Fluid management in acute kidney injury: from evaluating fluid responsiveness towards assessment of fluid tolerance

Despite the widespread use of intravenous fluids in acute kidney injury (AKI), solid evidence is lacking. Intravenous fluids mainly improve AKI due to true hypovolaemia, which is difficult to discern at the bedside unless it is very pronounced. Empiric fluid resuscitation triggered only by elevated serum creatinine levels or oliguria is frequently misguided, especially in the presence of fluid intolerance syndromes such as increased extravascular lung water, capillary leak, intra-abdominal hypertension, and systemic venous congestion. While fluid responsiveness tests clearly identify patients who will not benefit from fluid administration (i.e. those without an increase in cardiac output), the presence of fluid responsiveness does not guarantee that fluid therapy is indicated or even safe. This review calls for more attention to the concept of fluid tolerance, incorporating it into a practical algorithm with systematic venous Doppler ultrasonography assessment to use at the bedside, thereby lowering the risk of detrimental kidney congestion in AKI.

Factors affecting serum concentration of vancomycin in critically ill oliguric pediatric patients receiving continuous venovenous hemodiafiltration

Vancomycin is known to be unintentionally eliminated by continuous renal replacement therapy, and the protein bound fraction of vancomycin is also known to be different in adults and children. However, there are only a few studies investigating the relationship between the dose of continuous venovenous hemodiafiltration (CVVHDF) parameters and serum concentration of vancomycin in pediatric patients. The aim of this study was to determine clinical and demographic parameters that significantly affect serum vancomycin concentrations. This retrospective cohort study was conducted at a pediatric intensive care unit in a tertiary university children’s hospital. Data from oliguric patients who underwent CVVHDF and vancomycin therapeutic drug monitoring were collected. The correlation between factors affecting serum concentration of vancomycin was analyzed using mixed effect model. A total of 177 serum samples undergoing vancomycin therapeutic drug monitoring were analyzed. The median age of study participants was 2.23 (interquartile range, 0.3–11.84) years, and 126 (71.19%) were male patients. Serum concentration of vancomycin decreased significantly as the effluent flow rate (EFR; P < 0.001), dialysate flow rate (DFR; P = 0.009), replacement fluid flow rate (RFFR; P = 0.008), the proportion of RFFR in the sum of DFR and RFFR (P = 0.025), and residual urine output increased. The adjusted R² of the multivariate regression model was 0.874 (P < 0.001) and the equation was as follows: Vancomycin trough level (mg/L) = (0.283 × daily dose of vancomycin [mg/kg/d]) + (365.139 / EFR [mL/h/kg])–(15.842 × residual urine output [mL/h/kg]). This study demonstrated that the serum concentration of vancomycin was associated with EFR, DFR, RFFR, the proportion of RFFR, and residual urine output in oliguric pediatric patients receiving CVVHDF.

Improving the Clinical Skills Performance of Graduating Medical Students Using "WISE OnCall," a Multimedia Educational Module

INTRODUCTION

"Transitions to residency" programs are designed to maximize quality and safety of patient care, as medical students become residents. However, best instructional or readiness assessment practices are not yet established. We sought to study the impact of a screen-based interactive curriculum designed to prepare interns to address common clinical coverage issues (WISE OnCall) on the clinical skills demonstrated in simulation and hypothesize that performance would improve after completing the module.

METHODS

Senior medical students were recruited to participate in this single group prestudy/poststudy. Students responded to a call from a standardized nurse (SN) and assessed a standardized patient (SP) with low urine output, interacted with a 45-minute WISE OnCall module on the assessment and management of oliguria, and then evaluated a different SP with low urine output of a different underlying cause. Standardized patients assessed clinical skills with a 37-item, behaviorally anchored checklist measuring clinical skills (intraclass correlation coefficient [ICC], 0.55-0.81). Standardized nurses rated care quality and safety and collaboration and interprofessional communication using a 33-item literature-based, anchored checklist (ICC, 0.47-0.52). Standardized patient and SN ratings of the same student performance were correlated (r, 0.37-0.62; P < 0.01). Physicians assessed clinical reasoning quality based on the students' patient encounter note (ICC, 0.55-0.68), ratings that did not correlate with SP and SN ratings. We compared pre-post clinical skills performance and clinical reasoning. Fifty-two medical students (31%) completed this institutional review board -approved study.

RESULTS

Performance as measured by the SPs, SNs, and the postencounter note all showed improvement with mostly moderate to large effect sizes (range of Cohen's d, 0.30-1.88; P < 0.05) after completion of the online module. Unexpectedly, professionalism as rated by the SP was poorer after the module (Cohen's d, -0.93; P = 0.000).

DISCUSSION

A brief computer-based educational intervention significantly improved graduating medical students' clinical skills needed to be ready for residency.

Acute Stylet Peritoneal Dialysis in Acute Kidney Injury: The Soul Never Dies

BACKGROUND

Acute Kidney Injury (AKI) has a significant mortality rate. In developing countries, mortality due to AKI is high due to lack of access to dialysis facilities and related cost. The main goal of International Society of Nephrology (ISN) 0 by 25 initiative is to eliminate deaths due to AKI. Peritoneal dialysis is an underutilized modality in such a scenario. The aim of this study was to look into effectiveness of starting Acute stylet Peritoneal Dialysis (PD) in a resource constraint settings.

METHODS

In this prospective study conducted over a year, patients with AKI due to various aetiologies were subjected to Acute stylet PD. The clinical Outcome, demographic, biochemical and treatment data was assessed. Descriptive statistics was used to analyze the data.

RESULTS

A total of 79 (41 anuric, 33 oliguric and 5 nonoliguric) patients were included in the study. Sepsis was the predominant cause of AKI. Recovery was seen in 34% of patients. Patients with relatively preserved urine output recovered with PD in comparison to the anuric patients (p value <0.01). 58% of patients, majority of whom were anuric needed Hemodialysis (HD) in due course (7 ± 3 days) of time. The mortality in our study was 7.5%.

CONCLUSIONS

Acute stylet PD can be considered as a modality of Renal Replacement Therapy (RRT) to treat a selected (oliguric, nonoliguric) group of AKI patients and as a bridge therapy for HD in those AKI patients in anuria.

Rhabdomyolysis as a manifestation of a metabolic disease: a case report

Rhabdomyolysis is a process of muscle destruction that can present with varying clinical manifestations. In pediatric patients, its main etiology is infectious diseases. We present a previously healthy adolescent who was admitted to our emergency department with a four-day history of myalgia, muscle weakness and dark urine. At presentation, she was dehydrated. Blood analysis revealed acute renal failure and increased muscular enzymes.

She was transferred to our pediatric intensive care unit. Medical therapies for correction of dehydration and the ionic and metabolic consequences of renal failure were performed. Due to oliguria, renal replacement therapy was initiated. An etiological investigation revealed a beta-oxidation defect. Metabolic diseases are a known cause of rhabdomyolysis. Muscular destruction should be diagnosed early in order to avoid its potential consequences. Generally, the treatment of rhabdomyolysis is conservative, although in some situations, a more invasive approach is needed.

[Multi-organ failure after massive Levothyroxine ingestion: case report]

Levothyroxine is the drug of choice prescribed worldwide for the treatment of Hypothyroidism. The exact daily dosage, mode of consumption and refractoriness to therapy are still subject of discussion. The intoxication with levothyroxine is rare and with severe complications in adults; on the contrary, high prevalence and benign course is observed in pediatric age. We report the case of a 56 year-old woman, presented to the emergency department after intentional ingestion of massive levothyroxine overdose , with acute renal failure, severe disturbances of cardiovascular and central nervous system, that required intensive care support. In absence of a specific treatment, plasmapheresis has been used with good results, despite important clinical complications. In fact the clinical applications of plasmapheresis are rapidly increasing in number and scope: the plasmapheresis appears to be a very important tool for the treatment of acute and severe forms of thyrotoxicosis due to l-thyroxine intoxication.

Derivation of urine output thresholds that identify a very high risk of AKI in patients with septic shock

BACKGROUND AND OBJECTIVES

To promote early detection of AKI, recently proposed pretest probability models combine sub-Kidney Disease Improving Global Outcomes (KDIGO) AKI criteria with baseline AKI risk. The primary objective of this study was to determine sub-KDIGO thresholds that identify patients with septic shock at highest risk for AKI.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

This was a retrospective analysis of 390 adult patients admitted to the medical intensive care unit (ICU) of a tertiary, academic medical center with septic shock between January 2008 and December 2010. Hourly urine output was collected from the time of septic shock recognition (hour 0) to hour 96, urine catheter removal, or ICU discharge (whichever occurred first). All available serum creatinine (SCr) measurements were collected until hour 96. The AKI pretest probability model was assessed during the first 12 hours of resuscitation and included the initial episode of oliguria, increase from baseline to peak SCr level, and Acute Physiology and Chronic Health Evaluation (APACHE) III score in a multivariable receiver-operator characteristic (ROC) analysis. The primary outcome was the incidence of stage II or III (stage II+) AKI defined by KDIGO criteria. Secondary outcomes included the need for RRT and 28-day mortality.

RESULTS

Ninety-eight (25%) patients developed stage II+ AKI after septic shock recognition. APACHE III score and increase in SCr level in the first 12 hours were not statistically associated with stage II+ AKI in multivariable ROC analysis. Consecutive oliguria for 3 hours had fair predictive ability for achieving stage II+ AKI criteria (area under ROC curve, 0.73; 95% confidence interval [95% CI], 0.68 to 0.78), and oliguria for 5 hours demonstrated optimal accuracy (82%; 95% CI, 79% to 86%).

CONCLUSIONS

Three to 5 hours of consecutive oliguria in patients with septic shock may provide a valuable measure of AKI risk. Further validation to support this finding is needed.

Hemodynamic and related challenges: monitoring and regulation in the postoperative period

The clinician caring for patients in the immediate postoperative period must maintain a high index of suspicion for the development of complications. Evolving illness manifests itself throughout the continuum of care and must be recognized and aggressively managed to ensure optimal outcome. This article discusses common hemodynamic problems encountered in the postanesthesia care unit. These problems are presented in a clinical framework that is familiar to experienced practitioners and recognizable to trainees. This article reviews of these common problems including relevant physiologic principles; effects on hemodynamics; and a logical approach to evaluation, monitoring, and management of a complex postoperative patient.

Factors associated with acute renal failure in falciparum malaria infected patients

To identify factors associated with acute renal failure among patients with severe falciparum malaria (MARF), we studied 189 severe malaria patients admitted to the Hospital for Tropical Diseases, Faculty of Tropical Medicine, Mahidol University, in Bangkok, Thailand. Among these, 63 had MARF, and 126 did not. Baseline clinical demographics and laboratory variables were evaluated with univariate analysis. Logistic regression was used to ascertain adjusted odds ratios. By univariate analysis, factors associated with MARF included male gender, fever duration > 4 days, patients who lived in a non-endemic area prior to malaria infection, body mass index > 18.5 kg/m(2), oliguria, abdominal pain, impaired consciousness, jaundice, anemia, liver enlargement, total white blood cell count > 10x10(9)/1, total bilirubin > 3 mg/dl, aspartate aminotransferase > 120 U/l, alanine aminotransferase > 120 U/l, albumin < 3 g/dl, fever clearance time >72 hours, and parasite clearance time > 72 hours. A hemoglobin > 10 g/dl, patients living in a malaria endemic area, non-oliguria on the day of admission, and splenomegaly were negatively associated with MARF. After multivariate logistic regression, oliguria during the first 24 hours of admission and a history of living in a nonendemic area prior to malarial infection were factors associated with MARF. We conclude the most significant factors associated with MARF were oliguria on the day of admission and living in a non-endemic area prior to malaria infection.

Successful treatment of life-threatening pentoxifylline intoxication by high-flux hemodialysis

High-flux hemodialysis is the method of choice for the treatment of many life threatening intoxications. Reports on intoxication with pentoxifylline are rare, and although pharmacokinetic properties of the drug suggest a potential role for hemodialysis, there are no published reports on extracorporeal treatment attempts. We report the first case of successful treatment of potentially life-threatening pentoxifylline intoxication by high-flux hemodialysis. Based on this single case, dialysis should be considered, especially in anuric patients with pentoxifylline intoxication.

How to ensure patient observations lead to effective management of oliguria

Fluid balance is essential for normal functioning of the body. Oliguria (poor urine output) is usually associated with low circulatory blood volume (hypovolaemia), and can be a sign that a patient is acutely ill and deteriorating. Early warning scoring systems should identify the condition so that appropriate interventions can be undertaken to restore urine output and protect renal function.

Rhabdomyolysis

Rhabdomyolysis is the disintegration of striated muscles resulting in the release of muscular cell contents into the extracellular fluid. Crush syndrome is systemic manifestations caused by rhabdomyolysis; the most important component of crush syndrome is acute kidney injury. Non-physical and physical causes play a role in the aetiology of rhabdomyolysis. Clinical spectrum varies from asymptomatic elevation in creatine kinase to acute tubular necrosis and multiorgan failure. Myoglobinuria, increased serum creatine kinase level and hyperkalaemia are the most important laboratory parameters. Vigorous hydration with isotonic saline followed by alkaline solutions and mannitol are useful in the treatment of rhabdomyolysis.

Post-coronarography application of continuous veno-venous hemofiltration in the prevention of contrast nephropathy in patients with complex multisystem deficiency

BACKGROUND

An increased admission of high-risk patients to diagnostic and interventional radiological procedures with contrast medium has resulted in an increase of contrast-induced nephropathy, which now represents the third main cause of hospital-acquired acute renal failure. The pathogenic mechanism of contrast-induced nephropathy (CN) is unclear, but there is much evidence which indicated an interaction between direct tubular cytotoxicity and osmotic/hemodynamic effects. Continuous veno-venous hemofiltration (CVVH) has shown possible benefits in preventing CN. It is not understood when and how prophylactic strategies should be used either in pharmacological therapies or in continous renal replacement therapy (CRRT) approaches. The aim of this study was to evaluate the efficiency of the CVVH technique in preventing CN secondary to emergency radiological procedures in very high-risk patients.

PATIENTS AND METHODS

Twelve patients with severe chronic renal impairment (serum creatinine concentration >2 mg/dl with an estimated glomerular filtration rate (eGFR) <40 ml/min) in association with at least two severe comorbidities (such as previous acute myocardial infarction in hypertensive or diabetic patients obesity, cardiac failure with ejection fraction <40%, severe hypotension) were treated with CVVH after coronarography using an iso-osmolar contrast medium (Visipaque, Iodixanol), with or without percutaneous transluminal coronary angioplasty. Adverse events and their association with the interventional radiological procedure were investigated after hemofiltration.

RESULTS

Statistically significant differences were observed for both eGFR and serum creatinine at different time points (pre-, post- and 7 days after the procedure) at p<0.05. Statistical analysis of all the variables related to the radiological procedure and the hemofiltration technique did not cause any modification of renal function between the pre- and post-procedure values. No patient showed signs of cardiovascular instability, nor were any episodes of marked hypotension reported during the dialysis session. No patient showed any adverse effects related to the interventional radiological procedure or to the CVVH technique. Renal function, according to serum creatinine concentration and the e-GFR calculation (Cockcroft), did not worsen but had improved when the patients left hospital, with function rates statistically significantly better compared to that on hospital admission, even 7 days after the radiological procedure.

CONCLUSION

The present study suggests the efficiency of the CVVH technique in preventing CN in high-risk patients who need to undergo interventional radiological cardiovascular procedures involving the administration of an iodine-based contrast medium.

Hemolytic uremic syndrome associated with pneumococcal pneumonia in Taiwan

Streptococcus pneumoniae ( S. pneumoniae ) has been associated with hemolytic uremic syndrome (HUS), which is an unusual but serious disease in childhood. We conducted a retrospective review of children aged less than 18 years with S. pneumoniae -associated HUS in northern Taiwan from January 2000 to June 2005. The demographic characters, clinical courses, and outcomes were analyzed. Seven children (three girls, four boys) with S. pneumoniae -associated HUS were studied. The median age at onset of HUS was 40 months (range: 25-60 months). The median duration of hospital stay was 36 days (range: 15-50 days). The interval between the onset of illness attributable to S. pneumoniae and the development of HUS was around 1-2 weeks. The onset of oliguria developed within 2 weeks after illness. Six patients required dialysis with median duration of 16 days. Three patients had leukopenia as the initial presentation. All seven patients had pneumococcal pneumonia complicating with empyema, and two of them received decortication via video-assisted thoracoscopic surgery. Between patients who needed dialysis or not, there was no significant difference in age, sex, duration of thrombocytopenia, incidence of extra-renal complications, such as hepatitis, pancreatitis, and hypertension, and length of hospital stay. The seven patients survived with normal renal function. HUS is a potentially fatal complication of S. pneumoniae infection. Clinicians managing patients with pneumococcal pneumonia with empyema accompanied by leukopenia should beware of the development of HUS. The long-term prognosis for recovery of renal function appears to be good in these patients in northern Taiwan.

Early isovolaemic haemofiltration in oliguric patients with septic shock

OBJECTIVE

To evaluate the effects of early short-term, isovolaemic haemofiltration at 45 ml/kg/h on physiological and clinical outcomes in patients with septic shock.

DESIGN

Retrospective study before and after a change of unit protocol (study period 8 years).

SETTING

Intensive care unit of metropolitan hospital.

PATIENTS

Eighty patients with septic shock.

INTERVENTIONS

Introduction of a new septic shock protocol based on early isovolaemic haemofiltration (EIHF). In the pre-EIHF period (before), 40 patients received conventional supportive therapy. In the post-EIHF period (after), 40 patients received EIHF at 45 ml/kg/h of plasma-water exchange over 6 h followed by conventional continuous venovenous haemofiltration (CVVH). Anticoagulation policy remained unchanged.

MEASUREMENTS AND MAIN RESULTS

The two groups were comparable for age, gender and baseline APACHE II score. Delivered haemofiltration dose was above 85% of prescription in all patients. PaO2/FiO2 ratio increased from 117+/-59 to 240+/-50 in EIHF, while it changed from 125+/-55 to 160+/-50 in the control group (p<0.05). In EIHF patients, mean arterial pressure increased (95+/-10 vs 60+/-12 mmHg; p<0.05), and norepinephrine dose decreased (0.20+/-2 vs 0.02+/-0.2 microg/kg/min; p<0.05). Among EIHF patients, 28 (70%) were successfully weaned from the ventilator compared with 15 (37%) in the control group (p<0.01). Similarly, 28-day survival was 55% compared with 27.5% (p<0.05). Length of stay in the ICU was 9+/-5 days compared with 16+/-4 days (p<0.002).

CONCLUSIONS

In patients with septic shock, EIHF was associated with improved gas exchange, haemodynamics, greater likelihood of successful weaning and greater 28-day survival compared with conventional therapy.

Oliguria, Volume Overload, Na+ Balance, and Diuretics

This article discusses the pathophysiology and treatment of common fluid and electrolyte disorders in the ICU. The presence of oliguria should alert the intensivist to identify the underlying cause rather than to resort reflexively to measures, such as diuretics or dopamine, to establish urine flow. Hypo- and hypernatremia, which are exceedingly commonly in the ICU setting, also are discussed using a pathophysiologic approach.

Continuous veno-venous hemofiltration for the treatment of contrast-induced acute renal failure after percutaneous coronary interventions

Acute renal failure (ARF) requiring hemodialysis after percutaneous coronary interventions (PCI) is a serious complication with poor prognosis. Hemodialysis-induced hypotension may have deleterious cardiovascular effects, especially in high-risk patients. Ultrafiltrate removal and simultaneous fluid replacement with a solution similar to plasma for high-volume controlled hydration can be obtained with hemodynamic stability by continuous veno-venous hemofiltration (CVVH). We prospectively assessed the safety and effectiveness of percutaneous CVVH (Y-shaped double-lumen catheter, circuit originating from and terminating in the femoral vein) in 33 consecutive patients (23 men and 10 women; mean age, 69 +/- 9 years) who, after PCI, developed oligo-anuric ARF, associated in 20 of them with congestive heart failure. All patients received a concomitant infusion of furosemide (500-1000 mg/day) and dopamine (2 microg/kg/min). During CVVH, the average fluid volume replacement and body fluid net reduction were 1000 +/- 247 and 75 +/- 48 ml/hr, respectively. Treatment with CVVH continued for 4.7 +/- 2.7 days and corrected fluid overload in all cases. No patient experienced systemic hypotension or hypovolemia. Diuresis recovered in 32 (97%) patients, who showed a parallel improvement of renal function parameters. One patient required chronic dialysis. In-hospital and 1-year mortality was 9.1% and 27.3%, respectively. In conclusion, our data indicate that CVVH is a safe and effective therapy of radiocontrast-induced ARF following PCI. It temporarily replaces renal function without deleterious cardiovascular effects, allowing the kidney to recover from the nephrotoxic injury. However, despite promising early results, large randomized trials are required to define the role of CVVH in ARF after PCI.

Care of the critically ill parturient: oliguria and renal failure

The incidence of acute renal failure in pregnancy has decreased. This decrease is less marked in developing countries in which resources are more scarce. The clinical diagnosis of acute renal failure is crude due to the variability of clinical signs and the late occurrence of basic biochemical abnormalities. Obstetric and gynaecological diseases are found among the traditional pre-renal, intra-renal and post-renal causes of acute renal failure. The cornerstone of management is the identification of high-risk cases and the prevention of acute renal failure by maintaining intravascular volume. The evidence for the efficacy of other prophylactic medical interventions, such as the use of loop diuretics, mannitol, low-dose dopamine and others, is poor. Management of established acute renal failure includes restoration of intravascular volume, treatment of any reversible causes, especially pregnancy complications such as pre-eclampsia, strict fluid balance and correction of any electrolyte abnormality or metabolic acidosis. Dialysis is a supportive measure until the kidneys recover.

AN-69 membrane reactions are pH-dependent and preventable

We report two pediatric patients who required blood priming for continuous venovenous hemodiafiltration. Both of these patients developed a significant hypotensive episode with initiation of continuous venovenous hemodiafiltration with immediate resolution on discontinuation. The most notable common characteristics of these patients were the use of the Multi-flo 60 (AN-69) dialyzer membrane and blood priming. No similar episodes were encountered when patients were primed with saline or albumin. The AN-69 membrane is exquisitely pH sensitive. The lower the pH concentration of the blood passing by the membrane, the greater the activation of bradykinin, a known hypotensive-inducing agent, by the dialyzer. On review of blood available from our blood bank, the following parameters became apparent. The pH of standard blood available from our blood bank ranged from 6.1 to 6.4. The blood obtained from our blood bank had significant hyperkalemia, hyponatremia, and hypocalcemia. No reactions were noted when patients were primed with normal saline, which has a pH of around 5.9. We speculate that the presence of endogenous blood substances, such as bradykinin, may have induced the hypotensive episodes. We describe two techniques we developed that should allow for the increased safe and effective use of the AN-69 membranes in continuous venovenous hemodiafiltration circuits. These observations indicate the requirement for careful and close attention to detail when delivering renal replacement therapy to anyone, but especially patients weighing less than 10 kg.

10% hydroxyethyl starch for plasma expansion in the treatment of severe ovarian hyperstimulation syndrome. A case report

BACKGROUND

Severe ovarian hyperstimulation syndrome is a complication of hormonal therapy for in vitro fertilization and carries the risk of renal failure. The injection of 6% hydroxyethyl starch has been used as a preventive measure.

CASE

A 33-year-old woman was admitted with severe ovarian hyperstimulation syndrome after receiving gonadotropins as part of our in vitro fertilization protocol. Despite treatment with saline, albumin and abdominal taps, oliguria developed on the third day. The patient was transferred to the general intensive care unit and treated with 10% hydroxyethyl starch, furosemide and a further abdominal tap. Recovery was rapid.

CONCLUSION

Ten percent hydroxyethyl starch is an efficient plasma expander. It is safe, biohazard free and cost-effective. It seems to effectively control severe ovarian hyperstimulation syndrome and to overcome acute prerenal failure. Larger prospective studies are necessary to further evaluate its role in the treatment of severe ovarian hyperstimulation syndrome.

Oliguria in the ICU. Systematic approach to diagnosis and treatment

Perioperative oliguria is common but rarely implies acute renal failure. We should interpret oliguria as a sign of intravascular hypovolemia and treat it as prerenal until proven otherwise. On the other hand, the absence of oliguria does not exclude acute renal failure. The most reliable clinical indicator of progressive renal dysfunction is a serial decline in creatinine clearance estimation, a measure of glomerular filtration rate.

Reversible acute renal failure with prolonged oliguria and gross hematuria in a case of paroxysmal nocturnal hemoglobinuria

A 39-year-old man, a known case of paroxysmal nocturnal hemoglobinuria (PNH), developed severe acute renal failure, prolonged oliguria, and grossly bloody urine. After 8 weeks and 24 sessions of hemodialysis he became polyuric, and his renal function normalized after 10 weeks. The diagnosis of PNH was reconfirmed.

Prognosis of patients with acute renal failure requiring dialysis: results of a multicenter study

Despite several decades of clinical experience, the mortality rate for patients with acute renal failure (ARF) requiring dialysis remains high, and the evaluation of the patients prognosis has been difficult. To date, the Acute Physiology and Chronic Health Evaluation II (APACHE II) scoring system has been used more frequently for prediction in studies of ARF than any other scoring system, but has not been prospectively validated in controlled multicenter studies of this entity. In a multicenter, prospective, controlled trial evaluating the use of biocompatible hemodialysis membranes (BCMs) in patients with ARF, we evaluated the extent to which the APACHE II scoring system, based on the physiological variables in the 24 hours before the onset of dialysis and the presence or absence of oliguria, is predictive of outcome. Analysis of survival and recovery of renal function for the 153 patients treated in this study show that APACHE II scores are predictive both of survival and recovery of renal function, whether analyzed separately by type of dialysis membrane used (BCM or bioincompatible [BICM]) or for both groups combined (all P < 0.01). There was no evidence of a significant center effect or interaction of APACHE II score with dialysis membrane in our study. After adjusting for the APACHE II score, there was a positive effect of the BCM on both probability of survival (P < 0.05) and recovery of renal function (P < 0.01). In patients dialyzed with BCMs, oliguria at onset of dialysis had an adverse effect on both survival and recovery of renal function (both P < 0.01). Receiver operator curves (ROCs) using APACHE II score and the use of BCMs in nonoliguric patients yielded a statistically significant improvement versus the use of APACHE II score alone in the area under the curve (AUC) for survival (0.747 to 0.801; P < 0.05) and recovery of renal function (0.712 to 0.775; P < 0.05). We conclude that the use of the APACHE II score determined at the time of initiation of dialysis for patients with ARF is a statistically significant predictor of patient survival and recovery of renal function. The use of the APACHE II score measured at the time of dialysis initiation, especially when modified by the presence or absence of oliguria, should help in predicting outcome when evaluating interventions for patients with ARF.

Indications and criteria for initiating renal replacement therapy in the intensive care unit

The decision to initiate renal replacement therapy is usually based on a careful assessment of conflicting priorities in the care of critically ill patients. It is particularly difficult because of the lack of information on what are the optimal criteria and indications for the application of renal replacement therapy (RRT) in the intensive care unit (ICU). As we will discuss in this paper, even though there are several time-honored indications for initiating dialytic therapy in patients with near end-stage renal failure, such indications may not apply to the management of acute renal failure (ARF). In fact, there are several reasons why a more aggressive approach and an earlier intervention may be justified in the ICU.

Reversing oliguria in critically ill patients

Oliguria is a common occurrence in the ICU setting. In patients with preserved renal function, fluid challenges or low doses of diuretics are generally successful. In patients with oliguric renal failure, it is still essential to ensure adequate intravascular fluid volume, especially in critically ill patients. Loop diuretics remain the mainstay of treatment. When diuretic resistance is encountered, physicians should consider further optimization of hemodynamics, alternative loop diuretics, and combined drug therapy. In some cases, continuous renal replacement therapy can be very effective. Yet, while these interventions can help reduce the morbidity of severe volume overload, they have not been shown to improve mortality rates.

Single needle venovenous extracorporeal membrane oxygenation using a nonocclusive roller pump for rescue in infants and children

In 1993, J.Y. Chevalier described a single needle venovenous extracorporeal membrane oxygenation (ECMO) system using a nonocclusive roller pump and alternating clamps for pulmonary support in neonates. We modified this system to use it in older children as well and for additional indications. Introducing a double raceway and 2 different sizes of tubing sets and performing percutaneous approach, we treated 21 children (age 1 day to 49 months) using this system. Indications for treatment were hypoxia and hypoxic induced myocardial dysfunction resulting from pulmonary failure, sepsis, and congenital defects. Of the children treated for neonatal indications, 7/9 survived. For 2 children ECMO was terminated because of intraventricular hemorrhage (IVH). In the pediatric group 5/7 of the children could be weaned from ECMO, and 2 children died after more than 30 days on ECMO. Two of the children who had been almost completely weaned died later because of therapy withdrawal following a brain death diagnosis. In the cardiac group, 3/5 of the children survived. We conclude that the described system is an effective venovenous ECMO system that reduces invasivity and expenditure.

Impact of continuous hemofiltration on cytokines and cytokine inhibitors in oliguric patients suffering from systemic inflammatory response syndrome

The impact of continuous hemofiltration (CHF) using a polyacrylonitrile membrane on the kinetics of tumor necrosis factor alpha (TNF alpha), interleukin-1 beta (IL-1 beta), and their inhibitors (soluble TNF receptors [sTNFrI, sTNFrII], interleukin-1 receptor antagonist [IL-1Ra]) was assessed in nine oliguric patients suffering from systemic inflammatory response syndrome. Blood and plasma flow (Qb, Qp), sieving coefficient (SC), plasma and ultrafiltrate clearances (Kp, Kuf), and plasma extraction rates (ERp) were calculated at different time points using standard formulas. No significant improvement of hemodynamics or gas exchange was noted following HF but a significant increase in serum bicarbonate occurred after 24 h (P < 0.05). TNF alpha was detected in plasma from all patients (153 +/- 2.3 pg/mL [mean +/- SEM]). None of the patients had detectable IL-1 beta levels. High levels of the TNF receptors (sTNFrI 20.338 +/- 2.431 pg/mL; sTNFrII 17.839 +/- 2.630 pg/mL) and IL-1Ra (19.775 +/- 3.943 pg/mL) were found in all patients. Upon initiation of hemofiltration (HF), the mean individual sTNFrI/TNF alpha ratio amounted to 269 +/- 84.6 and the sTNFrII/TNF alpha ratio to 249 +/- 91.8. Mean ultrafiltrate volume (Vuf) was 11.8 +/- 0.4 L/day. Appreciable sieving of IL-1Ra (SC 0.45 +/- 0.10), but not of the other cytokines, was noted (SC TNF alpha, sTNFrI, sTNFrII < 0.09). Despite minimal Kuf of TNF alpha, sTNFrI, and STNFrII (Kuf < 0.8 mL/min), appreciable Kp was noted, suggesting that membrane adsorption occurs (Kp approximately 8 mL/min). There was a nonsignificant increase of the ratios between both TNF receptors and TNF alpha across the filter (sTNFrI/TNF alpha ratio [pre] 231 +/- 37.9 versus [post] 312 +/- 75.3); sTNFrII/TNF alpha ratio [pre] 211 +/- 42.1 versus [post] 291 +/- 79.3). Appreciable Kp of IL-1Ra was noted (Kp 17.3 +/- 1.61 mL/min), which was only in part due to Kuf (4.0 +/- 0.86 mL/min). There was a significant decrease of IL-1Ra levels across the membrane, both overall ([pre] 20.223 +/- 2.282 versus [post] 16.637 +/- 2.039 pg/mL; P < 0.01) and at different time points (P < 0.01). Only for IL-1Ra was significant extraction from plasma noted (ERp 26 +/- 6.0%). Plasma levels of TNF alpha, sTNFrI, sTNFrII, and IL-1Ra were not altered by 24 h of CHF. In conclusion, both cytokines and cytokine inhibitors can be removed from the circulation, either by convective transport or by membrane adsorption. Using low-volume HF (Vuf approximately 12 L/day), no impact on cytokine plasma levels nor the patients hemodynamics or gas exchange was noted. The appreciable SC of IL-1Ra (0.45), however, suggests that HF with high(er) UF volumes (> 50 L/day) may be able to achieve reductions in plasma levels of some peptide (anti)mediators. However, whether this aspecific elimination of both mediators and antimediators may alter the clinical course in critically ill patients remains to be investigated.

Acute renal failure in a teaching hospital

This was a retrospective study of the clinical course of 164 adult inpatients with acute renal failure (ARF) at the Hospital of the University of Science Malaysia admitted from June 1986 to May 1990. The mean age was 49.8 +/- 17.2 years. 33.5%, 54.9% and 11.6% were surgical, medical and obstetrical patients respectively. Obstructive uropathy, poor cardiac output or decrease in intravascular volume and infection accounted for more than 67% of the cases. Acute renal failure was present at admission in 113 (69%) patients. The majority of the patients (80%) had nonoliguric acute renal failure with daily output of urine of more than 400 ml. Compared with nonoliguric patients, oliguric patients had higher mortality (56.3% vs 18.9%, p < 0.01), and needed dialysis more frequently (43.8% vs 12.9%, p < 0.01). Early recognition of acute renal failure, improvement in early treatment of renal stones and discerning use of nephrotoxic drugs could result in decrease in incidence and severity of renal failure.

Plasma exchange in patients with acute renal failure in the course of multiorgan failure

Multiorgan failure (MOF) due to intoxication, trauma or sepsis in the progressive late stages always include acute renal failure (ARF). The prognosis of these patients is poor despite adequate dialysis. This study included 27 consecutive patients (20 men and 7 women, age range 15-77 years) with a rapid progress of MOF including ARF, who were treated by plasma exchange as an attempt to reverse the progress of MOF. Twenty-three of the patients suffered from a septic shock. Oliguria or anuria was present in all, dialysis was performed in 16 of them, and mechanical respiratory aid in 17. Plasma exchange was performed 1-10 times and almost exclusively by centrifuge technique, using albumin and/or liquid stored plasma (in a few cases fresh frozen plasma) as colloidal replacement fluid. Twenty-two patients survived (81%) and 5 patients died. The reasons of death were cerebral haemorrhagia, brain abscess, myocardial sudden death, relapsing sepsis from multiple hepatic abscesses and a not drained psoas abscess. All survivors could leave hospital recovered from renal failure with few other sequelae. The plasma exchange technique is easy to perform despite low blood pressures by using a vein to vein access. Plasma exchange, therefore, may be tried to reverse late stages of multiorgan failure.

[Treatment of choleriform diarrhea during pregnancy]

A retrospective review was conducted of the clinical histories of 43 pregnant women treated for acute diarrheal disease in the emergency ward of the María Auxiliadora Departmental Hospital (HADMA) in Lima, Peru, and 32 of the histories were selected for this study. These 32 patients had been admitted to the cholera treatment unit (CTU) of the HADMA for acute choleraic diarrhea with moderate or severe dehydration. The objective was to analyze the clinical evolution of the patients, their response to isotonic rehydration therapy (0.9% saline solution), and the consequences for their pregnancies. The following variables were examined: age; trimester of pregnancy; heart rate and mean blood pressure (MBP) at admission; number of hours since last normal urination; duration of diarrhea; degree of dehydration; volume of diarrhea and vomiting; volume of saline solution administered in the first 2 hours and in total; volume of multi-electrolyte solution (MES) or oral rehydration salts (ORS) administered from the second to the sixth hour and in total; and hours between admission to the emergency ward and transfer to the cholera treatment unit (EME/CTU). Logistic regression analysis revealed a direct and statistically significant correlation between the time of recovery of diuresis and the EME/CTU (P = 0.001; r = 0.65), as well as between time of recovery of diuresis and the volume of diarrhea in the first 4 hours.(ABSTRACT TRUNCATED AT 250 WORDS)

Treatment of biguanide-induced lactic acidosis: reproposal of the "physiological" approach and review of the literature

We report a case of severe biguanide-induced lactic acidosis which did not respond to symptomatic alkali treatment via either intravenous bicarbonate infusion or bicarbonate-dialysis. We thus initiated a therapeutic strategy based on insulin and thiamine only in order to reactivate the pyruvate oxidative pathway, in which both drugs play important roles as cofactors. This original "physiological" approach proved effective, and further alkali administration was unnecessary. Our results prompted a review of the literature on the treatment of biguanide-induced lactic acidosis, a situation in which the absence of precise therapeutic rules can undoubtedly affect both the evolution and the prognosis of the syndrome.

Ibuprofen overdose complicated by renal failure, adult respiratory distress syndrome, and metabolic acidosis

Acute ingestion of ibuprofen commonly results in no symptoms, or minor gastrointestinal or central nervous system manifestations. While most cases of ibuprofen overdose do well, serious toxicity may occur, and is difficult to predict. A case of ibuprofen overdose is presented in which the course was complicated by metabolic acidosis, adult respiratory distress syndrome, and renal failure necessitating prolonged dialysis.