Ketamine Versus Fentanyl for Surgical Abortions

Phase 4

Completed

Conditions: Abortion in First Trimester
Pain, Procedural
Opioid Use

Interventions: Drug: Ketamine
Drug: Fentanyl

Registration Number: NCT04871425

Lead Sponsor: University of Washington

Brief Summary: Ketamine is commonly used for procedural sedation and analgesia. It is widely used for trauma cases in the emergency department and is considered a superior agent in the outpatient setting due to its lack of respiratory and cardiovascular depression. In chronic opioid users, ketamine decreases acute pain and reduces postoperative opioid consumption. Few studies have examined the use of ketamine for surgical abortions. Previous studies found significant rates of emergence phenomena; however, this can be prevented if a benzodiazepine is given at the same time. Ketamine deserves further study to determine whether it is an acceptable alternative to a standard opioid-based regimen for surgical abortion. Our primary objective is to compare patient satisfaction after surgical abortion among patients receiving IV ketamine versus IV fentanyl for procedural sedation. Our secondary objectives include postoperative pain, additional pain medication used, and postoperative opioid use after the procedure. Our hypothesis is that ketamine will provide similar patient satisfaction and reduce postoperative opioid use. This will be a randomized controlled noninferiority clinical trial of 84 women receiving either IV ketamine with IV midazolam or IV fentanyl with IV midazolam for outpatient one day surgical abortions up to 13, 6/7 weeks gestation. Both groups will receive a standardized paracervical block and additional pain medication as needed. Our study has the potential to introduce IV ketamine as a satisfactory medication for outpatient surgical abortions. Ketamine may decrease the need for IV fentanyl, reduce postoperative opioid use, and may prove to be a superior analgesic for chronic opioid users.

Detailed Description: First-trimester surgical abortions are one of the most common outpatient procedures worldwide. Although abortion is a quick procedure, most patients still report at least moderate pain.1 Most providers use a paracervical block plus intravenous (IV) moderate sedation with fentanyl (38%) or oral medication (33%). A recent trial comparing IV fentanyl to placebo among participants who also received the paracervical block found a 1-point difference in pain on an 11-point scale. The authors questioned the benefit of this reduction in pain in light of fentanyl's various side effects including nausea and drowsiness, the requirement for additional monitoring and resuscitative equipment, and need for naloxone in case of overdose.

Due to our nation's opioid crisis, there has been growing interest in identifying a non-opioid medication to provide safe, short term, satisfactory pain control during first trimester outpatient surgical abortions. Ketamine is commonly used for procedural sedation and analgesia, and it also reduces postoperative pain. It acts primarily as an N-methyl-D-aspartate receptor antagonist but has some opioid receptor activity. It is widely used for trauma cases and acute pain crises, and is considered a superior agent in the outpatient setting due to its lack of respiratory and cardiovascular depression. Few studies have examined ketamine for surgical abortions. Most studies found improvement when compared to the paracervical block or remifentanil. Our study's primary outcome was to determine if ketamine was noninferior in terms of patient satisfaction with anesthesia to fentanyl for procedural sedation for outpatient first trimester surgical abortions.

Recruitment & Eligibility

Status: COMPLETED

Sex: Female

Target Recruitment: 110

Inclusion Criteria

Aged 14 years or older
Voluntarily requesting surgical pregnancy termination
Intrauterine pregnancy up to 13 weeks 6 days by transabdominal or transvaginal ultrasound performed on day of procedure
Eligible for suction curettage
English or Spanish speaking
Able and willing to give informed consent and agree to terms of the study

Exclusion Criteria

Age less than 14 years
Reaspiration procedure or failed medication abortion
Early pregnancy loss
Alcohol use disorder or acute alcohol intoxication
Currently incarcerated
Gestational age 14 weeks or more
Requesting a specific pain regimen
Premedication with misoprostol
Contraindications or allergies to ketamine or fentanyl

Study & Design

Study Type: INTERVENTIONAL

Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Ketamine	Ketamine	Participant will receive 2mg IV midazolam and 0.2-0.5mg/kg IV ketamine over 2 minutes, which can be repeated q5 minutes until appropriate analgesia is achieved.
Fentanyl	Fentanyl	Participant will receive 2mg IV midazolam and 0.5-1mcg/kg IV fentanyl over 2 minutes, which can be repeated q5m until appropriate analgesia is achieved.

Primary Outcome Measures

Name	Time	Method
Satisfaction With Anesthesia Assessed by the ISAS	At discharge or 30 minutes after the procedure	After the procedure, either at time of discharge (if less than 30 minutes) or at 30 minutes (if not yet discharged), research personnel will assess the participant's satisfaction with anesthesia using the Iowa Satisfaction with Anesthesia Scale. This is a validated perioperative anesthesia satisfaction scale with a minimum score of -3 and a maximum score of +3 with higher scores indicating higher satisfaction.

Secondary Outcome Measures

Name	Time	Method
Provider Satisfaction With Anesthesia Assessed by the VAS	Immediately postoperatively	After the procedure, research personnel will assess provider's satisfaction with patient's anesthesia on a 100mm visual analog scale. The minimum score is 0mm and the maximum score if 100mm, with higher scores indicating higher satisfaction.
Number of Participants Administered Additional Pain Medications	Immediately postoperatively	After the procedure, research personnel will ask anesthetist what medications, if any, they gave outside of the study protocol
Postoperative Pain Assessed by the VAS	24 hours postoperatively and 7 days postoperatively	Patients will complete 2 followup surveys asking about their postoperative pain after discharge. This will be assessed on a 100mm visual analog scale. The minimum score is 0mm and the maximum score if 100mm, with higher scores indicating higher pain levels.