Dose Escalation of Dexamethasone to Increase Duration of Transversus Abdominal Plane Block Following Cesarean Section

Dose Escalation of Dexamethasone to Increase Duration of Transversus Abdominal Plane Block Following Cesarean Section: A Prospective Randomized Double-Blinded Clinical Study

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.

Study Overview

• Status: Terminated
• Conditions: Post Surgical Pain
• Intervention / Treatment: Drug: Morphine; Drug: Ropivacaine (TAP blocks); Drug: Bupivacaine Hydrochloride; Drug: Normal saline 1ml; Drug: 2mg Dexamethasone; Drug: Normal saline 0.5ml; Drug: 4mg Dexamethasone

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.

• Study Type: Interventional
• Enrollment (Actual): 29
• Phase: Phase 2; Phase 3

Contacts and Locations

Study Locations

• United States
  • Alabama
    • Birmingham, Alabama, United States, 35249
      • UAB Department of Anesthesiology and Perioperative Medicine

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: Female

Description

Inclusion Criteria:

1. Women undergoing cesarean section delivery.

2. Patients classified as American Society of Anesthesiology (ASA) class II or III.

   1. ASA II: mild systemic disease, pregnancy
   2. ASA III: severe systemic disease
3. Women ≥ 18 years old
4. Neuraxial anesthesia (spinal) to be used as anesthetic technique intraoperatively for cesarean section (this is the UAB Anesthesiology standard of care).

Exclusion Criteria:

1. Any patient not classified as an ASA I or II.
2. General Anesthesia or neuraxial anesthesia with epidural used as anesthetic techniques for cesarean section.
3. Allergy/intolerance to local anesthetic or steroids.
4. Pre-existing neurological and/or anatomical deficit that would preclude regional block.
5. Coexisting coagulopathy such as hemophilia or von Willebrand Disease
6. BMI > 40.
7. Emergency Cesarean Sections

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Placebo Comparator: Control Group; 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.	Drug: Morphine; Drug: Ropivacaine (TAP blocks); 20mL of 0% ropivacaine with 20mL of 0.5% ropivacaine; Drug: Bupivacaine Hydrochloride; Drug: Normal saline 1ml; 1.0 ml of normal saline split between 2 sites with standard intrathecal bupivacaine and morphine
Active Comparator: 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.	Drug: Morphine; Drug: Ropivacaine (TAP blocks); 20mL of 0% ropivacaine with 20mL of 0.5% ropivacaine; Drug: Bupivacaine Hydrochloride; Drug: 2mg Dexamethasone; 0.5 mL (2mg) of dexamethasone and 0.5 ml of normal saline; Other Names: Baycadron, Maxidex, Decadron; Drug: Normal saline 0.5ml; 0.5 ml of normal saline split between 2 sites with standard intrathecal bupivacaine and morphine
Active Comparator: 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.	Drug: Morphine; Drug: Ropivacaine (TAP blocks); 20mL of 0% ropivacaine with 20mL of 0.5% ropivacaine; Drug: Bupivacaine Hydrochloride; Drug: 4mg Dexamethasone; 1 mL (4mg) of dexamethasone; Other Names: Baycadron, Maxidex, Decadron

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Average Pain Score	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.	48 hours postoperatively

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
First Post-Operative Opioid Administration	Time until first dose post-operative opioid administration between the study group and the control	baseline to 48 hrs postoperatively
Average Opioid Consumption	Average opioid consumption 48 hrs postoperatively between the study group and the control	from the time of delivery to 48hrs postoperatively

Collaborators and Investigators

• Sponsor: University of Alabama at Birmingham
• Investigators: Principal Investigator: Joel Feinstein, MD, Anesthesiology ad Perioperative Medicine

Study record dates

Study Major Dates

• Study Start (Actual): July 1, 2016
• Primary Completion (Actual): May 20, 2021
• Study Completion (Actual): May 20, 2021

Study Registration Dates

• First Submitted: March 13, 2017
• First Submitted That Met QC Criteria: March 30, 2017
• First Posted (Actual): March 31, 2017

Study Record Updates

• Last Update Posted (Actual): June 18, 2021
• Last Update Submitted That Met QC Criteria: May 23, 2021
• Last Verified: May 1, 2021

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Pathologic Processes; Postoperative Complications; Pain; Neurologic Manifestations; Pain, Postoperative; Physiological Effects of Drugs; Molecular Mechanisms of Pharmacological Action; Central Nervous System Depressants; Autonomic Agents; Peripheral Nervous System Agents; Enzyme Inhibitors; Analgesics; Sensory System Agents; Anesthetics; Anti-Inflammatory Agents; Antineoplastic Agents; Antiemetics; Gastrointestinal Agents; Glucocorticoids; Hormones; Hormones, Hormone Substitutes, and Hormone Antagonists; Antineoplastic Agents, Hormonal; Protease Inhibitors; Analgesics, Opioid; Narcotics; Anesthetics, Local; Dexamethasone; Dexamethasone acetate; BB 1101; Bupivacaine; Ropivacaine; Morphine
• Other Study ID Numbers: F160421006

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: No

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No