Impact of Midodrine Starting Dose on Time to Vasopressor Discontinuation in Shock Patients

Introduction: Patients admitted to intensive care units (ICU) often require vasopressors to maintain normotension and
can be difficult to wean, potentially leading to longer ICU stays. Midodrine has been used off-label for
vasopressor-sparing hypotension in the ICU but according to the MIDAS trial, did not accelerate
liberation from vasopressors when compared to placebo. However, midodrine is still used for
vasopressor weaning but there is no evidence describing an appropriate starting dose. Therefore, the
purpose of this study was to evaluate the safety, efficacy, and impact on the patient outcomes of the
midodrine starting dose in patients with various shock states on vasopressors.


Methods: This was a single-center, retrospective cohort study comparing patients receiving midodrine at low dose
( < 15 mg/day) or high dose (≥ 15 mg/day) and concomitant vasopressors. Patients in the ICU at Baptist
Health Medical Center from January 31, 2021 to June 1, 2024 receiving both therapies for at least 24
hours were evaluated. The primary outcome was time to vasopressor discontinuation between the two
groups. Secondary outcomes included ICU length of stay, hospital length of stay, in-hospital mortality,
number of midodrine dose escalations, time to midodrine discontinuation, rebound hypotension, and
percent change in total vasopressor requirements at 24 and 48 hours post-midodrine initiation.


Results: A total of 84 patients were included, 30 patients in the low dose group and 54 patients in the high dose
group. The primary end-point showed a median of 96 hours (IQR 48-144) to vasopressor discontinuation
in the high-dose group, as compared to 48 hours (IQR 24-162) in the low-dose group (p=0.458).Patients
in the high-dose group exhibited higher predicted ICU morality (SAPS II score of 52.6 vs. 41.5, P=0.011),
had a longer duration of vasopressors prior to midodrine initiation. There were no differences in
secondary outcomes.


Conclusions: Among patients receiving vasopressors and midodrine concomitantly, the high dose (≥ 15 mg) group did
not lead to a quicker time to vasopressor discontinuation when compared to the low dose ( < 15 mg)
group.