P33. Incidence, risk factors and clinical outcomes of cervical hematoma: an analysis from the Michigan Spine Surgery Improvement Collaborative registry

Abstract

<h3>BACKGROUND CONTEXT</h3> Postoperative hematoma following anterior cervical spine surgery is an uncommon but potentially fatal complication. Persistent bleeding resulting in significant hematoma displaces the larynx and trachea resulting in swallowing difficulties or airway obstruction. Due to its low incidence, risk factors and clinical outcomes data are limited. From a large database, the authors sought to identify some common characteristics in patients who developed hematoma and evaluate their clinical outcomes after undergoing anterior cervical spine surgery. <h3>PURPOSE</h3> From a large database, the authors sought to identify some common characteristics in patients who developed hematoma and evaluate their clinical outcomes after undergoing anterior cervical spine surgery. <h3>STUDY DESIGN/SETTING</h3> Ambispective (retrospective/prospective)/Multicenter collaborative. <h3>PATIENT SAMPLE</h3> Patients undergoing anterior cervical spine surgery. <h3>OUTCOME MEASURES</h3> Hematoma incidence, PROMIS-PF score, other postoperative complications. <h3>METHODS</h3> The Michigan Spine Surgery Improvement Collaborative (MSSIC) is a statewide quality improvement initiative. Anterior cervical cases in MSSIC registry from 2014-2018 were identified and divided into two groups: Nonhematoma or Hematoma. Chi-square and t-test analyses were done to compare the two groups in terms of demographics, surgical characteristics, patient reported outcomes (baseline and postoperative PROMIS-PF score) and other postoperative symptoms or complications. All analyses were performed by using SAS 9.4. <h3>RESULTS</h3> Of the 9,958 cases, postoperative hematoma occurred in 114 (1.1%). Hematoma was associated with male gender (1.6% vs 0.7%, p .10 for all). A greater percentage of patients in the hematoma group reported dysphagia (6.9% vs 29.8%, p .05). <h3>CONCLUSIONS</h3> Postoperative hematoma after anterior cervical surgery was rare (1.1%). It was associated with male gender, increasing age, preoperative anticoagulation, prior spine surgery, inpatient procedures and surgeries involving C3-C5 and C3-C6. Hematoma was significantly associated with the adverse outcomes of dysphagia, prolonged hoarseness, and weakness - though PROMIS scores showed no difference at follow-up. Hematoma after anterior cervical surgery is rare but a serious complication. Our large database review revealed several interesting risk factors associated with hematoma. Procedures involving C3-C5 and C3-C6 had the highest rate of hematoma compared to more caudal surgeries. Difficulties with exposure as well as vascular anatomy in the upper cervical spine, the cricothyroid arteries bilaterally, could explain this finding. Thorough visual inspection to ensure hemostasis is obtained prior to closure is essential. Hematoma, if left unrecognized, can swiftly develop, and put patients at significant risk for life threatening airway obstruction or great vessel compression. <h3>FDA DEVICE/DRUG STATUS</h3> This abstract does not discuss or include any applicable devices or drugs.