# Severe Post-spinal Bezold-Jarisch Reflex During Emergency Caesarean Delivery Unmasking Wolff-Parkinson-White Pattern

## TL;DR

A woman undergoing emergency caesarean delivery developed severe hypotension and bradycardia, revealing a previously undiagnosed heart condition.

## Contribution

This case highlights how spinal anesthesia can unmask underlying cardiac conduction abnormalities like Wolff-Parkinson-White syndrome.

## Key findings

- Spinal anesthesia-induced hypotension can progress to profound bradycardia consistent with the Bezold-Jarisch reflex.
- Adrenergic and anticholinergic therapy may reveal undiagnosed Wolff-Parkinson-White patterns during hemodynamic stress.
- Proactive blood pressure management is emphasized in obstetric vasopressor guidelines to prevent such complications.

## Abstract

Spinal anaesthesia for caesarean delivery commonly causes maternal hypotension due to sympathetic blockade and may occasionally progress to profound bradycardia with haemodynamic collapse when venous return is markedly reduced. We report the case of a 34-year-old gravida 3 para 2 woman at 36 weeks of gestation who underwent emergency caesarean delivery under single-shot spinal anaesthesia. Shortly after the onset of the block, she developed significant hypotension, which rapidly progressed to profound hypotension with marked bradycardia, producing a clinical picture consistent with the Bezold-Jarisch reflex (BJR). After stabilisation, transient rhythm irregularity with intermittent ectopy was observed, without sustained tachyarrhythmia or supraventricular tachyarrhythmia. The rhythm disturbance was benign and self-limited. Postoperatively, a 12-lead electrocardiogram demonstrated a previously undiagnosed Wolff-Parkinson-White (WPW) pattern, and cardiology follow-up was arranged.

This case highlights (i) the frequency and clinical significance of spinal anaesthesia-induced hypotension during caesarean delivery, (ii) the potential for bradycardic-hypotensive episodes consistent with BJR or vasovagal physiology when venous return is compromised, and (iii) how adrenergic and anticholinergic rescue therapy (ephedrine and atropine), together with physiological stress, may unmask underlying cardiac conduction abnormalities such as WPW.

Current obstetric vasopressor guidelines emphasise proactive blood pressure maintenance, typically using a prophylactic phenylephrine infusion initiated immediately after intrathecal injection in combination with crystalloid co-loading, with rescue vasopressors titrated according to maternal haemodynamics. For newly identified WPW, contemporary recommendations support risk stratification, including assessment for intermittent pre-excitation, and consideration of electrophysiological evaluation and catheter ablation when clinically indicated.