[Behaviour of vancomycin with the new techniques in haemodialysis]

When using high convection dialysis techniques it arouses the necessity of considering the suitability of the regular protocols when administrating drugs, such as vancomycin.

To confirm if the usual guideline of vancomycin is efficient in patients undergoing treatments with acetate free biofiltration (AFB) and haemodiafiltration on-line (on-line). To propose an alternative guideline of administration.

13 patients treated with AFB or On-line. 10 of them used filters of polysulfone and 3 of them of AN69. First part: 6 patients were administered 1 g iv during the last hour of dialysis. Second part: 7 patients were given a loading dose of 30 mg/kg iv with a reinforcement of 500 mg post-dialysis. The blood levels of the antibiotic were monitorized during the week following the administration.

During the first phase it was noticed a decrease of 41% in the serum level of vancomycin during dialysis, conditioning subtherapeutic levels in the 83% of the patients until the end of the study. As for the second phase, therapeutic non-toxic levels were maintained during the whole study. The existence of a post-dialysis rebound of the 21 % was confirmed. A bigger clearance of vancomycin was obtained with the On-line technique rather than with AFB (176 vs 135 ml/min). We find a strong correlation between the decrease of the antibiotic and the volume ultrafiltrated with the On-line technique.

The usual guideline of vancomycin may not be enough with the new convective dialysis techniques. A guideline based on a loading dose of 30 mg/kg and a reinforcement of 500 mg at the end of each dialysis could be adequate. The antibiotic clearance with the On-line technique is probably made by convective transport.