During normal pregnancy the physiological changes that occur lead to altered haematological parameters. Changes to haematological parameters in critical illness have been investigated extensively in the non-pregnant population however there is a paucity of data in pregnancy and their significance on foetal wellbeing.
We aimed to assess if there was an association between abnormal haematological parameters in critically unwell pregnant women and foetal adverse outcomes.
We conducted a retrospective audit of patient files and electronic medical records of all pregnant and post-partum women admitted to the Intensive Care Unit (ICU) in Campbelltown Hospital from 2010-2016. Pregnant women were isolated and analysed. We examined the haemoglobin, white cell count (WCC) and platelet count by reviewing the most extreme values throughout admission, as well as change in platelet count. Abnormal parameters were defined as WCC >16x10^9/L, Haemoglobin <105g/L and platelet count <150x10^9/L or a change in platelet count of >50% throughout admission. Data was further analysed for mild (90-104g/L), moderate (80-89g/L) and severe (<80g/L) anaemia and mild (100-149x10^9/L), moderate (50-99x10^9/L) and severe (<50x10^9/L) thrombocytopenia. Adverse foetal outcomes were defined as Apgar score ≤7 at 5 minutes, perinatal death, preterm birth (<37 weeks) and intra-uterine growth restriction (IUGR). Statistical analysis was undertaken utilising chi-square and Kruskal-Wallis analysis with p<0.05 deemed significant (SPSSv25).
There were 76 pregnant women admitted to ICU. Women with a WCC >16x10^9/L were more likely to have a baby with IUGR (p=0.019). There was no statistically significant association between WCC and other foetal outcomes. The variables of anaemia, thrombocytopenia and change in platelet count did not show any statistically significant association with foetal adverse outcomes, nor did severity of anaemia or thrombocytopenia.
Women with higher WCC were noted to have IUGR. The significance of this is unknown at present but may represent a marker of maternal physiological stress. There was no association between haemoglobin and platelet count and adverse foetal outcomes.