Elizabeth Bell

Iliohypogastric-ilioinguinal peripheral nerve block for post-Cesarean delivery analgesia decreases morphine use but not opioid-related side effects

PurposeTo examine if ilioinguinal-iliohypogastric nerve block could reduce the need for post-Cesarean delivery morphine analgesia and thus reduce the incidence of opioid related adverseeffects.MethodsA multi-level technique for performing the nerve block with bupivacaine was developed and then utilized in this two-part study. Part one was a retrospective assessment of Cesarean delivery patients with and without ilioinguinal-iliohypogastric blocks to determine if the technique reduced patient controlled analgesia morphine use and thus would warrant further study. The second phase was a randomized double-blind placebo-controlled trial to compare post-Cesarean morphine use and the appearance of opioid-related side effects between the anesthetic and placebo-injected groups.ResultsBoth phases demonstrated that our method of ilioinguinaliliohypogastric nerve block significantly reduced the amount ofiv morphine used by patients during the 24 hr following Cesarean delivery. In the retrospective assessment, morphine use was 49 ± 30 mg in the block groupvs 79 ± 25 mg in the no block group (P = 0.0063). For the prospective trial, patients who received nerve blocks with bupivacaine had a similar result, self-administering 48 ± 27 mg of morphine over 24 hr compared to 67 ± 28 mg administered by patients who received infiltrations of saline. However, despite the significant decrease in morphine use, there was no reduction in opioid-related adverse effects: the incidences of nausea were 41 % and 46% (P = 0.70) and for itching were 79% and 63% (P = 0.25) in the placebo and nerve block groups, respectively.ConclusionA multi-level ilioinguinal-iliohypogastric nerve block technique can reduce the amount of systemic morphine required to control post-Cesarean delivery pain but this reduction was not associated with a reduction of opioid related adverse effects in our study group.RésuméObjectifVérifier si l’anesthésie par blocage nerveux ilioinguinal et iliohypogastrique peut réduire ies besoins postcésarienne de morphine et l’incidence des effets indésirables des opioïdes.MéthodeUne technique de blocage nerveux multiniveau, avec de la bupivacaïne, a été mise au point et utilisée pour une étude en deux phases. La première consistait en une évaluation rétrospective des accouchements par césarienne avec et sans biocages ilioinguinal et iliohypogastrique dans le but de déterminer si la technique réduit l’usage de morphine autoadministrée, ce qui pourrait justifier des études plus poussées. La seconde phase était un essai, randomisé et contrôlé en double aveugle contre placebo, réalisé pour comparer l’usage intergroupe de morphine postcésarienne et l’apparition d’effets secondaires reliés aux opioïdes.RésultatsPour les deux phases de l’étude, l’anesthésie par blocage nerveux ilioinguinal et iliohypogastrique a permis de réduire significativement la quantité de morphine iv utilisée pendant les 24 premières heures suivant la césarienne. Dans l’évaluation rétrospective, la morphine utilisée a été de 49 ± 30 mg chez les patientes qui ont reçu un bloc vs 79 ± 25 mg, sans bloc (P = 0,0063). Les résultats de l’essai prospectif sont comparables, l’autoadministration de morphine pendant 24 h étant de 48 ± 21 mg et de 67 ± 28 mg avec et sans bupivacaïne, respectivement. Cependant, il n’y a pas eu de réduction des effets indésirables reliés aux opioïdes: les incidences de nausée ont été de 41 % et de 46 % (P = 0,70) et de prurit, 79 % et 63 % (P = 0,25) chez les patientes avec placebo et bloc nerveux, respectivement.ConclusionUn blocage nerveux ilioinguinal et iliohypogastrique a permis de réduire la quantité de morphine à action générale utilisée pour soulager la douleur postcésarienne, mais cette réduction n’a pas été associée à une baisse des effets secondaires reliés aux opioïdes.

SvO(2) Monitoring during Spinal Anesthesia and Cesarean Section in a Parturient with Severe Cyanotic Congenital Heart Disease

ADVANCES in palliative and corrective cardiovascular surgical procedures have lead to increasing numbers of patients with congenital heart disease in the obstetric population. 1 We describe a parturient with palliated complex congenital heart disease. Our peripartum treatment of this challenging patient included mixed venous oximetry and continuous spinal anesthesia.

Use of an Automated Anesthesia Information System to Determine Reference Limits for Vital Signs During Cesarean Section

Introduction. We evaluated whether automated anesthesia information systems can be used to calculate reference limits (population-based “normal values”) for vital signs. We considered four populations of women undergoing cesarean section: healthy under spinal anesthesia, healthy under general anesthesia, pre-eclamptic/eclamptic under spinal anesthesia, and pre-eclamptic/eclamptic under general anesthesia. Methods. Reference limits were calculated for each of the study populations by determination of percentiles for: minimum heart rate, maximum heart rate, minimum arterial oxyhemoglobin saturation (SaO2), minimum mean arterial pressure (MAP), maximum MAP, decrease in MAP, and increase in MAP. Results.There was one adverse anesthetic outcome among the 1,300 women in the study; the woman sustained a post-dural puncture headache. The 5th percentiles of SaO2 were at least 95% saturation under spinal versus90% under general. Under spinal anesthesia, 95th percentiles for decreases in MAP from baseline were 63 mmHg for healthy and 75 mmHg for pre-eclamptic/eclamptic women. Under general anesthesia, the 95th percentiles for maximum MAP were 161 and 177 mmHg, respectively. Two women of the 1,300 patients experienced simultaneously a minimum SaO2 <92% and minimum MAP <50 mmHg. Discussion. Automated anesthesia information systems can be used to determine reference limits for vital signs during anesthesia. Reference limits may play a role in malpractice cases when an expert claims that care by an anesthesiologist was sub-standard as shown by vital signs that were not maintained within the normal range during the critical portions of an anesthetic. Automated anesthesia information systems may enhance expert witnesses’ clinical judgment.