Effects of continuous haemofiltration on serum enzyme concentrations, endotoxemia, homeostasis and survival in dogs with severe heat stroke

Abstract Aim To examine the effectiveness of continuous haemofiltration as a treatment for severe heat stroke in dogs. Methods Dogs were randomly allocated to a control or continuous haemofiltration group (both n = 8). Heat stroke was induced by placing anaesthetised dogs in a high temperature cabin simulator. Upon confirmation of heat stroke (rectal temperature > 42 °C, mean arterial pressure (MAP) decrease > 25 mmHg), dogs were removed from the chamber and continuous haemofiltration was initiated and continued for 3 h for dogs in the continuous haemofiltration group. Dogs in the control group were observed at room temperature. Results Rectal temperature, haemodynamics, pH, blood gases and electrolyte concentrations rapidly returned to baseline in the continuous haemofiltration group, but not the control group. After 3 h, rectal temperature was 36.68 ± 0.51 °C in the continuous haemofiltration group and 39.83 ± 1.10 °C in the control group ( P < 0.05). Continuous haemofiltration prevented endotoxin and all serum enzyme concentrations from increasing and caused malondialdehyde concentrations to decrease. After 3 h, endotoxin concentrations were 0.14 ± 0.02 EU ml−1 in the continuous haemofiltration group and 0.23 ± 0.05 EU ml−1 in the control group ( P = 0.003), while malondialdehyde concentrations were 4.86 ± 0.61 mmol l−1 in the continuous haemofiltration group and 8.63 ± 0.66 mmol l−1 in the control group ( P < 0.001). Five dogs died in the control group within 3 h, whereas no dogs died in the continuous haemofiltration group. Conclusions Continuous haemofiltration rapidly reduced body temperature, normalised haemodynamics and electrolytes, improved serum enzyme concentrations and increased survival in dogs with heat stroke. Continuous haemofiltration may be an effective treatment for heat stroke.