Massive blood transfusion in relation to delivery: incidence, trends and risk factors: a population-based cohort study.

OBJECTIVE: To estimate incidence, trends over time, and risk factors for massive blood transfusions in obstetric patients. A secondary aim was to evaluate transfusion ratios in relation to massive transfusion. DESIGN: Population-based cohort. SETTING: Five hospitals, in the Stockholm County, Sweden, from 1990 to 2011. POPULATION: All women that gave birth in Stockholm county, Sweden, and who received blood transfusions postpartum between 1990 and 2011. METHODS: Data on pregnancies and deliveries from the Swedish National Medical Birth Registry was cross-linked to the Stockholm transfusion database. Massive blood transfusion was defined as the transfusion of ≥10 units of red blood cells from partus through the next day. MAIN OUTCOME MEASURES: Main primary outcome was massive blood transfusion postpartum. RESULTS: Our cohort comprised 517 874 deliveries. Massive blood transfusion occurred in 277 women, for an incidence of 5.3 per 10 000 deliveries, and increased by 30% (P < 0.001) between the first and the second half of the study period. Major risk factors apparent before delivery were abnormal placentation (odds ratio [OR] 41; 95% CI 29.3-58.1), pre-eclampsia/placental abruption (OR 4; 95% CI 2.8-5.6), and previous caesarean delivery (OR 4; 95% CI 3.1-6.0). Risk factors at time of delivery were uterine rupture, atonic uterus, and caesarean delivery (OR 38, 17, and 3, respectively). CONCLUSION: We found an increasing trend in the postpartum rate of massive transfusion. Women with abnormal placentation were found to have the highest increased risk. Improved antenatal awareness of these women at risk might improve management and reduce the rate of massive transfusion. TWEETABLE ABSTRACT: Risk of massive blood transfusion in obstetric patients increases with placental complications and prior caesarean section.

Postpartum blood transfusion and hemorrhage as independent risk factors for venous thromboembolism.

INTRODUCTION: Profuse postpartum hemorrhage (PPH) and red blood cell (RBC) transfusion have been suggested to be associated with venous thromboembolic events (VTE). However, it is not fully clear if they are independent major risk factors. METHODS: Women who gave birth in the Stockholm area between 1999 and 2002 were those studied, i.e., before the implementation of guidelines for thromboprophylaxis in pregnancy. In this population-based cohort study the Swedish Medical Birth Registry was linked to the National Discharge Registry and to the transfusion database. Cases with VTE were identified as well as the patient's transfusion history. The main outcome was an assessment of RBC transfusion and PPH as independent risk factors for postpartum thrombosis, analyzed in logistic regression models. RESULTS: Out of the 82,376 deliveries, 56 cases of postpartum VTE were identified (0.7‰). Compared to the control group, the risk of VTE increased with the number of RBC transfusions: 1 to 3 units (OR = 3.3, 95% CI 1.2-8.9) and >3 units (OR = 5.2, 95%CI 1.7-16.1), but PPH was not found to be a major risk factor (OR = 1.4, 95% CI 0.5-3.5). Surprisingly, the small group treated with plasma in addition to RBC transfusion were not at a significantly increased risk (OR = 1.8, 95% CI 0.2-14.0). Preeclampsia and placental abruption were major risk factors. CONCLUSION: We found RBC transfusion, but not PPH alone, to be an independent risk factor for postpartum VTE and propose that it should be included in the thromboprophylaxis algorithm for implementation during pregnancy.

Abnormally invasive placenta-prevalence, risk factors and antenatal suspicion: results from a large population-based pregnancy cohort study in the Nordic countries.

OBJECTIVE: The objective was to investigate prevalence, estimate risk factors, and antenatal suspicion of abnormally invasive placenta (AIP) associated with laparotomy in women in the Nordic countries. DESIGN: Population-based cohort study. SETTING AND POPULATION: A 3-year Nordic collaboration among obstetricians to identify and report on uterine rupture, peripartum hysterectomy, excessive blood loss, and AIP from 2009 to 2012 The Nordic Obstetric Surveillance Study (NOSS). METHODS: In the NOSS study, clinicians reported AIP cases from maternity wards and the data were validated against National health registries. MAIN OUTCOME MEASURES: Prevalence, risk factors, antenatal suspicion, birth complications, and risk estimations using aggregated national data. RESULTS: A total of 205 cases of AIP in association with laparotomy were identified, representing 3.4 per 10 000 deliveries. The single most important risk factor, which was reported in 49% of all cases of AIP, was placenta praevia. The risk of AIP increased seven-fold after one prior caesarean section (CS) to 56-fold after three or more CS. Prior postpartum haemorrhage was associated with six-fold increased risk of AIP (95% confidence interval 3.7-10.9). Approximately 70% of all cases were not diagnosed antepartum. Of these, 39% had prior CS and 33% had placenta praevia. CONCLUSION: Our findings indicate that a lower CS rate in the population may be the most effective way to lower the incidence of AIP. Focused ultrasound assessment of women at high risk will likely strengthen antenatal suspicion. Prior PPH is a novel risk factor associated with an increased prevalence of AIP. TWEETABLE ABSTRACT: An ultrasound assessment in women with placenta praevia or prior CS may double the awareness for AIP.

Effect of pancreatic phospholipase A2 and gastric lipase on the action of pancreatic carboxyl ester lipase against lipid substrates in vitro.

Preincubation of a triolein/phospholipid/cholesteryl oleate-emulsion in vitro with either pancreatic phospholipase A2 (PLA2) or gastric lipase (GL) resulted in hydrolysis (measured by pH-stat-titration) of cholesteryl [3H]oleate only after human pancreatic carboxyl ester lipase (CEL) was added to the system. No appreciable hydrolysis was observed when CEL was added alone. Consequently, a concerted action either of PLA2 and CEL or of GL and CEL made the substrate cholesteryl oleate available for hydrolysis by CEL. This was the case when cholesteryl oleate was solubilised in a phospholipid-stabilised triglyceride emulsion, which is the physico-chemical form in which the major part of dietary cholesteryl esters are presented to the gastro-intestinal tract of man.