Cardiol Young. 2021 Jan;31(1):63-70.
doi: 10.1017/S1047951120003297. Epub 2020 Nov 3.
PMID: 33140712; DOI: 10.1017/S1047951120003297
Take Home Points:
- Prostaglandin E1 at an initial and maintenance dose of 0.01 μg/kg/minute was sufficient to maintain ductal patency in 83% in this study, instead of the standard starting dose of prostaglandin E1 is 0.05 μg/kg/minute. Starting low-dose prostaglandin E1 at 0.01 μg/kg/minute is a safe and effective therapy for critical CHD.
- Patients with pulmonary obstruction were more likely to require higher doses than patients with systemic obstruction. Postnatally diagnosed patients with systemic obstruction are also at a higher risk of dose escalation than prenatally diagnosed infants.
- The incidence of respiratory depression requiring mechanical ventilation was low and was mostly seen in premature infants.
Commentary from Dr. Manoj Gupta (New York, USA), section editor of Pediatric & Fetal Cardiology Journal Watch: Of the 153 eligible patients, 127 (83%) were started and maintained on a prostaglandin E1 dose of 0.01 μg/kg/minute until the end- point. Of the 26 patients who had their doses increased, the final dose was less than 0.05 μg/kg/minute in 15, 0.05 μg/kg/minute in five, and greater than 0.05 μg/kg/minute in two patients. 15 patients had their dose increased due to both echocardiographic findings and clinical factors suggesting ductal constriction. In systemic obstruction patients, these factors included blood pressure gradients, pulse abnormalities between upper and lower extremities, and elevated serum lactate levels. In pulmonary obstruction and inadequate mixing patients, the primary clinical factor driving dose increase was hypoxemia. In six patients, there was an echocardiographic finding of ductal constriction without corresponding clinical signs.
Of the 137 patients analyzed for respiratory depression, 38 (28%) had documented respiratory depression at a dose of 0.01μg/kg/ minute. In 10 of these patients, the respiratory depression was transient and did not merit initiation of respiratory support although four were started on caffeine. Fourteen patients (10%) were started on nasal cannula or high-flow nasal cannula, three patients (2%) were placed on continuous positive airway pressure, and 11 patients (8%) were mechanically ventilated via endotracheal intubation as a result of respiratory depression. Premature infants were more likely to experience respiratory depression (12/18, 67%) than term infants (26/117, 22%, p < 0.001). Mechanical ventilation was also more frequent in premature infants (6/18, 33%) than in term infants (5/117, 4%, p = 0.001).