Stability and compatibility of an intramuscular fetal anesthetic cocktail for fetal intervention.

INTRODUCTION: To evaluate chemical stability and physical compatibility when combining fentanyl, rocuronium, and atropine in a fixed ratio to support intramuscular drug delivery during fetal intervention and surgery. METHODS: A highly concentrated combination of fentanyl, rocuronium, and atropine was created based on common prescribing practices at a maternal fetal care center. Chemical stability testing was completed using liquid chromatograph mass spectrometry-mass spectrometry (LC/MS-MS) to detect and quantitate atropine, rocuronium, and fentanyl, with fentanyl-d5 being an internal standard at 6-, 12, 24-, and 36-hours following sample preparation. Physical compatibility testing was completed using United State Pharmacopeia (USP)<788> recommended analytical technique of light obscuration (LO) in addition to novel backgrounded membrane imaging (BMI) at 6- and 24-hours following sample preparation. Physical compatibility was determined using USP<788> particle count limits for both techniques. RESULTS: Based on LC/MS-MS results, the samples retained expected medication concentrations at all time points tested. For physical compatibility testing, the particle counts met criteria to be considered compatible per USP<788> large volume particle count thresholds at 6 hours by both methods but exceeded tolerable thresholds at 24 hours. DISCUSSION/CONCLUSION: The combination of rocuronium, fentanyl, and atropine for intramuscular fetal administration are physically compatible and chemically stable for 6 hours.

Detection of Postpartum Hemorrhage Using Compensatory Reserve Index in Patients Undergoing Cesarean Delivery.

BACKGROUND: Postpartum hemorrhage (PPH) is the leading cause of maternal death worldwide. Early recognition and management are imperative for improved outcomes. The compensatory reserve index (CRI) is a novel physiological parameter that trends changes in intravascular volume, by continuously comparing extracted photoplethysmogram waveforms to a reference model that was derived from a human model of acute blood loss. This study sought to determine whether the CRI pattern was differential between those who do and do not experience PPH during cesarean delivery and compare these results to the American Society of Anesthesiologists (ASA) standards for noninvasive monitoring. METHODS: Parturients undergoing cesarean delivery were enrolled between February 2020 and May 2021. A noninvasive CRI monitor was applied to collect continuous CRI values throughout the intraoperative and immediate postpartum periods. Patients were stratified based on blood loss into PPH versus non-PPH groups. PPH was defined as a quantitative blood loss >1000 mL. Function-on-scalar (FoS) regression was used to compare trends in CRI between groups (PPH versus non-PPH) during the 10 to 60-minute window after delivery. Two subanalyses excluding patients who received general anesthesia and preeclamptics were performed. RESULTS: Fifty-one patients were enrolled in the study. Thirteen (25.5%) patients experienced PPH. Pregnant patients who experienced PPH had, on average, lower postdelivery CRI values (-0.13; 95% CI, -0.13 to -0.12; P < .001) than those who did not experience PPH. This persisted even when adjusting for preeclampsia and administration of uterotonics. The average mean arterial pressure (MAP) measurements were not statistically significant (-1.67; 95% CI, -3.57 to 0.22; P = .09). Similar trends were seen when excluding patients who underwent general anesthesia. When excluding preeclamptics, CRI values remained lower in those who hemorrhaged (-0.18; 95% CI, -0.19 to -0.17; P < .001). CONCLUSIONS: CRI detects changes in central volume status not distinguished by MAP. It has the potential to serve as a continuous, informative metric, notifying providers of acute changes in central volume status due to PPH during cesarean delivery.

Evolution of postoperative care: marked reduction of opioid consumption when ERAC pathway added to wound soaker therapy for cesarean delivery.

OBJECTIVE: Achieving functional recovery after cesarean delivery is critical to a parturient's ability to care for herself and her newborn. Adequate pain control is vital, and without it, many other aspects of the recovery process may be delayed. Reducing opioid consumption without compromising analgesia is of paramount importance, and enhanced recovery pathways have generated considerable interest given their ability to facilitate this. Our group's process for reducing opioid consumption for cesarean delivery patients evolved over time. We first demonstrated that providing additional incisional pain control with continuous bupivacaine infusions through wound catheters, with the concurrent use of neuraxial morphine, reduced postoperative opioid use. Iterations of an enhanced recovery after cesarean (ERAC) delivery pathway were then implemented after the Society for Obstetric Anesthesia and Perinatology's consensus statement for ERAC was issued to eliminate variability in both hospital course and in the treatment of postoperative pain. In this retrospective cohort analysis, we sought to identify whether adding ERAC protocols to our existing combination of neuraxial morphine and wound soaker catheters further reduced opioid consumption after cesarean delivery. METHODS: A retrospective cohort analysis of cesarean deliveries from 2015 through 2020 was performed. Deliveries were divided by analgesic pathway into four time-periods - time-point 1 [January 2015-April 2016, previous standard of care (control, N = 61)]: neuraxial morphine in addition to as needed opioid and non-opioid analgesics; time-point 2 [May 2016-May 2019, introduction of wound soaker (wound-soaker, N = 40)]: continuous wound catheter infusions of local anesthetic, neuraxial morphine in addition to as needed opioid and non-opioid analgesics; time-point 3 [May 2019-December 2019, wound soaker + early ERAC pathway (early ERAC, N = 78)]: continuous wound catheter infusion of local anesthetic, neuraxial morphine, in addition to scheduled non-opioid analgesics (acetaminophen and ibuprofen) every 6 h, alternating in relation to one another so that one is given every 3 h; time-point 4 [January 2020-July 2020, wound soaker + late ERAC pathway (late ERAC, N = 57)]: continuous wound catheter infusion of local anesthetic, neuraxial morphine in addition to non-opioid analgesics scheduled together every 6 h (to facilitate periods of uninterrupted rest). Cumulative and average daily opioid use for postoperative days (POD) 1-4 were analyzed using ANOVA and a mixed effect model, respectively. RESULTS: Average daily opioid consumption and total cumulative opioid consumption POD 1-4 (morphine milligram equivalents) for both early and late ERAC groups (23.9 ± 31.1 and 29.4 ± 35.1) were significantly reduced compared to control and wound soaker groups (185.1 ± 93.7 and 134.8 ± 77.1) (p < .001). CONCLUSION: The addition of ERAC protocols to our standardized multimodal analgesic regimen (local anesthetic wound infusion catheters and neuraxial morphine) for cesarean delivery significantly reduced postoperative opioid consumption.

Avoiding the Use of Halogenated Anesthetic Agents for Uterine Relaxation in Open Mid-Gestation Fetal Surgery: A Case Report.

INTRODUCTION: Profound uterine relaxation is required for open fetal surgery. This is typically achieved by the administration of high-dose halogenated anesthetic agents. However, this anesthetic technique is associated with adverse cardiovascular effects in the fetus and may have long-term neurocognitive effects as well. CASE PRESENTATION: We pre-sent reports for 2 patients in whom uterine relaxation was maintained with nitroglycerin and magnesium infusions without any exposure to halogenated anesthetic agents. There were no adverse fetal or maternal effects from this technique. DISCUSSION/CONCLUSION: To the best of our knowledge, these are the first reports of open fetal surgery being performed without the use of halogenated anesthetic agents. This has potential short- and long-term benefits for the fetus, particularly as more complex and longer duration minimally invasive procedures are developed.

Anesthesia for Maternal-Fetal Interventions: A Survey of Fetal Therapy Centers in the North American Fetal Therapy Network.

INTRODUCTION: A wide range of fetal interventions are performed across fetal therapy centers (FTCs). We hypothesized that there is significant variability in anesthesia staffing and anesthetic techniques. METHODS: We conducted an online survey of anesthesiology directors at every FTC within the North American Fetal Therapy Network (NAFTNet). The survey included details of fetal interventions performed in 2018, anesthesia staffing models, anesthetic techniques, fetal monitoring, and postoperative management. RESULTS: There was a 92% response rate. Most FTCs are located within an adult hospital and employ a small team of anesthesiologists. There is heterogeneity when evaluating anesthesiology fellowship training and staffing, indicating there is a multidisciplinary specialty team-based approach even within anesthesiology. Minimally invasive fetal interventions were the most commonly performed. The majority of FTCs also performed ex utero intrapartum treatment (EXIT) and open mid-gestation procedures under general anesthesia (GA). Compared to FTCs only performing minimally invasive procedures, FTCs performing open fetal procedures were more likely to have a pediatric surgeon as director and performed more minimally invasive procedures. CONCLUSIONS: There is considerable variability in anesthesia staffing, caseload, and anesthetic techniques among FTCs in NAFTNet. Most FTCs used maternal sedation for minimally invasive procedures and GA for EXIT and open fetal surgeries.

Nitrous Oxide Use During Labor: Satisfaction, Adverse Effects, and Predictors of Conversion to Neuraxial Analgesia.

INTRODUCTION: Women desire safe and effective choices for pain management during labor. Currently, neuraxial and opioid analgesia are the most common methods used in the United States. The purpose of this study was to investigate demographic characteristics, safety, and satisfaction in a cohort of parturients who used inhaled nitrous oxide (N2 O) analgesia and to determine predictors of conversion from N2 O to neuraxial analgesia. METHODS: This was a prospective chart review study. Individuals aged at least 18 years who used inhaled N2 O during the first or second stage of labor between March 1, 2016, and July 23, 2017, on the labor and delivery unit of one academic medical center (N = 463) and their neonates were included. Data describing maternal and neonatal factors are reported. Logistic regression and chi-square tests were used to model the effects of oxytocin augmentation, labor induction, parity, prior cesarean birth, pre-N2 O cervical dilatation, and post-N2 O cervical dilatation on the odds of conversion from N2 O to neuraxial analgesia. RESULTS: In this cohort, 31% who chose N2 O for analgesia did not convert to any other analgesic method. Significant positive predictors for conversion from N2 O to neuraxial analgesia included labor induction (odds ratio [OR], 2.9; 95% CI, 1.7-5.0), oxytocin augmentation (OR, 3.1; 95% CI, 1.6-6.0), and labor after cesarean (OR, 6.4; 95% CI, 2.5-16.5). Multiparity (OR, 0.4; 95% CI, 0.2-0.6) and post-N2 O cervical dilatation (OR, 0.8; 95% CI, 0.7-0.9) were negative predictors. Adverse effects related to N2 O use during labor were rare (8%) and were not a significant reason for conversion to neuraxial analgesia. Parturients had moderately high satisfaction with N2 O for pain management (11-point scale, mean [SD], 7.4 [2.9]). Five-minute Apgar scores were 7 or greater in 97.8% of the newborns. DISCUSSION: Understanding predictors of conversion from inhaled N2 O to neuraxial analgesia may assist perinatal care providers in their discussions with women about analgesia options during labor. N2 O is a useful, safe option for labor analgesia in the United States.

Intraoperative ventilation: incidence and risk factors for receiving large tidal volumes during general anesthesia.

BACKGROUND: There is a growing concern of the potential injurious role of ventilatory over-distention in patients without lung injury. No formal guidelines exist for intraoperative ventilation settings, but the use of tidal volumes (VT) under 10 mL/kg predicted body weight (PBW) has been recommended in healthy patients. We explored the incidence and risk factors for receiving large tidal volumes (VT > 10 mL/kg PBW). METHODS: We performed a cross-sectional analysis of our prospectively collected perioperative electronic database for current intraoperative ventilation practices and risk factors for receiving large tidal volumes (VT > 10 mL/kg PBW). We included all adults undergoing prolonged (≥ 4 h) elective abdominal surgery and collected demographic, preoperative (comorbidities), intraoperative (i.e. ventilatory settings, fluid administration) and postoperative (outcomes) information. We compared patients receiving exhaled tidal volumes > 10 mL/kg PBW with those that received 8-10 or < 8 mL/kg PBW with univariate and logistic regression analyses. RESULTS: Ventilatory settings were non-uniform in the 429 adults included in the analysis. 17.5% of all patients received VT > 10 mL/kg PBW. 34.0% of all obese patients (body mass index, BMI, ≥ 30), 51% of all patients with a height < 165 cm, and 34.6% of all female patients received VT > 10 mL/kg PBW. CONCLUSIONS: Ventilation with VT > 10 mL/kg PBW is still common, although poor correlation with PBW suggests it may be unintentional. BMI ≥ 30, female gender and height < 165 cm may predispose to receive large tidal volumes during general anesthesia. Further awareness of patients' height and PBW is needed to improve intraoperative ventilation practices. The impact on clinical outcome needs confirmation.

Cystic appearance of low-grade endometrial stromal sarcoma in the right atrium: case report.

A 71-year-old woman presented with a right adnexal solid mass invading the right gonadal vein and inferior vena cava up to the hepatic veins revealed by CT and confirmed by MRI. A thin-walled cyst and a solid mass were unexpectedly found in the right atrium by transesophageal echocardiography (TEE) in the operating room. Using color Doppler and air bubbles as contrast material a circumscribed cyst was confirmed and localized close to the IVC. The cyst was connected to the mass in the inferior vena cava. The tumor, including the cyst, was removed without using cardiopulmonary bypass and described as a low-grade endometrial stromal sarcoma, a rare slowly growing tumor. This is the first TEE description of endometrial stromal sarcoma manifesting as a right atrial cyst.