Thrombocytopenia and platelet transfusion in UK critical care: a multicenter observational study.

BACKGROUND: Platelet (PLT) transfusions are widely used, but few studies have described patterns of use in critical care. STUDY DESIGN AND METHODS: As part of a prospective multicenter observational study of all sequentially admitted patients to UK general intensive care units (ICUs) over 8 weeks, daily data were collected throughout admission on frequency of thrombocytopenia and use of PLT transfusions, in addition to clinical outcomes, including bleeding. RESULTS: There were 1923 admissions recruited across 29 ICUs for analysis (96.6% of all eligible admissions). The period prevalences of severe thrombocytopenia (<50 × 10(9) /L) for the entire ICU stay were 12.4% (234/1881) and 13.7% (263/1914) when the 24 hours before admission was also included. A total of 35.4% of patients who experienced severe thrombocytopenia died in the ICU. A total of 169 patients (9% of study population) received 534 units of transfused PLTs (median number of units per patient admission was 2; interquartile range, 1-3; maximum, 38). Pretransfusion PLT counts were more than 50 × 10(9) for 40% of PLT transfusions overall, and even when no clinically significant bleeding was recorded on the day of transfusion, the lowest recorded PLT count was more than 50 × 10(9) for 34% of transfusions. There was evidence of only modest increments in PLT count. CONCLUSION: Thrombocytopenia is common in critical care, but there is wide variation in PLT transfusion use. Patients commonly received PLT transfusions on days without clinically significant hemorrhage. The high prevalence of thrombocytopenia in the critically ill population and inconsistent patterns of PLT transfusions indicate the importance of improving the evidence base for PLT use.

A national study of plasma use in critical care: clinical indications, dose and effect on prothrombin time.

INTRODUCTION: Fresh frozen plasma (FFP) is widely used, but few studies have described patterns of plasma use in critical care. We carried out a multicentre study of coagulopathy in intensive care units (ICUs) and here describe overall FFP utilisation in adult critical care, the indications for transfusions, factors indicating the doses used and the effects of FFP use on coagulation. METHODS: We conducted a prospective, multicentre, observational study of all patients sequentially admitted to 29 adult UK general ICUs over 8 weeks. Daily data throughout ICU admission were collected concerning coagulation, relevant clinical outcomes (including bleeding), coagulopathy (defined as international normalised ratio (INR) >1.5, or equivalent prothrombin time (PT)), FFP and cryoprecipitate use and indications for transfusion. RESULTS: Of 1,923 admissions, 12.7% received FFP in the ICU during 404 FFP treatment episodes (1,212 FFP units). Overall, 0.63 FFP units/ICU admission were transfused (0.11 units/ICU day). Reasons for FFP transfusion were bleeding (48%), preprocedural prophylaxis (15%) and prophylaxis without planned procedure (36%). Overall, the median FFP dose was 10.8 ml kg⁻¹, but doses varied widely (first to third quartile, 7.2 to 14.4 ml kg⁻¹). Thirty-one percent of FFP treatments were to patients without PT prolongation, and 41% were to patients without recorded bleeding and only mildly deranged INR (<2.5). Higher volumes of FFP were administered when the indication was bleeding (median doses: bleeding 11.1 ml kg⁻¹, preprocedural prophylaxis 9.8 ml kg⁻¹, prophylaxis without procedure 8.9 ml kg⁻¹; P = 0.009 across groups) and when the pretransfusion INR was higher (ranging from median dose 8.9 ml kg⁻¹ at INR ≤ 1.5 to 15.7 ml kg⁻¹ at INR >3; P < 0.001 across ranges). Regression analyses suggested bleeding was the strongest predictor of higher FFP dose. Pretransfusion INR was more frequently normal when the transfusion indication was bleeding. Overall, posttransfusion corrections of INR were consistently small unless the pretransfusion INR was >2.5, but administration during bleeding was associated with greater INR corrections. CONCLUSIONS: There is wide variation in FFP use by ICU clinicians, and a high proportion of current FFP transfusions are of unproven clinical benefit. Better evidence from clinical trials could significantly alter patterns of use and modify current treatment costs.

Prevalence, management, and outcomes of critically ill patients with prothrombin time prolongation in United Kingdom intensive care units.

OBJECTIVE: Coagulopathy occurs frequently in critically ill patients, but its epidemiology, current treatment, and relation to patient outcome are poorly understood. We described the prevalence, risk factors, and treatment of prolongation of the prothrombin time in critically ill patients using the international normalized ratio to standardize data and explored its association with intensive care unit survival. DESIGN: Prospective multiple center observational cohort study. SETTING: Twenty-nine adult intensive care units in the United Kingdom. PATIENTS: All sequentially admitted patients over an 8-wk period. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Prospective daily data were collected concerning prevalence, predefined risk factors, and treatment of coagulopathy throughout intensive care unit admission. Of 1923 intensive care unit admissions, 30% developed abnormal international normalized ratio values (defined as an international normalized ratio > 1.5). Most international normalized ratio abnormalities were minor and short-lived (73% of worst international normalized ratio values 1.6-2.5). Male sex, chronic liver disease, sepsis, warfarin therapy, increments in Acute Physiology and Chronic Health Evaluation II score, severity of renal and hepatic dysfunction, and red cell transfusions were all independent risk factors for international normalized ratio abnormalities (all p < .001). In all regression models, there was a strong independent association between abnormal international normalized ratio values and greater intensive care unit mortality (p < .0001), particularly when international normalized ratio increased after intensive care unit admission. Among patients with abnormal international normalized ratios, 33% received fresh-frozen plasma transfusions during their intensive care unit stay, but the pretransfusion international normalized ratio value varied widely. Fifty-one percent of fresh-frozen plasma treatments were to nonbleeding patients and 40% to nonbleeding patients whose international normalized ratio was normal or only modestly deranged (≤ 2.5). The dose of fresh-frozen plasma administered was highly variable (median dose 10.8 mL/kg (first, third quartile 7.2, 14.4; range, 2.4-41.1 mL/kg). CONCLUSIONS: Prothrombin time prolongation is prevalent in critically ill patients and is independently associated with greater intensive care unit mortality. Wide variation in fresh-frozen plasma treatment exists suggesting clinical uncertainty regarding best practice, particularly as a prophylactic treatment.