Delayed Bradycardia and Hypotension After Cervical Dorsal Root Ganglion and Occipital Pulsed Radiofrequency: A Single-Patient Observational Case Study

Abstract

Background Pulsed radiofrequency (PRF) is a non-destructive neuromodulation option for chronic cervical radiculopathy and occipital neuralgia, with an excellent safety record. Delayed neuro-autonomic collapse is poorly described.

Objective To describe the timing, hemodynamic course and possible mechanisms of delayed vasovagal-type syncope after fluoroscopy-guided cervical dorsal root ganglion (DRG) and occipital PRF.

Methods A 41-year-old woman had intractable cervical radiculopathy (C3–C6), tension-type headache, a history of cluster headache, vertigo and hypertension treated with amlodipine. She received fluoroscopy-guided PRF (120 s, 2 Hz, 45 V, ≤42 °C) at the bilateral C3 and C4 DRG and the greater and lesser occipital nerves. Hemodynamics and the Glasgow Coma Scale (GCS) were recorded for up to six weeks, and causality was appraised with three frameworks.

Results The procedure was uneventful. About 20 hours later the patient collapsed, with GCS 12 (E3V3M6), sinus bradycardia (58 bpm, −27.50%), hypotension (102/62 mmHg; mean arterial pressure 75.33 mmHg, −30.04%). Trendelenburg positioning, crystalloid and atropine were followed by gradual recovery: GCS 13 at one hour, 14 at seven hours and 15 by the next morning, without sequelae. Cardiac and metabolic causes were excluded. The Naranjo score was 7 (probable), but the scale is not validated for one procedural event. Radicular pain was NRS 1–2 at 14 days, and analgesia was sustained at six weeks.

Conclusion Upper cervical and occipital PRF may be followed by severe, delayed reflex-type collapse, possibly through trigeminocervical convergence and sympathetic withdrawal; the mechanism was not measured. Longer observation may be considered in susceptible patients.