A quantitative analysis of the acidosis of cardiac arrest: a prospective observational study

INTRODUCTION: Metabolic acidosis is common in patients with cardiac arrest and is conventionally considered to be essentially due to hyperlactatemia. However, hyperlactatemia alone fails to explain the cause of metabolic acidosis. Recently, the Stewart–Figge methodology has been found to be useful in explaining and quantifying acid–base changes in various clinical situations. This novel quantitative methodology might also provide useful insight into the factors responsible for the acidosis of cardiac arrest. We proposed that hyperlactatemia is not the sole cause of cardiac arrest acidosis and that other factors participate significantly in its development. METHODS: One hundred and five patients with out-of-hospital cardiac arrest and 28 patients with minor injuries (comparison group) who were admitted to the Emergency Department of a tertiary hospital in Tokyo were prospectively included in this study. Serum sodium, potassium, ionized calcium, magnesium, chloride, lactate, albumin, phosphate and blood gases were measured as soon as feasible upon arrival to the emergency department and were later analyzed using the Stewart–Figge methodology. RESULTS: Patients with cardiac arrest had a severe metabolic acidosis (standard base excess -19.1 versus -1.5; P < 0.0001) compared with the control patients. They were also hyperkalemic, hypochloremic, hyperlactatemic and hyperphosphatemic. Anion gap and strong ion gap were also higher in cardiac arrest patients. With the comparison group as a reference, lactate was found to be the strongest determinant of acidosis (-11.8 meq/l), followed by strong ion gap (-7.3 meq/l) and phosphate (-2.9 meq/l). This metabolic acidosis was attenuated by the alkalinizing effect of hypochloremia (+4.6 meq/l), hyperkalemia (+3.6 meq/l) and hypoalbuminemia (+3.5 meq/l). CONCLUSION: The cause of metabolic acidosis in patients with out-of-hospital cardiac arrest is complex and is not due to hyperlactatemia alone. Furthermore, compensating changes occur spontaneously, attenuating its severity

Recent Clinical Advances in the Management of Critically Ill Patients with Acute Renal Failure

Background: Significant progress has been made in the field of renal replacement therapy for critically ill patients with acute renal failure (ARF) over the past few years. This review highlights these developments. Methods: Recent studies assessing the clinical utility of the RIFLE classification system for the diagnosis of ARF were reviewed. Clinical outcome studies evaluating the effect of continuous renal replacement therapy (CRRT) dose and timing of initiation were assessed. The final review topic was the effect of dialysis modality on the recovery of renal function in ARF patients. Conclusions: Based on recent clinical studies, the increasing use of the RIFLE criteria is justified, as this approach appears to be a robust method for both the diagnosis of and prognostication in ARF. A large randomized trial involving convective CRRT supports the commonly used prescription of 35 ml/ kg/h in clinical practice. Moreover, numerous recent outcome studies, also largely involving convective CRRT, provide a clinical rationale for the increasingly common clinical practice of earlier initiation. Finally, several recent studies suggest CRRT, relative to conventional hemodialysis, results in a greater rate of renal recovery in ARF patients

Cost of acute renal replacement therapy in the intensive care unit: results from The Beginning and Ending Supportive Therapy for the Kidney (BEST Kidney) Study

INTRODUCTION: Severe acute kidney injury (AKI) can be treated with either continuous renal replacement therapy (CRRT) or intermittent renal replacement therapy (IRRT). Limited evidence from existing studies does not support an outcome advantage of one modality versus the other, and most centers around the word use both modalities according to patient needs. However, cost estimates involve multiple factors that may not be generalizable to other sites, and, to date, only single-center cost studies have been performed. The aim of this study was to estimate the cost difference between CRRT and IRRT in the intensive care unit (ICU). METHODS: We performed a post hoc analysis of a prospective observational study among 53 centers from 23 countries, from September 2000 to December 2001. We estimated costs based on staffing, as well as dialysate and replacement fluid, anticoagulation and extracorporeal circuit. RESULTS: We found that the theoretic range of costs were from $3,629.80/day more with CRRT to$378.60/day more with IRRT. The median difference in cost between CRRT and IRRT was $289.60 (IQR 830.8-116.8) per day (greater with CRRT). Costs also varied greatly by region. Reducing replacement fluid volumes in CRRT to <or= 25 ml/min (approximately 25 ml/kg/hr) would result in$67.20/day (23.2%) mean savings. CONCLUSIONS: Cost considerations with RRT are important and vary substantially among centers. We identified the relative impact of four cost domains (nurse staffing, fluid, anticoagulation, and extracorporeal circuit) on overall cost differences, and hospitals can look to these areas to reduce costs associated with RRT

Defining the characteristics and expectations of fluid bolus therapy : A worldwide perspective

Purpose: The purpose of the study is to understand what clinicians believe defines fluid bolus therapy (FBT) and the expected response to such intervention. Methods: We asked intensive care specialists in 30 countries to participate in an electronic questionnaire of their practice, definition, and expectations of FBT. Results: We obtained 3138 responses. Despite much variation, more than 80% of respondents felt that more than 250 mL of either colloid or crystalloid fluid given over less than 30 minutes defined FBT, with crystalloids most acceptable. The most acceptable crystalloid and colloid for use as FBT were 0.9% saline and 4% albumin solution, respectively. Most respondents believed that one or more of the following physiological changes indicates a response to FBT: a mean arterial pressure increase greater than 10 mm Hg, a heart rate decrease greater than 10 beats per minute, an increase in urinary output by more than 10 mL/h, an increase in central venous oxygen saturation greater than 4%, or a lactate decrease greater than 1 mmol/L. Conclusions: Despite wide variability between individuals and countries, clear majority views emerged to describe practice, define FBT, and identify a response to it. Further investigation is now required to describe actual FBT practice and to identify the magnitude and duration of the physiological response to FBT and its relationship to patient-centered outcomes. (C) 2016 Elsevier Inc. All rights reserved.Peer reviewe

Defining the characteristics and expectations of fluid bolus therapy: a worldwide perspective

Purpose: The purpose of the study is to understand what clinicians believe defines fluid bolus therapy (FBT) and the expected response to such intervention. Methods: We asked intensive care specialists in 30 countries to participate in an electronic questionnaire of their practice, definition, and expectations of FBT. Results: We obtained 3138 responses. Despite much variation, more than 80% of respondents felt that more than 250 mL of either colloid or crystalloid fluid given over less than 30 minutes defined FBT, with crystalloids most acceptable. The most acceptable crystalloid and colloid for use as FBT were 0.9% saline and 4% albumin solution, respectively. Most respondents believed that one or more of the following physiological changes indicates a response to FBT: a mean arterial pressure increase greater than 10 mm Hg, a heart rate decrease greater than 10 beats per minute, an increase in urinary output by more than 10 mL/h, an increase in central venous oxygen saturation greater than 4%, or a lactate decrease greater than 1 mmol/L. Conclusions: Despite wide variability between individuals and countries, clear majority views emerged to describe practice, define FBT, and identify a response to it. Further investigation is now required to describe actual FBT practice and to identify the magnitude and duration of the physiological response to FBT and its relationship to patient-centered outcomes.Facultad de Ciencias Médica

Validity of low-efficacy continuous renal replacement therapy in critically ill patients

  The 1980s saw the use of continuous arteriovenous hemofiltration whose intensity hemofiltration rate was only 3 or 4 mL kg-1 h-1. With the installation of a blood pump, this dose went up to 8 or 10 mL kg-1 h-1, and continued to increase, reaching about 20 mL kg-1 h-1 by the year 2000. Some studies found that a higher dose could be beneficial, and the world rapidly followed the trend, increasing the dose up to 35 mL kg-1 h-1. Then, two randomized control trials, namely the VA/NIH Acute Renal Failure Trial Network study and the RENAL study, came along in succession which changed the Kidney Disease: Improving Global Outcomes (KDIGO) recommendation to 20 to 25 mL kg-1 h-1. However, no good evidence exists to support this. Our recent multicenter retrospective studies from the JSEPTIC CRRT database show that the Japanese continuous renal replacement therapy dose of (14.3 mL kg-1 h-1) does not seem to have worse outcomes when compared with a higher dose.    The 1980s saw the use of continuous arteriovenous hemofiltration whose intensity hemofiltration rate was only 3 or 4 mL kg-1 h-1. With the installation of a blood pump, this dose went up to 8 or 10 mL kg-1 h-1, and continued to increase, reaching about 20 mL kg-1 h-1 by the year 2000. Some studies found that a higher dose could be beneficial, and the world rapidly followed the trend, increasing the dose up to 35 mL kg-1 h-1. Then, two randomized control trials, namely the VA/NIH Acute Renal Failure Trial Network study and the RENAL study, came along in succession which changed the Kidney Disease: Improving Global Outcomes (KDIGO) recommendation to 20 to 25 mL kg-1 h-1. However, no good evidence exists to support this. Our recent multicenter retrospective studies from the JSEPTIC CRRT database show that the Japanese continuous renal replacement therapy dose of (14.3 mL kg-1 h-1) does not seem to have worse outcomes when compared with a higher dose

Prediction Models and Their External Validation Studies for Mortality of Patients with Acute Kidney Injury: A Systematic Review

<div><p>Objectives</p><p>To systematically review AKI outcome prediction models and their external validation studies, to describe the discrepancy of reported accuracy between the results of internal and external validations, and to identify variables frequently included in the prediction models.</p><p>Methods</p><p>We searched the MEDLINE and Web of Science electronic databases (until January 2016). Studies were eligible if they derived a model to predict mortality of AKI patients or externally validated at least one of the prediction models, and presented area under the receiver-operator characteristic curves (AUROC) to assess model discrimination. Studies were excluded if they described only results of logistic regression without reporting a scoring system, or if a prediction model was generated from a specific cohort.</p><p>Results</p><p>A total of 2204 potentially relevant articles were found and screened, of which 12 articles reporting original prediction models for hospital mortality in AKI patients and nine articles assessing external validation were selected. Among the 21 studies for AKI prediction models and their external validation, 12 were single-center (57%), and only three included more than 1,000 patients (14%). The definition of AKI was not uniform and none used recently published consensus criteria for AKI. Although good performance was reported in their internal validation, most of the prediction models had poor discrimination with an AUROC below 0.7 in the external validation studies. There were 10 common non-renal variables that were reported in more than three prediction models: mechanical ventilation, age, gender, hypotension, liver failure, oliguria, sepsis/septic shock, low albumin, consciousness and low platelet count.</p><p>Conclusions</p><p>Information in this systematic review should be useful for future prediction model derivation by providing potential candidate predictors, and for future external validation by listing up the published prediction models.</p></div

Area under the receiver operating characteristic curves (AUROC) for hospital mortality reported in the original articles and external validation studies.

<p>Black horizontal bars: AUROC in original studies, gray columns: AUROC in external validation studies.</p