Total intravenous anaesthesia in a patient with familial hypokalaemic periodic paralysis*

Abstract

A 35-year-old woman with known familial hypokalaemic periodic paralysis received general anaesthesia for reduction of bilateral breast hyperplasia. Uncomplicated general anaesthesia was performed using a propofol target-controlled infusion, remifentanil infusion and bolus doses of mivacurium with neuromuscular function monitoring. Plasma potassium concentrations were controlled intermittently in the peri-operative period and supplemented to achieve normokalaemia. Despite continuous substitution, an episode of low plasma potassium concentration occurred during the recovery period; this was without any clinical signs of muscle paralysis or respiratory distress.

Diverse phenotype of hypokalaemic periodic paralysis within a family

“…Perioperative potassium homeostasis is an essential part of their management 24. Neuromuscular blocking agents are not advisable because postoperative muscle weakness can occur after receiving depolarising neuromuscular agents 25 26.…”

Hypokalemic periodic paralysis

“…Hypokalemic familial periodic paralysis is a rare channelopathy with muscle weakness and a matching fall in the potassium levels in the blood; it is a autosomal dominant genetic disorder[1] in the gene encoding for the dihydropyridine sensitive calcium channel. [2] The weakness may be limited to muscle groups or may present as severe muscle paralysis.…”

Pathophysiologic and anesthetic considerations for patients with myotonia congenita or periodic paralyses

“…Therefore, although HypoPP is genetically heterogenous, there seems to be a high likelihood that this patient had two mutations, one for HypoPP and one for MH. Still, as long as formal proof of this is lacking, it seems advisable to use MH trigger‐free anesthetic methods in HypoPP patients to avoid eventually hypermetabolic events . Nevertheless, another careful consideration for anesthetic management of such affected patients is to prevent the induction of perioperative episodes of muscle weakness; for example, this implies avoiding large glucose and salt loads, maintaining normothermia, keeping serum potassium levels in the normal upper range, maintaining controlled hypercapnia (pCO 2 about 40 mmHg) to avoid alkalosis, as well as reducing the given patients' anxiety .…”