposure, myelopathy, among others. The purpose of this current study is to identify the incidence and clinical course of patients who develop RC, and identify independent predictors of RC in patients undergoing ACSS for cervical spondylosis. Methods: A large, prospectively-collected registry was used to identify patients undergoing ACSS for spondylosis. Patients with posterior cervical procedures were excluded. Baseline patient characteristics were compared using bivariate analysis, and multivariate analysis was employed to compare postoperative complications and identify independent predictors of RC. Results: 298 of 52,270 patients developed RC (incidence 0.57%). Patients who developed RC had high rates of 30-day mortality (11.7%) and morbidity (75.8%), with unplanned reoperation and pneumonia the most common. The most common reason for reoperations were hematoma evacuation and tracheostomy. Independent patient-specific factors predictive of RC included increasing patient age, male gender, comorbidities such as chronic cardiac and respiratory disease, preoperative myelopathy, prolonged operative duration, and 2-level ACCFs. Conclusion: This is among the largest cohorts of patients to develop RC after ACSS identified to-date and validates a range of independent predictors, many previously only described in case reports. These results are useful for taking preventive measures, identifying high risk patients for preoperative risk stratification, and for surgical co-management discussions with the anesthesiology team.

Airway Complications After Anterior Cervical Spine Surgery: Etiology and Risk Factors

“…6 Since then, two large database studies have reported the incidence and predictors of airway or respiratory complications specific to ACSS, but none have discussed the etiology or management of patients presenting with these complications. 2,4 The two most common causes of airway compromise after ACSS are hematoma and soft tissue edema. Postoperative hematomas are hypothesized to occur secondary to iatrogenic vascular injury during surgery or excessive intramuscular bleeding, without adequate hemostasis.…”

“…34 A complete list of the medical comorbidities that increase the risk of airway complications following ACSS is presented in Table 2. Although several studies have found hypertension to be a significant risk factor and even predictor for respiratory compromise on multi-variate regression, 4,11 none have given an explanation as to the mechanism behind these finding use. Although not included in the table, perioperative anticoagulant was found to be a risk factor for postoperative hematoma and unplanned reintubation in a study evaluating three observational data sets.…”

“…13 In contrast, male sex has been found to be a risk factor for both pharyngeal and laryngeal airway soft tissue swelling 11 as well as unplanned intubation and ventilator requirement after ACSS in several other studies. 2,4,32,33 Medical Comorbidities. DePasse et al evaluated the risk factors of airway complications in patients undergoing osteotomies for cervical spine deformity surgery using the NSQIP database.…”

“…2 Boddapati et al evaluated a larger cohort from the same registry over a longer period and found that dependent functional status was a significant risk factor for respiratory compromise after ACSS (OR 4.4). 4 Finally, Burton et al found preoperative functional dependent status to be a good marker for unplanned postoperative intubation after elective ACSS 7 Trauma. Patients with cervical trauma present additional challenges in airway management.…”

“…Airway complications are those causing obstruction requiring prolonged or unplanned respiratory support. These occur with a reported incidence of 0.57-6.1% after ACSS, [1][2][3][4] of which approximately onethird result in postoperative reintubation. 5 The rate of postoperative prolonged ventilatory support has also been reported to be as high as 0.6% for single-level to 1.9% for multilevel cervical surgeries 3,6 and is associated with a 2.5to 4-fold increase in mortality.…”