Predictors of acute kidney injury in patients after extracorporeal cardiopulmonary resuscitation

Acute kidney injury as a prognostic predictor of in-hospital mortality and neurological outcomes in patients after extracorporeal cardiopulmonary resuscitation

INTRODUCTION

Extracorporeal cardiopulmonary resuscitation (ECPR) is increasingly being applied to patients with refractory cardiac arrest, but the survival rate to hospital discharge is only approximately 29%. Because ECPR requires intensive resources, it is important to predict outcomes. We therefore investigated the prognostic association between acute kidney injury (AKI) and ECPR to confirm the performance of AKI as a prognostic predictor of in-hospital mortality and neurological outcomes in ECPR.

METHODS

We conducted a retrospective observational study on patients undergoing ECPR for cardiac etiology at Chonnam National University Hospital from 2015 to 2021. The group diagnosed with AKI in any KDIGO category within the first 48 h after ECPR was compared to that without AKI, and the primary outcome of the study was in-hospital mortality.

RESULTS

Of 138 enrolled patients, 83 were studied. Hospital mortality occurred in 49 patients (59%), and 55 (66.3%) showed poor neurological outcomes. The AKI group displayed significantly elevated in-hospital mortality (77.8% vs 24.1%) and poor neurological outcomes (81.5% vs 37.9%) compared to the non-AKI group (p < 0.001). Regression analysis showed that AKI was associated with significantly higher rates of both in-hospital mortality (odds ratio (OR) range 10.75-12.88) and neurologic outcomes (OR range 5.9-6.22).

CONCLUSIONS

There was a significant association of AKI with both in-hospital mortality and poor neurologic outcome in patients after ECPR, and AKI can be used as an early prognostic predictor in these patients.

Treatment of Refractory Cardiac Arrest by Controlled Reperfusion of the Whole Body: A Multicenter, Prospective Observational Study

Background: Survival following cardiac arrest (CA) remains poor after conventional cardiopulmonary resuscitation (CCPR) (6-26%), and the outcomes after extracorporeal cardiopulmonary resuscitation (ECPR) are often inconsistent. Poor survival is a consequence of CA, low-flow states during CCPR, multi-organ injury, insufficient monitoring, and delayed treatment of the causative condition. We developed a new strategy to address these issues. Methods: This all-comers, multicenter, prospective observational study (69 patients with in- and out-of-hospital CA (IHCA and OHCA) after prolonged refractory CCPR) focused on extracorporeal cardiopulmonary support, comprehensive monitoring, multi-organ repair, and the potential for out-of-hospital cannulation and treatment. Result: The overall survival rate at hospital discharge was 42.0%, and a favorable neurological outcome (CPC 1+2) at 90 days was achieved for 79.3% of survivors (CPC 1+2 survival 33%). IHCA survival was very favorable (51.7%), as was CPC 1+2 survival at 90 days (41%). Survival of OHCA patients was 35% and CPC 1+2 survival at 90 days was 28%. The subgroup of OHCA patients with pre-hospital cannulation showed a superior survival rate of 57.1%. Conclusions: This new strategy focusing on repairing damage to multiple organs appears to improve outcomes after CA, and these findings should provide a sound basis for further research in this area.

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.

Extracorporeal Cardiopulmonary Resuscitation

BACKGROUND

Around the world, survival rates after cardiac arrest range between <14% for in-hospital (IHCA) and <10% for outof- hospital cardiac arrest (OHCA). This situation could potentially be improved by using extracorporeal membrane oxygenation (ECMO) during cardiopulmonary resuscitation (CPR), i.e. by extracorporeal cardiopulmonary resuscitation (ECPR).

METHODS

A selective literature search of Pubmed and Embase using the searching string ((ECMO) OR (ECLS)) AND (ECPR)) was carried out in February 2023 to prepare an up-to-date review of published trials comparing the outcomes of ECPR with those of conventional CPR.

RESULTS

Out of 573 initial results, 12 studies were included in this review, among them three randomized controlled trials comparing ECPR with CPR, involving a total of 420 patients. The survival rates for ECPR ranged from 20% to 43% for OHCA and 20% to 30.4% for IHCA. Most of the publications were associated with a high degree of bias and a low level of evidence.

CONCLUSION

ECPR can potentially improve survival rates after cardiac arrest compared to conventional CPR when used in experienced, high-volume centers in highly selected patients (young age, initial shockable rhythm, witnessed cardiac arrest, therapy-refractory high-quality CPR). No general recommendation for the use of ECPR can be issued at present.