The association of shock index and haemoglobin variation with postpartum haemorrhage after vaginal delivery: a prospective cohort pilot study.

INTRODUCTION: Shock index and continuous non-invasive haemoglobin monitoring (SpHb) have both been proposed for the timely recognition of postpartum haemorrhage (PPH). We sought to determine, in parallel, the association of each of shock index and SpHb with blood loss after vaginal delivery. METHODS: Sixty-six women were recruited to this prospective observational study. Shock index and SpHb were recorded postpartum for 120 min. The association between each of shock index and SpHb with quantitative blood loss (QBL) at 30, 60 and 120 min postpartum was determined using linear mixed models. Area-under-the-receiver-operator-characteristic (AUROC) curves were constructed to evaluate the diagnostic ability of shock index and SpHb to detect PPH (defined as QBL ≥1000 mL). RESULTS: Shock index trend was associated with QBL over the first 30 min (r=0.37, P=0.002), but not over 60 or 120 min. There was an association of SpHb trend with QBL over the first 30 min (P=0.06), but not over 60 min (r=-0.32, P=0.009) or 120 min (r=-0.26, P=0.03). Maximum shock index within 60 min correlated with QBL (r=0.54, P <0.001) and was a predictor of PPH (P=0.0012, AUROC 0.796). Maximum change in SpHb within 60 min negatively correlated with QBL (r=-0.4, P <0.001) and was a predictor of PPH (P=0.048, AUROC 0.761). CONCLUSIONS: The trend of shock index and its peak values are associated with blood loss after vaginal delivery and are early indicators of PPH. Negative trend of SpHb is a late sign of PPH and has a weaker association with blood loss than shock index.

Uterotonic drug usage in Canada: a snapshot of the practice in obstetric units of university-affiliated hospitals.

OBJECTIVE: The objective of this study was to determine the pattern of uterotonic drug usage in obstetric units of university-affiliated hospitals in Canada. METHODS: This was a prospective observational study conducted in the form of an electronic survey. The target group consisted of chiefs or directors of Obstetrics and Anaesthesia at university-affiliated hospitals across Canada. The survey was sent out between November 2016 and January 2017, using the program 'SurveyMonkey'. Data on institutional obstetric practices and usage of uterotonic agents were collected. RESULTS: The survey was sent to 92 obstetricians and anesthesiologists from 46 institutions, of which 33 clinicians from 24 institutions responded. About 65% of clinicians were unaware of the rate of postpartum hemorrhage in their institution. The first-line agent for vaginal deliveries was reported as oxytocin by 94% and carbetocin by 6% of physicians. For women at low-risk for postpartum hemorrhage when undergoing cesarean deliveries (CD), 66% reported oxytocin as the first-line uterotonic, while 34% reported carbetocin. For CDs at high-risk of postpartum hemorrhage, 60% of physicians reported oxytocin and 40% reported using carbetocin initially. The use of second-line uterotonics was also variable. The choice of uterotonic was mainly based on perceived efficacy and Society of Obstetricians and Gynaecologists of Canada guidelines. CONCLUSION: There is a lack of a unified approach to the use of uterotonic drugs for postpartum hemorrhage management in Canada. To improve the management of postpartum hemorrhage due to uterine atony, an evidence-based approach to usage and consensus between obstetricians and anesthesiologists is warranted.