BCEN CFRN Practice Test

Platelets, also known as thrombocytes, play a crucial role in hemostasis, the process that prevents and stops bleeding. They achieve this by aggregating to form clots and releasing chemicals that aid in blood coagulation. Even though other answers mention the general role of blood elements like transporting oxygen or fighting infections, these are functions of red blood cells and white blood cells, respectively.

The presentation of irritability, vomiting, and a bulging fontanelle in an infant strongly suggests increased intracranial pressure (ICP). This is a critical condition often caused by head trauma, which requires immediate medical attention. Although dehydration can present with vomiting, it would not typically cause a bulging fontanelle. Meningitis could present with similar signs but less likely following a fall. Gastroenteritis usually presents with vomiting and diarrhea but does not cause a bulging fontanelle.

The effectiveness of NIV in patients with respiratory distress is primarily indicated by improvement in clinical signs such as alleviation of labored breathing, increased oxygen saturation levels, and improvement in arterial blood gases. Specifically, an increasing SpO2 to above 90% after starting NIV suggests that the intervention is providing adequate respiratory support. On the other hand, absent breath sounds or accessory muscle usage might indicate progressing severity, and bradycardia may suggest hypoxia or other complications.

Administering high-flow oxygen via a non-rebreather mask ensures that the patient receives a high concentration of oxygen to alleviate hypoxia, which is crucial given the patient's immediate symptoms. Bag-valve-mask ventilation is typically reserved for patients who are unresponsive or unable to maintain their airway, while CPAP and BiPAP are more suited for patients with stable respiratory rates who need assistance with ventilation.

The patient is likely experiencing obstructive shock due to cardiac tamponade, which is indicated by his hypotension, jugular venous distension, and muffled heart sounds. Pericardiocentesis is the most appropriate intervention to relieve the pressure around the heart and restore cardiovascular stability. Administering intravenous fluids and blood products can support blood pressure but will not directly address the cause. Vasopressors may temporarily increase blood pressure but still do not remove the underlying obstruction.

The administration of an inotropic agent like dobutamine is the most effective intervention in this scenario. Dobutamine increases cardiac output by enhancing myocardial contractility and improving stroke volume. This optimizes cardiac perfusion and helps to decrease myocardial workload, which is crucial in managing cardiogenic shock. While defibrillation is essential in life-threatening arrhythmias and fluid administration is critical in hypovolemic shock, they are not as directly effective in improving myocardial perfusion and reducing cardiac workload in cardiogenic shock due to AMI. Administering nitroglycerin primarily affects preload and coronary vasodilation but does not address myocardial contractility as effectively as dobutamine.

Implementing regular debriefings helps manage stress by providing a structured opportunity for flight transport nurses to process the events of the mission, share experiences, and receive emotional support from peers and supervisors. This strategy promotes mental well-being and team cohesion.

The most appropriate initial intervention when a patient on a balloon pump develops a new dysrhythmia is to assess and adjust the timing of the pump. The device's effectiveness heavily relies on proper timing relative to the cardiac cycle, which can be disrupted by dysrhythmias. Administering antiarrhythmic medications or defibrillation may also be necessary, but these are secondary steps. Simply increasing the pump frequency without addressing the timing would not resolve the issue and may worsen the patient's hemodynamic status.

In pediatric trauma, the primary survey follows the ABCDE (Airway, Breathing, Circulation, Disability, Exposure) sequence. Gurgling respirations indicate a partially obstructed airway, which is an immediate life threat that must be addressed first. While the patient also shows signs of shock (tachycardia, pale/cool skin), establishing a patent airway is the priority. Without a clear airway, all other resuscitation efforts, such as fluid administration, will be ineffective. Therefore, suctioning the airway is the most critical initial intervention.

Magnesium sulfate is the first-line treatment for eclampsia-associated seizures during pregnancy. It has been proven to be effective in controlling seizures and preventing recurrence. It is important to differentiate this from other medications like diazepam and lorazepam, which are used for general seizure control but are not the primary drugs of choice for eclampsia.

The most appropriate initial intervention for suspected abdominal compartment syndrome (ACS) is decompression of the abdomen, ideally through surgical means. While managing the patient's blood pressure and respiratory status are also critical, decompression directly addresses the underlying issue causing the symptoms of ACS. Administering fluids or vasopressors alone may not be sufficient to relieve the increased intra-abdominal pressure.

Immersing the frostbitten areas in warm water is the correct approach because it helps to gently rewarm the tissues, which is crucial for minimizing further damage. Rubbing frostbitten areas can cause additional injury due to ice crystals in the tissue. Removing blisters is not recommended as it can lead to infection. Applying direct heat, like a heating pad, can cause burns due to the patient's decreased sensation.

The presence of hypotension, tachycardia, and abdominal distension combined with Grey Turner's sign suggests retroperitoneal hemorrhage. This is a serious condition that can result from blunt abdominal trauma. The other potential answers are not accompanied by these specific clinical signs. Splenic rupture typically presents with left upper quadrant pain and possible referred pain to the left shoulder (Kehr's sign). Hollow organ injury might present with signs of peritonitis but not specifically with Grey Turner's sign. Diaphragmatic rupture may show respiratory distress or bowel sounds in the chest, but not the signs described in this scenario.

According to the most recent Advanced Trauma Life Support (ATLS) guidelines, the initial management for hemorrhagic shock may begin with a judicious bolus of a warmed isotonic crystalloid solution, such as Lactated Ringer's or normal saline. This is considered a temporizing measure. The modern standard of care, known as Damage Control Resuscitation (DCR), emphasizes minimizing crystalloid administration to avoid dilutional coagulopathy, hypothermia, and acidosis. The primary goal is to transition rapidly to hemostatic resuscitation with blood products (packed red blood cells, plasma, and platelets) in a balanced ratio. While packed red blood cells are essential, they are part of the subsequent balanced resuscitation strategy, not typically the very first fluid administered in isolation. Hypertonic saline may be considered for patients with concurrent traumatic brain injury but is not the primary choice for hemorrhage alone. Colloids like albumin are not a first-line choice in initial trauma resuscitation.

The most immediate management priority for patients with significant midline shift due to a space-occupying lesion, such as intraparenchymal hemorrhage, is to ensure adequate oxygenation and ventilation, as increased intracranial pressure (ICP) can compromise respiratory function. Hyperventilation can help reduce ICP by causing cerebral vasoconstriction. Ensuring airway patency and oxygenation are critical during transport to prevent secondary brain injury. While monitoring blood pressure and administering osmotic diuretics are important, ensuring adequate ventilation takes precedence to avoid further hypoxia or hypercapnia which can exacerbate neurological deterioration.

Setting the tidal volume is crucial when initiating invasive ventilation in ARDS patients because using too high a tidal volume can cause ventilator-induced lung injury (VILI). Keeping the tidal volume at 6 mL/kg of predicted body weight helps to minimize this risk. While positive end-expiratory pressure (PEEP), respiratory rate, and FiO2 are also important settings, they do not directly correlate with lung injury prevention as effectively as tidal volume management.

The combination of markedly greater motor weakness in the upper than in the lower extremities, sensory loss predominantly affecting pain and temperature, preserved proprioception, and a hyper-extension cervical mechanism is classic for central cord syndrome. Central cord injuries involve the central corticospinal tracts that contain fibers for the arms situated more medially, producing the characteristic arm-dominant motor deficit. Anterior cord syndrome causes bilateral motor and pain/temperature loss below the lesion with preserved dorsal-column sensation; Brown-Sequard syndrome produces ipsilateral motor loss with contralateral pain/temperature loss; cauda equina syndrome involves lower-motor-neuron leg weakness and saddle anesthesia.

As the helicopter ascends, ambient barometric pressure falls. According to Boyle's law, any intracranial air pocket (post-traumatic or post-operative pneumocephalus) expands as external pressure drops. The rigid skull cannot accommodate this volume increase, so ICP rises. Altitude-induced hypoxia further promotes cerebral vasodilation and edema, compounding the pressure elevation. Acceleration forces, sympathetic stimulation from noise/vibration, or equipment activation do not directly raise ICP to the same degree. Hypercarbia would increase ICP but was ruled out by stable ventilator settings and end-tidal CO₂.

The most appropriate initial treatment for a patient with a blood glucose reading of 35 mg/dL is IV administration of dextrose. This approach rapidly increases blood glucose levels, which is critical in an unconscious patient. While a glucagon injection can also raise blood glucose, it is usually used in settings where IV access is not available. Oral glucose gels cannot be administered to unconscious patients due to the risk of aspiration.

The most crucial initial step in stabilizing a patient with a suspected spinal cord injury is maintaining proper immobilization techniques to prevent further spinal damage. Manual in-line stabilization minimizes movement of the spine and helps avoid exacerbating the injury. Administering IV fluids and monitoring neurological status are essential but secondary measures following proper immobilization.