Which of the following is a good indicator that it is safe to extubate a patient?
Correct Answer: D
It is usually safe to extubate if the patient can swallow and/or the gag reflex has returned. One of the functions of an endotracheal tube is to prevent the aspiration of fluids into the lungs. Once a patient is able to swallow, the risk of aspiration has decreased dramatically. The patient's ability to blink, move its tail, or increase its respiratory rate would not indicate that the patient can protect its airway or that the tube could be safely removed.
Question 257
Which of the following amino acids is only essential to the feline diet?
Correct Answer: B
Cats, unlike other animals, do not have the ability to synthesize enough taurine to meet nutritional requirements, so it is essential that this amino acid is included in the diet or given as a dietary supplement. Cats cannot conjugate bile acids without proper taurine levels. Cats with a taurine deficiency can develop blindness and heart disease (dilated cardiomyopathy, a rare disease in cats) at an early age. Taurine is the amino acid that is essential to a feline diet, not alanine, glycine, or proline.
Question 258
In cattle, the preferred location for intramuscular injections is which of the following?
Correct Answer: B
Because cattle ultimately end up in the food chain, intramuscular injections are not recommended. However, now and again, we do need to administer medications in this fashion. If so, cervical muscles are the preferred site. We try to avoid using the gluteals, shoulder, semimembranosus, and semitendinosus muscles because any damage caused by the injection would lead to the carcass being condemned and economic loss to the farmer. Ideally, if any intramuscular injection is needed, ensure that you place it cranial to the shoulder in the neck where blemished tissue can easily be discarded without causing the whole carcass to be condemned at slaughter inspection. The landmark for cervical injections in cattle would be the triangle created by the shoulder, spinal column, and nuchal ligament in the lateral cervical muscles. Note that when giving intramuscular injections in cattle, it is commonplace to place the needle without the syringe and then attach it after the fact. However, if injections are needed, and concern for future use in the food chain is not present, pelvic limb muscles, including the gluteals and hamstring groups, can be used. In the thoracic limbs, the triceps brachii can be used. Finally, as above, the cervical muscles, such as the trapezius muscle, can receive intramuscular injections.
Question 259
When measuring central venous pressure, the tip of the central venous catheter must rest where?
Correct Answer: B
The tip of the catheter used in central venous pressure monitoring must rest in the cranial intrathoracic vena cava, or just outside the right atrium. Central venous pressure provides an estimate of right atrial pressure, helping to assess a patient's volume status and cardiac preload. The measure helps to monitor fluid therapy and provides an assessment of venous return and associated cardiac function. When monitoring central venous pressure, the tip of the catheter should not rest in the pulmonary artery, jugular vein, or cephalic vein.
Question 260
What is anisocoria?
Correct Answer: B
Anisocoria is the term used to describe a difference in the size of the patient's pupils. Anisocoria may be an indication that the patient has an ocular or neurologic disease. Anisocoria can occur with one normal and one mydriatic (dilated) pupil, one normal and one miotic (constricted) pupil, or one mydriatic and one miotic pupil. A malocclusion occurs when the jaw is not aligned properly. A flail chest occurs when a segment of the patient's rib cage moves in the opposite direction of the chest wall. Opisthotonos occurs when a patient's body is curled forward and stiffened.
