Use Of Hemofiltration Research Articles

Intraoperative haemofiltration during on-pump cardiac surgery at Queen Alia Heart Institute

Background: Objective of the study was to determine the frequency, indications and benefits of utilizing haemofiltration during cardiopulmonary bypass in adult cardiac surgical patients. Methods: This is a prospective observational analysis of data of adult cardiac surgical patients presented for on-pump cardiac surgery in the period between September 2023 and December 2023 at Queen Alia Heart Institute. Data was collected using Google Forms online and was subsequently recorded on Excel sheaths. Patients were divided into two groups: the haemofiltration group and the non-haemofiltration group. Both groups were compared according to perioperative laboratory and clinical variables. Statistical analysis of results using Microsoft excel followed data collection. Ethical committee approval was obtained. Results: Data from 130 adult cardiac surgical patients (105 males and 25 females) enrolled in this analysis showed that haemofiltration was used in 25 patients (19.2%). The most frequent indication for intraoperative haemofiltration was haemodilution in 14 patients (56%). Blood transfusion was needed in 17 (68%) of patients who had haemofiltration and in 35 (33.4%) of patients who did not need haemofiltration. Patients from the haemofiltration group were extubated 5 hours earlier than patients from the non-haemofiltration group, as the duration of mechanical ventilation in the ICU was 17.9 hours in the haemofiltration group versus 24.9 hours in the non-haemofiltration group. The average overall hospital stay was 3 days less in the haemofiltration group. Conclusions: Haemofiltration during cardiopulmonary bypass main indications were severe haemodilution, hyperkalaemia and preoperative renal impairment. The use of haemofiltration during CPB was associated with earlier tracheal extubation and shorter hospital stay.

Con: Modified Ultrafiltration Should Not Be Routinely Used in Adult Cardiac Surgery

CARDIOPULMONARY BYPASS (CPB) is known to induce a systemic proinflammatory state and may contribute to postoperative organ dysfunction, primarily through complement activation secondary to blood passing through an artificial extracorporeal circuit. 1 Hall RI Smith MS Rocker G. The systemic inflammatory response to cardiopulmonary bypass: Pathophysiological, therapeutic, and pharmacological considerations. Anesth Analg. 1997; 85: 766-782 Crossref PubMed Google Scholar , 2 Wang W Huang HM Zhu DM et al. Modified ultrafiltration in paediatric cardiopulmonary bypass. Perfusion. 1998; 13: 304-310 Crossref PubMed Scopus (39) Google Scholar , 3 Thapmongkol S Masaratana P Subtaweesin T et al. The effects of modified ultrafiltration on clinical outcomes of adult and pediatric cardiac surgery. Asian Biomedicine. 2015; 9: 591-599 Crossref Scopus (4) Google Scholar Ultrafiltration may minimize some of the impact of the CPB-induced systemic inflammatory response. 4 Huang H Yao T Wang W et al. Continuous ultrafiltration attenuates the pulmonary injury that follows open heart surgery with cardiopulmonary bypass. Ann Thorac Surg. 2003; 76: 136-140 Abstract Full Text Full Text PDF PubMed Scopus (85) Google Scholar Traditionally, ultrafiltration may be conventional (CUF) or modified (MUF). Conventional ultrafiltration has been employed extensively during CPB, and involves hemoconcentration of both the priming volume and patient's blood volume at any point during CPB. 5 Darup J Bleese N Kalmar P et al. Hemofiltration during extracorporeal circulation (ECC). Thorac Cardiovasc Surg. 1979; 27: 227-230 Crossref PubMed Scopus (30) Google Scholar ,6 Klineberg PL Kam CA Johnson DC et al. Hematocrit and blood volume control during cardiopulmonary bypass with the use of hemofiltration. Anesthesiology. 1984; 60: 478-480 Crossref PubMed Scopus (19) Google Scholar In the early 1990s, Naik et al. introduced the concept of MUF 7 Elliott MJ. Ultrafiltration and modified ultrafiltration in pediatric open heart operations. Ann Thorac Surg. 1993; 56: 1518-1522 Abstract Full Text PDF PubMed Scopus (205) Google Scholar ,8 Andreasson S Gothberg S Berggren H et al. Hemofiltration modifies complement activation after extracorporeal circulation in infants. Ann Thorac Surg. 1993; 56: 1515-1517 Abstract Full Text PDF PubMed Scopus (88) Google Scholar ,9 Naik SK Knight A Elliott MJ. A successful modification of ultrafiltration for cardiopulmonary bypass in children. Perfusion. 1991; 6: 41-50 Crossref PubMed Scopus (164) Google Scholar in which the patient's blood volume is hemoconcentrated after separation from CPB. 10 Wang S Palanzo D Undar A. Current ultrafiltration techniques before, during and after pediatric cardiopulmonary bypass procedures. Perfusion. 2012; 27: 438-446 Crossref PubMed Scopus (40) Google Scholar Naik et al. postulated it may permit blood-free cardiac surgery. 11 Naik SK Knight A Elliott M. A prospective randomized study of a modified technique of ultrafiltration during pediatric open-heart surgery. Circulation. 1991; 84 (III422-31) PubMed Google Scholar Blood is typically removed from the arterial cannula and returned through the venous cannula. Others employ a modified technique in which blood is removed from the right atrium and infused into the aorta, potentially reducing concerns about cerebral shunting. 12 Myers GJ Leadon RB Mitchell LB et al. Simple modified ultrafiltration. Perfusion. 2000; 15: 447-452 Crossref PubMed Scopus (16) Google Scholar

Hemofiltration in the Management of Severe Pediatric Burns: Experience in a UK Burns Centre and Systematic Review.

Pediatric burns are life-threatening injuries due to the acute injury and secondary complications. In acute-phase burns, hypovolemia and vasoconstriction cause renal impairment. Sepsis and multiorgan failure compound the problem resulting in morbidity and mortality. This paper outlines 5 years' experience using hemofiltration in major pediatric burns, and a review of the current literature. Retrospective patient data collection was undertaken identifying relevant pediatric burns undergoing Continuous Veno-Venous Hemofiltration. Data were analyzed to identify demographics, indication, duration of therapy, and outcomes. A systematic review was also performed using PRISMA principles. PubMed, Science Direct, and OVID databases were explored and relevant papers were included. From January 2015 to December 2019, hemofiltration was utilized in five cases. Age range 3 to 15 years (mean: 12), four males/one female, and mean weight 56 kg (12-125 kg). TBSA 21% to 61% (mean: 37.6%), mechanism of injury was scald-60%, flame-40%. Overall survival was 100%. Three patients were filtered for a brief period during the first 24 hours to correct metabolic acidosis and control temperature. Two patients required prolonged therapy. All patients recovered without further long-term renal support. A total of 3814 papers were identified for systematic review. Three were considered relevant for inclusion. This paper reflects the benefits of hemofiltration in the management of severe pediatric burns. Renal replacement therapy is useful in managing metabolic acidosis, temperature control, and renal failure. The current literature supports judicious use on a patient-by-patient basis. Given the lack of evidence in the literature, further studies are required to establish guidelines for the use of hemofiltration in pediatric burns.

Does hemofiltration protect the brain after head trauma? An experimental study in rabbits

BackgroundTraumatic brain injury (TBI) is one of the most frequent and severe neurological diseases. In the last few decades, significant advances have been made in TBI pathophysiology and monitoring, however new treatments have not emerged. Although the central nervous system (CNS) has been historically defined as an immunologically privileged organ, recent studies show the increasingly predominant role of inflammatory and apoptotic phenomena in the pathogenesis of TBI. Inflammatory response mediators can be eliminated with continuous renal replacement therapies (CRRT). Our aim was to investigate whether hemofiltration protects the brain after head trauma in an experimental study in animals.Methods and resultsA model of TBI and CVVH was performed in anesthetized New Zealand white rabbits without acute renal failure. The experimental group TBI ( +)-CVVH ( +) was compared with a TBI ( +)-CVVH (−) and a TBI (−)-CVVH ( +) control groups. Rabbits were assessed immediately (NES1) and 24 h hours after (NES2) TBI and/or CVVH using a functional Neurological Evaluation Score (NES) and histology of the brains after sacrifice. There was evidence to support a difference of NES1 comparing with the TBI (−)-CVVH ( +), but not with TBI ( +)-CVVH (−) with only 15% of the rabbits treated with CVVH and TBI showing a favorable neurological course. The final neurological outcome (mortality at 24 h) was 0%, 22% and 53% in the TBI(−) + CVVH( +), TBI( +)-CVVH(−) and TBI( +)-CVVH( +) groups respectively. The use of hemofiltration before or after TBI did not make a difference in regards the outcome of the rabbits. There was evidence in the histology to support an increase of mild ischemia, hemorrhage and edema in the experimental group compared with the other two groups.ConclusionsCVVH in rabbits without renal failure used with the intention to protect the brain may worsen the prognosis in TBI.

Liberal Use of Hemofiltration to Optimize Volume Status in iPAH Patients Does Not Impair Long-Term Kidney Function

The post-operative phase after LTx for iPAH can be challenging. A restrictive fluid management facilitates unloading of the untrained left ventricle and reduces the risk for reperfusion edema. In our center, hemofiltration (HF) is pre-emptively started when a patient cannot be balanced negatively despite maximal medicamentous effort. It remains unclear whether such a strategy impairs long-term outcomes. iPAH patients transplanted between 2000 and 2018 were included in this retrospective analysis. Data collected included kidney function, immunosuppressive therapy, use of HF, PGD rates, length of mechanical ventilation and survival RESULTS: Within the study period 99 iPAH patients were transplanted in our institution. Preoperative kidney insufficiency was recorded in 21 patients (21%). Estimated glomerular filtration rate decreased from a median of 83 ml/min at arrival in ICU to a median of 62 ml/min two days after LTx. In thirty patients (30%) HF was started within the first 48 hours with a median length of 21 days (10-27). In these patients serum creatinine (1.1 vs 1.8 mg/dL, p<0.001) and blood urea nitrogen (28 vs 35 mg/dL, p<0.001) was significantly higher in the first three postoperative days. All patients could be successfully weaned from HF. No difference was found between the two groups in terms of serum creatinine at 1, 3 and 5 years: 1.12 vs 1.2 mg/dL, 1.12 vs 1.2 mg/dL and 1.14 vs 1.25 mg/dL, respectively. Patients requiring postoperative HF showed comparable long-term rates of higher CKD stages (18%) to the other patients (23%, p=0.99). Multivariable Cox regression revealed that HF was not a risk factor for long-term survival (p=0.127). Long-term survival was excellent with 5-year survival rates of 79% CONCLUSION: A liberal use of HF in the early postoperative period does not impact long-term kidney function. Our data suggest that an aggressive peri-operative fluid management including early implementation of HF leads to excellent long-term outcomes.

The burden of chronic obstructive pulmonary disease in open heart surgery-a retrospective cohort analysis of postoperative complications: STROBE compliant.

Chronic obstructive pulmonary disease (COPD) has a major impact on mortality and morbidity in patients undergoing cardiac surgery. Mortality risk increases by 50% in patients who were re-intubated or required prolonged mechanical ventilation after the operation. The aim of this study was to assess the impact of COPD on the prediction of postoperative complications and outcome including intensive care unit (ICU) and hospital stay, postoperative morbidity and mortality in patients undergoing all types of cardiac surgery.We performed a retrospective cohort analysis of prospectively collected data from a tertiary cardiac surgery department of a university hospital between 2014 and 2016. We divided patients undergoing cardiac surgery into 2 sub-groups – the first – with a clinical diagnosis of COPD (n = 198) and the second comprised all other non-COPD patients (n = 2980).Among patients with COPD a longer intubation time (P = .039), longer ICU stay (P < .001) and longer hospitalization time (P = .006) was noted as compared with non-COPD patients. Patients with COPD required reintubation more often than non-COPD patients, reintubation occurring twice, 19 (9.60%) versus 144 (4.83%) P = .002, reintubation occurring 3 or more times, 7 (3.54%) versus 34 (1.14%) P = .006. Mortality within 30 days after surgery was higher in patients with pulmonary problems before surgery (P = .003). Multivariable logistic regression analysis corrected for interfering variables showed an increased risk of postoperative bronchoconstriction (odds ratio [OR] = 4.40, P = .002), respiratory failure (OR = 1.67, P = .018), atrial fibrillation (OR = 1.45, P = .023), and use of hemofiltration (OR = 1.60, P = .029) for patients with COPD.Patients with COPD undergoing all types of cardiac surgery are at increased risk of respiratory complications and mortality. The occurrence of COPD was associated with longer ICU and hospital stay. In COPD patients, undergoing cardiac surgery, treatment strategies aimed at preventing reintubation and early weaning mechanical ventilation must be employed to reduce postoperative complications.

Cardiopulmonary bypass management and acute kidney injury in 118 Jehovah's Witness patients: a retrospective propensity-matched multicentre cohort from 30,942 patients.

Patients refusing blood products in cardiac surgery present challenges for cardiopulmonary bypass. Accurate detail of the modifiable factors of cardiopulmonary bypass relating to acute kidney injury is previously unreported in this patient population. A total of 118 adult Jehovah's Witness patients refusing transfusion were propensity matched to 118 adult patients accepting transfusion from the 30,942 patients in the Australian and New Zealand Collaborative Perfusion Registry. The primary endpoint was acute kidney injury. Intraoperative and bypass management characteristics were also compared between early (2007-2012) and late (2013-2018) cohorts along with the acceptance or refusal of transfusion. In patients accepting transfusion, 49% received a blood product. In patients refusing transfusion, acute kidney injury was lower (8% vs. 22%; p = 0.003) cell salvage use was higher (70% vs. 22%; p < 0.001), as was use of haemofiltration (8% vs. 4%; p = 0.03) and tranexamic acid in the early period (87% vs. 62%, p = 0.004) but not late (100% vs. 97%; p = 0.15). There was no difference in modifiable cardiopulmonary bypass factors (mean arterial pressure, minimum oxygen delivery (DO2i), retrograde autologous prime, circuit prime volume) between the two groups; however, prime volume decreased and DO2i increased over time for both. Patients refusing transfusion had lower postoperative blood loss (p = 0.02) and shorter postoperative length of stay (p < 0.001) with no difference in morbidity (p = 0.46) or mortality (p = 0.68). Refusal of transfusion in patients undergoing cardiopulmonary bypass was associated with reduced acute kidney injury, hospital stay and postoperative blood loss, while not impacting mortality.

Extracorporeal membrane oxygenator support in infants with systemic-pulmonary shunts

BackgroundManagement of a patent systemic-pulmonary (SP) shunt and the resulting runoff during extracorporeal membrane oxygenation (ECMO) varies among institutions. We have used a strategy of increased flow without surgical reduction of the shunt diameter, and here report our results with this strategy. MethodsIn this database review of 169 successive veno-arterial ECMO runs performed between 2002 and 2013 in infants and neonates, ECMO flow, time to achieve lactate clearance, normal pH, and negative fluid balance were compared in patients with shunts and those without shunts. ResultsFifty-one of 169 infants (30.2%) had a shunt in situ when ECMO was initiated. Significantly higher ECMO flows were maintained in the shunt group compared with the nonshunt group (161 ± 43 mL/kg/minute vs 134 ± 41 mL/kg/minute; P < .001). Infants with shunts had significantly higher pre-ECMO and peak lactate levels (12.4 ± 5.6 mmol/L vs 10.0 ± 6.3 mmol/L; P < .05 and 13.7 ± 4.9 mmol/L vs 11.6 ± 5.5 mmol/L; P < .02, respectively) and required a longer period of support for clearance (median, 28.8 hours [16.1-63.3 hours] vs 17.5 hours [10.8-34.5 hours]; P < .001). Although the absolute rate of lactate clearance was not significantly different between the 2 groups (median, 0.46 mmol/L/hour [0.12-0.72 mmol/L/hour] vs 0.48 mmol/L/hour [0.22-0.86 mmol/L/hour]; P = .139) the presence of a shunt, neonatal age, peak lactate, extracorporeal cardiopulmonary resuscitation, and the use of hemofiltration on ECMO significantly predicted the rate of clearance. Survival to hospital discharge was similar in the shunt and nonshunt groups (49.0% vs 48.3%; P = .932). ConclusionsA strategy of increased ECMO flow without surgically restricting shunt diameter appears to be successful in providing circulatory support in the majority of patients with an SP shunt. Equivalent survival suggests that routine surgical reduction of shunt diameter is not indicated.

The standard of care of patients with ARDS: ventilatory settings and rescue therapies for refractory hypoxemia.

PurposeSevere ARDS is often associated with refractory hypoxemia, and early identification and treatment of hypoxemia is mandatory. For the management of severe ARDS ventilator settings, positioning therapy, infection control, and supportive measures are essential to improve survival.Methods and resultsA precise definition of life-threating hypoxemia is not identified. Typical clinical determinations are: arterial partial pressure of oxygen < 60 mmHg and/or arterial oxygenation < 88 % and/or the ratio of PaO2/FIO2 < 100. For mechanical ventilation specific settings are recommended: limitation of tidal volume (6 ml/kg predicted body weight), adequate high PEEP (>12 cmH2O), a recruitment manoeuvre in special situations, and a ‘balanced’ respiratory rate (20-30/min). Individual bedside methods to guide PEEP/recruitment (e.g., transpulmonary pressure) are not (yet) available. Prone positioning [early (≤ 48 hrs after onset of severe ARDS) and prolonged (repetition of 16-hr-sessions)] improves survival. An advanced infection management/control includes early diagnosis of bacterial, atypical, viral and fungal specimen (blood culture, bronchoalveolar lavage), and of infection sources by CT scan, followed by administration of broad-spectrum anti-infectives. Neuromuscular blockage (Cisatracurium ≤ 48 hrs after onset of ARDS), as well as an adequate sedation strategy (score guided) is an important supportive therapy. A negative fluid balance is associated with improved lung function and the use of hemofiltration might be indicated for specific indications.ConclusionsA specific standard of care is required for the management of severe ARDS with refractory hypoxemia.

PM046 The early use of hemofiltration increases survival in patients with acute renal failure in the setting of intensive cardiac care unit

PM046 The early use of hemofiltration increases survival in patients with acute renal failure in the setting of intensive cardiac care unit

The impact of continuous haemofiltration with high-volume fluid exchange during cardiopulmonary bypass surgery on the recovery of patients with impaired renal function: a pilot randomised trial

There is widespread variability in clinical practice within cardiac surgery units worldwide on the use of haemofiltration. The clinical impact and safety of this modality is, however, unknown. The primary pilot trial objectives were as follows: to assess the feasibility of randomising 60 patients with impaired kidney function undergoing on-pump coronary artery bypass graft (CABG) surgery within 6 months; to assess the suitability and reliability of our chosen outcome measures; to explore issues that may impact on recruitment into a definitive trial; and to undertake an exploratory economic evaluation. A pilot, single-centre, open-label randomised trial. Liverpool Heart and Chest Hospital NHS Foundation Trust between November 2010 and March 2012. Men and women, aged > 18 years of age, undergoing on-pump CABG surgery, who had pre-operative impaired kidney function indicated by an estimated glomerular filtration rate (eGFR) of < 60 ml/minute adjusted for 1.73 m(2) of body surface area. Group 1: patients who received haemofiltration during bypass (experimental group). Group 2: patients who did not receive haemofiltration during bypass (control group). (1) Feasibility outcome measures: barriers to recruitment to a larger trial were documented as observations made during the recruitment period of the trial. Reliability of data collection methods was monitored using a 13-point case record form validation check for data entry against the patient clinical notes and the trial database. (2) The main clinical outcomes were frequency of intensive care unit (ICU) stay of duration > 3 days and the length of ICU stay days. (3) Other clinical outcomes were the need for postoperative haemofiltration in the ICU, mechanical ventilation time, hospital stay, composite of outcome of unfavourable perioperative events and eGFR values at 6 weeks' follow-up. (4) Secondary health economic feasibility outcomes. Recruitment into the pilot trial was from 21 November 2010 to 30 March 2012. Thirty-seven eligible patients were consented and successfully randomised into the trial arms (30%). The main issues impacting on recruitment were the high volume of off-pump CABG surgery within the centre; recruitment being restricted to research nurses' working hours of the week; issues arising associated with the screening process for identifying prospective eligible patients based on eGFR values; protocol deviations/treatment crossovers; and unexpected outbreaks of pandemic influenza and other infectious conditions. The data collection process was sufficiently robust, with few errors detected. The length of ICU stay days was deemed a suitable primary outcome. There was an overall trend towards reduction in the length of ICU stay for patients who were given intraoperative haemofiltration, more so for those with diabetes. The economic evaluation estimated that the incremental costs per person were £1744 lower for the intraoperative haemofiltration group, while the incremental benefits per person increased by 0.11. Given sufficient resources and broadening of the inclusion criteria, the recruitment into a larger multicentre trial is feasible and may demonstrate potential clinical and cost benefits of using intraoperative haemofiltration in this group of patients. However, owing to the small sample size in this pilot trial, no firm conclusions can be drawn from the findings at this stage. The outcomes of this pilot study are very encouraging and suggest that it is feasible to design a continuous superiority trial with the length of ICU stay days or time to tracheal extubation as the primary outcome measure, provided that guidelines for avoiding bias are implemented. An alternative primary outcome measure that avoids bias is mortality. The inclusion criteria should also be widened to include all cardiac surgery patients with impaired renal function. ISRCTN49513454. This project was funded by the NIHR Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 17, No. 49. See the HTA programme website for further project information.

Continuous renal replacement therapy in children after cardiac surgery

The objective was to study the clinical course of children requiring continuous renal replacement therapy (CRRT) after cardiac surgery and to analyze the factors associated with mortality. A prospective observational study was performed that included all children requiring CRRT after cardiac surgery, comparing these patients with other critically ill children requiring CRRT. Univariate and multivariate analyses were performed to determine the influence of each factor on mortality. Eighty-one (4.9%) of 1650 children undergoing cardiac surgery required CRRT; 65 of them (80.2%) presented multiorgan failure. Children starting CRRT after cardiac surgery had lower mean arterial pressure and lower urea and creatinine levels, and were more likely to require mechanical ventilation than other children on CRRT. The incidence of complications was similar. Cardiac surgery increased the probability of requiring CRRT for more than 14 days. Mortality was 43% in children receiving CRRT after cardiac surgery and 29% in other children (P = .05). Factors associated with mortality in the univariate analysis were age less than 12 months, weight less than 10 kg, higher Pediatric Risk of Mortality Score, hypotension, lower urea and creatinine on starting CRRT, and use of hemofiltration. In the multivariate analysis, the only factor associated with mortality was hypotension on starting CRRT (hazard ratio, 4.01; 95% confidence interval, 1.2-13.4; P = .024). Although only a small percentage of children undergoing cardiac surgery required CRRT, mortality in these patients was high. Hypotension at the time of starting the technique was the only factor associated with a higher mortality.

Renal Support for Pediatric Patients With Acute Kidney Injury After Cardiac Surgery. What Do We Know Now?

81 children with a mean age of 50-54 months who received continuous renal replacement therapy (CRRT) after CS. These children had a higher mortality rate (43%) than those who received CRRT for noncardiac causes (4%). There were 14 patients on ECLS with 3 of them having the CRRT circuit directly connecting to the ECLS circuit. CRRT was initiated when the fluid balance was positive and there was oliguria, or a serum creatinine concentration double that of normal levels for age. Compared with patients receiving CRRT for other causes, those with CS had a higher incidence of CRRT, lower blood pressure, a longer duration of CRRT, and more frequent need for mechanical ventilation. Risk factors associated with mortality were hypotension at the start of CRRT, Pediatric Risk of Mortality Score21, and the use of hemofiltration.

Evolution and Mortality Risk Factors in Children With Continuous Renal Replacement Therapy After Cardiac Surgery

Introduction and objectivesTo study the clinical course of children requiring continuous renal replacement therapy after cardiac surgery and to analyze factors associated with mortality. MethodsA prospective observational study was performed that included children requiring continuous renal replacement therapy after cardiac surgery. Univariate and multivariate analyses were performed to determine the influence of each factor on mortality. We compared these patients with other critically ill children requiring continuous renal replacement therapy. ResultsOf 1650 children undergoing cardiac surgery, 81 (4.9%) required continuous renal replacement therapy, 65 of whom (80.2%) presented multiple organ failure. The children who started continuous renal replacement therapy after cardiac surgery had lower mean arterial pressure, lower urea and creatinine levels, and higher mortality (43%) than the other children on continuous renal replacement therapy (29%) (P=.05). Factors associated with mortality in the univariate analysis were age less than 12 months, weight under 10 kg, higher pediatric risk of mortality score, hypotension, lower urea and creatinine levels when starting continuous renal replacement therapy, and the use of hemofiltration. In the multivariate analysis, hypotension when starting continuous renal replacement therapy, pediatric risk of mortality scores equal to or greaterer than 21, and hemofiltration were associated with mortality. ConclusionsAlthough only a small percentage of children undergoing cardiac surgery required continuous renal replacement therapy, mortality among these patients was high. Hypotension and severity of illness when starting the technique and hemofiltration were factors associated with higher mortality.

Evolución y factores de riesgo de mortalidad en niños sometidos a cirugía cardiaca que requieren técnicas de depuración extrarrenal continua

Introduction and objectivesTo study the clinical course of children requiring continuous renal replacement therapy after cardiac surgery and to analyze factors associated with mortality. MethodsA prospective observational study was performed that included children requiring continuous renal replacement therapy after cardiac surgery. Univariate and multivariate analyses were performed to determine the influence of each factor on mortality. We compared these patients with other critically ill children requiring continuous renal replacement therapy. ResultsOf 1650 children undergoing cardiac surgery, 81 (4.9%) required continuous renal replacement therapy, 65 of whom (80.2%) presented multiple organ failure. The children who started continuous renal replacement therapy after cardiac surgery had lower mean arterial pressure, lower urea and creatinine levels, and higher mortality (43%) than the other children on continuous renal replacement therapy (29%) (P=.05). Factors associated with mortality in the univariate analysis were age less than 12 months, weight under 10 kg, higher pediatric risk of mortality score, hypotension, lower urea and creatinine levels when starting continuous renal replacement therapy, and the use of hemofiltration. In the multivariate analysis, hypotension when starting continuous renal replacement therapy, pediatric risk of mortality scores equal to or greater than 21, and hemofiltration were associated with mortality. ConclusionsAlthough only a small percentage of children undergoing cardiac surgery required continuous renal replacement therapy, mortality among these patients was high. Hypotension and severity of illness when starting the technique and hemofiltration were factors associated with higher mortality.Full English text available from: www.revespcardiol.org

Hemofiltration During Cardiopulmonary Bypass Does Not Decrease the Incidence of Atrial Fibrillation After Cardiac Surgery

Atrial fibrillation (AF) occurs in 20%-50% of patients after cardiac surgery and is associated with increased morbidity and mortality. Corticosteroids are reported to decrease the incidence of postoperative AF, presumably by attenuating inflammation caused by surgery and cardiopulmonary bypass (CPB). We hypothesized that hemofiltration during CPB, which may attenuate inflammation, might decrease the incidence of AF after cardiac surgery. This was a retrospective review of patients previously enrolled in a double-blind, placebo-controlled trial evaluating the effects of perioperative steroid therapy and hemofiltration during CPB on duration of postoperative mechanical ventilation. In that study, 192 patients undergoing cardiac surgery were randomized to 1 of 3 groups: controls (placebo), hemofiltration during CPB, or perioperative steroid therapy. Patient records were reviewed to determine the incidence of new onset AF defined as any electrocardiogram evidence of AF or AF diagnosed by the patients' clinicians. Of the 192 enrolled patients, 3 were excluded for protocol violations and 4 were excluded for history of chronic AF. Data from 185 patients from the original study were available for review. Sixty patients (32%) had new onset AF after cardiac surgery. There was no difference among groups in the incidence of AF (control group, 21%; steroid group, 41%; hemofiltration group, 36%; P = 0.057 among groups). The only risk factor for the development of AF was age (mean age of patients with AF, 65.4 +/- 10.1 yr vs patients without AF, 61.4 +/- 11.5 yr; P = 0.024). When age, procedure type, and presence or absence of chronic obstructive pulmonary disease were controlled for in multivariate analysis, the difference among study groups remained nonsignificant (P = 0.108). Perioperative corticosteroids or the use of hemofiltration during CPB did not decrease the incidence of AF after cardiac surgery. Further studies evaluating the efficacy and safety of perioperative corticosteroids for prevention of postoperative AF are warranted before their routine use can be recommended.

Association of IL6 and IL10 with renal dysfunction and the use of haemofiltration during cardiopulmonary bypass☆

Assessment of the effects of haemofiltration during cardiopulmonary bypass (CPB) in coronary artery bypass grafting (CABG) on the renal function and correlation with interleukin 6 (IL6) and interleukin 10 (IL10) levels. Seventy-nine patients scheduled for elective CABG were prospectively randomised into two groups. Group A with a haemofilter attached to arterial line of the CPB circuit and group B without a haemofilter. The two groups were comparable in their symptoms, sex, and previous history of myocardial infarction, left ventricular function, cross-clamp time, bypass time and total grafting per patients. Blood urea and creatinine levels were measured the day before operation, 12h after operation and on the 3rd postoperative day. IL6 and IL10 were measured in blood samples collected 1h before surgery, on arrival to ITU and after 12h. IL6 and IL10 levels were measured using ELISA test. High levels of IL6 (>100 pg/ml) postoperatively were associated with increased incidence of renal dysfunction (p<0.017). Additionally, high IL10 (>30 pg/ml) levels postoperatively were associated with increased incidence of renal dysfunction (p<0.014). There were no effects of the haemofilter on postoperative IL6 and IL10 levels. Use of haemofiltration during CPB was found not to be protective against renal dysfunction (p<0.071). Haemofilter use during cardiopulmonary bypass does not have a protective effect on postoperative kidney function. Haemofilter has no effect on the level of IL6 and IL10.

Hemofiltration for hyperbilirubinemia after left ventricular assist system implantation: Report of four cases

We hypothesized that the use of hemofiltration (HF) to reduce cytokines may attenuate the hyperbilirubinemia that often develops after left ventricular assist system (LVAS) implantation. Four patients with hyperbilirubinemia after LVAS implantation underwent HF continuously for 7 days. Blood samples were collected and the serum concentrations of total bilirubin (T-Bil), interleukin (IL)-6, and IL-8 were measured. We also measured the serum concentrations of IL-6 and IL-8 in the blood flowing into and out of the filter. Two patients had reduced serum concentrations of IL-6, IL-8, and T-Bil, but the other two did not, despite the effective filtration of these cytokines. Our findings suggest that the reduction of cytokines by HF may assist in the treatment of hyperbilirubinemia after LVAS placement in some patients.

Prevention and Treatment of Contrast-Induced Nephropathy

Contrast-induced nephropathy (CIN) is a well-known complication of therapeutic and diagnostic procedures requiring contrast administration and accounts for 10 to 12% of acute renal failure in hospitalized patients. Although the incidence of this complication is relatively low, its consequences can be catastrophic. The development of CIN is associated with increased hospital length of stay, an increased requirement for acute dialysis, and an increased risk of death. Preexisting renal dysfunction, age, diabetes, congestive heart failure, and volume of administered contrast are all associated with a risk of developing CIN. Despite a large number of clinical trials that have evaluated prophylaxis strategies for CIN, only the use of hemofiltration and N-acetylcysteine (NAC) in specific subgroups of patients have been shown to reduce dialysis requirement and mortality in patients undergoing angiographic procedures. In this review we will discuss the epidemiology and the risk factors for CIN and the evidence for commonly employed prophylaxis strategies, and we will provide general recommendations with respect to CIN prevention and management.

Pre-dilution on-line haemofiltration vs low-flux haemodialysis: a randomized prospective study

Accumulation of larger molecular weight uraemic toxins molecules may have a negative effect on the cardiovascular and nutritional state of dialysis patients and influence uraemic symptomatology. Their clearance can be enhanced by the use of haemofiltration (HF). The effects of low-flux haemodialysis (HD) (ultrapure dialysate; polyamide membranes) and pre-dilution on-line HF (1:1 blood/substitution ratio; target filtration volume: 1.2 times body weight) on cardiovascular and nutritional parameters, interdialytic levels of uraemic toxins and quality of life (QOL; Laupacis questionnaire) were assessed during 1 year follow-up. Forty patients were randomized. After 1 year, 27 patients were eligible for analysis (HF: 13 patients; HD: 14 patients). Left ventricular mass index did not change in the HF patients (127+/-33 --> 131+/-36 g/m(2) after 12 months) or in the HD group (135+/-34 --> 138+/-32 g/m(2)). Also, there were no changes in pulse wave velocity, and 48 h systolic and diastolic blood pressures. Lean body mass, assessed by dual-energy X-ray absorptiometry, increased in the HF group (44.8+/-8.9 --> 46.2+/-9.6 kg; P<0.05), but not in the HD group (49.4+/-9.2 --> 50.6+/-8.8 kg), although differences between groups were not significant. Insulin-like growth factor-1 levels remained stable in the HF patients, but decreased in the HD group (P<0.05 between groups). QOL for physical symptoms improved in the HF group (4.2+/-1.2 --> 5.0+/-1.1; P<0.05 within the HF group and P = 0.06 between groups), but not in the HD group (4.0+/-1.0 --> 4.4+/-1.4). beta2-microglobulin, complement factor D and homocysteine decreased significantly in the HF but not in the HD group, whereas l-ADMA, leptin and advanced glycation end-products-related fluorescence did not change. No changes in cardiovascular parameters were observed during pre-dilution on-line HF compared with low-flux HD. Treatment with on-line HF resulted in marked changes in the uraemic toxicity profile, an improvement in physical well-being and a small improvement in nutritional state.