Influence of Anesthetic Temperature on Cephalad Sensory Blockade With Spinal Anesthesia

Study Overview
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Brief Summary
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Several factors influence the extension of anesthetic mixture during spinal anesthesia including anesthetic gravity, body position, drug volume, and drug-delivering velocity. However, the effect of temperature of anesthetic mixture on the cephalad sensory blockade is hitherto unknown. The investigators hypothesized that different temperatures of the anesthetic mixture had different velocity of extension after spinal anesthesia. In addition, previous studies suggest that parturients have relative higher sensitivity to temperature. Herein the investigators proposed that the temperature of anesthetic mixture had more extensive effect on the cephalad sensory blockade with spinal anesthesia for cesarean delivery.

Official Title
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Influence of Anesthetic Temperature on Cephalad Sensory Blockade With Spinal Anesthesia for Cesarean Delivery

Conditions
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Cesarean Delivery

Intervention / Treatment
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* Drug: bupivacaine/fentanyl/morphine


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Nulliparous women > 18 years and < 45 years Exclusion Criteria: Allergy to opioids, a history of the use of centrally-acting drugs of any sort, chronic pain and psychiatric diseases records Participants younger than 18 years or older than 45 years Those who were not willing to or could not finish the whole study at any time Alcohol addictive or narcotic dependent patients Subjects with a nonvertex presentation Diagnosed diabetes mellitus and pregnancy-induced hypertension Twin gestation and breech presentation Pregnant fever

Ages Eligible for Study
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Minimum Age: 19 Years
Maximum Age: 45 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: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: 1<br>Mixture of anesthetic including hyperbaric bupivacaine 12 mg, fentanyl 10 microg and morphine 200 microg, with the temperature of 20 degree celsius | Drug: bupivacaine/fentanyl/morphine<br>* Hyperbaric bupivacaine 12 mg, fentanyl 10 microg and morphine 200 microg<br>|
| Experimental: 2<br>Mixture of anesthetic including hyperbaric bupivacaine 12 mg, fentanyl 10 microg and morphine 200 microg, with the temperature of 10 degree celsius | Drug: bupivacaine/fentanyl/morphine<br>* Hyperbaric bupivacaine 12 mg, fentanyl 10 microg and morphine 200 microg<br>|
| Experimental: 3<br>Mixture of anesthetic including hyperbaric bupivacaine 12 mg, fentanyl 10 microg and morphine 200 microg, with the temperature of 15 degree celsius | Drug: bupivacaine/fentanyl/morphine<br>* Hyperbaric bupivacaine 12 mg, fentanyl 10 microg and morphine 200 microg<br>|
| Experimental: 4<br>Mixture of anesthetic including hyperbaric bupivacaine 12 mg, fentanyl 10 microg and morphine 200 microg, with the temperature of 25 degree celsius | Drug: bupivacaine/fentanyl/morphine<br>* Hyperbaric bupivacaine 12 mg, fentanyl 10 microg and morphine 200 microg<br>|
| Experimental: 5<br>Mixture of anesthetic including hyperbaric bupivacaine 12 mg, fentanyl 10 microg and morphine 200 microg, with the temperature of 30 degree celsius | Drug: bupivacaine/fentanyl/morphine<br>* Hyperbaric bupivacaine 12 mg, fentanyl 10 microg and morphine 200 microg<br>|
| Experimental: 6<br>Mixture of anesthetic including hyperbaric bupivacaine 12 mg, fentanyl 10 microg and morphine 200 microg, with the temperature of 35 degree celsius | Drug: bupivacaine/fentanyl/morphine<br>* Hyperbaric bupivacaine 12 mg, fentanyl 10 microg and morphine 200 microg<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Maximum cephalad sensory blockade to pinprick, cold and touch |  | From the delivery of anesthetic mixture to 15 min immediate after spinal anesthesia | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Velocity of the sensory blockade at identical body position |  | From the delivery of anesthetic mixture to 15 min immediate after spinal anesthesia | 
| The total dose of phenylephrine required to maintain baseline arterial blood pressure |  | From the delivery of anesthetic mixture to 25 min after spinal anesthesia | 
| Time interval of the occurrence of the hypotension |  | From the delivery of the anesthetic mixture to 25 min after spinal anesthesia | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Temperature, Spinal anesthesia, Cesarean section, Cephalad sensory blockade, Regional anesthesia