Cervical spine injury from trauma can lead to a devastating spinal cord injury (SCI). Blunt trauma accounts for 2-5% of cervical spine injury.¹ We present the management of a patient with cervical spine injury, highlighting the challenges encountered in airway control, hemodynamic stability, extubation planning, and postoperative pain management. These challenges will be further discussed in the context of current evidence, with emphasis on the rationale guiding each clinical decision.

Case Description

A 65-year-old male with a past medical history of coronary artery disease and hypertension presents after a motor vehicle accident. He complained of severe neck pain, bilateral arm numbness and weakness, and right-sided chest pain. Imaging revealed that it has C3-C4, C4-C5 cervical vertebral spine injury. The patient was placed in a cervical collar and scheduled for emergency cervical spine decompression and fusion from C2-C6 with intraoperative neuromonitoring.

The anesthesia plan was discussed with the patient, including the preference for awake fiberoptic intubation and placement of an arterial line. However, the patient expressed discomfort with the idea of being intubated while awake and requested to be anesthetized prior to intubation. The resident prepared the fiberoptic bronchoscope tower and kept a Glidescope on standby.

After placement of the arterial line, general anesthesia was induced with fentanyl and propofol, and succinylcholine was administered to facilitate intubation. Two attempts at fiberoptic intubation failed, and the patient’s oxygen saturation began to drop. Ventilation with 100% oxygen restored oxygenation. Intubation was ultimately achieved using a Glidescope. Following intubation, a second peripheral intravenous line was placed, and the neurophysiology team obtained baseline evoked potentials. However, the patient’s blood pressure (BP) began to drop, and fluid boluses and phenylephrine provided only temporary improvement. After stabilization of BP and positioning the patient prone, surgery proceeded and lasted approximately five hours, with an estimated blood loss of 250 mL and administration of 3 L of crystalloid. An intersemispinalis nerve block was performed at the end of the procedure to facilitate postoperative pain control, and the patient was extubated. After extubation, he developed labored breathing and a decrease in oxygen saturation. Reintubation was required after several attempts using a Glidescope. The patient was transferred to the intensive care unit (ICU), where he continued postoperative care and was successfully extubated the next day.

Main points of discussion:

• New Intubation Guidelines
• Hemodynamic monitoring and management
• To extubate or not to extubate?
• Intersemispinalis nerve block as part of the multimodal pain management

Airway management in patients with cervical spine injury

The best method of tracheal intubation in patients with cervical spine injury is still controversial. Clinicians are often concerned that airway management may exacerbate an existing neurological deficit or cause a new SCI. A postoperative neurological complication rate of 0.34% was reported in a meta-analysis including 1177 patients with cervical SCI who underwent surgical fixation. ²

Impact of airway and intubation maneuvers on cervical spine movement

A study in healthy patients showed that two-handed jaw thrust resulted in no significant change in anterior movement and small changes in intervertebral angulation of about 3° at Occiput–C4. In comparison to jaw thrust, head tilt with chin lift resulted in significantly more flexion-extension, axial rotation, and lateral bending.

When cricoid pressure was applied, the most significant angular motion was 3° at C5-C6. The most significant linear displacement was 1.36 mm, also at C5-C6. Updated guidelines recommend that, if cricoid pressure is needed, it should be carried out by the most experienced and trained provider and should be avoided if there is evidence of laryngeal injury or if it impedes intubation.³

Intubation

With direct laryngoscopy (DL), most cervical motion is produced at the occipito-atlantal and atlantoaxial joints. The sub-axial cervical segments (C2-C5) are displaced only minimally.⁴ The mean motion at the C1/C2 level was 10.2 ± 7.3°, 5.0 ± 6.3°, 1.6 ± 3.2 for DL, Intubating laryngeal mask airway, and fiberoptic bronchoscopy (FOB), respectively.⁴  DL also decreases the width of dural sac significantly when compared to video laryngoscopy in cadaveric models with atlanto-occipital instability.⁵ In addition, when DL is used on the immobilized spine, the average failure rate on the first attempt is > 20%.

Awake fiberoptic tracheal intubation

Although awake fiberoptic bronchoscope (FOB) intubation has historically been considered the gold standard for patients with cervical spine injury, there is limited evidence to support this assumption. In the trauma setting, the overall success rate of FOB intubation has been reported as 83.3%.⁶ When somatosensory evoked potential (SSEP) signals were compared during intubation with video laryngoscopy versus FOB, no significant differences in SSEP changes were observed between the two groups. However, first-pass intubation success was higher with video laryngoscopy. Ultimately, all patients in both groups were successfully intubated. Notably, 13 patients experienced SSEP changes after positioning, but none developed postoperative neurological deficits.⁷

Expert multidisciplinary, multi-society recommendations were published in 2024 regarding intubation in patients with cervical spine trauma as follows: ⁸

• Attempts should be made to minimize cervical spine movement during pre-oxygenation and facemask ventilation.
• When a simple maneuver is required to maintain an airway, the jaw thrust technique should be used rather than the head tilt plus chin lift method.
• Clinicians should use supraglottic airway devices with which they are familiar and that are available to them.
• Whenever possible, video laryngoscopy should be used for tracheal intubation.
• Consider using an adjunct such as a stylet or bougie when performing tracheal intubation in a patient whose cervical spine is immobilized.
• During tracheal intubation attempts, the anterior portion of a rigid cervical collar should be removed, as this both minimizes cervical spine movement and improves the laryngoscopist’s view.

Hemodynamic Management and Treatment

SCI causes profound deficits of motor, sensory, and autonomic functions in patients. The goal of acute SCI management is to reduce secondary injuries and improve neurological recovery after its occurrence.

Mean Arterial Pressure (MAP)

The American Association of Neurological Surgeons/Congress of Neurological Surgeons 2013 ⁹ SCI guideline recommends raising the mean arterial pressure (MAP) between 85 and 90 mmHg for the first 7 days following an acute SCI, using the Association Improvement Scale, showed neurological improvement in patients where the MAP was maintained above 85mmHg for 7 days. Vasoactive agents such as vasopressin, phenylephrine, and norepinephrine are commonly used to achieve the desired MAP. ¹⁰

Spinal Cord Perfusion Pressure

Spinal Cord Perfusion Pressure (SCPP) is important to control in patients with SCI. Squair et al ¹¹ demonstrated that maintaining SCPP above 50 mmHg is a strong predictor for neurologic recovery after SCI. The author argued that SCPP could provide a guideline for useful information on hemodynamic management in patients with acute SCI. Streijger et al.¹² showed that norepinephrine and phenylephrine are effective in improving spinal cord blood flow (SCBF) and oxygenation; however, after cord decompression, norepinephrine showed a higher SCBF and PaO₂ increase than phenylephrine. Additionally, norepinephrine was found to be a better vasopressor than dopamine to maintain elevated MAP. Complications associated with the use of vasopressors should be taken into consideration when they are used to maintain MAP and SCPP.

To extubate or not to extubate?

Airway complications following posterior cervical spine fusion are found in 1.2-27% of patients, some requiring reintubation or delayed extubation. Predictors of reintubation include the number of vertebral levels fused (more than 4-6), operative time exceeding four hours, higher fusion of C2-C4, higher total crystalloid and blood administered, older age, higher ASA class, and a history of difficult intubation. Delayed extubation, on the other hand, results in higher postoperative pneumonia and a longer duration of ICU stay.¹³

Postoperative pain control- Inter-semispinalis Plane Block

Cervical spinal fusion is one of the most painful surgeries.¹⁴ Postoperative pain management is crucial for improving patient recovery and overall outcomes. A multimodal approach is usually recommended; however, it is still heavily dependent on opioids. The intersemispinalis plane block (ISPB) was recently described as a component of multimodal analgesia to help reduce opioid requirements.

It involves injecting a local anesthetic into the fascial plane between the semispinalis capitis and semispinalis cervicis muscles, targeting the dorsal rami of the cervical spinal nerves. This method was found to reduce postoperative pain and reduce the intraoperative and postoperative opioid consumption. The evidence is still limited but is evolving. ^15,16 More studies are needed to judge the newly developed promising nerve block.

Figure 1 : Anatomy of Intersemispinalis Block

References

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