Prognostic value of platelet count in paediatric intensive care unit

Abstract EN

Background : Thrombocytopenia is commonly observed in critically ill patients.

A low platelet count is a strong and independent predictor of an adverse outcome in critically ill patients, thereby facilitating a simple and practical risk assessment in these patients and potentially guiding the use of complex or expensive treatment strategies. Objectives : To evaluate the variation in platelet counts and the risk factors associated with thrombocytopenia and mortality in pediatric intensive care patients. Patients and Method : A prospective, observational cohort study was undertaken in the Pediatric Intensive Care Unit of Babylon Gynecology and Pediatric teaching hospital in Hilla city, Babil, Iraq over a period of 5 months from 1st May 2011 to 1st October 2011.

Besides patients' demography, source of admission, primary diagnosis, presence or absence of sepsis, bleeding, use of central venous or arterial lines and mechanical ventilation were recorded.

Laboratory data collected at admission included complete blood counts, C- reactive protein, blood urea nitrogen and serum creatinine, serum bilirubin and coagulation profile.

These were also repeated with the occurrence of thrombocytopenia.

Platelet count was performed daily for all patients. Results : The median Pediatric Intensive Care Unit stay was 4 days (range 2-98 days).

At least one episode of thrombocytopenia was seen in 58 patients (44.61 %) Mild, moderate, and severe thrombocytopenia was present in 27.69 %, 23.07 %, and 14.61 %, of patients respectively.

Sepsis, high blood urea and serum creatinin, high total serum bilirubin, and positive C-reactive protein had significant correlation with the development of thrombocytopenia.

There was a significant association between mortality and the presence of mechanical ventilation, sepsis, blood transfusion, high blood urea and serum creatinin, positive CRP, and leukocytosis.

The survivors had higher platelet counts throughout the Pediatric Intensive Care Unit stay and after an initial fall in platelet counts showed a significantly higher rise in the platelet counts in the following days than the non-survivors. Conclusions : • Thrombocytopenia is common in pediatric intensive care unit especially in patients with sepsis and coagulation defect. • Thrombocytopenic children have higher incidence of bleeding, and higher mortality. • Any drop in platelet counts even without thrombocytopenia needs an urgent and extensive evaluation. • Serial measurements of platelet counts are better predictors of pediatric intensive care outcome than one-time values. • Thrombocytopenia is common in ICUs and constitutes a simple and readily available risk marker for mortality, independent of and complementary to established severity of disease indices.

Both a low nadir platelet count and a large fall of platelet count predict a poor vital outcome in adult ICU patients. • We did not study the mechanisms that lead to decreased platelet count.

Nevertheless, we think other studies provide compelling arguments to assume that inflammation-induced platelet sequestration plays a major role.