Start treating this cat’s shock with 5 ml/kg of LRS over 20 minutes. Check cardiovascular parameters before, and just as the bolus finishes, for evidence of volume responsiveness, hallmarked by increases in heart rate and improvements in pulse quality, blood pressure, and mucous membrane color.
Starting with smaller boluses works with, rather than against, the physiology of feline shock. Cats develop early decompensatory shock; they become bradycardic, hypothermic, and hypotensive within minutes of developing shock. These changes enhance capillary leak, making it harder for the fluids to remain within the vasculature.
The lungs are the cat’s shock organ, so at high risk of developing pulmonary edema and lung injury. This patient already has evidence of lung injury (tachypnea, pulmonary crackles), so he is especially at risk. Additionally, small boluses reduce the possibility of dislodging clots, an important consideration in any trauma.
Small, repetitive boluses allow the clinician to titrate the dose of fluids to treat the pet but avoid complications. Do not give the entire crystalloid shock dose for a cat (60 ml/kg) all at once.
Additional measures to help this cat: provide oxygen, analgesia (a pure mu opioid like hydromorphone), and gentle external warming to improve comfort and hemodynamics.
