Anesthesia, Blood Loss
Conditions
Keywords
Sevoflurane, anesthesia, abortion, blood loss
Brief summary
Sevoflurane is an FDA-approved anesthetic drug commonly used for anesthesia during second trimester abortion procedures. It has a few advantages, including ease of use by the anesthesia provider. However, the literature suggests that when used in doses higher than those used at Oregon Health & Science University (OHSU) and Lovejoy, it is associated with an increase in the risk of bleeding. The investigators study aims to test whether the lower dose used at OHSU and Lovejoy during second trimester abortion procedures causes any difference in blood loss, when compared to similar abortion procedures for which this drug is not used.
Detailed description
This study seeks to examine the bleeding complications associated with use of sevoflurane in general anesthesia regimens for second trimester abortion procedures and assess anesthesia providers' use and beliefs regarding possible risks associated with newer inhalational agents such as sevoflurane in this setting. Participants' anesthesia will either be intravenous (IV) propofol, IV midazolam, IV fentanyl and nitrous oxide or this same regimen combined with sevoflurane during maintenance of anesthesia. Procedural outcomes, specifically those related to bleeding complications, including need to intervene for excess blood loss, will be recorded and analyzed to establish if such a relationship between use of sevoflurane and excess blood loss exists.
Interventions
DRUGSevoflurane
Subject receives Sevoflurane in addition to other standard of care drug regimens for anesthesia with this procedure.
OTHERNo Sevoflurane
Subject only standard of care drug regimens for anesthesia with this procedure.
Sponsors
Oregon Health and Science University
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
SUPPORTIVE_CARE
Masking
DOUBLE (Subject, Investigator)
Eligibility
Sex/Gender
FEMALE
Age
18 Years to 50 Years
Healthy volunteers
Yes
Inclusion criteria
* Voluntarily requesting pregnancy termination * Estimated gestational age of 18 weeks - 23 weeks, 6 days gestational age as calculated by fetal biparietal diameter on clinic ultrasound. * Be able and willing to sign an informed consent and agree to terms of the study
Exclusion criteria
* Known severe maternal respiratory disease or upper respiratory infection or sinus blockage * Anticoagulation use: within 24 hours if Lovenox, or within 12 hours if heparin, (Must have a documented normal international normalized ratio (INR) prior to procedure if on anticoagulation) * Multiple pregnancy * Fetal demise, if more than 2 weeks difference exists between known gestational age (by previous US dating) and gestational size on current ultrasound. * Known allergy/sensitivity to sevoflurane or any other inhaled anesthetic agents
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Number of Participants Needing Intervention to Treat Blood Loss (a Composite of Use of Uterotonics, Re-aspiration, and Bimanual Massage) | At time of uterine evacuation and immediately post-operatively, an average of 7.1 minutes | Provider report for need to intervene due to blood loss (yes/no) |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Number of Participants With Estimated Blood Loss Greater Than 300 mL (Yes/no) | At time of uterine evacuation, an average of 7.1 minutes | Procedural blood loss greater than 300 mL. Blood loss was measured in a standardized fashion (amniotic fluid was discarded, blood was separated from tissue, and all gauze surgical drapes weighed). |
| Procedure Time: T-test (Time of Speculum Placement to Time Speculum Removed) | Time of speculum place to time of speculum removal, an average of 7.1 minutes | Length of procedure from time of speculum placement to time of speculum removal, in minutes. |
| Number of Participants Experiencing Side Effects (Nausea, Dizziness) | Post-procedure, within 30 minutes | — |
| Patient and Provider Satisfaction With Anesthesia | Post-procedure, within 30 minutes | Scores reported on 10-cm Visual Analog Scale (VAS anchors: 0= not satisfied at all, 10= completely satisfied) . Reported as mean +/- standard deviation. Subjects and providers were blinded to anesthesia method. Subjects and providers completed post-operative questionnaire within 30 minutes of procedure completion. |
Countries
United States
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| Sevoflurane Subject receives Sevoflurane in addition to other standard of care drug regimens for anesthesia with this procedure.
Sevoflurane: Subject receives Sevoflurane in addition to other standard of care drug regimens for anesthesia with this procedure. | 80 |
| No Sevoflurane Subject receives standard of care drug regimens for anesthesia with this procedure.
No Sevoflurane: Subject only standard of care drug regimens for anesthesia with this procedure. | 80 |
| Total | 160 |
Baseline characteristics
| Characteristic | Sevoflurane | No Sevoflurane | Total |
|---|---|---|---|
| Age, Continuous | 25.9 years STANDARD_DEVIATION 6.2 | 25.9 years STANDARD_DEVIATION 5.9 | 25.9 years STANDARD_DEVIATION 6 |
| Region of Enrollment United States | 80 participants | 80 participants | 160 participants |
| Sex: Female, Male Female | 80 Participants | 80 Participants | 160 Participants |
| Sex: Female, Male Male | 0 Participants | 0 Participants | 0 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | — / — | — / — |
| other Total, other adverse events | 3 / 80 | 1 / 80 |
| serious Total, serious adverse events | 1 / 80 | 0 / 80 |
Outcome results
Primary
Number of Participants Needing Intervention to Treat Blood Loss (a Composite of Use of Uterotonics, Re-aspiration, and Bimanual Massage)
Provider report for need to intervene due to blood loss (yes/no)
Time frame: At time of uterine evacuation and immediately post-operatively, an average of 7.1 minutes
| Arm | Measure | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|
| Sevoflurane | Number of Participants Needing Intervention to Treat Blood Loss (a Composite of Use of Uterotonics, Re-aspiration, and Bimanual Massage) | 20 Participants |
| No Sevoflurane | Number of Participants Needing Intervention to Treat Blood Loss (a Composite of Use of Uterotonics, Re-aspiration, and Bimanual Massage) | 13 Participants |
Secondary
Number of Participants Experiencing Side Effects (Nausea, Dizziness)
Time frame: Post-procedure, within 30 minutes
| Arm | Measure | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|
| Sevoflurane | Number of Participants Experiencing Side Effects (Nausea, Dizziness) | 13 Participants |
| No Sevoflurane | Number of Participants Experiencing Side Effects (Nausea, Dizziness) | 11 Participants |
Secondary
Number of Participants With Estimated Blood Loss Greater Than 300 mL (Yes/no)
Procedural blood loss greater than 300 mL. Blood loss was measured in a standardized fashion (amniotic fluid was discarded, blood was separated from tissue, and all gauze surgical drapes weighed).
Time frame: At time of uterine evacuation, an average of 7.1 minutes
| Arm | Measure | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|
| Sevoflurane | Number of Participants With Estimated Blood Loss Greater Than 300 mL (Yes/no) | 12 Participants |
| No Sevoflurane | Number of Participants With Estimated Blood Loss Greater Than 300 mL (Yes/no) | 6 Participants |
Secondary
Patient and Provider Satisfaction With Anesthesia
Scores reported on 10-cm Visual Analog Scale (VAS anchors: 0= not satisfied at all, 10= completely satisfied) . Reported as mean +/- standard deviation. Subjects and providers were blinded to anesthesia method. Subjects and providers completed post-operative questionnaire within 30 minutes of procedure completion.
Time frame: Post-procedure, within 30 minutes
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Sevoflurane | Patient and Provider Satisfaction With Anesthesia | Provider Satisfaction | 9.4 cm | Standard Deviation 1.1 |
| Sevoflurane | Patient and Provider Satisfaction With Anesthesia | Patient Satisfaction | 8.4 cm | Standard Deviation 1.5 |
| No Sevoflurane | Patient and Provider Satisfaction With Anesthesia | Provider Satisfaction | 9.3 cm | Standard Deviation 1.4 |
| No Sevoflurane | Patient and Provider Satisfaction With Anesthesia | Patient Satisfaction | 8.2 cm | Standard Deviation 1.5 |
Secondary
Procedure Time: T-test (Time of Speculum Placement to Time Speculum Removed)
Length of procedure from time of speculum placement to time of speculum removal, in minutes.
Time frame: Time of speculum place to time of speculum removal, an average of 7.1 minutes
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Sevoflurane | Procedure Time: T-test (Time of Speculum Placement to Time Speculum Removed) | 7.0 minutes | Standard Deviation 3.7 |
| No Sevoflurane | Procedure Time: T-test (Time of Speculum Placement to Time Speculum Removed) | 7.3 minutes | Standard Deviation 3.3 |