The role of drug-level monitoring among patients using direct-acting oral anticoagulant (DOAC) is unclear. We aimed to investigate its 'real-life' utilization and effect on clinical management. A review of records of patients who underwent DOAC level testing during 2013-2017. Overall, 212 patients (median age 77 years) underwent 292 DOAC measurements [apixaban (n = 147), rivaroxaban (n = 102), dabigatran (n = 43)]. Monitoring volume increased by 460% during study period. DOAC level testing was performed during routine follow-up in 51 (17.5%) cases, whereas the remaining 241 (82.5%) measurements were performed due to selected clinical circumstances, most commonly: bleeding (n = 60), perioperative status (n = 45), breakthrough thrombosis (n = 37) and renal failure (n = 35). Drug levels were within the expected range in 210 (71.9%), above the expected range in 62 (21.2%) and lower than expected range in 20 (6.8%). In multivariate analysis, older age (P = 0.005), lower glomerular filtration rate (P = 0.001) and lower body mass index (P = 0.006) were associated with DOAC levels above the expected range. Clinical decisions were affected by DOAC monitoring following most (140/241, 58.1%) measurements for which we identified an indication for testing; yet only rarely when monitoring was performed during routine follow-up (7.8%, 4/51) (P < 0.0001). While no benefit of routine DOAC monitoring was observed, drug level measurement has an important role in the management of patients in selected circumstances. Age, body weight and creatinine clearance were found to be significant predictors of drug levels. Future studies are warranted to establish associations between drug levels and outcomes, and better delineate the role of DOAC monitoring.

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Data are limited on the effects of drug interactions on direct-acting oral anticoagulant (DOAC) levels. We evaluated the effects of the use of interacting drugs on DOAC levels in patients with atrial fibrillation (AF). We reviewed data of AF patients tested for DOAC levels in 2013-2017. The primary outcomes were drug levels exceeding the expected steady-state range, and in the highest quartile. A multivariate analysis was performed to evaluate the correlation of treatment by the use of interacting drugs, CYP3A4 and P-glycoprotein (P-gp) inhibitors, with the primary outcomes. Overall, 147 patients underwent DOAC level measurement [dabigatran (n = 31), rivaroxaban (n = 29), apixaban (n = 87)]. Thirty-three (22.4%) had drug levels exceeding the expected range. Seventy-nine (53.7%) patients were treated with at least one interacting drug. In multivariate analysis, the concomitant use of interacting drugs was an independent predictor for drug levels exceeding the expected range (OR 3.3, 95% CI 1.20-9.05). The defined daily dose of the interacting drug correlated positively with DOAC levels (r = 0.29, P = 0.001). Co-treatment with interacting drugs was associated with extremely high levels of dabigatran, (OR 16.6, 95% CI 1.29-215.18) but not of the other DOAC examined. Concomitant use of interacting drugs is associated with high DOAC levels in patients with AF. Further investigation is warranted to establish the differences between specific DOAC, evaluate the effect on patient outcomes, and characterize the role of DOAC monitoring in this setting.

Objectives To examine the outcomes of planned induction of labour versus spontaneous onset of labour among women using prophylactic‐dose low‐molecular weight heparin (LMWH) therapy. Design Retrospective cohort study. Setting University hospital. Population Women receiving antepartum prophylactic LMWH therapy undergoing a trial of vaginal delivery. Methods Charts from 2018–2019 were reviewed. Main outcome measures Duration of anticoagulation interruption and eligibility to receive neuraxial anaesthesia. Results Data from 199 women were analysed; 78 (39.2%) were admitted following spontaneous onset of labour and 121 (60.8%) underwent planned induction of labour. Compared to women who underwent planned induction of labour, women who presented with spontaneous onset of labour had a shorter median admission‐to‐delivery interval (4.7 versus 29.3 hours, P < 0.001). Similarly, intervals from the last LMWH injection to delivery (25.8 versus 48.2 hours, P < 0.001) and to the first postpartum LMWH injection (41.2 versus 63.7 hours, P < 0.001) were shorter. Among those with spontaneous onset of labour, 69 (88.5%) were eligible to receive neuraxial anaesthesia. Rates of postpartum haemorrhage and blood transfusion were similar between the groups. No thrombotic events were encountered in those with spontaneous onset of labour, but four (3.3%) women who delivered following induction of labour developed a postpartum thrombotic event. Conclusion Planned induction of labour was associated with a higher risk of postpartum thrombotic events than was spontaneous onset of labour (4 of 121 [3.3%] versus 0 of 78 [0%]), presumably due to prolonged duration of anticoagulation interruption, although the difference was not statistically significant. Allowing spontaneous onset of labour was associated with comparable rates of bleeding complications, and only a low proportion (9 of 78, 11.5%) were not eligible to receive neuraxial anaesthesia. Tweetable abstract Planned induction among women using prophylactic LMWH therapy might increase the risk of thromboembolic complications.

were treated with either intravenous labetalol, intravenous hydralazine, or oral nifedipine.Results of the retrospective analysis indicated that of the 213 women included in the study, 110 women (51.6%) experienced delayed treatment (greater than 60 min), while 103 (48.4%) received treatment within 60 min. Delayed treatment of obstetric hypertensive emergency had 3.2 times the odds of presenting an initial non-severe blood pressure range verses those patients who received timely treatment (odds ratio [OR] 3.24 [95% confidence interval (CI) 1.85-5.68]; adjusted OR, 3.77 [95% CI,). Additionally, patients with delayed treatment were 2.7 times less likely to have preeclampsia symptoms at presentation (OR, 2.68 [95% CI, 1.50-4.80]; adjusted OR, 2.30 [95% CI, 1.06-4.99]), and 2.7 times more likely to experience hypertensive emergencies between 10p.m. and 6a.m (OR, 2.72 [95% CI, 1.27-5.83]; adjusted OR, 2.63 [95% CI, 1.07-6.42]). Furthermore, white race was associated with delayed treatment (OR, 1.79 [95% CI, 1.04-3.08]; adjusted OR, 2.90 [95% CI, 1.48-5.68]). Patients with delayed treatment were more likely to have a higher gestational age at presentation (36.6 ± 4 wk vs. 34.6 ± 5 wk; P < 0.001). A greater proportion of patients having delayed treatment occurred overnight.In conclusion, the study found that a majority of women with hypertensive emergencies received delayed treatment (51.6%). Findings indicated that patients who presented with higher, severe-range blood pressure were more likely to receive timely treatment. In fact, presenting with blood pressure in the non-severe range yielded the highest odds of delayed treatment. Additionally, those who received timely treatment were more likely to experience hypertensive emergencies during the day (as opposed to overnight or on weekends) and to present at a lower gestational age. Raising awareness of these biases and barriers, including through further research, could lead to improved patient outcomes.