Catecholamines for shock: the quest for high-quality evidence

Abstract

Despite the established role of catecholamines for the treatment of circulatory shock in intensive care medicine, these drugs have been subjected to few randomised controlled trials with high methodological quality and patient-centred outcomes. The literature has been dominated by low-quality, case-control studies of the effects of synthetic catecholamines on surrogate haemodynamic end-points. A recent Cochrane systematic review of the effects of vasopressors on mortality from circulatory shock identified seven randomised controlled trials, none of which demonstrated any conclusive evidence of benefit of one inotrope/vasopressor over another. The review confirmed the persisting low methodological quality of these studies. Three higher-quality studies of catecholamines (noradrenaline, adrenaline, dopamine and vasopressin) have been completed, the results of which will provide some evidence of efficacy of catecholamines on mortality and resolution of shock. These studies may provide the basis for designing and conducting a large-scale, pragmatic, randomised controlled trial to analyse the effects of these commonly used drugs on patient-centred outcomes, such as mortality, resolution of organ failure and hospital length of stay. The results of such a study would be particularly important in geographical regions where access to inotropes/vasopressors other than adrenaline remains restricted.