PURPOSE: There is a growing body of literature on vasopressor use and outcomes in septic shock. Evidence suggests that resistance to dopamine as a first-line vasopressor is an independent predictor of mortality in patients with vasopressor-dependent septic shock. It is uncertain whether this is related to increased severity of illness and if this is unique to dopamine as a first-line vasopressor. We present a prospective analysis of a database of patients with vasopressor-dependent septic shock to evaluate outcomes related to vasopressor resistance (VR).
METHODS: We evaluated a database of 108 patients with vasopressor-dependent septic shock who had been randomized to protocol-directed management with dopamine (DA) or norepinephrine (NE) as the first-line vasopressor after fluid resuscitation. VR was defined as the need for more than one vasopressor to maintain a mean arterial pressure ≥60mmHg or systolic blood pressure ≥90mmHg. We evaluated the incidence of VR in patients with septic shock, whether VR is associated with 28-day mortality, and whether DA and NE have an equal incidence of VR. Data were analyzed with Chi-squared analysis. A p≤0.05 was considered significant.
RESULTS: One hundred and eight patients with well defined septic shock were included in the analysis. Fifty (46.3%) had VR. VR patients had a significantly higher 28-day mortality (32/50, 64% vs. 17/58, 29%; p<0.001). Severity of illness, measured by APACHE II scores, was also significantly higher in the VR group (p=0.002). There was no difference in the incidence of VR between the DA and NE groups (28/58, 48% vs. 22/50, 44%; p=0.66). Of the patients who had VR, the first-line vasopressor was not associated with a difference in mortality (p=0.22).
CONCLUSION: VR is common in patients with septic shock and there is an increased 28-day mortality in this group of patients. There is no difference in the incidence of VR in septic shock patients managed with dopamine vs. norepinephrine as the first-line vasopressor.
CLINICAL IMPLICATIONS: Vasopressor resistance may be marker of severity of illness rather than an independent risk factor for mortality.
DISCLOSURE: Serene Shashaa, None.