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Despite wide interest in glycocalyx biomarkers, their values in healthy individuals, patients after abdominal surgery, and septic patients have been poorly understood. We searched MEDLINE, CENTRAL and EMBASE for papers measured glycocalyx biomarkers in healthy individuals, patients after abdominal surgery and septic patients. We extracted 3948 titles and identified 58 eligible papers. Syndecan 1 was the most frequently measured biomarker (48 studies). Its mean or median value in healthy individuals varied to a biologically implausible degree, from 0.3 to 58.5 ng/ml, according to assay manufacturer. In post-operative patients, syndecan 1 levels increased after pancreatic surgery or liver surgery, however, they showed minor changes after hysterectomy or laparoscopic surgery. In septic patients, biomarker levels were higher than in healthy volunteers when using the same assay. However, six healthy volunteer studies reported higher syndecan 1 values than after pancreatic surgery and 24 healthy volunteer studies reported higher syndecan 1 values than the lowest syndecan 1 value in sepsis. Similar findings applied to other glycocalyx biomarkers. Glycocalyx damage biomarkers values are essentially defined by syndecan 1. Syndecan 1 levels, however, are markedly affected by assay type and show biologically implausible values in normal, post-operative, or septic subjects. [ABSTRACT FROM AUTHOR]

Objective: To compare the characteristics, use of invasive ventilation and outcomes of patients admitted with critical asthma syndrome (CAS) to ICUs in Australia and New Zealand (ANZ), and a large cohort of ICUs in the United States (US). Methods: We examined two large databases of ICU for patients admitted with CAS in 2014 and 2015. We obtained, analyzed, and compared information on demographic and physiological characteristics, use of invasive mechanical ventilation, and clinical outcome and derived predictive models. Results: Overall, 2202 and 762 patients were admitted with a primary diagnosis of CAS in the ANZ and US databases respectively (0.73% vs. 0.46% of all ICU admissions, P < 0.001). A similar percentage of patients received invasive mechanical ventilation in the first 24 h (24.7% vs. 24.4%, P = 0.87) but ANZ patients had lower respiratory rates and higher PaCO2 levels. Overall mortality was low (1.23 for ANZ and 1.71 for USA; P = 0.36) and even among invasively ventilated patients (2.4% for ANZ vs. 1.1% for USA; P = 0.38). However, ANZ patients also had longer length of stay in ICU (43 vs. 37 h, P = 0.001) and hospital (105 vs. 78 h, P = 0.003). Conclusions: Patients admitted to ANZ and USA ICU with CAS are broadly similar and have a low and similar rate of invasive ventilation and mortality. However, ANZ patients made up a greater proportion of ICU patients and had longer ICU and hospital stays. These findings provide a modern invasive ventilation and mortality rates benchmark for future studies of CAS. [ABSTRACT FROM AUTHOR]

We present a case of a patient who ingested an isopropanol based hand sanitiser and developed severe CNS depression and cardiovascular collapse which was treated with continuous venovenous haemodiafiltration (CVVHDF) and angiotensin II. In a case of isopropanol poisoning where haemodialysis was undertaken, average clearance for isopropanol was 137 ml/min and was 165 ml/min for acetone [[3]]. Isopropyl alcohol poisoning treated with hemodialysis: kinetics of isopropyl alcohol and acetone removal. [Extracted from the article]

Novel acute kidney injury (AKI) biomarkers offer promise of earlier diagnosis and risk stratification, but have yet to find widespread clinical application. We measured urinary α and π glutathione S-transferases (α-GST and π-GST), urinary l-type fatty acid-binding protein ( l-FABP), urinary neutrophil gelatinase-associated lipocalin (NGAL), urinary hepcidin and serum cystatin c (CysC) before surgery, post-operatively and at 24 h after surgery in 93 high risk patient undergoing cardiopulmonary bypass (CPB) and assessed the ability of these biomarkers alone and in combination to predict RIFLE-R defined AKI in the first 5 post-operative days. Twenty-five patients developed AKI. π-GST (ROCAUC = 0.75), lower urine Hepcidin:Creatine ratio at 24 h (0.77), greater urine NGAL:Cr ratio post-op (0.73) and greater serum CysC at 24 h (0.72) best predicted AKI. Linear combinations with significant improvement in AUC were: Hepcidin:Cr 24 h + post-operative π-GST (AUC = 0.86, p = 0.01), Hepcidin:Cr 24 h + NGAL:Cr post-op (0.84, p = 0.03) and CysC 24 h + post-operative π-GST (0.83, p = 0.03), notably these significant biomarkers combinations all involved a tubular injury and a glomerular filtration biomarker. Despite statistical significance in receiver-operator characteristic (ROC) analysis, when assessed by ability to define patients to two groups at high and low risk of AKI, combinations failed to significantly improve classification of risk compared to the best single biomarkers. In an alternative approach using Classification and Regression Tree (CART) analysis a model involving NGAL:Cr measurement post-op followed by Hepcidin:Cr at 24 h was developed which identified high, intermediate and low risk groups for AKI. Regression tree analysis has the potential produce models with greater clinical utility than single combined scores. [ABSTRACT FROM AUTHOR]

Background: Terlipressin improves renal function in some patients with type-1 hepato-renal syndrome (HRS). Renal contrast-enhanced ultrasound (CEUS), a novel imaging modality, may help to predict terlipressin responsiveness. Objectives: We used CEUS to estimate the effect of terlipressin on the renal cortical microcirculation in type-1 HRS. Methods: We performed renal CEUS scans with destruction-replenishment sequences using Sonovue® (Bracco, Milano Italy) as a contrast agent at baseline and after the intravenous administration of 1 mg of terlipressin, in four patients with type-1 HRS. We analyzed video sequences offline using dedicated software. We derived a perfusion index (PI) at each time point for each patient. Results: Patients 1 and 2 had severe presentation and were admitted to the intensive care unit. Both showed a marked increase in PI (+216% and + 567% of baseline) in response to terlipressin. Patients 3 and 4 had less severe presentations and had a decrease in PI (−53% and −20% of baseline) in response to terlipressin. Patients 1, 2, and 4, but not patient 3, responded to terlipressin therapy with a decrease in serum creatinine to <150 µmol/L. Conclusions: CEUS detected changes in renal cortical microcirculation in response to terlipressin and demonstrated heterogeneous microvascular responses to terlipressin. These initial proof-of-concept findings justify future investigations. [ABSTRACT FROM AUTHOR]

Context: Cardiac surgery. Objective: To compare plasma and urinary neutrophil gelatinase-associated lipocalin (P-/U-NGAL) in on-pump ( n = 43) versus off-pump ( n = 40) surgery. Materials and methods: We obtained perioperative P-/U-NGAL and outcome data. Results: P-/U-NGAL increased after surgery. P-NGAL was higher post-surgery in on pump patients (139 versus 67 µg L−1; p < 0.001), but not at 24 h. There were no differences in U-NGAL. Correlation between P-/U-NGAL and plasma creatinine was weak. Discussion: P-NGAL acts like a neutrophil activation biomarker and U-NGAL like a tubular injury marker. Conclusion: On-pump patients had greater neutrophil activation. On- versus off-pump surgery had similar impact on tubular cells. [ABSTRACT FROM AUTHOR]

Background and aims: Hypercytokinemia is believed to be harmful and reducing cytokine levels is considered beneficial. Extracorporeal blood purification (EBP) techniques have been studied for the purpose of cytokine reduction. We aimed to study the efficacy of various EBP techniques for cytokine removal as defined by technical measures. Method: We conducted a systematic search for human clinical trials which focused on technical measures of cytokine removal by EBP techniques. We identified 41 articles and analyzed cytokine removal according to clearance (CL), sieving coefficient (SC), ultrafiltrate (UF) concentration and percentage removed. Results: We identified the following techniques for cytokine removal: standard hemofiltration, high volume hemofiltration (HVHF), high cut-off (HCO) hemofiltration, plasma filtration techniques, and adsorption techniques, ultrafiltration (UF) techniques relating to cardiopulmonary bypass (CPB), extracorporeal liver support systems and hybrid techniques including combined plasma filtration adsorption. Standard filtration techniques and UF techniques during CPB were generally poor at removing cytokines (median CL for interleukin 6 [IL-6]: 1.09 mL/min, TNF-alpha 0.74 mL/min). High cut-off techniques consistently offered moderate cytokine removal (median CL for IL-6: 26.5 mL/min, interleukin 1 receptor antagonist [IL-1RA]: 40.2 mL/min). Plasma filtration and extracorporeal liver support appear promising but data are few. Only one paper studied combined plasma filtration and adsorption and found low rates of removal. The clinical significance of the cytokine removal achieved with more efficacious techniques is unknown. Conclusion: Human clinical trials indicate that high cut-off hemofiltration techniques, and perhaps plasma filtration and extracorporeal liver support techniques are likely more efficient in removing cytokines than standard techniques. [ABSTRACT FROM AUTHOR]

Managing post-operative surgical patients can be complex, with many patients at risk of complications and mortality. We piloted a model for co-management of high risk surgical patients: the post-operative surveillance team (POST). We conducted a survey to test the proposition that POST would be popular with nurses and junior doctors. We conducted a questionnaire survey of nurses and doctors involved with the POST programme. Fifty-three nurses and 10 doctors responded to the survey: 60% response rate. Of 63 respondents: 62 (98%; 95% CI: 92-100%) agreed that POST was valuable, 61 (97%; 95% CI: 89-99%) agreed that POST should continue, and 61 (97%; 95% CI: 89-99%) agreed that they enjoyed working with POST. In open ended responses 39% commented that POST provided supervision, mentoring, education, or collaboration. We conclude that POST was popular with surgical ward nurses and doctors. This popularity is one factor supporting a permanent service. [ABSTRACT FROM AUTHOR]

Purpose: The choice of vascular access catheter may affect filter life during continuous renal replacement therapy (CRRT). In particular, differences in catheter design might affect the incidence of circuit clotting related to catheter malfunction. Design and setting: Sequential controlled study in a tertiary, adult intensive care unit (ICU). Aim: To compare circuit life when CRRT was performed with a Niagara™ catheter or a Medcomp™ catheter. Patients and measurements: We studied 46 patients with acute kidney injury requiring CRRT, all delivered with catheters in the femoral position. We obtained information on age, gender, disease severity score [acute physiology and chronic health evaluation (APACHE II) and APACHE III], filter life, heparin dose per hour, daily systemic hemoglobin concentration, platelet count, international normalized ratio (INR), and activated partial thromboplastin time (APTT) during CRRT. Results: We studied 254 circuits in 46 patients. Of these, 26 patients (140 circuits) used the Niagara catheter and 20 patients (114 circuits) used the Medcomp catheter. Median circuit life in the two groups were 11 h and 7.3 h, respectively ( p < 0.01). Patients using Medcomp catheters had a lower platelet count ( p = 0.04) and a lower hemoglobin concentration ( p = 0.01), but INR ( p = 0.16), APTT ( p = 0.46), anticoagulant treatment ( p = 0.89), and heparin dose per hour ( p = 0.24) were similar. After correcting for confounding variables by multivariable linear regression analysis, it was found that the choice of catheter is not an independent predictor of circuit life. On Kaplan-Meier survival analysis, circuit life was not significantly different between the two catheters ( p = 0.87). Conclusion: The choice of either the Niagara or Medcomp catheter does not appear to be a significant independent determinant of circuit life during CRRT. [ABSTRACT FROM AUTHOR]

Objective: To test the precision and limits of agreement of point-of-care testing (POCT)-based measurement of serum creatinine (Cr) in critically ill patients. Methods: We studied 250 paired blood samples from 82 critically ill patients from a general intensive care unit by simultaneous POCT and central laboratory testing (Jaffé method). Correlation, precision, bias, and limits of agreement were assessed. Possible confounders for interference of noncreatinine chromogens were evaluated by multivariate linear regression analysis. Results: The mean difference in serum Cr measured by central laboratory and POCT was ++9.6 μmol/L (95%% limits of agreement: −11.2 to ++30.4 μmol/L). The mean percentage difference between the two techniques was 8.7%% (95%% limits of agreement −7.8%% to ++25.1%%). On multivariate regression, the difference in serum Cr was increased with greater hemoglobin and lactate levels but decreased with greater bilirubin, albumin, and calcium levels. Conclusions: Compared with the central laboratory testing, POCT-based measurement of serum Cr in critically ill patients carried a small negative bias. This difference appeared affected by the blood levels of biochemical variables known to affect the Jaffé method. POCT-based Cr measurement appears sufficiently accurate for clinical use. [ABSTRACT FROM AUTHOR]

There is limited information on the incidence of acute kidney injury (AKI) in patients with traumatic brain injury (TBI) although AKI may contribute to morbidity and mortality. We investigated the incidence of AKI in patients with moderate and severe TBI and the association of AKI with risk factors and outcomes in these patients. We studied all TBI patients over 16 years of age admitted to the two designated trauma hospitals in the state of Victoria, Australia from 1 January to 31 December 2008. Patients were included if they had head trauma and presented with a Glasgow coma scale (GCS) <13. Prospectively collected data from the hospital trauma registries, ICUs, and pathology databases were analyzed retrospectively. Risk injury failure loss end (RIFLE) criteria were used to categorize renal function. The incidence of AKI was 9.2% (19/207). Patients who developed AKI were older, had higher severity of illness scores, and a lower GCS. Overall 42.1% of these patients died in hospital compared with 18.1% in patients without AKI. In univariable linear regression analysis, age, severity of illness, and admitting hospital were associated with AKI. After multivariable logistic regression, the occurrence of AKI was associated with age ( p < 0.001) and higher APACHE III scores ( p = 0.016). AKI is relatively common even in patients with TBI. Its association with age and APACHE III scores helps identify patients at higher risk of AKI. [ABSTRACT FROM AUTHOR]

During acute kidney injury (AKI), lowered glomerular filtration rate (GFR) is believed to be consequent to reduced renal plasma flow (RPF). We aimed to systematically evaluate the evidence for such an association. Using specific search terms, we systematically interrogated the Pub Med electronic reference database for studies of human AKI where renal plasma or blood flow and GFR were measured; older articles were then identified by screening bibliographies of retrieved reports. We identified 22 articles describing 250 patients (203 native kidney, 47 in renal allograft). Of these studies, 8 articles (110 patients) estimated effective renal plasma flow (ERPF) by clearance techniques and 14 articles (140 patients) estimated true renal plasma flow (TRPF). Mean RPF was 272 mL/min (95% CI 213–331) and GFR 13.9 mL/min (9.9–17.9). Mean TRPF was significantly greater than mean ERPF (344 vs. 180, p = 0.004) despite lower mean GFR (8.8 vs. 20.4, p = 0.002). There was no significant association between RPF and GFR between studies. Eleven studies presented individual patient data (76 patients: 49 TRPF, 27 ERPF); here, individual patient ERPF was associated with GFR ( r2 = 0.52), but TRPF was not. During AKI in man, there is only a limited association between ERPF and GFR, and no detectable association between TRPF and GFR. [ABSTRACT FROM AUTHOR]

Point of care technology makes it possible to measure blood and urine creatinine and electrolytes within the intensive care unit. We tested whether such point of care technology can accurately measure urine creatinine and electrolytes. We obtained urine from 28 patients for a total of 77 paired samples and measured creatinine and electrolytes using central laboratory technology and point of care technology. The mean difference in urine creatinine was 74 mcmol/L with 95% limits of agreement of −673 to 821 mcmol/L. The mean difference in urinary sodium was 0.282 mmol/L with 95% limits of agreement of −14 to 15 mmol/L. Significantly greater biases and wider limits of agreement were seen for potassium and chloride. We conclude that, despite the limited bias, due to wide limits of agreement, urinary creatinine and sodium cannot be estimated with point of care technology. Even greater inaccuracies make the estimation of potassium and chloride in urine by point of care technology not usable for clinical purposes. [ABSTRACT FROM AUTHOR]

Rationale. Few studies have evaluated the epidemiology of acute kidney injury (AKI) in trauma. Objective. To evaluate the incidence, risk factors, and outcomes associated with early AKI (evident within 24 hours of admission) in critically ill trauma patients. Methods. A retrospective interrogation of prospectively collected data from the Australian New Zealand Intensive Care Society Adult Patient Database. A total of 9,449 trauma patients were admitted for ≥24 hours to 57 intensive care units across Australia from January 1st, 2000, to December 31st, 2005. Main Findings. The crude incidence of AKI was 18.1% (n = 1,711). Older age, female sex (OR 1.60, 95% CI, 1.43-1.78, p < 0.0001), and the presence of co-morbid illness (OR 2.70, 95% CI 2.3-3.2, p < 0.0001) were associated with higher odds of AKI. Those with trauma not associated with brain injury (OR 2.40, 95% CI, 2.1-2.7, p < 0.0001) and a higher illness severity (OR 1.12, 95% CI, 1.11-1.12, p < 0.001) also had higher likelihood of AKI. Overall, AKI was associated with a higher crude mortality (16.7% vs. 7.8%, OR 2.36, 95% CI, 2.0-2.7, p < 0.001). Each RIFLE category of AKI was independently associated with hospital mortality in multi-variable analysis (risk: OR 1.69; injury OR 1.88; failure 2.29). Conclusions. Trauma admissions to ICU are frequently complicated by early AKI. Those at high risk for AKI appear to be older, female, with co-morbid illnesses, and present with greater illness severity. Early AKI in trauma is also independently associated with higher mortality. These data indicate a higher burden of AKI than previously described. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To compare the effect of lactate vs. bicarbonate-buffered replacement fluids on electrolyte mass balance during isovolemic continuous veno-venous hemofiltration (CVVH). DESIGN: Randomized controlled study with double cross over. SETTING: Intensive care unit of a tertiary university hospital. Patients and participants: Eight patients with acute renal failure (ARF). INTERVENTIONS: Isovolemic CVVH (2L/hr of replacement fluid) was performed in random order with either bicarbonate or lactate-buffered replacement fluid delivered pre-filter. Measurements and RESULTS: Sodium, potassium, chloride, magnesium, and phosphate, were measured in each sample. There was a mass gain of sodium, which was similar under both conditions (bicarbonate: 23.3 ± 4.9 mmol/hr, lactate: 22.7 ± 3.5 mmol/hr). Mass chloride gains occurred with bicarbonate-buffered replacement fluid only (12.8 ± 5.3 mmol/hr), while there was an overall net loss of chloride with lactate fluids (− 2.5 ± 5.2 mmol/hr), resulting in a significant difference in chloride mass balance (p < 0.0001). Magnesium mass balance was negative with bicarbonate buffer only (− 0.6 ± 0.2 mmol/hr) and also differed significantly from that obtained with lactate fluids (− 0.1 ± 0.2 mmol/hr, p < 0.0001). Phosphate losses (bicarbonate: − 1.7 ± 0.7 mmol/hr, lactate: − 1.7 ± 0.5 mmol/hr) were equivalent with both buffers. Potassium mass balance was neutral. CONCLUSIONS: Mass balance during isovolemic CVVH is significantly affected by the type of replacement fluid administered pre-filter. Isovolemic CVVH is not isonatremic and the use of bicarbonate-buffered fluid results in a significant accumulation of chloride and a loss of magnesium. [ABSTRACT FROM AUTHOR]

OBJECTIVES: To measure outflow and inflow hydraulic resistance in double-lumen catheters used for hemofiltration under standardized laboratory conditions. SETTING: ICU Laboratory of tertiary unit. METHODS: Heparinized spent red cells diluted in polygeline solution to a constant hematocrit of 32% at 37°C were pumped using a standard Prisma M60 circuit through several hemofiltration catheters. Blood pump speed was increased and decreased in steps of 30 mL/min (30, 60, 90, 120, 150, and 180 mL/min) and catheter outflow and inflow pressures recorded and used to define the pressure flow relationship (line of hydraulic resistance) for each. RESULTS: Double-lumen catheters posed different resistances to outflow or inflow. Among the <15 cm long catheters, the 11.5 Fr Quinton-Mahurkar (0.56 mmHg/mL/min) catheter offered the least resistance to outflow, while the Medcomp 11.5 Fr catheter offered the least resistance to inflow (0.78 mmHg/mL/min). Among the >19 cm long catheters, the 13.5 Fr Vascath Niagara catheter showed the lowest blood flow resistance to both outflow (0.63 mmHg/mL/min) and inflow (0.83 mmHg/mL/min). Longer catheters did not pose statistically greater resistance to both outflow and inflow. Resistance to inflow was consistently greater than resistance to outflow (p = 0.003). Overall, the Prisma M60 blood circuit alone accounted for 40% of the total extracorporeal circuit blood flow resistance. CONCLUSIONS: Proprietary hemofiltration catheters have variable resistance to blood flow under standard ex-vivo conditions. This ex-vivo information might be useful to clinicians in guiding their choice of catheters for clinical use. [ABSTRACT FROM AUTHOR]

Background and AIMS: The prevention of filter clotting is an important goal in the management of continuous renal replacement therapy (CRRT). Anticoagulation is the mainstay of such prevention. However, other strategies might prolong filter life without increasing the risk of bleeding. We tested the effectiveness of three strategies (use of flat plate configuration, heparin administration into the air chamber and use of a larger membrane surface) aimed at prolonging circuit life without increasing the dose of anticoagulation. METHODS: Thirty-one critically ill patients with acute renal failure (ARF) managed with continuous venovenous hemofiltration (CVVH) were studied. Filters were randomized in a crossover design to three consecutive studies: (1) filtration with either hollow-fiber or flat-plate hemofilters, (2) administration of heparin dose pre-filter or divided into pre-filter and directly into the bubble trap chamber and (3) use of two different surface areas with Filtral 8 (surface area 0.75 m2) vs. Filtral 12 (surface area 1.30 m2) hemofilters. RESULTS: Mean circuit life for flat-plate and hollow-fiber hemofilters (cohort 1) was 14.7 ± 4.7 h and 17.1 ± 2.8 h respectively (NS). Mean circuit life for single heparin administration site vs. double site administration (cohort 2) was 17 ± 3.2 h and 18 ± 3.1 h respectively (NS). Mean circuit lifespan for 0.75 m2 and 1.30 m2 hemofilters was 16 ± 12.2 h and 15.7 ± 14.3 h respectively (NS) (cohort 3). Visible clot formation in the bubble trap chamber was a frequent cause of circuit failure. CONCLUSION: Neither flat plate membrane configuration nor increasing membrane surface area, nor heparin administration in the air chamber prolong circuit life during CVVH. The bubble trap chamber is a frequent site of circuit clotting. [ABSTRACT FROM AUTHOR]

Background and OBJECTIVES: Different techniques of continuous renal replacement therapy (CRRT) might have different effects on azotemic control. Accordingly, we tested whether continuous veno-venous hemodiafiltration (CVVHDF) or continuous veno-venous hemofiltration (CVVH) would achieve better control of serum creatinine and plasma urea levels. DESIGN: Retrospective controlled study. SETTING: Two tertiary Intensive Care Units. Patients: Critically ill patients with acute renal failure (ARF) treated with CVVHDF (n = 49) or CVVH (n = 50). INTERVENTIONS: Retrieval of daily morning urea and creatinine values before and after the initiation of CRRT for up to 2 weeks of treatment. Measurements and RESULTS: Before treatment, serum urea and creatinine concentrations were significantly lower in the CVVH group than in CVVHDF group (urea: 31.0 ± 15.0 mmol/L for CVVHDF and 24.7 ± 16.1 mmol/L for CVVH, p = 0.01, creatinine: 547 ± 308 µmol/L vs. 326 ± 250 µmol/L, p < 0.0001). These differences were still significant after 48 h of treatment (urea: 20.1 ± 8.3 mmol/L vs. 14.1 ± 6.1 mmol/L; p = 0.0003, creatinine: 360 ± 189 µmol/L vs. 215 ± 118 µmol/L; p < 0.0001). Throughout the duration of therapy, mean urea levels (22.3 ± 9.0 mmol/L for CVVHDF vs. 16.7 ± 7.8 mmol/L for CVVH, p < 0.0001) and mean creatinine levels (302 ± 167 vs. 211 ± 103 µmol/L, p < 0.0001) were better controlled in the CVVH group. CONCLUSIONS: CRRT strategies based on different techniques might have a significantly different impact on azotemic control. [ABSTRACT FROM AUTHOR]

Background: Achieving “adequacy of dialysis” includes the maintenance of normal serum ionized calcium concentrations and is an important therapeutic goal in the treatment of acute renal failure (ARF). It is unknown whether this goal is best achieved with intermittent or continuous renal replacement therapy. METHODS: We compared the effects of continuous veno–venous hemodiafiltration (CVVHDF) and intermittent hemodialysis (IHD) on serum ionized calcium concentrations using daily morning blood tests in 88 consecutive intensive care patients of which half were treated with IHD and half with CRRT. RESULTS: Mean patient age was 54 ± 14 years for IHD and 60 ± 14 years for CVVHDF (NS). However, patients who received CVVHDF were significantly more critically ill (mean APACHE II scores: 24.4 ± 5.1 for IHD vs. 29.2 ± 5.7 for CVVHDF, p<0.003). Before treatment, the mean ionized calcium concentration was 1.177 ± 0.03 mmol/l for IHD and 1.172 ± 0.04 mmol/l for CVVHDF (NS), with abnormal values in 51.6% of IHD patients and in 68% of CVVHDF patients (NS). During treatment, hypocalcemia was significantly more common among CVVHDF patients (24.5% vs. 14.9%; p<0.011) while hypercalcemia was more frequent during IHD (36.1% vs. 25.6%; p<0.019). CONCLUSIONS: Abnormal serum ionized calcium concentrations are frequent in ARF patients before and during renal replacement. Once dialytic therapy is applied, CVVHDF is more likely to lower serum calcium concentrations, while IHD is more likely to induce hypercalcemia. Appreciation of these different biochemical effects may assist clinicians in adjusting dialytic therapy in selected patients. [ABSTRACT FROM AUTHOR]

Anticoagulants are commonly used to prolong circuit life during continuous hemofiltration. However, a clear correlation between routinely performed blood coagulability tests and circuit life has not been demonstrated. This lack of correlation may derive from the limited ability of such tests to describe the likelihood of in vivo clotting. We hypothesized that thromboelastography (TEG), which derives its variables from a closer reproduction of in vivo coagulation, would significantly correlate with filter life. Accordingly, we conducted a prospective pilot study of the correlation between filter life and TEG-derived variables in 21 hemofilters used in 6 critically ill patients admitted to a tertiary intensive care unit. It involved the performance of TEG during steady state anticoagulation, measurement of circuit life, and of routine coagulation variables. The results showed that the mean circuit life was 20.7 ± 4.0 h despite an average aPTT of 67.7 ± 12.8 s and a mean heparin dose of 472.5 ± 96.2 IU / h. The mean INR was 1.4 ± 1 and the mean platelet count was 118 ± 16 × 103 / mm3. Although several TEG variables correlated with heparin dose (p < 0.03), no correlation was found between any of the routine coagulation variables or any of the TEG variables and circuit life. In conclusion, no significant correlation between TEG derived variables or routinely measured coagulation variables and circuit life could be demonstrated. These findings suggest that such tests are not useful indicators of circuit anticoagulation adequacy and that factors other than blood coagulability may play a role in circuit failure. [ABSTRACT FROM AUTHOR]