Phenylephrine use ups death risk in septic shock patients

Septic shock patients, particularly those with ongoing tachycardia, are at greater risk of mortality when treated with phenylephrine, according to a study.

“Phenylephrine is a selective α₁-receptor agonist used to manage shock,” the authors said.

This retrospective chart review, conducted from September 2015 to September 2017, evaluated mortality in adult patients admitted to an intensive care unit (ICU) on vasopressors and treated with phenylephrine for the management of septic shock.

The authors divided patients into two groups: those treated with phenylephrine and those treated without phenylephrine. Mortality was the primary outcome, while secondary ones included days on vasopressors and ICU length of stay.

Subgroup analyses were also carried out: one for phenylephrine as first-line therapy and another for patients with tachycardia at initiation of vasopressors. The authors excluded patients on phenylephrine for salvage therapy.

A total of 499 patients were recruited for this study, of whom 148 (32 percent) were enrolled in the phenylephrine group.

Phenylephrine use contributed to a higher rate of mortality (56 percent vs 41 percent; p=0.003). However, no difference was observed in the days on vasopressors or ICU length of stay.

Notably, patients who had ongoing tachycardia and treated with phenylephrine were also more likely to die than those without tachycardia (54 percent vs 36 percent; p=0.02). When phenylephrine was started as the initial vasopressor, no difference was noted in mortality among patients.

“Current guidelines for septic shock recommend limited utilization of phenylephrine due to the lack of evidence available,” the authors said. “This deviates from previous guidelines, which had recommendations of when utilization may be appropriate.”