Renal dysfunction is common following resuscitation from out-of-hospital cardiac arrest

2024 RECOVER Guidelines: Monitoring. Evidence and knowledge gap analysis with treatment recommendations for small animal CPR

OBJECTIVE

To systematically review evidence on and devise treatment recommendations for patient monitoring before, during, and following CPR in dogs and cats, and to identify critical knowledge gaps.

DESIGN

Standardized, systematic evaluation of literature pertinent to peri-CPR monitoring following Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) methodology. Prioritized questions were each reviewed by Evidence Evaluators, and findings were reconciled by Monitoring Domain Chairs and Reassessment Campaign on Veterinary Resuscitation (RECOVER) Co-Chairs to arrive at treatment recommendations commensurate to quality of evidence, risk:benefit relationship, and clinical feasibility. This process was implemented using an Evidence Profile Worksheet for each question that included an introduction, consensus on science, treatment recommendations, justification for these recommendations, and important knowledge gaps. A draft of these worksheets was distributed to veterinary professionals for comment for 4 weeks prior to finalization.

SETTING

Transdisciplinary, international collaboration in university, specialty, and emergency practice.

RESULTS

Thirteen questions pertaining to hemodynamic, respiratory, and metabolic monitoring practices for identification of cardiopulmonary arrest, quality of CPR, and postcardiac arrest care were examined, and 24 treatment recommendations were formulated. Of these, 5 recommendations pertained to aspects of end-tidal CO2 (ETco2) measurement. The recommendations were founded predominantly on very low quality of evidence, with some based on expert opinion.

CONCLUSIONS

The Monitoring Domain authors continue to support initiation of chest compressions without pulse palpation. We recommend multimodal monitoring of patients at risk of cardiopulmonary arrest, at risk of re-arrest, or under general anesthesia. This report highlights the utility of ETco2 monitoring to verify correct intubation, identify return of spontaneous circulation, evaluate quality of CPR, and guide basic life support measures. Treatment recommendations further suggest intra-arrest evaluation of electrolytes (ie, potassium and calcium), as these may inform outcome-relevant interventions.

Post Cardiac Arrest Care in the Cardiac Intensive Care Unit

PURPOSE OF REVIEW

Cardiac arrests constitute a leading cause of mortality in the adult population and cardiologists are often tasked with the management of patients following cardiac arrest either as a consultant or primary provider in the cardiac intensive care unit. Familiarity with evidence-based practice for post-cardiac arrest care is a requisite for optimizing outcomes in this highly morbid group. This review will highlight important concepts necessary to managing these patients.

RECENT FINDINGS

Emerging evidence has further elucidated optimal care of post-arrest patients including timing for routine coronary angiography, utility of therapeutic hypothermia, permissive hypercapnia, and empiric aspiration pneumonia treatment. The complicated state of multi-organ failure following cardiac arrest needs to be carefully optimized by the clinician to prevent further neurologic injury and promote systemic recovery. Future studies should be aimed at understanding if these findings extend to specific patient populations, especially those at the highest risk for poor outcomes.

High incidence of acute kidney injury in extracorporeal resuscitation, Leading to poor prognosis

Background

Extracorporeal membrane oxygenation (ECMO) patients have a high incidence of acute kidney injury (AKI). Extracorporeal cardiopulmonary resuscitation (ECPR) patients are more likely to develop AKI than ECMO patients because of serious injury during cardiac arrest (CA).

Objectives

This study aims to assess the occurrence and outcomes of AKI in ECPR and ECMO, and to identify specific risk factors and clinical implications of AKI in ECPR.

Methods

This is a retrospective observational study from a single tertiary care hospital in Gwangju, Korea. Adults (≥18 years) who received ECMO with cardiac etiology in the emergency and inpatient departments from January 2015 to December 2021 were included. The patients (n = 169) were divided into two groups, ECPR and ECMO without CA, and the occurrence of AKI was investigated. The primary outcome of the study was in-hospital mortality, and the secondary outcomes were six-month cerebral performance category (CPC) and AKI during hospitalization.

Results

The incidence of AKI was significantly higher with ECPR (67.5 %) than with ECMO without CA (38.4 %). ECPR was statistically significant for Expire (adjusted OR (aOR) 2.45, 95 % CI 1.28-4.66) and Poor CPC (2.59, 1.32-5.09). AKI was also statistically significant for Expire (6.69, 3.37-13.29) and Poor CPC (5.45, 2.73-10.88). AKI was the determining factor for the outcomes of ECPR (p = 0.01).

Conclusions

ECPR patients are more likely to develop AKI than ECMO without CA patients. In ECPR patients, AKI leads to poor outcomes. Therefore, clinicians should be careful not to develop AKI in ECPR patients.

Kidney-specific biomarkers for predicting acute kidney injury following cardiac arrest

AIM

To evaluate the performance of kidney-specific biomarkers (neutrophil gelatinase-associated lipocalin (NGAL), kidney injury molecule-1 (KIM-1), and cystatin-C) in early detection of acute kidney injury (AKI) following cardiac arrest (CA) when compared to serum creatinine.

METHODS

Adult CA patients who had kidney-specific biomarkers of AKI collected within 12 h of return of spontaneous circulation (ROSC) were included. The association between renal biomarker levels post-ROSC and the development of KDIGO stage III AKI within 7 days of enrollment were assessed as well as their predictive value of future AKI development, neurological outcomes, and survival to discharge.

RESULTS

Of 153 patients, 54 (35%) developed stage III AKI within 7 days, and 98 (64%) died prior to hospital discharge. Patients who developed stage III AKI, compared to those who did not, had higher median levels of creatinine, NGAL, and cystatin-C (p < 0.001 for all). There was no statistically significant difference in KIM-1 between groups. No biomarker outperformed creatinine in the ability to predict stage III AKI, neurological outcomes, or survival outcomes (p > 0.05 for all). However, NGAL, cystatin-C, and creatinine all performed better than KIM-1 in their ability to predict AKI development (p < 0.01 for all).

CONCLUSION

In post-CA patients, creatinine, NGAL, and cystatin-C (but not KIM-1) measured shortly after ROSC were higher in patients who subsequently developed AKI. No biomarker was statistically superior to creatinine on its own for predicting the development of post-arrest AKI.

The role of targeted temperature management in 30-day hospital readmissions in cardiac arrest survivors: A national population-based study

Background

Targeted temperature management (TTM) implementation following resuscitation from cardiac arrest is controversial. Although prior studies have shown that TTM improves neurological outcomes and mortality, less is known about the rates or causes of readmission in cardiac arrest survivors within 30 days. We aimed to determine whether the implementation of TTM improves all-cause 30-day unplanned readmission rates in cardiac arrest survivors.

Methods

Using the Nationwide Readmissions Database, we identified 353,379 adult cardiac arrest index hospitalizations and discharges using the International Classification of Diseases, 9th and 10th codes. The primary outcome was 30-day all-cause unplanned readmissions following cardiac arrest discharge. Secondary outcomes included 30-day readmission rates and reasons, including impacts on other organ systems.

Results

Of 353,379 discharges for cardiac arrest with 30-day readmission, 9,898 (2.80%) received TTM during index hospitalization. TTM implementation was associated with lower 30-day all-cause unplanned readmission rates versus non-recipients (6.30% vs. 9.30%, p < 0.001). During index hospitalization, receiving TTM was also associated with higher rates of AKI (41.12% vs. 37.62%, p < 0.001) and AHF (20.13% vs. 17.30%, p < 0.001). We identified an association between lower rates of 30-day readmission for AKI (18.34% vs. 27.48%, p < 0.05) and trend toward lower AHF readmissions (11.32% vs. 17.97%, p = 0.05) among TTM recipients.

Conclusions

Our study highlights a possible negative association between TTM and unplanned 30-day readmission in cardiac arrest survivors, thereby potentially reducing the impact and burden of increased short-term readmission in these patients. Future randomized studies are warranted to optimize TTM use during post-arrest care.

Traumatic injuries to the renal blood vessels and in-hospital renal complications in patients with penetrating or blunt trauma

Background

Traumatic injuries to renal blood vessels (IRBV) can have significant consequences for patients, impacting their mortality, morbidity, and quality of life.

Objective

This study aimed to compare trauma types and injury characteristics, vital signs, and outcomes in patients with and without IRBV (nIRBV) and examine whether IRBV and pre-existing renal dysfunction affected the likelihood of in-hospital renal complications (iHRC).

Materials and Methods

After identifying penetrating and blunt trauma victims with IRBV in the National Trauma Data Bank, patient demographics, injury-related variables, treatment outcomes, and deaths under care were analyzed and compared.

Results

Of the 994,184 trauma victims, 610 (0.6%) experienced IRBV. Victims in the IRBV group (IRBVG) had a significantly higher frequency of penetrating injuries (19.5% vs. 9.2%, P < 0.001) and higher injury severity score (ISS ≥25, 61.5% vs. 6.7%). Most injuries in both groups were unintentional, although a higher frequency of assault was noted in the IRBVG. The incidence of iHRC was higher in the IRBVG (6.6%) than in the nIRBVG (0.4%; P < 0.001). The IRBV {OR = 3.5 [95% CI = (2.4-5.0)]}, preexisting renal disorders {OR = 2.5 [95% CI = (2.1-2.9)]}, and in-hospital cardiac arrest {OR = 8.6 [95% CI = (7.7-9.5)]} were found to be among the factors associated with a higher risk of iHRC.

Conclusions

IRBV and pre-existing renal disorders considerably increased the risk of developing iHRC. Due to the long- and short-term consequences of associated cardiovascular, renal, and hemodynamic complications, victims of IRBV require specialized renal management and close monitoring.

Changes of antioxidant enzymes in the kidney after cardiac arrest in the rat model

Globally, cardiac arrest (CA) is a leading cause of death and disability. Asphyxial CA (ACA)-induced kidney damage is a crucial factor in reducing the survival rate. The purpose of this study was to investigate the role of antioxidant enzymes in histopathological renal damage in an ACA rat model at different time points. A total of 88 rats were divided into five groups and exposed to ACA except for the sham group. To evaluate glomerular function and oxidative stress, serum levels of blood urea nitrogen (BUN) and creatinine (Crtn) and malondialdehyde (MDA) levels in renal tissues were measured. To determine histopathological damage, hematoxylin and eosin staining, periodic acid-Schiff staining, and Masson's trichrome staining were performed. Expression levels of antioxidant enzymes including superoxide dismutase-1 (SOD-1), superoxide dismutase-2 (SOD-2), catalase (CAT), and glutathione peroxidase (GPx) were measured by immunohistochemistry (IHC). Survival rate of the experimental rats was reduced to 80% at 6 h, 55% at 12 h, 42.9% at 1 day, and 33% at 2 days after return of spontaneous circulation. Levels of BUN, Crtn, and MDA started to increase significantly in the early period of CA induction. Renal histopathological damage increased markedly from 6 h until two days post-CA. Additionally, expression levels of antioxidant enzymes were significantly decreased at 6 h, 12 h, 1 day, and 2 days after CA. CA-induced oxidative stress and decreased levels of antioxidant enzymes (SOD-1, SOD-2, CAT, GPx) from 6 h to two days could be possible mediators of severe renal tissue damage and increased mortality rate.

Elevated Initial Serum Phosphate Levels Predict Higher Mortality and Impaired Neurological Outcome in Cardiac Arrest Patients with Return of Spontaneous Circulation

Purpose: Although a moderate proportion of cardiac arrest (CA) patients achieve a return of spontaneous circulation (ROSC), few survive to discharge, mostly with poor neurological development. As serum phosphate levels were described as elevated after cardiopulmonary resuscitation (CPR), we asked whether these elevations would predict a higher risk of mortality and impaired neurological outcome in CA patients following ROSC. Methods: Initial serum phosphate levels, survival, and neurologic status at discharge of 488 non-traumatic CA patients treated at a single German hospital after achieving ROSC were analyzed. The cut-off value of phosphate for mortality prediction was determined using the receiver operator characteristic (ROC) curve, and patients were divided accordingly for comparison. Results were validated by analyzing phosphate levels in a multi-centric cohort containing 3299 CA patients from the eICU database of the United States. Results: In the German cohort, ROC analysis showed a 90% specificity for phosphate levels >2.7 mmol/L to predict mortality (AUC: 0.76, p < 0.0001), and phosphate level elevations were associated with higher in-hospital mortality (crude odds ratio 3.04, 95% CI 2.32 to 4.08). Patients with initial phosphate levels >2.7 mmol/L had significantly higher mortality in both analyzed collectives (p < 0.0001). Similarly, patients from the German cohort who initially had higher phosphate levels also showed a higher proportion of impaired neurological status at discharge and morphological signs of brain injury. Conclusions: In CA patients following ROSC, initial serum phosphate levels >2.7 mmol/L predict higher mortality and impaired neurological outcome. Our data suggests that phosphate determination might improve the preciseness of the overall and neurologic prognostication in patients after CPR following ROSC.

Urine Output and Mortality in Patients Resuscitated from out of Hospital Cardiac Arrest

BACKGROUND

Limited data exist regarding urine output (UO) as a prognostic marker in out-of-hospital-cardiac-arrest (OHCA) survivors undergoing targeted temperature management (TTM).

METHODS

We included 247 comatose adult patients who underwent TTM after OHCA between 2007 and 2017, excluding patients with end-stage renal disease. Three groups were defined based on mean hourly UO during the first 24 h: Group 1 (<0.5 mL/kg/h, n = 73), Group 2 (0.5-1 mL/kg/h, n = 81) and Group 3 (>1 mL/kg/h, n = 93). Serum creatinine was used to classify acute kidney injury (AKI). The primary and secondary outcomes respectively were in-hospital mortality and favorable neurological outcome at hospital discharge (modified Rankin Scale [mRS]<3).

RESULTS

In-hospital mortality decreased incrementally as UO increased (adjusted OR 0.9 per 0.1 mL/kg/h higher; p = 0.002). UO < 0.5 mL/kg/h was strongly associated with higher in-hospital mortality (adjusted OR 4.2 [1.6-10.8], p = 0.003) and less favorable neurological outcomes (adjusted OR 0.4 [0.2-0.8], p = 0.007). Even among patients without AKI, lower UO portended higher mortality (40% vs 15% vs 9% for UO groups 1, 2, and 3 respectively, p < 0.001).

CONCLUSION

Higher UO is incrementally associated with lower in-hospital mortality and better neurological outcomes. Oliguria may be a more sensitive early prognostic marker than creatinine-based AKI after OHCA.

Assessing the Global Impact on the Mouse Kidney After Traumatic Brain Injury: A Transcriptomic Study

Purpose

In this study, we use animal models combined with bioinformatics strategies to investigate the potential changes in overall renal transcriptional expression after traumatic brain injury.

Methods

Microarray analysis was performed after kidney acquisition using unilateral controlled cortical impact as the primary mouse TBI model. Multi-oriented gene set enrichment analysis was performed for differentially expressed genes.

Results

The results showed that TBI affected the gene set associated with mitochondria function in kidney cells, and a negative enrichment of gene sets associated with immune cell migration and epidermal development was also observed. Analysis of the disease phenotype gene set revealed that differential expression of mitochondria-related genes was associated with lactate metabolism. Alternatively, activation and adhesion of immune cells associated with the complement system may promote autoinflammation in kidney tissue. The simulated immune cell infiltration analysis showed an increase in the proportion of activated memory CD4 T cells and a decrease in the proportion of resting memory CD4 T cells, suggesting that activated memory CD4 T cell infiltration may be involved in the inflammation of renal tissue and cause damage to renal cells, such as principal cells, mesangial cells and loops of Henle cells.

Conclusion

This study is the first to reveal the effects of brain trauma on the kidney. TBI may affect the expression of mitochondria function-related gene sets in renal cells by increasing lactate. It may also affect renal mesangial cells by inducing increased infiltration of immune cells through mechanisms related to complement system activation or autoimmune antibodies.

Kinetics of 2 different high-sensitive troponins during targeted temperature management in out-of-hospital cardiac arrest patients with acute myocardial infarction: a post hoc sub-study of a randomised clinical trial

Introduction

Short term hypothermia has been suggested to have cardio protective properties in acute myocardial infarction (AMI) by reducing infarct size as assessed by troponins. There are limited data on the kinetics of these biomarkers in comatose out-of-hospital cardiac arrest (OHCA) patients, with and without AMI, undergoing targeted temperature management (TTM) in the ICU.

Purpose

The aim of this post hoc analyses was to evaluate and compare the kinetics of two high-sensitivity cardiac troponins in OHCA survivors, with and without acute myocardial infarction (AMI), during TTM of different durations [24 h (standard) vs. 48 h (prolonged)].

Methods

In a sub-cohort (n = 114) of the international, multicentre, randomized controlled study “TTH48” we measured high-sensitive troponin T (hs-cTnT), high-sensitive troponin I (hs-cTnI) and CK-MB at the following time points: Arrival, 24 h, 48 h and 72 h from reaching the target temperature range of 33 ± 1 °C. All patients diagnosed with an AMI at the immediate coronary angiogram (CAG)—18 in the 24-h group and 25 in the 48-h group—underwent PCI with stent implantation. There were no stent thromboses.

Results

Both the hs-cTnT and hs-cTnI changes over time were highly influenced by the cause of OHCA (AMI vs. non-AMI). In contrast to non-AMI patients, both troponins remained elevated at 72 h in AMI patients. There was no difference between the two time-differentiated TTM groups in the kinetics for the two troponins.

Conclusion

In comatose OHCA survivors with an aetiology of AMI levels of both hs-cTnI and hs-cTnT remained elevated for 72 h, which is in contrast to the well-described kinetic profile of troponins in normotherm AMI patients. There was no difference in kinetic profile between the two high sensitive assays. Different duration of TTM did not influence the kinetics of the troponins.

Trial registration: Clinicaltrials.gov Identifier: NCT01689077, 20/09/2012.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12872-022-02778-4.

The conundrum of the complex relationship between acute kidney injury and cardiac arrhythmias

Acute kidney injury (AKI) is defined by a rapid increase in serum creatinine levels, reduced urine output, or both. Death may occur in 16%-49% of patients admitted to an intensive care unit with severe AKI. Complex arrhythmias are a potentially serious complication in AKI patients with pre-existing or AKI-induced heart damage and myocardial dysfunction, fluid overload, and especially electrolyte and acid-base disorders representing the pathogenetic mechanisms of arrhythmogenesis. Cardiac arrhythmias, in turn, increase the risk of poor renal outcomes, including AKI. Arrhythmic risk in AKI patients receiving kidney replacement treatment may be reduced by modifying dialysis/replacement fluid composition. The most common arrhythmia observed in AKI patients is atrial fibrillation. Severe hyperkalemia, sometimes combined with hypocalcemia, causes severe bradyarrhythmias in this clinical setting. Although the likelihood of life-threatening ventricular arrhythmias is reportedly low, the combination of cardiac ischemia and specific electrolyte or acid-base abnormalities may increase this risk, particularly in AKI patients who require kidney replacement treatment. The purpose of this review is to summarize the available epidemiological, pathophysiological, and prognostic evidence aiming to clarify the complex relationships between AKI and cardiac arrhythmias.

Predisposing Factors and Neurologic Outcomes of Patients with Elevated Serum Amylase and/or Lipase after Out-of-Hospital Cardiac Arrest: A Retrospective Cohort Study

This study investigated the patient outcomes, incidence, and predisposing factors of elevated pancreatic enzyme levels after OHCA. We conducted a retrospective cohort study of patients treated with targeted temperature management (TTM) after out-of-hospital cardiac arrest (OHCA). Elevation of pancreatic enzyme levels was defined as serum amylase or lipase levels that were at least three times the upper limit of normal. The factors associated with elevated pancreatic enzyme levels and their association with neurologic outcomes and mortality 28 days after OHCA were analyzed. Among the 355 patients, 166 (46.8%) patients developed elevated pancreatic enzyme levels. In the multivariable analysis (odds ratio, 95% confidence interval), initial shockable rhythm (0.62, 0.39−0.98, p = 0.04), time from collapse to return of spontaneous circulation (1.02, 1.01−1.04, p < 0.001), and history of coronary artery disease (1.7, 1.01−2.87, p = 0.046) were associated with elevated pancreatic enzyme levels. After adjusting for confounding factors, elevated pancreatic enzyme levels were associated with neurologic outcomes (5.44, 3.35−8.83, p < 0.001) and mortality (3.74, 2.39−5.86, p < 0.001). Increased pancreatic enzyme levels are common in patients treated with TTM after OHCA and are associated with unfavorable neurologic outcomes and mortality at 28 days after OHCA.

The influence of timing of coronary angiography on acute kidney injury in out-of-hospital cardiac arrest patients: a retrospective cohort study

BACKGROUND

Acute kidney injury (AKI) is a frequent complication in cardiac arrest survivors and associated with adverse outcome. It remains unclear whether the incidence of AKI increases after the post-cardiac arrest contrast administration for coronary angiography and whether this depends on timing of angiography. Aim of this study was to investigate whether early angiography is associated with increased development of AKI compared to deferred angiography in out-of-hospital cardiac arrest (OHCA) survivors.

METHODS

In this retrospective multicenter cohort study, we investigated whether early angiography (within 2 h) after OHCA was non-inferior to deferred angiography regarding the development of AKI. We used an absolute difference of 5% as the non-inferiority margin. Primary non-inferiority analysis was done by calculating the risk difference with its 90% confidence interval (CI) using a generalized linear model for a binary outcome. As a sensitivity analysis, we repeated the primary analysis using propensity score matching. A multivariable model was built to identify predictors of acute kidney injury.

RESULTS

A total of 2375 patients were included from 2009 until 2018, of which 1148 patients were treated with early coronary angiography and 1227 patients with delayed or no angiography. In the early angiography group 18.5% of patients developed AKI after OHCA and 24.1% in the deferred angiography group. Risk difference was - 3.7% with 90% CI ranging from - 6.7 to - 0.7%, indicating non-inferiority of early angiography. The sensitivity analysis using propensity score matching showed accordant results, but no longer non-inferiority of early angiography. The factors time to return of spontaneous circulation (odds ratio [OR] 1.12, 95% CI 1.06-1.19, p < 0.001), the (not) use of angiotensin-converting enzyme inhibitor or angiotensin II receptor blocker (OR 0.20, 95% CI 0.04-0.91, p = 0.04) and baseline creatinine (OR 1.05, 95% CI 1.03-1.07, p < 0.001) were found to be independently associated with the development of AKI.

CONCLUSIONS

Although AKI occurred in approximately 20% of OHCA patients, we found that early angiography was not associated with a higher AKI incidence than a deferred angiography strategy. The present results implicate that it is safe to perform early coronary angiography with respect to the risk of developing AKI after OHCA.

Effect of therapeutic hypothermia against renal injury in a rat model of asphyxial cardiac arrest: Α focus on the survival rate, pathophysiology and antioxidant enzymes

Although multi-organ dysfunction is associated with the survival rate following cardiac arrest (CA), the majority of studies to date have focused on hearts and brains, and few studies have considered renal failure. The objective of the present study, therefore, was to examine the effects of therapeutic hypothermia on the survival rate, pathophysiology and antioxidant enzymes in rat kidneys following asphyxial CA. Rats were sacrificed one day following CA. The survival rate, which was estimated using Kaplan-Meier analysis, was 42.9% one day following CA. However, hypothermia, which was induced following CA, significantly increased the survival rate (71.4%). In normothermia rats with CA, the serum blood urea nitrogen level was significantly increased one day post-CA. In addition, the serum creatinine level was significantly increased one day post-CA. However, in CA rats exposed to hypothermia, the levels of urea nitrogen and creatinine significantly decreased following CA. Histochemical staining revealed a significant temporal increase in renal injury after the normothermia group was subjected to CA. However, renal injury was significantly decreased in the hypothermia group. Immunohistochemical analysis of the kidney revealed a significant decrease in antioxidant enzymes (copper-zinc superoxide dismutase, manganese superoxide dismutase, glutathione peroxidase and catalase) with time in the normothermia group. However, in the hypothermia group, these enzymes were significantly elevated following CA. Collectively, the results revealed that renal dysfunction following asphyxial CA was strongly associated with the early survival rate and therapeutic hypothermia reduced renal injury via effective antioxidant mechanisms.

Acute kidney injury after in-hospital cardiac arrest in a predominant internal medicine and cardiology patient population: incidence, risk factors, and impact on survival

Introduction

Prognosis of survivors from cardiac arrest is generally poor. Acute kidney injury (AKI) is a common finding in these patients. In general, AKI is well characterized as a marker of adverse outcome. In-hospital cardiac arrest (IHCA) represents a special subset of cardiac arrest scenarios with differential predisposing factors and courses after the event, compared to out-of-hospital resuscitations. Data about AKI in survivors after in-hospital cardiac arrest are scarce.

Methods

In this study, we retrospectively analyzed patients after IHCA for incidence and risk factors of AKI and its prognostic impact on mortality. For inclusion in the analysis, patients had to survive at least 48 h after IHCA.

Results

A total of 238 IHCA events with successful resuscitation and survival beyond 48 h after the initial event were recorded. Of those, 89.9% were patients of internal medicine, and 10.1% of patients from surgery, neurology or other departments. In 120/238 patients (50.4%), AKI was diagnosed. In 28 patients (23.3%), transient or permanent renal replacement therapy had to be initiated. Male gender, preexisting chronic kidney disease and a non-shockable first ECG rhythm during resuscitation were significantly associated with a higher incidence of AKI in IHCA-survivors. In-hospital mortality in survivors from IHCA without AKI was 29.7%, and 60.8% in patients after IHCA who developed AKI (p < 0.01 between groups).

By multivariate analysis, AKI after IHCA persisted as an independent predictor of in-hospital mortality (HR 3.7 (95% CI 2.14–6.33, p ≤ 0.01)).

Conclusion

In this cohort of survivors from IHCA, AKI is a frequent finding, with adverse impact on outcome. Therefore, therapeutic strategies to prevent AKI in post-IHCA patients are warranted.

Acute kidney injury and cardiac arrest in the modern era: an updated systematic review and meta-analysis

Objective: Acute kidney injury (AKI) is associated with higher morbidity and mortality in cardiac arrest (CA). There are limited contemporary data on the incidence and outcomes of AKI in CA.Methods: We comprehensively searched the databases of MEDLINE, EMBASE, PUBMED, and the Cochrane from inception to November 2020. Observational studies that reported the incidence of AKI in CA survivors were included. Data from each study were combined using the random effects to calculate pooled incidence and risk ratios with 95% confidence intervals (CIs). The primary outcome was short-term mortality and secondary outcomes included long-term mortality, incidence of AKI, and use of renal replacement therapy (RRT). Subgroup and meta-regression analyses were performed to explore heterogeneity.Main results: A total of 25 observational studies comprising 8,165 patients were included. The incidence of AKI in CA survivors was 40.3% (range 32.9-47.8%). In stage 3 AKI, one-fourth of patients required RRT. AKI was associated with an increased risk of both short-term (OR 2.27 [95% CI 1.74-2.96]; p < 0.001) and long-term mortality (OR 1.51 [95% CI 1.93-3.25]; p < 0.001). Meta-regression and subgroup analyses did not suggest any effect of hypothermia on incidence of AKI.Conclusion: AKI complicates the care of 40% of CA survivors and is associated with significantly increased short- and long-term mortality.

Acute kidney injury in cardiogenic shock: A comprehensive review

Acute kidney injury (AKI) is an ominous predictor of mortality in cardiogenic shock. The present review examines the pathophysiology of AKI in cardiogenic shock (CS), summarizes the pertinent literature including the diagnostic criteria/definitions for AKI and possible role of biomarkers, and identifies risk factors and possible therapeutic interventions for AKI in CS. Our review finds that AKI is common in patients with CS and is associated with increased morbidity and mortality. Urinary biomarkers of renal tubular injury appear more sensitive for detection of AKI but have yet to be incorporated into daily practice. Emerging data would suggest vasopressor choices, mechanical circulatory support, and renal replacement therapy may have important therapeutic roles in the management of CS.

Association between acute kidney injury and mortality after successful cardiopulmonary resuscitation: a retrospective observational study

BACKGROUND AND OBJECTIVES

Acute Kidney Injury (AKI) affect mortality and morbidity in critically ill patients. There have been few studies examining the prevalence of AKI and mortality after successful cardiopulmonary resuscitation. In the present study, we investigated the association between AKI and mortality in post-cardiac arrest patients admitted to the Intensive Care Unit (ICU).

METHODS

Our retrospective analysis included 109 patients, admitted to the ICU following successful cardiopulmonary resuscitation between 2014 and 2016. We compared two scoring systems to estimate mortality.

RESULTS AND DISCUSSION

AKI were diagnosed in 46.7% (n = 51) of the patients based on the RIFLE criteria and 66.1% (n = 72) using the KDIGO. Mortality rate was significantly higher among patients with AKI diagnosed according to the RIFLE criteria (p = 0.012) and those with AKI diagnosed using KDIGO criteria (p = 0.003). Receiver Operating Characteristic (ROC) analysis showed that both scoring systems were able to successfully detect mortality (Area under the ROC curve = 0.693 for RIFLE and 0.731 for KDIGO).

CONCLUSION

AKI increases mortality and morbidity rates after cardiac arrest. Although more renal injury and mortality were detected with KDIGO, the sensitivity and specificity of both scoring systems were similar in predicting mortality in patients with Return of Spontaneous Circulation (ROSC).

A novel ultrasound-guided mouse model of sudden cardiac arrest

AIM

Mouse models of sudden cardiac arrest are limited by challenges with surgical technique and obtaining reliable venous access. To overcome this limitation, we sought to develop a simplified method in the mouse that uses ultrasound-guided injection of potassium chloride directly into the heart.

METHODS

Potassium chloride was delivered directly into the left ventricular cavity under ultrasound guidance in intubated mice, resulting in immediate asystole. Mice were resuscitated with injection of epinephrine and manual chest compressions and evaluated for survival, body temperature, cardiac function, kidney damage, and diffuse tissue injury.

RESULTS

The direct injection sudden cardiac arrest model causes rapid asystole with high surgical survival rates and short surgical duration. Sudden cardiac arrest mice with 8-min of asystole have significant cardiac dysfunction at 24 hours and high lethality within the first seven days, where after cardiac function begins to improve. Sudden cardiac arrest mice have secondary organ damage, including significant kidney injury but no significant change to neurologic function.

CONCLUSIONS

Ultrasound-guided direct injection of potassium chloride allows for rapid and reliable cardiac arrest in the mouse that mirrors human pathology without the need for intravenous access. This technique will improve investigators' ability to study the mechanisms underlying post-arrest changes in a mouse model.

Effects of early high-dose erythropoietin on acute kidney injury following cardiac arrest: exploratory post hoc analyses from an open-label randomized trial

BACKGROUND

Acute kidney injury (AKI) is frequent in patients resuscitated from cardiac arrest (CA) and may worsen outcome. Experimental data suggest a renoprotective effect by treating these patients with a high dose of erythropoietin (Epo) analogues. We aimed to evaluate the efficacy of epoetin alpha treatment on renal outcome after CA.

METHODS

We did a post hoc analysis of the Epo-ACR-02 trial, which randomized patients with a persistent coma after a witnessed out-of-hospital CA. Only patients admitted in one intensive care unit were analysed. In the intervention group, patients received five intravenous injections of Epo spaced 12 h apart during the first 48 h, started as soon as possible after resuscitation. In the control group, patients received standard care without Epo. The main endpoint was the proportion of patients with persistent AKI defined by Kidney Disease: Improving Global Outcomes criteria at Day 2. Secondary endpoints included the occurrence of AKI through Day 7, estimated glomerular filtration rate (eGFR) at Day 28, haematological indices and adverse events.

RESULTS

A total of 162 patients were included in the primary analysis (74 in the Epo group, 88 in the control group). Baseline characteristics were similar in the two groups. At Day 2, 52.8% of the patients (38/72) in the intervention group had an AKI, as compared with 54.4% of the patients (46/83) in the control group (P = 0.74). There was no significant difference between the two groups regarding the proportion of patients with AKI through Day 7. Among patients with persistent AKI at Day 2, 33% (4/12) in the intervention group had an eGFR <75 mL/min/1.73 m2 compared with 25% (3/12) in the control group at Day 28 (P = 0.99). We found no significant differences in haematological indices or adverse events.

CONCLUSION

After CA, early administration of Epo did not confer any renal protective effect as compared with standard therapy.

Outcome in Patients Resuscitated following Myocardial Infarction with Acute Kidney Injury

Background: Data on acute kidney injury (AKI) in patients with myocardial infarction (MI) who underwent percutaneous coronary intervention (PCI) after cardiac arrest are scarce. The prevalence of AKI, as classified by the Kidney Disease: Improving Global Outcomes (KDIGO) criteria; and its possible association with 30-day mortality were assessed. Methods: Data on 6387 patients with MI, 342 (5.3%) with out-of-hospital cardiac arrest or arrest immediately after admission before PCI, were retrospectively analyzed. The AKI and no-AKI groups were compared. The 30-day mortality was determined. Results: Ninety-three (27.2%) patients suffered AKI. AKI KDIGO stages 1, 2 and 3 occurred in 45 (13.2%), 8 (2.3%) and 40 (11.7%) patients, respectively. Higher mortality was found in AKI patients [56 (60.2%) vs. no-AKI patients 32 (12.9%); p<0.0001]. More patients died in the higher AKI KDIGO stages. In AKI KDIGO stages 1/2 and stage 3, 20 (37.7%) patients and 36 (90.0%) patients died, respectively compared to 32 (12.9%) no-AKI patients; p<0.0001. AKI was the strongest predictor of 30-day mortality (adjusted OR 6.98; 95% CI 3.42 to 14.23; p<0.0001). Other predictors were bleeding, cardiogenic shock, contrast volume-to-glomerular filtration rate ratio, and female sex. The adjusted OR for AKI KDIGO stages 1/2 and stage 3 were 3.68; 95% CI 1.53 to 8.32; p=0.002 and 29.10; 95% CI 8.31 to 101.88; p<0.0001, respectively. Conclusion: In patients resuscitated after MI undergoing PCI, AKI had a deleterious impact on the prognosis. A graded increase in the severity of AKI according to the KDIGO definition was associated with a progressively increased risk of 30-day mortality.

Incidence, Predictors, and Prognosis of Acute Kidney Injury Among Cardiac Arrest Survivors

BACKGROUND

Acute kidney injury (AKI) is common among cardiac arrest survivors. However, the outcomes and predictors are not well studied.

METHODS

This is a cohort study of cardiac arrest patients enrolled from January 2012 to December 2016 who were able to survive for 24 hours post-cardiopulmonary resuscitation. Patients with anuria, chronic kidney disease (stage 5), and end-stage renal disease were excluded. Acute kidney injury (stage 1) or higher was defined using Kidney Disease: Improving Global Outcomes classification. Multivariable adjusted regression models were used to compute hazard ratio (HR) for association of AKI with risk of mortality and odds ratio (OR) with risk of poor neurological outcomes after adjusting for demographics, comorbidities, and medical therapy. Multivariable logistic regression model was used to compute OR for association of various predictors with AKI.

RESULTS

Of 842 cardiac arrest survivors, 588 (69.8%) developed AKI. Among AKI patients, 69.4% died compared with 52.0% among non-AKI patients. In multivariable adjusted Cox proportional hazard model, development of AKI post-cardiac arrest was significantly associated with mortality (HR: 1.35; 95% confidence interval [CI]: 1.07-1.71, P = .01) and poor neurological outcomes defined as cerebral performance category >2 (OR: 2.27; 95% CI: 1.45-3.57, P < .001) and modified Rankin scale >3 (OR: 2.22; 95% CI: 1.43-3.45, P < .001). Postdischarge dialysis was also associated with increased risk of mortality (HR: 2.57; 95% CI: 1.57-4.23, P < .001). Use of vasopressors was strongly associated with development of AKI and continued need for postdischarge dialysis.

CONCLUSIONS

Acute kidney injury was associated with increased risk of mortality and poor neurological outcomes. There is need for further studies to prevent AKI in cardiac arrest survivors.

Subphenotypes of Cardiac Arrest Patients Admitted to Intensive Care Unit: a latent profile analysis of a large critical care database

Cardiac arrest (CA) may occur due to a variety of causes with heterogeneity in their clinical presentation and outcomes. This study aimed to identify clinical patterns or subphenotypes of CA patients admitted to the intensive care unit (ICU). The clinical and laboratory data of CA patients in a large electronic healthcare database were analyzed by latent profile analysis (LPA) to identify whether subphenotypes existed. Multivariable Logistic regression was used to assess whether mortality outcome was different between subphenotypes. A total of 1,352 CA patients fulfilled the eligibility criteria were included. The LPA identified three distinct subphenotypes: Profile 1 (13%) was characterized by evidence of significant neurological injury (low GCS). Profile 2 (15%) was characterized by multiple organ dysfunction with evidence of coagulopathy (prolonged aPTT and INR, decreased platelet count), hepatic injury (high bilirubin), circulatory shock (low mean blood pressure and elevated serum lactate); Profile 3 was the largest proportion (72%) of all CA patients without substantial derangement in major organ function. Profile 2 was associated with a significantly higher risk of death (OR: 2.09; 95% CI: 1.30 to 3.38) whilst the mortality rates of Profiles 3 was not significantly different from Profile 1 in multivariable model. LPA using routinely collected clinical data could identify three distinct subphenotypes of CA; those with multiple organ failure were associated with a significantly higher risk of mortality than other subphenotypes. LPA profiling may help researchers to identify the most appropriate subphenotypes of CA patients for testing effectiveness of a new intervention in a clinical trial.

Predictive value of plasma neutrophil gelatinase-associated lipocalin in acute charcoal-burning carbon monoxide poisoning

This study aimed to assess the feasibility of using the plasma neutrophil gelatinase-associated lipocalin (NGAL) level at the time of presentation in the emergency department (ED) to predict acute kidney injury (AKI) and the long-term neurological outcomes of acute charcoal-burning carbon monoxide (CO) poisoning. This retrospective study included 260 patients who suffered acute charcoal-burning CO poisoning. The median plasma NGAL concentration at the time of presentation in the ED after acute charcoal-burning CO poisoning was 78 (54–115) ng/ml. The NGAL level was an independent predictor of AKI development and could be used to stratify the severity of AKI. However, the area under the receiver operating characteristic curve (AUC) of the predictive model for AKI that included both the plasma NGAL level and clinical parameters was comparable to that of the predictive model including only the clinical parameters. The plasma NGAL level at the time of presentation in the ED was an independent factor predicting long-term neurological outcomes in patients who did not develop AKI. In these patients, the plasma NGAL level significantly improved the predictive accuracy of the model when used in combination with clinical parameters. In contrast, the plasma NGAL level was not associated with long-term neurological outcomes in patients who developed AKI. Measurement of the plasma NGAL level at the time ED presentation might improve the prediction of long-term neurological outcomes in patients who do not develop AKI after acute charcoal-burning CO poisoning. However, it might not offer additional benefit for AKI prediction compared to previously used markers.

Predictive performance of plasma neutrophil gelatinase-associated lipocalin for neurologic outcomes in out-of-hospital cardiac arrest patients treated with targeted temperature management: A prospective observational study

Few studies have demonstrated the prognostic potential of neutrophil gelatinase-associated lipocalin (NGAL) in post-cardiac arrest patients. This study evaluated the usefulness of plasma NGAL in predicting neurologic outcome and mortality in out-of-hospital cardiac arrest (OHCA) patients treated with targeted temperature management (TTM). A prospective observational study was conducted between October 2013 and April 2016 at a single tertiary hospital. We enrolled 75 patients treated with TTM and collected their demographic data, cardiopulmonary resuscitation-related information, data on plasma NGAL concentration, and prognostic test results. Plasma NGAL was measured at 4 hours after return of spontaneous circulation (ROSC). The primary endpoint was the neurologic outcome at discharge and the secondary outcome was 28-day mortality. Neurologic outcomes were analyzed using a stepwise multivariate logistic regression while 28-day mortality was analyzed using a stepwise Cox regression. The predictive performance of plasma NGAL for neurologic outcome was measured by the area under the receiver operating characteristic curve and the predictability of 28-day mortality was measured using Harrell C-index. We also compared the predictive performance of plasma NGAL to that of other traditional prognostic modalities for outcome variables. Thirty patients (40%) had good neurologic outcomes and 53 (70.7%) survived for more than 28 days. Plasma NGAL in patients with good neurologic outcomes was 122.7 ± 146.7 ng/ml, which was significantly lower than that in the poor neurologic outcome group (307.5 ± 269.6 ng/ml; P < .001). The probability of a poor neurologic outcome was more than 3.3-fold in the NGAL >124.3 ng/ml group (odds ratio, 3.321; 95% confidence interval [CI], 1.265-8.721]). Plasma NGAL in the survived group was significantly lower than that in the non-survived group (172.7 ± 191.6 vs 379.9 ± 297.8 ng/ml; P = .005). Plasma NGAL was significantly correlated with 28-day mortality (hazard ratio 1.003, 95% CI 1.001-1.004; P < .001). The predictive performance of plasma NGAL was not inferior to that of other prognostic modalities except electroencephalography. Plasma NGAL is valuable for predicting the neurologic outcome and 28-day mortality of patients with OHCA at an early stage after ROSC.This study was registered at ClinicalTrials.gov on November 19, 2013 (Identifier: NCT01987466).

Renal function after out-of-hospital cardiac arrest; the influence of temperature management and coronary angiography, a post hoc study of the target temperature management trial

Background

To elucidate the incidence of acute kidney injury (AKI) after out-of-hospital cardiac arrest (OHCA) and to examine the impact of target temperature management (TTM) and early coronary angiography on renal function.

Methods

Post hoc analysis of the TTM trial, a multinational randomised controlled trial comparing target temperature of 33 °C versus 36 °C in patients with return of spontaneous circulation after OHCA. The impact of TTM and early angiography (within 6 h of OHCA) versus late or no angiography on the development of AKI during the 7-day period after OHCA was analysed. AKI was defined according to modified KDIGO criteria in patients surviving beyond day 2 after OHCA.

Results

Following exclusions, 853 of 939 patients enrolled in the main trial were analysed. Unadjusted analysis showed that significantly more patients in the 33 °C group had AKI compared to the 36 °C group [211/431 (49%) versus 170/422 (40%) p = 0.01], with a worse severity (p = 0.018). After multivariable adjustment, the difference was not significant (odds ratio 0.75, 95% confidence interval 0.54–1.06, p = 0.10].

Five hundred seventeen patients underwent early coronary angiography. Although the unadjusted analysis showed less AKI and less severe AKI in patients who underwent early angiography compared to patients with late or no angiography, in adjusted analyses, early angiography was not an independent risk factor for AKI (odds ratio 0.73, 95% confidence interval 0.50–1.05, p = 0.09).

Conclusions

In OHCA survivors, TTM at 33 °C compared to management at 36 °C did not show different rates of AKI and early angiography was not associated with an increased risk of AKI.

Trial registration

NCT01020916. Registered on www.ClinicalTrials.gov 26 November 2009 (main trial).

Electronic supplementary material

The online version of this article (10.1186/s13054-019-2390-0) contains supplementary material, which is available to authorized users.

In-Hospital Survival and Neurological Recovery Among Patients Requiring Renal Replacement Therapy in Post-Cardiac Arrest Period

Objectives

Acute kidney injury (AKI) is common after cardiac arrest (CA). Few data exist on survival and neurological outcomes measured at hospital discharge of patients with severe AKI requiring renal replacement therapy (RRT) within the first 72 hours (i.e., duration of post-CA syndrome).

Methods

Single-center, prospective, observation cohort of patients with in- or out-of-hospital CA who survived to intensive care unit admission and were considered for targeted temperature management between 2010 and 2016 were reviewed. After excluding preexisting RRT history, patients with new RRT requirements within the first 72 hours after CA were included. Primary outcome of survival and secondary outcome of good neurological recovery defined as cerebral performance category score of 1 to 2, were compared between patients with and without RRT. Within 24 hours of initiating RRT, illness severity, as measured by Sequential Organ Failure Assessment score, Acute Physiology and Chronic Health Evaluation–II, and Charlson Comorbidity Index, was compared between survivors and nonsurvivors.

Results

Of 524 patients, 65 (12.4%) had new RRT requirements within 72 hours. Survival rates and good neurological recovery at discharge were comparable between RRT and non-RRT groups (19 of 65 [29%] vs. 162 of 459 [35%], P = 0.3, and 8 of 19 [42%] vs. 73 of 162 [45%], respectively). Sixty-three percent (12 of 19) of survivors requiring RRT did not need dialysis on discharge. Among patients requiring RRT, prognostic factors, including illness severity scores and indications for RRT, did not differ between survivors and nonsurvivors.

Conclusions

Patients with severe AKI requiring RRT during the post-CA syndrome period were not associated with any significant reduction in survival or poor neurological recovery, compared with those without RRT. Among those requiring RRT, none of the known prognostic factors predicted survival.

Markers of cardiogenic shock predict persistent acute kidney injury after out of hospital cardiac arrest

OBJECTIVE

Ischemia and reperfusion injury (IRI) in cardiac arrest patients after return to spontaneous circulation causes dysfunctions in multiple organs. Kidney injury is generally transient but in some patients persists and contributes both to mortality and increased resource utilisation. Ongoing shock may compound renal injury from IRI, resulting in persistent dysfunction. We tested whether cardiac dysfunction was associated with the development of persistent acute kidney injury (PAKI) in the first 72 h after cardiac arrest.

METHODS

We performed an observational retrospective study from January 2013 to April 2017. We included consecutive patients treated after out-of-hospital cardiac arrest at a single academic medical center with renal function measured and immediately and for 48 h post arrest. We also recorded each patient's pre arrest baseline creatinine, demographic and clinical characteristics. Our primary outcome of interest was PAKI, defined as acute kidney injury (AKI) on at least 2 measurements 24 h apart. We compared demographics and outcomes between patients with PAKI and those without, and used logistic regression to identify independent predictors of PAKI.

RESULTS

Of 98 consecutive patients, we excluded 24 for missing data. AKI was present in 75% of subjects on arrival. PAKI developed in 35% of patients. PAKI patients had a longer hospital length of stay (median 21 vs 11 days) and lower hospital survival (47% vs 71%). Serum lactate levels, dosage of adrenaline during resuscitation and days of dobutamine infusion strongly predicted PAKI.

CONCLUSIONS

Among patient who survive cardiac arrest, acute AKI is common and PAKI occurs in more than one third. PAKI is associated both with survival and with length of stay at the hospital. High doses of adrenaline, high serial serum lactate levels, and dose of dobutamine predict PAKI. Evaluation of the trajectory of renal function over the first few days after resuscitation can provide prognostic information about patient recovery.

Cardiopulmonary Resuscitation in Infants and Children With Cardiac Disease: A Scientific Statement From the American Heart Association

Cardiac arrest occurs at a higher rate in children with heart disease than in healthy children. Pediatric basic life support and advanced life support guidelines focus on delivering high-quality resuscitation in children with normal hearts. The complexity and variability in pediatric heart disease pose unique challenges during resuscitation. A writing group appointed by the American Heart Association reviewed the literature addressing resuscitation in children with heart disease. MEDLINE and Google Scholar databases were searched from 1966 to 2015, cross-referencing pediatric heart disease with pertinent resuscitation search terms. The American College of Cardiology/American Heart Association classification of recommendations and levels of evidence for practice guidelines were used. The recommendations in this statement concur with the critical components of the 2015 American Heart Association pediatric basic life support and pediatric advanced life support guidelines and are meant to serve as a resuscitation supplement. This statement is meant for caregivers of children with heart disease in the prehospital and in-hospital settings. Understanding the anatomy and physiology of the high-risk pediatric cardiac population will promote early recognition and treatment of decompensation to prevent cardiac arrest, increase survival from cardiac arrest by providing high-quality resuscitations, and improve outcomes with postresuscitation care.

Impact of Different Serum Potassium Levels on Postresuscitation Heart Function and Hemodynamics in Patients with Nontraumatic Out-of-Hospital Cardiac Arrest

Background

Sustained return of spontaneous circulation (ROSC) can be initially established in patients with out-of-hospital cardiac arrest (OHCA); however, the early postresuscitation hemodynamics can still be impaired by high levels of serum potassium (hyperkalemia). The impact of different potassium levels on early postresuscitation heart function has remained unclear. We aim to analyze the relationship between different levels of serum potassium and postresuscitation heart function during the early postresuscitation period (the first hour after achieving sustained ROSC).

Methods

Information on 479 nontraumatic OHCA patients with sustained ROSC was retrospectively obtained. Measures of early postresuscitation heart function (rate, blood pressure, and rhythm), hemodynamics (urine output and blood pH), and the duration of survival were analyzed in the case of different serum potassium levels (low: <3.5; normal: 3.5–5; high: >5 mmol/L).

Results

Most patients (59.9%, n = 287) had previously presented with high levels of potassium. Bradycardia, nonsinus rhythm, urine output <1 ml/kg/hr, and acidosis (pH < 7.35) were more common in patients with high levels of potassium (all p < 0.05). Compared with hyperkalemia, a normal potassium level was more likely to be associated with a normal heart rate (OR: 2.97, 95% CI: 1.74–5.08) and sinus rhythm (OR: 2.28, 95% CI: 1.45–3.58). A low level of potassium was more likely to be associated with tachycardia (OR: 3.54, 95% CI: 1.32–9.51), urine output >1 ml/kg/hr (OR: 5.35, 95% CI: 2.58–11.10), and nonacidosis (blood pH >7.35, OR: 7.74, 95% CI: 3.78–15.58). The duration of survival was shorter in patients with hyperkalemia than that in patients whose potassium levels were low or normal (p < 0.05).

Conclusion

Early postresuscitation heart function and hemodynamics were associated with the serum potassium level. A high potassium level was more likely to be associated with bradycardia, nonsinus rhythm, urine output <1 ml/kg/hr, and acidosis. More importantly, a high potassium level decreased the duration of survival.

Association of plasma neutrophil gelatinase-associated lipocalin with acute kidney injury and clinical outcome in cardiac arrest survivors depends on the time of measurement

PURPOSE

The optimal timing for measurement of neutrophil gelatinase-associated lipocalin (NGAL) level to predict acute kidney injury (AKI) and prognosis in cardiac arrest (CA) survivors has not been elucidated. We aimed to compare the diagnostic and prognostic performance of NGAL levels after return of spontaneous circulation (ROSC) and at 48 h after CA.

METHODS

We included 231 adult cardiac arrest survivors who underwent targeted temperature management between May 2013 and December 2016. The primary outcome was stage 2 and 3 AKI (high stage AKI), and the secondary outcomes were in-hospital mortality and neurologic outcome. Sixty-one (26.4%) developed high stage AKI, 50 (21.6%) died, and 152 (65.8%) had a poor neurologic outcome.

RESULTS

NGAL level at 48 h (0.876; 95% confidence interval [CI], 0.826-0.916) had a higher area under receiver operating characteristic curve than NGAL level after ROSC (0.694; 95% CI, 0.631-0.753). Both NGAL levels were independently associated with high stage AKI. NGAL level at 48 h (1.001; 95% CI, 1.000-1.002) remained a significant predictor for in-hospital mortality, while neither of the NGAL levels were independently associated with neurologic outcome.

CONCLUSIONS

NGAL at 48 h after CA seems to be a robust predictor for high stage AKI and in-hospital mortality.

Plasma Neutrophil Gelatinase-Associated Lipocalin Measured Immediately After Restoration of Spontaneous Circulation Predicts Acute Kidney Injury in Cardiac Arrest Survivors Who Underwent Therapeutic Hypothermia

Early diagnosis of acute kidney injury (AKI) after cardiac arrest (CA) is challenging. We aimed to identify the diagnostic and prognostic performance of neutrophil gelatinase-associated lipocalin (NGAL) for AKI and its clinical outcomes. A retrospective observational study, involving adult comatose CA survivors treated with therapeutic hypothermia between May 2013 and December 2016, was conducted. AKI was classified according to the guidelines of Kidney Disease Improving Global Outcomes. NGAL levels were measured after return of spontaneous circulation (ROSC). The primary outcome was development of AKI within 7 days after CA, and the secondary outcome was inhospital mortality. The study included 279 patients, of which 111 (39.8%) developed AKI and 61 (21.9%) died. Thirty-seven (33.3%) of patients in the AKI group had stage 3 AKI, and 45 (40.5%) patients received renal replacement therapy. The area under the curve of NGAL levels for diagnosing AKI was 0.725 (95% confidence interval [CI] 0.668-0.776), and NGAL levels were independently associated with the development of AKI (odds ratio [OR] 1.004; 95% CI 1.002-1.006). Nonsurvivors had significantly higher NGAL levels (221.0 ng/mL [154.0-355.5] vs. 148.5 ng/mL [97.0-232.9]; p < 0.001). The development of AKI was independently associated with mortality (OR 4.926; 95% CI 2.353-10.311); however, NGAL level was not associated with mortality (OR 1.000; 95% CI 0.999-1.001). Plasma NGAL level measured after ROSC can be an early predictor for the development of AKI after CA. The presence of AKI was associated with increased inhospital mortality.

Use of Renal Replacement Therapy in a Neonatal Foal with Postresuscitation Acute Renal Failure

A newborn foal was presented because it was unresponsive and in cardiopulmonary arrest. Aggressive cardiopulmonary cerebral resuscitation was administered to the foal, which revived the foal; however, acute renal failure developed. Fluid retention and azotemia occurred although the foal was alert and able to suckle. A 6‐hour renal replacement therapy session using hemodiafiltration and a continuous renal replacement therapy machine was administered to the foal at 3 days of age which lowered the foal's azotemia and facilitated removal of some of the excess body fluid. Despite therapy, the foal developed pulmonary edema and was euthanized. Although the foal in this case did not survive, this report highlights the possibility of developing postresuscitation complications such as acute renal failure and describes the use of renal replacement therapy using hemodiafiltration as a viable option in neonatal foals with acute kidney injury.

Correlation of Impedance Threshold Device use during cardiopulmonary resuscitation with post-cardiac arrest Acute Kidney Injury

PURPOSE

To assess whether use of Impedance Threshold Device (ITD) during cardiopulmonary resuscitation (CPR) reduces the degree of post-cardiac arrest Acute Kidney Injury (AKI), as a result of improved hemodynamics, in a porcine model of ventricular fibrillation (VF) cardiac arrest.

METHODS

After 8 min of untreated cardiac arrest, the animals were resuscitated either with active compression-decompression (ACD) CPR plus a sham ITD (control group, n=8) or with ACD-CPR plus an active ITD (ITD group, n=8). Adrenaline was administered every 4 min and electrical defibrillation was attempted every 2 min until return of spontaneous circulation (ROSC) or asystole. After ROSC the animals were monitored for 6 h under general anesthesia and then returned to their cages for a 48 h observation, before euthanasia. Two novel biomarkers, Neutrophil Gelatinase-Associated Lipocalin (NGAL) in plasma and Interleukin-18 (IL-18) in urine, were measured at 2 h, 4 h, 6 h, 24 h and 48 h post-ROSC, in order to assess the degree of AKI.

RESULTS

ROSC was observed in 7 (87.5%) animals treated with the sham valve and 8 (100%) animals treated with the active valve (P=NS). However, more than twice as many animals survived at 48 h in the ITD group (n=8, 100%) compared to the control group (n=3, 37.5%). Urine IL-18 and plasma NGAL levels were augmented post-ROSC in both groups, but they were significantly higher in the control group compared with the ITD group, at all measured time points.

CONCLUSION

Use of ITD during ACD-CPR improved hemodynamic parameters, increased 48 h survival and decreased the degree of post-cardiac arrest AKI in the resuscitated animals.

Renal Doppler and Novel Biomarkers to Assess Acute Kidney Injury in a Swine Model of Ventricular Fibrillation Cardiac Arrest

Background:

Majority of the research on cardiac arrest (CA) have focused on post-CA brain injury and myocardial dysfunction, the renal dysfunction and acute kidney injury (AKI) in other critical illnesses after CA have not been well described. This study was designed to assess AKI with renal Doppler and novel AKI biomarkers in a swine model of ventricular fibrillation cardiac arrest (VFCA).

Methods:

Thirty healthy piglets were divided into VFCA group (n = 22) and Sham group (n = 8) in a blinded manner. Mean arterial pressure, heart rate, and cardiac output were recorded continuously. Cardiac arrest (CA) was induced by programmed electric stimulation in the VFCA group, and then cardiopulmonary resuscitation was performed. Twenty piglets returned of spontaneous circulation (ROSC) and received intensive care. Blood and urine samples were collected for AKI biomarkers testing, and Color Doppler flow imaging was performed at baseline, 6 h, 12 h, and 24 h, respectively after ROSC. At ROSC 24 h, the animals were sacrificed and a semi-quantitative evaluation of pathologic kidney injury was performed.

Results:

In the VFCA group, corrected resistive index (cRI) increased from 0.47 ± 0.03 to 0.64 ± 0.06, and pulsatility index (PI) decreased from 0.82 ± 0.03 to 0.68 ± 0.04 after ROSC. Cystatin C (CysC) in both serum and urine samples increased at ROSC 6 h, but neutrophil gelatinase-associated lipocalin (NGAL) in serum increased to 5.34 ± 1.68 ng/ml at ROSC 6 h, and then decreased to 3.16 ± 0.69 ng/ml at ROSC 24 h while CysC increasing constantly. According to the renal histopathology, 18 of 20 animals suffered from kidney injury. The grade of renal injury was highly correlated with RI, cRI, NGAL, and CysC. Linear regression equation was established: Grade of renal injury = 0.002 × serum CysC + 6.489 × PI + 4.544 × cRI – 8.358 (r² = 0.698, F = 18.506, P < 0.001).

Conclusions:

AKI is common in post-CA syndrome. Renal Doppler and novel AKI biomarkers in serum and urine are of significant importance as early predictors of post-CA AKI.

The impact of extracerebral organ failure on outcome of patients after cardiac arrest: an observational study from the ICON database

Background

We used data from a large international database to assess the incidence and impact of extracerebral organ dysfunction on prognosis of patients admitted after cardiac arrest (CA).

Methods

This was a sub-analysis of the Intensive Care Over Nations (ICON) database, which contains data from all adult patients admitted to one of 730 participating intensive care units (ICUs) in 84 countries from 8–18 May 2012, except admissions for routine postoperative surveillance. For this analysis, patients admitted after CA (defined as those with “post-anoxic coma” or “cardiac arrest” as the reason for ICU admission) were included. Data were collected daily in the ICU for a maximum of 28 days; patients were followed up for outcome data until death, hospital discharge, or a maximum of 60 days in-hospital. Favorable neurological outcome was defined as alive at hospital discharge with a last available neurological Sequential Organ Failure Assessment (SOFA) subscore of 0–2.

Results

Among the 469 patients admitted after CA, 250 (53 %) had had out-of-hospital CA; 210 (45 %) patients died in the ICU and 357 (76 %) had an unfavorable neurological outcome. Non-survivors had a higher incidence of renal (43 vs. 16 %), cardiovascular (56 vs. 45 %), and respiratory (62 vs. 48 %) failure on admission and during the ICU stay than survivors (all p < 0.05). Similar results were found for patients with unfavorable vs. favorable neurological outcomes. In multivariable analysis, independent predictors of ICU mortality were renal failure on admission, high admission Simplified Acute Physiology Score (SAPS) II, high maximum serum lactate levels within the first 24 h after ICU admission, and development of sepsis. Independent predictors of unfavorable neurological outcome were mechanical ventilation on admission, high admission SAPS II score, and neurological dysfunction on admission.

Conclusions

In this multicenter cohort, extracerebral organ dysfunction was common in CA patients. Renal failure on admission was the only extracerebral organ dysfunction independently associated with higher ICU mortality.

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-016-1528-6) contains supplementary material, which is available to authorized users.

Impact of acute kidney injury on patient outcome in out-of-hospital cardiac arrest: a prospective observational study

BACKGROUND

Kidney disease after out-of-hospital cardiac arrest (OHCA) is incompletely described. We examined the occurrence of acute kidney injury (AKI) in OHCA patients and impact of AKI, with or without renal replacement therapy (RRT), on 6-month mortality and neurological outcome.

METHODS

Prospective study at Oslo University Hospital, Oslo, Norway. Adult resuscitated comatose OHCA patients treated with targeted temperature management at 33°C for 24 h were included. AKI and chronic kidney disease (CKD) were classified according to the Kidney Disease Improving Global Outcomes (KDIGO) guidelines. Main outcomes were 6-month mortality and good neurological outcome defined as Cerebral Performance Category 1-2.

RESULTS

Among 245 included patients (84% males, mean age 61 years), 11 (4%) had previously known CKD and 112 (46%) developed AKI. Overall 6-month outcome revealed that 112 (46%) died and 123 (50%) had good neurological outcome. Compared with no kidney disease, the presence of AKI was significantly associated with 6-month mortality (odds ratio (OR) 3.17, 95% confidence interval (CI) 1.95-5.43, P < 0.001) and good neurological outcome (OR 0.28, 95% CI 0.16-0.48, P < 0.001). Six-month mortality (50 vs. 61%, P = 0.401) and frequency of good neurological outcome (44 vs. 35%, P = 0.417) were not statistically different in AKI patients with or without RRT, also after excluding patients where RRT was withheld due to futility.

CONCLUSIONS

Kidney disease occurred in about half of patients successfully resuscitated from OHCA. Presence of AKI, but not RRT, was associated with unfavourable 6-month outcome.

[Multiple organ failure after spontaneous return of circulation in cardiac arrest in children]

OBJECTIVE

To assess the frequency of the multiple organ failure and the prognostic value of multiple organ failure scores in children who have recovered from an in-hospital cardiac arrest.

PATIENTS AND METHODS

A single centre, observational, and retrospective study was conducted on children between 1 month and 16 years old who suffered an in-hospital cardiac arrest and achieved return of spontaneous circulation (ROSC). In the first 24-48hours and between the fifth and the seventh day after ROSC, a record was made of the scores on paediatric severity (PRISM and PIM II) and multiple organ failure scales (PELOD and P-MODS), along with the clinical and analytical data, and including monitoring and treatment, mortality and cause of death.

RESULTS

Of the total of 41 children studied, 70.7% male were male, and the median age was 38 months. The overall mortality during admission was 41.5%, with 14.6% dying in the first 48hours, and 7.6% in the following 3 to 5 days. In the first 48hours, clinical severity and multiple organ failure scores were higher in the patients that died than in survivors (PRISM 29 vs. 21) P=.125, PIM II (26.8% vs. 9.2%) P=.02, PELOD (21 vs. 12) P=.005, and P-MODS (9 vs. 6) P=.001. Between the fifth and seventh day, the scores on the four scales were also higher in patients who died, but only those of the PELOD (20.5 vs. 11) p=.002 and P-MODS (6.5 vs. 3) P=.003 reached statistical significance.

CONCLUSIONS

Mortality in children after return of spontaneous circulation after cardiac arrest is high. The multiple organ failure after return of spontaneous circulation after cardiac arrest in children is associated with increased mortality.

Serum Neutrophil Gelatinase-Associated Lipocalin Predicts Survival After Resuscitation From Cardiac Arrest

OBJECTIVES

In the first days after cardiac arrest, accurate prognostication is challenging. Serum biomarkers are a potentially attractive adjunct for prognostication and risk stratification. Our primary objective in this exploratory study was to identify novel early serum biomarkers that predict survival after cardiac arrest earlier than currently possible.

DESIGN

Prospective, observational study.

SETTING

A single academic medical center.

SUBJECTS

Adult subjects who sustained cardiac arrest with return of spontaneous circulation.

INTERVENTION

None.

MEASUREMENTS AND MAIN RESULTS

We obtained blood samples from each subject at enrollment, 6, 12, 24, 48, and 72 hours after return of spontaneous circulation. We measured the serum levels of novel biomarkers, including neutrophil gelatinase-associated lipocalin, high-mobility group protein B1, intracellular cell adhesion molecule-1, and leptin, as well as previously characterized biomarkers, including neuron-specific enolase and S100B protein. Our primary outcome of interest was survival-to-hospital discharge. We compared biomarker concentrations at each time point between survivors and nonsurvivors and used logistic regression to test the unadjusted associations of baseline clinical characteristics and enrollment biomarker levels with survival. Finally, we constructed a series of adjusted models to explore the independent association of each enrollment biomarker level with survival. A total of 86 subjects were enrolled. Enrollment levels of high-mobility group protein B1, neutrophil gelatinase-associated lipocalin, and S100B were higher in nonsurvivors than survivors. Enrollment leptin, neuron-specific enolase, and intracellular cell adhesion molecule-1 levels did not differ between nonsurvivors and survivors. The discriminatory power of enrollment neutrophil gelatinase-associated lipocalin level was the greatest (c-statistic, 0.78 [95% CI, 0.66-0.90]) and remained stable across all time points. In our adjusted models, enrollment neutrophil gelatinase-associated lipocalin level was independently associated with survival even after controlling for the development of acute kidney injury, and its addition to clinical models improved overall predictive accuracy.

CONCLUSIONS

Serum neutrophil gelatinase-associated lipocalin levels are strongly predictive of survival-to-hospital discharge after cardiac arrest.

Hypoxic hepatitis after out-of-hospital cardiac arrest: Incidence, determinants and prognosis

AIM

Hypoxic hepatitis (HH) may complicate the course of resuscitated out-of-hospital cardiac arrest (OHCA) patients admitted in intensive care unit (ICU). Aims of this study were to assess the prevalence of HH, and to describe the factors associated with HH occurrence and outcome.

METHODS

We conducted an observational study over a 6-year period (2009-2014) in a cardiac arrest center. All non-traumatic OHCA patients admitted in the ICU after return of spontaneous circulation (ROSC) and who survived more than 24h were included. HH was defined as an elevation of alanine aminotransferase over 20 times the upper limit of normal during the first 72h after OHCA. Factors associated with HH and ICU mortality were picked up by multivariate logistic regression.

RESULTS

Among the 632 OHCA patients included in the study, HH was observed in 72 patients (11.4% (95% CI: 9.0%, 14.1%)). In multivariate analysis, time from collapse to ROSC [OR 1.02 per additional minute; 95% CI (1.00, 1.04); p=0.01], male gender [OR 0.53; 95% CI (0.29, 0.95); p=0.03] and initial shockable rhythm [OR 0.35; 95% CI (0.19, 0.65); p<0.01] were associated with HH occurrence. After adjustment for confounding factors, HH was associated with ICU mortality [OR 4.39; 95% CI (1.71, 11.26); p<0.01] and this association persisted even if occurrence of a post-CA shock was considered in the statistical model [OR 3.63; 95% CI (1.39, 9.48); p=0.01].

CONCLUSIONS

HH is not a rare complication after OHCA. This complication is mainly triggered by the duration of resuscitation and is associated with increased ICU mortality.