The Efficacy of Low-Titer Group O Whole Blood Compared With Component Therapy in Civilian Trauma Patients: A Meta-Analysis.

OBJECTIVES: To assess if transfusion with low-titer group O whole blood (LTOWB) is associated with improved early and/or late survival compared with component blood product therapy (CT) in bleeding trauma patients. DATA SOURCES: A systematic search of PubMed, CINAHL, and Web of Science was performed from their inception through December 1, 2023. Key terms included injury, hemorrhage, bleeding, blood transfusion, and whole blood. STUDY SELECTION: All studies comparing outcomes in injured civilian adults and children who received LTOWB versus CT were included. DATA EXTRACTION: Data including author, publication year, sample size, total blood volumes, and clinical outcomes were extracted from each article and reported following the Meta-analysis Of Observational Studies in Epidemiology guidelines. Main outcomes were 24-hour (early) and combined 28-day, 30-day, and in-hospital (late) mortality rates between recipients of LTOWB versus CT, which were pooled using random-effects models. DATA SYNTHESIS: Of 1297 studies reviewed, 24 were appropriate for analysis. Total subjects numbered 58,717 of whom 5,164 received LTOWB. Eleven studies included adults-only, seven included both adults and adolescents, and six only included children. The median (interquartile range) age for patients who received LTOWB and CT was 35 years (24-39) and 35.5 years (23-39), respectively. Overall, 14 studies reported early mortality and 22 studies reported late mortality. LTOWB was associated with improved 24-hour survival (risk ratios [RRs] [95% CI] = 1.07 [1.03-1.12]) and late (RR [95% CI] = 1.05 [1.01-1.09]) survival compared with component therapy. There was no evidence of small study bias and all studies were graded as a moderate level of bias. CONCLUSIONS: These data suggest hemostatic resuscitation with LTOWB compared with CT improves early and late survival outcomes in bleeding civilian trauma patients. The majority of subjects were injured adults; multicenter randomized controlled studies in injured adults and children are underway to confirm these findings.

Trauma-Induced Coagulopathy in Children.

Trauma-induced coagulopathy (TIC) is well documented in injured children. However, many important features of pediatric hemostasis are still in development in early childhood and may impact TIC. Certain pediatric subgroups are at a higher risk. Traumatic brain injury, which occurs with a higher rate in children, and physical child abuse are known risk factors for TIC that deserve special consideration. Resuscitation of a pediatric trauma patient follows many of the same goals as in the injured adult trauma, although some key aspects of pediatric resuscitation require ongoing investigation. Venous thromboembolism occurs with higher rates in certain high-risk groups of pediatric trauma patients, although overall it is considerably less frequent in children as compared with adults.

Sex-dependent and race-dependent association of XPNPEP2 C-2399A polymorphism with angiotensin-converting enzyme inhibitor-associated angioedema.

BACKGROUND: Angioedema is a rare adverse effect of angiotensin-converting enzyme (ACE) inhibitors, which occurs more commonly in women and black Americans. Angioedema is thought to result from decreased degradation of vasoactive peptides. During ACE inhibition, bradykinin is primarily inactivated by aminopeptidase P (APP). Earlier studies have provided conflicting data with regard to serum APP activity in patients with a history of ACE inhibitor-associated angioedema. A single nucleotide polymorphism, -2399C>A (rs3788853, C-2399A), in XPNPEP2, the X-linked gene that encodes membranous APP, has been reported to associate with APP activity. OBJECTIVE: To test the hypothesis that the relationship between XPNPEP2 C-2399A genotype and APP activity or ACE inhibitor-associated angioedema is sex-dependent and race-dependent. METHODS: We compared C-2399A genotype frequencies in 169 cases with a history of ACE inhibitor-associated angioedema and 397 ACE inhibitor-exposed controls. Controls were prespecified to be 50% white, 50% black, and 50% women. Cases and controls were group matched for age and smoking. RESULTS: XPNPEP2 C-2399A genotype associated with serum APP activity in both men and women. Serum APP activity was lower in men than in women, independent of genotype. XPNPEP2 -2399 A/ genotype was associated with an increased risk of angioedema in men [odds ratio 2.17 (1.09-4.32), P=0.03] in multivariate analysis. The A/ genotype was associated with angioedema in black men (P=0.03) but not in white men. CONCLUSION: APP activity is lower in men and the XPNPEP2 C-2399A polymorphism associates with ACE inhibitor-associated angioedema in men but not women.