Fixed Dose Spinal Bupivacaine for Cesarean Delivery

Study Overview
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Brief Summary
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The study is designed to compare the effectiveness of spinal anesthesia performed with fixed dose of hyperbaric bupivacaine regardless of patient's height and weight and anesthesia with the dose of bupivacaine that is adjusted to their height. Our clinical experience shows that spinal anesthesia using specific, relatively high dose of hyperbaric bupivacaine combined with opioid is very effective, regardless of parturient's weight and height, provides very good surgical conditions and assures patient's comfort while the rate of anesthesia - related complications is similar or less. Therefore, using height-adjusted protocols, although preferred in some centres, might not be necessary in order to provide good anaesthesia for cesarean delivery. Fixed dose regimen may have some additional advantages in obstetric anesthesia settings, as many of cesareans are performed out of hours, giving less room for mistakes in less experienced hands. Two groups of parturients undergoing cesarean section are to be compared: anesthetized with fixed-dose regimen (intervention group) and anesthetized with height-adjusted dose regimen (control group). Patients are going to be randomized to one of the above groups, two anesthetists will be involved in anesthetic procedure: anesthetist that looks after the patient throughout the procedure will be blinded to the dose of anesthetic given intrathecally. Therefore his judgment of anesthetic effectiveness is not going to be biased and all patients will receive the same perioperative care in terms of fluid therapy, management of possible anesthesia - related complications and postoperative pain control. Rate of effective spinal anesthetics, defined as adequate block level and no need for additional intraoperative analgesia has been established as primary outcome measure. Secondary outcome measures are rate of complications and amount of opioids used postoperatively. These are going to be statistically compared.

Official Title
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Fixed Dose Versus Height - Adjusted Dose of Intrathecal Hyperbaric Bupivacaine With Opioid for Cesarean Delivery: a Prospective Double-blinded Randomized Trial

Conditions
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Spinal Anesthesia, Cesarean Section

Intervention / Treatment
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* Drug: Fixed dose of 12.5mg bupivacaine
* Drug: Height-adjusted dose of bupivacaine


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: singleton pregnancy above 37Hbd scheduled for elective cesarean section ASA 1 or 2 Exclusion Criteria: absolute contraindications to spinal anesthesia delivery in progress non-singleton pregnancy BMI>35 ultrasound - based estimation of fetal weight below 10 percentile pregnancy-induced hypertension more than 2 cesarean sections in patient's medical history significantly increased risk of obstetric hemorrhage (placenta previa)

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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Female

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: Supportive Care
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Fixed dose of 12.5mg bupivacaine<br>Participants that receive the same dose of intrathecal bupivacaine and 25mcg of fentanyl, regardless of their height. | Drug: Fixed dose of 12.5mg bupivacaine<br>* Spinal anesthesia performed with 12,5mg of bupivacaine with 25mcg fentanyl for cesarean section<br>|
| Active Comparator: Height-adjusted dose of bupivacaine<br>Participants that receive the dose of intrathecal bupivacaine adjusted to their height and 25mcg of fentanyl | Drug: Height-adjusted dose of bupivacaine<br>* Spinal anesthesia performed with height-adjusted dose of bupivacaine with 25mcg fentanyl for cesarean section<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Adequacy of spinal anesthesia | Level of surgical anesthesia at least T5 and no need for additional intraoperative analgesia | 60min | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of complications | Hypotension, bradycardia, nausea, vomiting, | 60min | 
| Postoperative opioid consumption | Time to the first dose of morphine and total amount of morphine used postoperatively | 24hours | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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failed spinal, intrathecal bupivacaine, hyperbaric bupivacaine