Use of Intrathecal Fentanyl and Development of Hyperalgesia in Patients Undergoing Elective Cesarean

Study Overview
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Brief Summary
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Opioid analgesic drugs are the main treatment of patients during anesthesia. Although highly effective, their use is not without problems. One is the increasing requirement of these address the same nociceptive stimulus. Opioid induced hyperalgesia could be an explanation studies in animal models. Through mechanisms where N-methyl-D-aspartate receptors, glutamatergic system disturbances and changes in intracellular calcium regulation involved. The hyperalgesia induced by intrathecal opioids is controversial. The investigators propose a model study in patients undergoing cesarean section to study the secondary hyperalgesia induced based on the study of nociceptive thresholds with two methods opioids: Von Frey filaments and digital algometer. If intrathecal fentanyl is used in spinal anesthesia for elective cesarean section, then, an increase in sensitivity will occur. This increase can be measured by von Frey filaments, expressed in increased requirement clinically opioids.

Official Title
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Use of Intrathecal Fentanyl and Development of Hyperalgesia in Patients Undergoing Elective Cesarean

Conditions
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Complications; Cesarean Section

Intervention / Treatment
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* Drug: H-Bupivacaine
* Drug: Fentanyl


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Pregnant 37 to 41 weeks. American Society of Anesthesiologists classificationI or II. Between 18 and 40 years. Scheduled for elective cesarean section under spinal anesthesia in the Maternity Service of the Clinical Hospital of the Catholic University. Exclusion Criteria: Background Of high risk pregnancy. Twin-pregnancy. Obesity> 30 kg / m 2 before pregnancy. Background Of psychiatric illness. Using Chronic analgesic. AllergyDrug used in protocol. require General anesthesia during surgery

Ages Eligible for Study
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Minimum Age: 18 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: H-Bupivacaine 11.5 mg + fentanyl 25 mcg.<br>Intrathecal administration of Hyperbaric Bupivacaine 1.5 ml 0.75% plus fentanyl 25 mcg. | Drug: H-Bupivacaine<br>* Intrathecal administration of hyperbaric bupivacaine 1.5 ml 0.75%<br>* Other names: Hyperbaric bupivacaine;Drug: Fentanyl<br>* Intrathecal administration of fentanyl 25 mcg<br>|
| Active Comparator: H-Bupivacaine 11.5 mg.<br>Intrathecal administration of Hyperbaric Bupivacaine 1.5 ml 0.75% | Drug: H-Bupivacaine<br>* Intrathecal administration of hyperbaric bupivacaine 1.5 ml 0.75%<br>* Other names: Hyperbaric bupivacaine;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Punctate - Von frey (grams) |  | Change from Baseline in punctate sensibility at 48 hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Pressure pain - algometer (kg/cm/cm) |  | Change from Baseline in pressure pain at 48 hours | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Anesthesia, Spinal and Epidural, Adverse Effect, Complications