Clinical trials

Cesarean section under general anesthesia requires intubation (insertion of a tube through the mouth into the breathing pipe to support breathing during the surgery). A device called a video laryngoscope is used, which has a smooth, curved, or less curved component called 'a blade' that helps the doctor gently see the voice box and guide the breathing tube safely into place during anesthesia; it is not a sharp tool blade. There are two types of video laryngoscopes blades: a Macintosh- style blade with a gentle curve, approximately 90 degrees) and a hyperangulated blade (with a more pronounced curve). Although video laryngoscopes are safe and both types have been used for around 20 years, it is not known whether one type works better that the other in patients undergoing cesarean delivery under general anesthesia. Because general anesthesia is used in only a small proportion (about 5%) of all cesarean deliveries, research in this area is limited. The main purpose of the study is to assess if a study comparing these two types of blades in the obstetric population is feasible. This is also known as a feasibility study, which aims to test the study plan and determine whether enough participants will join a larger study and accept the study procedures. The results will be used as a guide for a larger study.

Labour analgesia decisions are often made under time pressure, while in pain, which may lead patients to feel unprepared or uninformed. Shared decision-making (SDM) enhances patient satisfaction, promotes alignment with personal values, and improves trust in clinical care. Digital tools can support SDM by providing accessible, evidence-based information. The Society for Obstetric Anesthesia and Perinatology (SOAP) is an international organization made up of doctors who specialize in managing pain and anesthesia during pregnancy. Their focus is the wellbeing and safety of mothers and their babies from early pregnancy through delivery and recovery. The Painless Push digital resource educates mothers about ways to manage pain during labour. This trial aims to evaluate whether directing patients to access to the website https://thepainlesspush.com/ improves preparedness for shared decision-making compared to the current care, which is access to the Mount Sinai Obstetric Anesthesia website.

Postpartum hemorrhage (PPH) is a leading cause of maternal mortality, and its severity has been increasing globally, including in high-income countries. The most common cause of PPH is uterine atony occurring in about 70% of cases. Uterotonic agents, like oxytocin, are key in managing the third stage of labour to prevent PPH. Oxytocin is a short-acting medication and requires frequent dosing, however, carbetocin, a longer-acting analogue that can be administered as a single dose, provides sustained uterotonic activity. Calcium chloride is a readily available, inexpensive medication that has been studied as an adjunct to primary uterotonics due to its role in uterine contractility. A randomized trial found no overall reduction in blood loss with calcium chloride and oxytocin, but a subgroup analysis suggested it may reduce bleeding in cases of uterine atony. This study was conducted in the US where carbetocin is not readily available. The investigators propose a double-blind randomized trial investigating if co-administering calcium chloride with carbetocin during scheduled cesarean deliveries reduces PPH secondary to uterine atony.

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.

The goal of this study is to compare 2 medications that are commonly used to prevent excess uterine bleeding (postpartum hemorrhage, or PPH) following cesarean delivery (CD), oxytocin and carbetocin. Most of the trials evaluating the preventative role of oxytocin and carbetocin after CD have focused on patient with low-risk of PPH. This trial will focus on patients that are at increased risk of PPH, with risk factors such as: multiple gestation (twins, or more multiples), large baby, polyhydramnios (excess amniotic fluid), history of PPH, body mass index greater than 40, diabetes mellitus, hypertension, and placenta previa. The investigators hypothesize that carbetocin would be more effective than an oxytocin regimen in reducing the risk of PPH in patients undergoing CD with any of the biological high-risk factors.

This study will investigate the effects of drugs called "uterotonics" that help with the contraction of the uterus after a baby is born. This uterine contraction is very important to stop the bleeding after delivery. An uncontracted uterine state is called "uterine atony", which can lead to an excessive amount of post-delivery bleeding. Carbetocin is an uterotonic drug that works well to prevent post-delivery bleeding. In some cases, carbetocin is not enough to contract the uterus, and ongoing bleeding continues. When that happens, there are other uterotonic medications that can be used. In this study, we aim to find which uterotonic drug, amongst those available (oxytocin, carbetocin, ergometrine or carboprost), is more effective to lower the risk of post-delivery bleeding once carbetocin has already been administered. This study will be done by using a very small sample of uterine tissue, taken from the incision site, following delivery by cesarean section. The sample is taken to the laboratory and will be exposed to carbetocin followed by other uterotonic drugs. The information obtained from this study will help modify the treatment for uterine atony and post-delivery bleeding to lower the risk further.

The goal of this study is to learn about how medication that is used to help treat low blood pressure during a Cesarean delivery (CD) can cause changes to the uterine muscle tissue and its ability to contract, in patients with Type II and gestational diabetes. Spinal anesthesia administered during elective CD has been known to cause hypotension (low blood pressure) as a side effect during the procedure, and is prevented by administration of vasopressors (medication to raise blood pressure) by the anesthesiologist after the delivery of the baby. Vasopressors treat hypotension by interacting with receptors on blood vessels that increase blood pressure, which can also cause changes to uterine contractility. Inadequate uterine contraction after CD can expose mothers to postpartum hemorrhage (PPH), with diabetic patients displaying a 2.5-times higher risk of PPH. It is important to understand how vasopressor(s) might affect the uterine contractility of women with Type II and gestational diabetes. Since medication to contract the uterus is also routinely administered at delivery, it is important to study the effect of these drugs in combination. The purpose of this study is to compare uterine contractility patterns and receptor distribution in women with type II and gestational diabetic and control term pregnant patients with administration of vasopressors. This will be done using small uterine tissue samples taken from the incision site following CD, which will then be used for experiments in the laboratory.

This study is designed to determine the minimal effective oxytocin maintenance infusion required in labouring women undergoing cesarean delivery to achieve the best effect. Oxytocin is a drug that is routinely used to help the uterus to contract and keep it contracted after delivery. Consequently, it will help to reduce blood loss after delivery. In order to determine the minimal effective dose, the investigators will conduct a dose-finding study. The first patient will receive a set oxytocin infusion. The next patient's infusion dose of oxytocin, will either increase or decrease, depending on how the previous patient responds in terms of uterine tone. If the response is satisfactory with the infusion dose used, the next patient will either receive the same infusion dose or it will be decreased depending on a probability of 1:9. If the response is not satisfactory, then the infusion dose will increase for the next patient. The dose for each patient will be determined based on the results of the uterine contraction of the previous patient. The investigators hypothesize that the ED90 of the oxytocin infusion rate to maintain adequate uterine tone in labouring women with induced or augmented labour undergoing cesarean delivery, following an initial effective bolus dose, would be lower than 0.74 IU/min (44 IU/h), which was found as the ED90 in a previous study, without an initial bolus dose prior to the infusion.

Hypotension is one of the most common adverse effects of spinal anesthesia for cesarean deliveries, affecting as many as 55-90% of mothers. Hypotension during cesarean deliveries can have detrimental effects on the mother and neonate. Various vasopressors, such as ephedrine, phenylephrine and more recently norepinephrine, have been used for the prevention and treatment of hypotension at cesarean deliveries. Ephedrine was historically considered as the gold standard vasopressor for the management of hypotension during cesarean deliveries. This was based on studies in animal models that showed preserved uteroplacental circulation with ephedrine and not with phenylephrine. However, multiple studies in the past several decades have shown that phenylephrine compared with ephedrine results in a more favorable fetal acid-base status. Consequently, the use of phenylephrine for blood pressure management during cesarean deliveries increased. Recently, norepinephrine was introduced in the obstetrical practice for the management of hypotension at cesarean deliveries, due to its ability to maintain maternal cardiac output better than phenylephrine. Studies have also investigated the use of vasopressin to limit hypotension during CD. There have been case reports of successful vasopressin usage to treat post-spinal hypotension after CD in patients with advanced idiopathic pulmonary arterial hypertension as well as severe mitral stenosis with pulmonary hypertension. Its effect was associated with hemodynamic stability without evidence of harm to the mother or child. However, much controversy still exists surrounding the choice of vasopressor in the obstetric population, in large part due to their varying efficacies, and maternal and fetal effects. Vasopressors used for the treatment of hypotension during cesarean deliveries can have significant direct or indirect effects on the perfusion of uteroplacental and umbilical vessels. Reduction of uteroplacental perfusion and constriction of umbilical vessels can result in fetal acidosis, however, the mechanisms for these effects are unclear. The investigators hypothesize that ephedrine, phenylephrine and norepinephrine and vasopressin have variable effects on the contractility of pregnant myometrium and umbilical arteries due to their variable actions on adrenergic alpha (α) and beta (β) receptors, as well as vasopressin1 and vasopressin2 receptors located in these tissues.

Postpartum hemorrhage (PPH) remains a leading cause of maternal death and morbidity. Moreover, it also contributes to psychological trauma such as depression and post-traumatic stress disorder. The American College of Obstetrics and Gynecology (ACOG) and the Society for Maternal Fetal Medicine (SMFM) defines this morbidity as an unintended outcome in the birthing process that may have significant short-term and long-term consequences to an individual's health. A recent study in 2018 developed core outcomes set for PPH through Delphi consensus encompassing elements of prevention and management of PPH. Patient-reported outcomes, breastfeeding, and overall sense of wellbeing were not included in the final outcome set. Nevertheless, investigators felt strongly that they should be included, but further work was needed to assess the factors influencing the quality of recovery in the context of PPH. This is aligned with increasing recognition that patient experiences are important to improving the quality of care and quality of recovery after Cesarean delivery. The most effective, i.e. validated tool for assessing postpartum recovery is the Obstetric Quality of Recovery-10 (Obs-QoR-10). However its application in patients with PPH remains unexplored. It would appear logical that patient experiencing PPH experience a potentially more challenging recovery process which may include more surgical complications, depressive symptoms, sleep deprivation, physical exhaustion and stress due to unexpected and undesired delivery events. This study aims to compare Obs-QoR-10 scores in patients with and without PPH to evaluate the impact of severe postpartum bleeding on recovery outcomes using a matched case-control design. The investigators plan to determine the differences in Obs-QoR-10 scores between patients who experience PPH during childbirth and those deliver without PPH, and to evaluate the impact of PPH on specific recovery domains (physical comfort, emotional well-being, and functional recovery).

Postpartum hemorrhage (PPH) continues to be an increasing problem globally. Uterotonics play an essential role in the pharmacological management of uterine atony. Carbetocin, a long acting analog of oxytocin has been recommended as a first line uterotonic for PPH prophylaxis at cesarean delivery. Considering many woman have associated comorbidities and are at high risk of PPH, finding alternative pharmacological agents is essential. Calcium is a key factor for myometrial contractions and calcium blood levels can be low at the end of pregnancy. Both hypocalcemia and hypercalcemia could lead to a decrease in myometrial contractions. It is already been demonstrated that in both desensitized and naïve myometrium, normocalcemia provides a better uterine tone compared to hypo and hypercalcemia when oxytocin is given as the first uterotonic drug. Currently, the role of extracelullar calcium in carbetocin- induced contractility is unknown. This will be the first ex vivo study to test the effects of extracellular calcium on oxytocin pretreated and naive myometrium. The results of this study will provide evidence on the use of this safe drug in clinical practice, particularly in women with labour arrest, and provide alternative pharmacological strategies to both prevention and treatment of PPH, thus improving our clinical practice. The investigators hypothesize that extracellular normocalcemia would provide superior carbetocin-mediated contractility in both naive and oxytocin-pretreated myometrium compared with hypercalcemia and hypocalcemia.

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.

There is no widely used, statistically validated assessment for physical and mental health for the short- to medium-term in a postpartum population. PROMIS-29 has been validated for the assessment of these factors in a generic population, but has not been specifically evaluated for use with postpartum women. This study is a longitudinal, single center observational cohort study designed to evaluate the reliability of the Patient-Reported Outcomes Measurement Information System (PROMIS)-29 v2.1 survey in a postpartum population. PROMIS-29 is a survey designed to screen for pain, impairments in mood, physical function, and activities of daily living. While this survey has shown utility in other populations, it has yet to be assessed in an obstetric population. The investigators plan to recruit patients who are recently postpartum from vaginal or cesarean delivery to complete virtual surveys at defined time points (0, 2, 6, and 12 weeks after delivery). The investigators will subject survey data to statistical measures of validity and reliability comparing with contemporaneously collected surveys of established metrics for quality of life (WHOQoLBREF) and general (global) state of health (numerical rating score 1-100). The hypothesis is that the PROMIS-29 v2.1 questionnaire is a statistically valid and reliable means of assessing physical and mental health in a postpartum population.

The proposed study is to compare a modified DE technique, which is regularly used for low-risk patients by staff anesthesiologists at our institution, to a standard awake extubation. This modified deep extubation (mDE) occurs while the patient is still anaesthetized but at a lower dose of anaesthetic gas than previously described, and balanced with long acting opioids to attenuate the airway reaction. As previously stated, the literature shows that the risks of DE are equivalent to those of regular AE practice. Our hypothesis is that mDE will shorten the time from the end of the surgery (completion of last stitch) to the moment the patient is ready to leave the OR by at least 5 minutes when compared to standard AE practice.