Relearning what you thought you knew*

• Current recommendations for routine anesthetic fluid rates are for 10 mL/kg/hr to avoid adverse effects^6,7
• The use of a K-containing balanced electrolyte solution does not increase blood K in cats with urethral obstruction⁵¹
• LRS will not exacerbate lactic acidosis⁵²
• Patients with subclinical hypertrophic cardiomyopathy may be able to tolerate cautious fluid boluses for hypotension if their volume status is questionable, but they should be closely monitored for fluid overload and congestive heart failure⁵³
• LRS or acetated Ringer’s solution may be used in liver disease. LRS contains both D- and L-lactate and is unlikely to increase blood lactate levels⁵²
• When flushing an IV catheter, normal saline is as effective as heparin solution^48,54
• In general, the choice of fluid is less important than the fact that it is isotonic. Volume benefits the patient much more than exact fluid composition. Isotonic fluids won’t have a severe negative impact on most electrolyte imbalances, and their use will begin to bring the body’s fluid composition closer toward normal pending laboratory results that will inform the clinician of more specific fluid therapy³⁶

* See text for details.
LRS, lactated Ringer’s solution.