dc.contributor.advisor |
Stone, Peter |
|
dc.contributor.advisor |
Bennet, Laura |
|
dc.contributor.advisor |
Thompson, John |
|
dc.contributor.author |
Fontinha, Hanna |
|
dc.date.accessioned |
2021-03-10T20:45:28Z |
|
dc.date.available |
2021-03-10T20:45:28Z |
|
dc.date.issued |
2020 |
en |
dc.identifier.uri |
https://hdl.handle.net/2292/54631 |
|
dc.description.abstract |
New Zealand and international research has shown that there is an association between going to
sleep in the supine position in late pregnancy and an increased risk of stillbirth. Lying supine in
late pregnancy results in a significant decrease in maternal cardiac output and blood flow through
the abdominal aorta and the inferior vena cava. These changes in blood flow are partially
compensated for by an increase in blood flow through the azygos vein, but this does not fully
explain the physiological mechanisms behind maintenance of blood flow. This thesis aimed to
describe maternal cardiovascular autonomic responses while resting in different positions
throughout a normal healthy pregnancy and post-partum. This information would help to
determine normal cardiovascular autonomic activity in response to acute physiological stressors.
A cohort of pregnant women was studied longitudinally throughout their pregnancy and once postpartum.
A control group of nulligravid women was also assessed. Non-invasive cardiovascular
autonomic assessments included measurement of heart rate and blood pressure responses in the
left lateral, right lateral, and supine positions, as well as in response to a deep breathing and an
orthostatic manoeuvre. The standardised methodology used in this research as well as inclusion of
numerous recumbent positions and a nulligravid control group has contributed novel data to the
existing knowledge base.
Maternal cardiovascular autonomic responses, assessed by changes in heart rate and blood
pressure, were significantly affected by gestation. Gestational effects began in early pregnancy.
Cardiovascular autonomic responses to physiological stressors (e.g. the standing position, and the
supine position in late pregnancy) became significantly different with advancing gestation. These
changes largely resolved by 6 weeks post-partum. In addition, a sub-group of women were
identified who had an unstable heart rate pattern while standing in late pregnancy. Preliminary
analysis of these women concluded that there were statistically significant differences in blood
pressure and sample entropy between the two groups.
Further analysis of women with unstable heart rate patterns while standing in late pregnancy has
been identified as an important future direction. It is recommended that nulligravid women are
used as controls in future research. |
|
dc.publisher |
ResearchSpace@Auckland |
en |
dc.relation.ispartof |
PhD Thesis - University of Auckland |
en |
dc.relation.isreferencedby |
UoA99265331302002091 |
en |
dc.rights |
Items in ResearchSpace are protected by copyright, with all rights reserved, unless otherwise indicated. |
en |
dc.rights |
Items in ResearchSpace are protected by copyright, with all rights reserved, unless otherwise indicated. |
|
dc.rights.uri |
https://researchspace.auckland.ac.nz/docs/uoa-docs/rights.htm |
en |
dc.title |
A longitudinal study of maternal cardiovascular autonomic responses to position change during pregnancy |
|
dc.type |
Thesis |
en |
thesis.degree.discipline |
Obstetrics and Gynaecology |
|
thesis.degree.grantor |
The University of Auckland |
en |
thesis.degree.level |
Doctoral |
en |
thesis.degree.name |
PhD |
en |
dc.date.updated |
2021-03-05T03:33:00Z |
|
dc.rights.holder |
Copyright: The author |
en |
dc.rights.accessrights |
http://purl.org/eprint/accessRights/OpenAccess |
en |
dc.identifier.wikidata |
Q112952019 |
|