Population Pharmacokinetic Modeling and Simulations of Imipenem in Burn Patients With and Without Continuous Venovenous Hemofiltration in the Military Health System.

Continuous venovenous hemofiltration (CVVH) is a life-sustaining procedure in patients with severe burns and acute kidney injury. Physiologic changes from burn injury and use of CVVH may alter imipenem pharmacokinetics (PK). We aimed to compare imipenem clearance (CL) in burn patients with and without CVVH, determine the effect of burn on imipenem volume of distribution (CVVH, n = 12; no CVVH, n = 11), in combination with previously published models. Model qualification was performed with standard diagnostics and comparing predicted PK parameters/time-concentration profiles with those in the existing literature. Monte Carlo simulations were conducted to evaluate the probability of target attainment. A 2-compartment model best described the data. Utilizing albumin as a covariate on volume parameters and leveraging the clearance model from prior literature, our model predicted imipenem central volume and CL within a 10% margin of error across healthy, renally impaired, and burn populations. We provide direct comparison of imipenem CL in burn patients with and without CVVH. Notably, there was no significant difference. Large imipenem Vd in patients with severe burns is likely explained by increased capillary permeability, for which serum albumin may be a reasonable surrogate. Dosing 500 mg every 6 hours is adequate for burn patients on renally dosed CVVH; however, suspicion of augmented renal clearance or patients placed on CVVH without renal impairment may necessitate dosing of 1000 mg every 6 hours.

Venoarterial extracorporeal membrane oxygenation for postcardiotomy cardiogenic shock-A six-year service evaluation.

Only a small number of English hospitals provide postcardiotomy venoarterial extracorporeal membrane oxygenation (VA-ECMO) and there are doubts about its efficacy and safety. The aim of this service evaluation was to determine local survival rates and report on patient demographics. This was a retrospective service evaluation of prospectively recorded routine clinical data from a tertiary cardiothoracic center in the United Kingdom offering services including cardiac and thoracic surgery, heart and lung transplantation, venovenous extracorporeal membrane oxygenation (VV-ECMO) for respiratory failure, and all types of mechanical circulatory support. In six years, 39 patients were supported with VA-ECMO for refractory postcardiotomy cardiogenic shock (PCCS). We analyzed survival data and looked for associations between survival rates and patient characteristics. The intervention was venoarterial-ECMO in patients with PCCS either following weaning from cardiopulmonary bypass or following a trial of inotropes and intra-aortic balloon counterpulsation on the intensive care unit. 30-day, hospital discharge, 1-year and 2-year survivals were 51.3%, 41%, 37.5%, and 38.5%, respectively. The median (IQR [range]) duration of support was 6 (4-9 [1-35]) days. Nonsurvival was associated with advanced age, shorter intensive care length of stay, and the requirement for postoperative hemofiltration. Reasonable survival rates can be achieved in selected patients who may have been expected to have a worse mortality without VA-ECMO. We suggest postoperative VA-ECMO should be available to all patients undergoing cardiac surgery be it in their own center or through an established pathway to a specialist center.

Evaluation of HVHF for the treatment of severe acute pancreatitis accompanying MODS.

Systemic inflammatory response syndrome (SIRS) prevention is key to severe acute pancreatitis (SAP) treatment and the assessment of high-volume hemofiltration (HVHF) for treating SAP accompanying multiple organ dysfunction syndromes.In this prospective controlled study, 40 SAP patients were divided into 2 groups: control (n = 22, treated with fasting, decompression, and intravenous somatostatin) and HVHF (n = 18, HVHF administration in addition to the treatment in the control group) groups; and were assessed for serum and urine amylase, WBC, C-reactive protein (CRP), and hepatic and renal functions. Vital signs and abdominal symptoms were recorded, and complications and mortality were analyzed.APACHE II scores in the HVHF group were significantly lower than in the control group at 3 and 7 days (6.3 ±â€Š1.7 vs 9.2 ±â€Š2.1 and 3.3 ±â€Š0.8 vs 6.2 ±â€Š1.7, respectively). Compared with controls, serum, and urine amylase, WBC, CRP, and organ functions significantly improved after HVHF treatment. Meanwhile, mortality (16.7% vs 31.8%) and complication (11.1% vs 40.9%) rates were significantly reduced.The other clinical parameters were significantly ameliorated by HVHF. HVHF rapidly reduces abdominal symptoms and improves prognosis, reducing mortality in SAP patients; and is likely through systemic inflammatory response syndrome attenuation in the early disease stage.

Epidemiology of augmented renal clearance in mixed ICU patients.

BACKGROUND: Augmented renal clearance (ARC) or renal hyperfiltration is increasingly reported in intensive care unit (ICU) patients. The goal of this analysis was to study the epidemiology of ARC in a cohort of mixed ICU patients METHODS: Single center retrospective cohort study of adult ICU patients (12/2008-2/2010). When data were available, urinary creatinine clearance (CLCR) was calculated for all patients throughout their ICU stay. ARC was defined as a body surface adjusted CLCR≥130 mL/min/1.73m2. We sought to study the incidence of ARC and identify patient characteristics associated with ARC. RESULTS: A total of 1081 patients were included in the analysis, generating 4472 ICU patient days. Median age was 62 y (IQR 50-72), and 63% were male. The initial CLCR was 86 (39-151) mL/min and the maximal CLCR was 145 (76-237) mL/min. ARC occurred in 55.8% of patients, and was about as frequent in men and women (37%% vs. 35%%, P=0.73). Patients with ARC were younger (57 vs. 67 years, P<0.001) and were less frequently treated with vasopressors (27% vs. 39%, P<0.01). ARC incidence was 36.6 ARC days per 100 ICU days. ARC throughout the ICU stay occurred in 32.8% of patients. CONCLUSION: ARC was a frequent finding in this cohort of ICU patients, with more than half of the patient expressing ARC at least once during their ICU stay, and an incidence of 36.6 ARC days/100 patient days.

A prevalence survey of intravascular catheter use in a general hospital.

PURPOSE: Survey of intravascular catheter management is an essential step in the control and prevention of catheter-related infection. In recent years, most surveillance studies only included catheters from intensive care units (ICUs). Data regarding the level of care and adherence to international guidelines in a whole general institution are scarce. Our objective was to evaluate the care situation of intravascular catheters in our adult units of a General Hospital. METHODS: We surveyed adults hospitalized in non-psychiatric/maternity wards. In a week, a nurse visited all the adult hospitalized patients. Data were registered in a protocol that included variables, such as no. of catheters, location of catheter, type of catheter, date of placement and the need of an indication of each catheter in the visit day. RESULTS: We included in the study a total of 753 adult patients. Of them, 653 (86.7%) had one or more inserted catheters at the moment of the study visit (total: 797 catheters). Of all the catheters, 144 (18.0%) were central venous catheters and 653 (81.9%) were peripheral lines. The hospitalization units where the patients were admitted were ICU, 52 (6.9%); and non-ICU, 601 (92.0%). There were 183 (22.9%) catheters with no need to remain in place in the day of the study. Overall, we found 464 (71.0%) patients with one or more opportunities for catheter care improvement. CONCLUSIONS: A rapid survey of the care situation of intravascular catheters is feasible and easy to do with our methodology. The data show great opportunity for improvement, mainly in the non-ICU areas.

Prognostic factors, long-term survival, and outcome of cancer patients receiving chemotherapy in the intensive care unit.

Prognostic factors and outcomes of cancer patients with acute organ failure receiving chemotherapy (CT) in the intensive care unit (ICU) are still incompletely described. We therefore retrospectively studied all patients who received CT in any ICU of our institution between October 2006 and November 2013. Fifty-six patients with hematologic (n = 49; 87.5 %) or solid (n = 7; 12.5 %) malignancies, of which 20 (36 %) were diagnosed in the ICU, were analyzed [m/f ratio, 33:23; median age, 47 years (IQR 32 to 62); Charlson Comorbidity Index (CCI), 3 (2 to 5); Simplified Acute Physiology Score II (SAPS II), 50 (39 to 61)]. The main reasons for admission were acute respiratory failure, acute kidney failure, and septic shock. Mechanical ventilation and vasopressors were employed in 34 patients (61 %) respectively, hemofiltration in 22 (39 %), and extracorporeal life support in 7 (13 %). Twenty-seven patients (48 %) received their first CT in the ICU. Intention of therapy was cure in 46 patients (82 %). Tumor lysis syndrome (TLS) developed in 20 patients (36 %). ICU and hospital survival was 75 and 59 %. Hospital survivors were significantly younger; had lower CCI, SAPS II, and TLS risk scores; presented less often with septic shock; were less likely to develop TLS; and received vasopressors, hemofiltration, and thrombocyte transfusions in lower proportions. After discharge, 88 % continued CT and 69 % of 1-year survivors were in complete remission. Probability of 1- and 2-year survival was 41 and 38 %, respectively. Conclusively, administration of CT in selected ICU cancer patients was feasible and associated with considerable long-term survival as well as long-term disease-free survival.

Does diabetic status in the ICU predict haemofiltration requirement? The haemofiltration in the ICU and diabetic status (HIDS) study.

Diabetes is already a major health burden and prevalence is expected to double by 2025. The impact of diabetes and clinical outcomes in the intensive care unit is an evolving area of research. This study seeks to identify whether diabetic status is an independent risk factor for haemofiltration. This is a retrospective cohort study. All unique patients from a seven-year period from 2004 to 2010 at a major intensive care unit in Melbourne, Australia were analysed using multivariate regression to look for an association between diabetic status and haemofiltration. After exclusion criteria there were 7262 patients, 1674 with a history of diabetes (median age of 69, 66.72% male) and 5588 without a history of diabetes (median age 64, 64.13% male). Diabetic status was an independent risk factor (odds ratio 1.401, 95% confidence interval 1.079 to 1.820, P=0.011) for haemofiltration. Further research may identify intensive care unit-based renoprotective measures specifically for patients with diabetes.

[Surveying the status of continuous blood purification technology application in Chinese pediatric intensive care unit].

OBJECTIVE: To learn application status of continuous blood purification (CBP) in pediatric intensive care unit (PICU), to provide reference to promote the development of CBP technology. METHOD: The survey of CBP application was conducted using questionnaire in 40 hospitals providing intensive care, which included children's hospitals and the pediatric sections of general hospitals from 28 provinces/municipalities/autonomous regions in China during March to July of 2012. RESULT: Totally 38 hospital replied, 25 hospitals carried out CBP technology, first carried out in 1997, the median year was 2008, 21 hospitals' PICU could independently carry out CBP device, 18 hospitals had the nurses who could professionally operate, routinely maintain the device. Continuous veno-venous hemodiafiltration was the largest implementation mode of CBP, accounting for 51.9%. Twenty-three hospitals used ordinary heparin, and 2 hospitals used low molecular weight heparin; 21 hospitals chose activated partial thromboplastin time as the coagulation testing, due to lack of equipment, only four hospitals chose activated clotting time as coagulation testing. Only 3 hospitals could apply before and after dilution joint technology. Kidney failure is still the disease accounting for the highest proportion of diseases requiring CBP application, accounting for 38.1%, followed by sepsis, 19.1%, drug poisoning 16.7%. CONCLUSION: CBP started 10 years ago, and got attention and promotion nearly five years ago in China, but the associated personnel, equipment were inadequate, anticoagulation, before and after dilution and other technical applications were not complete enough, high volume hemofiltration mode was seldom used.

Does removing Mannitol and Voluven from the priming fluid of the cardiopulmonary bypass circuit have clinical effects?

The Auckland Hospital cardiothoracic unit recently removed Mannitol and Voluven from its Plasma-lyte-based cardiopulmonary bypass (CPB) priming fluid. Like with any change to practice, a comprehensive audit should be performed to identify positive or negative effects. The aim of this retrospective analysis was to investigate the effect of changing the CPB prime constituents on fluid balance and clinical outcome parameters. Clinical records were reviewed for 100 consecutive patients undergoing primary, isolated coronary artery bypass grafting (CABG), 50 patients before the prime change and 50 after. All data were collated into a central database for analysis. Mean arterial pressure while on bypass was higher in the new prime group (61.5 mmHg versus 57.5 mmHg, p = .002). There was no significant difference in hematocrit, hemoglobin, serum sodium, serum potassium, or creatinine postoperatively between groups. In regard to important outcomes such as postoperative weight and fluid balance, time on ventilation, length of stay in the intensive care unit (ICU) or hospital, and mortality, there were no significant differences. Interestingly, new prime group spent a smaller proportion of their time in the ICU on mechanical ventilation (23% versus 36%, p = .022). Mannitol and Voluven, like with all drugs, carry their own potential adverse effects. This study demonstrates that removing Mannitol and Voluven from priming fluid did not have any detrimental effect on electrolytes, fluid status, and other important outcomes in this consecutive series of patients having primary isolated CABG surgery. The risk-benefit balance combined with the obvious economic benefit clearly favors removing Mannitol and Voluven from priming fluids.

Prevalence of renal replacement therapy in Veneto for 2008, 2009 and 2010.

The aim of this section is to provide descriptive data for end-stage renal disease (ESRD) in the Veneto Region (Italy). Data were obtained from the Veneto Dialysis and Transplantation Registry (VDTR). Patients were considered to be prevalent renal replacement therapy (RRT) patients if alive on 31 December of each year examined. Prevalence is expressed per million population (pmp). The trend for prevalence of each treatment in the period examined was estimated by random effects longitudinal logistic regression. Prevalence of RRT in Veneto in the years 2008, 2009 and 2010 was 888, 923 and 950 pmp, respectively. The prevalence of RRT patients by treatment modality showed a slight increase for hemodialysis, notable stability for peritoneal dialysis and a more pronounced increase for transplantation. Every year, about 10% of peritoneal dialysis patients shifted to hemodialysis, and 12% received a transplant. The transition probability from hemodialysis to peritoneal dialysis was negligible, and less than 5% of hemodialysis patients received a transplant. The probability of returning to hemodialysis after having received a transplant was less than 2% a year. Bicarbonate hemodialysis slowly increased from 1998 to 2010, both in percentage and in prevalence per million population; conversely, hemodiafiltration (HDF) showed a mild but constant decrease. Automated peritoneal dialysis (APD), which was quantitatively almost negligible in 1998, reached the same level as continuous ambulatory peritoneal dialysis (CAPD) in 2010. The prevalence of patients undergoing living donor transplants almost doubled in the period 1998-2010. The increase of prevalence over time was not proportional for the 3 modalities of RRT: hemodialysis prevalence grew slowly, peritoneal dialysis prevalence remained stable, and renal transplant prevalence quickly increased.

The Hemobag: the modern ultrafiltration system for patients undergoing cardiopulmonary by pass.

BACKGROUND: The return of extracorporeal circuit blood at the termination of cardiopulmonary bypass (CPB) is an important feature of blood conservation during cardiac surgery procedures globally. We report our initial clinical evaluation of the Hemobag system a blood-salvaging device designed for whole blood recovery of residual post-CPB volume. METHODS: Residual whole blood is hemoconcetrated through the multipass "recovery loop" circuit separate from the CPB and collected in the Hemobag System. This allows the surgeons to continue with surgery, decannulate, and administer protamine simultaneously while the Hemobag is in use and the CPB circuit remains safely primed. We have compared 25 patients receiving the Hemobag to a control group of 25 patients treated with the cell washer that represented our previous standard of care method of circuit blood-salvaging technique. RESULTS: The Hemobag system provided significantly higher hemoglobin, hematocrit, fibrinogen, albumin, and total protein levels in the final product reducing the amount of wasted autologous blood cells. There were no device-related complications. There were no significant differences in terms of blood utilization, chest tube drainage and clinical outcomes over the entire postoperative period among groups. CONCLUSIONS: These results suggest that the Hemobag system is a safe and efficient method to multipass hemoconcentrate the residual diluted blood of the CPB circuit. The Hemobag has demonstrated its ability to maximize the composition of the residual CPB volume to achieve the best possible post-CPB hemoglobin, plasma protein and coagulation factors profile for the patient respect to CW.

Perfusion techniques toward bloodless pediatric open heart surgery.

There continues to be evidence regarding the negative impact of blood transfusion on morbidity and mortality in the adult literature, including infection risk, increased hospital and intensive care length of stay, and costs. More effort has been put into reducing the use of blood components in adult surgical centers but blood transfusions continue to be used frequently in pediatric centers. From 2002 through 2005, we embarked on a mission of reduced prime volume in an effort toward bloodless cardiac surgery to meet the needs of the Jehovah's Witness patient. The same bloodless surgical and perfusion techniques were applied to all patients undergoing cardiopulmonary bypass beginning in 2006. Circuit size was minimized and acute normovolemic hemodilution (ANH) was considered and attempted more often, especially if a re-operation. Retrograde arterial prime (RAP) and venous antegrade prime (VAP), dilutional or balanced ultrafiltration during cardiopulmonary bypass, modified arteriovenous ultrafiltration post bypass, and cell salvage of remaining circuit contents after flushing with crystalloid were recorded. ANH, RAP, and VAP, separately or in combination, were used less than 1% of the time prior to 2006. From 2006-2008 ANH was performed on 42% of the patients and RAP/ VAP was performed on 70% of the patients. From 2006-2008, 43% (287 of 662) of the open heart surgeries were performed bloodless in the operating room versus 30% (193 of 633) from 2003-2005. Bloodless surgery more than doubled for the 0-6, 6-15, and 15-20 kg groups from 3.5%, 23%, and 23% respectively in 2003-2005 to 9%, 44%, and 58%, respectively in 2006-2008. With the cooperation of the entire cardiac surgical team, bloodless open heart surgery is achievable in a pediatric cardiac surgical center, including neonates.

Variations in the application of various perfusion technologies in Great Britain and Ireland--a national survey.

In an attempt to reduce the negative sequelae of cardiopulmonary bypass (CPB), a variety of new technologies have been created. This study investigates variations in the application of these technologies throughout Great Britain and Ireland (GB & I). All perfusion departments within GB & I were surveyed about equipment and technologies used in CPB. Eighty-five percent of units use a standard arterial line filter in all cases. Forty percent of units occasionally use leukocyte-depleting filters in various sites within the circuit. Sixteen percent always use some element of heparin-bonded circuit, but 62% never use them. Twenty-five percent use solely rotary pumps, 18% use solely centrifugal pumps, and 56% use both. Finally, 20% are now using minimal extracorporeal circulation in certain clinical scenarios. These decisions are most frequently affected by clinician preference and cost. This survey has highlighted significant variation in the utilization of various technologies used in CPB. While some variation between centers is to be expected, as innovative technologies are adopted at varying rates, surveys such as this are useful for alerting clinicians to gaps between evidence-based knowledge and clinical practice.

Regional anticoagulation and antiaggregation for CVVH in critically ill patients: a prospective, randomized, controlled pilot study.

BACKGROUND: The aim of this study is to assess the efficacy and clinical safety of regional anticoagulation (heparin pre-filter plus post-filter protamine) plus antiaggregation (pre-filter prostacyclin) [Group 1 (G1)] vs. only systemic heparin anticoagulation without antiaggregation [Group 2 (G2)] in critically ill patients with acute renal failure undergoing continuous veno-venous haemofiltration (CVVH). METHODS: One hundred and ten patients were randomized in a prospective, controlled pilot study. G1 patients received 1000 U/h pre-filter heparin, 10 mg/h post-filter protamine sulphate and 4 ng/kg/min pre-filter prostacyclin, while G2 patients received 1000 U/h pre-filter heparin. The haemofilter transmembrane pressure (TMP) and lifespan, as well as the platelet count were observed 1 h before, and at 6, 12, 18, 24 and 36 h from the beginning of CVVH. RESULTS: Haemofilter TMP remained unchanged in G1 while it increased up to three times in G2 (P=0.0002). The median filter lifespan was 68 h in G1 and 19 h in G2. The rate of spontaneous circuit failure was 24% in G1 and 93% in G2 (P=0.0001). The platelet count was stable over the treatment period in G1 while in G2 it decreased progressively (P=0.0073). CONCLUSION: In critically ill patients suffering from acute renal failure, regional anticoagulation with pre-filter heparin and post-filter protamine plus antiaggregation during CVVH is a simple and safe procedure that prevents increases in filter TMP and increases circuit life time compared with systemic anticoagulation with pre-filter heparin only.

Renal replacement therapy for acute kidney injury in Australian and New Zealand intensive care units: a practice survey.

BACKGROUND: There are few published data on the practice of renal replacement therapy (RRT) in Australian and New Zealand intensive care units. These data are essential for designing trials to compare new treatment approaches with "standard care". DESIGN: A prospective survey of RRT practice in ICUs interested in participating in the Australian and New Zealand Randomised Evaluation of Normal vs. Augmented Level (RENAL) Replacement Therapy in ICU Trial. SETTING AND PARTICIPANTS: 34 ICUs in Australia and New Zealand. OUTCOME MEASURES: Information on choice of therapeutic modality, technique, dose prescription, dose adjustment, technology, and replacement fluid composition before the initiation of the trial. RESULTS: All ICUs used continuous veno-venous RRT (CRRT) as the therapy of first choice. The most common technique, continuous veno-venous (CVV) haemodiafiltration, was used in 62% (21/34) of ICUs, followed by CVV haemofiltration in 35%, (12/34) and CVV haemodialysis in 3% (1/34). Replacement fluid was given prefilter (pre-dilution) in most cases (94%). Lactate-based replacement fluid or dialysate accounted for 55% of all commercial fluid supplied by pharmacies to participating ICUs, bicarbonate-based fluid for 43% and citrate-based fluid for 2%. In all ICUs, CRRT was prescribed by critical care physicians alone, according to unit policy. The effluent dose varied from 1.5 L/h to 4 L/h, and was not adjusted to body weight in any of the ICUs surveyed. The median (and mode) effluent dose was a fixed regimen of 2 L/h. The most commonly used machine was the Gambro Prisma (38%), followed by the Gambro AK 10 blood module combined with volumetric fluid infusion pumps (29%), and the Kimal Hygieia (18%). The median (and mode) blood flow was 200mL/min. Given the information supplied on pre-dilution rates, the median blood flow, and estimates of haematocrit and body weight based on previous surveys, the "typical" prescribed CRRT urea clearance dose ("standard") before the RENAL trial was estimated to be approximately 25 mL/kg/h. CONCLUSIONS: These findings provide insight into RRT practice in ICUs in Australia and New Zealand, as well as useful data to assess whether the control group in the RENAL trial receives "standard" therapy as delivered in Australian and New Zealand trial centres at the time.

Renal replacement therapy for acute renal failure: a survey of practice in adult intensive care units in the United Kingdom.

This study surveyed current practice in adult intensive care units in the United Kingdom in three key areas of renal replacement therapy when used for acute renal failure: type of therapy used, typical treatment dose and anticoagulation. Responses were received from 303 (99%) of the 306 intensive care units. 269 units (89%) provide renal replacement therapy for acute renal failure. Most (65%) use continuous veno-venous haemofiltration as first-line therapy in the majority of patients, though continuous veno-venous haemodiafiltration is used by 31% of units. For haemofiltration, the median typical treatment dose (interquartile range [range]) is 32 ml.kg(-1).h(-1) (28.6-35.7 [14.3-85.7]), with 49% using a treatment dose of 35 ml.kg(-1).h(-1) or greater. For haemodiafiltration, the median typical treatment dose (interquartile range [range]) is 44 ml.kg(-1).h(-1) (28.6-57.1 [21.4-120.7]), with 67% using a treatment dose of 35 ml.kg(-1).h(-1) or greater. The vast majority of intensive care units use intravenous unfractionated heparin (96%) or epoprostenol (88%) for anticoagulation. Dosage and monitoring of these two agents vary markedly between units. No units use citrate anticoagulation. These results reveal a wide variety of practice in the delivery of renal replacement therapy between intensive care units in the United Kingdom.

Exploring CRRT practices in ICU: a survey of Canadian hospitals.

BACKGROUND: Continuous renal replacement therapy (CRRT) is a highly specialized therapy not only for patients with acute renal failure, but also for patients with other critical conditions. The nursing work involved in CRRT is complex and the learning requirements are challenging to sustain ongoing competence. There are also adverse events associated with CRRT, such as those resulting from the anticoagulation therapy. Limited nursing literature is available regarding the use of CRRT by nurses in Canadian intensive care units. METHODS: In 2005, the authors conducted a national survey of CRRT nursing practices with nurse educators in intensive care units. The survey had fixed choice, as well as open-ended questions exploring various aspects of CRRT implementation, including education provided and adverse events experienced by patients. RESULTS: Of the 53 teaching and non-teaching hospitals that were sent the survey, 50 replied (94% response rate). Thirty-four of the sites used CRRT. The results reported here represent the findings from the survey questions pertaining to education and adverse events only. CONCLUSION: The results indicate that education, continuing competence, and prevention and management of adverse events, such as bleeding and filter clotting, are the major issues related to CRRT nursing practice across Canada.

Late dialysis rate for coronary artery bypass grafting patients with moderate-to-severe renal impairment: comparison between off-pump and conventional method.

BACKGROUND: Whether off-pump coronary artery bypass grafting has a late renal protective advantage over conventional coronary arterial bypass grafting with cardiopulmonary bypass use is controversial. METHODS: From 1997 to 2004, 2102 cases of isolated coronary arterial bypass grafting were collected and analyzed, 1116 (53%) in the cardiopulmonary bypass group and 986 (47%) in the off-pump coronary artery bypass grafting group. Cases were stratified by preoperative estimated glomerular filtration rate into three renal groups: 1012 (48%) in group 1, with glomerular filtration rates > or =60 ml/h, 864 (41%) in group 2, with glomerular filtration rates of 30-60 ml/h, and 226 (10.8%) in group 3, with glomerular filtration rates <30 ml/h, but without dialysis before surgery. RESULTS: The in-hospital mechanical renal replacement therapy rates were 2.0%, 4.6%, and 26.1%, respectively, for the three renal groups that underwent coronary artery bypass grafting with conventional cardiopulmonary bypass, and 1.1%, 3.4%, and 14.0%, respectively for the three renal groups that underwent off-pump coronary artery bypass grafting. After risk adjustment, cardiopulmonary bypass use did not show statistical significance for in-hospital mechanical renal replacement therapy (p=0.314, 0.524, 0.150, respectively, across renal groups 1-3). At the end of the 4-year follow-up period, 99.1%, 97.2%, and 78.6%, respectively, of patients were free of mechanical renal replacement therapy across the three renal groups (p=0.0097 between renal groups 1 and 2; p<0.001 between renal groups 2 and 3). Cox regression analysis for renal groups 2 and 3 revealed that cardiopulmonary bypass use was not a risk factor for mid-term mechanical renal replacement therapy (p=0.452), but preoperative glomerular filtration rate, hypercholesterolemia, insulin-requiring diabetes, young age at surgery, female gender, and in-hospital mechanical renal replacement therapy use were. CONCLUSION: Patient characteristics, rather than operative strategy of using off-pump or conventional coronary artery bypass grafting, influence the mid-term mechanical renal replacement therapy rate for patients with glomerular filtration rates <60 ml/min.