Effectiveness of intravenous fluid resuscitation in hypotensive cats: 82 cases (2012-2019).

Abstract

To evaluate the effectiveness of intravenous fluid resuscitation in hypotensive cats in an emergency room setting. Secondary objectives were to investigate changes in heart rate (HR) and body temperature (BT) in response to fluid resuscitation, and the association of these changes with patient survival. Retrospective study. University teaching hospital. Eighty-two cats with confirmed hypotension. None. Medical records from 2012 to 2019 were searched for cats that had documented systemic arterial hypotension (blood pressure measured using a Doppler ultrasonic flow probe [DBP]<90mm Hg) on presentation to the emergency room. Data collected included patient characteristics and DBP, HR, and BT before and after fluid resuscitation, type and volume of fluids administered, and outcome. The median DBP before and after resuscitative fluid therapy in all cats was 65mm Hg (range, 20-85mm Hg) and 80mm Hg (range, 20-128mm Hg), respectively (P<0.001). However, only 30 cats (37%) were classified as responders to fluid resuscitation (DBP≥90mm Hg following bolus therapy). The mean HR and median BT before resuscitative fluid therapy was 159/min and 36.7°C. Following fluid resuscitation, where measured, the mean HR and median BT was 154/min (P=1.00) and 35.9°C (P=1.00). No significant differences in HR and BT were identified between responders and non-responders. Cats had a low survival rate of 7%. All survivors (n=5) were initially bradycardic (HR<160/min), compared to only 45% of non-survivors (P=0.4). Bolus fluid resuscitation effectively increases blood pressure in hypotensive cats; however, it does not result in normalization of blood pressure, HR, or BT in the majority of cases.