Remifentanil at induction of general anesthesia for cesarean section: Double blind, randomized clinical trial

Introduction: Remifentanil, with its rapid activity onset and short duration of action, may be more effective than other opioids for providing hemodynamic stability during obstetric anesthesia. However, there is some evidence of adverse effects on neonatal respiratory function. We investigated maternal and fetal effects of remifentanil during cesarean section surgery. Methods: Eighteen women with singleton term pregnancies, and physical class status of I or II as defined by the American Society of Anesthesia (ASA), who were undergoing general anesthesia for semi-elective cesarean section were randomized into two groups (40 in each group) that received either an intravenous bolus of 0.5 µg/kg remifentanil or the same dose of saline as a placebo. Maternal hemodynamic variables and neonatal umbilical artery pH and Apgar score at first and fifth minutes were evaluated in both groups. Results: Systolic and diastolic blood pressure were significantly lower after tracheal intubation and skin incision in the remifentanil group as compared with the control group (p 0.05). Apgar scores at first and fifth minutes were not significantly different among groups (p>0.05). No neonate required assisted ventilation or naloxan administration. Conclusion: Remifentanil may be a safe and effective drug for the induction of general anesthesia and surgical stimulation without subsequent neonatal depression. Introducción: El remifentanilo, con su rápido comienzo de actividad y corta duración de acción, puede ser más eficaz que otros opioides para proporcionar la estabilidad hemodinámica durante la anestesia obstétrica. Sin embargo, hay alguna evidencia de efectos adversos sobre la función respiratoria neonatal. Se investigaron los efectos maternos y fetales de remifentanilo durante la cirugía cesárea. Métodos: Dieciocho mujeres con embarazo de feto uno y con clasificación Asa I o II (sociedad americana de anestesiología y que fueron sometidas a anestesia general para cesárea semi eletiva, se dividieron aleatoriamente en dos grupos (40 mujeres en cada grupo) que recibieron un bolo intravenoso de 0.5 mm/Kg de remifentanil o en el grupo control la misma dosis de solución salina como placebo.. Se evaluaron las variables hemodinámicas maternas y pH de la arteria umbilical neonatal y la puntuación de Apgar al primer y quinto minuto en ambos grupos. Resultados: La presión arterial sistólica y