Spinal Cord Injury

• Primary SCI:* Any disruption of normal spinal cord anatomy and physiology at the time of injury.

• Secondary SCI:* Subsequent damage caused by:
• Hypoxemia
• Hypoperfusion
• Inflammation

Secondary injury causes further cell death in the injury "penumbra" — surrounding tissue that worsens functional prognosis if lost.

Early ICU care improves functional prognosis by limiting secondary injury.

MAP Targets

• Avoid hypotension — MAP goal 85 mmHg × 7 days*

The decision to use MAP 85–90 mmHg for 7 days must be weighed against limitations of the evidence, risks of vasopressor use, prolonged immobilization, invasive monitoring, and resource consumption.

Hemodynamic Management

1. Volume resuscitation first — restore normovolemia; avoid fluid overload
2. Vasopressors if normovolemia is achieved and MAP remains inadequate
3. Choose pressors with both alpha and beta activity (e. g., norepinephrine)

• Uniform grading system for communication between care teams
• Prognostic framework for treatment planning and patient discussions

• (See ASIA impairment scale A–E)*

Neurogenic Shock

• Definition: Severe vasodilation from loss of sympathetic tone to the distal vasculature
• Unopposed parasympathetic effect on peripheral vascular networks → peripheral blood pooling
• More common if injury is at or above T6

• Physiologic effects:*
• Hypotension
• Bradycardia
• Loss of preload to the heart
• Sustained → end organ damage, lactic acidosis, cardiovascular collapse

Spinal Shock

• Definition: A physical exam finding — significant muscle flaccidity, loss of sensory and motor functions below the level of injury
• This is a clinical/neurological phenomenon, not a hemodynamic state

Can occur in complete or incomplete SCI at or above T6.

• Trigger:* Stimulus below the level of cord injury (bladder distension, bowel impaction, pressure sores, occult fractures) → unregulated sympathetic response below injury level → reflexive parasympathetic response above the injury.

Symptoms

• Acute hypertension (hypertensive crisis)
• Headache
• Diaphoresis
• Flushing above level of injury
• Anxiety, nausea
• Nasal congestion
• Blurred vision

Complications of Untreated Severe AD

• Myocardial infarction
• Stroke
• Seizures
• Pulmonary edema

Treatment

1. Sit patient upright
2. Remove tight-fitting garments
3. Remove the precipitating stimulus (most commonly: fecal impaction or obstructed Foley)
4. If hypertension persists: short-acting antihypertensive (e. g., nifedipine, captopril, nitroglycerin cream)

• Prevention:* Avoid potential precipitants (Foley patency, bowel regimen, pressure offloading).

• MAP Calculator

• Adapted from SurgCritCare. org spinal cord injury content. Verify MAP goals and vasopressor protocols against current institutional standards and neurosurgery/attending guidance.*