Dose Escalation of Dexamethasone to Increase Duration of Transversus Abdominal Plane Block Following Cesarean Section
- Conditions
- Post Surgical Pain
- Interventions
- Drug: Normal saline 1mlDrug: Normal saline 0.5ml
- Registration Number
- NCT03098420
- Lead Sponsor
- University of Alabama at Birmingham
- Brief Summary
The study aims to improve the care of the obstetric population after cesarean section and improve total patient satisfaction by improving post-surgical pain control with the use of dexamethasone in combination with bilateral TAP blocks. The investigators will utilize a dose-escalation of dexamethasone in the TAP block to observe its effects at specific small doses. It is the hope of the investigator that the studied technique would become utilized routinely for the obstetric population following cesarean section.
The investigators hope to show that the addition of dexamethasone in bilateral TAP blocks will prolong the duration of the block in a dose-dependent fashion. The investigators hope to improve post-operative pain following cesarean section, increase duration of TAP block with use of dexamethasone, decrease overall pain scores in the first 24-48 hours, and decrease opioid requirements after cesarean section.
The primary endpoint will be estimation of duration of TAP block, being assessed within 48 hours after surgery. Secondary endpoints will include pain scores both in PACU and on the floor, average pain scores, time until first opioid administration, total opioid consumption in first 48 hours, use of PONV medications, and overall patient satisfaction.
- Detailed Description
Preoperatively: informed consent will be obtained by a member of this study. The patients will be screened for inclusion/exclusion criteria on day of procedure, and then the participants will be randomized to one of three groups.
Intraoperatively: The anesthesia team involved with care of patient in the operating room will provide routine anesthesia care during the cesarean section including neuraxial anesthesia with intrathecal bupivacaine and morphine.
After completion of the procedure, the patients will receive bilateral TAP block procedure while still in OR. All blocks will include 20mL of 0.5% ropivacaine, and the patients will be randomly assigned a specific dose of dexamethasone at 0mg (given normal saline as control), 2mg, or 4mg. The resident or attending physician supervising the block will be investigators of the study, and they along with the residents performing the blocks will be blinded to the amount of dexamethasone in the injectate.
Postoperatively: The patients will then be monitored in the PACU for approximately 30-60 minutes and then subsequently monitored on an inpatient floor. Pain scores, time until first opioid dose, total opioid requirement will be assessed and recorded. In PACU, these will be recorded every 15-30 minutes. On the inpatient floor, these will be recorded every 6 hours.
Pain scores, average pain scores in first 48 hours, total opioid consumption, time until first opioid use, and PONV medication requirement will also be recorded. These will be recorded by review of the electronic medical record.
Satisfaction scores and estimation of TAP block duration will be assessed and recorded by anesthesia personnel approximately 48 hours post-operatively; these will be subjective evaluations recorded between 24-38 hours postoperatively. The patients will be asked to estimate how long they felt the block lasted. For satisfaction scores, patients will rate their satisfaction subjectively on a scale of 1-10.
Statistical Analysis: all demographic and clinical variables with continuous measures will be expressed as means and standard deviations; categorical factors will be expressed as proportions. For non-normal data, the medians and inter quartile ranges will be displayed. The distribution of the continuous factors will be examined using the Kolmogorov-Smirnov test. For data that are normally distributed, one-way ANOVA will be used to compare groups of data. For data that are not normally distributed, the Kruskal-Wallis test will be used for comparisons. Chi-square and Fisher's exact tests will be used to analyze categorical data. For all comparisons, a value of p \< 0.05 will be considered statistically significant.
Statistical analyses will be performed using SAS for Windows, version 9.2. One-way ANOVA (or the Kruskal-Wallis test, as appropriate) will be used to compare duration of TAP block for the three groups. Linear regression will also be used to test the relationship between duration of block and dexamethasone dose, while controlling for relevant clinical and demographic variables.
One-way ANOVA (or the Kruskal-Wallis test) will be used to compare the groups on post-operative pain scores, opioid requirements, and patient satisfaction scores.
Statistical Power and Sample Size Estimates: Approximately 69 subjects (23 per group) are expected to be enrolled in this study. Given this sample size and assuming that the average duration of TAP block is 18 hours for the control group, 22 hours for the 2 mg of dexamethasone group, and 24 hours for the 4 mg of dexamethasone group, this study will have approximately 80.9% power to detect a difference in block duration, assuming a common standard deviation of 6 hours. If the variability in block time is smaller than 6 hours, this study will have greater power.
Recruitment & Eligibility
- Status
- TERMINATED
- Sex
- Female
- Target Recruitment
- 29
-
Women undergoing cesarean section delivery.
-
Patients classified as American Society of Anesthesiology (ASA) class II or III.
- ASA II: mild systemic disease, pregnancy
- ASA III: severe systemic disease
-
Women ≥ 18 years old
-
Neuraxial anesthesia (spinal) to be used as anesthetic technique intraoperatively for cesarean section (this is the UAB Anesthesiology standard of care).
- Any patient not classified as an ASA I or II.
- General Anesthesia or neuraxial anesthesia with epidural used as anesthetic techniques for cesarean section.
- Allergy/intolerance to local anesthetic or steroids.
- Pre-existing neurological and/or anatomical deficit that would preclude regional block.
- Coexisting coagulopathy such as hemophilia or von Willebrand Disease
- BMI > 40.
- Emergency Cesarean Sections
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- PARALLEL
- Arm && Interventions
Group Intervention Description Control Group Ropivacaine (TAP blocks) 20 patients. Each patient will receive postoperative bilateral TAP blocks (20mL of ropivacaine) and 1mL of normal saline bilaterally (control) with standard intrathecal bupivacaine and morphine. Control Group Normal saline 1ml 20 patients. Each patient will receive postoperative bilateral TAP blocks (20mL of ropivacaine) and 1mL of normal saline bilaterally (control) with standard intrathecal bupivacaine and morphine. 2mg Dexamethasone 2mg Dexamethasone 20 patients. Each patient will receive postoperative bilateral TAP blocks (20mL of 0.5% ropivacaine) with 0.5 mL (2mg) of dexamethasone and 0.5 ml of normal saline split between 2 sides with standard intrathecal bupivacaine and morphine. 2mg Dexamethasone Ropivacaine (TAP blocks) 20 patients. Each patient will receive postoperative bilateral TAP blocks (20mL of 0.5% ropivacaine) with 0.5 mL (2mg) of dexamethasone and 0.5 ml of normal saline split between 2 sides with standard intrathecal bupivacaine and morphine. 2mg Dexamethasone Normal saline 0.5ml 20 patients. Each patient will receive postoperative bilateral TAP blocks (20mL of 0.5% ropivacaine) with 0.5 mL (2mg) of dexamethasone and 0.5 ml of normal saline split between 2 sides with standard intrathecal bupivacaine and morphine. 4mg Dexamethasone 4mg Dexamethasone 20 patients. Each patient will receive postoperative bilateral TAP blocks (20mL of 0.5% ropivacaine) with 20mL of 0.5% ropivacaine) and 1 mL (4mg) of dexamethasone between 2 sides with standard intrathecal bupivacaine and morphine. 4mg Dexamethasone Ropivacaine (TAP blocks) 20 patients. Each patient will receive postoperative bilateral TAP blocks (20mL of 0.5% ropivacaine) with 20mL of 0.5% ropivacaine) and 1 mL (4mg) of dexamethasone between 2 sides with standard intrathecal bupivacaine and morphine. Control Group Morphine 20 patients. Each patient will receive postoperative bilateral TAP blocks (20mL of ropivacaine) and 1mL of normal saline bilaterally (control) with standard intrathecal bupivacaine and morphine. Control Group Bupivacaine Hydrochloride 20 patients. Each patient will receive postoperative bilateral TAP blocks (20mL of ropivacaine) and 1mL of normal saline bilaterally (control) with standard intrathecal bupivacaine and morphine. 2mg Dexamethasone Morphine 20 patients. Each patient will receive postoperative bilateral TAP blocks (20mL of 0.5% ropivacaine) with 0.5 mL (2mg) of dexamethasone and 0.5 ml of normal saline split between 2 sides with standard intrathecal bupivacaine and morphine. 2mg Dexamethasone Bupivacaine Hydrochloride 20 patients. Each patient will receive postoperative bilateral TAP blocks (20mL of 0.5% ropivacaine) with 0.5 mL (2mg) of dexamethasone and 0.5 ml of normal saline split between 2 sides with standard intrathecal bupivacaine and morphine. 4mg Dexamethasone Bupivacaine Hydrochloride 20 patients. Each patient will receive postoperative bilateral TAP blocks (20mL of 0.5% ropivacaine) with 20mL of 0.5% ropivacaine) and 1 mL (4mg) of dexamethasone between 2 sides with standard intrathecal bupivacaine and morphine. 4mg Dexamethasone Morphine 20 patients. Each patient will receive postoperative bilateral TAP blocks (20mL of 0.5% ropivacaine) with 20mL of 0.5% ropivacaine) and 1 mL (4mg) of dexamethasone between 2 sides with standard intrathecal bupivacaine and morphine.
- Primary Outcome Measures
Name Time Method Average Pain Score 48 hours postoperatively Average pain score (VAS) 48 hrs postoperatively between the study group and the control. The visual analog scale (VAS) is a validated, subjective measure for acute and chronic pain. 0 represents no pain, whereas 10 represents unbearable pain.
- Secondary Outcome Measures
Name Time Method Average Opioid Consumption from the time of delivery to 48hrs postoperatively Average opioid consumption 48 hrs postoperatively between the study group and the control
First Post-Operative Opioid Administration baseline to 48 hrs postoperatively Time until first dose post-operative opioid administration between the study group and the control
Trial Locations
- Locations (1)
UAB Department of Anesthesiology and Perioperative Medicine
🇺🇸Birmingham, Alabama, United States