To evaluate the accuracy of blood pressure (BP) measured non-invasively (NIBP) compared with invasive arterial BP (IABP) measured by umbilical arterial catheter in neonates undergoing therapeutic hypothermia (TH) for hypoxic ischemic encephalopathy (HIE).STUDY DESIGN:
We conducted a retrospective study of neonates with gestational age (GA) ≥ 35 weeks with HIE who received TH. Paired NIBP and IABP measurements were obtained during TH and during normothermia.RESULT:
We collected 897 paired measurements from 40 infants, which included 623 pairs during TH and 274 pairs during normothermia. The mean ± s.d. differences in BP measured by NIBP compared with IABP in mmHg were - 0.2 ± 8.8 (P = 0.505) for systolic BP (SBP), - 4.5 ± 8.3 (P<0.001) for diastolic BP (DBP) and - 5.1 ± 7.5 (P<0.001) for mean BP (MBP) during TH; and - 1.3 ± 9.2 (P = 0.016) for SBP, - 7.5 ± 7.8 (P<0.001) for DBP and - 7.3 ± 6.8 (P<0.001) for MBP during normothermia. Overall 466/623 (74.8%), 324/623 (52.0%) and 363/623 (58.3%) of NIBP measurements of SBP, DBP and MBP, respectively, were clinically acceptable (defined as difference ≤ 15% of IABP reading) during TH; and 202/274 (73.7%), 118/274 (43.1%) and 148/274 (54.0%), were clinically acceptable during normothermia.CONCLUSION:
In term or near-term neonates with HIE, NIBP measurements are a robust method to determine SBP; however, DBP and MBP are underestimated. Determination of hypotension using the MBP measured non-invasively should be interpreted with caution.