Treatment of Post-SCI Hypotension

While treatment strategies for OH have been identified for use in persons with acute SCI, the field of SCI medicine lacks a gold standard for treatment thresholds and well-defined outcome parameters. Comprehensively documenting the impact of orthostatic hypotension (OH), regardless of symptoms, during acute rehabilitation and identifying the effects of two different treatment approaches on therapy participation and adherence to an intended rehabilitation plan could have a significant impact on clinical practice in the acute rehabilitation setting following SCI.

Baseline Testing: Subjects will visit the testing laboratory on the SCI Rehabilitation Unit for baseline data collection, prior to initiation of the treatment protocol. Upon arrival, subjects will be placed in the supine position on an adjustable surface for instrumentation, which will be conducted in a quiet, dimly lit, thermo-neutral testing environment. After a 20-minute period of quiet rest, a 10-minute sample of supine heart rate (HR), respiratory rate, BP and CBF velocity data will be collected. Venous occlusion plethysmography (Vop) will be collected in the supine position for two 5-minute periods. After the supine data collection, subjects will be passively moved into the seated position, with the knees and hips at 90°, for the 10-minute seated data collection period. Subjects will be asked to complete two surveys related to AD and OH symptomology. Finally, subjects will be fitted with a 24-hour HR and BP monitor and will be asked to go about their normal routine. A record of all daily activities including rehabilitation, medications, eating and sleep/wake times will be logged. This testing session should take approximately 1 hour.

Daily Testing: Every day supine and seated BP measurements will be performed at least three times per day. These BP assessments will be recorded in the supine and seated positions in the subject's room by a patient care associate who is blind to the study arm allocation. For every scheduled physical and occupational therapy session, the treating therapist will be asked to complete a brief 6 question survey to document if that session was altered, disrupted, or missed due to hypotension (Therapist Reported Version). The subject will also be asked to complete a brief survey to determine if from their perspective the session was altered, disrupted or missed due to hypotension (Subject Reported Version). In addition, every day a co-investigator and the attending physician for that subject will complete an EMR review of queried BP values within the previous 24 hours, symptoms of low BP, adverse events related to high or low BP, and will review (and act upon for the usual care arm) the protocol treatment decision tree.

Weekly Testing: At weekly intervals of between 6 and 8 days, subjects will be asked to visit the testing laboratory on the SCI Rehabilitation Unit. Procedures for the weekly testing sessions will be the same as for the Baseline Testing. The 24-hour BP assessment will be conducted twice weekly.

Discharge Testing: At discharge subjects will undergo similar testing as described during the Baseline and Weekly Testing with the addition of the Patient Global Impression of Change survey, which will be administered by the Mount Sinai Site Research Assistant.

Eligibility Criteria:
Inclusion Criteria:

* Any level of injury;
* Any AIS grade of SCI;
* Non-ventilator dependent
* Primarily wheelchair dependent for mobility;
* Duration of injury \< 1 year
* Systolic BP less than 110 mmHg and/or diastolic BP less than 70 mmHg for males.
* Systolic BP less than 100 mmHg and/or diastolic BP less than 70 mmHg for females
* Primary Language is English.
* Able to provide informed consent

Exclusion Criteria:

* Have insufficient mental capacity to independently provide informed consent
* Have insufficient English speaking or reading ability to provide informed consent or complete assessments in English
* Have contraindications to the use of midodrine hydrochloride
* Are pregnant