Can heart rate predict low blood pressure during Caesarean section?
Research type
Research Study
Full title
An observational study of the association between heart rate in the early post-spinal period and the lowest arterial pressure recorded during planned Caesarean section.
IRAS ID
128102
Contact name
David W Cooper
Contact email
Sponsor organisation
South Tees Hospitals NHS Foundation Trust
Research summary
This is an observational study to investigate whether there is an inverse relationship between heart rate in the early post spinal period and the lowest arterial pressure recorded during spinal anaesthesia for Caesarean section.
Without adequate preventative measures hypotension (low blood pressure) occurs frequently during spinal anaesthesia for Caesarean section. Hypotension can cause the mother to feel faint and nauseated, and it reduces blood flow to the placenta, which can adversely affect the unborn baby.
Phenylephrine, a vasopressor agent (a drug which increases arterial pressure), is routinely given to try and prevent hypotension. Phenylephrine can reduce, but does not eliminate the risk of hypotension occurring. In an evaluation of our routine practice we observed an inverse association between heart rate in the early time period following induction of spinal anaesthesia (at 3-minutes post-spinal) and the lowest arterial pressure that occurred during spinal anaesthesia, approximately 10 minutes later, and 15 minutes later for those who developed hypotension.
The aim of this study is to investigate whether a relatively high heart rate at 3-minutes post-spinal is associated with a relatively low blood pressure during spinal anaesthesia when prophylactic phenylephrine is administered. We will also compare early post-spinal heart rate for those who develop hypotension or nausea with those that do not.
We plan to study 138 healthy women having spinal anaesthesia for planned Caesarean section, hypothesising that there is an inverse relationship between heart rate at 3-minutes post-spinal and the lowest arterial pressure recorded during anaesthesia. We will also test the hypothesis that early post-spinal heart is relatively high for those women that develop hypotension or nausea, despite prophylactic measures. If we find such an association, early post-spinal heart rate may prove to be a useful indicator that further prophylactic measures are required to prevent hypotension and nausea.
REC name
North East - Newcastle & North Tyneside 1 Research Ethics Committee
REC reference
13/NE/0168
Date of REC Opinion
17 Jun 2013
REC opinion
Favourable Opinion