Page 485 - Clinical Small Animal Internal Medicine

46 Medical Management of Trauma and Burns 453

formula 30(BW in kg) +70 = kcal/day is both easy to use oxygen content has not passed. If a patient is exhibiting
VetBooks.ir and remember. When instituting a feeding plan, begin by clinical signs associated with anemia, is in hemorrhagic
shock refractory to crystalloid or colloid resuscitation, or
feeding a fraction (1/3 to 1/2) of the calculated resting
energy requirement (RER) for the first 24 hours with
cipated blood loss then transfusion of red blood cells
the goal of achieving full RER over the next 48–72 hours. is undergoing a planned surgical procedure with anti-
It is common for the actual delivered kcal to be less should be considered. The target packed red blood cell
than the calculated requirement due to the fact that ani- volume (PCV) for blood transfusion is also unknown but
mals may be intolerant of the volume or rate required to achieving a PCV of 25–30% is reasonable, with little evi-
meet the RER, the need to water food down (reducing dence that higher values are beneficial. Improving blood
the caloric density) to prevent tube clogging, or the oxygen content can subsequently improve wound healing
necessity to fast animals for sedation or anesthetic events. and prevent or ameliorate secondary injury associated
Selection of a calorically dense formula (≥1 kcal/mL) is with ischemia or inadequate oxygen delivery.
best in most settings to ensure that the caloric target is Since blood transfusion is becoming more common in
being reached. If available, the use of immune‐modulat- veterinary medicine, it is important to obtain a full
ing formulas enriched with omega‐3 fatty acids and anti- transfusion history from the owner prior to administra-
oxidants may be a good choice. tion of any blood product. Pretransfusion testing will
Parenteral nutrition (PN) has been associated with a vary by case according to how urgently the product is
variety of complications such as hyperglycemia, hyper- needed. If time allows then complete pretransfusion
lipidemia, electrolyte disturbance (hypophosphatemia, testing, including blood typing and major cross‐match,
hypokalemia), and septiciemia. Although enteral nutri- should be performed. Blood typing of cats is mandatory
tion is always preferable to parenteral nutrition, some- in all cases regardless of time sensitivity due to the
times it is not feasible due to intolerance of EN or potential for fatal reactions to first‐time transfusions.
nonfunctional GI tract (severe ileus, preexisting disease). Cross‐matching of cats should be considered in all
For patients that were healthy prior to trauma, PN is not transfusions if time permits due to the prevalence of
considered necessary for the first 5–7 days of hospi- preformed antibodies in this species. It is not necessary
talization while the patient’s progress is monitored. to cross‐match dogs receiving their first blood transfu-
If anorexia persists or GI dysfunction becomes evi- sion, as the existence of preformed antibodies is very
dent then PN should be instituted. uncommon, and in the emergency setting a universal
Trauma patients are at high risk for development of donor or DEA 1.1‐negative donor unit can be given with
ileus due to voluntary or involuntary immobilization, little to no pretransfusion testing. Animals that require
opioid administration, pain, and general anesthesia. multiple transfusions during a hospitalization should
Aggressive management of ileus should be attempted have a major cross‐match performed for all transfusions
with metoclopramide, cisapride, lidocaine, erythromycin occurring 72 hours after the first due to the risk of severe
or ranitidine. Consideration should be given prior to rou- hemolytic transfusion reaction.
tine treatment with H2 blockers due to the potential for The rate at which blood is administered is determined
bacterial overgrowth in the proximal GI tract and subse- by the patient’s volume status and cardiovascular stability.
quent complications. Ideally, the use of gastric alkaliniz- In patients that are in hypovolemic shock secondary to
ing medications would be based on evidence of gastric massive hemorrhage, blood can be administered as fast
ulceration or esophagitis or the probability of either of as it will flow into the patient. Under more controlled
these complications developing. circumstances, most blood transfusions are started at
reduced rates that are gradually increased with the goal
Transfusion of completing the transfusion over several hours. Close
Severely traumatized patients may require red blood cell attention should be paid to vital signs in an effort to
or plasma component therapy due to hemorrhage or detect transfusion reactions early.
development of complications such as DIC. Red blood Fluid overload is an uncommon complication in dogs
cell transfusion increases the oxygen‐carrying capacity receiving packed red blood cells but may be a concern in
of the blood and helps to reestablish the oxygen reserve cats (especially if underlying heart disease is present).
normally present in health. Determining a transfusion In addition to volume concerns, each red blood cell
trigger is clinician dependent and no clear guidelines transfusion will expose the patient to foreign antigen and
have been established. The decision is made on a case‐ will stimulate an immune response to a greater or lesser
by‐case basis, carefully weighing the pros and cons of degree. In patients that are already experiencing sys-
each transfusion. As a general rule, the more acute the temic inflammation, this second hit may precipitate fur-
drop in hemoglobin, the higher the transfusion trigger ther injury, as in the case of transfusion‐related acute
since the necessary time to adapt to the decrease in blood lung injury.