Use Of Continuous Venovenous Hemodialysis Research Articles

CVVHD treatment with CARPEDIEM: small solute clearance at different blood and dialysate flows with three different surface area filter configurations.

The CARdiorenal PEDIatric EMergency (CARPEDIEM) machine was originally designed to perform only continuous venovenous hemofiltration (CVVH) in neonatal and pediatric patients. In some cases, adequate convective clearance may not be reached because of a limited blood flow. In such conditions, the application of diffusive clearance [continuous venovenous hemodialysis (CVVHD)] would help optimize blood purification. In this study, the CARPEDIEM™ machine was modified to enable the circulation of dialysis through the filter allowing testing of the performance of CARPEDIEM™ machine in CVVHD. Three different polyethersulfone hemodialyzers (surface area = 0.1m(2), 0.2m(2), and 0.35m(2), respectively) were tested in vitro with a scheduled combination of plasma flow rates (Qp = 10-20-30ml/min) and dialysis fluid flow rate (Qd = 5-10-15ml/min). Three sessions were performed in co-current and one in counter-current configuration (as control) for each filter size. Clearance was measured from the blood and dialysate sides and results with mass balance error greater than 5% were discarded. Urea and creatinine clearances for each plasma/dialysate combination are reported: clearance increase progressively for every filter proportionally to plasma flow rates. Similarly, clearances increase progressively with dialysate flow rates at a given plasma flow. The clearance curve tends to present a steep increase for small increases in plasma flow in the range below 10ml/min, while the curve tends to plateau for values averaging 30ml/min. As expected, the plateau is reached earlier with the smaller filter showing the effect of membrane surface-area limitation. At every plasma flow, the effect of dialysate flow increase is evident and well defined, showing that saturation of effluent was not achieved completely in any of the experimental conditions explored. No differences (p > 0.05 for all values) were obtained in experiments using whole blood instead of plasma or using co-current versus counter-current dialysate flow configuration. Although plasma flow and filter surface give an important contribution to the level of clearance urea and creatinine, it appears evident that dialysate flow plays an essential role in the blood purification process, justifying the use of CVVHD versus CVVH in case of high dialysis dose requirement and/or limited blood flow rate.

Enhanced elimination of dabigatran: Identifying the appropriate patient for the use of continuous venovenous hemodialysis instead of intermittent hemodialysis-A simulation analysis.

There are clinical situations where rapid elimination of dabigatran is beneficial. Intermittent hemodialysis (IHD) removes dabigatran effectively but is not always available and requires a hemodynamically stable patient. We therefore investigated the continuous venovenous hemodialysis (CVVHD) technique for its potency in the elimination of dabigatran. Based on pharmacometric characterization of dabigatran in IHD, we simulated a broad range of dialysis settings for CVVHD and then applied the model to specific clinical situations. Dialysis of 3 hours' duration with typical clinical settings (dialysate flow rate 50 mL/min; blood flow rate 150 mL/min) reduced dabigatran plasma concentration by 14-17% in addition to the patient body clearance. Extending dialysis duration to 8 or 16 hours for patients with severe renal dysfunction resulted in additional reductions from 26% up to 40%. When comparing with IHD for different endpoints (reaching 50% of initial dabigatran concentration, or nondetectability of dabigatran by the Hemoclot test), CVVHD did not reach comparable elimination rates. CVVHD is not fast enough to prepare for urgent interventions in patients with high bleeding risks. However, in situations where less hemodynamically stressful modalities seem indicated, CVVHD might be useful in moderately to severely renally impaired patients to accelerate dabigatran elimination.

Venovenous Extracorporeal Membrane Oxygenation for Postoperative Acute Respiratory Distress Syndrome.

BackgroundExtracorporeal membrane oxygenation (ECMO) has recently attracted interest as a treatment for severe acute respiratory distress syndrome (ARDS). However, the outcomes of this procedure in post-surgical settings have not yet been characterized. In this study, we evaluated the outcomes of ECMO in patients with severe postoperative ARDS.MethodsFrom January 2007 to December 2012, a total of 69 patients (aged 58.3±11.5 years, 23 females) who underwent venovenous ECMO to treat severe postoperative ARDS were reviewed. Of these patients, 22 (31.9%) had undergone cardiothoracic surgery, 32 (46.4%) had undergone liver transplantation, and 15 (21.7%) had undergone other procedures.ResultsThirty-four patients (49.3%) were successfully weaned from ECMO, while the other 35 patients (50.7%) died on ECMO support. Among the 34 patients who were successfully weaned from ECMO, 21 patients (30.4%) eventually died before discharge from the hospital, resulting in 13 hospital survivors (18.8%). Multivariable analysis showed that the duration of pre-ECMO ventilation was a significant independent predictor of death (odds ratio [OR], 2.25; 95% confidence interval [CI], 1.29 to 3.90; p=0.004), whereas the concomitant use of continuous venovenous hemodialysis (CVVHD) was associated with improved survival (OR, 0.55; 95% CI, 0.31 to 0.97; p=0.038).ConclusionAlthough the overall survival rate of patients treated with ECMO for postoperative ARDS was unfavorable, ECMO offered an invaluable opportunity for survival to patients who would not have been expected to survive using conventional therapy. CVVHD may be beneficial in improving the outcomes of such patients, whereas a prolonged duration of pre-ECMO ventilator support was associated with poor survival.

Alcohol-Induced Coma, Hypothermia and Hypotension

Objectives: Coma, hypothermia and hypotension caused by alcohol and benzodiazepine intoxication can be successfully treated with the use of continuous veno-venous hemodialysis (CVVHD). It eliminates small molecules, corrects pathological laboratory parameters and gradually heats the blood. Methods: We present a case report of a female patient suffering from depression who attempted suicide with benzodiazepine, karbamazepine and alcohol ingestion. She was brought into the intensive care unit in a comatous state (GCS score–3), with an arterial blood pressure of approximately 40 mmHg, body temperature less than 30°C, blood alcohol concentration of 550 mg/dL, and positive assessments for benzodiazepines and karbamazepine. The nefrologist indicates that CVVHD is necessary. Results: Alcohol blood levels fell to 170 mg/dL after 10 hours of CVVHD, while blood pressure and body temperature rose. After CVVHD, alcohol blood levels dropped to 0.002 mg/dL, body temperature measured 35.5°C, and blood pressure, diuresis and electrolite status were of normal levels. Conclusion: CVVHD (along with measures of intensive treatment) had a positive outcome on a patient that was vitally endangered by suicide attempt. This is based on the fact that CVVHD gives adequate clearance of alcohol and benzodiazepines, corrects electrolite status, and gradually raises body temperature by extracorporal circulation.

Successful treatment of severe carbamazepine toxicity with 5 % albumin-enhanced continuous venovenous hemodialysis

Carbamazepine overdose is a common, toxic ingestion, manifesting as central nervous system (CNS) and respiratory depression. Carbamazepine is highly protein bound with a large volume of distribution and, therefore, inefficiently removed by conventional hemodialysis. We describe the successful use of continuous venovenous hemodialysis (CVVHD) with 5% albumin enhanced dialysate in a 31-year-old female who developed CNS depression, hypotension and respiratory failure, requiring mechanical ventilation, after an intentional ingestion of approximately 10 g of extended release carbamazepine, Tegretol CR(®). The peak drug level was 26 mcg/ml, therapeutic range 8-12 mcg/ml, with toxicity often developing a level above 15 mcg/ml. Normal half-life of drug elimination is 35-60 h in carbamazepine naïve patients. In contrast, with albumin-enhanced dialysis, we observed a drug half-life of 18 h. She was extubated on day two and was transferred to inpatient psychiatry by day 3 without significant neurologic sequelae. In vitro studies have been done with bovine blood demonstrating significant carbamazepine removal using CVVHD with albumin-enhanced dialysate. There has been very limited experience using albumin-enhanced CVVHD in an adult patient with carbamazepine toxicity.

Impact of Computerized Order Entry and Pre-mixed Dialysis Solutions for Continuous Veno-Venous Hemodiafiltration on Selection of Therapy for Acute Renal Failure

To investigate the impacts of availability of pre-mixed solutions and computerized order entry on nephrologists' choice of the initial mode of renal replacement therapy in acute renal failure. We studied 898 patients with acute renal failure in 3 consecutive eras: era 1 (custom-mixed solution; n = 309), era 2 (pre-mixed commercial solution; n = 324), and era 3 (post-computerized order entry; n = 265). The proportion of patients treated with renal replacement therapy and the time from consult to initiation of continuous renal replacement therapy was similar in the 3 eras. Following introduction of the pre-mixed solution, the proportion of patients treated with continuous renal replacement therapy increased (20% vs. 33%; p < 0.05), it was initiated at a lower serum creatinine (353 ± 123 μmol/L vs. 300 ± 80 μmol/L; p < 0.05) and in older patients (53 ± 12 vs. 61 ± 14 years; p < 0.05). There was a progressive increase in the use of continuous veno-venous hemodialysis (18% vs. 79% vs. 100%; p < 0.05) and in the total prescribed flow rate (1,382 ± 546 vs. 2,324 ± 737 vs. 2,900 ± 305 mL/hr 3; p < 0.05). There was no significant impact on mortality. The availability of a pre-mixed solution increases the likelihood of initiating continuous renal replacement therapy in acute renal failure, initiating it at a lower creatinine and for older patients, use of continuous veno-venous hemodialysis and higher prescribed continuous renal replacement therapy dose. Computerized order entry implementation is associated with an additional increase in the use of continuous veno-venous hemodialysis, higher total prescribed dialysis dose, and use of CRRT among an increasing number of patients not on mechanical ventilation. The effect of these changes on patient survival is not significant.

58: Use of Continuous Venovenous Hemodialysis (CVVHD) to Reverse Persistent Anion Gap and Non-Anion Gap Metabolic Acidosis From Pine-Sol® Poisoning

58: Use of Continuous Venovenous Hemodialysis (CVVHD) to Reverse Persistent Anion Gap and Non-Anion Gap Metabolic Acidosis From Pine-Sol® Poisoning

Organ recovery from a donor with end-stage renal disease: a case study

As the field of transplantation enters the new millennium, maximizing organs per donor remains one of the greatest challenges of procurement. This case study outlines nontraditional medical management techniques that facilitated the recovery of 5 transplantable organs from a patient with end-stage renal disease. Strategies utilized in this case included the use of continuous veno-venous hemodialysis and airway pressure release ventilation to maximize the outcomes of the donation. Although the use of these strategies is admittedly limited to hospitals where the resources are available, this case study suggests that utilizing available resources in any clinical setting can make more organs available to people on the waiting list for solid organ transplantation.

Renal replacement therapy and orthotopic liver transplantation: the role of continuous veno-venous hemodialysis.

The need for renal replacement therapy (RRT) either before or after orthotopic liver transplant (OLTX) has been reported to be a poor prognostic indicator for survival. Use of continuous veno-venous hemodialysis (CVVHD) for RRT has been reported in three series of OLTX patients with high 90-day mortality rates of 57-60%. We have examined our patient population to determine the effect of necessity and type of RRT on patient survival after OLTX. We analyzed 1535 OLTX that were performed at our institution from 1985 through 1999, 1037 from 1985 to 1995 (period I) and 498 from 1996 to 1999 (period II). Combined liver-kidney transplants were excluded from analysis. Hospital dialysis unit records and a prospectively maintained database on all OLTX patients served as the source of data. Patients were classified into groups defined on whether or not they received RRT, when they received RRT, and the type of RRT. Groups were compared for preoperative intensive care unit status, time on the waiting list, laboratory variables, 90-day postoperative mortality, 1-year patient survival, and absolute survival. Use of RRT increased from 8.29% in period I to 12.45% in period II, along with increased median waiting times. In period I, patients receiving preoperative RRT had a 90-day mortality (0%) and a 1-year survival (89.5%) almost identical to those patients who never required RRT (1.7% and 90.6%). Patients who developed acute renal failure postoperatively requiring RRT, however, had a 90-day mortality of 28.6% and a 1-year survival of 55%. In period II, patients requiring RRT had a 90-day mortality of 39.7% and a 1-year actuarial survival of 54.5% compared with 6.9% and 88.6% in patients never requiring RRT. Patients treated with CVVHD had a 90-day mortality of 42% compared with 25% in patients treated with hemodialysis alone. However, patients receiving CVVHD both pre- and postoperatively had a 90-day mortality of 27.7% vs. 50% in those patients who only received CVVHD postoperatively. Patients who developed acute renal failure postoperatively, which required RRT, regardless of therapy, had a 1-year survival of only 41.0% compared with a 1-year survival of 73.6% in those patients started on RRT preoperatively, P=0.03. The need for RRT has increased along with waiting time in OLTX patients. Patients developing the need for RRT postoperatively have an increased 90-day mortality and lower 1-year survival with the highest being present in patients receiving CVVHD, which was started postoperatively. These findings may reflect a trend toward a sicker population awaiting OLTX and emphasize the negative impact of renal failure on survival after OLTX.

Continuous venovenous hemodialysis

Hemodialysis and peritoneal dialysis are the main renal replacement therapies for patients with acute renal failure. These patients are often unable to tolerate drastic fluid shifts and other complications of conventional dialysis. Continuous hemodialysis, however, provides protection from the hemodynamic consequences and osmotic stressors of conventional dialysis and is rapidly becoming the treatment of choice for critically ill patients. We present a case in which a patient with a spontaneous cerebellar hemorrhage developed acute renal failure. Surgical evacuation was not an option. Clinical management included the use of continuous venovenous hemodialysis, which is described in the setting of a patient with a posterior fossa mass. The risks of anticoagulation, hemodynamic instability, and development of dialysis disequilibrium syndrome are discussed.