Continuous renal replacement therapy versus furosemide for management of kidney impairment in heart transplant recipients with volume overload

The purpose of this retrospective cohort study was to examine the associations among chronic kidney disease, anemia, and risk of death among patients with heart failure. Retrospective cohort study. Patients with a principal diagnosis of heart failure (ICD9 codes 402.01, 402.11, 402.91, 404.01, 404.11, 404.91, and 428.xx) were included. Chronic kidney disease (CKD) was defined as a serum creatinine >1.4 mg/dl for women and >1.5 mg/dl for men. There were 665 eligible patients in the sample with a mean (SD) age of 75.7 (10.9) yr; 60% were women, 71% were white, and 38% had CKD. On admission, a hematocrit > or =40% was found for 30.3% of the patients; 22.9% had a hematocrit between 36% and 40%, 33.2% between 30% and 35%, and 13.6% had a hematocrit of or =40%; 33.8% (RR, 1.08; 95% CI. 0.79 to 1.47) for hematocrit 36 to 39%; 36.7% (RR, 1.17; 95% CI, 0.89 to 1.54) for hematocrit between 30 and 35%; and 50.0% (RR, 1.60; 95% CI, 1.19 to 2.16) for those with a hematocrit <30% (chi(2) for trend was 7.37; P = 0.007). Both hematocrit and serum creatinine were independently associated with increased risk of death during follow-up after controlling for other patient risk factors. In conclusion, CKD and anemia are frequent among older patients with heart failure and are independent predictors of subsequent risk of death.

Patients with critical illness commonly develop acute renal failure requiring mechanical support in the form of either continuous renal replacement therapy (CRRT) or intermittent hemodialysis (IRRT). As controversy exists regarding which modality should be used for most patients with critically illness, we sought to determine whether CRRT or IRRT is associated with better survival. We performed a meta-analysis of all prior randomized and observational studies that compared CRRT with IRRT. Studies were identified through a MEDLINE search, the authors' files, bibliographies of review articles, abstracts and proceedings of scientific meetings. Studies were assessed for baseline characteristics, intervention, outcome and overall quality through blinded review. The primary end-point was hospital mortality, assessed by cumulative relative risk (RR). We identified 13 studies ( n=1400), only three of which were randomized. Overall there was no difference in mortality (RR 0.93 (0.79-1.09), p=0.29). However, study quality was poor and only six studies compared groups of equal severity of illness at baseline (time of enrollment). Adjusting for study quality and severity of illness, mortality was lower in patients treated with CRRT (RR 0.72 (0.60-0.87), p<0.01). In the six studies with similar baseline severity, unadjusted mortality was also lower with CRRT (RR 0.48 (0.34 -0.69), p<0.0005). Current evidence is insufficient to draw strong conclusions regarding the mode of replacement therapy for acute renal failure in the critically ill. However, the life-saving potential with CRRT suggested in our secondary analyses warrants further investigation by a large, randomized trial.

Based on the data derived from the Modification of Diet in Renal Disease (MDRD) study, a new equation was developed for the estimation of glomerular filtration rate (GFR). This equation, which takes into account body weight, age, sex, serum creatinine, race, serum urea, and serum albumin, provided a more accurate estimation of GFR in patients with renal insufficiency. However, this prediction equation has not been validated in subjects with normal or supra-normal GFR. In a cross-sectional study, we measured GFR by inulin clearance in 46 healthy controls and 46 non-complicated type 1 diabetic patients. In this study population, GFR was predicted by measured creatinine clearance, the Cockcroft-Gault formula, and the MDRD equation. In the healthy subjects, mean GFR (+/-SD) was 107+/-11 as compared to 122+/-18 ml/min per 1.73 m(2) in the diabetic patients. This difference in GFR was reflected by a lower serum creatinine (76+/-8 vs 71+/-8 micro mol/l) in the diabetic patients. In the healthy controls, median absolute differences (and the 50th-75th-90th percentile of percentage absolute differences) between predicted and measured GFR were 5.2 ml/min per 1.73 m(2) (4.9-9.8-18.5%) for creatinine clearance, 9.0 ml/min per 1.73 m(2) (8.6-14.3-24.6%) for the Cockcroft-Gault formula, and 10.7 ml/min per 1.73 m(2) (10.9-16.3-25.5%) for the MDRD equation. In the diabetic patients, these differences were 8.3 ml/min per 1.73 m(2) (7.6-9.3-13.0%) for creatinine clearance; 11.8 ml/min per 1.73 m(2) (10.1-16.0-22.5%) for the Cockcroft-Gault formula, and 18.8 ml/min per 1.73 m(2) (16.0-24.2-31.9%) for the MDRD equation. In subjects with a normal or increased GFR, the new MDRD-prediction equation of GFR is less accurate than creatinine clearance or the Cockcroft-Gault formula, and offers no advantage.