Mean Arterial Pressure Management in Spinal Cord Injury Patients Undergoing Cervical Spine Surgery
While there is insufficient high-quality evidence specifically for cervical spine surgery patients, maintaining a MAP > 85 mmHg for 5-7 days after spinal cord injury is suggested based on expert consensus to optimize neurological outcomes. 1
Current Evidence on MAP Targets
The American Association of Neurological Surgeons/Congress of Neurological Surgeons recommends targeting supra-physiological MAP > 85 mmHg within the first 5-7 days after spinal cord injury, though this recommendation is based on limited evidence 1
The 2019 Congress of Neurological Surgeons guidelines acknowledge that while scientific data supporting MAP augmentation are mainly derived from cervical SCI studies, clinicians may choose to maintain MAP > 85 mmHg to improve neurological outcomes 1
French guidelines from 2020 suggest a more conservative approach, recommending MAP > 70 mmHg during the first week after injury, noting insufficient evidence to recommend levels over 70 mmHg 1
Evidence Supporting MAP > 85 mmHg
A 2021 study demonstrated that patients with a higher proportion of MAP measurements ≥85 mmHg showed greater neurological improvement as measured by ASIA impairment scale changes 2
Systematic review evidence suggests that based on the highest level of evidence available (though still limited), MAP goals of 85-90 mmHg for 5-7 days should be considered 3
The most recent 2024 clinical practice guideline suggests a MAP range with a lower limit of 75-80 mmHg and an upper limit of 90-95 mmHg, though this recommendation is considered weak due to very low-quality evidence 4
Duration of MAP Augmentation
Most guidelines and studies recommend maintaining elevated MAP for 5-7 days post-injury 1, 3
Recent evidence suggests that a duration of 3-7 days may be appropriate, though this recommendation is also based on low-quality evidence 4
The correlation between MAP level and neurological improvement appears strongest in the first 2-3 days after admission 1
Practical Considerations and Caveats
Continuous arterial pressure monitoring via arterial catheter is recommended as studies show MAP is below target approximately 25% of the time without close monitoring 1
The need for vasopressors correlates with injury severity (lower admission ASIA motor scores), but one study found that episodes of relative hypotension did not affect ASIA motor score changes during acute hospitalization 5
Norepinephrine may be the preferred vasopressor for cervical and upper thoracic injuries, while phenylephrine or norepinephrine may be appropriate for mid to lower thoracic injuries 3, 6
Important Limitations of Current Evidence
There are no randomized controlled trials comparing neurological outcomes at different MAP targets 1
Most recommendations are based on retrospective studies, small prospective cohorts without control groups, or expert opinion 3, 4
One study questioned whether arbitrarily elevated MAP goals are efficacious, finding that episodes of relative hypotension below various theoretical MAP targets did not affect functional outcomes 5
While the evidence has limitations, maintaining MAP > 85 mmHg for 5-7 days represents the current best practice based on available guidelines and research, with the goal of optimizing neurological recovery after spinal cord injury in patients undergoing cervical spine surgery.