Spinal-Epidural Analgesia for Labor Pain

Recruiting in Palo Alto (17 mi)

Overseen byMrinalini Balki, MD

Age: 18 - 65

Sex: Female

Travel: May Be Covered

Time Reimbursement: Varies

Trial Phase: Academic

Waitlist Available

Sponsor: Samuel Lunenfeld Research Institute, Mount Sinai Hospital

No Placebo Group

Approved in 3 Jurisdictions

Trial Summary

What is the purpose of this trial?

Combined spinal-epidural (CSE) for labor analgesia has been used for many years and is practiced commonly at our institution, especially when the patient requests immediate pain relief. CSE is not only beneficial for its faster onset of analgesia, but also it is favorable in relation to the need for rescue analgesia, urinary retention, and rate of instrumental delivery compared to the traditional epidural. Despite its beneficial effects, there is a risk of about 15-30% of developing abnormal fetal heart rate following CSE. This is self-resolving with minimal or no intervention. Although the cause of fetal bradycardia is not fully elucidated, variations in uterine artery blood flow after epidural analgesia are thought to be due to the interaction of numerous events related to blockade of sympathetic innervations, fluid administration, maternal hypotension, uterine vascular effects of sympathetic block, fluctuations in circulating catecholamines, and possibly the effect of opioids. Similar mechanism is thought to be a cause of fetal bradycardia after the CSE with its faster onset and superior block. Maternal or fetal circulation during labor can be assessed using continuous-wave Doppler ultrasound to monitor maternal uterine artery (UtA) and fetal umbilical artery (UmA) velocity waveforms to detect changes in blood flow. The velocimetry indices mentioned above have been often used to assess the changes in the blood flow before and after the induction of epidural analgesia during labor in several studies. Although there are some studies regarding the effect of labor epidural analgesia using velocimetry indices, but there is currently no published study evaluating velocimetry indices of uterine and umbilical arteries before and after the induction of CSE. Thus, the aim of this study is to investigate the impact of CSE to maternal and fetal blood flow to evaluate the relationships. The investigators hypothesize that both uterine artery and umbilical artery blood flow are reduced after the induction of CSE, which may be responsible for the occurrence of fetal bradycardia.

Research Team

Mrinalini Balki, MD

Principal Investigator

MOUNT SINAI HOSPITAL

Eligibility Criteria

This trial is for term pregnant women in active labor who want pain relief and have no prior fetal complications or spinal issues. They must consent to the study, have a single pregnancy without congenital anomalies, be relatively healthy (ASA<4), and not severely overweight (BMI under 50 kg/m2).

Inclusion Criteria

Pregnant patients close to giving birth who want pain relief during labor.

The unborn baby does not show any signs of birth defects, trouble, or slowing down before the CSE.

My health is stable enough for surgery.

See 3 more

Exclusion Criteria

I have a known spinal deformity.

Refusal to consent for the study

I have had surgery on my back involving metal rods or screws.

See 1 more

Treatment Details

Interventions

Combined Spinal-epidural Analgesia (Procedure)

Trial OverviewThe study tests how combined spinal-epidural analgesia affects blood flow in maternal uterine and fetal umbilical arteries during labor. It uses Doppler ultrasound to monitor changes before and after CSE administration, aiming to understand its link with fetal bradycardia.

Participant Groups

1Treatment groups

Experimental Treatment

Group I: UltrasoundExperimental Treatment1 Intervention

Ultrasound will be used to measure velocimetric indices of both right and left uterine arteries and umbilical artery.

Combined Spinal-epidural Analgesia is already approved in Canada for the following indications: