A prospective comparison of invasive and non-invasive blood pressure in children undergoing cardiac catheterization
Invasive blood pressure in children undergoing cardiac catheterization
Submitted December 2023 by Dr Su May Koh
Read by 181 Journal Watch subscribers
This was a multicentre prospective observational study of 254 children aged under 16 undergoing cardiac catheterisation where paired non-invasive and invasive blood pressure measurements were compared. Three paediatric hospitals were involved and 683 paired blood pressure values were collected. The overall bias (SD) for mean arterial pressure was 7.2 (11.4) mmHg, however during periods of hypotension the bias (SD) was even greater at 15 (11.0) mmHg. The authors also interestingly commented that NIBP (non-invasive blood pressure) generally overestimates MAP (mean arterial pressure) in infants under a year of age and underestimates MAP in older children.
The study authors concluded from the study that non-invasive blood pressure measurements are unreliable in anaesthetised children during cardiac catheterisation and that invasive blood pressure should be instituted for high-risk cases.
This is an important study as accuracy of blood pressure monitoring is vital during anaesthesia especially during high-risk anaesthesia or periods of hypotension. Invasive arterial monitoring remains the gold standard but is not without its risks, so it is important for anaesthetists to be aware of the limitations of NIBP measurements. The authors also highlight the limited studies comparing NIBP and invasive BP monitoring in children under anaesthesia, hence the importance of their study.
The study included patients for cardiac catheterisation where invasive BP monitoring was planned already and this was paired with NIBP (Phillips Intellivue monitors). It is important to note that NIBP algorithms do vary between different monitors and hence this study may not be as generalisable as one might think. The study population of patients with congenital cardiac disease also makes this study less generalisable to the general paediatric population. It is important to bear in mind that often during cardiac catheterisation the patient arms are raised above the head so this may also affect NIBP measurements and potentially present a bias as well.
Take home message:
This study does highlight that anaesthetists need to be aware of the limitations of NIBP measurements particularly in high-risk patients and during periods of hypotension.