Reactions 1316 - 28 Aug 2010

SMagnesium citrate/magnesium oxide

Hypermagnesaemia and perforative peritonitisleading to shock, in an elderly patient: casereport

A 79-year-old woman developed hypermagnesaemiaand perforative peritonitis leading to shock duringtreatment with magnesium citrate and magnesium oxide[routes and times to reaction onsets not stated].

The woman, who had a history of hysterectomy formyoma, was receiving magnesium oxide 750 mg/day forconstipation [duration of therapy not stated]. Duringcommunity screening, she was found to have bloody stool.She was subsequently scheduled to undergo acolonoscopy. She received magnesium citrate 34mg(MAGCOROL-P) as part of her pretreatment. Shedeveloped muscle weakness, nausea and progressivelyworsening consciousness. She was taken to hospital by anambulance. On arrival, she had a BP of 95/33mm Hg, an HRof 84 beats/minute, an RR of 24 breaths/minute, a bodytemperature of 36.7°C and a Glasgow coma scale score of13. She reported left abdominal pain, prompting suspicionof peritonitis.

The woman received antibiotics. However, her bloodpressure continued to decreased and she went into shock.She received norepinephrine [noradrenaline], dobutamineand vasopressin; however, her BP remained about60/30mm Hg and her HR was 80–90 beats/minute. Herconsciousness decreased further and she was intubatedand ventilated. X-ray and CT scan showed intestinalobstruction; she was diagnosed with shock due tointestinal perforative peritonitis, and was scheduled forexploratory laparotomy. On entering the operating room,she had a BP of 40/20mm Hg and an oxygen saturation of90%. Metabolic acidosis was evident, and she had anelevated ionised Mg level of 2.75 mmol/L. There were noobvious signs of perforation, but her ascites were turbid.Her previous surgery had led to intestinal obstruction. Itwas deduced that laxative ingestion had increased theinternal intestinal pressure causing micro-perforations. Atthe same time, she developed shock andhypermagnesaemia due to Mg absorption by the intestinalcanal or peritoneum. She received calcium chloride,furosemide, high-volume fluid and sodium bicarbonate.Her BP, HR and findings on blood gas analysis improved.Following surgery, she was transferred to the ICU andimmediately started continuous haemodiafiltration; sherequired norepinephrine and vasopressin. Her Mg levelreached 11.4 mg/dL but gradually normalised; hercirculation dynamics also began to stabilise. She wastransferred to ward on day 15. She had mild motorimpairment in her left upper and lower extremities due to abrain infarction believed to have resulted from intracranialcirculation failure during shock. She was discharged onday 84 without any other major problem.Kikuchi T, et al. Perioperative management for a patient with hypermagnesemia-induced shock with perforative peritonitis. Journal of Anesthesia 24: 479-481, No.3, Jun 2010. Available from: URL: http://dx.doi.org/10.1007/s00540-010-0909-2 -Japan 803034947

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Reactions 28 Aug 2010 No. 13160114-9954/10/1316-0001/$14.95 © 2010 Adis Data Information BV. All rights reserved