Page 655 - Fluid, Electrolyte, and Acid-Base Disorders in Small Animal Practice

642 SPECIAL THERAPY

Figure 26-18 Kangaroo Enteral Feeding Pumps for continuous or intermittent feeding.

In most instances, feedings can be increased to the total
calculated dose over 24 to 72 hours, unless anorexia
has been prolonged. Most anorexic patients begin volun-
tary food consumption after the second or third day.
If fluid losses are present, they can be replaced by admin-
istration of additional water along with the diet.
GASTRIC RESIDUAL VOLUMES (GRVS)
For human patients with feeding tubes that reside within
the stomach, gastric residual volumes (GRVs) are checked
every 4 to 6 hours, regardless of the method of feeding
(bolus or continuous). 65,73 The nasoenteric feeding tube
should be aspirated and the GRV should be recorded.
New evidence in veterinary medicine indicates that GRVs
can be slowly administered back through the nasogastric
tube over 5 minutes and flushed with 5 mL of water
before the next scheduled feeding with no overt gastroin-
testinal complications observed. 47 In many human
hospitals, intolerance to enteral feeding is assessed in part
by serially measuring gastric residual volumes
(GRVs). 71,72 High GRVs have been reported as a reason
Figure 26-19 Medfusion 2010i syringe pump for continuous or
intermittent enteral feeding of cats and small dogs. to stop feeding human patients. Gastric aspirates greater
than 150 to 250 mL in a 4-hour period were considered a
mark of intolerance in adults, and cessation of EN had
(Figure 26-19) to be suitable for either bolus or CRI been recommended to minimize risk of aspiration pneu-
feedings. This allows delivery of a precise volume over a monia. 65 In a study of low birth weight infants, delayed
given time frame, minimizing the possibility of gastric emptying was defined as GRVs greater than
“overdosing” a patient with an excess volume or giving 5 mL/kg in any 4-hour period. 48 However, routine sus-
boluses too rapidly. pension of EN due to large GRVs has been questioned in
If the animal has been anorexic for more than 72 human medicine, as there is no consistent relationship
hours, the volume administered over the first 12 to 24 demonstrated between aspiration and gastric residual
hours may be reduced by one third or one half of the total volumes. 53,69,73,74,93 The incidence of fourth hourly
RER to reduce the risk of gastrointestinal intolerance. GRV was not different between the continuous and