Cola-colored dialysate as a gastrointestinal sequelae of cardiac surgery in a patient who underwent peritoneal dialysis.

The discoloration of effluent peritoneal dialysate, which is transparent in origin, is seen in some particular conditions including chyloperitoneum, calcium channel blocker usage, hemoperitoneum, perforated cholecystitis, iron administration, and hemorrhagic pancreatitis. We report a case of a 60-year-old woman who underwent peritoneal dialysis for 3 years and presented with conspicuous cola-colored (brownish-black) dialysate after a cardiac surgery. The findings of the dialysate analysis and the abdominal computed tomography showed that this discoloration could be due to the presence of methemalbumin caused by pancreatitis (not hemorrhagic) combined with intra-abdominal bleeding-both of which are rare gastrointestinal complications of cardiac surgery. She eventually died of pulseless electrical activity due to severe sepsis with profound shock. Therefore, the rare event of cola-colored peritoneal dialysate could present as severe gastrointestinal sequelae of cardiac surgery and may indicate a poor prognosis.

The degradation of haem by carbon tetrachloride: metabolic activation requires a free axial coordination site on the haem iron and electron donation.

1. The ability of haem to catalyse the reductive activation of carbon tetrachloride (CCl4) in vitro has been investigated under anaerobic conditions, using methaemalbumin (MHA) and either sodium dithionite or NADPH together with NADPH-cytochrome P-450 reductase (EC 1.6.2.4) as the reducing agents. 2. In the non-enzymic system protohaem and other non-physiological haem analogues underwent rapid and extensive CCl4-dependent degradation, due to irreversible modification of their porphyrin tetrapyrrolic structure. 3. This mechanism of non-enzymic activation of CCl4 by protohaem mimics that catalyzed by cytochrome P-450 in that it requires a free, reduced haem iron and electron donation and it is largely prevented by carbon monoxide. 4. H.p.l.c. analysis of 14C-haem after anaerobic incubation with CCl4 and sodium dithionite gave radioactive products which eluted before and after haem, and exhibited significantly lower absorbance at 400 nm compared with authentic haem. When the products of CCl4-dependent haem degradation were methylated and applied to silica for t.l.c., two non-fluorescent pigments were isolated, purified and partially characterized. 5. On incubation of haem with 14CCl4 and sodium dithionite a 1:1 stoichiometry could be calculated for haem loss and 14CCl4-derived adduct formation, indicating that, as with microsomes, the loss of haem may be the result of a typical 'suicidal' inactivation reaction where the same haem moiety is both the site of CCl4 activation and the target of CCl4 reactive metabolites.