Preguntas de práctica CEN

• A. A patient with new weakness on one side and slurred speech, with a stable airway
• B. An unresponsive patient with no pulse
• C. A patient with abdominal pain who will need blood tests, imaging and IV fluids
• D. A patient with a small cut that needs one simple procedure

Respuesta: B. An unresponsive patient with no pulse

ESI level 1 is for patients who need an immediate life-saving intervention, and a person with no pulse is the clearest example. The stroke presentation is high risk and fits level 2, because the patient is unstable in a time-critical way but not yet needing a rescue at the door. Abdominal pain that will use several resources is level 3, and a problem needing one resource is level 4. Level 5 needs none. Triage sorts by how sick the patient is and how many resources they will use, not by who arrived first.

• A. The airway is open for now, and it still has to be reassessed
• B. The airway can be ruled out as a problem for the whole visit
• C. Breathing and circulation are both normal
• D. Neurologic function is normal

Respuesta: A. The airway is open for now, and it still has to be reassessed

A patient who speaks clearly has a patent airway and enough air movement to talk, which is a good sign. It is only a snapshot, though, because swelling, bleeding and a falling level of consciousness can close an airway later, so the airway is checked again as the patient changes. Talking says nothing about the rate or depth of breathing, about circulation or about the whole neurologic exam, which each have their own step in the survey.

• A. Tension pneumothorax
• B. A small pleural effusion
• C. Pulmonary embolism
• D. Pericarditis

Respuesta: A. Tension pneumothorax

In a tension pneumothorax air enters the pleural space and cannot leave, so pressure builds, the lung collapses and the mediastinum is pushed against the great veins. Venous return falls, which explains the distended neck veins together with the low blood pressure. Absent breath sounds on the injured side with severe distress is the classic picture. Tracheal deviation away from the injury is real but late, so waiting for it can mean missing the diagnosis. A small effusion would not drop the pressure, and an embolus or pericarditis would not give one-sided absent breath sounds after trauma.

By the rule of nines, the front of an adult's trunk is about _____ percent of the body surface and each entire arm is about _____ percent.

Opciones para el hueco 1: 9, 18, 36

Opciones para el hueco 2: 9, 18, 4.5

Respuesta: 18, 9

The rule of nines splits an adult's body surface into regions worth 9 percent or a multiple of it: the head 9, each arm 9, the front of the trunk 18, the back of the trunk 18, each leg 18 (front 9, back 9) and the groin 1. It gives a fast estimate of burn size that sets the triage level and the transfer decision. It is less accurate in children, whose heads are proportionally larger, so pediatric charts adjust the numbers. Only partial and full thickness burns are counted, not simple redness.

• A. Carbon monoxide raises the oxygen dissolved in the plasma
• B. The probe cannot detect hemoglobin at all in smoke exposure
• C. It reads carboxyhemoglobin much like oxyhemoglobin
• D. Carbon monoxide makes the fingers warmer, which skews the reading

Respuesta: C. It reads carboxyhemoglobin much like oxyhemoglobin

A standard pulse oximeter compares only two wavelengths of light, and carboxyhemoglobin absorbs light in a way the device cannot tell apart from oxyhemoglobin. The screen can therefore look fine while much of the hemoglobin is occupied by carbon monoxide and cannot carry oxygen. That is why symptoms, history and a co-oximetry blood gas matter more than the number on the finger probe in suspected exposure.

• A. Blockage of acetylcholine receptors at the muscle
• B. Release of large amounts of norepinephrine
• C. Direct damage to the red blood cells
• D. Inhibition of the enzyme that breaks down acetylcholine

Respuesta: D. Inhibition of the enzyme that breaks down acetylcholine

Organophosphate pesticides block acetylcholinesterase, so acetylcholine keeps stimulating its targets. The result is a cholinergic picture: secretions from every gland, small pupils, a slow heart rate and twitching or weakness of muscle. Dry skin, wide pupils and a fast heart rate would point the other way, to an anticholinergic exposure. Exposure through skin counts too, which is why the history of what the person was handling matters.

• A. Heavy sweating
• B. Painful muscle cramps
• C. Thirst and headache
• D. Confusion or a changed level of consciousness with a very high core temperature

Respuesta: D. Confusion or a changed level of consciousness with a very high core temperature

In heat exhaustion the body is still coping: the patient sweats, feels weak and thirsty and may have cramps, but thinking stays largely intact. Heat stroke means the cooling system has failed, the core temperature is usually above about 104 F (40 C), and the brain shows it through confusion, odd behavior, seizures or coma. Skin can be wet or dry in either condition, so skin alone is not the deciding sign. A changed mental status in the heat is treated as heat stroke until proven otherwise.

• A. The patient is compensating, and the narrow pulse pressure is an early warning
• B. The patient is not in shock because the blood pressure is normal
• C. The patient is in neurogenic shock because the skin is cool
• D. The patient is anxious, and the vital signs have no clinical meaning

Respuesta: A. The patient is compensating, and the narrow pulse pressure is an early warning

In early blood loss the body clamps down its vessels and speeds the heart to hold the pressure up, so the systolic pressure can stay normal while the patient is already in trouble. A rising heart rate, cool clammy skin, anxiety and a pulse pressure that narrows (here 20, because the diastolic pressure climbs) are the early clues. A drop in blood pressure comes late, after large losses. Neurogenic shock gives warm, dry skin and often a slow heart rate, not a fast one.

• A. Loss of the radial pulse
• B. Pain out of proportion to the injury that worsens with passive stretch of the muscles
• C. Pale skin
• D. Paralysis of the fingers

Respuesta: B. Pain out of proportion to the injury that worsens with passive stretch of the muscles

Swelling inside a closed muscle compartment raises the pressure until the small vessels and nerves are squeezed. Severe pain that does not match the injury, and that gets worse when the muscles are stretched, appears first. Pulse loss, pallor and paralysis are late, because the pressure has to exceed arterial pressure before the pulse goes. Waiting for a missing pulse means the tissue has already been without blood for some time, so the early pain finding is the one to catch.

• A. Epididymitis, because it can spread to the other side within an hour
• B. Testicular torsion, because the blood supply is cut off and tissue can be lost within hours
• C. A hydrocele, because it can burst without warning
• D. A urinary stone, because it always causes pain in the testis alone

Respuesta: B. Testicular torsion, because the blood supply is cut off and tissue can be lost within hours

Torsion twists the spermatic cord and cuts off the blood supply, so the testis is at risk of dying and the chance of saving it falls over a matter of hours. Sudden onset, nausea, a high-riding testis and a lost cremasteric reflex are the typical signs. Epididymitis tends to start more gradually, often with fever or urinary symptoms, and the pain may ease when the scrotum is lifted. A hydrocele is usually painless, and a stone causes flank pain that can spread but has a different pattern.

Marca todas las que correspondan.

• A. Sudden weakness of one arm
• B. A drooping face on one side
• C. A brief gray-out when standing up, gone within a minute of lying down
• D. Speech that is suddenly slurred or hard to find
• E. Dizziness after standing in a hot room for a long time

Respuesta: A. Sudden weakness of one arm, B. A drooping face on one side, D. Speech that is suddenly slurred or hard to find

Stroke strikes a part of the brain, so the signs are focal: one side of the body, one side of the face or speech. They do not clear in a minute. Fainting, in contrast, comes from a short drop in blood flow to the whole brain, usually when standing up or after heat or a long wait, and recovery is quick and complete once the person is lying flat. Whatever the cause, the time the patient was last known to be normal is the most important fact to establish, because treatment choices depend on it.

Marca todas las que correspondan.

• A. A respiratory rate above 30 per minute
• B. Capillary refill longer than 2 seconds
• C. Unable to follow a simple command
• D. Able to walk to the designated area
• E. Not breathing even after the airway is opened

Respuesta: A. A respiratory rate above 30 per minute, B. Capillary refill longer than 2 seconds, C. Unable to follow a simple command

START (Simple Triage and Rapid Treatment) sorts patients in seconds by walking, breathing, perfusion and mental status. A fast respiratory rate, poor perfusion (slow capillary refill or no radial pulse) or an inability to follow commands each mark an immediate patient. Anyone who can walk goes to the minor group first. A patient who is not breathing after the airway is opened is tagged expectant or deceased in START, not immediate. Systems differ, and some regions use SALT, so know what your own jurisdiction and your exam materials teach.

Marca todas las que correspondan.

• A. It stops cells from using oxygen at the mitochondria
• B. It works by stopping hemoglobin from carrying oxygen
• C. Smoke from an enclosed fire can be a source
• D. The lactate level usually rises
• E. It causes cholinergic excess, with heavy salivation and tearing

Respuesta: A. It stops cells from using oxygen at the mitochondria, C. Smoke from an enclosed fire can be a source, D. The lactate level usually rises

Cyanide blocks cytochrome oxidase, the last step of the energy chain in the mitochondria, so cells cannot use the oxygen that reaches them. They switch to anaerobic metabolism, which makes lactate, and the blood can stay oxygen-rich because the tissues are not taking it up. Burning plastics, wool and other materials in an enclosed space can release hydrogen cyanide, so it is considered in smoke inhalation. Carbon monoxide, not cyanide, interferes with hemoglobin, and cholinergic excess belongs to organophosphates.

The shock index is the heart rate divided by the _____ blood pressure, and a value above about _____ raises concern for shock.

Opciones para el hueco 1: diastolic, systolic, mean arterial

Opciones para el hueco 2: 0.4, 1.0, 2.5

Respuesta: systolic, 1.0

A normal shock index is roughly 0.5 to 0.7. In early blood loss the heart rate climbs before the systolic pressure falls, so the ratio rises while the blood pressure alone still looks acceptable. A heart rate of 120 with a systolic pressure of 100 gives 1.2. Sources set the cutoff between about 0.9 and 1.0, and the index is a screening aid that supports clinical judgment, never a replacement for it.

The Glasgow Coma Scale adds up eye, verbal and motor responses, so the lowest possible total is _____, and a total of _____ or less is generally treated as a severe head injury.

Opciones para el hueco 1: 0, 1, 3

Opciones para el hueco 2: 5, 8, 12

Respuesta: 3, 8

The eye score runs 1 to 4, the verbal score 1 to 5 and the motor score 1 to 6, so the lowest total is 3 and the highest is 15. A total of 8 or less is generally classed as severe, 9 to 12 as moderate and 13 to 15 as mild. The scale is the usual way to describe the disability step of the primary survey, and the three parts matter as much as the total, because the same total can come from quite different combinations.