Table 2 Eligibility criteria

Inclusion criteria

(1) < 12 months of age (including premature newborns)

(2) Diagnosed with congenital heart disease*

(3) Admitted to the CICU

(4) Anticipated to require respiratory support^¶ for > 24 h during their CICU stay

(5) Have received ≤ 1 dose of stress ulcer prophylaxis^β during their current admission

Exclusion criteria

(1) Prior use of antacids^β in the past month for > 7 days

(2) Active gastrointestinal bleeding

(3) Active Helicobacter pylori infection

(4) Anticipated exposure to certain pharmaceuticals:

 (i) High-dose steroids (equivalent to 4 mg/kg/day of methylprednisolone)

 (ii) Intravenous non-steroidal anti-inflammatory drugs (i.e., ketorolac)

 (iii) Certain anticoagulants including high-dose aspirin, direct thrombin inhibitors, and GPIIbIIIa inhibitors

(5) Planned to undergo or recently has undergone gastrointestinal surgery within the last 4 weeks

(6) Supported by ECMO or VAD

(7) Currently enrolled in another conflicting interventional trial

(8) Known to be allergic to H2RAs

(9) Admitted for palliative care

(10) Prior enrollment in the study

(11) Primary provider declines enrollment