Cockcroft-Gault revisited: New de-liver-ance on recommendations for use in cirrhosis

Figure 1 Impact of various body weights used in estimating creatinine clearance from Winter et al[1]. In patients with a BMI ≥ 25 kg/m², using AdjBW0.4 was the most accurate weight to estimate CrCl when compared to a 24-h urine CrCl. Under Wt: BMI < 18.5 kg/m²; Normal Wt: BMI 18.5-24.9 kg/m²; Overweight: BMI 25-29.9 kg/m²; Obese: BMI 30-39.9 kg/m²; Morbidly obese: BMI ≥ 40 kg/m²; CrCl: Creatinine clearance; ActBW: Actual body weight; IBW: Ideal body weight; AdjBW: Adjusted body weight; LBW: Lean body weight; BMI: Body mass index.

Figure 2 Systemic effects of cirrhosis. Increased portal vein pressure results in vasodilation decreasing peripheral vascular resistance (PVR) and effective arterial blood volume (EABV). To compensate for this, increased renin-angiotensin-aldosterone (RAA) activation leads to sodium and fluid retention along with renal vasoconstriction and reduced glomerular filtration rate. Adopted with permission from Ho et al[27]. HE: Hepatic encephalopathy.

Figure 3 In cirrhotics, as renal function declines, conventional methods of estimating renal function are no longer accurate. Both the Cockcroft-Gault (CG) equation and a 24-h urine creatinine clearance (Ccr) significantly overestimated true renal function as measured by inulin clearance (InCl) in cirrhotics with a baseline InCl ≤ 80 mL/min. The CG equation and Ccr were better estimates in those with a baseline InCl > 80 mL/min[33].