REPORTING OF HYPERTENSION AFTER EPIDURAL ANALGESIA DURING LABOR - EFFECT OF CHOICE OF ARM AND TIMING OF BASE-LINE BASE-LINE READINGS

We studied 20 women in labour to see how reporting 'hypotension' after obstetric epidural analgesia is affected by position of the blood pre ssure cuff and baseline definition. Blood pressure was recorded from b oth arms simultaneously while the woman was semirecumbent and then in the left lateral position Three readings were then taken after epidura l bupivacaine, one left lateral and the remainder right lateral. Befor e the epidural, blood pressure in the dependent arm in the lateral pos ition was similar to blood pressure in either arm in the semirecumbent position and an average of 10 mmHg (systolic) and 14 mmHg (diastolic) higher than blood pressure in the uppermost arm (p less than or equal to 0.00005). This difference persisted in both lateral positions as e pidural analgesia became established. Choosing different definitions o f hypotension, baselines and arm to measure blood pressure resulted in 'hypotension rates' between 0% and 75%. For blood pressure measuremen t in the lateral position, the blood pressure cuff should be placed on the dependent arm.