Orthostatic Hypotension | An Open Label Trial to Decrease Signs and Symptoms of Orthostatic Hypotension Using Midodrine or Intravenous Fluid Bolus in Patients Following Total Hip Arthroplasty

Orthostatic Hypotension research study

What is the primary objective of this study?

Orthostatic hypotension following total hip arthroplasty is known to limit the ability of patients to perform physical therapy (PT) and increase the length of hospital stay and costs. Our goal is to prospectively study the effects of oral midodrine on the signs and symptoms of orthostatic hypotension in 20 patients and the effects of intravenous fluid on the signs of symptoms of orthostatic hypotension in 10 patients. Midodrine will be administered to patients with suspected low SVV, and an intravenous fluid bolus will be administered to patients with low CO. 120 patients will be consented with a view to studying 30 patients who meet the inclusion criteria for orthostatic hypotension. Patients who receive midodrine or the fluid bolus will undergo hemodynamic measurements at 30 min, 1 hr, 2 hrs, 3 hrs, and 4 hrs post-intervention. All patients will undergo measurements for blood pressure, arterial augmentation index, and heart rate at baseline (pre-op; holding area) and the time of first PT attempt. Patients will be monitored up to post-operative day 3. The working hypothesis is that midodrine or fluid therapy will significantly raise the mean arterial blood pressure (MAP) by 5 mmHg+ and/or cause a significant change in the Orthostatic Hypotension Questionnaire (characterized by a two-point improvement in symptom score).

Who is eligible to participate?

Inclusion Criteria: - Patients of participating surgeons undergoing unilateral primary total hip arthroplasty - Ages 18-90 - English-speaking - If the patients are diagnosed with orthostatic hypotension (fall in SBP of at least 20 mmHg or DBP of at least 10 mmHg within 3 min of assuming a sitting/standing position) Exclusion Criteria: - Body mass index > 40 - Low ejection fraction (<50%) - Clinical diagnosis of congestive heart failure - Aortic insufficiency characterized as greater than moderate - Severe uncontrolled hypertension - Symptomatic bradycardia (HR < 50 bpm and symptoms) - Creatinine > 1.2 mg/dl - Hepatic insufficiency - Severe respiratory disease in which supplemental oxygen is required - History of severe urinary retention - Use of MAO inhibitors - Severe supine hypertension (SBP >= 150 mmHg or DBP >= 90 mmHg) - History of visual problems and using fludrocortisone acetate - Contraindication for repeated BP measurements - Revision THA and additional procedures - Clonidine use

Which medical condition, disease, disorder, syndrome, illness, or injury is researched?

Orthostatic Hypotension

Study Interventions

Interventions can include giving participants drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available or noninvasive approaches such as surveys, education, and interviews.

Drug:Midodrine10 mg, p.o., once, on day of surgery after first physical therapy session

Other:Intravenous fluid bolus15 cc/kg, once, on day of surgery after first physical therapy session

Study Arms

Research studies and clinical trials typically have two or more research arms. An arm is a group of people who receive the same treatment in the study.

MidodrinePatients who are diagnosed with orthostatic hypotension at their first physical therapy session and have an SVV<15 will be given oral midodrine, 10 mg, once.

Intravenous fluid bolusPatients who are diagnosed with orthostatic hypotension at their first physical therapy session and have an SVV>=15 will be given intravenous fluid bolus, 15 cc/kg, once.

Control (no intervention)Patients who are NOT diagnosed with orthostatic hypotension at their first physical therapy session will be given the interventions.

Study Status


Start Date: June 2014

Completed Date: January 2015

Phase: N/A

Type: Interventional


Primary Outcome: Change in Orthostatic Hypotension Questionnaire Score

Secondary Outcome: Length of Stay

Study sponsors, principal investigator, and references

Principal Investigator:

Lead Sponsor: Hospital for Special Surgery, New York


More information:

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