Fatal Hyperkalemia Following Reduction of a Strangulated Obturator Hernia: A Pitfall in Assessing Bowel Viability.

INTRODUCTION: Obturator hernia is a rare cause of small-bowel obstruction and is frequently associated with strangulation. Even after successful reduction, bowel ischemia-reperfusion injury may occur and result in life-threatening metabolic complications. CASE PRESENTATION: An 87-year-old woman presented with a 3-week history of nausea and vomiting. CT revealed a right obturator hernia with incarceration of a small-bowel loop. US-guided manual reduction was successfully performed. Contrast-enhanced CT obtained immediately after reduction demonstrated preserved bowel-wall enhancement with circumferential mural thickening. The serum potassium level at presentation was 4.6 mmol/L. Despite apparently preserved bowel perfusion on CT, she continued to experience abdominal pain, tachypnea, and progressively deteriorating consciousness. Approximately 5 h after reduction, she developed sudden bradycardia followed by cardiac arrest. Continuous electrocardiographic monitoring showed progression from sinus rhythm to loss of P waves, QRS widening, and finally a sine-wave pattern. Laboratory testing during resuscitation revealed severe hyperkalemia (8.5 mmol/L). Despite intensive resuscitative efforts, the patient died. CONCLUSIONS: Preserved bowel-wall enhancement after reduction of a strangulated obturator hernia does not necessarily indicate bowel viability. A prolonged clinical course, persistent symptoms or systemic abnormalities, and residual CT abnormalities such as bowel-wall thickening and ascites should be considered together when assessing bowel viability after reduction. Such findings should prompt careful reassessment, close monitoring, and consideration of early surgical exploration despite preserved bowel-wall enhancement.