The indications for gastric intubation include:
- emptying and gavage of the stomach in cases of suspected or known
- relief of gaseous distension in animals with gastric
- short-term administration of nutrients
- administration of diagnostic solutions such as barium
General gastric intubation is performed using a large bore
gastric tube. The diameter of the tube should be approximately the same size as an endotracheal
tube that would be used in the same animal.
|The length of the tube should be measured from the tip of
the nose to approximately the 9th intercostal space in order to assure that the
tip of the gastric tube is within the lumen of the stomach. Place a tape
marker (orange tape pointed to by blue arrow) to mark the proper
|| Over-insertion can result in
the tube hitting the gastric wall, flipping 180 degrees, and exiting back into the
esophagus. Large diameter tubes are by nature very stiff. Care should be used in their
placement, as gastric perforation can occur. The tube should be well lubricated.
Notice that the tube pictured has an end hole as well as side holes
(indicated by blue arrow).
Orogastric intubation is usually performed in the awake
animal with physical restraint when the purpose is to relieve gas distention or administer
barium. If the purpose is to gavage to remove toxic contents, heavy sedation or anesthesia
If awake, the animal is restrained in sternal recumbency
with the head in a neutral position.
||A speculum is placed to prevent the animal from chewing the
gastric tube. Commercial speculums are available. A 1 inch roll of tape makes an excellent
speculum and is minimally traumatic.
A large bore (12 ml) syringe casing cut off at the
end can also be used as a speculum, but the rough plastic is more traumatic to the oral
mucosa. The plastic speculum can be wrapped with adhesive tape to reduce trauma to the
oral membranes. The speculum is placed between the dental arcades and the muzzle is held
to prevent the animal from spitting out the speculum.
||The tube is introduced into the oral cavity with the head
in a normal position, not extended, not flexed.
|| You may be able to observe the tube
passing on the left side of the animals cervical region as it passes through the
cervical esophagus or you may palpate the gastric tube in the cervical region,
dorsal to the trachea.
||When the tube meets the cardia of the stomach there may be
some degree of resistance. This is especially true if the stomach is distended with solid
matter or air. A gentle rotation of the gastric tube may be necessary to pass through the
lower esophageal sphincter into the stomach.
Depending upon the gastric contents, when the tube enters the gastric lumen,
air may rush out, fluid may rush out, or you may have no identifiable sensation
that the tube is in the gastric lumen. The tube should be inserted to the
previously measured length (orange tape).
||Effective gastric lavage generally requires the animal be
sedated or anesthetized. The animal should have a cuffed endotracheal tube in place, and
the insufflation of the cuff should be checked immediately before passing the gastric
The animals head should be lowered.
Water, saline or a fluid solution
containing activated charcoal should be instilled in volumes of 5-10 ml/kg. After each
fluid installation, the fluid should either be drained out by gravity, or aspirated out by
using a syringe or suction pump. The gavage should be repeated 8-10 times.
The animal needs to be carefully monitored when recovering
from the anesthesia so that it does not vomit and aspirate residual gavage solution.