Maternal Microcirculation & SDF Imaging

IWK Health Centre

Status and phase: Completed; Phase 4

Conditions: Pregnancy

Treatments: Drug: Spinal Anesthesia- Bupivacaine; Device: Initial MicroScan® (Microvision Medical) SDF Measurement; Drug: Phenylephrine Infusion; Device: Comparative MicroScan® (Microvision Medical) SDF Measurement; Drug: Bolus Phenylephrine/Ephedrine Treatment

Study type: Interventional

Funder types: Other

Identifiers

NCT02376192

IWK1010276

Details and patient eligibility

About

This is a study of pregnant women undergoing a cesarean delivery. It will compare their microcirculation before and after the anesthetic. Microcirculation means blood flow to the extremely small blood vessels in the body. It will also look at the differences in microcirculation of participants who receive an infusion of phenylephrine compared to participants who don't. The investigators hypothesize that spinal anesthesia will reduce the vascular density and proportion of perfused vessels.

Enrollment: 32 patients

Sex: Female

Ages: 18 to 45 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• American Society of Anesthesiologists (ASA) Physical Status I-II (ASA I - Healthy, ASA II - mild and controlled systemic disease)
• Singleton pregnancies
• 36-42 weeks gestation
• Non-labouring
• Scheduled cesarean delivery
• English speaking
• Age 18-45 years

Exclusion criteria

• Cardiovascular disease
• Hypertensive disease of pregnancy (i.e. mild & severe preeclampsia)
• Allergy to phenylephrine, or any other standardized medication
• Obesity (BMI > 35 kg/m2)
• Diabetes Mellitus type 1
• Smoker
• Coffee/Caffeine intake within 6 hours of SDF measurement

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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32 participants in 2 patient groups

Bolus Phenylephrine/Ephedrine Treatment'

Experimental group

Description:

Initial MicroScan® (Microvision Medical) SDF measurement are recorded in the obstetric preoperative area within two hours prior to administration of spinal anesthesia. In the operating room participants will receive a standard spinal anesthetic (hyperbaric bupivacaine, fentanyl and preservative free morphine) followed by a second comparative MicroScan® (Microvision Medical) SDF measurement within 10 minutes of initiation of spinal anesthetic. Participants who experience hypotension will receive bolus phenylephrine and/or ephedrine treatment as needed.

Treatment:

Drug: Bolus Phenylephrine/Ephedrine Treatment

Device: Comparative MicroScan® (Microvision Medical) SDF Measurement

Drug: Spinal Anesthesia- Bupivacaine

Device: Initial MicroScan® (Microvision Medical) SDF Measurement

Phenylephrine Infusion Group

Experimental group

Description:

Initial MicroScan® (Microvision Medical) SDF measurement are recorded in the obstetric preoperative area within two hours prior to administration of spinal anesthesia. In the operating room participants will receive a standard spinal anesthetic (hyperbaric bupivacaine, fentanyl and preservative free morphine) followed by a second comparative MicroScan® (Microvision Medical) SDF measurement within 10 minutes of initiation of spinal anesthetic. Participants will have an infusion of phenylephrine started immediately following the induction of spinal anesthesia for prevention of hypotension.

Treatment:

Drug: Phenylephrine Infusion

Device: Comparative MicroScan® (Microvision Medical) SDF Measurement

Drug: Spinal Anesthesia- Bupivacaine

Device: Initial MicroScan® (Microvision Medical) SDF Measurement