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

Action protocol of medical staff for airway obstruction after anterior cervical spine surgery: A systematic review of case reports

BACKGROUND

Postoperative airway obstruction after anterior cervical spine surgery (ACSS) can be a fatal complication. Occasionally, it rapidly progresses to complete obstruction. There are no established standardized protocols on how medical staff should assess for signs and symptoms, seek help, or facilitate airway management after ACSS to prevent unfavorable events. This study aimed to primarily describe a systematic approach by assessing the signs and treatment outcomes of airway compromise in patients who underwent ACSS. Further, it recommended an action protocol after extubation for medical staff according to patients' symptoms to prevent unfavorable outcomes.

METHODS

An extensive literature search was performed on PubMed, Web of Science, and the Cochrane Library to identify case reports, case series, and cohort studies restricted to English and published between January 1990 and March 2023. We included cases that described the signs, symptoms, and treatment of airway obstruction after ACSS. Meanwhile, cases involving complications of other known causes, cases of trauma or occipital-cervical fixation, or those using bone morphogenetic protein were excluded.

RESULTS

Twenty cases from 17 studies were obtained, and their study quality was acceptable. Four patients died, and two presented with hypoxic ischemic encephalopathy. Further, five of six patients had fatal complications that initially developed within 7 h after surgery. Then, 9 (69%) of 13 patients with evidence of hematoma (69%) showed initial symptoms within 12 h after surgery. Finally, 9 of 11 patients with early-stage symptoms had favorable outcomes, and patients who developed late-stage symptoms commonly had unfavorable outcomes.

CONCLUSION

The early identification of signs and symptoms and immediate treatment are important, particularly within 12 h postoperatively. We suggest a novel action protocol for medical staff according to symptom urgency, which includes the measurement of neck circumference using a string for evaluating neck swelling.

Subclinical respiratory dysfunction and impaired ventilatory adaptation in degenerative cervical myelopathy

Degenerative cervical myelopathy (DCM) is a debilitating neurological condition characterized by chronic compression of the cervical spinal cord leading to impaired upper and lower limb function. Despite damage to areas of the cervical spinal cord that house the respiratory network, respiratory dysfunction is not a common symptom of DCM. However, DCM may be associated with respiratory dysfunction, and this can affect the ventilatory response to respiratory challenges during emergence from anesthesia, exercise, or pulmonary disease. Surgical spinal cord decompression, which is the primary treatment for DCM, leads to improved sensorimotor function in DCM; yet its impact on respiratory function is unknown. Here, using a clinically relevant model of DCM, we evaluate respiratory function during disease progression and assess adaptive ventilation to hypercapnic challenge before and after surgical intervention. We show that despite significant and progressive forelimb and locomotor deficits, there was no significant decline in eupneic ventilation from the early to late phases of spinal cord compression. Additionally, for the first time, we demonstrate that despite normal ventilation under resting conditions, DCM impairs acute adaptive ventilatory ability in response to hypercapnia. Remarkably, akin to DCM patients, surgical decompression treatment improved sensorimotor function in a subset of mice. In contrast, none of the mice that underwent surgical decompression recovered their ability to respond to hypercapnic ventilatory challenge. These findings underscore the impact of chronic spinal cord compression on respiratory function, highlighting the challenges associated with ventilatory response to respiratory challenges in individuals with DCM. This research highlights the impact of cervical spinal cord compression on respiratory dysfunction in DCM, as well as the persistence of adaptive ventilatory dysfunction after surgical spinal cord decompression. These results indicate the need for additional interventions to enhance recovery of respiratory function after surgery for DCM.

Risk Factors for Reintubation After Anterior Cervical Spine Surgery: Comparative Study of Patients With Cervical Spine Trauma and Patients With Cervical Degenerative Disease

STUDY DESIGN

Single-center retrospective study.

OBJECTIVES

The aim was to compare the postoperative outcomes of anterior cervical spine surgery (ACSS) in patients with and without cervical spine trauma.

SUMMARY OF BACKGROUND

Few papers have addressed airway obstruction after anterior ACSS for patients with cervical spine trauma. This study aimed to compare airway obstruction after ACSS between patients with cervical degenerative disorders and cervical spine injuries and identify the risk factors for unplanned postoperative reintubation.

MATERIALS AND METHODS

Seventy-seven patients who underwent ACSS were enrolled in this retrospective study. There were 52 men and 25 women, with a mean age of 60.3±15.5 years old. The causes of surgery were as follows: 24 cervical spine fractures or dislocations, 12 spinal cord injuries without bony fracture, 19 disc herniations, and 22 myelopathies. The patients' characteristics, operative data, and risk factors for unplanned reintubation within 5 days postoperatively were analyzed using medical records.

RESULTS

Postoperative reintubation was performed in 3 patients (3.9%), all of whom suffered trauma. We further examined risk factors for reintubation in patients in the trauma group. There was no significant difference between the reintubation (R) and nonreintubation (non-R) groups in age, sex, body mass index, amount of blood loss and operation time, preoperative paralysis severity, and the number of fused segments. Patients in group R had significantly higher rates of severe anterior element injury (100% vs. 27.3%, P=0.0011). Airway obstruction due to laryngopharyngeal edema and swelling was confirmed by laryngoscopy and computed tomography images.

CONCLUSIONS

Unplanned reintubation after ACSS occurred at a higher rate in trauma patients than in patients with degenerative disorders. Our results suggested that the severe damage to the anterior element of the cervical spine was associated with postoperative reintubation.

EVIDENCE LEVEL

Level IV.

Impact of delay extubation on the reintubation rate in patients after cervical spine surgery: a retrospective cohort study

BACKGROUND

The incidence of cervical airway obstruction after cervical spine surgery (CSS) ranges from 1.2 to 14%, and some require reintubation. If not addressed promptly, the consequences can be fatal. This study investigated delayed extubation's effect on patients' reintubation rate after cervical spine surgery.

METHODS

We performed a retrospective case-control analysis of cervical spine surgery from our ICU from January 2021 to October 2022. Demographic and preoperative characteristics, intraoperative data, and postoperative clinical outcomes were collected for all 94 patients. Univariable analysis and multivariable logistic regression were used to analyze postoperative unsuccessful extubation risk factors following cervical spine surgery.

RESULTS

The patients in the early extubation (n = 73) and delayed extubation (n = 21) groups had similar demographic characteristics. No significant differences were found in the reintubation rate (0 vs. 6.8%, p = 0.584). However, the delayed extubation group had significantly more patients with 4 and more cervical fusion segments (42.9 vs. 15.1%, p = 0.013),more patients with an operative time greater than 4 h (33.3 vs. 6.8%, p = 0.004)and all patients involved C2-4 (78 vs. 100%, p = 0.019).Also, patients in the delayed extubation group had a longer duration of ICU stay (152.9 ± 197.1 h vs. 27.2 ± 45.4 h, p < 0.001) and longer duration of hospital stay (15.2 ± 6.9 days vs. 11.6 ± 4.1 days, p = 0.003). Univariate and multivariate analysis identified the presences of cervical spondylotic myelopathy (CSM) (OR 0.02, 95% CI 0-0.39, p = 0.009) and respiratory diseases (OR: 23.2, 95% CI 2.35-229.51, p = 0.007) as unfavorable prognostic factor for reintubation.

CONCLUSIONS

Our analysis of patients with cervical spondylosis who received CSS indicated that delayed extubation was associated with the presence of respiratory diseases and CSM, longer operative time, more cervical fusion segments, and longer duration of ICU and hospital stays.

Comorbidity data collection across different spine registries: an evidence map

INTRODUCTION

Comorbidities are significant patient factors that contribute to outcomes after surgery. There is highly variable collection of this information across the literature. To help guide the systematic collection of best practice data, the Australian Spine Registry conducted an evidence map to investigate (i) what comorbidities are collected by spine registries, (ii) how they are collected and (iii) the compliance and completeness in collecting comorbidity data.

METHOD

A literature search was performed to identify published studies of adult spine registry data reporting comorbidities. In addition, targeted questionnaires were sent to existing global spine registries to identify the maximum number of relevant results to build the evidence map.

RESULTS

Thirty-six full-text studies met the inclusion criteria. There was substantial variation in the reporting of comorbidity data; 55% of studies reported comorbidity collection, but only 25% reported the data collection method and 20% reported use of a comorbidity index. The variation in the literature was confirmed with responses from 50% of the invited registries (7/14). Of seven, three use a recognised comorbidity index and the extent and methods of comorbidity collection varied by registry.

CONCLUSION

This evidence map identified variations in the methodology, data points and reporting of comorbidity collection in studies using spine registry data, with no consistent approach. A standardised set of comorbidities and data collection methods would encourage collaboration and data comparisons between patient cohorts and could facilitate improved patient outcomes following spine surgery by allowing data comparisons and predictive modelling of risk factors.