Hydrocortisone therapy in a cat with vasopressor-refractory septic shock and suspected critical illness-related corticosteroid insufficiency

Pisano, Simone R. R.; Howard, Judith; Posthaus, Horst; Kovacevic, Alan; Yozova, Ivayla D.

Reports of CIRCI in veterinary literature are limited to rare case reports and evaluation of the HPA axis in small groups of critically ill animals. In most veterinary publications, evaluation of HPA-axis impairment was based on delta cortisol values (the difference in cortisol concentrations before and after administration of adrenocorticotropic hormone [ACTH]) [10] . Lower delta cortisol values and higher free cortisol fractions were reported in six dogs with septic shock compared to healthy controls [11] . In one study, dogs with severe trauma, sepsis or gastric dilation-volvulus were found to have decreased delta cortisol values compared to controls. Furthermore, dogs with lower delta cortisol values were more likely to receive vasopressors [12] . In another report, both hypotension and decreased survivals were found to be associated with lower delta cortisol values in septic dogs [13] . Decreased delta cortisol levels were additionally reported in a small population of critically ill cats [14] . Despite such reports in the veterinary literature, current recommendations in human medicine do not support use of the ACTH-stimulation test to identify patients with CIRCI requiring corticosteroid treatment [4, 9, 15] . Instead, CIRCI is suspected when fluid therapy and vasopressor-resistant shock (usually failure to maintain SAP > 90 mmHg or MAP > 65 mmHg) are responsive to hydrocortisone administration [4, 15, 16] . Likewise, the diagnosis of suspected CIRCI in the cat in the present report was based on clinical findings and response to therapy.