298. Effect of non-steroidal anti-inflammatory drugs (NSAIDs) on blood pressure in the post-partum period: A randomised controlled trial

Introduction NSAIDs can cause an elevation in blood pressure (BP) in women outside of pregnancy when taken acutely and chronically. It is unclear if NSAIDs have a similar effect on BP in women with uncomplicated pregnancies. Objective Assess the effect on blood pressure (BP) of oral NSAIDs compared to placebo in healthy women following caesarean section. Methods A multicentre, prospective, stratified randomization (with minimisation), double blind parallel placebo controlled trial was undertaken in 4 Australian metropolitan hospitals. Commencing immediately post operatively after the caesarean section, women received either diclofenac orally, 50 mg three times a day with food or placebo for a maximum of 5 days. BP was measured by ambulatory BP measurement as well as ward based BP. Women with HDPs during pregnancy and unable to tolerate opioids were excluded. Data was analysed with STATAv14. Results A total of 284 women were randomised and the results of 270 women were analysed – 136 women in the placebo and 134 in the NSAID group. Women were well matched at baseline. The use of NSAIDs statistically but not clinically significantly reduced the ABPM measured systolic BP compared to placebo −2.2 mmHg (95%CI −4.4 mmHg to −0.1 mmHg; p = 0.04) over the 5 days post-partum. The diastolic BP was also lower in the NSAID group compared to placebo −1.5 mmHg (95%CI −2.8 mmHg to −0.14 mmHg; p = 0.03). No women required treatment for hypertension as assessed by usual clinical practice. Discussion NSAIDs do not elevate blood pressure after term caesarean in women with uncomplicated pregnancies.