Fresh frozen plasma reduces thrombin formation in newborn infants

Fresh frozen plasma transfusion in acute variceal haemorrhage: Results from a multicentre cohort study

BACKGROUND

Fresh frozen plasma (FFP) transfusion is often used in the management of acute variceal haemorrhage (AVH) despite best practice advice suggesting otherwise.

OBJECTIVE

We investigated if FFP transfusion affects clinical outcomes in AVH.

DESIGN, SETTING AND PATIENTS

We performed a retrospective cohort study of 244 consecutive, eligible patients admitted to five tertiary health care centres between 2013 and 2018 with AVH.

MAIN OUTCOME MEASUREMENTS

Multivariable regression analyses were used to study the association of FFP transfusion with mortality at 42 days (primary outcome) and failure to control bleeding at 5 days and length of stay (secondary outcomes).

RESULTS

Patients who received FFP transfusion (n = 100) had higher mean Model for End Stage Liver Disease (MELD) score and more severe variceal bleeding than those who did not received FFP transfusion (n = 144). Multivariable analysis showed that FFP transfusion was associated with increased odds of mortality at 42 days (odds ratio [OR] 9.41, 95% confidence interval [CI] 3.71-23.90). FFP transfusion was also associated with failure to control bleeding at 5 days (OR 3.87, 95% CI 1.28-11.70) and length of stay >7 days (adjusted OR 1.88, 95% CI 1.03-3.42). The independent association of FFP transfusion with mortality at 42 days persisted when the cohort was restricted to high-risk patients and in patients without active bleeding.

LIMITATIONS AND CONCLUSIONS

Fresh frozen plasma transfusion in AVH is independently associated with poor clinical outcomes. As this an observational study, there may be residual bias due to confounding; however, we demonstrate no benefit and potential harm with FFP transfusions in AVH.

Fresh frozen plasma transfusion in patients with cirrhosis and coagulopathy: Effect on conventional coagulation tests and thrombomodulin-modified thrombin generation

BACKGROUND & AIMS

The efficacy of fresh frozen plasma (FFP) transfusion in enhancing thrombin generation in patients with cirrhosis and impaired conventional coagulation tests has not been sufficiently explored. Thus, we aimed to assess the effect of FFP transfusion on thrombin generation in these patients.

METHODS

Fifty-three consecutive patients receiving a standard dose of FFP to treat bleeding and/or before invasive procedures - if international normalized ratio (INR)/prothrombin time (PT) ratio were ≥1.5 - were prospectively enrolled. The primary endpoint was the amelioration of endogenous thrombin potential (ETP) with thrombomodulin (ETP-TM) after transfusion, which corresponds to the total amount of generated thrombin. INR/PT ratio and activated partial thromboplastin time (aPTT) were also assessed before and after transfusion.

RESULTS

FFP enhanced ETP-TM by 5.7%, from 973 (731-1,258) to 1,028 (885-1,343 nM × min; p = 0.019). Before transfusion, evidence of normal or high ETP-TM was found in 94% of patients, even in those with bacterial infections. Only 1 (1.9%) patient had ETP-TM values reverting to the normal range after transfusion. Notably, no patients with low ETP-TM had bleeding. The median decrease in ETP-TM was 8.3% and the mean was 12.8% in 18 (34%) patients after transfusion (from 1,225 [1,071-1,537] to 1,124 [812-1,370] nM × min; p ≤0.0001). Similar responses to FFP transfusion were observed in patients with compensated and acute decompensated cirrhosis, acute-on-chronic liver failure, infection or shock. FFP significantly ameliorated INR and aPTT values (p <0.0001), but in a minority of patients the values were reduced to less than the cut-off point of 1.5.

CONCLUSIONS

FFP transfusion enhanced thrombin generation and ameliorated conventional coagulation tests to normal values in a limited number of patients, and slightly decreased thrombin generation in 34% of cases.

LAY SUMMARY

Transfusion of fresh frozen plasma in patients with cirrhosis only slightly improves coagulation test values in a limited number of patients and even appears to worsen them in a third of cases. Transfusion for the purpose of preventing or treating bleeding events could cause inherent risks and costs without clear benefits.

Neonatal Plasma Transfusion: An Evidence-Based Review

Several clinical scenarios for plasma transfusion are repeatedly identified in audits, including treatment of bleeding in association with laboratory evidence of coagulopathy, correction of disseminated intravascular coagulation, prevention of intraventricular hemorrhage, management of critically ill neonates (eg, during sepsis or as a volume expander), or correction of markers of prolonged coagulation in the absence of bleeding. The findings of at least one national audit of transfusion practice indicated that almost half of plasma transfusions are given to neonates with abnormal coagulation values with no evidence of active bleeding, despite the limited evidence base to support the effectiveness of this practice. Plasma transfusions to neonates should be considered in the clinical context of bleeding (eg, vitamin K dependent), disseminated intravascular coagulation, and very rare inherited deficiencies of coagulation factors. There seems to be no role for prophylactic plasma to prevent intraventricular hemorrhage or for use as a volume expander.

Fresh frozen plasma transfusion fails to influence the hemostatic balance in critically ill patients with a coagulopathy

BACKGROUND

Coagulopathy has a high prevalence in critically ill patients. An increased International Normalized Ratio (INR) is a common trigger to transfuse fresh frozen plasma (FFP), even in the absence of bleeding. Therefore, FFP is frequently administered to these patients. However, the efficacy of FFP in correcting hemostatic disorders in non-bleeding recipients has been questioned.

OBJECTIVES

To assess whether INR prolongation parallels changes in the results of other tests investigating hemostasis, and to evaluate the coagulant effects of a fixed dose of FFP in non-bleeding critically ill patients with a coagulopathy.

METHODS

Markers of coagulation, individual factor levels and levels of natural anticoagulants were measured. Also, thrombin generation and thromboelastometry (ROTEM) assays were performed before and after FFP transfusion (12 mL kg(-1) ) to 38 non-bleeding critically ill patients with an increased INR (1.5-3.0).

RESULTS

At baseline, levels of factor II, FV, FVII, protein C, protein S and antithrombin were reduced, and thrombin generation was impaired. ROTEM variables were within reference ranges, except for a prolonged INTEM clot formation time. FFP transfusion increased the levels of coagulation factors (FII, 34% [interquartile range (IQR) 26-46] before vs. 44% [IQR 38-52] after; FV, 48% [IQR 28-76] before vs. 58% [IQR 44-90] after; and FVII, 25% [IQR 16-38] before vs. 37% [IQR 28-55] after), and the levels of anticoagulant proteins. Thrombin generation was unaffected by FFP transfusion (endogenous thrombin potential, 72% [IQR 51-88] before vs. 71% [IQR 42-89] after), whereas ROTEM EXTEM clotting time and maximum clot firmness slightly improved in response to FFP.

CONCLUSION

In non-bleeding critically ill patients with a coagulopathy, FFP transfusion failed to induce a more procoagulant state.

Coordinated release of tissue factor and tissue factor pathway inhibitor in VLBW infants

AIM

Tissue factor (TF), a mediator between coagulation and inflammation, is upregulated in alveolar compartment and circulation in very low birthweight (VLBW) infants. We investigated the contribution of TF to systemic regulation of coagulation in VLBW infants.

METHODS

We measured TF, total and free tissue factor pathway inhibitor (TFPIt, TFPIf), prothrombin fragment (F1 + 2), and thrombin-antithrombin complexes (TAT) in plasma from 51 VLBW infants during their first week of life.

RESULTS

F1 + 2 in cord plasma was high (1385 pmol/mL) and decreased postnatally to 17% (p = 0.002). TAT decreased from a high cord concentration to 3% postnatally (p < 0.001). Plasma TF increased and peaked on day 3, showing no correlation with F1 + 2 or TAT. TFPIt and TFPIf increased postnatally, correlating with TF (day 1 TFPIf: R = 0.595, p < 0.001, day 3 TFPIf: R = 0.582, p < 0.001). Based on the TF/TFPIf ratio, a relative excess of plasma TF over TFPIf probably prevailed on day 3.

CONCLUSIONS

In VLBW infants plasma TF fails to associate with thrombin formation. This is partly explained by release of TFPI. Despite TFPI, the newborn VLBW infant is subjected to a substantial circulating pool of TF with potential proinflammatory effects.

Bleeding and Thrombotic Emergencies in Pediatric Cardiac Intensive Care

Children in the cardiac intensive care unit (CICU) with congenital or acquired heart disease are at risk for hematologic complications, both hemorrhage and thrombosis. The overall incidence of hematologic complications in the CICU is unknown, but risk factors and target groups have been identified where the essential physiologic balance between bleeding and clotting has been disrupted. Although the best management of life-threatening bleeding and clotting is prevention, the cardiac intensivist is often faced with managing life-threatening hematologic events involving patients from within the unit or those who present from outside. Part I of this review deals with the propensity of children with congenital and acquired heart disease to complications of both bleeding and clotting, and includes discussions of perioperative bleeding, thromboses in single-ventricle patients, clotting of Blalock-Taussig shunts and thrombotic complications of mechanical valves. Part II deals with the subject of stroke in children with heart disease. Part III reviews monitoring the effectiveness of anticoagulation and thrombolysis in the CICU. Currently available diagnostics modalities, medications and management strategies are reviewed and future directions discussed.

Solvent-detergent plasma: use in neonatal patients, in adult and paediatric patients with liver disease and in obstetric and gynaecological emergencies

The study was conducted to assess the efficacy and tolerance of solvent-detergent (SD) plasma in neonates, in obstetric and gynaecological patients and in patients with liver disease in three large hospitals in Dublin during the period 1 April 2002 (when SD plasma was introduced) through 31 October 2003. Forty-one neonates received 67 transfusions of SD plasma at a mean dose +/- standard deviation of 18.4 +/- 13.2 mL kg(-1). Thirty-one (75.6%) patients had coagulopathy without haemorrhage (either disseminated intravascular coagulopathy or other coagulopathy); a further eight (19.5%) had clinical haemorrhage (excluding intraventricular haemorrhage), which complicated a coagulopathy. Thirty-eight obstetric and gynaecological patients received 57 SD plasma transfusions at a mean dose of 15.3 +/- 7.7 mL kg(-1). Thirty-six women (94.7%) had haemorrhage with mean blood loss per patient of 3345.8 +/- 2738.1 mL. Fifteen children with liver disease received 33 SD plasma transfusions at a mean volume of 38.0 +/- 41.5 mL kg(-1) body weight. Seventeen adult patients with severe end-stage liver disease were transfused with SD plasma either following liver transplantation or prior to other invasive procedures, at a mean dose of 10.2 +/- 3.4 mL kg(-1). There were statistically significant decreases in mean activated partial thromboplastin time and prothrombin time in neonates, in obstetric and gynaecological patients and in patients with liver disease. Complete correction of coagulation parameters was not achieved in any case in the liver transplant group. No adverse reactions were observed for SD plasma infusion. Use of SD plasma in critically ill neonates, in women with obstetric and gynaecological emergencies and in patients with liver disease appears safe, and improves laboratory indices of coagulopathy.

Prothrombin and intraventricular haemorrhage

In the study by Salonvaara et al., low prothrombin activity in preterm infants was associated with intraventricular haemorrhage (IVH). The interesting research question-do preterm infants who develop IVH have underlying coagulation disturbance?-could not be answered in this study.

CONCLUSION

The association needs further investigation. The role of prothrombin in perinatal brain damage in the development of IVH and of white matter damage has to be further elucidated.

Low normal level of protein C or of antithrombin increases risk for recurrent cardiovascular events

The relationship between haemostatic factors and recurrent cardiovascular events was investigated in patients enrolled with acute coronary syndrome (acute non-Q myocardial infarction or unstable angina pectoris). One hundred and fifteen patients, aged 64 +/- 10 years, were included in the study. Haemostatic parameters [prothrombin time, activities of factor VII, factor VIII, factor X, antithrombin (AT) and protein C (PC), and concentrations of free protein S, fibrinogen, D-dimer, prothrombin fragment 1+2, and thrombin-antithrombin complex] were measured four times: within 48 h of hospitalization, at discharge (days 5-8), at 3 months and after 1 year. Screening for factor V Leiden mutation was also performed. Patients were followed for cardiovascular endpoints (new or refractory unstable angina pectoris, non-fatal myocardial infarction, stroke, or death) for an average of 555 days. Of all patients, 35 had an endpoint during the follow-up ("endpoint" group) and 80 patients did not ("no endpoint" group). Analysing the whole follow-up period, PC (P < 0.01) and AT (P < 0.01) were lower in the "endpoint" than in the "no endpoint" group. With 50% percentiles at enrollment, the odds ratio for getting an endpoint in the low (cut-off value < 100%) versus high PC group was 2.72 (95% confidence interval, 1.18-6.29; P < 0.05). Lower levels of AT (P < 0.05) and PC (P < 0.05) during the whole follow-up were associated with a shorter event-free time. In conclusion, lower PC and AT values, even within the normal range, seem to be associated with elevated risk for recurrent cardiovascular events and shorter event-free time in acute coronary syndrome patients.

A simple automatized audit system for following and managing practices of platelet and plasma transfusions in a neonatal intensive care unit

During neonatal intensive care, blood components are often used in clinical situations where both their efficacy and safety lack solid justification. A practical system to continuously analyse actual transfusion practices is a prerequisite for improvements of quality in transfusion therapy. We hypothesized that such a system would reveal inappropriate variations in clinical decision making and offer a means for staff education and quality improvement and assurance. The study consisted of three 120-152-day periods (P I, P II and P III) between January 2000 and October 2001 and involved 543 new patient admissions (141 patients with birth weight < 1501 g) and 6227 days of patient care at a single tertiary level NICU. P I was a control with no intervention, P II was after technically introducing the computer system and, the last period, P III was after presenting and discussing the results of P I and P II at a staff meeting. Upon an order of platelet or fresh frozen plasma (FFP) unit from the blood bank, a computer-based audit system compared the last platelet count or prothrombin time [expressed as percentage of normal clotting activity, prothrombin time (PT-%)] to predefined criteria. In the case of exceeding the preset thresholds, the system required additional information and recorded the pretransfusion laboratory values for later analysis. Thirty-two per cent of platelet transfusions were given with pretransfusion platelet count >49 x 10(9) L(-1), and 60% of these transfusions (19% of all platelet transfusions) could not be clinically justified in retrospective chart review. There was no significant change in this practice from P II to P III. FFP transfusions were given with significantly different pretransfusion PT-% values during P II and P III. The proportions of FFP transfusions with pretransfusion PT-% > 49% were 7.8% and 0.9% during P II and P III, respectively (P < 0.0001). In chart review, none of the FFP transfusions with pretransfusion PT-% > 49% could be justified by clinical grounds. Inappropriate transfusions of both platelets and plasma remain a significant challenge for quality assurance of neonatal intensive care. Automated recording of pretransfusion platelet count and prothrombin time reliably identified the poorly justified transfusions and thus offered a practical resource-saving tool for quality assurance of transfusion in the NICU. A significant shift towards more appropriate use of plasma was demonstrated after implementation of the audit system.