An appraisal of selection and use of catecholamines in septic shock - old becomes new again.

The use of catecholamines to defend and resuscitate patients with septic shock remains a cornerstone of intensive care medicine. The pharmacological support of the failing circulation during sepsis and septic shock should be directed at augmenting perfusion of vital organs and facilitating venous return, rather than peripheral arterial vasoconstriction. There appears to be a teleological rationale for primary use of catecholamines to augment failing endogenous neurohumoral and neuroendocrine cardiovascular systems. To this end, it seems intuitive to use the predominant naturally occurring catecholamine, noradrenaline, as the first-line agent for circulatory failure, although there are no definitive clinical trials to support this. Adrenaline has an established place in many parts of the world, particularly low-income countries, and appears to be equivalent to noradrenaline for reversing septic shock. There is increasing evidence for adverse neuroendocrine and immunological effects of dopamine, warranting circumspection about its use. The use of synthetic inotropes and vasopressors for septic shock remains limited, with little biological rationale. Clinicians should wait for definitive outcome-based trials of these expensive agents before incorporating them into practice. Supplemental endocrine replacement therapy with low-dose corticosteroids and vasopressin appears biologically plausible and has an emerging role. Results of large-scale, high-quality trials of endogenous catecholamines for sepsis and septic shock are awaited. These may provide additional, important information for evidence-based guidelines, which currently remain of limited clinical utility.