Lower platelet count and metastatic tumor are associated with increased risk of spontaneous bleeding in critically ill patients with cancer: An observational study

Background: Thrombocytopenia is common in critically ill patients with cancer. However, the association of platelet count with spontaneous bleeding is controversial in critically ill patients and the association with cancer-related characteristics is unknown.Methods: This observational study includes patients with active cancer and severe thrombocytopenia. A logistic regression model adjusted for confounders was used to evaluate the association of daily platelet count and cancer-related characteristics (type of cancer and presence of metastasis) with spontaneous bleeding. Confounders were identified using directed acyclic graphs.Results: We screened 5822 patients, 255 (4.4%) met eligibility criteria resulting in 1401 daily observations. Fifty-three patients (20.8%) had spontaneous bleeding during the intensive care unit stay, 64% presenting minor, and 36% major bleeding. The adjusted odds ratio (OR) for spontaneous bleeding with platelet count between 49 and 20 x 10(9)/L was 4.6 (1.1-19.6), with platelet count between 19 and 10 x 10(9)/L was 14.2 (3.1-66.2), and with platelet count below 10 x 109/L was 39.6 (6.9-228.5). The adjusted OR for spontaneous bleeding in patients with hematologic malignancies was 0.6 (0.4-1.2), and 4.3 (2.0-9.0) for patients with metastatic tumor.Conclusions: In critically ill patients with active cancer and severe thrombocytopenia, lower counts of platelets and presence of metastasis are associated with increased risk of spontaneous bleeding, while hematologic malignancy is not associated with increased risk of spontaneous bleeding.