Prevalence and Outcomes in Patients Undergoing Reintubation After Anterior Cervical Spine Surgery: Results From the AOSpine North America Multicenter Study on 8887 Patients

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.

Postoperative Airway Management after Anterior Cervical Spine Surgery: Retrospective Neurosurgical Multicenter Study

Airway complications that occur after anterior cervical spine surgery pose a life-threatening risk, which encompasses complications including prolonged intubation, unplanned reintubation, and/or necessity of tracheostomy. The present study aimed to identify the surgical risks associated with postoperative airway complications in neurosurgical training institutes. A retrospective, multicenter, observational review of data from 365 patients, who underwent anterior cervical spine surgery between 2018 and 2022, at three such institutes was carried out. Postoperative airway complication was defined as either the need for prolonged intubation on the day of surgery or the need for unplanned reintubation. The perioperative medical information was obtained from their medical records. The average age of the cohort was over 60 years, with males comprising approximately 70%. Almost all surgeries predominantly involved anterior cervical discectomy and fusion or anterior cervical corpectomy and fusion, with most surgeries occurring at the level of C5/6. In total, 363 of 365 patients (99.5%) were extubated immediately after surgery, and the remaining two patients were kept under intubation because of the risk of airway complications. Of the 363 patients who underwent extubation immediately after surgery, two (0.55%) required reintubation because of postoperative airway complications. Patients who experienced airway complications were notably older and exhibited a significantly lower body mass index. The results of this study suggested that older and frailer individuals are at an elevated risk for postoperative airway complications, with immediate postoperative extubation generally being safe but requiring careful judgment in specific cases.

The Postoperative Airway Compromise Score-First Steps to Developing a Postoperative Tool for the Assessment of Upper Airway-Related Complications Following Anterior Cervical Spine Surgery

BACKGROUND

Acute upper airway compromise is a rare but catastrophic complication after anterior cervical discectomy and fusion. This study aims to develop a score to identify patients at risk of acute postoperative airway compromise (PAC).

METHODS

Potential risk factors for acute PAC were selected by a modified Delphi process. Ten patients with acute PAC were identified of 1466 patients who underwent elective anterior cervical discectomy and fusion between July 2014 and May 2019. A comparison group was created by a randomized selection process (non-PAC group). Factors associated with PAC and a P value of < 0.10 were entered into a logistic regression model and coefficients contributed to each risk factor's overall score. Calibration of the model was evaluated using the Hosmer-Lemeshow goodness-of-fit test. Quantitative discrimination was calculated, and the final model was internally validated with bootstrap sampling.

RESULTS

We identified 18 potential risk factors from our Delphi process, of which 6 factors demonstrated a significant association with airway compromise: age >65 years, current smoking status, American Society of Anesthesiologists class >2, history of a bleeding disorder, surgery of upper subaxial cervical spine (above C4), and duration of surgery >179 minutes. The final prediction model included 5 predictors with very strong performance characteristics. These 5 factors formed the PAC score, with a range from 0 to 100. A score of 20 yielded the greatest balance of sensitivity (80%) and specificity (88%).

CONCLUSIONS

The acute PAC score demonstrates strong performance characteristics. The PAC score might help identify patients at risk of upper airway compromise caused by surgical site abnormalities.

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.

Variation in Prevertebral Soft Tissue Swelling after Staged Combined Multilevel Anterior-Posterior Complex Cervical Spine Surgery: Anterior Then Posterior (AP) versus Posterior Then Anterior-Posterior (PAP) Surgery

The influence of the sequence of surgery in the development of prevertebral soft tissue swelling (PSTS) in staged combined multilevel anterior-posterior complex spine surgery was examined. This study was conducted as a retrospective study of patients who underwent staged combined multilevel anterior-posterior complex cervical spine surgery from March 2014 to February 2021. Eighty-two patients were identified, of which fifty-seven were included in the final analysis after screening. PSTS was measured from routine serial monitoring lateral cervical radiographs prior to and after surgery for five consecutive days at each cervical level from C2 to C7 in patients who underwent anterior then posterior (AP) and posterior then anterior-posterior (PAP) surgery. The mean PSTS measurements significantly differed from the preoperative to postoperative monitoring days at all cervical levels (p = 0.0000) using repeated measures analysis of variance in both groups. PSTS was significantly greater in PAP than in AP at level C2 on postoperative day (POD) 1 (p = 0.0001). PSTS was more prominent at levels C2-4 during PODs 2-4 for both groups. In staged combined multilevel anterior-posterior complex spine surgery, PSTS is an inevitable complication. Therefore, surgeons should monitor PSTS after surgery when performing anterior-posterior complex cervical spine surgery, especially in the immediate postoperative period after PAP surgery.

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

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.

The Role of Nutrition in Degenerative Cervical Myelopathy: A Systematic Review

Introduction

Degenerative cervical myelopathy (DCM) is the commonest cause of adult spinal cord impairment worldwide, encompassing chronic compression of the spinal cord, neurological disability and diminished quality of life. Evidence on the contribution of environmental factors is sparse; in particular, the role of nutrition in DCM is unknown. The objective of this review was to assess the effect of nutrition on DCM susceptibility, severity and surgical outcome.

Methods

A systematic review in MEDLINE and Embase was conducted following PRISMA guidelines. Full-text papers in English papers, focussing on cervical myelopathy and nutrition, published before January 2020 were considered eligible. Quality assessments were performed using the GRADE assessment tool. Patient demographics, nutritional factor and DCM outcomes measures were recorded. Relationships between nutritional factors, interventions and disease prognosis were assessed.

Results

In total, 5835 papers were identified of which 44 were included in the final analysis. DCM patients with pathological weight pre-operatively were more likely to see poorer improvements post-surgically. These patients experienced poorer physical and mental health improvements from surgery compared to normal weight patients and were more likely to suffer from post-operative complications such as infection, DVT, PE and hospital readmissions. Two trials reporting benefits of nutritional supplements were identified, with 1 suggesting Cerebrolysin to be significant in functional improvement. An unbalanced diet, history of alcohol abuse and malnourishment were associated with poorer post-operative outcome.

Conclusion

Although the overall strength of recommendation is low, current evidence suggests nutrition may have a significant role in optimising surgical outcome in DCM patients. Although it may have a role in onset and severity of DCM, this is a preliminary suggestion. Further work needs to be done on how nutrition is defined and measured, however, the beneficial results from studies with nutritional interventions suggest nutrition could be a treatment target in DCM.

A Detailed Clinical Course Leading to Hypoxic Ischemic Encephalopathy After Anterior Cervical Spine Surgery: A Case Report

CASE

A 48-year-old woman underwent anterior cervical discectomy and fusion at C5/6. Extubation was performed immediately after surgery. Tachycardia, limb tremor, and panic attack developed approximately 4 hours after surgery at 16:15. Thirty minutes later, cessation of respiration occurred at 16:50. An experienced anesthesiologist attempted intubation but was unsuccessful because of laryngopharyngeal edema at the C2 level. Finally, an otolaryngologist performed tracheotomy and secured the airway at 17:20 but hypoxic encephalopathy ensued.

CONCLUSION

Predicting the airway obstruction caused by laryngopharyngeal edema was very difficult; hence, to prevent critical complications, systematic perioperative management is essential in anterior cervical spine surgery.

Risk Factors and Assessment Using an Endoscopic Scoring System for Postoperative Respiratory Complications after Anterior Cervical Decompression and Fusion Surgery

Introduction

Postoperative respiratory complications (PRC) are one of the most serious complications. Potentially life-threatening accidents can occur after an anterior cervical discectomy and fusion (ADF), such as airway obstruction and aspiration pneumonia. Despite numerous studies, preoperative predictive and preventive methodology has yet to be established.

As reported in our previous study, the evaluation of preoperative dysphagia using the eating assessment tool (EAT-10) and a flexible endoscopic evaluation of swallowing (FEES) is useful for predicting the incidence and risk factors of dysphagia after ADF.

Methods

This prospective study comprised 60 consecutive patients who underwent ADF. An otolaryngologist and a speech-language-hearing therapist preoperatively and 1 week postoperatively evaluated dysphagia using EAT-10 and Hyodo-Komagane (H-K) scores during FEES. Patient demographics, comorbidities, and pre- and postoperative dysphagia were compared between patients with and without PRC.

Results

Seven of 60 (11.6%) patients had preoperative dysphagia diagnosed using the H-K score. A significant positive correlation existed between the pre- and postoperative H-K scores. Of all 60 cases, eight (13.3%) had PRC. Among them, two required reintubation due to airway obstruction and six had aspiration pneumonia. The PRC(+) group was significantly older and more prone to diabetes and asthma. The preoperative H-K score of the PRC(+) group was significantly higher than that of the PRC(−) group. Postoperatively, but not preoperatively, EAT-10 was significantly higher in the PRC(+) group.

Conclusions

Preoperative dysphagia may potentially exacerbate postoperative dysphagia after ADF. A preoperative evaluation of dysphagia using the H-K score during FEES is a useful method for predicting and reducing the risk of PRC.

Level of Evidence: 3

Failure to extubate and delayed reintubation in elective lumbar fusion: An analysis of 57,677 cases

OBJECTIVES

There is a scarcity of literature exploring the consequences of Failure To Extubate (FTE) and Delayed Reintubation (DRI) in spine surgery. While it is reasonable to believe that patients who FTE or undergo DRI after Posterior Lumbar Fusion (PLF) and Transforaminal Lumbar Interbody Fusion (TLIF) are at risk for graver outcomes, there is minimal data to explicitly support that. The goal of this study was to investigate the morbidity and mortality associated with FTE and DRI after lumbar spine surgery in a large pool of patients.

PATIENTS AND METHODS

We conducted a retrospective multicenter study of patients that underwent elective posterior lumbar fusion (PLF) and transforaminal lumbar interbody fusion (TLIF) using the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database from 2006 to 2016. We excluded patients with disseminated cancer, metastatic disease to the neural axis, patient with spinal epidural abscess, and patients with ventilator dependency prior to the operation.

RESULTS

57,677 patients from 2006 to 2016 were identified; 55 patients (0.1 %) had FTE and 262 patients (0.46 %) had DRI. The incidence of pneumonia was 27.2-fold greater in the FTE group and septic shock was 63.5-fold greater. All complications listed below are significance to p < 0.001. Deep vein thrombosis, pulmonary embolism, myocardial infarction and cardiac arrest were respectively, 10.4-, 12.2-, 22.8-, and 45.5- fold greater in the FTE group. Overall complication rate differed significantly between the two groups and were 9.8-fold greater in the FTE group. FTE was associated with increased, length of stay and all complications except DVT and pulmonary embolism. FTE was profoundly associated with severe complications (OR 13.0, 95 % CI 7.2-23.5) and mortality (OR = 21.5, CI = 7.5-61.0). The DRI group had a significantly higher morbidity (OR = 71.0, CI = 44.1-114.4), including overall complication (OR = 21.2, CI = 16.0-28.0) and severe complications (OR = 34.4, CI = 26.1-45.3). The DRI group had significantly higher rates of pneumonia (OR = 37.0), DVT (OR = 9.6) and pulmonary embolism (OR = 7.0), septic shock (OR = 60.5), myocardial infarction (OR = 32.1,) and cardiac arrest (OR = 236.4).

CONCLUSION

FTE and DRI were highly predictive of morbidity and mortality. Overall, investigations of the effects of FTE and DRI following spine procedures are lacking. This large multi-center national database review is one of the first to provide insight into the consequences of FTE and DRI in lumbar fusion cases. Future investigation into the consequences and predictors of FTE and DRI in spine surgery are required.

Acute post-operative airway complications following anterior cervical spine surgery and the role for cricothyrotomy

Anterior cervical spine surgery (ACSS) is a common procedure, but not without its own risks and complications. Complications that can cause airway compromise occur infrequently, but can rapidly lead to respiratory arrest, leading to severe morbidity or death. Knowing emergent post-operative airway management including surgical airway placement is critical. We aim to review the different etiologies of post-operative airway compromise following ACSS, the predictable timeline in which they occur, and the most appropriate treatment and management for each. We place special emphasis on the timing and proper surgical technique for an emergent cricothyrotomy. Angioedema is seen the earliest as a cause of post-operative airway compromise, typically within 6-12 hours. Retropharyngeal hematomas can be seen between 6-24 hours, most commonly within 12 hours. Pharyngolaryngeal edema is seen within 24-72 hours. After 72 hours, retropharyngeal abscess is the most likely etiology. Several studies have utilized delayed extubation protocols following ACSS based on patient risk factors and found reduced postoperative airway complications and reintubation rates. The administration of perioperative corticosteroids continues to be controversial with high-level studies recommending both for and against their use. Animal studies showed that after cardiac arrest, the brain can recover if oxygenation is restored within 5 minutes, but this time is likely shorter with asphyxia prior to cardiac arrest. Experience and training are essential to reduce the time for successful cricothyrotomy placement. Physicians must be prepared to diagnose and treat acute postoperative airway complications following ACSS to prevent anoxic brain injury or death. If emergent intubation cannot be accomplished on the first attempt, physicians should not delay placement of a surgical airway such as cricothyrotomy.

Risk factors for 30-day outcomes in elective anterior versus posterior cervical fusion: A matched cohort analysis

OBJECTIVE

Cervical spine fusion is the preferred treatment modality for a variety of degenerative and/or myelopathic disorders. Surgeons select between two approaches (anterior or posterior cervical fusion [ACF; PCF]) based on pathoanatomical features and spinal levels involved. Complications and outcome profiles between the approaches following elective surgery have not been systematically investigated.

METHODS

Adult patients undergoing elective ACF or PCF were extracted from the American College of Surgeons National Surgical Quality Improvement Program years 2011-2014. Five hundred twenty-eight patients (264 ACF and 264 PCF) were matched 1:1 by age, sex, functional status, vertebral levels operated, and the American Society of Anesthesiologists classification. Multivariable regression was performed by surgical approach for operation time, complications, hospital length of stay (HLOS), and discharge destination, controlling for body mass index and comorbidities. Mean differences (B), odds ratios (ORs), and 95% confidence intervals (CIs) are reported.

RESULTS

Compared to ACF, PCF was associated with increased odds of blood transfusions >1 unit (OR = 4.31, 95% CI [1.18-15.75]; P = 0.027) and failure to discharge to home (OR = 3.68 [2.17-6.25]; P < 0.001), and increased mean HLOS (B = 1.72 days [1.19-2.26]; P < 0.001). No differences in operation time, other complications, or reoperation rates were found by surgical approach.

CONCLUSIONS

In a matched cohort analysis by age, sex, functional and physical status, and vertebral levels, elective PCF is associated with increased HLOS and increased likelihood of failing to discharge to home compared to ACF without increased risk of 30-day complications. Increased blood transfusion volume is noted for patients undergoing PCF. Future prospective studies are warranted.