ELBW in first 72 hours Cardiovascular monitoring
Treatment of “isolated hypotension” is controversial (studies described increase IVH and no change in mortality).
GA in weeks as minimum mean blood pressure lacks strong data (but is the most conservative vs other normative tables)
mBP < GA should prompt complimentary evaluations: history suggestive of volume loss assess perfusion (refill, physical exam, baseline neurological status), acid-base status, trend and clinical setting.
Clinical diagnosis of shock difficult to establish
Based on exam with or without hypotension: prolonged CRT, cold extremities, ↓ urinary output, metabolic acidosis. Should assess perfusion.
References for normal blood pressure in premature newborns:
Giesinger RE, McNamara PJ: Hemodynamic instability in the critically ill neonate: An approach to cardiovascular support based on disease pathophysiology. Semin Perinatol 2016;40:174-188.
Mean blood pressure by age and GA (10th percentile) [1,2]: Based on the study by Nuntnarumit et al. [2]: “Gestational age and postnatal age dependant nomogram for mean blood pressure values in neonates during first 3 days. (…) Each line represents the lower limit of 80% confidence interval of mean blood pressure for each gestational age group. Thus, 90% of infants for each gestational age group are expected to have a mean blood pressure equal to or greater than the value indicated by the corresponding line.” [1]
(1) H William Taeusch M, Ballard RA, Gleason CA, Avery ME: Avery's Diseases of the Newborn. Elsevier Health Sciences, 2005.
(2) Nuntnarumit P, Yang W, Bada-Ellzey HS: Blood pressure measurements in the newborn. Clinics in perinatology 1999;26:981-996, x.
Corresponding blood pressure (90th and 10th percentile) by weight: De Luca D, Romain O, Yousef N, Andriamanamirija D, Shankar-Aguilera S, Walls E, Sgaggero B, Aube N, Tissières P: Monitorages physiopathologiques en réanimation néonatale. Journal de Pédiatrie et de Puériculture 2015;28:276-300.
Treatment of hypotension and hypoperfusion
Hypotension with hypoperfusion treated based on assumed etiology
If evidence of volume loss: Placenta praevia, abruption, blood loss from umbilical cord, fetal anemia, or fetal-maternal transfusion: administration of volume expander such as NS, or O Rh-negative blood may be used as an initial dose of 10 mL/kg. Slow infusion (over 30 minutes) or faster if clinically indicated. May be repeated. Albumin is not generally recommended.
In absence of suspicion of hypovolemia: Use volume expansion judiciously (some data = increased mortality)
First line of inotrope: dopamine or epinephrine when assumed vasomotor dysregulation, dobutamine when assumed to be myocardial dysfunction (start at 5 and up to 15 mcg/kg/min).
Hydrocortisone (30 mg/m2/day IV divided q 8h or 1 mg/kg/dose IV q 8hours) considered if: Suboptimal response to inotropes, suspected adrenal suppression, presence of severe PPHN (Vargo et al. 2011, Perez et al. 2014)
Consider obtaining ECHO in 24 hours after start of inotropes to guide management – consider as early as possible. Wean inotropes aggressively as soon as hemodynamic status stabilized then hydrocortisone may be weaned or stopped in case of short duration of use. Data regarding inhaled nitric oxide (iNO) in preterm infants is lacking.