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Timothy E Bunchman

Publications and source records attributed to Timothy E Bunchman.

17 recordsLinked to original sources
PubMed2006

Medication errors and patient complications with continuous renal replacement therapy.

Continuous renal replacement therapy (CRRT) is commonly used for renal support in the intensive care unit. While the risk of medication errors in the intensive care unit has been described, errors related specifically to CRRT are unknown. The purpose of this study is to characterize medication errors related to CRRT and compare medication errors that occur with manually compounded solutions versus commercially available solutions. We surveyed three separate internet-based, pediatric list serves that are commonly used for communications for programs utilizing CRRT. Data regarding CRRT practices and medication errors were recorded. Medication errors were graded for degree of severity and compared between programs using manually compounded dialysis solutions versus commercially available dialysis solutions. In a survey with 31 program responses, 18 reported medication errors. Two of the 18 were related to heparin compounding, while 16/18 were due to solution compounding errors. Half of the medication errors were classified as causing harm, two of which were fatal. All medication errors were reported by programs that manually compounded their dialysis solutions. Medication errors related to CRRT are associated with a high degree of severity, including death. Industry-based, commercially available solutions can decrease the occurrence of medication errors due to CRRT.

Child↗
PubMed2006

Renal replacement therapy in the treatment of confirmed or suspected inborn errors of metabolism.

OBJECTIVE: Analysis of mortality and risk factors for mortality in the use of renal replacement therapy to correct metabolic disturbances associated with confirmed or suspected inborn errors of metabolism. STUDY DESIGN: A retrospective review of an institutional review board-approved pediatric acute renal failure data base at the University of Michigan. Eighteen patients underwent 21 renal replacement therapy treatments for metabolic disturbances caused by urea cycle defects (n = 14), organic acidemias (n = 5), idiopathic hyperammonemia (n = 1), and Reye syndrome (n = 1). RESULTS: There were 14 boys (74%) and 4 girls (26%), with a mean age and weight of 56.2 +/- 71.0 months and 18.5 +/- 19.2 kg, respectively, at the initiation of renal replacement therapy. Overall treatment mortality rate was 57.2% (12 of 21 treatments), with 11 of the 18 patients (61.1%) dying before hospital discharge. Two-year follow-up on those patients demonstrated that 5 patients (71.4%) remained alive. Initial therapy with hemodialysis was associated with improved survival. Ten treatments (47.6%) required transition to another form of renal replacement therapy to maintain ongoing metabolic control, with a mean duration of 6.1 +/- 9.8 days. Time to renal replacement therapy >24 hours was associated with an increased risk of mortality, whereas a blood pressure >5th percentile for age at the initiation of therapy and the use of anticoagulation were associated with a decreased risk of mortality. CONCLUSIONS: Renal replacement therapy can correct the metabolic disturbances that accompany suspected or confirmed inborn errors of metabolism. Our experience demonstrates an approximately 60% mortality rate associated with renal replacement treatment, with more than 70% of survivors living longer than 2 years.

Acidosis↗
PubMed2005

Zero balance ultrafiltration (Z-BUF) in blood-primed CRRT circuits achieves electrolyte and acid-base homeostasis prior to patient connection.

Infants requiring CRRT present a unique challenge due to the large circuit volume to blood volume ratio. Blood priming is often used, but some patients can become unstable during the initiation of CRRT due to electrolyte and acid-base imbalance. We postulated that using Z-BUF we could normalize electrolytes and improve the acid base status of the prime prior to patient connection. To test this we set up a circuit using the Baxter BM-25 CRRT pump, a polysulfone or AN-69 membrane, and a three-way stopcock. The circuit was primed with a 60/40 mix of expired autologous donor pRBCs and 5% albumin. The modalities of CVVH, CVVHD, and CVVHDF were compared for relative efficacy. Electrolytes, lactate, pH, cytokines (TNF-alpha, IL-1beta, bradykinin, and IL-6) were measured. Plasma hemoglobin levels were also measured before and after the Z-BUF procedure. Bradykinin production and elimination in AN-69 membrane circuits were assessed. All lab values equilibrated by 35 minutes. All CRRT modalities were equally efficacious for Z-BUF. Cytokine production or significant hemolysis was not found. In addition, no bradykinin accumulation occurred in AN-69 membrane-containing circuits. We conclude that Z-BUF is a simple and effective way to normalize electrolyte and acid-base status in the CRRT circuit when blood priming is required.

Acid-Base Equilibrium↗
PubMed2005

Multi-centre evaluation of anticoagulation in patients receiving continuous renal replacement therapy (CRRT).

BACKGROUND: Heparin (hepACG) and regional citrate anticoagulation (citACG) remain the most commonly reported continuous renal replacement therapy (CRRT) ACG methods employed. No prospective multi-centre published data exist that compare different ACG methods with respect to CRRT filter life span or patient complications. METHODS: A total of 138 patients from seven US centres receiving 18 208 h of CRRT comprising a total of 442 CRRT circuits were utilized to assess filter life span and ACG-related complications in patients receiving CRRT with hepACG, citACG or no ACG (noACG). RESULTS: Mean circuit life was 41.2+/-30.8 h. Mean circuit survival was no different for circuits receiving hepACG (42.1+/-27.1 h) and citACG (44.7+/-35.9 h), but was significantly lower for circuits with noACG (27.2+/-21.5 h, P<0.005). Kaplan-Meier analyses revealed no survival difference between hepACG and citACG circuits, but significantly lower survival for noACG circuits (P<0.001). Log-rank analysis showed that 69% of hepACG and citACG circuits whereas only 28% of noACG were functional at 60 h. Clotting rates were similar for hepACG circuits (58 out of 230, 25%) and citACG circuits (43 out of 158, 27%), but were significantly higher for noACG circuits (27 out of 54, 50%, P < 0.001). Life-threatening bleeding complications attributable to ACG were noted in the hepACG group but were absent in the citACG group. CONCLUSIONS: The current analysis represents the largest evaluation of CRRT ACG methods to date. While the standard hepACG and citACG methods studied in the prospective paediatric CRRT registry led to similar filter life spans and were superior to noACG, our data suggest that citACG may result in less life-threatening complications.

Adolescent↗
PubMed2005

Hyperosmolar solutions in continuous renal replacement therapy for hyperosmolar acute renal failure: a preliminary report.

OBJECTIVE: To demonstrate the efficacy of hyperosmolar dialysis and prefilter replacement fluid solutions for continuous renal replacement therapies in the correction of hyperosmolar disorders in acute renal failure. DATA SOURCE: An Institutional Review Board-approved pediatric acute renal failure database at the University of Michigan C. S. Mott Children's Hospital. STUDY SELECTION: Three patients were identified meeting the inclusion criteria. The mean serum sodium concentration and plasma osmolality were 158 mmol/L and 357 mOsm/kg, respectively, at the time of initiation of renal replacement therapy. The sodium and/or dextrose concentrations of the dialysate or replacement fluids initially were increased and subsequently decreased to affect the solutions' calculated osmolalities in an effort to control the rate of decline of the patients' measured plasma osmolalities. DATA EXTRACTION: The case patients' serum sodium concentrations and plasma osmolalities were measured. Additionally, the sodium and dextrose concentrations of the dialysate or replacement fluid were recorded and the solutions' osmolalities calculated. DATA SYNTHESIS: The three patients experienced a mean rate of reduction of their serum sodium concentration and plasma osmolality of 0.5 mmol/L/hr and 1.6 mOsm/kg/hr, respectively. CONCLUSIONS: Hyperosmolar dialysis or prefilter replacement fluid solutions can affect a slow decline in both the serum sodium and plasma osmolality in cases of hyperosmolar acute renal failure.

Acute Kidney Injury↗
PubMed2005

Pediatric patients with multi-organ dysfunction syndrome receiving continuous renal replacement therapy.

BACKGROUND: Critical illness leading to multi-organ dysfunction syndrome (MODS) and associated acute renal failure (ARF) is less common in children compared to adult patients. As a result, many issues plague the pediatric ARF outcome literature, including a relative lack of prospective study, a lack of modality stratification in subject populations and inconsistent controls for patient illness severity in outcome analysis. METHODS: We now report data from the first multicenter study to assess the outcome of pediatric patients with MODS receiving continuous renal replacement therapy (CRRT). One hundred twenty of 157 Registry patients (63 male/57 female) experienced MODS during their course. RESULTS: One hundred sixteen patients had complete data available for analysis. The most common causes leading to CRRT were sepsis (N= 47; 39.2%) and cardiogenic shock (N= 24; 20%). Overall survival was 51.7%. Pediatric Risk of Mortality (PRISM 2) score, central venous pressure (CVP), and% fluid overload (%FO) at CRRT initiation were significantly lower for survivors versus nonsurvivors. Multivariate analysis controlling for severity of illness using PRISM 2 at CRRT initiation revealed that%FO was still significantly lower for survivors versus nonsurvivors (P < 0.05) even for patients receiving both mechanical ventilation and vasoactive pressors. We speculate that increased fluid administration from PICU admission to CRRT initiation is an independent risk factor for mortality in pediatric patients with MODS receiving CRRT. CONCLUSION: We suggest that after initial resuscitative efforts, an increased emphasis should be placed on early initiation of CRRT and inotropic agent use over fluid administration to maintain acceptable blood pressure.

Adolescent↗
PubMed2004

Acute renal failure in children and infants.

PURPOSE OF REVIEW: This review provides an overview of various topics related to acute renal failure and summarizes the results of recent advancements of particular significance in the care of children with acute renal failure. RECENT FINDINGS: Over the past two decades, the treatment and prognosis of children with acute renal failure has notably shifted owing to advances in continuous treatment modalities, improvements in vascular access, and increased acknowledgment and understanding of the importance of optimizing nutritional support. SUMMARY: After discussing the various causes of acute renal failure in children and infants, this review focuses on recent advancements in the management of acute renal failure, including acute dialysis modalities and continuous renal replacement therapy.

Acute Kidney Injury↗
PubMed2003

Use of mycophenolate mofetil in steroid-dependent and -resistant nephrotic syndrome.

Cyclosporin (Cs-A) is an effective treatment for difficult cases of nephrotic syndrome (NS), but its use can be complicated by renal toxicity and a high incidence of relapses after withdrawal. We reviewed the charts of 10 Cs-A-dependent patients and 4 patients with steroid-dependent nephrotic syndrome (SDNS) not previously treated with Cs-A therapy. All patients had persistent NS, even after prior treatment with oral cyclophosphamide. Of 10 patients treated with Cs-A, 4 had surveillance renal biopsies consistent with Cs-A toxicity, and 8 of 10 had interstitial fibrosis prior to mycophenolate mofetil (MMF). Patients were treated with MMF, at 1,200 mg/m(2) per day, in an attempt to allow weaning of Cs-A and/or steroid therapy, and reduce the frequency of relapses. Overall, a significant decrease in frequency of relapses was noted after initiation of MMF therapy. In addition, 5 patients were weaned off Cs-A by 1-2 years of follow-up. One patient was weaned off Cs-A and MMF, and remained in complete remission. However, the subgroup of patients with frequently relapsing SDNS not treated with Cs-A appeared to have a reduction in the number of relapses while on MMF that did not reach statistical significance. Two patients with intractable steroid-resistant NS continued to relapse repeatedly on MMF and Cs-A therapy. We conclude that in this small, single-center, uncontrolled experience, MMF therapy in patients with Cs-A-dependent NS appears to be effective in reducing Cs-A exposure. In addition, MMF appears to significantly decrease the frequency of relapses in this patient population. Further controlled studies are warranted to better define the potential efficacy and side effects of long-term MMF therapy in this setting.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed2003

Continuous renal replacement therapy in children up to 10 kg.

BACKGROUND: There is growing use of continuous renal replacement therapy (CRRT) for pediatric patients, but no large studies reporting CRRT use and outcome in young children. We describe a cohort of patients weighing 10 kg or less who underwent CRRT at five US children's hospitals between 1993 and 2001. METHODS: We reviewed records of 85 patients weighing 10 kg or less who underwent at least 24 hours of CRRT. We evaluated weight, diagnosis, pressor number, CRRT characteristics, days on CRRT, and outcome (survival to leave intensive care unit versus death). RESULTS: Patients weighed 1.5 to 10 kg (mean, 5.3 +/- 2.8 kg; 16 patients < or = 3 kg). Sixty-nine percent of patients were being administered pressors at the time of CRRT initiation, 88% of patients were administered heparin, and the others were administered citrate or no anticoagulation. Mean blood flow was 48 +/- 24 mL/min (range, 15 to 106 mL/min) or 9.5 +/- 4.2 mL/min/kg. Six hundred fifty-five patient-days of therapy were studied (mean, 7.6 +/- 8.6 d/patient; range, 1 to 46 d/patient). Thirty-two patients (38%) survived; 4 of 16 patients (25%) weighing 3 kg or less survived. The smallest survivor weighed 2.3 kg. Overall, survivors and nonsurvivors showed no significant difference in weight, days on CRRT, or pressor number. However, for patients weighing more than 3 kg, 28 of 69 patients (41%) survived, and mean pressor number was lower for survivors versus nonsurvivors (0.96 +/- 1.1 versus 1.6 +/- 1.0 pressors; P < 0.03). CONCLUSION: CRRT is feasible and useful in children weighing 10 kg or less. Hemodynamic instability requiring pressor support neither precludes successful CRRT nor adversely affects survival. After CRRT, the survival rate in children who weigh 3 to 10 kg is similar to that in older children and adolescents.

Acute Kidney Injury↗
PubMed2003

Renal failure and renal replacement therapy.

Continuous renal replacement therapy is an effective means for fluid and solute management in ARF/MOSF. Prospective studies have examined issues of anticoagulation, the impact of replacement/dialysis, the effects of bicarbonate-versus lactate-based solutions, and nutritional and medication clearance. Speculation and bias exists concerning when and for what indications CRRT should be initiated. Many clinicians, supported by data from Ronco and Goldstein, would contest that early institution is better if the risks (eg, access, anticoagulation) are minimal and the possible benefits are maximal. The authors, examining the issues as an intensivist and as a nephrologist, believe that early institution, aggressive replacement/dialysis, and use of citrate-based replacement fluids provide substantive advantages. With the advent of Ronco's recent data on sepsis managed with filtration and plasma absorption, the indication for use of CRRT in MOSF may become more evident regardless of the presence or absence of ARF.

Acute Kidney Injury↗
PubMed2003

Pediatric convective hemofiltration: Normocarb replacement fluid and citrate anticoagulation.

BACKGROUND: Continuous venovenous hemofiltration (CVVH) may be preferable over continuous venovenous hemodialysis (CVVHD) in sepsis; however, CVVH use is limited by the lack of commercially produced bicarbonate replacement solutions in the United States. Anticoagulation used for hemofiltration traditionally has been either heparin or citrate based, but to date, citrate protocols have been used predominately in CVVHD. When CVVH has been used with citrate anticoagulation, replacement solutions have had to be custom made in the pharmacy. METHODS: We describe a protocol used in a series of 9 children with sepsis who underwent CVVH with the use of a commercially available bicarbonate solution (Normocarb; Dialysis Solutions Inc, Richmond Hill, Ontario, Canada) and a commercially available citrate solution (Anticoagulant Citrate Dextrose Solution Formula A [ACD-A]; Baxter Health Care, Deerfield, IL). This simplified approach to citrate anticoagulation with CVVH used Normocarb as a prefilter replacement solution under provisions of the 1997 Food and Drug Administration Modernization Act. RESULTS: All patients had acceptable levels of solute and ultrafiltration clearance with this approach. CVVH circuit life averaged 71 hours (range, 37 to 131 hours), influenced in part by the industry recommendation to change the circuit at 72 hours, whereas no complications from this protocol were identified. CONCLUSION: Similar to CVVHD, this protocol is effective and simple in its components, using industry-produced solutions, avoiding the need for pharmacy-made solutions, and limiting cost and potential risk for compounding errors. Although not the purpose of this report, the patient survival rate was 55%.

Adolescent↗
PubMed2002

Pharmacokinetics of darbepoetin alfa in pediatric patients with chronic kidney disease.

Darbepoetin alfa is a novel erythropoiesis-stimulating protein with a two- to threefold longer half-life than recombinant human erythropoietin (epoetin) in adult patients with chronic kidney disease (CKD). This randomized, open-label, crossover study was conducted to determine the pharmacokinetic profile of darbepoetin alfa in pediatric patients with CKD. Twelve patients 3-16 years of age with CKD were randomized and received a single 0.5 micro g/kg dose of darbepoetin alfa administered intravenously (IV) or subcutaneously (SC). After a 14- to 16-day washout period, patients received an identical dose of darbepoetin alfa by the alternate route. After IV administration, the mean clearance of darbepoetin alfa was 2.3 ml/h per kg, with a mean terminal half-life of 22.1 h. After SC administration, absorption was rate limiting, with a mean terminal half-life of 42.8 h and a mean bioavailability of 54%. Comparison of these results with those from a previous study of darbepoetin alfa in adult patients indicated that the disposition of darbepoetin alfa administered IV or SC is similar in adult and pediatric patients, although absorption may be slightly more rapid in pediatric patients after SC dosing. The mean terminal half-life of darbepoetin alfa in this study was approximately two- to fourfold longer than that previously reported for epoetin in pediatric patients.

Adolescent↗
PubMed2002

Pediatric hemofiltration: Normocarb dialysate solution with citrate anticoagulation.

Fourteen children, newborn to 17 years of age, underwent continuous veno-venous hemofiltration with dialysis (CVVHD), using a new FDA-approved bicarbonate-based calcium-free dialysis solution (Normocarb) in combination with citrate anticoagulation. Dialysis prescription included use of the PRISMA system (Gambro, Lakewood, Colo., USA), with ACD-A (Baxter, Deerfield, Ill., USA) for anticoagulation and Normocarb (Dialysis Solution, Richmond Hills, Ontario, Canada) for dialysate. Diagnosis included 11 children with sepsis and 3 children with tumor lysis syndrome. Mean weight was 31.6+/-4.7 kg (range 3.7-62 kg) and average length of therapy was 11.4+/-3.7 days (range 6 h to 67 days). Length of circuit patency was 71.3+/-7.2 h (range 6 h to 127 h), which was influenced in part by a decision to change circuits at 72 h as per manufacturer's recommendation. No bleeding occurred. This protocol utilizes industry-manufactured CVVHD machinery with both thermic and ultrafiltration control, with an effective anticoagulation protocol, and industry-produced bicarbonate dialysate. The use of industry machinery and solutions allows for consistent industrial quality assurance standards. This potentially may decrease the cost of therapy and minimize the risk of pharmacy errors that can occur with pharmacy-made dialysis solutions.

Adolescent↗
PubMed2002

Plasmapheresis and renal replacement therapy in children.

The use of extracorporeal techniques for the treatment of pediatric diseases has expanded dramatically in the past decade. During this time, experience with both plasmapheresis and renal replacement therapy has become commonplace in ICUs and nephrology programs throughout the world. The indications for these therapies range through treatment of vasculitis, drug removal, support from inborn error metabolism, multiorgan system failure, primary renal disease, and sepsis. Because these therapies are somewhat intermingled based on the commonality of the need for vascular access, extracorporeal blood volumes, and bedside nursing support, and furthermore because the indications for these may overlap, these therapies are often used in tandem or parallel to support the child with illness.

Catheters, Indwelling↗
PubMed2001

Improved growth in young children with severe chronic renal insufficiency who use specified nutritional therapy.

Growth in children with chronic renal failure caused by polyuric, salt-wasting diseases may be hampered if ongoing sodium and water losses are not corrected. Twenty-four children were treated with polyuric chronic renal insufficiency (CRI; creatinine clearance <65 ml/min per 1.73 m(2)) with low-caloric-density, high-volume, sodium-supplemented feedings. Subsequent growth was compared with that of children in two control groups: a national historic population control from the US Renal Data System database (n = 42), and a literature control (n = 12). Members of the three groups were 81 to 96% white, and 58 to 70% were boys. Obstructive uropathy and dysplasia were the cause of CRI in 92% of the treatment group, 75% of the literature control group, and 30% of the population control group. Treatment effect was assessed in a multivariate, retrospective analysis of the height standard deviation score (SDS), simultaneously controlling for the severity of disease by renal replacement therapy, primary cause of CRI, and initial height SDS. The change in SDS (Delta SDS) for height by regression analysis at 1 yr was significantly greater by +1.37 in the treatment group versus the population control (P = 0.017). The 2-yr height Delta SDS by regression analysis adjusted for creatinine clearance was significantly greater by +1.83 in the treatment group versus the literature control (P = 0.003). Nutritional support with sodium and water supplementation can maintain or improve the growth of children with polyuric, salt-wasting CRI. This inexpensive intervention may delay the need for renal replacement therapy, growth hormone treatment, or both in many of these children and may be used in any clinical setting.

Body Height↗