Abstract 64: Association Between Blood Pressure Measurements, Vasopressor Use and Outcome in Post--Cardiac Arrest Patients Treated with Therapeutic Hypothermia from 4 Sites (COMICA Study Group)
Introduction: Specific hemodynamic optimization strategies have not been clearly described nor defined for post-cardiac arrest syndrome (PCAS) patients undergoing therapeutic hypothermia (TH).
Hypothesis: Patients who suffer worse neurologic outcomes will have more significant hemodynamic derangements in the early hours post-arrest than those with good neurologic outcome.
Methods: This is a collaborative study amongst 4 centers with aggressive TH protocols (BID, Penn, Pitt, VCU). It is a secondary analysis from prospectively collected data of out-of-hospital cardiac arrest patients who underwent TH. The primary outcome is neurologic status at hospital discharge measured as cerebral performance category (CPC), dichotomized into “good” (1 or 2) or “poor” (3, 4, or 5). Demographic information, initial rhythm and co-morbid conditions were obtained. Study variables were abstracted at baseline, 12, 24, 36 and 48 hrs. Variables recorded were systolic blood pressure (SBP) at baseline; MAP at each time point; worst, highest and lowest mean arterial pressure (MAP) for each 24 hr interval; vasopressor use.
Results: A total of 111 patients were enrolled. Patients were 61 ± 16.8 years, 59.5% male, with an initial rhythm of VF/VT in 50.5% of cases. The initial SBP for patients with good vs. poor outcome was 150 ± 37 mmHg vs. 128 ± 32 mmHg respectively (p=0.037). Patients in both groups had comparable MAPs at 12 hrs (91 vs. 87, p= 0.34) and at 36 hrs (86 vs. 81, p=0.113); however, the vasopressor use at these time points differed. At 12 hrs, vasopressors were used in 20% of patients with good outcome, versus 43.4% of patients with poor outcome (p=0.017). At 36 hrs, 31.4% of patients with a good outcome were on vasopressors vs. 50.7% with a poor outcome (p=0.06). In the first 24 hrs, subjects with good and poor outcome had equal distributions of their worst MAPs into the “low” (90 mmHg) categories. Conversely, in the second 24 hrs, patients with a poor outcome had a higher proportion of patients where their worst MAP was “low” versus those who had a good outcome (67% vs. 76%, ns).
Conclusions: Patients with poor neurologic outcomes have lower initial SBPs and a higher percentage of vasopressor use during TH versus patients with good neurologic outcomes.
- © 2012 by American Heart Association, Inc.