Anesthetic implications of chronic disease of the cervical spine

Study comparing different airway assessment tests in predicting difficult laryngoscopy: A prospective study in geriatric patients

Background and Aims

Limited studies are available comparing diagnostic accuracy of various airway predictors in geriatric patients. We conducted this study with primary aim to evaluate and validate the predictive value of 'standard airway predictors' like modified Mallampati test, thyromental distance (TMD), sternomental distance, neck movement (NM), mouth opening (MO), dentition and 'new airway predictors' like upper lip bite test (ULBT), ratio of height to thyromental distance and thyromental height test (TMHT) for predicting difficult laryngoscopy in geriatric patients.

Methods

This prospective, observational study was conducted on 140 patients above 65 years of age of either sex, scheduled for elective surgery under general anaesthesia requiring endotracheal intubation. The age, weight, height, body mass index (BMI) and airway parameters were recorded. The laryngoscopic view was assessed by modified Cormack-Lehane scale. Standard formulae were used to calculate validity indexes.

Results

The incidence of difficult larygoscopy found in our study was 25%. The mean age of our study population was 69.37 ± 4.23 years. TMD exhibited the highest sensitivity (80%) and negative predictive value (NPV) (91.86%) as compared to other studied airway predictors. The positive predictive value (PPV) of ULBT was 100%. Moreover, ULBT exhibited highest accuracy (82.14%) and odds ratio (86.88) and high specificity (91.30%) for predicting difficult laryngoscopy in geriatric patients. NM and TMHT also exhibited high accuracy (77.85%, 77.14%) and PPV (59.09%, 52.94%).

Conclusions

TMD and ULBT both showed good predictive value in diagnosing difficult laryngoscopy in geriatric patients. Furthermore, NM and TMHT also exhibited higher diagnostic accuracy in predicting difficult airway in these patients.

A Retrospective Pilot Study for Preoperative Screening to Prevent Iatrogenic Cervical Spinal Cord Injury

PURPOSE

The preoperative medical clearance process is well established to screen for medical comorbidities and therefore must be thorough. However, screening for potential cervical spine disease is often overlooked. In older surgical candidates, the presence of cervical spondylosis can increase risk of iatrogenic cervical spine injury during prolonged neck extension in non-spinal surgeries. We present a standard protocol for cervical spine clearance and a novel sustained neck extension maneuver through a retrospective case series.

METHODS

Sixty-three consecutive cases that underwent preoperative cervical clearance between April 2012 and December 2019 were reviewed. Referral for clearance occurred through the department of anesthesiology after concerning radiographic or physical exam findings were noted. A standard preoperative screening protocol with a sustained one-minute neck extension maneuver was implemented. Recommendations were made for standard neck precautions with or without neuromonitoring or for cervical spine decompression surgery prior to the planned procedure.

RESULTS

There were 25 patients with symptoms of myelopathy, 11 with radiculopathy and 13 with neck pain at baseline. Cervical spondylosis was observed in 51 patients, cervical canal stenosis in 29 and cervical myelomalacia in six. Fifty-seven patients underwent neck extension exam and 25 exhibited new or worsening symptoms. Myelopathic symptoms and radicular pain at baseline and positive Hoffman's and Spurling's sign, independently, were significantly associated with a positive neck extension exam (p<0.05). Fourteen patients were recommended for cervical decompression prior to planned procedure.

CONCLUSIONS

Our preoperative cervical spine clearance protocol is safe and may aid in identifying patients susceptible to iatrogenic cervical spine injury.

Anatomic and physiopathologic changes affecting the airway of the elderly patient: implications for geriatric-focused airway management

There are many anatomical, physiopathological, and cognitive changes that occur in the elderly that affect different components of airway management: intubation, ventilation, oxygenation, and risk of aspiration. Anatomical changes occur in different areas of the airway from the oral cavity to the larynx. Common changes to the airway include tooth decay, oropharyngeal tumors, and significant decreases in neck range of motion. These changes may make intubation challenging by making it difficult to visualize the vocal cords and/or place the endotracheal tube. Also, some of these changes, including but not limited to, atrophy of the muscles around the lips and an edentulous mouth, affect bag mask ventilation due to a difficult face-mask seal. Physiopathologic changes may impact airway management as well. Common pulmonary issues in the elderly (eg, obstructive sleep apnea and COPD) increase the risk of an oxygen desaturation event, while gastrointestinal issues (eg, achalasia and gastroesophageal reflux disease) increase the risk of aspiration. Finally, cognitive changes (eg, dementia) not often seen as related to airway management may affect patient cooperation, especially if an awake intubation is required. Overall, degradation of the airway along with other physiopathologic and cognitive changes makes the elderly population more prone to complications related to airway management. When deciding which airway devices and techniques to use for intubation, the clinician should also consider the difficulty associated with ventilating the patient, the patient's risk of oxygen desaturation, and/or aspiration. For patients who may be difficult to bag mask ventilate or who have a risk of aspiration, a specialized supralaryngeal device may be preferable over bag mask for ventilation. Patients with tumors or decreased neck range of motion may require a device with more finesse and maneuverability, such as a flexible fiberoptic broncho-scope. Overall, geriatric-focused airway management is necessary to decrease complications in this patient population.

Anesthetic considerations in acute spinal cord trauma

Patients with actual or potential spinal cord injury (SCI) are frequently seen at adult trauma centers, and a large number of these patients require operative intervention. All polytrauma patients should be assumed to have an SCI until proven otherwise. Pre-hospital providers should take adequate measures to immobilize the spine for all trauma patients at the site of the accident. Stabilization of the spine facilitates the treatment of other major injuries both in and outside the hospital. The presiding goal of perioperative management is to prevent iatrogenic deterioration of existing injury and limit the development of secondary injury whilst providing overall organ support, which may be adversely affected by the injury. This review article explores the anesthetic implications of the patient with acute SCI. A comprehensive literature search of Medline, Embase, Cochrane database of systematic reviews, conference proceedings and internet sites for relevant literature was performed. Reference lists of relevant published articles were also examined. Searches were carried out in October 2010 and there were no restrictions by study design or country of origin. Publication date of included studies was limited to 1990–2010.

An unusual cause of difficult intubation in a patient with a large cervical anterior osteophyte: a case report

This report describes a case in which a large anterior osteophyte on the C2 and C3 vertebrae, due to ankylosing spondylitis, resulted in distortion of the anatomy of the upper airway and difficult intubation. Ankylosing spondylitis (AS) is a progressive inflammatory disease, characterized by stiffening of the joints and ligaments. Stiffness of the cervical spine, atlanto-occipital, temporomandibular and cricoarytenoid joints may cause difficult intubation (1). This report describes a case in which a large anterior osteophyte on the C2 and C3 vertebrae, associated with AS, resulted in distortion of the anatomy of the upper airway and difficult intubation.