Intra-arterial blood pressure (IABP) measurement, although considered the gold standard in critically ill children, is associated with certain risks and lacks widespread availability. This study was conducted to determine the differences and agreements between oscillometric non-invasive blood pressure (NIBP) and invasive IABP measurements in children. Inclusion criteria consisted of children (from 1 month to 18 years) admitted to the pediatric intensive care unit (PICU) of a teaching hospital who required arterial catheter insertion for blood pressure (BP) monitoring. The comparison between IABP and NIBP was studied using paired t -test, Bland-Altman analysis, and Pearson\'s correlation coefficient. In total, 4,447 pairs of simultaneously recorded hourly NIBP and IABP measurements were collected from 65 children. Mean differences between IABP and NIBP were -3.6 ± 12.85, -4.7 ± 9.3, and -3.12 ± 9.30 mm Hg for systolic, diastolic, and mean arterial BP, respectively ( p  < 0.001), with wide limits of agreement. NIBP significantly overestimated BP ( p  < 0.001) in all three BP states (hypotensive, normotensive, and hypertensive), except systolic blood pressure (SBP) during hypertension where IABP was significantly higher. The difference in SBP was most pronounced during hypotension. The difference in SBP was significant in children <10 years ( p  < 0.001), with the maximum difference being in infants. It was insignificant in adolescents ( p  = 0.28) and underweight children ( p  = 0.55). NIBP recorded significantly higher BP in all states of BP except SBP in the hypertensive state. SBP measured by NIBP tended to be the most reliable in adolescents and underweight children. NIBP was the most unreliable in infants, obese children, and during hypotension.

BACKGROUND: Accurate haemodynamic monitoring in the prehospital setting is essential. Non-invasive blood pressure measurement is susceptible to vibration and motion artefact, especially at extremes of hypotension and hypertension: invasive arterial blood pressure (IABP) monitoring is a potential solution. This study describes the largest series to date of cases of IABP monitoring being initiated prehospital.
METHODS: This retrospective observational study was conducted at East Anglian Air Ambulance (EAAA), a UK helicopter emergency medical service (HEMS). It included all patients attended by EAAA who underwent arterial catheterisation and initiation of IABP monitoring between 1st February 2015 and 20th April 2023. The following data were retrieved for all patients: sex; age; aetiology (medical cardiac arrest, other medical emergency, trauma); site of arterial cannulation; operator role (doctor/paramedic); time of insertion and, where applicable, times of pre-hospital emergency anaesthesia, and return of spontaneous circulation following cardiac arrest. Descriptive analyses were performed to characterise the sample.
RESULTS: 13,556 patients were attended: IABP monitoring was initiated in 1083 (8.0%) cases, with a median age 59 years, of which 70.8% were male. 546 cases were of medical cardiac arrest: in 22.4% of these IABP monitoring was initiated during cardiopulmonary resuscitation. 322 were trauma cases, and the remaining 215 were medical emergencies. The patients were critically unwell: 981 required intubation, of which 789 underwent prehospital emergency anaesthesia; 609 received vasoactive medication. In 424 cases IABP monitoring was instituted en route to hospital.
CONCLUSIONS: This study describes over 1000 cases of prehospital arterial catheterisation and IABP monitoring in a UK HEMS system and has demonstrated feasibility at scale. The high-fidelity of invasive arterial blood pressure monitoring with the additional benefit of arterial blood gas analysis presents an attractive translation of in-hospital critical care to the prehospital setting.

BACKGROUND: Both invasive and noninvasive blood pressure (invasive arterial blood pressure [IABP] and noninvasive BP [NIBP]) monitors are used perioperatively; however, they often produce different values. The reason for this discrepancy is not clear, and it is possible that the act of cuff inflation itself might affect the IABP values, especially with the recurrent cycling of NIBP cuff.
OBJECTIVE: The aim of this study was to determine the effect of ipsilateral NIBP cuff inflation on the contralateral IABP values.
METHODS: Prospective, observational study.
METHODS: One hundred consecutive patients were studied. The NIBP device was set to cycle every 5 min for a total of 6 times. During each cuff inflation cycle, changes in IABP values from the arterial line in the contralateral arm were recorded. A total of 582 measurements were included for data analysis.
METHODS: Chi-square, paired t-test, analysis of variance.
RESULTS: Mean (± standard deviation) changes in systolic BP (SBP), diastolic BP, and mean BP with cuff inflation were 6.7 ± 5.9, 2.6 ± 4.0, and 4.0 ± 3.9 mmHg, respectively. We observed an increase of 0-10 mmHg in SBP in majority (73.4%) of cuff inflations. The changes in IABP did not differ between the patients with or without hypertension or with the baseline SBP.
CONCLUSIONS: This study showed that there is a transient reactive rise in IABP values with NIBP cuff inflation. This is important information in the perioperative and intensive care settings, where both these measurement techniques are routinely used. The exact mechanism for this effect is not known but may be attributed to the pain and discomfort from cuff inflation.

The Philips Intellivue MP50 monitor provides a method for non-invasive, near-continuous blood pressure (BP) monitoring and is designed to be an alternative to direct intra-arterial BP (IABP) measurement. However, no studies have specifically compared non-invasive and invasive BP measurements using the monitor. The present retrospective study observed 515 patients undergoing surgery with general anesthesia, whose invasive (intra-radial, femoral or dorsalis pedis artery) and non-invasive (oscillometric) BP (NIBP) were monitored simultaneously using the monitor. These data were analyzed using correlations, regressions and Bland-Altman plots. The patients were placed in a supine position during surgery. The correlation data for invasive BP and NIBP measurements were: for intra-radial measurements, r2=0.51 (bias and precision, 11.04±15.22 and 14.76±11.64 mmHg, respectively) for systolic BP (SBP) and r2=0.27 (6.17±11.95 and 9.77±9.25 mmHg, respectively) for diastolic BP (DBP); for intra-femoral measurements: r2=0.57 (14.79±14.55 and 17.15±11.68 mmHg, respectively) for SBP and r2=0.45 (4.12±9.70 and 7.49±7.40 mmHg, respectively) for DBP; and for intra-dorsalis pedis measurements: r2=0.33 (13.00±16.81 and 17.34±12.28 mmHg, respectively) for SBP and r2=0.30 (0.17±11.27 and 8.44±7.46 mmHg, respectively) for DBP. According to this data, the NIBP measured by the Philips Intellivue MP50 monitor showed low positive correlations and poor agreement with the IABP, as calculated by Bland-Altman analysis. Therefore, the use of oscillometric BP measured by the monitor in surgery patients under general anesthesia is not generally recommended.

The gold standard for blood pressure measurement in pigs is direct monitoring of arterial pressure, but this is an invasive technique adding complexity to surgical procedures. We sought to compare direct measurements obtained via catheterization to more easily-obtained indirect measurements using a sphygmomanometer with an automated cuff. Simultaneous measurements via an arterial pressure transducer and a child-size cuff were performed in pigs undergoing abdominal surgical procedures under normotensive conditions. Correlation between direct and indirect measurements was good (r=0.881). Systolic blood pressures for the cuff were higher than those for arterial measurements, while diastolic pressures were lower for the cuff than arterial. A Bland-Altman analysis confirmed this bias at the extremes of the normotensive range. For highly accurate readings, especially under stressed conditions, direct arterial catheterization remains the preferred method of measuring blood pressure. When monitoring surgical procedures, the more convenient blood pressure cuff can provide reliable measurements.