(940) Safety and Effectiveness of Droxidopa Administration for Persistent Hypotension via Gastric Tube

Introduction: Droxidopa is a norepinephrine prodrug approved for neurogenic orthostatic hypotension and is used off-label for persistent hypotension in patients who cannot wean off vasopressors. Package labeling states the capsules should be swallowed whole which limits use when a gastric tube (GT) is required for administration. Despite a lack of data, GT administration occurs in clinical practice. We report the safety and effectiveness of droxidopa administered via GT for persistent hypotension.

Methods: Adult patients admitted to intensive care units (ICU) at two academic medical centers from 7/2018 to 6/2023 who received droxidopa via GT for persistent hypotension were evaluated. Droxidopa use pre-admission or for an indication other than vasopressor weaning were excluded. The co-primary outcomes were time to vasopressor discontinuation (off vasopressors for ≥24 hours) and rates of abnormal vital signs (heart rate >100 BPM or MAP < 65 mmHg) after droxidopa initiation compared to the 24 hours prior to initiation. Secondary outcomes included mean norepinephrine equivalents pre- and post-initiation, adjunct oral agent use, and droxidopa dosing.

Results: 21 patients were included. Median age was 62 years, 33% were female, and most were admitted to a cardiac ICU (80.5%). The most common reason for admission was heart transplantation (19%). Median length of stay was 93 days (IQR 61-130) and 52.3% died in-hospital. In all cases, at least one adjunct agent was trialed prior to starting droxidopa, including midodrine (100%), pseudoephedrine (52%), fludrocortisone (48%), and pyridostigmine (9.5%). 954 droxidopa doses were administered via GT; nasogastric were the most common (57%). Median time to vasopressor discontinuation was 87 hours (IQR 34-175). Episodes of tachycardia (3.5% vs 1.1%, p=0.34) occurred at similar rates while hypotension (48% vs 37%, p=0.042) was less frequent post-initiation. Mean norepinephrine equivalent requirements were lower post-initiation than in the 24 hours pre-initiation (0.08 vs 0.05 mcg/kg/min, p=0.008). The most frequent starting dose was 100mg every 8 hours and the maximum dose was 600mg every 8 hours.

Conclusions: Droxidopa is a potential adjunctive agent for persistent hypotension. Droxidopa appears to be safe when administered via GT despite labeling to avoid opening capsules.