Changes in Velocimetric Indices of Uterine and Umbilical Arteries Before and After Combined Spinal-epidural Analgesia in Laboring Women
- Conditions
- Labor Pain
- Interventions
- Device: Ultrasound
- Registration Number
- NCT05512065
- Lead Sponsor
- Samuel Lunenfeld Research Institute, Mount Sinai Hospital
- Brief Summary
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.
- Detailed Description
Not available
Recruitment & Eligibility
- Status
- COMPLETED
- Sex
- Female
- Target Recruitment
- 30
- Written informed consent
- Term pregnant patients requesting labor analgesia
- Singleton pregnancy
- Term pregnant patients in active labor
- ASA<4
- No evidence of fetal congenital anomalies, fetal compromise or fetal decelerations prior to CSE
- Refusal to consent for the study
- Known spinal deformities
- Previous back instrumentation
- Patients with BMI>50 kg/㎡ due to anticipated technical challenges in Doppler studies
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- SINGLE_GROUP
- Arm && Interventions
Group Intervention Description Ultrasound Ultrasound Ultrasound will be used to measure velocimetric indices of both right and left uterine arteries and umbilical artery.
- Primary Outcome Measures
Name Time Method Uterine artery velocimetric index - pulsatility index (PI) at 30 minutes 5 minutes Uterine artery velocimetric index - pulsatility index (PI) will be measured 30 minutes after combined spinal epidural
Umbilical artery velocimetric index - systolic/diastolic ratio (S/D) at 10 minutes 5 minutes Umbilical artery velocimetric index - systolic/diastolic ratio (S/D) will be measured 10 minutes after combined spinal epidural
Umbilical artery velocimetric index - pulsatility index (PI) at baseline 5 minutes Umbilical artery velocimetric index - pulsatility index (PI) will be measured at baseline (prior to combined spinal epidural).
Umbilical artery velocimetric index - pulsatility index (PI) at 10 minutes 5 minutes Umbilical artery velocimetric index - pulsatility index (PI) will be measured 10 minutes after combined spinal epidural
Umbilical artery velocimetric index - systolic/diastolic ratio (S/D) at baseline 5 minutes Umbilical artery velocimetric index - systolic/diastolic ratio (S/D) will be measured at baseline (prior to combined spinal epidural).
Umbilical artery velocimetric index - systolic/diastolic ratio (S/D) at 30 minutes 5 minutes Umbilical artery velocimetric index - systolic/diastolic ratio (S/D) will be measured 30 minutes after combined spinal epidural
Umbilical artery velocimetric index - resistance index (PI) at baseline 5 minutes Umbilical artery velocimetric index - resistance index (PI) will be measured at baseline (prior to combined spinal epidural).
Uterine artery velocimetric index - systolic/diastolic ratio (S/D) at baseline 5 minutes Uterine artery velocimetric index - systolic/diastolic ratio (S/D) will be measured at baseline (prior to combined spinal epidural).
Uterine artery velocimetric index - systolic/diastolic ratio (S/D) at 10 minutes 5 minutes Uterine artery velocimetric index - systolic/diastolic ratio (S/D) will be measured 10 minutes after combined spinal epidural
Uterine artery velocimetric index - systolic/diastolic ratio (S/D) at 30 minutes 5 minutes Uterine artery velocimetric index - systolic/diastolic ratio (S/D) will be measured 30 minutes after combined spinal epidural
Uterine artery velocimetric index - pulsatility index (PI) at baseline 5 minutes Uterine artery velocimetric index - pulsatility index (PI) will be measured at baseline (prior to combined spinal epidural).
Uterine artery velocimetric index - resistance index (RI) at baseline 5 minutes Uterine artery velocimetric index - resistance index (PI) will be measured at baseline (prior to combined spinal epidural).
Umbilical artery velocimetric index - pulsatility index (PI) at 30 minutes 5 minutes Umbilical artery velocimetric index - pulsatility index (PI) will be measured 30 minutes after combined spinal epidural
Uterine artery velocimetric index - pulsatility index (PI) at 10 minutes 5 minutes Uterine artery velocimetric index - pulsatility index (PI) will be measured 10 minutes after combined spinal epidural
Uterine artery velocimetric index - resistance index (RI) at 10 minutes 5 minutes Uterine artery velocimetric index - resistance index (PI) will be measured 10 minutes after combined spinal epidural
Uterine artery velocimetric index - resistance index (RI) at 30 minutes 5 minutes Uterine artery velocimetric index - resistance index (PI) will be measured 30 minutes after combined spinal epidural
Umbilical artery velocimetric index - resistance index (PI) at 30 minutes 5 minutes Umbilical artery velocimetric index - resistance index (PI) will be measured 30 minutes after combined spinal epidural
Umbilical artery velocimetric index - resistance index (PI) at 10 minutes 5 minutes Umbilical artery velocimetric index - resistance index (PI) will be measured 10 minutes after combined spinal epidural
- Secondary Outcome Measures
Name Time Method Apgar score at 1 minute 1 minute Apgar score at 1 minute
Pain score at 10 min - questionnaire 1 minute Pain score - verbal numeric rating scale (0-10) at 10 min after combined spinal epidural
presence of fetal bradycardia - questionnaire up to 24 hours presence of fetal bradycardia (fetal heart rate \<110)
Apgar score at 5 minutes 5 minute2 Apgar score at 5 minutes
Hypotension: systolic blood pressure less than 80% of baseline 30 minutes Systolic blood pressure \< 80% of baseline, monitored q5 for 30 minutes following combined spinal epidural
Sensory block level at 10 minutes 10 minutes Sensory block level at 10 minutes following combined spinal epidural
fetal heart rate at baseline 5 minutes fetal heart rate at baseline, prior to combined spinal epidural
Pain score at baseline - questionnaire 1 minute Pain score - verbal numeric rating scale (0-10) prior to combined spinal epidural
Hypertension: systolic blood pressure greater than 120% of baseline 30 minutes Systolic blood pressure \> 120% of baseline, monitored q5 for 30 minutes following combined spinal epidural
Sensory block level at 30 minutes 30 minutes Sensory block level at 30 minutes following combined spinal epidural
Duration of labour up to 24 hours Onset of labour until delivery of the placenta
fetal heart rate q5 min up to 30 minutes 30 minutes fetal heart rate q5 min up to 30 minutes following combined spinal epidural
Pain score at 30 min - questionnaire 1 minute Pain score - verbal numeric rating scale (0-10) at 30 min after combined spinal epidural
Desaturation: oxygen level <95% 30 minutes Oxygen level \<95%, monitored q5 for 30 minutes following combined spinal epidural
Presence of hypertonic uterine contractions up to 24 hours Presence of hypertonic uterine contractions as noted by the nursing or obstetric team.
Neonatal weight 2 minutes Neonatal weight measured after delivery in grams
Bradycardia: heart rate less than 70% of baseline 30 minutes Heart rate \< 70% of baseline or a heart rate \< 50bpm, monitored q5 for 30 minutes following combined spinal epidural
Type of delivery up to 24 hours Type of delivery will be recorded: vaginal, cesarean section, instrumental delivery
presence of fetal tachycardia - questionnaire up to 24 hours presence of fetal tachycardia (fetal heart rate \>160)
Trial Locations
- Locations (1)
Mount Sinai Hospital
🇨🇦Toronto, Ontario, Canada