This Article Full Text Free Full Text (PDF) Free All Versions of this Article: chest.06-2233v1 131/6/1735    most recent Submit a response Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in ISI Web of Science Similar articles in PubMed Alert me to new issues of the journal Add to My Personal Article Archive Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Moreau, D. Articles by Azoulay, E. Search for Related Content PubMed PubMed Citation Articles by Moreau, D. Articles by Azoulay, E.

Platelet Count Decline^*

An Early Prognostic Marker in Critically Ill Patients With Prolonged ICU Stays

Delphine Moreau, MD; Jean-François Timsit, MD, PhD; Aurélien Vesin, MS; Maité Garrouste-Orgeas, MD; Arnaud de Lassence, MD; Jean-Ralph Zahar, MD; Christophe Adrie, MD, PhD; François Vincent, MD; Yves Cohen, MD, PhD; Benoît Schlemmer, MD and Elie Azoulay, MD, PhD

^* From the Medical ICU (Drs. Moreau, Schlemmer, and Azoulay), Saint Louis Teaching Hospital, Paris, France; the Medical ICU (Drs. Timsit and Vesin), Michallon Teaching Hospital, Grenoble, France; the Medical-Surgical ICU (Dr. Garrouste-Orgeas), Saint Joseph Teaching Hospital, Paris, France; the Medical-Surgical ICU (Dr. de Lassence), Louis Mourier Teaching Hospital, Colombes, France; the Microbiology Unit (Dr. Zahar), Necker Hospital, Paris, France; the Medical ICU (Dr. Adrie), Hôpital de La Fontaine, Saint Denis, France; and the Medical-Surgical ICU (Dr. Vincent) and Service de Réanimation (Dr. Cohen), Avicenne Teaching Hospital, Bobigny, France. Deceased. A complete list of members of the Outcomerea Study Group is located in the ^Appendix.

Correspondence to: Elie Azoulay, MD, PhD, Medical ICU, Saint Louis Teaching Hospital, 1 Ave Claude Vellefaux, 75010 Paris, France; e-mail: elie.azoulay{at}outcomerea.org

Abstract

Background: Thrombocytopenia is common in ICU patients. The objective of this study was to evaluate possible links between declining platelet counts early in the ICU stay and survival.

Methods: All patients who were admitted to the ICU for at least 5 days and had no thrombocytopenia at the time of admission were included in the study. A multivariable logistic regression model, with hospital mortality as the outcome variable, was built.

Results: We included 1,077 patients in the study. At ICU admission, the median platelet count was not significantly different in survivors (256 x 10⁹ cells/L; interquartile range [IQR], 206 to 330 x 10⁹ cells/L) and nonsurvivors (262 x 10⁹ cells/L; 211 to 351 x 10⁹ cells/L). Median simplified acute physiology scores II (SAPS II) at ICU admission was worse in nonsurvivors than in survivors (50 [IQR, 37 to 63] vs 37 [IQR, 27 to 48], respectively; p < 0.0001), as was the mean (± SD) sequential organ failure assessment (SOFA) score on day 3 (6.3 ± 3.24 vs 4 ± 2.8, respectively; p < 0.0001). Absolute platelet counts were lowest on day 4, but differed significantly between survivors and nonsurvivors only on day 7. Conversely, any percentage decline in platelet counts from 10 to 60% on day 4 was significantly associated with mortality. By multivariable analysis, a 30% decline in platelet count independently predicted death (odds ratio, 1.54; 95% confidence interval, 1.12 to 2.14; p = 0.008), in addition to increasing or stable SOFA scores from ICU admission to day 4, older age, male gender, ICU admission for coma, worse SAPS II score at ICU admission, transfer from another ward, and comorbidity.

Conclusion: In patients who spend > 5 days in the ICU and have normal platelet counts at ICU admission, a decline in platelet counts provides prognostic information. This parameter deserves to be included in new scoring systems.

Key Words: ICU • mortality • outcome • platelet count • severity score