Monitoring of hematological and hemostatic parameters in neurocritical care patients

Decline in Hemoglobin during Hospitalization May Be Associated with Poor Outcome in Acute Stroke Patients

BACKGROUND AND PURPOSE

Anemia upon hospital admission is a known predictor of poor functional outcomes in patients with acute cerebral infarction. However, it remains unclear whether reductions in hemoglobin levels during hospitalization influence stroke outcomes. We investigated the association between in-hospital decline in hemoglobin and poor outcomes.

MATERIALS AND METHODS

We retrospectively analyzed data from 480 consecutive patients who had experienced acute cerebral infarction and presented without anemia between January 2012 and March 2015. Decline in hemoglobin was taken as the difference between hemoglobin levels upon admission and nadir hemoglobin. Poor outcome was defined as a modified Rankin Scale score 3-6. A multivariate analysis of the relationship between decline in hemoglobin and poor outcome at discharge was conducted for various patient characteristics.

RESULTS

The mean hemoglobin level at admission was 14.3 ± 1.3 g/dL, whereas the mean nadir hemoglobin value was 13.1 ± 1.9 g/dL, with a mean decline in hemoglobin of 1.3 ± 1.5 g/dL. In patients with poor outcomes, mean decline in hemoglobin was significantly reduced to 3.1 g/dL (P < .001). The optimal cutoff decline in hemoglobin required to distinguish a poor outcome was 1.5 g/dL whereas the sensitivity and specificity were 62% and 82.3%, respectively, with an area under the curve of .77 (P < .0001). A decline in hemoglobin below 1.5 g/dL was found to be an independent predictor of poor outcome (odds ratio: 2.10; confidence interval: 1.10-3.99; P = .023).

CONCLUSION

Decline in hemoglobin in patients hospitalized with acute stroke may be associated with poor outcome.

Medication History versus Point-of-Care Platelet Activity Testing in Patients with Intracerebral Hemorrhage

OBJECTIVE

We evaluated whether reduced platelet activity detected by point-of-care (POC) testing is a better predictor of hematoma expansion and poor functional outcomes in patients with intracerebral hemorrhage (ICH) than a history of antiplatelet medication exposure.

METHODS

Patients presenting with spontaneous ICH were enrolled in a prospective observational cohort study that collected demographic, clinical, laboratory, and radiographic data. We measured platelet activity using the PFA-100 (Siemens AG, Germany) and VerifyNow-ASA (Accumetrics, CA) systems on admission. We performed univariate and adjusted multivariate analyses to assess the strength of association between those measures and (1) hematoma growth at 24 hours and (2) functional outcomes measured by the modified Rankin Scale (mRS) at 3 months.

RESULTS

We identified 278 patients for analysis (mean age 65 ± 15, median ICH score 1 [interquartile range 0-2]), among whom 164 underwent initial neuroimaging within 6 hours of symptom onset. Univariate association with hematoma growth was stronger for antiplatelet medication history than POC measures, which was confirmed in multivariable models (β 3.64 [95% confidence interval [CI] 1.02-6.26], P = .007), with a larger effect size measured in the under 6-hour subgroup (β 7.20 [95% CI 3.35-11.1], P < .001). Moreover, antiplatelet medication history, but not POC measures of platelet activity, was independently associated with poor outcome at 3 months (mRS 4-6) in the under 6-hour subgroup (adjusted OR 3.6 [95% CI 1.2-11], P = .023).

CONCLUSION

A history of antiplatelet medication use better identifies patients at risk for hematoma growth and poor functional outcomes than POC measures of platelet activity after spontaneous ICH.

Management of neurologic complications of coagulopathies

Coagulopathy is common in intensive care units (ICUs). Many physiologic derangements lead to dysfunctional hemostasis; these may be either congenital or acquired. The most devastating outcome of coagulopathy in the critically ill is major bleeding, defined by transfusion requirement, hemodynamic instability, or intracranial hemorrhage. ICU coagulopathy often poses complex management dilemmas, as bleeding risk must be tempered with thrombotic potential. Coagulopathy associated with intracranial hemorrhage bears directly on prognosis and outcome. There is a paucity of high-quality evidence for the management of coagulopathies in neurocritical care; however, data derived from studies of patients with intraparenchymal hemorrhage may inform treatment decisions. Coagulopathy is often broadly defined as any derangement of hemostasis resulting in either excessive bleeding or clotting, although most typically it is defined as impaired clot formation. Abnormalities in coagulation testing without overt clinical bleeding may also be considered evidence of coagulopathy. This chapter will focus on acquired conditions, such as organ failure, pharmacologic therapies, and platelet dysfunction that are associated with defective clot formation and result in, or exacerbate, intracranial hemorrhage, specifically spontaneous intraparenchymal hemorrhage and traumatic brain injury.