Biochemical parameters of patients presenting for elective and urgent caesarean sections at Chris Hani Baragwanath Hospital
Date
2012-01-17
Authors
Nethathe, Gladness Dakalo
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
Introduction
Maternal volume depletion at the time of caesarean section plays a role in ma-
ternal and fetal outcome. Measuring
uid volume status currently requires
invasive monitors. It would be useful to determine biochemical measurements
which would accurately determine
uid volume status in these patients. We
investigated the di erence in biochemical parameters of participants presenting
for elective and urgent caesarean section at Chris Hani Baragwanath Hospital
and made inferences about their
uid volume status. We also sought to de-
termine whether this difference in biochemical parameters if present could be
linked to a potential difference in the intra-operative haemodynamic course as
well as fetal outcome between the two groups.
Method
This was a prospective open-label observational cross-sectional pilot study. The
sample was 54 participants, 27 elective and 27 urgent cases.
Blood and urine samples were taken at the red line. Parameters from the
blood samples were haematocrit, haemoglobin, sodium, urea, creatinine and
plasma osmolality. Parameters from the urine samples were sodium, creatinine,
osmolality and specific gravity.
Intra-operatively, all participants received a standard spinal anaesthetic. Vari-
ables measured intra-operatively were systolic, diastolic and mean arterial blood
pressure, heart rate, highest level of block achieved as well as 1 and 5 minute
Apgar scores of the newborn.
The primary outcome variable was hypotension (mean arterial drop of more
than 15% from the baseline). The secondary outcome variable were the Apgar scores of the infants.
Results
Urine specific gravity showed a trend towards statistical significance (mean,
median, standard deviation for elective, urgent): 1.01, 1.010, 0.01 and 1.02,
1.015, 0.01 p = 0:06. The other biochemical parameteres displayed higher p-
values.
The average relative blood pressure change was -11,7% (median, standard de-
viation) (-12.4, 11.1) for the elective group and -15.1% (-14.9, 15.1) for the
urgent group p = 0:36. The relative blood pressure change to end point of
study was -9.6% (-9, 12.7) for the elective group and -15.4% (-17, 17.6) for the
urgent group p = 0:17. When comparing baseline blood pressure and heart rate
measurements to the 10 minute end point measurements; 15 participants expe-
rienced hypotension in the urgent group compared to 9 in the elective group
p = 0:17. When comparing baseline blood pressure measurements to the av-
erage at 2, 4, 6, 8, and 10 minute intervals; 13 participants from the urgent
group experienced hypotension compared to 9 participants in the elective group
p = 0:40.
The average Apgar scores at 1 min were 8.89 (9,0.32) for the elective group
and 8.37 (9,0.93) for the urgent group p = 0:01.
Conclusion
This was a pilot study and as such statistical signi cance between variables was
not expected. However possible trends were identified to guide future investiga-
tions. The higher incidence rate of hypotension in the urgent group showed such
a trend towards signi cance as well as the higher urine specific
gravity in the
urgent group. We also noted that Apgar scores differed significantly between
elective and urgent cases.