Your cardiac patient has an unstable angina history and is suspected of experiencing an ischemic event. He presents with chest pain, cool and clammy skin, and diaphoresis. If the event is being caused by unstable angina pectoris, which medication may be used to prevent an increase in the size of a thrombus if one is present?

Correct Answer: C

Rationale: The correct answer is C: Aspirin. Aspirin is used in the treatment of unstable angina to prevent platelet aggregation and reduce the risk of thrombus formation. It inhibits the enzyme cyclooxygenase, thus reducing the production of thromboxane A2, a potent platelet aggregator. Nitroglycerin (A) is used to relieve chest pain but does not prevent thrombus formation. Morphine (B) is used for pain relief but does not address thrombus prevention. Streptokinase (D) is a thrombolytic agent used to dissolve existing clots, not prevent their formation. In this case, aspirin is the most appropriate choice to prevent further thrombus formation in the setting of unstable angina.

Correct Answer: C

Rationale: The correct answer is C: Lidocaine. Lidocaine is used prior to intubation in head injury patients with increased intracranial pressure to minimize the potential increase in intracranial pressure caused by laryngoscopy and endotracheal tube insertion. Lidocaine acts as a local anesthetic and suppresses the cough reflex, reducing the risk of elevated intracranial pressure during intubation. Diazepam (A) and Lorazepam (B) are not typically used in this scenario and may cause respiratory depression. Procainamide (D) is an antiarrhythmic drug and is not indicated for reducing intracranial pressure during intubation.

Correct Answer: C

Rationale: The correct answer is C: Lactated Ringer's helps decrease acidosis in a hypovolemic patient. Lactated Ringer's contains lactate, which is converted to bicarbonate in the body, helping to buffer acidosis. Normal saline does not have this buffering capacity, making lactated Ringer's more beneficial in correcting acidosis in trauma patients. Choice A is incorrect because both normal saline and lactated Ringer's stay in the vascular system for a similar duration. Choice B is incorrect because neither normal saline nor lactated Ringer's can carry red blood cells. Choice D is incorrect because lactated Ringer's does not increase acidosis; it helps decrease acidosis.

Correct Answer: A

Rationale: The correct answer is A: Monro-Kellie Principle. This principle states that the total volume inside the skull remains constant, so an increase in one component (such as cerebral blood volume) must be compensated by a decrease in another (such as CSF volume) to maintain a normal ICP. This is crucial in head injuries to prevent dangerous elevations in pressure. B: Bernicke Principle does not pertain to intracranial pressure regulation. C: Fick Principle is related to cardiac output. D: Bernoulli's Principle is about fluid flow and pressure, not specific to ICP regulation.

Correct Answer: B

Rationale: The correct answer is B: To ensure any undeployed airbags do not discharge and cause an injury to the patient or anyone involved. It is important to disconnect the battery before attempting to enter the vehicle or extricate the driver because doing so can prevent any undeployed airbags from suddenly deploying during the extrication process. Deploying airbags can cause serious injuries to the patient or rescuers due to the force and speed at which they inflate. Disconnecting the battery helps to eliminate this risk and ensures a safer extrication process. Choice A is incorrect because the main concern is not about the vehicle moving during extrication. Choice C is incorrect as electrocution risk is more related to high-voltage components in hybrid or electric vehicles, not just the standard battery. Choice D is incorrect as the battery disconnection is primarily to prevent airbag deployment, not to prevent fires in the passenger compartment.