Critical alkalosis following intraperitoneal irrigation with sodium bicarbonate in a patient with pseudomyxoma peritonei.

Pseudomyxoma peritonei (PMP) is a rare disease, presenting with large amounts of mucinous ascites, and treatment with intraperitoneal irrigation with mucolytic agents has been tried. We report a patient with PMP who underwent intraperitoneal irrigation with sodium bicarbonate and exhibited marked alkalosis. The patient was a 78-year-old woman who had mucinous ascites, and an appendiceal and an ovarian tumor. Bilateral salpingo-oophorectomy and appendectomy were performed, and she then underwent intraperitoneal irrigation with sodium bicarbonate (7%, 1000 ml). Shortly after the irrigation, blood gas analysis showed critical alkalosis (pH, 7.66; base excess [BE], 24 mEq x l(-1); HCO3 (-), 50 mEq x l(-1)) with electrolyte imbalance (Na+, 153 mEq x l(-1); K+, 2.8 mEq x l(-1); Ca2+, 0.98 mEq x l(-1), Cl(-1), 99 mEq x l(-1)). The alkalosis and electrolyte imbalance were ameliorated with the administration of potassium chloride and calcium chloride intravenously, and the patient was extubated after the 2-h surgical procedure. The patient was discharged home after 15 days without problems. Sodium bicarbonate may be an effective mucolytic agent for PMP. However, during irrigation with sodium bicarbonate, careful evaluation of the acid-base balance and serum electrolytes, and prompt treatment of alkalosis or electrolyte imbalance, should this occur, are of great importance.