Labor Pain Clinical Trials in Canada

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. Read Less

Epidural analgesia was introduced to the world of obstetrics in 1909 by Walter Stoeckel. Over the following 100 years it has developed to become the gold-standard for delivery of intra-partum analgesia, with between 60 and 75% of North American parturients receiving an epidural during their labor. Effective labor analgesia has been shown to improve maternal and fetal outcomes. One aspect of catheter insertion that has not been fully evaluated, and with very little recent work undertaken, is the optimal length of epidural catheter to be left in the epidural space. Dislodgement or displacement of epidural catheter remains a significant cause for failure with analgesia. Novel methods of fixation may further reduce the risk of catheter migration. Another factor is the direction of travel within the epidural space, only 13% of lumbar catheters remain uncoiled after insertion of more than 4 cm into the epidural space. Hypothesis: The investigators hypothesize that catheters inserted to 4 cm will have a lower rate of failure when compared to those inserted to 5 cm. Objective: This study aims to evaluate the difference in quality of labor analgesia delivered by epidural catheters inserted to either 4 or 5 cm into the epidural space. This study will be conducted as an interventional double-blinded randomised control trial to establish best practice. Read Less

Neuraxial analgesia has shown to be the gold standard for effective labor pain relief, offering numerous benefits including enhanced pain control and maternal satisfaction. The methods to achieve neuraxial analgesia include lumbar epidural (LE), and combined spinal epidural (CSE). While LE may not consistently provide optimal pain relief, leading to frequent maternal requests for supplemental analgesics, CSE presents a promising advancement. This is due to the rapid onset of pain relief from intrathecal components, complemented by the longer-lasting effects of epidural medications. Intrathecal drugs have demonstrated the ability to offer more symmetrical blockades compared to epidurally administered medications. Nonetheless, some clinicians remain cautious about CSE due to the potential for increased pain when transitioning from spinal to less effective epidural analgesia. Long-acting opioids like morphine in the intrathecal space may mitigate this problem by providing transitional analgesia to the laboring parturient. The primary aim of this randomized controlled trial is to provide evidence of whether the addition of 100 mcg of morphine in the intrathecal (spinal) component of CSE reduces the rate of breakthrough pain during labor. Read Less

The purpose of this prospective randomized controlled study is to compare the number of physician top-up interventions during the first stage of labour between two different neuraxial analgesia techniques : the dural puncture epidural and the standard epidural. Read Less

This study aims to establish if programmed intermittent epidural bolus combined to patient controlled analgesia in labour analgesia will lower the hourly bupivacaine consumption when compared to continuous infusion combined with patient controlled analgesia. The investigators' hypothesis is that the use of programmed intermittent epidural bolus will lower the hourly bupivacaine consumption. Read Less