Continuous Spinal Anesthesia With Hypobaric Bupivacaine to Preserve Hemodynamics in Elderly

Study Overview
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Brief Summary
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The study evaluates the potential beneficial effects on hemodynamics when hypobaric bupivacaine is used instead of isobaric bupivacaine in continuous spinal anesthesia for surgical repair of hip fracture in elderly patients. Half of the patients will receive hypobaric bupivacaine and the over half will reveive isobaric bupivacaine and hemodynamic data will be compared.

Detailed Description
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Anesthesia for surgical repair of hip fracture is still controversial. Large retrospective studies and systematic reviews failed to demonstrate the superiority of either general or regional anesthesia. However, continuous spinal anesthesia has been shown to preserve hemodynamics better than general and single shoot spinal anesthesia. However, hypotension still occurs with continuous spinal anesthesia. Unilateral spinal anesthesia may be achieved by hypobaric bupivacaine when patients are in the lateral position. Unilateral spinal anesthesia is more effective in preserving hemodynamics by limiting the spread of the sympathetic blockade to the operated side. Our goal is to show that the use of hypobaric rather than isobaric bupivacaine in continuous spinal anesthesia for surgical repair of hip fracture reduces incidence of hypotension.

Official Title
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Hypobaric Rather Than Isobaric Bupivacaine to Prevent Anesthesia-induced Hypotension in Patients Undergoing Surgical Repair of Hip Fracture Under Continuous Spinal Anesthesia: a Prospective Randomized Controlled Study.

Conditions
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Hip Fracture, Hypotension

Intervention / Treatment
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* Procedure: continuous spinal anesthesia
* Drug: hypobaric bupivacaine
* Drug: isobaric bupivacaine
* Drug: ephedrine


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients aged more than 65 years and scheduled for a surgical repair of a hip fracture. Exclusion Criteria: contraindication to spinal anesthesia or peripheral nerve blocks including hemostasis anomalies, local infection, allergic reaction to local anesthetics. dementia. consent refusal.

Ages Eligible for Study
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Minimum Age: 65 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: hypobaric<br>continuous spinal anesthesia with 2,5 mg boluses of hypobaric bupivacaine, prepared diluting each 1 ml of 0.5% isobaric bupivacaine with 1 ml of sterile water. | Procedure: continuous spinal anesthesia<br>* Spinal puncture performed with a 19-gauge Tuohy needle at the L4-L5 or L3-L4 interspace using a midline approach. 3 cm of a 22-gauge catheter introduced through the needle, directed to the fractured side.<br>Drug: hypobaric bupivacaine<br>* hypobaric bupivacaine was prepared diluting each 1 ml of 0.5% isobaric bupivacaine with 1 ml of sterile water.<br>Drug: ephedrine<br> <br> |
| Active Comparator: isobaric<br>continuous spinal anesthesia with 2,5 mg boluses of 0.5% isboaric bupivacaine | Procedure: continuous spinal anesthesia<br>* Spinal puncture performed with a 19-gauge Tuohy needle at the L4-L5 or L3-L4 interspace using a midline approach. 3 cm of a 22-gauge catheter introduced through the needle, directed to the fractured side.<br>Drug: isobaric bupivacaine<br>* 0.5% isobaric bupivacaine<br>Drug: ephedrine<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The percentage of patients who experienced at least one episode of hypotension during surgery (fall of more than 20% of systolic blood pressure) among the 2 groups |  | 2 hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Total bupivacaine consumption | total dose of bupivacaine needed to perform the surgery (approximate duration of surgery : 2 hours) | 2 hours | 
| The percentage of patients who experienced at least one episode of bradycardia (heart rate<50 bpm) among the 2 groups |  | 2 hours | 
| vasopressor use | total ephedrine injected if hypotension occurred (approximate duration of surgery : 2 hours). | 2 hours | 
| fluid infusion | total fluid infused intravenously at the end of surgery (approximate duration of surgery : 2 hours). | 2 hours | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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hip fracture, elderly, continous spinal anesthesia, hypobaric bupivacaine, isobaric bupivacaine, hypotension