Non-renal indications for continuous renal replacement therapy

Congestive heart failure in patients with chronic kidney disease and on dialysis

CHF is highly prevalent in ESRD and is a leading cause of death in such patients. Hypertension, renal anemia, and comorbid conditions such as coronary artery disease are particularly important risk factors for CHF in ESRD. Dialysis hypotension may be a marker of poor prognosis in such persons. Recent studies suggest that lipid peroxidation and L-carnitine deficiency may contribute to CHF in some patients with ESRD. All forms of renal replacement therapy are capable of ameliorating symptoms of CHF, but their effect on cardiovascular mortality has not been firmly established. Drug therapy, particularly angiotensin-converting enzyme inhibitors and beta-adrenergic receptor blockers, is under-used in patients with ESRD and CHF. Heart/kidney transplantation may be a viable option for some patients with advanced CHF and ESRD.

Incidence, risk factors, and prognosis of a moderate increase in plasma creatinine early after cardiac surgery

OBJECTIVE

To evaluate the incidence and prognosis of a moderate increase in serum creatinine early after cardiac surgery.

DESIGN

Retrospective clinical study.

SETTING

Surgical intensive care unit in a university hospital.

PATIENTS

Five hundred and ninety-one consecutive adult patients operated on for cardiac surgery during 1 year.

INTERVENTIONS

Plasma creatinine was measured systematically before and during the first 3 days after surgery. Comorbid events were assessed as organ dysfunction (cardiac, pulmonary, hematologic, and neurologic), allowing us to calculate for each patient a dysfunction score (0-5).

MEASUREMENTS AND MAIN RESULTS

Postoperative plasma creatinine increased by > or =20% in 15.6% of patients; eight of these required dialysis. A 20% increase in plasma creatinine was associated with other organ dysfunction in 79.3% of patients. Overall mortality rate was 2.7% and increased with the dysfunction score (17.7% for a dysfunction score > or =3). Mortality rate was 12.0% for patients who had 20% increased plasma creatinine with other organ dysfunction but was 0% for patients without other organ dysfunction. A logistic regression analysis revealed that the most important prognostic factors of death were cardiac dysfunction (odds ratio, 8.5; 95% confidence interval, 2.2-32.5) and the association of renal dysfunction and hematologic dysfunction (odds ratio = 12.0; 95% confidence interval, 3.9-37.2). Mean intensive care unit stay of patients with increased plasma creatinine was significantly longer (8.1 +/- 5.6 vs. 4.3 +/- 1.4 days, p <.01) and increased significantly with the dysfunction score (p <.01). Patients with isolated increased plasma creatinine had a significantly longer stay in the intensive care unit than patients without any organ dysfunction (4.6 +/- 1.4 vs. 3.9 +/- 0.9, p <.01).

CONCLUSION

Our results suggest that a postoperative 20% increase in plasma creatinine after cardiac surgery is not rare and has a significant impact on postoperative outcome, mainly when multiple organ dysfunction occurs. Any preoperative reduced renal reserve or perioperative renal ischemia increases the renal risk.

The dialytic management of acute renal failure in the elderly

In this article the different dialysis strategies in the management of acute renal failure (ARF) in the elderly are discussed. Although peritoneal dialysis (PD) offers some theoretical advantages, there are several medical and technical reasons why it is currently less frequently used. The choice between intermittent hemodialysis (HD) and continuous renal replacement therapy (CRRT) is determined by a number of considerations, the most important ones being hemodynamic stability, the need for hyperalimentation and/or ultrafiltration, and the local experience with one or both techniques. Some recent studies with CRRT in elderly ARF patients describe favorable results. Slow extended daily dialysis (SLEDD) modalities may be particularly indicated in elderly, critically ill ARF patients because these techniques combine the advantages of both CRRT and HD. Finally, the importance of the biocompatibility of dialysis membranes is discussed. Although there are a number of theoretical arguments to use biocompatible membranes, this opinion is not always supported by the results of recent comparative studies. It is the opinion of the authors that all dialysis strategies should be mastered and utilized for appropriate indications in elderly ARF patients.

Failure of continuous venovenous hemofiltration to prevent death in paraquat poisoning

Paraquat poisoning is characterized by multiorgan failure and pulmonary fibrosis with respiratory failure. Multiorgan failure with circulatory collapse is a major cause of early death within 3 days of paraquat ingestion. Recent studies suggested that continuous venovenous hemofiltration (CVVH) had a role in the treatment of multiorgan failure by promoting hemodynamic stability. We therefore evaluated the effect of prophylactic CVVH in 80 patients with paraquat poisoning (August 1996 to February 1999). The amount ingested was 2.1 +/- 1.0 mouthfuls (as 20% concentrate). All patients were treated with hemoperfusion (HP; duration, 6.4 +/- 3.0 hours) within 24 hours of ingestion and then randomly assigned to the HP-alone or HP-CVVH group. Forty-four patients underwent HP only, and 36 patients underwent CVVH (duration, 57.4 +/- 31.3 hours; ultrafiltration volume, 40.2 +/- 4.8 L/d) after HP. Although time to death after ingestion was significantly longer in the HP-CVVH than HP group (5.0 +/- 5.0 versus 2.5 +/- 2.1 days; P < 0.05), there was no difference in mortality rates between the two groups (66.7% versus 63.6%; P = 0.82). In the HP group, early circulatory collapse was a major cause of death compared with the HP-CVVH group, in which late respiratory failure was a major cause of death. In conclusion, prophylactic CVVH after HP prevented early death caused by circulatory collapse and prolonged survival time. However, it could not prevent late death caused by respiratory failure and did not provide a survival benefit in acute paraquat poisoning.

Improved outcome prediction for patients with multiple organ failure undergoing continuous hemodiafiltration

A number of patients with multiple organ failure (MOF) regardless of accompanying acute renal failure have been treated with continuous hemodiafiltration (CHDF). However, despite its high cost, the costs/benefits of CHDF for MOF patients still need to be evaluated. Although many scoring systems were established to predict the outcome of MOF, their predictive powers were not estimated in MOF patients undergoing CHDF. Therefore, using 52 Japanese patients with MOF treated with CHDF for more than 1 week, we estimated the predictive powers of multiple organ dysfunction (MOD) scores and acute physiology and chronic health evaluation (APACHE) III scores, retrospectively. The patients were divided into 2 groups according to outcome at Day 28 after the initiation of CHDF. In both scoring systems, the median values at Day 0 were not significantly different between the survival (n = 19) and the nonsurvival (n = 33) groups. In contrast, at Day 3, the median values of MOD scores was 4 (0-14) in the survival group and 9 (1-12) in the nonsurvival group (p = 0.0035). The median value of APACHE III scores were 37 (19-97) and 87 (16-150) at Day 3, respectively (p < 0.0001). In the survival group, APACHE III scores significantly decreased from the median value of 64 (32-89) to 37 (p = 0.0269), and in the nonsurvival group, it increased significantly from the median value of 70 (29-103) to 87 (p = 0.0116). In contrast, no significant changes were observed in the MOD scores. In conclusion, the MOD score and the APACHE III score systems had less power to predict the outcome of MOF patients undergoing CHDF at Day 0. However, rescoring at Day 3 of each index was much more powerful to accurately predict the outcome of such patients.