Should nicorandil infusion be adapted in dialysis-dependent patients undergoing continuous renal replacement therapy after cardiac surgery?

In this report, we studied whether plasma concentration of nicorandil is maintained effectively and safely in dialysis-dependent patients with stage 5 chronic kidney disease (CKD5D) undergoing continuous renal replacement therapy (CRRT). Participants consisted of 10 patients undergoing CRRT after cardiac surgery. CRRT was performed with an effluent flow rate of either 600 mL/h (low-flow group; n = 5) or 1800 mL/h (high-flow group; n = 5). Nicorandil was infused intravenously at 0.1 mg/kg/h for more than 15 h starting 8 h before and 7 h after the start of CRRT. Plasma nicorandil concentrations were measured from arterial blood lines 1 h before and 7 h after CRRT initiation. Nicorandil clearance by CRRT was also calculated 1 h after CRRT initiation. Nicorandil plasma concentrations before and 7 h after CRRT initiation were 68.0 ng/mL and 74.6 ng/mL, respectively. Nicorandil clearance 1 h after CRRT initiation was 20.2 mL/min. Increasing the effluent flow rate from 600 mL/h to 1800 mL/h tended to increase nicorandil clearance. When nicorandil was infused intravenously during CRRT at 0.1 mg/kg/h in patients with CKD5D, plasma nicorandil concentrations were maintained within an effective concentration range.

Effect of hemopurification rate on doripenem pharmacokinetics in critically ill patients receiving high-flow continuous hemodiafiltration.

  Hemopurification is an effective therapy for acute kidney injury, defined as creatinine clearance less than 30 ml/min, which occurs frequently in the intensive care unit. These critically ill patients often have severe infectious complications and are thus often treated with antibiotics. However, the effect of hemopurification on the pharmacokinetics of antibiotics is not well understood. In this study, we investigated the pharmacokinetics of doripenem (DRPM) in critically ill patients with accompanying renal dysfunction undergoing continuous hemodiafiltration by high-volume filtration/high-flow dialysis (high-flow CHDF) and compared it to the pharmacokinetics of DRPM during conventional CHDF. We studied 8 patients (2 in the high-flow group and 6 in the conventional group) in whom DRPM was administered while performing CHDF for acute kidney injury. DRPM (250 mg) was intravenously infused over 1 h. For the conventional group, CHDF was performed at a blood flow rate (Q(B)) of 100 ml/min, dialysate flow rate (Q(D)) of 500 ml/h, and filtration flow rate (Q(F)) of 300 ml/h. For the high-flow group, CHDF was performed at a blood flow rate (Q(B)) of 100 ml/min, dialysate flow rate (Q(D)) of 1500 ml/h, and filtration flow rate (Q(F)) of 900 ml/h. For both groups, a polysulfonehemofilter with a membrane area of 1.0 m(2) was used. Mean half-life, total body clearance, and clearance via hemodiafiltration of DRPM were 2.9 h, 118 ml/min, and 41.9 ml/min, respectively, in the high-flow group, and 7.9 h, 58 ml/min, and 13.5 ml/min in the conventional group. Clearance via hemodiafiltration increased approximately 3-fold by tripling the hemopurification rate. Therefore, CHDF parameters greatly affected DRPM pharmacokinetics in patients receiving CHDF. These results suggest that clearance via hemodiafiltration increases proportionally to the hemopurification rate. Thus, it is reasonable to conclude that DRPM dose must be increased to 1.0-1.5 g/day when performing high-flow CHDF.

[New technique for identification of the pulmonary segment using high frequency jet ventilation and bronchofiberscopy].

We report a simple and quick technique for the identification of the pulmonary segment using high frequency jet ventilation and bronchofiberscopy. During the pulmonary segmentectomy, we inserted a bronchofiberscope connected with the jet ventilator into endobronchial tube and inflated the pulmonary segment to be removed. This technique provided the clear identification of the pulmonary segment, but it can cause the barotrauma by hyperinflation and an expansion of an inappropriate other segment. During the inflation of the pulmonary segment, we have to pay close attention to the signs of pulmonary hyperinflation in close cooperation with operators.