Retrospective Study
Copyright ©The Author(s) 2019. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Crit Care Med. Feb 21, 2019; 8(2): 9-17
Published online Feb 21, 2019. doi: 10.5492/wjccm.v8.i2.9
Neutrophil-lymphocyte ratio: A prognostic tool in patients with in-hospital cardiac arrest
Vishal H Patel, Philip Vendittelli, Rajat Garg, Susan Szpunar, Thomas LaLonde, John Lee, Howard Rosman, Rajendra H Mehta, Hussein Othman
Vishal H Patel, Philip Vendittelli, Thomas LaLonde, Howard Rosman, Hussein Othman, Department of Cardiovascular Medicine, Ascension-St John Hospital and Medical Center, Detroit, MI 48236, United States
Rajat Garg, Department of Internal Medicine, Cleveland Clinic, Cleveland, OH 44915, United States
Susan Szpunar, Department of Biomedical Investigations and Research, Ascension-St John Hospital and Medical Center, Detroit, MI 48236, United States
John Lee, Department of Critical Care Medicine, Ascension-St John Hospital and Medical Center, Detroit, MI 48236, United States
Rajendra H Mehta, Duke Clinical Research Institute, Duke University Medical Center, Durham, NC 22705, United States
Author contributions: Patel VH, Lee J, Rosman H, Mehta RH contributed to study conception and design; Patel VH, Vendittelli P, Garg R, Szpunar S contributed to data acquisition, data analysis and interpretation; Patel VH, Rosman H, Mehta RH and LaLonde T contributed to editing, reviewing and final approval of the article.
Institutional review board statement: Approval obtained from Ascension-St John Hospital IRB committee.
Informed consent statement: Waiver of informed consent for human study subjects may be justifiable under certain rare and specific conditions. This retrospective review demonstrated minimal risk and as such, patients were not required to give informed consent to the study as determined by the IRB as some of the subjects may have moved, died, provided incorrect information or no longer be patients at Ascension St John Hospital and Medical center, it would be impracticable to attempt to contact them.
Conflict-of-interest statement: All authors declare no conflict of interest.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Corresponding author: Vishal H Patel, MD, MSc, Academic Fellow, Department of Cardiovascular Medicine, Ascension-St John Hospital and Medical Center, 22101 Moross Rd, 2nd Floor VEP, Cath Lab, Detroit, MI 48236, United States. vishal.patel@ascension.org
Telephone: +1-313-6095931 Fax: +1-313-4170542
Received: December 13, 2018
Peer-review started: December 13, 2018
First decision: January 5, 2019
Revised: January 24, 2019
Accepted: January 29, 2019
Article in press: January 30, 2019
Published online: February 21, 2019
Processing time: 70 Days and 9.4 Hours
Abstract
BACKGROUND

In-hospital cardiac arrest (IHCA) portends a poor prognosis and survival to discharge rate. Prognostic markers such as interleukin-6, S-100 protein and high sensitivity C reactive protein have been studied as predictors of adverse outcomes after return of spontaneous circulation (ROSC); however; these variables are not routine laboratory tests and incur additional cost making them difficult to incorporate and less attractive in assessing patient’s prognosis. The neutrophil-lymphocyte ratio (NLR) is a marker of adverse prognosis for many cardiovascular conditions and certain types of cancers and sepsis. We hypothesize that an elevated NLR is associated with poor outcomes including mortality at discharge in patients with IHCA.

AIM

To determine the prognostic significance of NLR in patients suffering IHCA who achieve ROSC.

METHODS

A retrospective study was performed on all patients who had IHCA with the advanced cardiac life support protocol administered in a large urban community United States hospital over a one-year period. Patients were divided into two groups based on their NLR value (NLR < 4.5 or NLR ≥ 4.5). This cutpoint was derived from receiving operator characteristic curve analysis (area under the curve = 0.66) and provided 73% positive predictive value, 82% sensitivity and 42% specificity for predicting in-hospital death after IHCA. The primary outcome was death or discharge at 30 d, whichever came first.

RESULTS

We reviewed 153 patients with a mean age of 66.1 ± 16.3 years; 48% were female. In-hospital mortality occurred in 65%. The median NLR in survivors was 4.9 (range 0.6-46.5) compared with 8.9 (0.28-96) in non-survivors (P = 0.001). A multivariable logistic regression model demonstrated that an NLR above 4.55 [odds ratio (OR) = 5.20, confidence interval (CI): 1.5-18.3, P = 0.01], older age (OR = 1.03, CI: 1.00-1.07, P = 0.05), and elevated serum lactate level (OR = 1.20, CI: 1.03-1.40, P = 0.02) were independent predictors of death.

CONCLUSION

An NLR ≥ 4.5 may be a useful marker of increased risk of death in patients with IHCA.

Keywords: Neutrophil-lymphocyte ratio; In-hospital cardiac arrest; Prognosis; Lactate; Asystole; Ventricular fibrillation; Pulseless electrical alternans; Pulseless ventricular tachycardia

Core tip: Patients who have an in-hospital cardiac arrest (IHCA) event often have poor prognosis and their survival to discharge rates are dismal. Despite advancements in resuscitation, including the use of target temperature management, the prognosis for these patients has not improved over the past 30 years. Markers that are inexpensive and easy to use that may provide some prognostic information after an IHCA event are needed. A neutrophil-lymphocyte ratio greater than 4.5 may be a useful prognostic tool and marker for increased risk of death in patients with IHCA. In addition, older age, elevated serum lactate level were also independent predictors of death.