Table 4.

Routes of crystalloid fluid administration

Route of Administration	Points to Consider
Oral	•Reserved for the euhydrated patient •Patients that are not vomiting •Offer ice cubes, small amounts of water, or an oral glucose and electrolyte solution •Give at frequent intervals to provide maintenance daily requirements
Subcutaneous	•Use only to treat mild dehydration in absence of other systemic signs •Balance isotonic polyionic sterile fluids (eg, Lactated Ringer solution) •Small dogs and cats without peripheral vasoconstriction •Do not exceed 10–20 mL/kg of fluid per injection site •Flow of fluids is based on patient’s comfort •Fluid absorbed within 6–8 h •Do not use hypertonic crystalloids, colloids, or dextrose-supplemented fluid for this route
Intravenous	•Moderately to severely dehydrated •Use when accurate deliveries of fluid volume and pharmacotherapeutic agents are required •Benefit: rapid and large administration of fluids, titration of fluids •Allows for potassium supplementation in IVF to replace that lost in vomitus
Intraperitoneal	•When intravenous catheter is not successful or possible because this provides rapid access to the circulation •Most commonly needed in emergency situations when immediate intravenous access is not possible for the pediatric or neonatal patient
Intraosseous	•Severely anemic pediatric patient •Consider for rewarming patients with hypothermia •Isotonic to mildly hypotonic fluid for rehydration •Intravenous route preferred when possible •Medulla does not collapse during hypovolemia