Renal replacement therapy in the ICU: the Australian experience

Prolonged Daily Intermittent Renal Replacement Therapy in ICU Patients by ICU Nurses and ICU Physicians

Objectives

Prolonged daily intermittent renal replacement therapy (PDIRRT) has been proposed as a new form of treatment for severe acute renal failure (ARF). However, this treatment has so far implied a) full dependence on nephrological input, b) lack of any convective clearance and c) limited purification of dialysate water. The aim of this study was to establish the feasibility and safety of performing PDIRRT in the ICU with a) no nephrological input, b) the addition of some convective clearance with on-line fluid replacement and c) a new advanced water purification system.

Design

Prospective observational study.

Patients

Fourteen patients treated with PDIRRT.

Setting

ICU of tertiary institution.

Interventions

Treatment of patients with severe ARF and critical illness with PDIRRT. Prescription of treatment by ICU physicians. Conduct of treatment by ICU nurses. Use of combined convective and diffusive therapy with on-line generation of fluid replacement, application of a double-filtration water purification system.

Measurements and Main Results

We prospectively collected demographic, biochemical, hemodynamic and clinical data in 14 patients, who received 30 PDIRRT treatments for a cumulative treatment time of 205.4 hours. The mean age was 57.9 ± 16.0. Eight patients were male and 6 female. Their mean APACHE II score was 24.6 ± 5.9 and their SAPS II score was 41.7 ± 18.8. PDIRRT was used after at least 24 hours of initial stabilization with continuous veno-venous hemofiltration (CVVH). Blood flow was kept at 100ml/min dialysate flow at 200 ml/min and convective clearance varied from 21 ml/min to 33 ml/min. All patients were either anuric or oliguric (UO < 400 ml/day). Ten patients were on mechanical ventilation and 11 patients on vasopressor support. Mean treatment session time was 6.9 ± 1.8 hours. The mean pre-PDIRRT urea was 19.2 ± 6.9 mmol/L and the creatinine was 274 ± 116 μmol/L. The mean pre-PDIRRT lactate was 2.95 ± 2.24 mmol/L. Following treatment, all had significantly decreased to 13.2 ± 6.3 mmol/L, 215 ± 95 μmol/L and 2.25 ± 1.61 mmol/L, respectively (p=<0.0001, <0.0001, <0.05). Bicarbonate levels remained stable during treatment (23.0 ± 3.8 mmol/L to 23.1 ± 2.5 mmol/L). Mean norepinephrine dose changed from 8.8 ± 11.9 μg/min to 12.9 ± 27.0 μg/min after treatment (NS). There were no complications of therapy. Patient ICU survival was 71.4%.

Conclusions

PDIRRT with combined diffusive and convective clearance is an efficacious form of renal replacement, which can be safely and effectively conducted by ICU nurses following prescription by ICU physicians without any nephrological involvement and with adequate double filtration water purification.

Renal replacement therapy in adult and pediatric intensive care : Recommendations by an expert panel from the French Intensive Care Society (SRLF) with the French Society of Anesthesia Intensive Care (SFAR) French Group for Pediatric Intensive Care Emergencies (GFRUP) the French Dialysis Society (SFD)

Acute renal failure (ARF) in critically ill patients is currently very frequent and requires renal replacement therapy (RRT) in many patients. During the last 15 years, several studies have considered important issues regarding the use of RRT in ARF, like the time to initiate the therapy, the dialysis dose, the types of catheter, the choice of technique, and anticoagulation. However, despite an abundant literature, conflicting results do not provide evidence on RRT implementation. We present herein recommendations for the use of RRT in adult and pediatric intensive care developed with the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system by an expert group of French Intensive Care Society (SRLF), with the participation of the French Society of Anesthesia and Intensive Care (SFAR), the French Group for Pediatric Intensive Care and Emergencies (GFRUP), and the French Dialysis Society (SFD). The recommendations cover 4 fields: criteria for RRT initiation, technical aspects (access routes, membranes, anticoagulation, reverse osmosis water), practical aspects (choice of the method, peritoneal dialysis, dialysis dose, adjustments), and safety (procedures and training, dialysis catheter management, extracorporeal circuit set-up). These recommendations have been designed on a practical point of view to provide guidance for intensivists in their daily practice.

Intermittent versus continuous renal replacement therapy: a matter of controversy

BACKGROUND

Acute Renal Failure (ARF) requiring some form of replacement therapy is a frequent complication in the critically ill patient. Despite potential therapeutic advantages the expectation of an improvement in patient outcomes using Continuous Renal Replacement Therapy (CRRT) compared to conventional Intermittent Haemodialysis (IHD) remains controversial.

AIMS AND METHOD

This article will review the literature on the issues surrounding the use of IHD versus CRRT in the management of the critically ill patient. Articles were selected according to level of evidence with priority given to meta-analyses and randomised controlled trials.

DISCUSSION

Several operational features of CRRT allow this technique to be tolerated more easily in critical illness than IHD. The gradual removal of fluid reduces the incidence of hypotension and the risk of volume overload. Decreased variability in the concentration of solutes enables greater azotemia control. However, CRRT is required to operate uninterrupted to achieve a treatment dose that is equivalent to a conventional IHD treatment schedule. In the absence of definitive evidence to validate superior patient survival and return of renal function there is disagreement as to the most appropriate form of Renal Replacement Therapy (RRT) for the critically ill patient. The introduction of 'hybrid' therapies offers a further alternative treatment strategy, which combine favourable aspects of IHD and CRRT.

CONCLUSION

The decision to use IHD or CRRT should be guided by the therapeutic needs of the patient rather than the operational differences between the two techniques. The resources and expertise available at the organisation are also important in determining the mode best able to manage the critically ill patient at any stage and may change according to the severity of illness. The emergence of hybrid therapies provides a compromise option which encompasses many of the features of both systems, but does not embrace all options of either approach.

Enfermería de cuidados críticos y técnicas continuas de reemplazo renal en la Comunidad de Madrid

The continuous renal replacement techniques (CRRT) aim to substitute the altered renal function during a period of time, presenting advantages compared to conventional hemodialysis (CH). This study aims to determine the situation of the CRRT in the Intensive care units (ICU) of the Madrid Community (MC) using a survey distributed to nurses (n = 131) of 14 ICU. It evaluates four aspects of the CRRT: management model, knowledge, problems and degree of satisfaction. It identified four models, the most frequent is that in which ICU nurse and intensivist participate (60%). Self-evaluation of knowledge was fair in 55.7% of the cases and the mean of correct responses in an evaluation of 10 questions was 4.19 and 5.45 in those with previous courses. A total of 84.7% think that CRRT significantly increases the workloads and 62.6% believe that they should be done by the ICU nurses. The main problem is the lack of knowledge to resolve complications during the technique. We conclude that the ICU nursing can handle the CRRT, adapting the nurse/patient ratio; training programs should be established and the role of the teaching nurse defined in critical renal cares.

Continuous haemofiltration in the intensive care unit

Continuous renal replacement therapy (CRRT) was first described in 1977 for the treatment of diuretic-unresponsive fluid overload in the intensive care unit (ICU). Since that time this treatment has undergone a remarkable technical and conceptual evolution. It is now available in most tertiary ICUs around the world and has almost completely replaced intermittent haemodialysis (IHD) in some countries. Specially made machines are now available, and venovenous therapies that use blood pumps have replaced simpler techniques. Although, it remains controversial whether CRRT decreases mortality when compared with IHD, much evidence suggests that it is physiologically superior. The use of CRRT has also spurred renewed interest in the broader concept of blood purification, particularly in septic states. Experimental evidence suggests that this is a promising approach to the management of septic shock in critically ill patients. The evolution and use of CRRT is likely to continue and grow over the next decade.