: Oral Midodrine for Prophylaxis Against Post Spinal Anaesthesia Hypotension During Hip Arthroplasty in Elderly Population: A Randomized Controlled Trial
Trial Snapshot
- Phase
- Not Applicable
- Status
- Completed
- Sponsor
- Cairo University
- Enrollment
- 58
- Locations
- 1
- Primary Endpoint
- Intraoperative ephedrine consumption
Study Overview
Brief Summary
Hip fracture is a common and serious healthcare problem which commonly affects elderly populations. The common route of anesthesia for hip arthroplasty is spinal anesthesia. Elderly populations are characterized by high incidence of post spinal anesthesia hypotension; furthermore, elderly patients commonly have systemic medical disorder; therefore, this population is highly vulnerable to perioperative hypotension. Moreover , intraoperative hypotension during hip surgery has been recently recognized as a major risk factor for postoperative morbidity and mortality.
Through the effect of spinal anesthesia on sympathetic system Veno-dilatation, decreased venous return, and consequently decreased cardiac output and hypotension will be induced. Vasopressors are commonly used for prophylaxis against post spinal hypotension in different patient subgroups. The commonly used drugs are alpha-adrenoreceptor agonists such as ephedrine, phenylephrine, and recently norepinephrine. All these agents are effective in maintenance of blood pressure; however, they have some disadvantages; ephedrine is commonly associated with tachycardia, phenylephrine and norepinephrine are associated with bradycardia. All the former mentioned drugs are used intravenously.
Midodrine hydrochloride is another alpha-adrenoreceptor agonist drug which is used for management of various hypotensive disorders. Midodrine is the prodrug which is metabolized to desglymidodrine which is a direct arteriolar and venous vasopressor. Midodrine is characterized by being an oral drug, with minimal central nervous system side effects, and good oral bioavailability. No studies had evaluated the efficacy of midodrine for prophylaxis against post-spinal anesthesia hypotension in elderly population.
Aim of the work:
This thesis aims to evaluate the efficacy and safety of oral 5 mg of midodrine compared to placebo in prophylaxis against post-spinal hypotension in elderly patients undergoing hip arthroplasty
Detailed Description
Participants will be instructed to fast for 6 hours for solid light meals and 2 hours for clear fluids. The baseline blood pressure will be measured in the preparation room 90 min before spinal anaesthesia as the mean of three measurements with difference of less than 10%. The patients will receive the study drug after measurement of the baseline blood pressure reading. The patient will be monitored for blood pressure and heart rate at 15 min intervals after administration of the study drug. In the operating room, routine monitors (Electrocardiogram, pulse oximetry, and non-invasive blood pressure monitor) will be applied; intravenous line will be secured, and routine pre-medications will be administrated.
Preoperative evaluation of volume status:
All patients will be assessed for volume status before spinal block through evaluation of the inferior vena cava (IVC) collapsibility, and patients who will show IVC collapsibility > 36% will be considered fluid responders and will receive Ringer's lactate solution, 6 mL/kg ideal body weight over 15 minutes.
IVC collapsibility will be calculated as: (maximum IVC diameter - minimum IVC diameter) / maximum IVC diameter.
Anaesthetic management:
Study Design
- Study Type
- Interventional
- Allocation
- Randomized
- Intervention Model
- Parallel
- Primary Purpose
- Prevention
- Masking
- Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Eligibility Criteria
- Ages
- 65 Years to — (Older Adult)
- Sex
- All
- Accepts Healthy Volunteers
- No
Inclusion Criteria
- •Elderly patients (>65).
- •ASA I-II-III.
- •Scheduled for hip joint surgery under spinal anaesthesia
Exclusion Criteria
- •• Uncontrolled hypertension
- •Liver cell failure (child B or C).
- •Chronic renal failure on regular dialysis
- •Contraindications of spinal anaesthesia
- •History of allergy to midodrine
- •Cardiac morbidities (impaired contractility with ejection fraction < 50%, heart block, arrhythmias, tight valvular lesions).
- •Acute renal disease, urinary retention
- •Patients on negative chronotropic drugs (such as beta blocker) or vasoconstrictor
- •Patients with glaucoma
Arms & Interventions
control group
oral metoclopramide 10 mg, Metoclopramide tablet was chosen as a placebo because it has the same appearance of midodrine tablet with no cardiovascular effects
Intervention: Metoclopramide (Drug)
Midodrine group
oral midodrine tablet (5 mg)
Intervention: Midodrine Oral Tablet (Drug)
Outcomes
Primary Outcomes
Intraoperative ephedrine consumption
Time Frame: 1 minutes after spinal injection until 45 minutes after induction of spinal anesthesia
mg
Secondary Outcomes
- Incidence of post-spinal hypotension(1 minutes after spinal injection until 45 minutes after induction of spinal anesthesia)
- Incidence of bradycardia(1 minutes after spinal injection until 45 minutes after induction of spinal anesthesia)
- mean arterial pressure(1 minute after intervention, every 15 minutes after intervention for 90 minutes, every 2 minutes after spinal anesthesia for 20 min, then every 5 minutes until the end of the procedure)
- Incidence of severe spinal induced hypotension(1 minutes after spinal injection until 45 minutes after induction of spinal anesthesia)
- heart rate(1 minute after intervention, every 15 minutes after intervention for 90 minutes, every 2 minutes after spinal anesthesia for 20 min, then every 5 minutes until the end of the procedure)
Investigators
Ahmed Hasanin
Principal Investigator
Cairo University