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Biomedical subjects

W H Hartl

Publications and source records attributed to W H Hartl.

At least 37 records · Page 2Linked to original sources
PubMed1997

Tumor necrosis factor measurement and use of different anticoagulants: possible interference in plasma samples and supernatants from endotoxin-stimulated monocytes.

OBJECTIVE AND DESIGN: Unfractionated heparin is frequently used as an anticoagulant during blood sampling and in cell culture experiments. In the present study we investigated whether heparin and other anticoagulants (citrate and EDTA) interfered with measurements of plasma tumor necrosis factor alpha (TNF alpha) concentrations or with TNF alpha release from endotoxin-stimulated monocytes. MATERIAL AND METHODS: TNF alpha was measured by a WEHI 164 bioassay in the plasma of 16 septic patients anticoagulated with heparin, citrate, or EDTA. Anticoagulants were incubated with the bioassay cell line and cell lysis was monitored. To exclude falsely low TNF alpha concentrations, anticoagulants were incubated in increasing amounts with human recombinant TNF alpha/saline solution, and rTNF alpha recovery was measured either with the WEHI 164 bioassay or an ELISA test. Further, anticoagulants were incubated with monocytes isolated from healthy volunteers and stimulated with endotoxin. Supernatants were analyzed for TNF alpha with both test systems. RESULTS: No biologically active TNF alpha was detected in the plasma with heparin anticoagulation, whereas with citrate, reproducible, TNF alpha-induced cytotoxicity was detectable in blood samples of 13 of the 16 patients. Anticoagulation with EDTA resulted in fairly high, variable and poorly reproducible TNF alpha values. Only EDTA produced falsely high values by unspecific lysis of WEHI cells. Only heparin at a concentration of 20 I.U./ml or more was found to produce falsely low values by interaction with the TNF alpha bioassay, but also with the ELISA test. In monocyte culture experiments, heparin significantly attenuated the stimulatory effect of endotoxin on TNF alpha release already at the lowest concentration tested (25 I.U./ml). CONCLUSIONS: Heparin and EDTA may have significant adverse effects on TNF alpha measurement when used for blood sampling. Citrate does not interfere with the TNF alpha bioassay or ELISA, and seems, therefore, to be the anticoagulant of choice. Due to intrinsic interactions with various cell systems (including the WEHI cell and monocytes), one should be careful in using heparin in cell culture studies in which effects of TNF alpha or of endotoxin are being studied.

Anticoagulants↗
PubMed1997

Antithrombin III supplementation in severe sepsis: beneficial effects on organ dysfunction.

Activation of thrombin and of the coagulation system plays an important role in the pathophysiology of sepsis-associated organ dysfunction. Antithrombin III (AT III) is a natural inhibitor of thrombin, a central procoagulatory factor with pleiotropic activities. Experimental supplementation of AT III improved coagulation parameters and ameliorated organ dysfunction. To determine whether long-term AT III supplementation has beneficial effects on organ function, we conducted a randomized, prospective study in surgical patients with severe sepsis. The study evaluated the long-term effect of AT III supplementation (duration of treatment: 14 days). After randomization (AT III vs. control group), AT III was infused continuously over 14 days to obtain plasma AT III activities > 120%. Forty consecutive patients were recruited (20 AT III/20 control group). Eleven patients had a rapid fatal course and did not met the criterion of a 14 day treatment period. From these 11 patients, 8 patients (5 AT III/3 control group) died within 72 h due to septic shock. The remaining 14 AT III patients and 15 controls survived 14 days and showed no differences in baseline parameters of organ function. AT III caused a disappearance of disseminated intravascular coagulation (DIC) in all patients with DIC, whereas in control patients, the frequency of DIC remained constant (p < .05). In AT III patients a progressive increase in oxygenation index (PaO2/FiO2 ratio) and a continuous decrease in pulmonary hypertension index (mean pulmonary artery pressure/mean arterial pressure (PAP/MAP) ratio) indicated an improvement of lung function (p < .05 vs. control). AT III prevented the continuous rise in total serum bilirubin concentration observed in control patients and diminished the frequency of artificial renal support therapy (p < .05). Long-term supplementation with AT III may improve lung function and prevent the development of septic liver and kidney failure in patients with severe sepsis.

Adult↗
PubMed1997

Determination of protein synthesis in human rectal cancer in situ by continuous [1-13C]leucine infusion.

Previous studies on human colorectal tumor protein synthesis in situ relied on techniques that required intra- or perioperative sampling to obtain a sufficient biopsy size. The purpose of the present study was to develop a new technique by use of new mass spectrometry equipment [capillary gas chromatography (GC)-combustion isotope ratio mass spectrometry (IRMS)], which allows reduction of the necessary sampling size. Thereby, tumor sampling could be done via conventional rectosigmoidoscopy, excluding the need for further disturbing invasive measures. Fifteen postabsorptive patients with localized rectal cancer received a primed-constant infusion of [1-13C]leucine (0.16 mumol.kg-1.min-1 constant, 9.6 mumol/kg prime). Forceps biopsies were taken after 3 and 6 h. In five subjects, tumor tissue and normal mucosa were studied simultaneously. Determination of protein-bound leucine enrichment was done by GC-IRMS, and GC-quadrupole MS was used to determine tracer-to-tracee ratios (tracer/tracee) for free intracellular leucine. GC-MS data demonstrated achievement of a steady state in the precursor pool enrichment after 3 h of isotope infusion (tracer/tracee at 3 h: 6.34 +/- 0.46%, at 6 h: 6.58 +/- 0.38%). Calculation of tumor protein synthesis yielded a fractional synthetic rate (FSR) of 1.06 +/- 0.11%/h or 25.5 +/- 2.6%/day (range 12.0-37.1%/day). At any time, protein-bound leucine enrichment was significantly higher in tumor tissue than in normal mucosa of the same subject. However, protein synthetic rates were comparable (tumor: 1.09 +/- 0.20%/h, mucosa: 1.29 +/- 0.28%/h). Thus combined GC-combustion IRMS and GC-/quadrupole MS provide a simple, reliable, and minimally invasive method to determine tumor FSR in situ, thereby excluding interferences common to previous methods. Tumor and mucosa tissues are similar with respect to protein synthesis, but they apparently differ with respect to leucine extraction from the arterial blood.

Aged↗
PubMed1996

Effect of hemofiltration on hemodynamics and systemic concentrations of anaphylatoxins and cytokines in human sepsis.

OBJECTIVE: To determine whether hemofiltration (HF) can eliminate cytokines and complement components and alter systemic hemodynamics in patients with severe sepsis. DESIGN: Prospective observation study. SETTING: Surgical intensive care unit of a university hospital. PATIENTS: 16 patients with severe sepsis. INTERVENTIONS: Continuous zero-balanced HF without dialysis (ultrafiltrate rate 2 l/h) was performed in addition to pulmonary artery catheterization, arterial cannulation, and standard intensive care treatment. MEASUREMENTS AND MAIN RESULTS: Plasma and ultrafiltrate concentrations of cytokines (the interleukins IL-1 beta, IL-6, IL-8, and tumor necrosis factor alpha) and of complement components (C3adesArg, C5adesArg) were measured after starting HF (t0) and 4 h (t4) and 12 h later (t12). Hemodynamic variables including mean arterial pressure (MAP), mean central venous pressure, mean pulmonary artery pressure, pulmonary capillary wedge pressure, and cardiac output were serially determined. During HF, cytokine plasma concentrations remained constant. However, C3adesArg and C5adesArg plasma concentrations showed a significant decline during 12-h HF (C3adesArg: t0 = 676.9 +/- 99.7 ng/ml vs t12 = 467.8 +/- 71, p < 0.01; C5adesArg: 26.6 +/- 4.7 ng/ml vs 17.6 +/- 6.2, p < 0.01). HF resulted in a significant increase over time in systemic vascular resistance (SVR) and MAP (SVR at t0: 669 +/- 85 dyne.s/cm5 vs SVR at t12: 864 +/- 75, p < 0.01; MAP at t0: 69.9 +/- 3.5 mmHg vs MAP at t12: 82.2 +/- 3.7, p < 0.01). CONCLUSIONS: HF effectively eliminated the anaphylatoxins C3adesArg and C5adesArg during sepsis. There was also a significant rise in SVR and MAP during high volume HF. Therefore, HF may represent a new modality for removal of anaphylatoxins and may, thereby, deserve clinical testing in patients with severe sepsis.

Adult↗
PubMed1995

Thoracoscopic repair of thoracic spine trauma.

Modern concepts of treating thoracic and lumbar spinal trauma are based on posterior transpedicular fixation techniques which confer angular stability and instrument only a few levels of the spine. In addition, to prevent secondary losses in postoperative reduction of kyphotic deformities, transpedicular resection of torn discs, and inter- and intracorporeal bone grafting are included in the repair procedures for the entire damaged motion segment. However, due to the small size of the pedicles, a transpedicular approach to the injured vertebral body is not possible in the upper thoracic spine. Patients whose thoracic spine trauma is not serious enough to require ventral instrumentation through open thoracotomy, but who present with an unstable vertebral fracture, may profit from additional ventral bone grafting to stabilize the fracture. The present study examined the feasibility of thoracoscopic ventral bone grafting in seven patients with unstable fractures of the upper thoracic spine. For primary repair, we stabilized the fracture by using posterior transpedicular screw systems (rods or plates). Simultaneously, spongiosa was harvested from the posterior iliac crest and deepfrozen. Repair was completed a few days later via a ventral thoracoscopic approach. The main location of the ventral osseous defect was identified by intraoperative radiology. After mechanical removal of destroyed connective tissue and disc material, fusion was performed using the previously harvested spongiosa, which was placed into the intervertebral disc space and the anterior osseous defect. Our results show thoracoscopic bone grafting to be technically possible and associated with low morbidity, with a potential of yielding satisfactory long-term results.

Adult↗
PubMed1995

Hemofiltration in human sepsis: evidence for elimination of immunomodulatory substances.

Continuous hemofiltration is widely used for renal replacement therapy in patients with acute renal failure. It has been suggested that hemofiltration may also eliminate toxic mediators thought to be important in the pathophysiology of sepsis. The present study examined whether hemofiltration can activate or eliminate inflammatory mediators in patients with sepsis, and whether ultrafiltrate can alter specific functions of peripheral blood mononuclear leukocytes (PBMC) in vitro. Veno-venous hemofiltration was performed in 16 patients and in 5 healthy volunteers. Pre-filter (afferent), post-filter (efferent) and ultrafiltrate concentrations of cytokines (IL-1 beta, IL-6, IL-8, TNF alpha) and of complement components (C3, C3adesArg, C5adesArg, terminal complement complex) were measured after the beginning of hemofiltration (t0), and 60 minutes later (t60). PBMC, and monocyte and lymphocyte subfractions were incubated with ultrafiltrate, and cytokines were determined in the supernatants. Hemofiltration did not induce significant mediator activation. There was no evidence for significant cytokine elimination. However, pre-filter C3adesArg concentration showed a significant decline during hemofiltration (patients: t0 = 676.9 +/- 99.7 ng/ml, t60 = 545.4 +/- 83.2, P < 0.001; volunteers: t0 = 54.8 +/- 13.3 ng/ml, t60 = 33.9 +/- 10.7, P < 0.001). Ultrafiltrate from septic patients significantly stimulated PBMC and monocyte TNF alpha release, but suppressed lymphocyte IL-2 and IL-6 production. Ultrafiltrate from volunteers was without effect. Hemofiltration effectively eliminates certain mediators such as C3adesArg. Ultrafiltrate contains compounds with significant immunomodulatory qualities. Therefore, hemofiltration may represent a new modality for removal of immunomodulatory mediators.

Adjuvants, Immunologic↗
PubMed1995

Application of transcranial Doppler sonography to evaluate cerebral hemodynamics in carotid artery disease. Comparative analysis of different hemodynamic variables.

BACKGROUND AND PURPOSE: Transcranial Doppler sonography in combination with manipulation of cerebral resistance vessels is widely used to screen patients with suspected intracranial hemodynamic disturbances. Maximal flow velocity (Vmax), mean flow velocity (Vmean), cerebral pulsatility index (CPi), and cerebral resistance index (CRi) have all been used to describe cerebral hemodynamics. The present study examined CO2 reactivity of the above hemodynamic variables with respect to its variability between different age groups and its capability to discriminate between normal and abnormal findings. METHODS: Absolute and relative CO2 reactivity of Vmax, Vmean, CRi, and CPi were determined in both hemispheres in 30 young and 37 elderly control subjects and in 245 consecutive patients with strictly unilateral symptomatic (n = 101) or asymptomatic (n = 144) carotid artery disease (> 80% stenosis or occlusion). RESULTS: Hemispheric reactivities of Vmean, CRi, and CPi were significantly age dependent. Hemispheric Vmax reactivity and interhemispheric differences of individual reactivities (except absolute CPi reactivity) did not vary with age and could therefore be used to define normal values. Patient classification according to these values revealed different frequencies of subjects with pathological findings (3% for hemispheric Vmax reactivity, 5% to 7% for interhemispheric differences of Vmax or Vmean reactivity, 39% and 45% for interhemispheric differences of relative CRi and CPi reactivity, respectively). CONCLUSIONS: Hemispheric reactivities are less suitable to evaluate cerebral hemodynamics than interhemispheric differences, since most of the latter do not vary with age. However, interhemispheric differences vary with respect to their discriminatory power. Power is low for interhemispheric differences of Vmax and Vmean reactivity, since the corresponding frequencies of abnormal findings do not differ from the 5% frequency expected in the reference population (reference range defined as mean +/- 2 SD). With respect to the discriminatory power, interhemispheric differences of relative CRi and CPi reactivity may be superior to other parameters.

Adult↗
PubMed1994

Effect of carotid endarterectomy on patterns of cerebrovascular reactivity in patients with unilateral carotid artery stenosis.

BACKGROUND AND PURPOSE: Patients with unilateral significant carotid artery stenosis present with a variable intracranial hemodynamic status. In the majority of patients, hemodynamics are normal because of sufficient collateral flow. One subgroup shows poor ipsilateral hemodynamics because of a severely reduced blood supply, whereas in another subgroup of patients a steal phenomenon from the contralateral to the ipsilateral hemisphere can be observed during pharmacological provocation. The present study examined the effect of carotid endarterectomy (CEA) on these patterns of cerebrovascular hemodynamics in patients with carotid artery stenosis. METHODS: The CO2 reactivity of the cerebral resistance index (CRi) was determined with transcranial Doppler sonography in 63 patients with unilateral high-grade to threadlike carotid artery stenosis before and 3 months after CEA and in 37 control subjects. The interhemispheric asymmetry of CRi reactivity of the control group was used to differentiate between normal and abnormal findings. RESULTS: In patients with normal CRi asymmetry (comparable CRi reactivities at both hemispheres, n = 41), CEA did not change hemispheric CRi reactivity. In patients in whom CRi reactivity was absent at the contralateral hemisphere (intracerebral steal during hypercapnia, n = 12), CEA abolished the steal phenomenon by significantly increasing CRi reactivity at the contralateral hemisphere (preoperative, -1.0 +/- 2.1 %CRi/vol%CO2; postoperative, 5.2 +/- 0.7 %CRi/vol%CO2; P < .01). Patients who showed severely diminished ipsilateral CRi reactivity, compatible with a significantly reduced perfusion pressure at the poststenotic hemisphere (n = 10), demonstrated an improvement of ipsilateral CRi reactivity after surgery (preoperative, 0.6 +/- 0.8 %CRi/vol%CO2; postoperative, 3.7 +/- 1.1 %CRi/vol%CO2; P < .01). CONCLUSIONS: Most patients do not respond significantly to CEA. One small subgroup of patients who presented with severely disturbed ipsilateral hemodynamics demonstrated postoperative improvement at the poststenotic hemisphere, whereas in another small subgroup, who showed a steal phenomenon at the contralateral hemisphere, CEA improved contralateral hemodynamics. Determination of preoperative CRi reactivity allowed precise prediction of the effect of CEA on intracerebral hemodynamics.

Aged↗
PubMed1994

Patterns of cerebrovascular reactivity in patients with unilateral asymptomatic carotid artery stenosis.

BACKGROUND AND PURPOSE: Intracranial hemodynamic status varies in patients with unilateral significant carotid artery stenosis. It ranges from normal, because of sufficient collaterals, to poor, because of a severely reduced blood supply that puts the patient at an increased risk of stroke or cerebral ischemia. The present study examined patterns of abnormal cerebrovascular hemodynamics in patients with asymptomatic carotid artery stenosis. METHODS: The CO2 reactivity of the cerebral resistance index (CRi) and of mean blood flow velocity (vmean) was determined via transcranial Doppler sonography in 91 patients with unilateral high-grade to threadlike carotid artery stenosis and in 37 control subjects. The interhemispheric asymmetry of CRi reactivity of the control group was used to differentiate between normal and abnormal findings. RESULTS: We found that 64.8% of the patients demonstrated normal CRi asymmetry with comparable CRi reactivity (ipsilateral, 4.42 +/- 0.44 %CRi/vol%CO2; contralateral, 4.51 +/- 0.39 %CRi/vol%CO2) and vmean reactivity (ipsilateral, 0.080 +/- 0.004 m/s per vol%CO2; contralateral, 0.079 +/- 0.005 m/s per vol%CO2) at both hemispheres. In 16.5% of the patients, CRi reactivity was supranormal at the affected hemisphere. This phenomenon was due to an exaggerated dilatory response of the ipsilateral hemisphere and was combined with an absent CRi reactivity of the contralateral hemisphere (ipsilateral, 6.63 +/- 1.03 %CRi/vol%CO2; contralateral, -1.16 +/- 1.78 %CRi/vol%CO2). In contrast, hemispheric vmean reactivities were comparable (ipsilateral, 0.078 +/- 0.008 m/s per vol%CO2; contralateral, 0.077 +/- 0.008 m/s per vol%CO2). The remaining 18.7% showed severely diminished ipsilateral CRi reactivity (ipsilateral, 1.91 +/- 0.83 %CRi/vol%CO2; contralateral, 8.48 +/- 1.00 %CRi/vol%CO2) and vmean reactivity (ipsilateral, 0.073 +/- 0.007 m/s per vol%CO2; contralateral, 0.108 +/- 0.012 m/s per vol%CO2; P < .01), compatible with a significantly reduced perfusion pressure at the poststenotic hemisphere. CONCLUSIONS: Most asymptomatic patients do not suffer from severely abnormal hemodynamics at the poststenotic hemisphere. One small subgroup of patients presented with severely disturbed ipsilateral hemodynamics; another small subgroup demonstrated a steal phenomenon with secondary dilation of large cerebral vessels at the contralateral hemisphere. These subgroups require specific evaluation of proper treatment.

Aged↗
PubMed1994

[Immune mechanisms of post-traumatic hyperinflammation and sepsis].

Major trauma and consecutively associated infectious complications have a major impact on the mechanisms of the specific immune response and the nonspecific inflammatory reaction. The trauma-induced host defense abnormalities become strikingly evident with the analysis of cytokine synthesis patterns. The dissociation of cell-mediated immune responses following trauma is based upon an overrepresentation of suppressor-active monocytes and inadequate T-cell help in parallel. Corresponding dysregulation of cytokine production appears within many facets. Complement, endotoxin and antigen antibody complexes cause a massive activation of monocytes with an abnormal release of essential mediators, like PGE2, IL-1, IL-6, IL-8, TGF-beta and TNF-alpha. The regulation of cytokine synthesis under stressful conditions is differentially regulated for the individual mediators, either on a transcriptional or a posttranscriptional level. In our opinion, the endogenous provisions of the organism for survival following major injury are inadequate and from this hypothesis we derive the necessity for a substantial exogenous therapeutic intervention. The primary target of modern immunotherapy must be to inhibit the conversion of a systemic inflammatory reaction in immunocompromised patients towards a status of bacterial sepsis. Different approaches appear to be feasible to avoid the development of late multiorgan failure. These interventions have to be utilized preventively in a controlled manner as early as possible after trauma has occurred, and they must effectively protect different cell systems (lymphocytes, monocytes, PMNs and endothelial cells).

Colony-Stimulating Factors↗
PubMed1994

Iliac-subclavian-internal carotid artery bypass for cerebral ischemia due to multiple proximal supra-aortic vessel obstruction (aortic arch syndrome).

Severe cerebral ischemia was successfully treated in a patient with arteriosclerotic aortic arch syndrome by an iliac-subclavian-internal carotid artery bypass, using an extra-anatomic modified Dacron prosthesis externally coated with collagen. The procedure and material seem suitable for managing high-risk patients who have critically stenotic or occluded branches of the aortic arch and who would not tolerate anatomic, transthoracic repair.

Anastomosis, Surgical↗
PubMed1994

[Post-aggression metabolism: attempt at a status determination].

OBJECTIVE: Selection of important results in pathophysiology and pathobiochemistry of the surgical patient. SOURCES: Anglo-American and German literature since 1988. SELECTION CRITERIA: Importance of reported results for the understanding of superior interactions. RESULTS: The term 'postaggression' syndrome was introduced on the basis of earlier observations regarding the pathophysiology of the surgical patient. More recent results which addressed pathobiochemistry, and which had been obtained by methods of molecular biology, led to the new definition as systemic inflammatory response syndrome (SIRS). Knowledge on metabolic changes which are associated with SIRS increased significantly in the field of protein and carbohydrate metabolism. Concerning the clinically important phenomenon of protein catabolism, it is possible today to differentiate between changes in protein synthesis and protein degradation. The time period which had passed since the underlying trauma and the variable responses of different organ systems were recognized as important variables of catabolism. The ongoing question regarding possible mediators of protein catabolism still remains unanswered. Release of cytokines which can be observed in SIRS appears to play only an indirect role. The small bowel, which is important for the general pathophysiology of SIRS, gained a central position in amino acid metabolism (especially glutamine metabolism). A new aspect of carbohydrate metabolism was found in the liver. The accelerated cycling of glucose molecules between glucose, glucose-6-phosphate, and glucose (glucose cycling) seems to contribute to the increased energy expenditure found in SIRS. CONCLUSIONS: Use of new methods in in vivo and in vitro research significantly expanded the knowledge on pathophysiological and pathobiochemical mechanisms in SIRS. Future research activities should tie together these individual mechanisms into the complex network as it presents to the physician during clinical routine.

Acute-Phase Reaction↗
PubMed1993

[Transcranial Doppler sonography and cerebrovascular reserve capacity].

Measurements of blood flow velocity in the basal cerebral arteries during functional testing by means of transcranial Doppler sonography are reviewed. Special emphasis is placed on cerebrovascular reserve capacity, which we determined in two groups of patients with obstructive cerebrovascular disease and in normal persons. We discuss the value of functional testing during endovascular neuroradiological procedures.

Cerebrovascular Circulation↗
PubMed1992

Pathophysiology of unilateral high-grade carotid artery stenosis: evaluation of intracranial haemodynamics by analysis of velocity waveforms from the middle cerebral artery.

1. Transcranial flow velocity waves were measured via Doppler sonography of the middle cerebral artery during hypo-, hyper- and normo-capnia. Applying the principle of vascular impedance, flow velocity waves were analysed in 30 young subjects, 37 elderly subjects and 18 patients with high-grade unilateral internal carotid artery disease. 2. There was evidence that the relative peak-to-peak velocity in the middle cerebral artery could serve as an index of peripheral wave reflection and cerebral resistance (CRi). The response of CRi to changes in arterial CO2 concentration (CRi reactivity) showed a clear age-dependency. However, the absolute side-to-side asymmetry of CRi reactivity (delta R) did not vary with age and could be used to define a normal range (0-4%CRi/vol.%CO2). 3. Selective angiography demonstrated no cerebral cross-flow through the anterior part of the circle of Willis in nine patients with carotid artery stenosis whose absolute delta R was above the normal range and whose CRi reactivity of the affected hemisphere was lower than that of the healthy opposite hemisphere. Conversely, another group of nine patients, whose ipsilateral CRi reactivity was higher than the contralateral CRi reactivity, demonstrated cross-flow through the anterior part of the circle of Willis. 4. delta R may be used to identify patients who have high-grade internal carotid artery stenosis and present with low cerebral vascular resistance owing to poor intracerebral collaterals.

Adult↗
PubMed1991

Comparison of pump-driven and spontaneous continuous haemofiltration in postoperative acute renal failure.

In a comparison of spontaneous continuous arteriovenous haemofiltration (CAVH) and pump-driven haemofiltration (PDHF) for acute renal failure after surgery, 116 patients admitted to a surgical intensive care unit were assigned CAVH (48) or PDHF (68). The method of assignment was that a patient was treated by PDHF if he or she was the only patient requiring treatment at that time (only one pump was available); any other patient coming to the unit would be treated by CAVH. The groups were slightly unbalanced because there were fewer simultaneous cases than expected. The main endpoints were survival rate, control of uraemia, and additional application of haemodialysis. There were no differences between the patient groups in age, duration of treatment, severity of illness, serum creatinine concentration at the start of treatment, or cause of acute renal failure. Both treatments adequately controlled uraemia and fluid overload. However, the survival rate was significantly higher with PDHF than with CAVH (6 [12.5%] vs 20 [29.4%]; p less than 0.05). The daily ultrafiltrate volume was significantly higher with PDHF than with CAVH (15.7 [95% confidence interval 13.6-17.8] vs 7.0 [6.6-7.4] l/day; p less than 0.05). The volume of ultrafiltrate in patients with ischaemic or sepsis-induced acute renal failure was correlated with the survival rate. This finding suggests that the better survival rate in the PDHF group was due to faster elimination of toxic mediators (of molecular weight 800-1000 daltons) through the filter membrane by high-volume haemofiltration.

Acute Kidney Injury↗