Arrhythmias during spinal anesthesia for Cesarean section

Abstract

Purpose: Spinal block has long been considered a safe anesthesia technique for surgery. However, severe bradycardia, cardiac arrest, and other arrhythmias during spinal anesthesia have been reported and the incidence of intraoperative arrhythmias is not well established. In this study the incidence of arrhythmias during spinal anesthesia was determined. Methods:We studied 254 healthy women undergoing Cesarean section under spinal anesthesia prospectively. Spinal anesthesia with 10 mg bupivacaine mixed with 0.2 mg morphine was performed at the L 3-4 interspace. Intraoperative arrhythmias were recorded and verified later by a cardiologist.Results: First degree atrioventricular block developed in nine patients (3.5%), second degree atrioventricular block in nine (3.5%), severe bradycardia (heart rate < 50 beats·min -1 ) in seventeen (6.7%), multiple VPC in three (1.2%). The height and weight of patients with severe bradycardia, multiple VPCs, or atrioventricular block were not different from those of the other patients. However, the age of patients in the potentially dangerous arrhythmias group was greater than that in the other group (P = 0.006). Conclusion:The incidence of arrhythmias as well as hypotension during spinal anesthesia for Cesarean section was higher than expected. Although most of these arrhythmias were transient and recovered spontaneously, they might unexpectedly occur and sometimes need immediate and prompt treatment. It is necessary to remain vigilant during spinal anesthesia for Cesarean section and careful monitoring of these patients is warranted, especially in older parturients.Objectif : On a longtemps considéré la rachianesthésie comme une technique sécuritaire pour la chirurgie. Cependant, des cas de bradycardie sévère, d'arrêt cardiaque et d'autres arythmies ont été signalés pendant la rachianesthésie et l'incidence d'arythmie peropératoire n'est pas bien définie. Dans la présente étude, on a déter-miné l'incidence d'arythmie pendant la rachianesthésie.Méthode : Nous avons fait l'étude prospective de 254 femmes en santé qui ont subi une césarienne sous rachianesthésie. L'injection de 10 mg de bupivacaïne avec 0,2 mg de morphine a été réalisée dans l'espace L 3-4 . L'arythmie peropératoire a été notée et vérifiée ensuite par un cardiologue.Résultats : Un bloc auriculoventriculaire de premier degré s'est développé chez neuf patientes (3,5 %), un bloc de second degré chez neuf patientes également (3,5 %), une bradycardie sévère (fréquence cardiaque < 50 battements·min -1 ) chez dix-sept (6,7 %), de multiples ESV chez trois (1,2 %). La grandeur et le poids des patientes qui ont présenté une bradycardie sévère, de multiples ESV ou un bloc auriculoventriculaire ne différaient pas de ceux des autres patientes. Toutefois, les patientes du groupe présentant des arythmies potentiellement dangereuses étaient plus âgées que les autres (P = 0,006).Conclusion : L'incidence d'arythmie autant que d'hypotension pendant la rachianesthésie pour une césarienne a été plus élevée que prévu. Même si la plupart...

Evidence-Based Obstetric Anesthesia: An Update on Anesthesia for Cesarean Delivery

“…The investigators speculated that a relative increase in parasympathetic activity occurred as a result of spinal blockade of cardiac sympathetic activity. Most of the dysrhythmias were transient and resolved spontaneously [63]. However, prompt management with vasoactive drugs should be performed if dysrhythmias persist.…”

Arrhythmias during spinal anesthesia

“…fournissent de nouvelles informations dans leur article sur les arythmies qui surviennent pendant les césariennes. 3 Les chercheurs ont procédé à l'étude prospective de 254 femmes. Ils ont réalisé des blocages sensitifs qui se situaient, au maximum, de T 7 à C 7 en utilisant une dose sous-arachnoïdienne fixe de bupivacaïne et de morphine.…”

“…There are reports of 1st and 2nd degree heart block, 3,20,21 1st degree progressing to 2nd degree heart block 2 2 and complete heart block 12,14 after spinal anesthesia. In eight of the nine patients who developed second-degree heart block in Shen's study, the arrhythmia had a temporal association with at least one stimulus that could have led to increased vagal tone.…”

“…2 In this issue of the journal, Shen et al further add to our understanding of this topic in their report on arrhythmias occurring during Cesarean sections. 3 The investigators studied 254 healthy women prospectively. They achieved peak sensory levels in the range of T 7 to C 7 using a fixed dose of subarachnoid bupivacaine and morphine.…”

The role of the autonomic nervous system in acute surgical pain processing - what do we know?

“…However, daily experience, especially as far as the cardiovascular system is concerned, tells us that modulation of one part of the autonomic nervous system subsequently also affects the other [19]. Therefore, it might be reasonable to assume similar interactions for the sensory function of the autonomic nervous system as well.…”