FREE CFRN MCQ Questions and Answers
Which of the following readings from an adult's arterial blood gas is consistent with metabolic acidosis?
Bicarbonate (HCO3-) less than 22 mEq/L and a pH less than 7.35 are consistent with metabolic acidosis, which may result from severe diarrhea, starvation, diabetic ketoacidosis, kidney failure, and aspirin toxicity. Symptoms may include headache, altered consciousness, and agitation from lethargy to coma. Cardiac dysrhythmias and Kussmaul respirations are common. The other readings listed in the question indicate the following:
‥ HCO3 of more than 26 mEq/L and a pH of more than 7.45 are consistent with metabolic alkalosis
‥ PaCO2 of 35–45 mmHg and PaO of 80 mmHg or more are normal adult readings
‥ PaCO2 more than 55 mmHg and PaO2 less than 60 mmHg are consistent with acute respiratory failure in a previously healthy adult.
Which of the following situations completely rules out nasotracheal intubation?
A patient injured in a vehicle accident is being evacuated through hilly terrain at a height of more than 5000 feet. Due to a broken pump, the patient gets intravenous (IV) fluids by gravity. What impact will the IV infusion have when the altitude is raised to more than 5000 feet?
With this rise in altitude, the intravenous (IV) flow will increase, necessitating modifications to the flow rate. When feasible, a pump that adjusts to maintain a specific flow rate should be employed since barometric pressure impacts the flow rate. The barometric pressure drops as the altitude rises, and the increased flow in the IV tubing is made possible by the lower pressure. This may impact the dosage of IV drugs given. Cabins for fixed-wing aircraft traveling at high altitudes are pressurized, but only to a height of 6000–8000 feet, not sea level.
To commit suicide, a 17-year-old girl ingested an excessive amount of acetaminophen (thirty 500-mg pills). She informed her parents, who made an emergency call eight hours later. Which of the subsequent initial emergency treatments is appropriate?
N-acetylcysteine best protects the liver if administered within 8 hours of acetaminophen intoxication. Since 8 hours have passed in the scenario outlined in the question, the antidote must be administered immediately because it reduces hepatotoxicity even after 24 hours. Although activated charcoal may have some protective benefits if administered within 4 hours of intake, gastrointestinal decontamination is most successful when done within 1 hour of administration. The Rumack-Matthew nomogram illustrates toxicity, with serum levels greater than 150 mg necessitating an antidote. The initial dosage of the 72-hour N-acetylcysteine regimen is 140 mg/kg (PO), followed by 17 further doses of 70 mg/kg every 4 hours (orally or intravenously).
A tornado has injured several people and left a small village with major damage. The nearest medical facility is 150 miles distant. Although there is only one aircraft available for transfer, ambulances are expected to show there in 15 minutes. Which of the following patients needs to be flown after triage?
The newborn or infants may still be viable if the mother is in active preterm labor with a singleton or multiple deliveries at 22 weeks or more gestation. Burns that entail an explosion with respiratory difficulty or disorientation, unconsciousness, or burns that cover 18% or more of the body surface area (second or third-degree burns), must be transported by air. A fracture may be rendered immobile for land transportation. Injury to a limb is less urgent unless combined with extensive bleeding or compromised circulation. Penetrating injuries (such as shrapnel, gunshot wounds, or stabbing) to the head or trunk frequently necessitates air transfer, especially with prolonged unconsciousness.
This person assesses Pulsus paradoxus:
Systolic blood pressure measurements are used to examine pulsus paradoxus. When breathing normally, the blood pressure slightly drops during intake while the heart rate rises and rises slightly during expiration as the heart rate falls. The pulsus paradoxus, assessed by identifying the initial systolic reading during exhale and reducing blood pressure cuff measurements until the systolic pressure can be heard during both cycles, exaggerates this. Positive for pulsus paradoxus is a more than 10 mmHg difference between the systolic reading taken during expiration alone and the reading taken between inhalation and exhalation.
As he waits to be airlifted from a tiny rural hospital to a university hospital 200 miles from the scene of the accident for possible limb reattachment, a homeless guy who had recently suffered a horrific below-knee amputation turns violent and disoriented. Which of the following is the most appropriate initial action?
In order to protect personal safety as well as the safety of the medical and flight crew, patients who are aggressive or confrontational need be physically confined for transport and may also need chemical restraints. It is not a good idea to leave the patient in the hospital because the majority of rural hospitals lack the expertise and equipment necessary to perform limb reattachments. The likelihood of a successful reattachment may be lowered if ground transportation is delayed by waiting or making other arrangements.