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From the Research
Spinal canal stenosis can cause hypotension, and its management should focus on maintaining adequate blood pressure while addressing the underlying stenosis. The primary complication of hypotension in patients with spinal canal stenosis is reduced perfusion pressure to the already compromised spinal cord, which can worsen neurological symptoms or cause permanent damage. Management of hypotension in these patients should prioritize maintaining adequate blood pressure, and according to a study published in 2019 1, midodrine and methylxanthines can be suggested as therapeutic options for managing symptoms in spinal cord injury patients, which may also be applicable to patients with spinal canal stenosis. For acute hypotension, the following steps can be taken:
- Intravenous fluid resuscitation with normal saline or lactated Ringer's solution (500-1000mL bolus, then titrated to response) should be initiated promptly.
- If fluids are insufficient, vasopressors such as phenylephrine (50-200 mcg/min) or norepinephrine (0.01-0.3 mcg/kg/min) may be necessary to maintain mean arterial pressure above 85-90 mmHg to ensure adequate spinal cord perfusion.
- Patients should be positioned with the head of bed flat or slightly elevated to optimize spinal blood flow.
- Medications that can exacerbate hypotension, such as antihypertensives, should be temporarily held or dose-reduced.
- Continuous hemodynamic monitoring is essential, particularly in perioperative settings where anesthesia-induced hypotension is common. For long-term management, treating the underlying stenosis through surgical decompression may be necessary, while maintaining euvolemia and avoiding medications that precipitate hypotension, as suggested by a study published in 2016 2. The rationale for aggressive blood pressure management stems from the tenuous blood supply to the spinal cord in stenosis, where the normal autoregulatory mechanisms may be impaired, making the cord particularly vulnerable to hypoperfusion injury. Some key points to consider in the management of hypotension in patients with spinal canal stenosis include:
- Maintaining adequate blood pressure to ensure spinal cord perfusion
- Avoiding medications that can exacerbate hypotension
- Positioning patients to optimize spinal blood flow
- Continuous hemodynamic monitoring, particularly in perioperative settings
- Treating the underlying stenosis through surgical decompression, if necessary.