Blood Pressure in Critically Ill Children: Exploratory Analyses of Concurrent Invasive and Noninvasive Measurements

Blood pressure monitoring following kidney transplantation in children: a comparison of invasive and noninvasive measurements using Doppler as a benchmark technique

BACKGROUND

Blood pressure (BP) monitoring following pediatric kidney transplantation is essential for optimizing graft perfusion. Differences between invasive BP and noninvasive BP (NIBP) measurements are sometimes considerable. We aimed to assess agreement between invasive BP and NIBP in pediatric patients after kidney transplantation and compare with measurements obtained by systolic Doppler with manual sphygmomanometer as a reference technique.

METHODS

A prospective, observational cohort study, of children aged 18 years or younger, admitted immediately following kidney transplantation to the pediatric intensive care unit of a tertiary, university-affiliated medical center, between May 2019 and June 2021.

RESULTS

Eighty-two paired simultaneous measurements of invasive BP, NIBP, and Doppler BP in 18 patients were compared. Patients were significantly hypertensive, with mean systolic NIBP above the 95th percentile (96 ± 6%). Systolic invasive BP measurements were significantly higher than NIBP (149 ± 20 vs. 136 ± 15 mmHg, p < 0.001). Substantial differences (≥ 20 mmHg) were found in 23% (95% CI 15-34%). Similar disagreement was found between systolic invasive and Doppler BP (150 ± 23 and 137 ± 17 mmHg, respectively, p < 0.001). In contrast, systolic NIBP was in good agreement with Doppler BP (135 ± 17 and 138 ± 18, respectively, p = 0.27). A moderate to strong correlation was found between higher systolic invasive BP and the difference to systolic Doppler BP (Spearman's ρ = 0.63, p < 0.001).

CONCLUSIONS

In children immediately following kidney transplantation, clinically significant disagreement was found between invasive and noninvasive BP measurements. Invasive BP values were significantly higher than those obtained by Doppler. Better agreement was found between NIBP and Doppler. These issues should be considered when interpreting BP measurements in this sensitive patient population. A higher resolution version of the Graphical abstract is available as Supplementary information.

Comparison of Blood Pressure Measurements by Currently Available Multiparameter Monitors and Mercury Column Sphygmomanometer in Patients Admitted in Pediatric Intensive Care Unit

Background

The multiparameter monitor (MPM) is replacing mercury column sphygmomanometers (MCS) in acute care settings. However, data on the former's accuracy in critically ill children are scarce and mostly extrapolated from adults. We compared non-invasive blood pressure (NIBP) measurements by MPMs with MCS in pediatric intensive care unit (PICU).

Patients

Adequately sedated and hemodynamically stabilized children (age, 1-144 months) were prospectively enrolled.

Materials and methods

Three NIBP measurements were obtained from MCS (Diamond®, India) and MPM (Intellivue MX800® or Ultraview SL®) in rapid succession in the upper limb resting in supine position. Respective three measurements were averaged to obtain a paired set of NIBP readings, one each from MCS and MPM. Such readings were obtained thrice a day. NIBP readings were then compared, and agreement was assessed.

Results

From 39 children [median age (IQR), 30 (10-72) months], 1,690 sets of NIBP readings were obtained. A-third of readings were from infants and children >96 months, while 383 (22.6%) readings were from patients on inotropes. Multiparameter monitors gave significantly higher NIBP readings compared to MCS [median systolic blood pressure (SBP), 6.5 (6.4-6.7 mm Hg); diastolic blood pressure (DBP), 4.5 (4.3-4.6 mm Hg); mean arterial pressure (MAP), 5.3 (5.1-5.4 mm Hg); p < 0.05]. It was consistent across age, gender, and critical care characteristics. Multiparameter monitors overestimated SBP in 80% of readings beyond the maximal clinically acceptable difference (MCAD).

Conclusions

Non-invasive blood pressure readings from MCS and MPMs are not interchangeable; SBP was 6-7 mm Hg higher with the latter. Overestimation beyond MCAD was overwhelming. Caution is required while classifying systolic hypotension with MPMs. Confirmation with auscultatory methods is advisable. More studies are required to evaluate currently available MPMs in different pediatric age groups.

How to cite this article

Khan AA, Gupta PK, Baranwal AK, Jayashree M, Sahoo T. Comparison of Blood Pressure Measurements by Currently Available Multiparameter Monitors and Mercury Column Sphygmomanometer in Patients Admitted in Pediatric Intensive Care Unit. Indian J Crit Care Med 2023;27(3):212-221.

Evaluation of blood pressure trajectories and outcome in critically ill children with initial hypertension on admission to Paediatric Intensive Care

OBJECTIVE

Hypertension on paediatric intensive care (PICU) is associated with adverse outcomes. Management is complex; hypertension often represents a physiological adaptive response and exposure to hypertension could lead to altered pressure-flow autoregulation. International treatment consensus is to avoid rapid blood pressure (BP) reduction. Our aim was to examine if the rate and magnitude of BP reduction in hypertensive patients was correlated with harm.

PATIENTS AND METHODS

We performed a single centre, retrospective, observational study in a quaternary PICU analysing the first 24 h post admission high resolution BP profiles of children with admission BP above the 95^th centile. Individual BP profiles were analysed regarding both time spent and magnitude below a threshold; 75% of the admission BP in the first 24 h. Outcomes were organ support-free days at day 28, change in serum creatinine and PICU mortality.

MAIN FINDINGS

Of 3069 admissions in a 36-month period (2016-2018), 21.7% had initial hypertension on admission to PICU. A total of 3,259,111 BP measurements (99.4% invasive) were available. Pre-existing hypertension was documented in 4.9% of patients. Both time spent and magnitude below threshold BP was poorly correlated with duration of required organ support and risk of death after adjusting for PIM score, pre-existing hypertension and raised intracranial pressure. We did find an association with a rise in serum creatinine on both uni- and multivariable analysis.

CONCLUSIONS

The risk of harm due to early and significant reduction of raised blood pressure in critically ill children appears to be limited.