Diastolic Blood Pressure During CPR and Return of Spontaneous Circulation in Children

An estimated 15,000 pediatric in-hospital cardiac arrests (IHCAs) occur annually in the United States, with a mortality rate that remains high and appears to have plateaued since 2010.¹ One factor that is associated with return of spontaneous circulation (ROSC) in IHCA is the maintenance of diastolic blood pressure (DBP) greater than or equal to 25 mm Hg in infants younger than 1 year old and 30 mm Hg in children between 1 and 19 years of age. These parameters are included in resuscitation guidelines that use DBP values as physiologic markers of CPR quality. However, data that support these parameters are primarily based on studies that measured DBP during the first 10 minutes of CPR.² The trajectory of DBP in pediatric IHCA after 10 minutes and its association with outcomes are unknown. 

Loaec et al³ sought to do the following: (1) describe the course of DBP throughout the entire duration of pediatric IHCA and compare trends between those who obtain ROSC and those who did not, and (2) examine the association between achieving optimal DBP and ROSC after prolonged (>10 minutes) CPR. They hypothesized that DBP thresholds can be maintained during prolonged CPR and that maintenance of these thresholds would be associated with ROSC achievement.

In this single-center, retrospective study, the primary outcome was sustained ROSC regardless of CPR duration.³ Secondary outcomes included return of circulation via extracorporeal CPR (ECPR); survival to hospital discharge; and survival with a favorable neurologic outcome, defined as a Pediatric Cerebral Performance Category score of 1, 2, or no worse than baseline. Subjects were chosen from the Children’s Hospital of Philadelphia Resuscitation Database, which was used to identify IHCA lasting one minute or more in patients aged 18 years or younger who were admitted to an ICU between 2017 and 2023. Demographics and clinical data, including monitor waveform data, were obtained. To evaluate DBP, patients were required to have four 15-second epochs of evaluable DBP data after the first 10 minutes of CPR. DBP was defined as the average of data points within 60% to 70% of the peak-to-peak cycle. Categorical data were compared using the Fisher exact test, and continuous variables were compared using the Wilcoxon rank-sum test. Linear regression models were used to assess trends in DBP. Univariate regression models were used to evaluate ROSC across different DBP thresholds.

Of the 325 IHCA events in the database, 118 met inclusion criteria, and 46 patients did not have ROSC within the first 10 minutes of CPR and did have evaluable DBP data after 10 minutes. In both cohorts, there were increases in DBP during the first five minutes of CPR, which decreased between minutes 5 and 10 and then stabilized after 10 minutes. In patients with prolonged IHCA, 37 (80%) had event-level average DBP above the recommended thresholds after 10 minutes of CPR, and 35 (76%) had average DBP values above the thresholds. Subjects who achieved ROSC within the first 10 minutes had a higher average DBP than those who required prolonged CPR (44 mm Hg vs 36 mm Hg, respectively). In the prolonged CPR cohort, the average DBP during the first 20 minutes of CPR was not different between patients who had ROSC and those who did not (33.8 mm Hg vs 34.8 mm Hg, respectively). It was noted, however, that the DBP increased during the first 20 minutes in patients with ROSC, whereas it fell in those who did not have ROSC. A similar finding was noted in subjects who needed less than 10 minutes of CPR as their DBP increased during the first 10 minutes compared with the prolonged CPR group. In the prolonged CPR group, 11 of the 37 (29.7%) patients who met DBP thresholds had ROSC, while only one of the other nine (11%) patients who did not meet the thresholds had ROSC. In the logistic regression models, neither event-level nor average DBP was significantly associated with ROSC after the first 10 minutes of CPR. However, patients who met higher thresholds (>30 mm Hg in infants and >35 mm Hg in children) after the first 10 minutes had higher odds of ROSC. In subjects who needed prolonged CPR, survival to hospital discharge and change in functional status were not different in subjects who achieved DBP greater than threshold values compared to those who did not.

In this study, the authors characterized the trajectory of DBP during an entire CPR cycle.³ While patients with higher average DBP and a steeper rise in DBP within the first 10 minutes were associated with ROSC, patients with prolonged CPR did not demonstrate any association between DBP (at current thresholds) and ROSC. Only higher thresholds and increasing DBP were associated with ROSC, which should be considered in patients who require CPR for greater than 10 minutes. The authors identify limitations in this study, including the use of a single center and the high proportion of patients with congenital heart disease, which may differ from other centers and limit generalizability. Additionally, ECPR was used in some of the patients who did not achieve DBP threshold, thereby creating a selection bias.

Maintaining DBP above thresholds set by guidelines for pediatric IHCA is necessary but may not be sufficient in patients who need CPR for greater than 10 minutes. Additionally, in those with prolonged CPR, setting higher goals for DBP may also be necessary to achieve ROSC. Further studies should perhaps focus on patient and time-specific goals when examining prolonged IHCA. 


References

1. Holmberg MJ, Wiberg S, Ross CE, et al. Trends in survival after pediatric in-hospital cardiac arrest in the United States. Circulation. 2019;140(17):1398-1408.
2. Berg RA, Morgan RW, Reeder RW, et al. Diastolic blood pressure threshold during pediatric cardiopulmonary resuscitation and survival outcomes: a multicenter validation study. Crit Care Med. 2023;51(1):91-102.
3. Loaec M, Patterson E, Reeder R, et al. Diastolic blood pressure during pediatric in-hospital cardiac arrest: trends and associations with outcomes. Crit Care Med. 2026;54(6):1399-1409.