TCRN II ANSWERS & RATIONALES (2020)

QUESTION ONE: The correct answer is D. The systemic inflammatory response syndrome is associated with vasodilation which in turn causes a decrease in the patient’s mean arterial pressure. A decrease in mean arterial pressure is a classic finding of SIRS. SIRS does not affect the patient’s level of pain. In fact, SIRS may cause a reduction in the level of consciousness causing the patient to be less aware of pain. Vasodilation decreases the glomerular filtration rate, causing a decrease rather than an increase in the urinary output. SIRS is unlikely to cause changes to the white blood cell count, but SIRS can be caused by an infection that would cause an increase rather than a decrease in the white blood cell count.

QUESTION TWO: The correct answer is B. Patients in both compensated and decompensated shock have beta-two adrenergic stimulation resulting in tachypnea. So, the patient’s respiratory rate will be increased in both compensated and decompensated shock (a respiratory rate of 12 breaths per minute is slower and not associated with shock). As the patient progresses from compensated to decompensated shock, the respirations become increasingly shallow due to increasing hypoxia of the respiratory muscles and the brain. The respirations do not remain deep.

QUESTION THREE: The correct answer is B. A 24-year-old woman may carry children in the future, therefore rH compatibility is important. Therefore, rH-positive blood (e.g. A-positive) should not be given. The B antigen in AB blood would also be incompatible, therefore this is contraindicated. Type 0 fresh frozen plasma contains A antibodies that may react to the patient’s own A-type blood cells, therefore Type 0 fresh frozen plasma is incompatible. Type AB fresh frozen plasma does not contain any antibodies and is considered the universal donor for fresh frozen plasma; therefore, this is compatible.

QUESTION FOUR: The correct answer is A. Permissive hypotension is most effective on adult patients with penetrating trauma to the torso who are likely to be transferred rapidly to the operating room. It is contraindicated in pediatric patients and patients with head injuries. A patient with a blood pressure of 60/40 mm Hg is unlikely to be adequately perfusing and requires some degree of resuscitation, therefore permissive hypotension is not appropriate.

QUESTION FIVE: The correct answer is C. Elevated leptin levels cause obese patients to have elevated blood viscosity. This in turn increases the risk for complications such as coagulopathies and VTE. The incidence of rib fractures is not necessarily higher in the bariatric patient. The additional adipose tissue may provide some protection of the ribs. Bariatric patients tend to have insulin resistance putting them at a higher risk of hyperglycemia as opposed to hypoglycemia. The incident of subdural hemorrhages is not higher in the obese patient.

QUESTION SIX: The correct answer is C. Burns to the lips, mouth and tongue, especially when accompanied by bruising to the area are strongly indicative of forcing a child to drink hot liquids. Children with abusive injuries tend to cry less than those with unintentional injuries. Crying disproportionately is not necessarily a sign of abuse. Intentional burns are more likely to be symmetrical as opposed to asymmetrical. When the stories of the child and the caregiver do not match or the story does not match the injury, the index of suspicion for intentional injuries increases. Although matching stories does not rule out abuse, it does indicate that there is a lower risk that the injury was caused by abuse.

QUESTION SEVEN: The correct answer is A. One of the goals in the treatment of post-traumatic stress disorder is to give the patient a sense of being in control. Many times, they have an intense response to triggers that cause the to relive the event and feel like they are being controlled by those triggers. Treatment may help them control those feelings. Although treatment may reduce anxiety and cause abnormalities in vital signs to be less dramatic, this is not necessarily a goal of treatment. Similarly, while treatment may allow a patient to return to the scene of trauma without experiencing stress, this is not a goal of treatment. Even with successful treatment, patients may feel stress if they return to the scene of the trauma. Medication is a part of treatment and a goal of treatment is not necessarily to allow the patient to function without medication but to use the medication to allow the patient to be able to carry out activities of daily living.

QUESTION EIGHT: The correct answer is B. An intracranial pressure of 10 mm Hg is within normal limits. A subarachnoid hemorrhage, an epidural hematoma and an intracerebral hematoma are all space occupying lesions and would cause an increase in intracranial pressure. A basilar skull fracture allows leaking of cerebrospinal fluid and is not associated with elevations in intracranial pressure.

QUESTION NINE: The correct answer is A. Patients who are obtunded, comatose or stuporous are unable to follow commands such as “lift your leg off the bed” because of their decreased level of consciousness. A lethargic patient is still able to follow simple commands such as this with appropriate stimulation.

QUESTION TEN: The correct answer is A. Mannitol is an osmotic diuretic that can cause profound dehydration that can result in renal failure. Serum osmolality levels above 320 mOsm are associated with renal failure in patient’s on mannitol. Mannitol has minimal impact on coagulation factors so monitoring prothrombin time will provide less helpful feedback on the effects of mannitol than serum osmolality. Similarly, mannitol has little effects on liver function and white blood cell counts, so monitoring these parameters is not as desirable as monitoring serum osmolality.

QUESTION ELEVEN: The correct answer is C. Proprioception is the ability to know how one body part is in relation to another. It may be negatively impacted with injuries to the anterior cord. To test for proprioception, the nurse asks the patient to close his or her eyes and then moves a part of the patient’s body (e.g. toe or finger) in a specific direction, asking the patient to identify which direction the body part is being moved. These is no need to obtain a full set of vital signs or elevate the head of the bed 30 degrees to test for proprioception. A tuning fork can be used to assess for damage to the anterior cord but is not useful for testing the presence of absence of proprioception.

QUESTION TWELVE: The correct answer is D. A retrobulbar hemorrhage (a hemorrhage behind the eye) can push the globe forward out of the socket, making it vulnerable to injury. A paper cup may be placed over the affected eye and affixed to prevent further injury to the eye until it can be treated by an ophthalmologist. An eye patch rather than a paper cup may be used in the treatment of a hyphema. Intubation with an endotracheal tube is more likely to be considered for a tracheal tear rather than a paper cup. A paper cup has no therapeutic value in treating an orbital fracture

QUESTION THIRTEEN: The correct answer is A. This rhythm strips indicates both ST segment elevation as well as a right bundle branch block, both of which are associated with a blunt cardiac injury. Blunt cardiac injuries frequently occur along with a fractured sternum. A cervical spinal cord injury is more likely to cause neurogenic shock which will cause bradycardia. This strip does not show bradycardia (furthermore, a right bundle branch block and ST segment elevation are not associated with cervical spinal cord injuries. A ruptured diaphragm may cause obstructive shock with a diminished QRS complex but it is not associated with ST segment elevation or a right bundle branch block. Common findings associated with a pericardial tamponade include tachycardia, small QRS complexes and a pulsus alternans, none of which are noted in this strip. ST segment elevation and a right bundle branch block are not associated with a pericardial tamponade.

QUESTION FOURTEEN: The correct answer is B. The lungs of the patient with ARDS become fibrotic and lose compliance. Higher tidal volumes may damage the lungs and even cause a pneumothorax. Therefore, a common strategy in managing ARDS is to decrease tidal volumes below what would be considered normal (4 – 8 mL/kg). This may result in elevated carbon dioxide levels. Fi02 would not be turned below normal and this has no therapeutic value in treating patients with ARDS. The respiratory rate may have to be increased to maintain minute volume if tidal volume is decreased. An effective strategy for managing ARDS is to increase rather than decrease PEEP.

QUESTION FIFTEEN: The correct answer is A. Rebound tenderness is associated with peritoneal irritation, including blood in the peritoneum. Bleeding would cause hypovolemic shock would cause a narrowing, rather than widening pulse pressure. Blood in the peritoneum would cause hyporesonance to percussion rather than hyporesonance to percussion. Abdominal distension requires several liters of blood to be visualized and is unlikely to be noted with a 500 mL blood loss.

QUESTION SIXTEEN: The correct answer is B. Manipulation of the pancreas during removal of the spleen puts the patient at risk of developing pancreatitis, which may be recognized by an elevating amylase level. Elevating platelet and white blood cell counts are normal findings in the first four days after trauma. An elevating base deficit indicates that the deficit is improving, that base levels are returning to normal, which is desirable.

QUESTION SEVENTEEN: The correct answer is B. Because pelvic binders must be applied tightly to reduce the incidence of bleeding in the pelvis, they can cause pressure ulcers. Because of this, definitive treatment should be undertaken in a timely manner to reduce the time a pelvic binder is left in place. Pelvic binders may reduce the incidence of a fat embolus by decreasing movement of fractured bone ends. A properly applied pelvic binder should not cause urinary retention or respiratory distress.

QUESTION EIGHTEEN: The correct answer is A. Patients with renal trauma may develop hypertensive episodes for as long as ten years after renal injury that may require treatment with hypertensives. Therefore, the patient should be taught to monitor for signs of hypertension. Patients with renal trauma have no higher risk of developing nuchal rigidity, petechial lesions or unilateral weakness, therefore this does not need to be included in the patient’s discharge plan.

QUESTION NINETEEN: The correct answer is C. Treatment for pelvic fractures in pregnant patients is not different than if the patient were not pregnant. The patient should receive fluid resuscitation based on hemodynamic parameters and a pelvic binder should be applied across the lower hips and symphysis pubis below the level of the uterus. Although the pelvic binder should be applied BELOW the level of the uterus to reduce injury to the fetus, if applied properly, it is not contraindicated and will not harm the fetus. The pelvic binder should be applied firmly to reduce blood loss.

QUESTION TWENTY: The correct answer is A. Cardiac compressions should be initiated as soon as a pregnant trauma patient becomes pulseless. Although compressions should be administered at the same rate as though the patient were not pregnant, hand placement should be higher (upper half of the sternum) then if the patient were not pregnant. Although an emergent cesarean section will be considered, this does not change the need for cardiac compressions and they should not be deferred.

QUESTION TWENTY-ONE: The correct answer is C. Superficial burns (e.g. sunburn) are reddened but do not blister. Compare this to a superficial partial thickness burn which blister (skin remains intact over burn but fluid leakage causes blisters). Deep partial thickness burns may or may not blister (depending on whether the skin is intact to collect fluid). They can appear mottled pink or white but will generally take on a white appearance by day two post-burn. Full thickness burns tend to appear dry and leathery.

QUESTION TWENTY-TWO: The correct answer is B. Fat embolism syndrome almost always results in occlusions within the pulmonary vasculature. This reduces movement of blood from the right ventricle through the pulmonary vasculature to the left ventricle. Decreased left ventricular filling reduces cardiac output thus reducing mean arterial pressure. Hypotension causes tachycardia rather than a reduced pulse rate. As blood backs up from the pulmonary circulation into the vena cava, central venous pressures elevate rather than decrease. Decreased blood flow through the lungs reduces the exchange of carbon dioxide in the lungs increasing rather than decreasing PaCO2 levels.

QUESTION TWENTY-THREE: The correct answer is B. A moist wound allows cells to migrate easily and enhance the resurfacing process, therefore the most effective dressing keeps wounds moist but does not dry them out. A dry wound inhibits epithelial cells from migrating and resurfacing a wound. If the wound is too wet, healing is hindered by macerating healthy tissue that surrounds the wound. If crusting is noted over a wound, new tissue cannot grow over the area.

QUESTION TWENTY-FOUR: The correct answer is B. A nightstick fracture is caused by a blow to the ulnar side of the arm resulting in an ulnar fracture without a fracture to the radius. The ulnar nerve runs along the ulna and can be impacted by this fracture. The ulnar nerve innervates the fourth and fifth finger. Disruption of the ulnar nerve may cause numbness to the tip of the fifth finger. Inability to fold the hand into a fist is associated with median nerve damage and this nerve is not susceptible to nightstick fracture. The radial nerve innervates the area between the thumb and the second finger. The radial nerve also allows an individual to extend the thumb into the “hitch hiker’s” sign. A nightstick fracture does not affect the radial nerve.

QUESTION TWENTY-FIVE: The correct answer is B. Ice should be applied to an orthopedic injury for 20 minutes out of every hour after an injury. This should continue for the first 48 hours, then heat should be applied to the area. Ice helps reduce swelling initially after the injury and heat helps to reabsorb it. Orthopedic injuries should be elevated ABOVE the level of the heart (unless there are indications of compartment syndrome) and elevation should continue if there is pain and swelling (not just for the first 48 hours).