Intravenous dexmedetomidine for the treatment of shivering during Cesarean delivery under neuraxial anesthesia: a randomized-controlled trial.

PURPOSE: About 55% of patients undergoing a Cesarean delivery under spinal or epidural anesthesia will experience shivering, which may interfere with the monitoring of vital signs. Recent studies have shown that dexmedetomidine could potentially help to alleviate shivering associated with anesthesia. We investigated whether dexmedetomidine, an alpha 2-adrenergic agonist, reduces the duration of shivering associated with neuraxial anesthesia during Cesarean delivery. METHODS: Eighty parturients undergoing Cesarean delivery under neuraxial anesthesia and experiencing shivering were enlisted in this prospective, randomized, double-blind trial. After childbirth, the intervention group (n = 40) received a single intravenous bolus of dexmedetomidine (30 µg) while the control group (n = 40) received saline. Randomization and allocation were based on a computer-generated list. The primary outcome measure was the time required for an observable decrease in shivering after the intervention. RESULTS: One hundred fifty-five patients were recruited, 80 of whom presented with shivering and were randomized. Our study showed that dexmedetomidine reduced the mean (standard deviation) duration of shivering after a single intravenous bolus to 2.6 (2.1) min after dexmedetomidine from 17.9 (12.6) min after saline (difference in means, -15.3 min; 95% confidence interval [CI], -11.2 to -19.4). The effect of dexmedetomidine persisted 15 min after the bolus was administered, as shivering had completely stopped in 90% of the patients in the intervention group vs 22.5% in the control group (relative risk, 4.0; 95% CI, 2.2 to 7.2). No adverse effects, including bradycardia, were observed. CONCLUSION: A single intravenous bolus of dexmedetomidine decreased the duration of shivering for up to 15 min during Cesarean delivery under neuraxial anesthesia. TRIAL REGISTRATION: www.clinicaltrials.gov (NCT02384343); registered 10 March, 2015.

RéSUMé: OBJECTIF: Environ 55 % des patientes subissant un accouchement par césarienne sous anesthésie rachidienne ou épidurale vont manifester des frissons, lesquels peuvent interférer avec la mesure des signes vitaux. Des études récentes ont démontré que la dexmédétomidine a le potentiel de réduire les frissons associés à l'anesthésie. Nous avons cherché à démontrer si la dexmédétomidine, un agoniste des récepteurs alpha-2-adrénergiques, peut réduire la durée des frissons associés à l'anesthésie neuraxiale lors d'un accouchement par césarienne. MéTHODE: Quatre-vingts parturientes subissant un accouchement par césarienne sous anesthésie neuraxiale et manifestant des frissons ont été recrutées pour cette étude prospective, randomisée et à double insu. Après la naissance, le groupe intervention (n = 40) a reçu un bolus intraveineux unique de dexmédétomidine (30 µg) alors que le groupe témoin (n = 40) a reçu une solution saline. La randomisation et l'attribution ont suivi une liste générée par ordinateur. Le critère d'évaluation principal était le temps nécessaire avant d'observer une réduction des frissons après l'intervention. RéSULTATS: Cent cinquante-cinq patientes ont été recrutées, dont 80 ont présenté des frissons et ont été randomisées. Notre étude a montré que la dexmédétomidine réduisait la durée moyenne (écart type) des frissons après un bolus intraveineux unique à 2,6 (2,1) min après l'administration de dexmédétomidine par rapport à une durée moyenne de 17,9 (12,6) min après la solution saline (différence de moyennes, -15,3 min; intervalle de confiance [IC] 95 %, -11,2 à -19,4). L'effet de la dexmédétomidine persistait 15 min après l'administration du bolus, où les frissons avaient complètement cessé chez 90 % des patientes du groupe intervention vs 22,5 % du groupe témoin (risque relatif, 4,0; IC 95 %, 2,2 à 7,2). Aucun effet secondaire néfaste, y compris la bradycardie, n'a été observé. CONCLUSION: Un bolus intraveineux unique de dexmédétomidine réduit la durée des frissons jusqu'à 15 min lors d'un accouchement par césarienne sous anesthésie neuraxiale. ENREGISTREMENT DE L'éTUDE: www.clinicaltrials.gov (NCT02384343); enregistrée le 10 mars 2015.

Nonpharmacologic approaches for pain management during labor compared with usual care: a meta-analysis.

OBJECTIVES: To assess the effects of nonpharmacologic approaches to pain relief during labor, according to their endogenous mechanism of action, on obstetric interventions, maternal, and neonatal outcomes. DATA SOURCE: Cochrane library, Medline, Embase, CINAHL and the MRCT databases were used to screen studies from January 1990 to December 2012. STUDY SELECTION: According to Cochrane criteria, we selected randomized controlled trials that compared nonpharmacologic approaches for pain relief during labor to usual care, using intention-to-treat method. RESULTS: Nonpharmacologic approaches, based on Gate Control (water immersion, massage, ambulation, positions) and Diffuse Noxious Inhibitory Control (acupressure, acupuncture, electrical stimulation, water injections), are associated with a reduction in epidural analgesia and a higher maternal satisfaction with childbirth. When compared with nonpharmacologic approaches based on Central Nervous System Control (education, attention deviation, support), usual care is associated with increased odds of epidural OR 1.13 (95% CI 1.05-1.23), cesarean delivery OR 1.60 (95% CI 1.18-2.18), instrumental delivery OR 1.21 (95% CI 1.03-1.44), use of oxytocin OR 1.20 (95% CI 1.01-1.43), labor duration (29.7 min, 95% CI 4.5-54.8), and a lesser satisfaction with childbirth. Tailored nonpharmacologic approaches, based on continuous support, were the most effective for reducing obstetric interventions. CONCLUSION: Nonpharmacologic approaches to relieve pain during labor, when used as a part of hospital pain relief strategies, provide significant benefits to women and their infants without causing additional harm.

Failed epidural analgesia in a parturient with advanced ankylosing spondylitis: a novel explanation.

PURPOSE: Ankylosing spondylitis (AS) is a chronic progressive multisystemic disease. Patients with AS present a specific set of anesthesia-related challenges, and the parturient with AS presents particular anesthetic considerations. We report our experience with a parturient with advanced AS and offer a novel explanation for the high incidence of epidural failures in this patient population. CLINICAL FEATURES: We present the case of a 36-yr-old primigravida parturient with a very difficult airway and a history of severe AS. The initial treatment plan was to use a continuous epidural for labour analgesia. Despite two successful placements of lumbar epidural catheters, adequate rostral spread of local anesthesia to control her labour pain was never achieved via the epidural route. Thus, continuous spinal anesthesia was used, which provided effective labour analgesia in this patient. CONCLUSION: We hypothesize that this patient's advanced calcified posterior longitudinal ligament caused a physical barrier to rostral spread of local anesthesia solution within her epidural space. This hypothesis is supported by a recent study highlighting the importance of this ligament in allowing adequate distribution of solution within the epidural space. In addition, the successful use of continuous spinal analgesia adds to the growing body of literature supporting the safety and efficacy of intrathecal catheters for labour analgesia in specific situations.

Obstetric emergencies.

Obstetric hemorrhage is still a significant cause of maternal morbidity and mortality. Prevention, early recognition, and prompt intervention are the keys to minimizing complications. Resuscitation can be inadequate because of under-estimation of blood loss and misleading maternal response. A young woman may maintain a normal blood pressure until sudden and catastrophic decompensation occurs. All members of the obstetric team should know how to manage hemorrhage because timing is of the essence. Good communication with the blood bank ensures timely release of appropriate blood products. A well-coordinated team is one of the most important elements in the care of a compromised fetus. If fetal anoxia is presumed, there is less than 10 minutes to permanent fetal brain damage. Antepartum anesthesia consultation should be encouraged in parturients with medical problems.