Evaluation of Vancomycin and Gentamicin Dialysis Clearance Using In Vivo and In Vitro Systems

Figures & data

Table 1.  In vitro conditions and solute clearances for IHD and SLED.

Conditions	IHD	SLED
Dialyzer	F180	F50
QR (mL/min)	200	150
QD (mL/min)	500	350
CLD (mL/min)
Vancomycin	131 ± 2	72 ± 9
Gentamicin	154 ± 2	84 ± 11
Urea	195 ± 2	129 ± 17
Creatinine	187 ± 3	120 ± 14

Notes: CL_D, dialysis clearance reported as mean ± SD (mL/min); IHD, intermittent hemodialysis; Q_D, dialysate flow rate (mL/min); Q_R, reservoir flow rate (mL/min); SLED, sustained low-efficiency dialysis; F180, surface area 1.8 m², K_uf 60 mL/h/mmHg; F50, surface area 1.0 m², K_uf 29 mL/h/mmHg.

Table 2.  Patient characteristics and dialysis conditions for vancomycin in vivo study.

Subject number	Age (years)	Gender	Weight (kg)	HD access	Hct level (%)	Qb (mL/min)	Qp (mL/min)	QD (mL/min)	UFR (mL/min)	CLD (mL/min)
1	21	M	67	Fistula	34.5	350	229	600	17	99
2	39	M	93	Graft	27.1	400	292	600	17	136
3	34	F	99	Vascath	30.1	350	245	600	6	95
4	62	M	88	Graft	33.8	400	265	600	14	114
5	48	F	79	Fistula	34.6	300	196	600	6	103
6	58	M	70	Graft	36.4	400	254	600	35	108
7	66	F	97	Fistula	30.4	400	278	600	12	103
8	30	F	91	Fistula	39.8	350	211	700	22	79
9	60	F	60	Vascath	29.7	270	190	600	16	87
10	53	M	72	Permacath	29.8	350	246	700	20	106
Mean ± SD	47 ± 15	–	82 ± 14	–	32.6 ± 3.8	357 ± 45	240 ± 34	620 ± 42	17 ± 8	103 ± 15

Notes: CL_D, dialysis clearance; F, female; Hct, hematocrit; HD, hemodialysis; M, male; Q_b, blood flow rate; Q_D, dialysate flow rate; Q_p, plasma flow rate; UFR, ultrafiltration rate.

Table 3.  Patient characteristics and dialysis data for gentamicin in vivo study.

Subject number	Age (years)	Gender	Weight (kg)	HD access	Hct level (%)	Qb (mL/min)	Qp (mL/min)	QD (mL/min)	UFR (mL/min)	CLD (mL/min)
1	58	M	76	Graft	33.8	400	265	600	12	172
2	55	F	83	Fistula	25.2	300	224	500	12	141
3	30	F	91	Fistula	39.8	350	211	700	22	124
4	60	F	60	Vascath	29.7	270	190	600	16	86
5	53	M	72	Permacath	29.8	350	246	700	20	140
6	52	F	139	Permacath	32.7	400	269	500	22	128
7	53	M	89	Vascath	39.3	280	170	600	17	133
Mean ± SD	52 ± 10	–	87 ± 25	–	32.9 ± 5.3	336 ± 54	225 ± 37	600 ± 82	17 ± 4	132 ± 25

Notes: CL_D, dialysis clearance; F, female; Hct, hematocrit; HD, hemodialysis; M, male; Q_b, blood flow rate; Q_D, dialysate flow rate; Q_p, plasma flow rate; UFR, ultrafiltration rate.

Table 4.  In vivo SLED data previously reported.

Study	Vancomycin^12	Gentamicin^13
Number of subjects	10	8
Dialyzer	F60^a	F50^b
Qb (mL/min)	160	200
QD (mL/min)	160	300
CLD (mL/min)	63	76

Notes: CL_D, dialysis clearance reported as mean ± SD (mL/min); Q_b, blood flow rate; Q_D, dialysate flow rate; SLED, sustained low-efficiency dialysis.

^aF60, Fresenius polysulfone dialyzer; surface area 1.3 m², K_uf = 38 mL/h/mmHg.

^bF50, surface area 1.0 m², K_uf 29 mL/h/mmHg.