Abstract / Summary
Abstract Objective Arginine vasopressin (AVP) is a non-adrenergic vasopressor increasingly used in the management of shock. While it restores arterial pressure, its effects on the microcirculation remain uncertain, with potential for reduced regional perfusion and tissue oxygenation. The aim of this systematic review is to evaluate the effects of intravenous AVP and its analogues on microcirculatory perfusion across different haemodynamic conditions and vascular beds. Methods A systematic search of MEDLINE, EMBASE, and Web of Science was conducted. Animal and human publications evaluating the effects of intravenous AVP or analogues on microcirculatory perfusion assessed with in vivo microcirculatory imaging or flowmetry techniques were included. Publications were grouped by haemodynamic condition and vascular bed. Results Of 1693 records, 39 publications (31 animal, 7 human, 1 combined) were included, comprising 43 study-units and 152 individual measurements. Overall perfusion was decreased in 33%, unchanged in 48%, and increased in 19% of measurements, compared with baseline, saline, or other vasopressors. By haemodynamic condition, perfusion was decreased/unchanged/increased (n=study-units; % of measurements) in physiological conditions ( n = 14: 57/38/4), vasodilatory or septic shock ( n = 23: 24/55/21; versus baseline, fluid resuscitation or noradrenaline), haemorrhagic shock ( n = 3: 17/17/67; versus baseline, saline or noradrenaline), cardiac dysfunction or arrest ( n = 2: 0/67/33; versus adrenaline or noradrenaline) and cirrhosis-related portal hypertension ( n = 1: 0/0/100). Across vascular beds: gastrointestinal tract ( n = 18: 30/42/27), kidney ( n = 9: medulla 77/23/0, cortex 27/64/9), sublingual bed ( n = 7: 19/68/13), cerebral cortex ( n = 2: 0/67/33), cutaneous bed ( n = 6: 42/42/17), and conjunctiva ( n = 1, 100/0/0). Conclusion AVP and its analogues reduced microcirculatory perfusion most consistently under physiological conditions, whereas effects in vasodilatory or septic shock were more heterogeneous. Across vascular beds, the highest proportion of measurements showing reduced perfusion was in the renal medulla. These results highlight the divergent effects of vasopressin across vascular beds and clinical conditions.