Continuous arteriovenous hemodiafiltration in postoperative and traumatic renal failure

Continuous arteriovenous hemodialysis and continuous venovenous hemofiltration in burn patients with acute renal failure

Acute renal failure (ARF) is a very common condition that may occur in patients with major burn injuries. The majority of burn patients with ARF have a high mortality rate, ranging from 73% to 100%. There are several ways to treat ARF in burn patients, including peritoneal dialysis (PD), intermittent hemodialysis, and continuous renal replacement therapy (CRRT). CRRT is generally used in patients in whom intermittent hemodialysis has failed to control hypovolemia, as well as in patients who cannot tolerate intermittent hemodialysis. Additionally, PD is not suitable for patients with burns within the abdominal area. For these reasons, most patients with unstable hemodynamic conditions receive CRRT. In this study (conducted in our burn unit between 1997 and 2004), six burn patients received CRRT: three received continuous arteriovenous hemodialysis (CAVHD) and the other three received continuous venovenous hemofiltration (CVVH). The patients were all males, with a mean age of 49.8 years (range, 27-80 years), and a mean burnt surface area of 65.1% (range, 30-95%). Four patients died due to multiple organ failure, and two patients recovered from severe ARF. CRRT has been proven safe and useful for burn patients with ARF. According to this study, we conclude that CVVH is an appropriate tool for treating ARF, with a lower incidence of vascular complications than CAVHD.

Safety of perioperative hemodialysis and continuous hemodiafiltration for dialysis patients with cardiac surgery

OBJECTIVE

We have routinely used postoperative continuous hemodiafiltration (CHDF) combined with intraoperative hemodialysis (IHD) for dialysis patients undergoing open-heart surgery. This perioperative management could avoid any limitation of potassium concentration in the cardioplegic solution, strict restriction of fluid administration, or blood transfusion.

METHODS

To evaluate the safety of this strategy, 22 dialysis patients who underwent open-heart surgery (Dialysis Group) were retrospectively compared with 30 patients with normal renal function selected from the same time period with rigorously matched clinical characteristics such as age, gender, and operative procedures (Matched Group).

RESULTS

No significant difference was found in the operative variables such as the operative procedures, cardiopulmonary bypass time, and aortic cross-clamp time in both groups. There were two deaths (9.1%) in the Dialysis Group compared with Matched Group (0%). In the Dialysis Group, the levels of serum potassium and creatinine were well controlled in the perioperative period with a mean duration of IHD and CHDF of 243.7 +/- 60.6 min and 2.7 +/- 1.1 days, respectively. In particular, no significant difference between intraoperative and postoperative levels of serum potassium was observed in the Dialysis Group (P = 0.09), whereas there was a significant increase in the Matched Group (P = 0.004). Mean volume administered for the first 24 h after surgery was not different from the Matched Group. There were no vascular access-related complications in the Dialysis Group.

CONCLUSIONS

Postoperative CHDF combined with IHD can provide a similar management protocol for dialysis patients compared to patients with normal renal function.

Has mortality from acute renal failure decreased? A systematic review of the literature

PURPOSE

To determine mortality rates in patients with acute renal failure during the past decades.

METHODS

We performed a MEDLINE search using the keywords "acute renal failure" crossed with "outcome," "mortality," "ICU," "critically ill" or "prognosis" in the period from January 1970 to December 2004. Abstracts and full articles were eligible if mortality rates were reported. We also reviewed the bibliographies of available studies for further potentially eligible studies. The dates of the observation period for each study and not the publication dates were considered for the analysis, so the earliest data were from 1956.

RESULTS

Of 85 articles fulfilling the criteria, 5 were excluded because of duplicate publications using the same database, so that 80 were included in our review with a total of 15897 patients. Mortality rates in most studies exceeded 30%, and there was no consistent change over time.

CONCLUSION

Despite technical progress in the management of acute renal failure over the last 50 years, mortality rates seem to have remained unchanged at around 50%.

The Acute Dialysis Quality Initiative--part VI: access and anticoagulation in CRRT

Both the choice of vascular access and anticoagulant regimen for continuous renal replacement therapy (CRRT) are a major determinant of not only circuit life span but also affect solute clearance. This evidence-based review critically examines the published rature on different vascular access sites, access types, and anticoagulation regimens, to provide clinical guidelines for good working practices and to direct future studies.

Upper extremity vascular access for continuous arteriovenous hemofiltration and dialysis after cardiac operations

BACKGROUND

There is increasing interest in the use of continuous arteriovenous hemofiltration/dialysis for treatment of profound renal failure after cardiovascular operations. Vascular access for this is usually accomplished by percutaneous cannulation of the femoral artery and vein, with the inherent risks of vascular trauma, patient immobilization, hemorrhage, or infectious complications.

METHODS

Fifteen (0.36%) of 4,166 patients receiving cardiovascular surgical procedures sustained postoperative renal failure requiring treatment with continuous arteriovenous hemofiltration/dialysis. Each patient had creation of acute arteriovenous forearm access using a modified Allen-Brown shunt. Shunts were monitored continuously for hemorrhage, malfunction, infection, and thrombus, and were explanted when no longer required.

RESULTS

Sixteen shunts were implanted in 15 patients over the 41-month period. All shunts functioned satisfactorily, with the duration of implantation ranging from 1 to 64 days. There were no infectious or hemorrhagic complications.

CONCLUSIONS

The acute creation of a simple forearm shunt for postoperative continuous arteriovenous hemo-filtration/dialysis is preferred over femoral arterial and venous cannulation because it can be constructed rapidly and easily in the operating room or at the bedside, has a low complication rate, is available for immediate use, may be left in place indefinitely, does not interfere with patient mobilization or ambulation, and is easily removed.