Variability in the Use of Platelet Transfusion in Patients with Intracerebral Hemorrhage: Observations from the Ethnic/Racial Variations of Intracerebral Hemorrhage Study.

BACKGROUND: We examined platelet transfusion (PTx) in the Ethnic/Racial Variations of Intracerebral Hemorrhage (ERICH) study, hypothesizing that rates of PTx would vary among hospitals and depend on whether patients were on an antiplatelet therapy or underwent intracerebral hemorrhage (ICH) surgical treatment. METHODS: The ERICH study is a prospective observational study evaluating risk factors for ICH among whites, blacks, and Hispanics. We identified factors associated with PTx, examined practice patterns of PTx across the United States, and explored the association of PTx with mortality and poor outcome (modified Rankin Scale score 4-6). RESULTS: Nineteen centers enrolled 2572 ICH cases; 11.7% received PTx. Factors significantly associated with PTx were antiplatelet use before onset (odds ratio [OR], 5.02; 95% confidence interval [CI], 3.81-6.61, P < .0001), thrombocytopenia (OR, 13.53; 95% CI, 8.43-21.72, P < .0001), and ventriculostomy placement (OR, 1.85; 95% CI, 1.36-2.52, P < .0001). Blacks were less likely (OR, .57; 95% CI, .41-0.80) to receive PTx. Among patients who received PTx, 42.4% were not on an antiplatelet therapy before onset. Twenty-three percent of patients on antiplatelet therapy received PTx, but percentages varied from 0% to 71% across centers. There was no difference in mortality or poor outcome at 3 months between patients receiving PTx and those who did not. CONCLUSIONS: The frequency of PTx for ICH varies across academic centers. Thrombocytopenia, antiplatelet use, vascular risk factors, and ventriculostomy placement were associated with PTx. PTx was not associated with improved outcomes. We anticipate reduced PTx use over time given recent clinical trial data suggesting its use could be harmful; however, the issue of whether surgical management warrants PTx remains.

Thrombelastography does not predict clinical response to rtPA for acute ischemic stroke.

Thrombelastography (TEG) measures coagulation in venous blood. We hypothesized that TEG, by reflecting clot subtype and ex vivo fibrinolysis, might predict fibrinolytic response to tPA as reflected by rapid clinical improvement or hemorrhagic transformation of the infarct. 171 acute ischemic stroke patients treated with tPA were prospectively enrolled. Venous blood for TEG was drawn before and 10 min after tPA bolus. We measured rapid clinical improvement (RCI = 8 point improvement on NIHSS or total NIHSS of 0, 1 at 36 h), Hemorrhagic transformation (HT = any blood on imaging within 36 h), and hyperdense middle cerebral artery sign (HDMCA = biomarker for erythrocyte-rich clot). Multivariable regression models compared TEG parameters after adjusting for potential confounders. No differences in pre- or post-tPA TEG were found between patients with or without RCI. Also, there was no correlation between TEG and HDMCA. Clotting was slightly prolonged in patients with HT (p = 0.046). We failed to find a robust association between TEG and clinical response to tPA. It is likely that arterial clot lysis is determined by factors unrelated to coagulation status as measured by TEG in the venous circulation. It is unlikely that TEG will be useful to predict clinical response to tPA, but may help predict bleeding.

Clot Strength as Measured by Thrombelastography Correlates with Platelet Reactivity in Stroke Patients.

OBJECTIVE: Platelet reactivity may be important in the management of patients with stroke. However, degree of platelet reactivity has not been correlated with Thrombelastography (TEG(®)) parameters in stroke. We sought to detect a correlation between TEG(®) values and clot platelet reactivity in ex vivo clots of stroke patients. METHODS: We collected venous blood from 40 patients with stroke. TEG(®) measurements were carried out and residual clots were fixed in 10% formalin immediately following completion of TEG(®). The formalin specimens were embedded in paraffin blocks, cut at 4 micrometers, and stained with CD 61 (immunohistochemical stain used to detect platelets) with appropriate controls. Under light microscopy, three pathologists blinded to TEG(®) results independently graded CD61 intensity (how aggregated/intense the CD61 stained) into a low and high group, as a proposed measurement representing the platelet reactivity of the clot. We compared pre-tPA-TEG(®) values among groups with different CD 61 intensities. RESULTS: After adjusting for confounding factors, we found statistically significant correlation between CD61 staining and several TEG(®) parameters (Delta and CD61 staining intensity (p=0.047); Angle and CD61 staining intensity grade (p=0.04); and G and CD61 staining intensity grade (p=0.04)). CONCLUSIONS: Clot strength on TEG(®) as measured by Delta, Angle, and G correlates with a clot with greater platelet reactivity.

Thrombelastography detects possible coagulation disturbance in patients with intracerebral hemorrhage with hematoma enlargement.

BACKGROUND AND PURPOSE: Intracerebral hemorrhage (ICH) has high morbidity, and hematoma enlargement (HE) causes worse outcome. Thrombelastography (TEG) measures the dynamics of clot formation and dissolution, and might be useful for assessing bleeding risk. We used TEG to detect changes in clotting in patients with and without HE after ICH. METHODS: This prospective study included 64 patients with spontaneous ICH admitted from 2009 to 2013. TEG was performed within 6 hours of symptom onset and after 36 hours. Brain imaging was obtained at baseline and at 36±12 hours, and HE was defined as total volume increase>6 cc or >33%. TEG was also obtained from 57 controls. RESULTS: Compared with controls, patients with ICH demonstrated faster and stronger clot formation; shorter R and delta (P<0.0001) at baseline; and higher MA and G (P<0.0001) at 36 hours; 11 patients had HE. After controlling for potential confounders, baseline K and delta were longer in HE+ compared with HE- patients, indicating that HE+ patients had slower clot formation (P<0.05). TEG was not different between HE+ and HE- patients at 36 hours. CONCLUSIONS: TEG may detect important coagulation changes in patients with ICH. Clotting may be faster and stronger in immediate response to ICH, and a less robust response may be associated with HE. These findings deserve further investigation.

Iodinated contrast does not alter clotting dynamics in acute ischemic stroke as measured by thromboelastography.

BACKGROUND AND PURPOSE: Iodinated contrast agents used for computed tomography angiography (CTA) may alter fibrin fiber characteristics and decrease fibrinolysis by tissue plasminogen activator (tPA). Thromboelastography (TEG) measures the dynamics of coagulation and correlates with thrombolysis in acute ischemic stroke patients. We hypothesized that receiving CTA before tPA will not impair thrombolysis as measured by TEG. METHODS: Acute ischemic stroke patients receiving 0.9 mg/kg tPA <4.5 hours of symptom onset were prospectively enrolled. For CTA, 350 mg/dL of iohexol or 320 mg/dL of iodixanol at a dose of 2.2 mL/kg was administered. TEG was measured before tPA and 10 minutes after tPA bolus. CTA timing was left to the discretion of the treating physician. RESULTS: Of 136 acute ischemic stroke patients who received tPA, 47 had CTA before tPA bolus, and 42 had either CTA after tPA and post-tPA TEG draw or no CTA (noncontrast group). Median change in clot lysis (LY30) after tPA was 95.3% in the contrast group versus 95.0% in the noncontrast group (P=0.74). Thus, tPA-induced thrombolysis did not differ between contrast and noncontrast groups. Additionally, there was no effect of contrast on any pre-tPA TEG value. CONCLUSIONS: Our data do not support an effect of iodinated contrast agents on clot formation or tPA activity.

Prevalencia de Esclerosis Múltiple en Lima - Perú / Prevalence of Multiple Sclerosis in Lima - Perú

La Esclerosis Múltiple (EM) es la principal enfermedad desmielinizante a nivel mundial. La epidemiología señala una mayor prevalencia de esta entidad en áreas alejadas de la línea ecuatorial. Existen algunos estudios de prevalencia en Latinoamérica, ninguno publicado en el Perú. Objetivo: Determinar la prevalencia de Esclerosis Múltiple en Lima, Perú. Material y métodos: Se utilizó el método captura recaptura para estimar la prevalencia de EM en Lima en 4 centros de pacientes con Esclerosis Múltiple de la ciudad: Hypnos Instituto del Sueño en la Clínica San Felipe, elHospital Nacional Cayetano Heredia, la Clínica El Golf y la Asociación ôEsclerosis Múltiple Perúõ (ESMUP). Resultados: Se calculó la prevalencia de EM en 7,69 x 100 000 habitantes (intervalo de confianza al 95 por ciento 7,09 a 8,30). Conclusiones: La prevalencia estimada de EM, para la ciudad de Lima, se encuentra en rango medio bajo.

Multiple Sclerosis (ME) is the main demyelinating disease over the world. The epidemiology shows a higher prevalence of this entity in areas away from the equatorial line. There are some prevalence studies published in Latinamerica, but no previous information reported in Peru. Objective: To determine the prevalence of ME in Lima, Peru. Material and Methods: Capture-recapture method was used to estimate the prevalence of ME in Lima, four centres of patients with ME in the city were evaluated: Hypnos Sleep Institute in ôSan Felipeõ Clinic, Hospital Nacional Cayetano Heredia, ôEl Golfõ Clinic and ôEsclerosis Múltiple del Perúõ Society (ESMUP). Results: The calculated prevalence of ME was 7.69 x 100 000 habitants (Confidence Interval at 95 per cent: 7.09 to 8.30). Conclusions: The estimated prevalence of ME, for Lima, is about the medium low range.

Identificación de síntomas relacionados al Síndrome de Apnea Obstructiva del sueño en historias clínicas de pacientes con eventos vasculares agudos / Identification of obstructive sleep apnea syndrome related symptoms in clinical charts of patients with an acute vascular event

El síndrome de apnea obstructiva del sueño (SAOS) se caracteriza por ronquidos, pausas en la respiración y somnolencia diurna excesiva entre los síntomas más relevantes. Se ha demostrado una asociación con incremento de riesgo vascular en pacientes con SAOS. Objetivo: Evaluar si el personal médico busca síntomas relacionados al SAOS en pacientes con un cuadro cerebrovascular o síndrome coronario agudo, en los servicios de Medicina del Hospital Nacional Cayetano Heredia en Lima, Perú, desde Setiembre del 2003 hasta Setiembre del 2004. Materiales y métodos: Se planteó un estudio observacional restrospectivo. Se revisaron historias clínicas de 291 pacientes con diagnóstico al ingreso de accidente cerebrovascular, ataque isquémico transitorio o síndrome coronario agudo, buscando información sobre síntomas relacionados al SAOS, incluyendo evaluación por especialidades y epicrisis, detallando los evaluadores que recogieron los datos. Resultados: En la evaluación de 291 pacientes participaron 1122 evaluadores, 0.98 por ciento de ellos consignó descartar el SAOS, que correspondió a 9 pacientes. En sólo 1 paciente se sugirió realizar un estudio de poliosomnografía para corroborar el diagnóstico, sin ofrecerse ninguna opción terapéutica. Del total de pacientes, en el 6.87 por ciento se indagó por ronquidos durante el sueño, 28,52 por ciento por somnolencia y 0,68 por ciento por episodios de apneas durante el sueño. Conclusiones: No se realiza una adecuada búsqueda del SAOS en pacientes con un evento cardiovascular o cerebrovascular agudo. En los pocos pacientes en los que se sospecha esta patología no existe seguimiento clínico ni tampoco se ofrece opción diagnóstica ni terapéutica alguna.