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CTRN practice questions

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Question 1Patient Assessment and Monitoring

Which resting respiratory rate is normal for a healthy adult?

  1. 12 to 20 breaths/min Correct answer.
  2. 6 to 10 breaths/min
  3. 30 to 36 breaths/min
  4. 22 to 28 breaths/min

Explanation

A normal adult resting respiratory rate is 12 to 20 breaths per minute. Rates below 12 are bradypnea, and rates above 20 are tachypnea.

Question 2Patient Assessment and Monitoring

Which mean arterial pressure range is generally considered normal for an adult?

  1. 150 to 180 mm Hg
  2. 40 to 60 mm Hg
  3. 70 to 100 mm Hg Correct answer.
  4. 110 to 140 mm Hg

Explanation

A mean arterial pressure of roughly 70 to 100 mm Hg is normal for an adult. A MAP below 65 mm Hg suggests inadequate organ perfusion.

Question 3Patient Assessment and Monitoring

What is the highest possible Glasgow Coma Scale score?

  1. 12
  2. 10
  3. 15 Correct answer.
  4. 20

Explanation

The Glasgow Coma Scale ranges from 3 to 15, with 15 representing the best possible score. It is the sum of eye, verbal, and motor scores.

Question 4Patient Assessment and Monitoring

Which pain assessment tool is most appropriate for an adult who cannot self-report pain?

  1. Numeric rating scale
  2. CPOT Correct answer.
  3. Wong-Baker FACES scale
  4. Visual analog scale

Explanation

The Critical-Care Pain Observation Tool uses behavioral and physiologic indicators and is designed for patients who cannot self-report. The numeric, FACES, and visual analog scales all require patient self-report.

Question 5Patient Assessment and Monitoring

Which breath sound is high-pitched, harsh, and normally heard over the trachea?

  1. Bronchial Correct answer.
  2. Vesicular
  3. Crackles
  4. Bronchovesicular

Explanation

Bronchial breath sounds are high-pitched and harsh and are normally heard over the trachea. Vesicular sounds are soft and low-pitched, and crackles are abnormal discontinuous sounds.

Question 6Patient Assessment and Monitoring

A patient has pinpoint, unreactive pupils. Which medication class most commonly produces this finding?

  1. Benzodiazepines
  2. Sympathomimetics
  3. Opioids Correct answer.
  4. Anticholinergics

Explanation

Opioids stimulate the pupillary constrictor pathway and commonly cause pinpoint pupils. Anticholinergics and sympathomimetics tend to dilate the pupils instead.

Question 7Patient Assessment and Monitoring

Which route provides the most accurate measurement of core body temperature?

  1. Pulmonary artery Correct answer.
  2. Oral
  3. Axillary
  4. Temporal artery

Explanation

Pulmonary artery temperature reflects the temperature of blood leaving the heart and is considered the most accurate core measurement. Oral, temporal, and axillary readings are more affected by environmental and site factors.

Question 8Patient Assessment and Monitoring

Which blood glucose value meets the definition of hypoglycemia in an adult?

  1. 180 mg/dL
  2. 100 mg/dL
  3. 60 mg/dL Correct answer.
  4. 120 mg/dL

Explanation

Hypoglycemia in an adult is generally defined as a blood glucose below 70 mg/dL. A value of 60 mg/dL is therefore hypoglycemic.

Question 9Patient Assessment and Monitoring

Which ECG finding indicates a third-degree (complete) heart block?

  1. P waves and QRS complexes occur independently of each other Correct answer.
  2. PR interval progressively lengthens until a beat is dropped
  3. QRS complexes are wide and preceded by a consistent P wave
  4. Every other P wave is followed by a QRS complex

Explanation

In complete heart block, atrial impulses do not conduct to the ventricles, so P waves and QRS complexes march out independently. This is called atrioventricular dissociation.

Question 10Patient Assessment and Monitoring

Which capnography finding most strongly suggests esophageal intubation?

  1. No measurable end-tidal CO2 Correct answer.
  2. A curare cleft pattern
  3. A shark-fin-shaped waveform
  4. A gradually rising baseline

Explanation

Esophageal placement produces no significant end-tidal CO2 because gas exchange does not occur in the esophagus. A sustained waveform confirms tracheal placement.

Question 11Patient Assessment and Monitoring

Which blood pressure set best illustrates the narrow pulse pressure seen in hemorrhagic shock?

  1. 88/76 mm Hg Correct answer.
  2. 100/70 mm Hg
  3. 140/90 mm Hg
  4. 120/80 mm Hg

Explanation

Pulse pressure is the difference between systolic and diastolic pressure. A reading of 88/76 mm Hg gives a pulse pressure of 12 mm Hg, which is narrowed and consistent with poor stroke volume in hemorrhagic shock.

Question 12Patient Assessment and Monitoring

Which finding is usually the earliest indicator of rising intracranial pressure?

  1. Bilateral fixed and dilated pupils
  2. Altered level of consciousness Correct answer.
  3. Decerebrate posturing in all extremities
  4. Cushing triad with bradycardia

Explanation

A change in level of consciousness is typically the earliest sign of increasing intracranial pressure. Pupillary changes, posturing, and Cushing triad occur later as herniation progresses.

Question 13Patient Assessment and Monitoring

Which three components make up the pediatric assessment triangle?

  1. Pulse rate, respiratory rate, and blood pressure
  2. Glasgow Coma Scale, pupil size, and posture
  3. Appearance, work of breathing, circulation to skin Correct answer.
  4. Airway patency, breathing, and circulatory status

Explanation

The pediatric assessment triangle is a rapid visual tool made up of appearance, work of breathing, and circulation to skin. It is completed before touching the child.

Question 14Patient Assessment and Monitoring

The shock index is calculated using which ratio?

  1. Mean arterial pressure divided by heart rate
  2. Systolic BP divided by heart rate
  3. Heart rate divided by systolic BP Correct answer.
  4. Heart rate divided by diastolic BP

Explanation

Shock index is heart rate divided by systolic blood pressure. A value above roughly 0.9 in an adult suggests occult shock.

Question 15Patient Assessment and Monitoring

An arterial blood gas shows pH 7.28, PaCO2 55 mm Hg, and HCO3 24 mEq/L. Which interpretation is correct?

  1. Metabolic acidosis
  2. Respiratory acidosis Correct answer.
  3. Mixed acid-base disorder
  4. Respiratory alkalosis

Explanation

The low pH indicates acidosis, and the elevated PaCO2 points to a respiratory cause. Because the bicarbonate is normal, there is no metabolic compensation.

Question 16Patient Assessment and Monitoring

Which finding is most consistent with a tension pneumothorax?

  1. Pleuritic chest pain with a friction rub
  2. Bilateral crackles with pink frothy sputum
  3. Diffuse wheezing with prolonged expiration
  4. Absent breath sounds on one side with shock Correct answer.

Explanation

Tension pneumothorax causes unilateral absent breath sounds, tracheal deviation, and obstructive shock. Immediate needle decompression is required.

Question 17Patient Assessment and Monitoring

Using the rule of nines in an adult, what percentage of total body surface area is the entire anterior trunk?

  1. 18% Correct answer.
  2. 9%
  3. 27%
  4. 36%

Explanation

In the adult rule of nines, the anterior trunk represents 18% of total body surface area. The posterior trunk also represents 18%.

Question 18Patient Assessment and Monitoring

During ground ambulance transport, which action best reduces motion artifact on the ECG tracing?

  1. Secure electrodes and limit patient motion Correct answer.
  2. Place electrodes over hairy chest areas
  3. Increase the monitor's gain setting
  4. Switch to a different lead without changing electrodes

Explanation

Motion artifact is reduced by ensuring good electrode adhesion and minimizing patient movement and cable traction. Increasing gain or changing leads without correcting the source does not solve the problem.

Question 19Patient Assessment and Monitoring

Which finding is a recognized predictor of difficult bag-mask ventilation in an adult?

  1. Mallampati class I airway
  2. Normal thyromental distance
  3. Full set of natural teeth
  4. Edentulous jaw Correct answer.

Explanation

An edentulous jaw is a recognized predictor of difficult mask ventilation because the mask seal is harder to maintain. Other predictors include obesity, age over 55, and a beard.

Question 20Patient Assessment and Monitoring

A central venous pressure reading of 2 mm Hg most likely indicates which condition?

  1. Hypovolemia Correct answer.
  2. Right heart failure
  3. Cardiac tamponade
  4. Tension pneumothorax

Explanation

Normal CVP is roughly 2 to 8 mm Hg, and a value at the low end suggests reduced venous return. In a hypotensive or volume-depleted patient, this supports hypovolemia.

Question 21Patient Assessment and Monitoring

Why can pulse oximetry readings fall during air medical transport at altitude?

  1. Hemoglobin saturation is unaffected by altitude
  2. Ambient light interferes more at altitude
  3. Inspired oxygen partial pressure decreases Correct answer.
  4. Pulse oximeters need recalibration at altitude

Explanation

As altitude increases, barometric pressure falls and the partial pressure of inspired oxygen decreases. This lowers alveolar and arterial oxygen tension, which can reduce SpO2.

Question 22Patient Assessment and Monitoring

A shark-fin appearance on the capnogram is most associated with which condition?

  1. Obstructive bronchospasm Correct answer.
  2. Hyperventilation
  3. Esophageal intubation
  4. Cuff leak around the tube

Explanation

A shark-fin waveform reflects a prolonged expiratory upstroke caused by airflow obstruction. It is commonly seen in bronchospasm or chronic obstructive pulmonary disease.

Question 23Patient Assessment and Monitoring

Which arterial line finding indicates an overdamped waveform?

  1. A mean pressure that equals the systolic pressure
  2. A widened pulse pressure with a sharp systolic peak
  3. Loss of the dicrotic notch Correct answer.
  4. A systolic pressure that falls with inspiration

Explanation

Overdamping blunts the waveform, lowers the systolic reading, raises the diastolic reading, and removes the dicrotic notch. Common causes include air bubbles, kinks, and clot in the tubing.

Question 24Patient Assessment and Monitoring

A trauma patient has a Glasgow Coma Scale score of 8 and unequal pupils. Which action is most appropriate?

  1. Obtain a repeat GCS in one hour
  2. Prepare for emergency intubation Correct answer.
  3. Give a bolus of hypotonic fluids
  4. Perform a lumbar puncture

Explanation

A GCS of 8 or less indicates a need to protect the airway, and unequal pupils suggest intracranial mass effect. Emergency intubation should be prepared while maintaining oxygenation and avoiding hypotension.

Question 25Patient Assessment and Monitoring

Which finding in a child is most concerning for compensated shock?

  1. Hypotension with a normal heart rate
  2. Prolonged capillary refill and tachycardia Correct answer.
  3. Hypertension with bounding peripheral pulses
  4. Bradycardia with a widened pulse pressure

Explanation

Children maintain blood pressure until shock is advanced, so tachycardia and prolonged capillary refill are early signs of compensated shock. Hypotension is a late and ominous finding.

Question 26Patient Assessment and Monitoring

During a rapid peripheral perfusion assessment on an adult, which technique is correct for measuring capillary refill in a finger?

  1. Squeeze the fingertip until the patient reports discomfort and note blanching
  2. Press the nail bed firmly for 5 seconds, release, and time color return Correct answer.
  3. Press lightly over the radial artery for 10 seconds and watch the palm
  4. Occlude the radial artery for 30 seconds and time the pulse return

Explanation

Capillary refill is assessed by blanching the nail bed with firm pressure for about 5 seconds, then releasing and timing how quickly color returns; a normal result is under 2 seconds. Prolonged refill suggests peripheral vasoconstriction or poor perfusion, although ambient temperature and age can affect the reading.

Question 27Patient Assessment and Monitoring

A patient's blood pressure is 100/60 mm Hg. Which value represents the mean arterial pressure?

  1. 73 mm Hg Correct answer.
  2. 60 mm Hg
  3. 80 mm Hg
  4. 87 mm Hg

Explanation

Mean arterial pressure can be estimated as diastolic pressure plus one third of the pulse pressure: the pulse pressure here is 40 mm Hg, one third is about 13, giving approximately 73 mm Hg. The same value comes from (SBP + 2 x DBP) / 3. MAP is used to estimate organ perfusion, and many resuscitation protocols target at least 65 mm Hg.

Question 28Patient Assessment and Monitoring

During a blood pressure measurement on a patient with suspected cardiac tamponade, the systolic pressure falls from 118 mm Hg to 104 mm Hg during inspiration. Which term describes this finding?

  1. Pulsus alternans
  2. Electrical alternans
  3. Orthostatic hypotension
  4. Pulsus paradoxus Correct answer.

Explanation

Pulsus paradoxus is an inspiratory fall in systolic pressure greater than 10 mm Hg, and this patient's 14 mm Hg drop meets that threshold. It reflects exaggerated ventricular interdependence and is classically associated with cardiac tamponade, tension pneumothorax, and severe asthma.

Question 29Patient Assessment and Monitoring

Which change in vital signs on standing meets the usual criteria for a positive orthostatic test in an adult?

  1. A rise in heart rate of 5 beats/min
  2. A rise in systolic pressure of 15 mm Hg
  3. A fall in diastolic pressure of 5 mm Hg
  4. A fall in systolic pressure of 20 mm Hg Correct answer.

Explanation

A positive orthostatic test is conventionally a fall in systolic pressure of at least 20 mm Hg or a fall in diastolic pressure of at least 10 mm Hg within about 3 minutes of standing, often accompanied by a rise in heart rate. The finding suggests volume depletion or autonomic dysfunction and should be interpreted alongside symptoms such as dizziness.

Question 30Patient Assessment and Monitoring

A patient with a pulmonary artery catheter has a mixed venous oxygen saturation (SvO2) of 45%. Which interpretation is most likely?

  1. The value is normal for a resting adult
  2. Tissue oxygen extraction is increased Correct answer.
  3. Oxygen delivery exceeds tissue oxygen demand
  4. A left-to-right intracardiac shunt is present

Explanation

Mixed venous oxygen saturation reflects the balance between oxygen delivery and consumption, with a normal range of roughly 60% to 75%. A value of 45% indicates that tissues are extracting a larger fraction of delivered oxygen, as seen with low cardiac output, anemia, hypoxemia, or increased metabolic demand.

Question 31Airway, Ventilation, and Oxygenation

A spontaneously breathing adult in severe respiratory distress requires the highest possible inspired oxygen concentration during transport. Which device should be applied at 15 L/min?

  1. Nonrebreather mask at 15 L/min Correct answer.
  2. Nasal cannula at 6 L/min with humidification
  3. Venturi mask titrated to a fixed 24% concentration
  4. Simple face mask at 5 L/min with a reservoir bag

Explanation

A nonrebreather mask with a reservoir bag and a tight seal at 15 L/min delivers an FiO2 of roughly 80% to 95% because the reservoir supplies each breath before room air entrainment occurs. Simple masks generally reach only 40% to 60%, and nasal cannula flow cannot exceed about 44% even at maximum rates.

Question 32Airway, Ventilation, and Oxygenation

In an adult, approximately how much does each liter per minute of nasal cannula flow increase the delivered oxygen concentration?

  1. 10%
  2. 21%
  3. 1%
  4. 4% Correct answer.

Explanation

The accepted rule of thumb is that each liter per minute adds about 4% above the 21% of room air, so 6 L/min yields roughly 45%. Higher flows do not reliably increase FiO2 further because the nasopharynx cannot entrain additional oxygen.

Question 33Airway, Ventilation, and Oxygenation

Which condition is most likely to produce a falsely low pulse oximetry reading?

  1. Severe anemia with a normal arterial oxygen tension
  2. Carbon monoxide poisoning
  3. Sickle cell trait with normal hemoglobin
  4. Cold, clammy extremities with poor perfusion Correct answer.

Explanation

Pulse oximetry depends on detecting a pulsatile arterial signal, so vasoconstriction and poor peripheral flow degrade the signal and can produce falsely low or unobtainable readings. Carboxyhemoglobin actually reads falsely high because it absorbs light similarly to oxyhemoglobin. Anemia reduces oxygen content but not the percentage saturation the device measures.

Question 34Airway, Ventilation, and Oxygenation

When bag-mask ventilating an adult during transport, which approach best avoids gastric insufflation?

  1. Just enough to produce visible chest rise Correct answer.
  2. A volume that produces an audible squeak at the mask
  3. 1500 mL with each squeeze
  4. The largest volume the bag will deliver

Explanation

Adult bag-mask ventilation should deliver roughly 500 to 600 mL, judged by a gentle squeeze that produces visible chest rise over about one second. Larger volumes raise airway pressure above the esophageal opening pressure, forcing air into the stomach and increasing aspiration risk.

Question 35Airway, Ventilation, and Oxygenation

Which capnography finding most strongly suggests that an endotracheal tube has been placed in the esophagus?

  1. A gradual rise in end-tidal CO2 over 5 minutes
  2. A rectangular waveform with a steep upstroke
  3. No CO2 waveform after several ventilations Correct answer.
  4. End-tidal CO2 of 35 mm Hg that persists over time

Explanation

Esophageal placement produces no alveolar CO2 to exhale, so waveform capnography fails to register a value after several breaths. Persistent CO2 across multiple ventilations is the most reliable confirmation of tracheal placement.

Question 36Airway, Ventilation, and Oxygenation

Which history makes succinylcholine unsafe for rapid sequence intubation?

  1. Chronic kidney disease with a normal serum potassium
  2. A history of well-controlled asthma
  3. Essential hypertension treated with a beta blocker
  4. A major burn sustained 10 days ago Correct answer.

Explanation

Upregulation of extrajunctional acetylcholine receptors after major burns, crush injury, or denervation causes a exaggerated potassium efflux with succinylcholine, risking fatal hyperkalemia. The risk begins roughly 24 to 48 hours after the injury and persists for months.

Question 37Airway, Ventilation, and Oxygenation

A Mallampati class III airway assessment describes which finding?

  1. Only the hard palate is visible
  2. The uvula, fauces, and soft palate are all visible
  3. Only the soft palate and uvula base are seen Correct answer.
  4. The soft palate, fauces, and part of the uvula are visible

Explanation

Mallampati class III means the soft palate and only the base of the uvula are visible while the fauces are obscured, which predicts a more difficult laryngoscopy. Class I shows the full uvula, fauces, and pillars, class II shows the uvula and fauces, and class IV shows only the hard palate.

Question 38Airway, Ventilation, and Oxygenation

A ventilated patient has a peak airway pressure of 48 cm H2O with a plateau pressure of 20 cm H2O. Which problem does this pattern indicate?

  1. Decreased chest wall compliance from abdominal distension
  2. Increased airway resistance from bronchospasm Correct answer.
  3. Decreased lung compliance from pulmonary edema
  4. A developing pneumothorax with reduced compliance

Explanation

The gradient between peak and plateau pressure reflects resistive pressure losses in the airways. A wide gradient with a normal plateau points to bronchospasm, secretions, a kinked tube, or tube obstruction rather than to a problem with lung or chest wall compliance.

Question 39Airway, Ventilation, and Oxygenation

What is the primary physiologic effect of applying positive end-expiratory pressure?

  1. Increasing venous return to the right heart
  2. Recruiting collapsed alveoli Correct answer.
  3. Reducing functional residual capacity
  4. Lowering mean airway pressure during each breath

Explanation

PEEP holds alveoli open at end expiration, recruiting collapsed units and preventing cyclic opening and closing that injures lung tissue. It improves oxygenation by reducing shunt but also raises intrathoracic pressure.

Question 40Airway, Ventilation, and Oxygenation

A patient has received an FiO2 of 1.0 for more than 24 hours. Which complication is most directly related to this exposure?

  1. Methemoglobinemia from nitrogen displacement
  2. Absorptive atelectasis and oxidative lung injury Correct answer.
  3. Hypercapnia from increased physiologic dead space
  4. Carbon dioxide narcosis

Explanation

High inspired oxygen washes nitrogen out of alveoli, which then collapse when oxygen is absorbed faster than it is replaced, and sustained hyperoxia generates reactive oxygen species that injure alveolar epithelium. The goal is to wean to the lowest FiO2 that maintains the target saturation.

Question 41Airway, Ventilation, and Oxygenation

Which practice reduces complications during endotracheal suctioning?

  1. Instilling 10 mL of normal saline to loosen secretions
  2. Suctioning routinely every hour regardless of need
  3. Limiting each pass to 10-15 seconds with preoxygenation Correct answer.
  4. Applying continuous suction while inserting the catheter

Explanation

Each suction pass should last no more than about 10 to 15 seconds and be preceded by hyperoxygenation, because suctioning removes oxygen and can cause hypoxemia, atelectasis, and vagally mediated bradycardia. Suction should be applied only during withdrawal.

Question 42Airway, Ventilation, and Oxygenation

A patient with a tracheostomy placed three days ago develops increasing resistance to ventilation. What is the most appropriate initial action?

  1. Instill 10 mL of saline into the tube and wait 5 minutes
  2. Immediately remove the tracheostomy tube and leave the stoma open
  3. Inflate the cuff to a higher pressure to seal the leak
  4. Suction the tube, then remove the inner cannula if needed Correct answer.

Explanation

Suctioning is the first step for suspected mucus plugging, and a removable inner cannula can then be taken out and either cleaned or replaced to restore a patent lumen. Attempting to reinsert a tube through a stoma less than about seven days old is hazardous because the tract is not yet formed.

Question 43Airway, Ventilation, and Oxygenation

An arterial blood gas shows pH 7.22, PaCO2 60 mm Hg, and HCO3 25 mEq/L. How should this be interpreted?

  1. Mixed metabolic and respiratory alkalosis
  2. Metabolic acidosis with respiratory compensation
  3. Chronic respiratory acidosis with metabolic compensation
  4. Acute respiratory acidosis Correct answer.

Explanation

An acid pH with an elevated PaCO2 identifies respiratory acidosis, and a bicarbonate near the normal upper limit indicates no metabolic compensation has occurred yet. That combination is acute; chronic retention would produce a bicarbonate well above normal.

Question 44Airway, Ventilation, and Oxygenation

Which cause of hypoxemia responds least to supplemental oxygen?

  1. Diffusion impairment across a thickened alveolar membrane
  2. Alveolar hypoventilation from opioid sedation
  3. Ventilation-perfusion mismatch
  4. A large right-to-left intracardiac shunt Correct answer.

Explanation

Blood that bypasses the alveoli through a true right-to-left shunt never contacts inspired oxygen, so raising FiO2 cannot correct the resulting hypoxemia. The other mechanisms involve underventilated but still communicating alveoli, which respond to a higher inspired concentration.

Question 45Airway, Ventilation, and Oxygenation

A mechanically ventilated patient with severe asthma has rising peak pressures and an expiratory flow tracing that does not return to baseline before the next breath. Which ventilator change is most appropriate?

  1. Increasing the tidal volume to improve recruitment
  2. Increasing PEEP to overcome the auto-PEEP
  3. Increasing the respiratory rate to improve minute ventilation
  4. Decreasing the set respiratory rate Correct answer.

Explanation

Failure of expiratory flow to reach baseline signals air trapping and dynamic hyperinflation. Slowing the respiratory rate lengthens expiratory time, allowing complete exhalation and reducing the risk of barotrauma and hypotension from impaired venous return.

Question 46Airway, Ventilation, and Oxygenation

A full H cylinder contains 6900 L of oxygen at 2200 psi. The gauge reads 1100 psi, and the patient is receiving 10 L/min. Approximately how long will the cylinder last?

  1. About 1.5 hours
  2. About 5.8 hours Correct answer.
  3. About 2.9 hours
  4. About 11.5 hours

Explanation

Remaining volume equals 6900 L multiplied by 1100/2200, or 3450 L. Dividing by a 10 L/min flow gives 345 minutes, which is approximately 5.75 hours.

Question 47Airway, Ventilation, and Oxygenation

Which dose of rocuronium is recommended for rapid sequence intubation to achieve intubating conditions comparable to succinylcholine?

  1. 1.2 mg/kg Correct answer.
  2. 0.3 mg/kg
  3. 0.6 mg/kg
  4. 0.1 mg/kg

Explanation

Rocuronium 1.2 mg/kg provides paralysis within about 60 seconds and is the accepted alternative to succinylcholine for rapid sequence intubation. The 0.6 mg/kg intubating dose has an onset closer to two to three minutes, which is too slow for an emergency airway.

Question 48Airway, Ventilation, and Oxygenation

In pressure-control ventilation, which statement about delivered tidal volume is accurate?

  1. The mode cannot be combined with spontaneous breaths
  2. Peak pressure varies widely with each breath
  3. Tidal volume is fixed by a set ventilator parameter
  4. Volume varies with resistance and compliance Correct answer.

Explanation

Pressure-control ventilation holds a set inspiratory pressure, so the resulting tidal volume depends on the patient's airway resistance and lung compliance. Clinicians must monitor exhaled volume closely because worsening compliance will silently reduce tidal volume.

Question 49Airway, Ventilation, and Oxygenation

How is the correct size of an oropharyngeal airway determined in an adult?

  1. Runs from the mouth corner to the jaw angle Correct answer.
  2. Equals the diameter of the patient's little finger
  3. Reaches from the chin to the sternal notch with the head extended
  4. Extends from the nostril to the earlobe when laid alongside the face

Explanation

An oropharyngeal airway is properly sized when the flange sits at the corner of the mouth and the tip reaches the angle of the mandible. A device that is too long can push the tongue backward or provoke laryngospasm, while one that is too short is ineffective.

Question 50Airway, Ventilation, and Oxygenation

Which oxygen saturation target applies to most acutely ill adults receiving supplemental oxygen?

  1. 80-85% to prevent hyperoxia
  2. 88-92% for all adults regardless of history
  3. 94-98% Correct answer.
  4. 100% whenever it can be achieved safely

Explanation

Guidelines recommend targeting a saturation of about 94% to 98% in most acutely ill adults, avoiding both hypoxemia and unnecessary hyperoxia. A lower target of 88% to 92% is reserved for patients at risk of hypercapnic respiratory failure.