Combined Colloid Preload And Crystalloid Coload Versus Crystalloid Coload During Spinal Anesthesia for Cesarean Delivery

Study Overview
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Brief Summary
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The study will compare one technique of fluid administration (combined colloid preload and crystalloid colaod) with another one (crystalloid coload) during elective cesarean delivery performed under spinal anesthesia.

Detailed Description
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This randomized, controlled, double-blind study will be conducted on ASA physical status II parturients with full-term singleton pregnancy undergoing elective cesarean delivery under spinal anesthesia. Participants will receive either 500 mL colloid preload and 500 mL crystalloid coload (Combination group) or 1000 mL crystalloid coload (Coload group). Systolic blood pressure will be recorded every minute and ephedrine will be administered when hypotension occurs according to a predefined protocol. The total ephedrine dose, time to the first ephedrine dose, heart rate, inferior vena cava diameter, nausea/vomiting, and neonatal Apgar scores will be recorded.

Official Title
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Combined Colloid Preload And Crystalloid Coload Versus Crystalloid Coload During Spinal Anesthesia for Cesarean Delivery

Conditions
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Anesthesia, Spinal, Cesarean Section

Intervention / Treatment
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* Drug: 500 mL Colloid Preload
* Procedure: Spinal Anesthesia
* Drug: Intrathecal Bupivacaine
* Drug: Intrathecal Fentanyl
* Drug: 500 mL Crystalloid Coload
* Drug: 1000 mL Crystalloid Coload
* Procedure: Cesarean Delivery
* Radiation: Ultrasound Assessment of the Inferior Vena Cava
* Drug: Intravenous Ephedrine


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: American Society of Anesthesiologists physical status II parturients Full term, singleton pregnancy Elective cesarean delivery under spinal anesthesia Exclusion Criteria: Age <19 or > 40 years Height <150 cm Weight <60 kg Body mass index ≥40 kg/m2 Contraindications to spinal anesthesia (increased intracranial pressure, coagulopathy, or local skin infection) Chronic or pregnancy-induced hypertension Hemoglobin <10 gm/dL. Diabetes mellitus, cardiovascular, cerebrovascular, or renal disease Polyhydramnios or known fetal abnormalities

Ages Eligible for Study
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Minimum Age: 19 Years
Maximum Age: 40 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: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Combination<br>500 mL colloid preload and 500 mL crystalloid coload. Cesarean delivery performed under spinal anesthesia (intrathecal bupivacaine 12.5 mg and intrathecal fentanyl 15 µg). Ultrasound assessment of the Inferior vena cava diameter. Intravenous ephedrine will be administered. | Drug: 500 mL Colloid Preload<br>* 6% hydroxyethyl starch 130/0.4 in 0.9% sodium chloride (voluven®) 500 mL will be rapidly infused before spinal anesthesia<br>Procedure: Spinal Anesthesia<br>* Performed at the L3-L4 or L4-L5 interspace using 27- or 25-gauge spinal needle<br>Drug: Intrathecal Bupivacaine<br>* Bupivacaine 12.5 mg (2.5 mL 0.5%) will be administered in the subarachnoid space<br>Drug: Intrathecal Fentanyl<br>* Fentanyl 15 µg will be administered in the subarachnoid space<br>Drug: 500 mL Crystalloid Coload<br>* Ringer acetate 500 mL will be rapidly infused immediately after intrathecal injection<br>Procedure: Cesarean Delivery<br>* Lower segment cesarean section using the Pfannenstiel incision<br>Radiation: Ultrasound Assessment of the Inferior Vena Cava<br>* The inferior vena cava largest and smallest diameters will be measured proximal to the opening of the hepatic veins in the longitudinal axis with the M-mode using a 5-2 MHz curved array ultrasound probe placed longitudinally in the subxiphoid region<br>Drug: Intravenous Ephedrine<br>* Intravenous ephedrine 3, 5, and 10 mg will be administered when Systolic blood pressure decreases below 90%, 80%, and 70% of baseline, respectively.<br>|
| Active Comparator: Coload<br>1000 mL crystalloid coload. Cesarean delivery performed under spinal anesthesia (intrathecal bupivacaine 12.5 mg and intrathecal fentanyl 15 µg). Ultrasound assessment of the Inferior vena cava diameter. Intravenous ephedrine will be administered. | Procedure: Spinal Anesthesia<br>* Performed at the L3-L4 or L4-L5 interspace using 27- or 25-gauge spinal needle<br>Drug: Intrathecal Bupivacaine<br>* Bupivacaine 12.5 mg (2.5 mL 0.5%) will be administered in the subarachnoid space<br>Drug: Intrathecal Fentanyl<br>* Fentanyl 15 µg will be administered in the subarachnoid space<br>Drug: 1000 mL Crystalloid Coload<br>* Ringer acetate 1000 mL will be rapidly infused immediately after intrathecal injection<br>Procedure: Cesarean Delivery<br>* Lower segment cesarean section using the Pfannenstiel incision<br>Radiation: Ultrasound Assessment of the Inferior Vena Cava<br>* The inferior vena cava largest and smallest diameters will be measured proximal to the opening of the hepatic veins in the longitudinal axis with the M-mode using a 5-2 MHz curved array ultrasound probe placed longitudinally in the subxiphoid region<br>Drug: Intravenous Ephedrine<br>* Intravenous ephedrine 3, 5, and 10 mg will be administered when Systolic blood pressure decreases below 90%, 80%, and 70% of baseline, respectively.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Total ephedrine dose |  | intraoperative | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence of hypotension | Hypotension: Systolic blood pressure <80% of baseline | intraoperative | 
| Incidence of severe hypotension | Severe hypotension: Systolic blood pressure <70% of baseline | intraoperative | 
| Time to the first ephedrine dose |  | intraoperative | 
| Heart rate |  | intraoperative | 
| Inferior vena cava largest and smallest diameters |  | Baseline, at 1 and 5 minutes after intrathecal injection, delivery | 
| Inferior vena cava collapsibility index | Collapsibility index = (Largest diameter - Smallest diameter) / Largest diameter | Baseline, at 1 and 5 minutes after intrathecal injection, delivery | 
| Incidence of nausea and/or vomiting |  | intraoperative | 
| Neonatal Apgar score |  | At 1 and 5 minutes after delivery |