The 90% effective dose of intrathecal hyperbaric bupivacaine for Cesarean delivery under combined spinal-epidural anesthesia in parturients with super obesity: an up-down sequential allocation study.

PURPOSE: To determine the 90% effective dose (ED90) of intrathecal hyperbaric bupivacaine for Cesarean delivery under combined spinal-epidural anesthesia (CSE) in parturients with super obesity (body mass index [BMI] ≥ 50 kg·m-2). METHODS: We enrolled parturients with BMI ≥ 50 kg·m-2 with term, singleton vertex pregnancies undergoing elective Cesarean delivery under CSE. An independent statistician generated the 0.75% hyperbaric bupivacaine dosing regimen in increments of 0.75 mg using a biased-coin up-down sequential allocation technique. This was combined with 15 µg fentanyl, 150 µg morphine, and normal saline to a volume of 2.05 mL. The initial and maximum doses were 9.75 mg and 12 mg, respectively. Participants, clinical team, and outcome assessors were blinded to the dose. The primary outcome was block success, defined as T6 block to pinprick within ten minutes and no intraoperative analgesic supplementation within 90 min of spinal injection. We determined the ED90 using logistic regression. RESULTS: We enrolled 45 parturients and included 42 in the analysis. All doses achieved a T6 level within ten minutes, and the primary outcome occurred in 0/1 (0%) of the 9.75-mg doses, 2/3 (67%) of the 10.5-mg doses, 21/27 (78%) of the 11.25-mg doses, and 11/11 (100%) of the 12-mg doses. The ED90 of hyperbaric bupivacaine was 11.56 mg (95% confidence interval, 11.16 to 11.99). Four parturients (9.5%) had sensory level higher than T2, but none was symptomatic or required general anesthesia. CONCLUSION: The estimated ED90 of hyperbaric bupivacaine with fentanyl and morphine in parturients with super obesity undergoing Cesarean delivery under CSE was approximately 11.5 mg. STUDY REGISTRATION: ClinicalTrials.gov (NCT03781388); first submitted 18 December 2018.

RéSUMé: OBJECTIF: Notre objectif était de déterminer la dose efficace à 90 % (DE90) de bupivacaïne hyperbare intrathécale pour l'accouchement par césarienne sous péri-rachianesthésie combinée (PRC) chez les personnes parturientes atteintes de super obésité (indice de masse corporelle [IMC] ≥ 50 kg·m−2). MéTHODE: Nous avons recruté des personnes parturientes ayant un IMC ≥ 50 kg·m−2 présentant des grossesses uniques à terme, en présentation céphalique et bénéficiant d'un accouchement par césarienne programmée sous PRC. Un·e statisticien·ne indépendant·e a généré le schéma posologique de bupivacaïne hyperbare à 0,75 % par incréments de 0,75 mg à l'aide d'une technique d'allocation séquentielle en escalier. La bupivacaïne a été combinée à 15 µg de fentanyl, 150 µg de morphine et à une solution physiologique salée jusqu'à un volume de 2,05 mL. Les doses initiale et maximale étaient respectivement de 9,75 mg et 12 mg. Les participant·es, l'équipe clinique et les personnes évaluant les résultats n'avaient pas connaissance de la dose. Le critère d'évaluation principal était la réussite du bloc, définie comme un bloc à T6 à la piqûre dans les dix minutes et aucune supplémentation analgésique peropératoire dans les 90 minutes suivant l'injection rachidienne. Nous avons déterminé la DE90 à l'aide d'une méthode de régression logistique. RéSULTATS: Nous avons recruté 45 personnes parturientes et en avons inclus 42 dans l'analyse. Toutes les doses ont atteint le niveau T6 en dix minutes, et le critère d'évaluation principal a été obtenu pour 0/1 (0 %) des doses de 9,75 mg, 2/3 (67 %) des doses de 10,5 mg, 21/27 (78 %) des doses de 11,25 mg et 11/11 (100 %) des doses de 12 mg. La DE90 de bupivacaïne hyperbare était de 11,56 mg (intervalle de confiance à 95 %, 11,16 à 11,99). Quatre personnes parturientes (9,5 %) ont affiché un niveau sensoriel supérieur à T2, mais aucune n'était symptomatique ni n'a nécessité d'anesthésie générale. CONCLUSION: La DE90 estimée de bupivacaïne hyperbare avec fentanyl et morphine chez les personnes parturientes hyperobèses bénéficiant d'une césarienne sous PRC était d'environ 11,5 mg. ENREGISTREMENT DE L'éTUDE: ClinicalTrials.gov (NCT03781388); soumis pour la première fois le 18 décembre 2018.

Automated mandatory bolus versus basal infusion for maintenance of epidural analgesia in labour.

BACKGROUND: Epidural analgesia is often used for pain relief during labour and childbirth, and involves administration of local anaesthetics (LA) into the epidural space resulting in sensory blockade of the abdomen, pelvis, and perineum. Epidural opioids are often co-administered to improve analgesia. Administration of epidural medications can be accomplished by basal infusion (BI) or automated mandatory bolus (AMB). With BI, medications are administered continuously, while AMB involves injecting medications at set time intervals. Patient-controlled epidural analgesia (PCEA) on top of AMB or BI enables patients to initiate additional boluses of epidural medications.  The superior method of delivering epidural medications would result in lower incidence of pain requiring anaesthesiologist intervention (breakthrough pain). Also, it should be associated with lower incidence of epidural-related adverse effects including caesarean delivery, instrumental delivery (use of forceps or vacuum devices), prolonged duration of labour analgesia, and LA consumption. However, clear evidence of the superiority of one technique over the other is lacking. Also, differences in the initiation of epidural analgesia such as combined spinal-epidural (CSE) (medications given into the intrathecal space in addition to the epidural space) compared to epidural only, and medications used (types and doses of LA or opioids) may not have been accounted for in previous reviews.  Our prior systematic review suggested that AMB reduces the incidence of breakthrough pain compared to BI with no significant difference in the incidence of caesarean delivery or instrumental delivery, duration of labour analgesia, and LA consumption. However, several studies comparing AMB and BI have been performed since then, and inclusion of their data may improve the precision of our effect estimates. OBJECTIVES: To assess the benefits and harms of AMB versus BI for maintaining labour epidural analgesia in women at term. SEARCH METHODS: We searched CENTRAL, Wiley Cochrane Library), MEDLINE, (National Library of Medicine), Embase(Elseiver), Web of Science (Clarivate), the WHO-ICTRP (World Health Organization) and ClinicalTrials.gov (National Library of Medicine) on 31 December 2022. Additionally, we screened the reference lists of relevant trials and reviews for eligible citations, and we contacted authors of included studies to identify unpublished research and ongoing trials. SELECTION CRITERIA: We included all randomised controlled studies that compared bolus dosing AMB with continuous BI during epidural analgesia. We excluded studies of women in preterm labour, with multiple pregnancies, with fetal malposition, intrathecal catheters, those that did not use automated delivery of medications, and those where AMB and BI were combined. DATA COLLECTION AND ANALYSIS: We used standard methodology for systematic review and meta-analysis described by Cochrane. Primary outcomes included: incidence of breakthrough pain requiring anaesthesiologist intervention; incidence of caesarean delivery; and incidence of instrumental delivery. Secondly, we assessed the duration of labour; hourly LA consumption in bupivacaine equivalents, maternal satisfaction after fetal delivery, and neonatal Apgar scores.  The following subgroup analyses were chosen a priori: epidural alone versus CSE technique; regimens that used PCEA versus those that did not; and nulliparous versus combination of nulli- and multi-parous women. We used the GRADE system to assess the certainty of evidence associated with our outcome measures. MAIN RESULTS: We included 18 studies of 4590 women, of which 13 enrolled healthy nulliparous women and five included healthy nulli- and multiparous women. All studies excluded women with preterm or complicated pregnancies. Techniques used to initiate epidural analgesia differed between the studies: seven used combined spinal epidural, 10 used epidural, and one used dural puncture epidural (DPE). There was also variation in analgesics used. Eight studies utilised ropivacaine with fentanyl, three used ropivacaine with sufentanil, two utilised levobupivacaine with sufentanil, one used levobupivacaine with fentanyl, and four utilised bupivacaine with fentanyl. Most of the studies were assessed to have low risk of randomisation, blinding, attrition, and reporting biases, except for allocation concealment where eight studies were assessed to have uncertain risk and three with high risk. Our results showed that AMB was associated with lower incidence of breakthrough pain compared to BI (risk ratio (RR) 0.71; 95% confidence interval (CI) 0.55 to 0.91; I2 = 57%) (16 studies, 1528 participants), and lower hourly LA consumption in bupivacaine equivalents (mean difference (MD) -0.84 mg/h; 95% CI -1.29 to -0.38, I2 = 87%) (16 studies, 1642 participants), both with moderate certainty. AMB was associated with an estimated reduction in breakthrough pain incidence of 29.1% (incidence 202 per 1000, 95% CI 157 to 259), and was therefore considered clinically significant. The incidence of caesarean delivery (RR 0.85; 95% CI 0.69 to 1.06; I2 = 0%) (16 studies, 1735 participants) and instrumental delivery (RR 0.85; 95% CI 0.71 to 1.01; I2 = 0%) (17 studies, 4550 participants) were not significantly, both with moderate certainty. There was no significant difference in duration of labour analgesia (MD -8.81 min; 95% CI -19.38 to 1.77; I2 = 50%) (17 studies, 4544 participants) with moderate certainty. Due to differences in the methods and timing of outcome measurements, we did not pool data for maternal satisfaction and Apgar scores. Results reported narratively suggest AMB may be associated with increased maternal satisfaction (eight studies reported increased satisfaction and six reported no difference), and all studies showed no difference in Apgar scores. WIth the exception of epidural alone versus CSE which found significant subgroup differences in LA consumption between AMB and BI, no significant differences were detected in the remaining subgroup analyses. AUTHORS' CONCLUSIONS: Overall, AMB is associated with lower incidence of breakthrough pain, reduced LA consumption, and may improve maternal satisfaction. There were no significant differences between AMB and BI in the incidence of caesarean delivery, instrumental delivery, duration of labour analgesia, and Apgar scores. Larger studies assessing the incidence of caesarean and instrumental delivery are required.

Investigating the association factors of acute postpartum pain: a cohort study.

BACKGROUND: Labor pain intensity is known to predict persistent postpartum pain, whereas acute postpartum pain may interfere with maternal postpartum physical, mental, and emotional well-being. Nevertheless, there is little research studying the association between labor pain intensity and acute postpartum pain. This study investigated the associations between labor pain intensity and psychological factors with acute postpartum pain. METHODS: We included women with American Society of Anesthesiologists (ASA) physical status II, having ≥ 36 gestational weeks and a singleton pregnancy. We investigated the association between labor pain intensity (primary exposure) and high acute postpartum pain at 0 to 24 h after delivery (Numeric Rating Scale (NRS) ≥ 3 of 10; primary outcome). Pre-delivery questionnaires including Angle Labor Pain Questionnaire (A-LPQ), Pain Catastrophizing Scale (PCS), Fear Avoidance Components Scale (FACS) and State Trait Anxiety Inventory (STAI) were administered. Demographic, pain, obstetric and neonatal characteristics were also collected accordingly. RESULTS: Of the 880 women studied, 121 (13.8%) had high acute postpartum pain at 0 to 24 h after delivery. A-LPQ total, PCS, FACS and STAI scores were not significantly associated with acute postpartum pain. Greater A-LPQ subscale on birthing pain (adjusted odds ratio (aOR) 1.03, 95% CI 1.01-1.05, p = 0.0008), increased blood loss during delivery (for every 10ml change; aOR 1.01, 95% CI 1.00-1.03, p = 0.0148), presence of shoulder dystocia (aOR 10.06, 95% CI 2.28-44.36, p = 0.0023), and use of pethidine for labor analgesia (aOR 1.74, 95% CI 1.07-2.84, p = 0.0271) were independently associated with high acute postpartum pain. "Sometimes" having nausea during menstruation before current pregnancy (aOR 0.34, 95% CI 0.16-0.72, p = 0.0045) was found to be independently associated with reduced risk of high acute postpartum pain. CONCLUSIONS: Pre-delivery pain factor together with obstetric complications (shoulder dystocia, blood loss during delivery) were independently associated with high acute postpartum pain. TRIAL REGISTRATION: This study was registered on clinicaltrials.gov registry (NCT03167905) on 30/05/2017.

Effect of music listening on perioperative anxiety, acute pain and pain catastrophizing in women undergoing elective cesarean delivery: a randomized controlled trial.

BACKGROUND: Anxiety may adversely impact mother and her newborn. Music listening is a safe and efficacious treatment that may to reduce perioperative anxiety. The effect on acute pain and pain catastrophizing scores remains unclear. We aimed to determine whether perioperative music listening reduces anxiety, acute pain, and pain catastrophizing scale (PCS) scores following elective cesarean delivery under spinal anesthesia. METHODS: After randomization into music listening and control groups, baseline patient characteristics, visual analog scale-anxiety (VAS-A) scores, pain scores, PCS total and sub-scores, and music preferences were collected preoperatively. Before surgery, parturients in the experimental group listened to music of their own choice for 30 min. Music listening was continued during administration of spinal anesthesia and cesarean delivery, and for 30 min following surgery. Postoperative VAS-A score, acute pain score, PCS scores, music preferences, satisfaction score, and feedback were recorded. RESULTS: We analyzed 108 parturients (music: n = 53; control: n = 55). Music listening was associated with reduced postoperative VAS-A (mean difference (MD) -1.43, 95%CI -0.63 to -2.22), PCS total score (MD -6.39, 95%CI -2.11 to -10.66), PCS sub-scores on rumination (MD -1.68, 95%CI -0.12 to -3.25), magnification (MD -1.53, 95%CI -0.45 to -2.62), and helplessness (MD -3.17, 95%CI -1.29 to -5.06) sub-scores. There was no significant difference in postoperative acute pain scores. The majority (> 95%) of parturients reported "excellent" and "good" satisfaction with music listening, and most provided positive feedback. CONCLUSION: Perioperative music listening was associated with reduced postoperative anxiety and lower pain catastrophizing. Based on the good patient satisfaction and positive feedback received, the use of music listening in the obstetric setting is recommended. TRIAL REGISTRATION: This study was registered on Clinicaltrials.gov NCT03415620 on 30/01/2018.

Evaluating an advanced double intravenous vasopressor automated system to treat hypotension during spinal anesthesia for cesarean delivery: a randomized controlled trial.

BACKGROUND: The optimal treatment of hypotension during spinal anaesthesia is uncertain. A novel double intravenous vasopressor automated (DIVA) system reduces hypotension compared to standard care, and was subsequently modified to an advanced-DIVA (ADIVA) system. The primary objective was to compare ADIVA versus DIVA on incidence of hypotension (systolic BP (SBP) < 80% baseline). METHODS: We conducted a randomized-controlled trial in women undergoing elective cesarean delivery under spinal anesthesia. SBP and heart rate were measured continuously using a Nexfin monitor. ADIVA delivered 25 µg phenylephrine (heart rate > 60 beats.min-1) or 2 mg ephedrine (heart rate < 60 beats.min-1) at SBP 90 to 110% of baseline, 50 µg phenylephrine or 4 mg ephedrine at SBP 80 to 90%, and 75 µg phenylephrine or 6 mg ephedrine at SBP < 80%. ADIVA calculated the trend of SBP; vasopressors were administered rapidly if SBP trended downward, or 30 s if SBP trended upward. In contrast, DIVA delivered 25 µg phenylephrine or 2 mg ephedrine at SBP 90 to 100% of baseline, and 50 µg phenylephrine or 4 mg ephedrine at SBP < 90%. Boluses were followed by a 10-s lockout. Other outcomes included hypertension (SBP > 120% baseline), vasopressor consumption, clinical outcomes, and performance measures from spinal anesthesia to fetal delivery. RESULTS: We analyzed 94 parturients (ADIVA: n = 46, DIVA: n = 48), with no difference in the incidence of hypotension between ADIVA (78.3%) and DIVA (83.3%, p = 0.677). ADIVA had significantly higher proportion of hypotensive SBP readings, lower phenylephrine consumption and higher umbilical arterial pH. There was no difference in hypertension, bradycardia, ephedrine consumption, intravenous fluid volume, nausea/vomiting, Apgar scores, and umbilical venous pH or lactate. ADIVA maintained SBP higher above baseline with greater fluctuation than DIVA. CONCLUSION: ADIVA was associated with a greater proportion of hypotensive SBP readings, reduced phenylephrine consumption, and increased umbilical arterial pH than DIVA. Further research is needed to determine the optimal method of vasopressor delivery in parturients undergoing cesarean delivery. TRIAL REGISTRATION: This study was registered on Clinicaltrials.gov registry (NCT03620942) on 08/08/2018.

Inflammatory changes in the plasma and cerebrospinal fluid of patients with persistent pain and postpartum depression after elective Cesarean delivery: an exploratory prospective cohort study.

PURPOSE: Severe acute pain after Cesarean delivery increases the risk of developing persistent pain (~20% incidence) and postpartum depression (PPD) (~15% incidence). Both conditions contribute to maternal morbidity and mortality, yet early risk stratification remains challenging. Neuroinflammation has emerged as a key mechanism of persistent pain and depression in nonobstetric populations. Nevertheless, most studies focus on plasma cytokines, and the relationship between plasma and cerebrospinal fluid (CSF) cytokine levels is unclear. Our primary aim was to compare inflammatory marker levels between patients who developed the composite outcome of persistent pain and/or PPD vs those who did not. METHODS: We recruited term patients with singleton pregnancies undergoing elective Cesarean delivery under neuraxial anesthesia into an exploratory prospective cohort study. We collected baseline demographic, obstetric, and Edinburgh Postnatal Depression Scale information, and performed quantitative sensory tests. Plasma was collected preoperatively and 48 hr postoperatively. In the operating room, 10 mL of CSF was collected, followed by a standardized anesthetic. Intra- and postoperative management were according to standard practice. We obtained Edinburgh Postnatal Depression Scale and pain scores at six weeks and three months after delivery. The primary outcome was persistent pain and/or PPD at three months. We analyzed the difference in inflammatory marker levels between the groups (primary aim) using two-sided Mann-Whitney tests. RESULTS: Eighty participants were enrolled, and 63 patients completed the study; 23 (37%) experienced the primary outcome at three months. Preoperative plasma transforming growth factor beta 1 (TGF-ß1) concentration was higher in patients who developed the primary outcome compared with those who did not (median [interquartile range (IQR)], 2,879 [2,241-5,494] vs 2,292 [1,676-2,960] pg·mL-1; P = 0.04), while CSF IL-1ß concentration was higher in patients who developed the primary outcome than in those who did not (median [IQR], 0.36 [0.29-0.39] vs 0.30 [0.25-0.35] pg·mL-1; P = 0.03). CONCLUSIONS: We observed differential levels of plasma and CSF inflammatory biomarkers in patients who developed persistent pain and PPD compared with those who did not. We showed the feasibility of collecting plasma and CSF samples at Cesarean delivery, which may prove useful for future risk-stratification. STUDY REGISTRATION: ClinicalTrials.gov (NCT04271072); registered 17 February 2020.

RéSUMé: OBJECTIF: La douleur aiguë sévère après un accouchement par césarienne augmente le risque de douleur persistante (~20 % d'incidence) et de dépression post-partum (DPP) (~15 % d'incidence). Ces deux conditions contribuent à la morbidité et à la mortalité maternelles, mais la stratification précoce des risques demeure difficile. La neuroinflammation est apparue comme un mécanisme clé de la douleur persistante et de la dépression dans les populations non obstétricales. Néanmoins, la plupart des études se concentrent sur les cytokines plasmatiques, et la relation entre les taux de cytokines plasmatiques et de liquide céphalorachidien (LCR) n'est pas claire. Notre objectif principal était de comparer les taux de marqueurs inflammatoires entre les patient·es qui ont eu un résultat composite de douleur persistante et/ou de DPP vs les personnes qui n'en ont pas eu. MéTHODE: Nous avons recruté des patient·es à terme avec des grossesses uniques bénéficiant d'une césarienne programmée sous anesthésie neuraxiale dans une étude de cohorte prospective exploratoire. Nous avons recueilli des informations démographiques de base, obstétricales et tirées de l'Échelle de dépression postnatale d'Édimbourg, et effectué des tests sensoriels quantitatifs. Le plasma a été prélevé avant l'opération et 48 heures après l'opération. En salle d'opération, 10 mL de LCR ont été recueillis, suivis d'un anesthésie standardisée. La prise en charge per- et postopératoire était conforme à la pratique courante. Nous avons obtenu les scores sur l'Échelle de dépression postnatale d'Édimbourg et les scores de douleur six semaines et trois mois après l'accouchement. Le critère d'évaluation principal était la douleur persistante et/ou la DPP à trois mois. Nous avons analysé la différence dans les niveaux de marqueurs inflammatoires entre les groupes (objectif principal) en utilisant des tests bilatéraux de Mann-Whitney. RéSULTATS: Quatre-vingts personnes ont été recrutées et 63 patient·es ont terminé l'étude; 23 (37 %) ont rapporté le critère d'évaluation principal à trois mois. Le facteur TGF-ß1 (transforming growth factor beta 1) plasmatique préopératoire était plus élevé chez les patient·es qui ont manifesté le critère d'évaluation principal par rapport aux personnes qui ne l'ont pas manifesté (médiane [écart interquartile (ÉIQ)], 2879 [2241-5494] vs 2292 [1676­2960] pg·mL−1; P = 0,04), tandis que le IL-1ß dans le LCR était plus élevé chez les patient·es qui ont manifesté le critère d'évaluation principal que chez les personnes qui ne l'ont pas manifesté (médiane [ÉIQ], 0,36 [0,29-0,39] vs 0,30 [0,25­0,35] pg·mL−1; P = 0,03). CONCLUSION: Nous avons observé des taux différentiels de biomarqueurs inflammatoires plasmatiques et de LCR chez les patient·es qui ont manifesté une douleur persistante et une DPP par rapport aux personnes qui n'en ont pas manifesté. Nous avons montré la faisabilité de la collecte d'échantillons de plasma et de LCR lors de l'accouchement par césarienne, ce qui pourrait s'avérer utile pour la stratification future des risques. ENREGISTREMENT DE L'éTUDE: clinicaltrials.gov (NCT04271072); enregistrée le 17 février 2020.

Quality of Labor Analgesia with Dural Puncture Epidural versus Standard Epidural Technique in Obese Parturients: A Double-blind Randomized Controlled Study.

BACKGROUND: The dural puncture epidural technique may improve analgesia quality by confirming midline placement and increasing intrathecal translocation of epidural medications. This would be advantageous in obese parturients with increased risk of block failure. This study hypothesizes that quality of labor analgesia will be improved with dural puncture epidural compared to standard epidural technique in obese parturients. METHODS: Term parturients with body mass index greater than or equal to 35 kg · m-2, cervical dilation of 2 to 7 cm, and pain score of greater than 4 (where 0 indicates no pain and 10 indicates the worst pain imaginable) were randomized to dural puncture epidural (using 25-gauge Whitacre needle) or standard epidural techniques. Analgesia was initiated with 15 ml of 0.1% ropivacaine with 2 µg · ml-1 fentanyl, followed by programed intermittent boluses (6 ml every 45 min), with patient-controlled epidural analgesia. Parturients were blinded to group allocation. The data were collected by blinded investigators every 3 min for 30 min and then every 2 h until delivery. The primary outcome was a composite of (1) asymmetrical block, (2) epidural top-ups, (3) catheter adjustments, (4) catheter replacement, and (5) failed conversion to regional anesthesia for cesarean delivery. Secondary outcomes included time to a pain score of 1 or less, sensory levels at 30 min, motor block, maximum pain score, patient-controlled epidural analgesia use, epidural medication consumption, duration of second stage of labor, delivery mode, fetal heart tones changes, Apgar scores, maternal adverse events, and satisfaction with analgesia. RESULTS: Of 141 parturients randomized, 66 per group were included in the analysis. There were no statistically or clinically significant differences between the dural puncture epidural and standard epidural groups in the primary composite outcome (34 of 66, 52% vs. 32 of 66, 49%; odds ratio, 1.1 [0.5 to 2.4]; P = 0.766), its individual components, or any of the secondary outcomes. CONCLUSIONS: A lack of differences in quality of labor analgesia between the two techniques in this study does not support routine use of the dural puncture epidural technique in obese parturients.

ED 90 of Intrathecal Chloroprocaine With Fentanyl for Prophylactic Cervical Cerclage: A Sequential Allocation Biased-Coin Design.

BACKGROUND: Chloroprocaine is a short-acting local anesthetic that has been used for spinal anesthesia in outpatient surgery. There is limited experience with spinal chloroprocaine for prophylactic cervical cerclage placement. We sought to determine the effective dose of intrathecal chloroprocaine for 90% of patients (ED90) undergoing prophylactic cervical cerclage placement. We hypothesized that the ED90 of intrathecal chloroprocaine when combined with 10-ug fentanyl would be between 33 and 54 mg. METHODS: In this prospective 2-center double-blinded study, we enrolled women undergoing prophylactic cervical cerclage placement under combined spinal-epidural anesthesia. A predetermined dose of intrathecal 3% chloroprocaine with fentanyl 10 ug was administered. The initial dose was 45-mg intrathecal chloroprocaine. Subsequent dose adjustments were determined based on the response of the previous subject using an up-down sequential allocation with a biased-coin design. A dose was considered effective if at least a T12 block was achieved, and there was no requirement for epidural activation or intraoperative analgesic supplementation during the procedure. The primary outcome was the ED90 of intrathecal chloroprocaine with fentanyl 10 ug. Secondary outcomes included duration of surgery, anesthetic side effects, time to resolution of motor and sensory block, time to achieve recovery room discharge criteria, and patient satisfaction with anesthetic care. Isotonic regression was used to estimate the ED90. RESULTS: Forty-seven patients were enrolled into the study. Two patients were excluded (1 protocol violation and 1 failed block). In total, 45 patients completed the study. The estimated ED90 (95% confidence interval) for intrathecal chloroprocaine combined with fentanyl 10 ug was 49.5 mg (45.0-50.1 mg). The median (interquartile range [IQR]) duration of surgery was 15 (10-24) minutes. Resolution of the motor (Bromage 0) and sensory block took a median time of 60 (45-90) minutes and 90 (75-105) minutes, respectively. The median time to achieve recovery room discharge criteria was 150 (139-186) minutes. Satisfaction with anesthetic management was high in all patients. There were no reports of postdural puncture headache or transient neurological symptoms postoperatively. CONCLUSIONS: The ED90 of intrathecal chloroprocaine combined with fentanyl 10 ug was 49.5 mg. Intrathecal chloroprocaine was associated with rapid block recovery and high patient satisfaction, which makes it well suited for outpatient obstetric procedures.

Uterine exteriorization versus in situ repair in Cesarean delivery: a systematic review and meta-analysis.

PURPOSE: We conducted an updated systematic review and meta-analysis on maternal outcomes associated with uterine exteriorization compared with in situ repair in women undergoing Cesarean delivery. METHODS: We searched for randomized controlled trials comparing uterine exteriorization with in situ repair during Cesarean delivery. Primary outcomes were intraoperative nausea and vomiting (IONV) and perioperative decrease in hemoglobin concentration. Secondary outcomes were postoperative nausea and vomiting (PONV), estimated blood loss, fever, endometritis, wound infection, intraoperative and postoperative pain, postoperative analgesic use, duration of surgery and hospital stay, and time to return of bowel function. RESULTS: Twenty studies with 20,909 parturients were included. Exteriorization was associated with higher risk of IONV (odds ratio [OR], 2.09; 95% confidence interval [CI], 1.66 to 2.63; I2 = 0%), with no difference in perioperative hemoglobin concentration decrease (mean difference, - 0.06 g·dL-1; 95% CI, - 0.20 to 0.08; I2 = 97%) compared with in situ repair. There were no significant differences in estimated blood loss, transfusion requirement, PONV, duration of surgery, duration of hospital stay, time to return of bowel function, fever, endometritis, or wound infection. Postoperative pain (incidence of pain graded > 5/10) at six hours (OR, 1.64; 95% CI, 1.31 to 2.03; I2 = 0%) was higher with exteriorization, but there was no difference in need for rescue analgesia (OR, 2.48; 95% CI, 0.89 to 6.90; I2 = 94%) or pain scores at 24 hr compared with in situ repair. CONCLUSIONS: In this updated systematic review and meta-analysis, uterine exteriorization was associated with an increased risk of IONV but no significant change in perioperative hemoglobin decrease compared with in situ repair. STUDY REGISTRATION: PROSPERO (CRD42020190074); registered 5 July 2020.

RéSUMé: OBJECTIF: Nous avons réalisé une mise à jour d'une revue systématique et une méta-analyse portant sur les issues maternelles associées à l'extériorisation de l'utérus par rapport à une réparation in situ chez les femmes accouchant par césarienne. MéTHODE: Nous avons recherché des études randomisées contrôlées comparant l'extériorisation de l'utérus à la réparation in situ pendant un accouchement par césarienne. Les critères d'évaluation principaux étaient les nausées et vomissements peropératoires (NVPerO) et la réduction périopératoire de l'hémoglobine. Les critères d'évaluation secondaires étaient les nausées et vomissements postopératoires (NVPO), la perte de sang estimée, la fièvre, l'endométrite, l'infection de la plaie, la douleur per- et postopératoire, l'utilisation d'analgésiques postopératoires, la durée de la chirurgie et du séjour à l'hôpital, et le délai jusqu'au retour du transit. RéSULTATS: Vingt études portant sur 20 909 parturientes ont été incluses. L'extériorisation était associée à un risque plus élevé de NVPerO (rapport de cotes [RC], 2,09; intervalle de confiance à 95 % [IC], 1,66 à 2,63; I2 = 0 %), sans différence dans la réduction de l'hémoglobine périopératoire (différence moyenne, − 0,06 g·dL-1; IC 95 %, − 0,20 à 0,08; I2 = 97 %) par rapport à une réparation in situ. Il n'y avait pas de différences significatives dans la perte de sang estimée, les besoins transfusionnels, les NVPO, la durée de la chirurgie, la durée du séjour à l'hôpital, le délai jusqu'au retour du transit, la fièvre, l'endométrite ou l'infection de la plaie. La douleur postopératoire (incidence de la douleur graduée > 5/10) à six heures (RC, 1,64; IC 95 %, 1,31 à 2,03; I2 = 0 %) était plus élevée avec une extériorisation, mais il n'y avait aucune différence dans les besoins d'analgésie de secours (RC, 2,48; IC 95 %, 0,89 à 6,90; I2 = 94 %) ou les scores de douleur à 24 heures par rapport à une réparation in situ. CONCLUSION: Dans cette revue systématique et méta-analyse mises à jour, l'extériorisation utérine était associée à un risque accru de NVPerO, mais à aucun changement significatif dans la réduction de l'hémoglobine périopératoire par rapport à la réparation in situ. ENREGISTREMENT DE L'éTUDE: PROSPERO (CRD42020190074); enregistrée le 5 juillet 2020.

The association between intravenous iron for antenatal anemia and postnatal depression: a retrospective cohort study.

PURPOSE: Determine if intravenous iron for antenatal anemia is associated with reduced incidence of postnatal depression (PND) within 12 months. METHODS: This retrospective cohort study included adult women with antenatal anemia (hemoglobin value of < 11.0 g/dL within 3 months before delivery). PND was defined as Edinburgh Postnatal Depression Scale (EPDS) or Patient Health Questionnaire-9 (PHQ-9) ≥ 10. Data on intravenous iron, lowest hemoglobin concentration, EPDS and PHQ-9 scores, insurance status, history of anxiety, depression, chronic pain, and substance use, obstetric complications, labor analgesia, and mode of delivery were obtained. Standardized mean difference (SMD) was estimated and multivariable logistic regression models were constructed with adjustment for potential confounders with absolute SMD of ≥ 0.1. RESULTS: Data from 3988 women were analyzed. The 368 (9.2%) women who received intravenous iron therapy had lower antenatal hemoglobin levels, were more likely to be African American or single/widowed women, and more commonly had  Medicaid coverage, repeat cesarean delivery, and history of depression compared to those who did not receive intravenous iron therapy. Unadjusted analysis showed women who received intravenous iron had higher incidence of PND (18.5%) than those who did not (13.4%) (p = 0.008). Multivariable analysis showed no significant association between intravenous iron and PND incidence (aOR 1.21, 95%CI 0.89-1.63, p = 0.232), although history of depression (aOR 2.42, 95%CI 1.91-3.08, p < 0.001), higher gravidity (aOR 1.09, 95%CI 1.02-1.17, p = 0.016), and Medicaid insurance (aOR 1.44, 95%CI 1.16-1.80, p = 0.001) were independently associated with PND. CONCLUSION: Intravenous iron for antenatal anemia was not associated with significant change in the incidence of PND.

Heart rate variability and haemodynamic factors associated with hypotension during spinal anaesthesia for caesarean delivery: A case-control study.

BACKGROUND: Hypotension frequently occurs during spinal anaesthesia for caesarean delivery, with potential adverse effects. OBJECTIVE: To investigate heart rate variability and haemodynamic factors associated with spinal anaesthesia-induced hypotension. DESIGN: Secondary case-control analysis of a randomised study. SETTING: Single obstetric centre. PATIENTS: Data were obtained from 230 healthy term singleton parturients who underwent elective caesarean delivery under spinal anaesthesia. INTERVENTION: With parturients at rest, continuous haemodynamic measurements were recorded using a Nexfin cardiac monitor. Baseline pre-operative values were defined as the average of five minutes of continuous measurements. After initiation of standardised spinal anaesthesia, vasopressors were administered to maintain SBP within 10% of pre-operative values. Hypotension was defined as any 10 seconds average SBP less than 80% of pre-operative values from initiation of spinal anaesthesia to foetal delivery. Parturients were classified into cases (hypotensive) or controls (normotensive), and both univariate and multivariable logistic regression models were used to identify independent factors associated with hypotension. MAIN OUTCOME MEASURES: Pre-operative standard deviation of the interbeat interval (SDNN), root mean square of successive interbeat difference, low-frequency to high-frequency ratio, SD1, SD2, approximate entropy, sample entropy, mean arterial pressure, SBP, stroke volume variation and systemic vascular resistance index were recorded, as were sensory block height, intravenous fluid volume and vasopressor use between spinal anaesthesia and foetal delivery. RESULTS: Of 230 parturients, 113 (49.1%) experienced hypotension. Pre-operative lower SDNN [odds ratio (OR) 0.87, 95% confidence interval (CI) 0.78 to 0.97], higher SD2 (OR 25.06, 95% CI 2.41 to 261.06), and lower SBP (OR 0.98, 95% CI 0.97 to 1.00) were independently associated with hypotension. Between spinal anaesthesia to foetal delivery, lower sensory block height (OR 0.76, 95% CI 0.65 to 0.90) and higher intravenous fluid volume (OR 0.98, 95% CI 0.96 to 0.99 per 15 ml change) were associated with a lower incidence of hypotension. Area under the receiver operating characteristic curve was 0.701. CONCLUSION: Pre-operative higher SD2, lower SDNN and lower SBP were associated with hypotension during spinal anaesthesia for caesarean delivery. TRIAL REGISTRATION: NCT02277730.

Analgesia After Cesarean Delivery in the United States 2008-2018: A Retrospective Cohort Study.

BACKGROUND: Optimizing analgesia after cesarean delivery is a priority and requires balancing adequate pain relief with the risk of analgesics-associated adverse effects. Current recommendations are for use of a multimodal, opioid-sparing analgesic regimen that includes neuraxial morphine combined with scheduled nonsteroidal anti-inflammatory drugs (NSAIDs) and scheduled acetaminophen. Furthermore, recent studies recommend scheduled acetaminophen with as-needed opioids in lieu of acetaminophen-opioid combination drugs to reduce opioid consumption and optimize analgesia. However, the extent of utilization of this recommended regimen in the United States is unclear. We therefore performed this retrospective study to evaluate postoperative analgesic regimens utilized after cesarean delivery under neuraxial anesthesia, examine variability across institutions, evaluate changes over time in postoperative analgesic practice, and examine factors associated with the use of neuraxial morphine and of multimodal analgesia. METHODS: This retrospective cohort study was approved by the Duke University Institutional Review Board. Parturients who underwent cesarean delivery under neuraxial anesthesia from 2008 to 2018 were included. Data were extracted from a nationwide inpatient administrative-financial database (Premier Inc, Charlotte, NC) and included parturient characteristics, comorbidities, hospital characteristics, and charges for administered medications. The primary outcome was the postoperative analgesic regimen utilized during hospitalization, including utilization of neuraxial morphine and of multimodal analgesia for postoperative pain control. We also examined the factors associated with the use of neuraxial morphine and of the multimodal regimen incorporating neuraxial morphine, NSAIDs, and acetaminophen. RESULTS: Data from 804,752 parturients were analyzed. Of this cohort, 75.8% received neuraxial morphine, 93.2% received NSAIDs, 28.4% received acetaminophen, and 81.3% received acetaminophen-opioid combination drugs. Only 6.1% received the currently recommended regimen of neuraxial morphine with NSAIDs and acetaminophen, with this percentage increasing from 1.3% in 2008 to 15.0% in 2018. On the other hand, 58.9% received neuraxial morphine, NSAIDs, and an acetaminophen-opioid combination drug, with this regimen being utilized in 57.0% of cases in 2008 and 58.1% in 2018. The hospital in which the patient was treated accounted for 54.7% of the variation in receipt of neuraxial morphine and 41.2% in the variation in receipt of multimodal analgesia with neuraxial morphine, NSAIDs, and acetaminophen, with this variability in receipt of neuraxial morphine and of multimodal analgesia being largely independent of patient characteristics. CONCLUSIONS: Relatively few parturients received the currently recommended multimodal analgesic regimen of neuraxial morphine with NSAIDs and acetaminophen after cesarean delivery. Additionally, the majority received acetaminophen-opioid combination drugs rather than plain acetaminophen. Further studies should investigate the implications for patient outcomes.

Correlation of patient characteristics with arm and finger measurements in Asian parturients: a preliminary study.

BACKGROUND: Accurate blood pressure (BP) measurement depends on appropriate cuff size and shape in relation to the arm. Arm dimensions outside the recommended range of cuff sizes or trunco-conical arms may result in inaccurate BP measurements. Measuring BP using finger cuffs is a potential solution. Arm cuff size is based on mid-arm circumference (MAC), and trunco-conicity is quantified by conicity index. We aimed to determine the correlation of MAC, body mass index (BMI), and weight with conicity index. METHODS: A prospective cohort study was conducted in the KK Women's and Children's Hospital where third trimester parturients scheduled for cesarean delivery were recruited after obtaining informed consent. Parturients were asked to rate their experience with time taken to obtain BP readings, cuff popping off during measurement, need to move the cuff from the upper arm to lower arm or leg, and need to change to a different cuff. Our primary outcome was the correlation between MAC and conicity index, calculated using Pearson's correlation. The correlation between BMI and weight with conicity index was also determined. RESULTS: We enrolled 300 parturients. Moderate correlation was found between left MAC and left conicity index (r = 0.41, 95% CI 0.32 to 0.51), and right MAC and right conicity index (r = 0.39, 95% CI 0.29 to 0.48). Weight (r = 0.35 to 0.39) and BMI (r = 0.41 to 0.43) correlated with conicity index in this study. MAC of 1 parturient fell outside the recommended range for arm cuffs, but all parturients fit into available finger cuffs. Obese parturients had increased problems with arm cuffs popping off and needing a change of cuff. CONCLUSIONS: BMI better correlated with conicity index compared to MAC or weight. Standard finger cuffs were suitable for all parturients studied and may be a suitable alternative. TRIAL REGISTRATION: Clinicaltrials.gov NCT04012151 . Registered 9 Jul 2019.

The effects of labor on airway outcomes with Supreme™ laryngeal mask in women undergoing cesarean delivery under general anesthesia: a cohort study.

BACKGROUND: Pregnancy is associated with higher incidence of failed endotracheal intubation and is exacerbated by labor. However, the influence of labor on airway outcomes with laryngeal mask airway (LMA) for cesarean delivery is unknown. METHODS: This is a secondary analysis of a prospective cohort study on LMA use during cesarean delivery. Healthy parturients who fasted > 4 h undergoing Category 2 or 3 cesarean delivery with Supreme™ LMA (sLMA) under general anesthesia were included. We excluded parturients with BMI > 35 kg/m2, gastroesophageal reflux disease, or potentially difficult airway (Mallampati score of 4, upper respiratory tract or neck pathology). Anesthesia and airway management reflected clinical standard at the study center. After rapid sequence induction and cricoid pressure, sLMA was inserted as per manufacturer's recommendations. Our primary outcome was time to effective ventilation (time from when sLMA was picked up until appearance of end-tidal carbon dioxide capnography), and secondary outcomes include first-attempt insertion failure, oxygen saturation, ventilation parameters, mucosal trauma, pulmonary aspiration, and Apgar scores. Differences between labor status were tested using Student's t-test, Mann-Whitney U test, or Fisher's exact test, as appropriate. Quantitative associations between labor status and outcomes were determined using univariate logistic regression analysis. RESULTS: Data from 584 parturients were analyzed, with 37.8% in labor. Labor did not significantly affect time to effective ventilation (mean (SD) for labor: 16.0 (5.75) seconds; no labor: 15.3 (3.35); mean difference: -0.65 (95%CI: - 1.49 to 0.18); p = 0.1262). However, labor was associated with increased first-attempt insertion failure and blood on sLMA surface. No reduction in oxygen saturation or pulmonary aspiration was noted. CONCLUSIONS: Although no significant increase in time to effective ventilation was noted, labor may increase the number of insertion attempts and oropharyngeal trauma with sLMA use for cesarean delivery in parturients at low risk of difficult airway. Future studies should investigate the effects of labor on LMA use in high risk parturients. TRIAL REGISTRATION: The study was prospectively registered at clinicaltrials.gov ( NCT02026882 ) on 3 January 2014.

Comparison of Supreme laryngeal mask airway versus endotracheal intubation for airway management during general anesthesia for cesarean section: a randomized controlled trial.

BACKGROUND: The obstetric airway is a significant cause of maternal morbidity and mortality. Endotracheal intubation is considered the standard of care but the laryngeal mask airway (LMA) has gained acceptance as a rescue airway and has been incorporated into the obstetric airway management guidelines. In this randomized controlled equivalence trial, we compared the Supreme LMA (SLMA) with endotracheal intubation (ETT) in managing the obstetric airway during cesarean section. METHODS: Parturients who underwent elective cesarean section under general anesthesia were randomized to receive either an SLMA or ETT as their airway device. Our primary outcome was first-attempt insertion success. Successful insertion was defined as adequate bilateral air entry with auscultation and the presence of end-tidal carbon dioxide on the capnogram. The first-attempt insertion success rate was compared using the Chi-Square test. Secondary outcomes included time-to-ventilation, seal pressure, ventilation/hemodynamic parameters, occurrence of clinical aspiration, fetal outcomes, and maternal side effects associated with the airway device. RESULTS: We recruited 920 parturients (460 SLMA, 460 ETT) who underwent elective cesarean section under general anesthesia. Patient characteristics were similar between the groups. First attempt success was similar (Odds Ratio--ORSLMA/ETT: 1.00 (95%CI: 0.25, 4.02), p = 1.0000). SLMA was associated with reduced time to effective ventilation (Mean Difference--MD -22.96; 95%CI: - 23.71, - 22.21 s) compared to ETT group (p <  0.0001). Ventilation parameters, maternal and fetal outcomes were similar between the groups, and there was no aspiration. CONCLUSIONS: SLMA could be an alternative airway management technique for a carefully selected low-risk obstetric population, with similar insertion success rates, reduced time to ventilation and less hemodynamic changes compared with ETT. Our findings are consistent with the airway guidelines in recommending the second-line use of LMA in the management of the obstetric airway. TRIAL REGISTRATION: The study was registered at http://www.clinicaltrials.gov , identifier: NCT01858467 , retrospectively registered. Date of registration: May 21, 2013.

Association of Mallampati scoring on airway outcomes in women undergoing general anesthesia with Supreme™ laryngeal mask airway in cesarean section.

BACKGROUND: Obstetric dfficult airway is a leading cause of maternal morbidity and mortality. The laryngeal mask airway (LMA) is often used as a rescue airway device after failed intubation, however, little is known about predictors of difficult LMA insertion, particularly in obstetrics. Since Mallampati scores of III/IV has been associated with difficult tracheal intubation, our present study aims to investigate if Mallampati score (MP) could predict airway outcomes for LMA use in obstetrics. METHODS: This prospective cohort study was performed at a single-center: Quanzhou Women's and Children's Hospital, Fujian Province, China. Five hundred and eighty-four parturients undergoing elective cesarean section under general anesthesia were recruited. The primary outcome was time to effective ventilation, and secondary outcomes included first attempt insertion success, seal pressure, ventilation and hemodynamic parameters, occurrence of clinical aspiration, and maternal and fetal outcomes. RESULTS: The parturients were classified into two groups based on MP of III/IV (High MP: 61) versus I/II (Low MP: 523). BMI was higher in the High MP group than in the Low MP group (mean (SD) 29.3 (7.0) vs 26.8 (3.1), p <  0.0001). There was no difference in maternal age, ASA status and gestational age. There was similar time to effective ventilation (mean (SD) High MP: 14.9 (4.5) vs Low MP: 15.7 (4.4) seconds, p = 0.2172), and first attempt success rate, seal pressure, and peak airway pressure. No clinical aspiration was noted. The incidence of blood on SLMA was higher in the High MP group than in Low MP (4 (6.6%) vs 4 (0.8%), p = 0.001). There was no difference in sore throat, voice hoarseness, maternal satisfaction and fetal outcomes. CONCLUSION: High MP was not associated with reduced SLMA airway outcomes in cesarean section under general anesthesia, but may increase the risk of blood found on SLMA upon removal. TRIAL REGISTRATION: This study was registered at http://www.clinicaltrials.gov , identifier: NCT02026882 , retrospectively registered. Date of registration: December 31, 2013.

Reducing breakthrough pain during labour epidural analgesia: an update.

PURPOSE OF REVIEW: Neuraxial techniques are the current gold standard for labour analgesia, but are associated with up to 25% incidence of breakthrough pain. In this review, we aim to update clinicians on the latest research pertaining to the optimization of neuraxial labour analgesia. RECENT FINDINGS: Attempts to improve the efficacy and reliability of epidural analgesia while minimizing adverse effects have resulted in the rising popularity of combined spinal epidural and the dural puncture epidural (DPE). Recent studies have focused on determining the safety, efficacy, and optimization of the DPE technique.Another research focus is on the development of individualized therapy in which patients may titrate their own labour analgesia according to their varying requirements, possibly augmented with computer-aided feedback systems and automated mandatory bolus techniques that automatically adjust drug delivery to the patients' analgesic requirements. The addition of a risk-stratification model based on maternal, anaesthetic, and obstetric factors will facilitate early institution of individualized therapy to forestall breakthrough pain in higher risk patients. SUMMARY: Recent advances in combined spinal epidural, DPE, automated mandatory bolus, and individualized therapies have advanced our goal of providing effective labour analgesia that is titrated to changing analgesic requirements during labour and delivery and reducing breakthrough pain.