Free Respiratory Therapist mock test

Respiratory Therapist sample questions with answers

10 more original exam-style Respiratory Therapist questions, worked in full. They are not real or recalled exam questions, and none of them is in the mock above or on the bank page, so sit the mock first if you have not.

1. Question 1 · Patient Assessment & Clinical Data Evaluation

   A patient with a COPD exacerbation on 4 L/min nasal cannula is using accessory muscles and is drowsy but rousable and able to protect the airway. Arterial blood gases show pH 7.25, PaCO2 78 mmHg, HCO3- 33 mEq/L, PaO2 62 mmHg. What should the therapist recommend?

   1. AIncrease the nasal cannula flow to 6 L/min and repeat gases in one hour
   2. BInitiate non-invasive positive pressure ventilation with bilevel support
   3. CProceed directly to intubation and controlled mechanical ventilation
   4. DAdd a continuous salbutamol nebulization and take no other action
   Show answer and explanation

   Correct answer: B. Initiate non-invasive positive pressure ventilation with bilevel support

   This is acute-on-chronic hypercapnic respiratory failure with a pH below 7.35, the strongest evidence-based indication for bilevel non-invasive ventilation, which reduces intubation rate and mortality in COPD exacerbation. Increasing oxygen flow worsens hypercapnia, immediate intubation is not required in a rousable patient who can protect the airway and cooperate, and bronchodilator therapy alone will not correct the ventilatory failure.

   Reference: ERS/ATS Clinical Practice Guidelines: Noninvasive Ventilation for Acute Respiratory Failure (European Respiratory Journal, 2017); GOLD Report 2024

2. Question 2 · Arterial Blood Gases, Acid-Base Balance & Oxygenation Assessment

   An adolescent presents with tinnitus, vomiting and hyperpnoea after a large aspirin ingestion. ABG and chemistry: pH 7.44, PaCO2 22 mmHg, HCO3- 15 mEq/L, Na+ 140 mEq/L, Cl- 102 mEq/L. What is the most accurate interpretation?

   1. APure primary respiratory alkalosis with renal compensation
   2. BPure high anion gap metabolic acidosis with maximal respiratory compensation
   3. CCompensated metabolic alkalosis
   4. DMixed primary respiratory alkalosis and high anion gap metabolic acidosis
   Show answer and explanation

   Correct answer: D. Mixed primary respiratory alkalosis and high anion gap metabolic acidosis

   The anion gap is 140 - (102 + 15) = 23 mEq/L, confirming an organic acidosis, yet Winter's formula predicts a PaCO2 of (1.5 x 15) + 8 = 30.5 +/- 2 mmHg while the measured PaCO2 is only 22, showing an additional primary respiratory alkalosis from direct medullary stimulation. A pure respiratory alkalosis would not raise the anion gap, compensation alone cannot drive PaCO2 below the predicted range, and the pH pattern is not alkalotic from a bicarbonate excess.

   Reference: Goldfrank's Toxicologic Emergencies, 11th ed., 2019; Egan's Fundamentals of Respiratory Care, 12th ed., 2021

3. Question 3 · Pulmonary Function Testing, Diagnostic Procedures & Chest Imaging

   A sleep technologist asks whether a diagnostic study may be converted to a split-night protocol. Which condition best supports doing so?

   1. AAn AHI of 8 per hour recorded during the first hour of the study
   2. BAn AHI of at least 40 per hour documented during at least 2 hours of diagnostic recording, with at least 3 hours remaining for titration
   3. CAny degree of snoring with oxygen desaturation below 94%
   4. DPatient preference to avoid returning for a second night, regardless of the recorded AHI
   Show answer and explanation

   Correct answer: B. An AHI of at least 40 per hour documented during at least 2 hours of diagnostic recording, with at least 3 hours remaining for titration

   Accepted split-night criteria require severe disease to be established early, conventionally an AHI of 40 or more over at least 2 hours of diagnostic recording (or 20 to 40 with supporting clinical judgement), plus at least 3 hours left to titrate positive airway pressure adequately across body positions and REM sleep. An AHI of 8 is only mild disease and does not justify abandoning the diagnostic study. Snoring with minor desaturation and patient convenience alone are not acceptable grounds, because an inadequate titration leads to an unreliable prescription.

   Reference: Kushida CA et al., AASM Practice Parameters for the Indications for Polysomnography, Sleep 2005; AASM Clinical Guidelines for the Manual Titration of Positive Airway Pressure, J Clin Sleep Med 2008

4. Question 4 · Airway Management & Artificial Airways

   Two minutes after an uneventful intubation for pneumonia-related hypoxemia, blood pressure falls from 118/70 to 74/40 mmHg. Breath sounds are equal, the trachea is midline, neck veins are flat, peak and plateau pressures are normal, and end-tidal CO2 is 34 mmHg with a normal waveform. What is the most likely explanation?

   1. ATension pneumothorax from barotrauma
   2. BRight mainstem intubation causing left lung collapse
   3. CAcute myocardial infarction caused by laryngoscopy
   4. DReduced venous return from positive pressure plus vasodilation from induction agents in a hypovolemic patient
   Show answer and explanation

   Correct answer: D. Reduced venous return from positive pressure plus vasodilation from induction agents in a hypovolemic patient

   Post-intubation hypotension is most commonly caused by the combination of induction-agent vasodilation and the fall in venous return that follows the switch from negative to positive pressure ventilation, especially in a septic or hypovolemic patient. Tension pneumothorax is excluded here by equal breath sounds, midline trachea, flat neck veins and normal plateau pressure. Right mainstem intubation would give asymmetric breath sounds and typically hypoxemia rather than isolated hypotension, and there is nothing pointing to acute infarction.

   Reference: Egan's Fundamentals of Respiratory Care, 12th edition, 2021 (Airway Management; Physiologic Effects of Positive Pressure Ventilation)

5. Question 5 · Airway Clearance, Lung Expansion & Pulmonary Rehabilitation

   A 3-day-old 28-week preterm infant with respiratory distress syndrome has a nurse requesting routine chest physiotherapy. What is the most appropriate response?

   1. ABegin percussion and vibration every four hours to prevent atelectasis
   2. BPerform vigorous head-down postural drainage twice daily
   3. CAdvise against routine chest physiotherapy, since it is not indicated for uncomplicated RDS and carries a risk of intraventricular haemorrhage and desaturation in this population
   4. DApply adult percussion cups at reduced force every six hours
   Show answer and explanation

   Correct answer: C. Advise against routine chest physiotherapy, since it is not indicated for uncomplicated RDS and carries a risk of intraventricular haemorrhage and desaturation in this population

   Chest physiotherapy has no established benefit in uncomplicated neonatal RDS, which is a surfactant deficiency rather than a secretion retention problem, and in very preterm infants it has been associated with hypoxaemia, bradycardia, rib injury and concern for intraventricular haemorrhage during the first days of life. Head-down positioning is avoided in neonates because of intracranial pressure and reflux risk. Adult-sized percussion equipment is inappropriate for a preterm chest, where a padded soft device or contact heel percussion would be used if therapy were indicated at all.

   Reference: AARC Clinical Practice Guideline: Postural Drainage Therapy (Respiratory Care, 1991; reaffirmed) and Cochrane review of chest physiotherapy for preterm infants (2016)

6. Question 6 · Critical Care, Emergency Response, Resuscitation & Transport

   Ten minutes after return of spontaneous circulation, a comatose adult is ventilated on FIO2 1.0 with SpO2 100% and PETCO2 24 mmHg. Blood pressure is 118/70 mmHg. What is the most appropriate respiratory management?

   1. AMaintain FIO2 1.0 for at least 12 hours to maximize oxygen delivery
   2. BIncrease the ventilator rate to keep PETCO2 near 20 mmHg for cerebral protection
   3. CTitrate FIO2 down to keep SpO2 approximately 92-98% and adjust ventilation to a normal PaCO2 of about 35-45 mmHg
   4. DChange to a spontaneous mode with CPAP 5 cmH2O to allow early neurologic assessment
   Show answer and explanation

   Correct answer: C. Titrate FIO2 down to keep SpO2 approximately 92-98% and adjust ventilation to a normal PaCO2 of about 35-45 mmHg

   Post-arrest care targets normoxemia (SpO2 92-98%) and normocapnia (PaCO2 35-45 mmHg), since both hyperoxia and hypocapnia worsen neurologic outcome; hypocapnia causes cerebral vasoconstriction and reduces cerebral blood flow. Prolonged FIO2 1.0 exposes the patient to unnecessary hyperoxic injury. A comatose post-arrest patient requires controlled ventilation and targeted temperature management, not immediate weaning to CPAP.

   Reference: American Heart Association Guidelines for CPR and ECC, Post-Cardiac Arrest Care (2020)

7. Question 7 · Mechanical Ventilation: Initiation, Management & Liberation

   A 34-year-old with viral ARDS remains at PaO2/FIO2 68 after 18 hours of proning, neuromuscular blockade, PEEP 16 and FIO2 1.0. Plateau pressure is 34 cmH2O and ABG shows pH 7.18, PaCO2 78 mmHg. What is the most appropriate next step?

   1. ABegin inhaled nitric oxide at 40 ppm as definitive rescue therapy
   2. BIncrease tidal volume to 10 mL/kg PBW to correct the respiratory acidosis
   3. CRefer urgently for veno-venous ECMO evaluation at an experienced centre
   4. DChange to high-frequency oscillatory ventilation as the standard rescue mode
   Show answer and explanation

   Correct answer: C. Refer urgently for veno-venous ECMO evaluation at an experienced centre

   Refractory hypoxemia with PaO2/FIO2 below 80, uncompensated hypercapnic acidosis and a plateau above 30 cmH2O despite proning and paralysis meets accepted EOLIA-style criteria for veno-venous ECMO referral. Inhaled nitric oxide gives only a transient oxygenation benefit, larger tidal volumes at an already excessive plateau would aggravate ventilator-induced lung injury, and HFOV has not shown benefit as routine rescue. Early referral before irreversible injury improves outcomes.

   Reference: Combes A et al., EOLIA, NEJM 378:1965 (2018); ELSO Guidelines for Adult Respiratory Failure (2021)

8. Question 8 · Patient Safety, Infection Prevention, Professionalism, Ethics & Scope of Practice

   A patient with irreversible multi-organ failure has had no neurological or haemodynamic improvement over three weeks of maximal support. The ICU team believes continued aggressive ventilation is physiologically futile, but the family insists that everything be continued. What is the most appropriate next step for the respiratory care team?

   1. AUnilaterally reduce ventilator support to a level the team considers appropriate without informing the family
   2. BComply with every family request indefinitely without further discussion, since the family holds decision-making authority
   3. CTell the family that the hospital policy prohibits further treatment and that support will be withdrawn tomorrow
   4. DContinue current support while requesting a structured goals-of-care meeting and, if disagreement persists, a formal ethics committee consultation
   Show answer and explanation

   Correct answer: D. Continue current support while requesting a structured goals-of-care meeting and, if disagreement persists, a formal ethics committee consultation

   Disputes over potentially inappropriate treatment are managed by a fair process: continued support during deliberation, expert communication about prognosis and goals, second opinions, and ethics consultation before any unilateral limitation. Covertly reducing support is deceptive and violates veracity and trust. Simply acquiescing indefinitely without discussion abandons the clinicians' obligation to prevent non-beneficial burdensome treatment, and announcing unilateral withdrawal without a due-process pathway is neither ethically nor legally defensible.

   Reference: ATS/AACN/ACCP/ESICM/SCCM Policy Statement: Responding to Requests for Potentially Inappropriate Treatments in Intensive Care Units (AJRCCM, 2015)

9. Question 9 · Cardiopulmonary Anatomy, Physiology & Pathophysiology

   A patient with severe COPD has a lung compliance of 0.10 L/cmH2O and an airway resistance of 15 cmH2O/L/sec. Approximately how long an expiratory time is needed for the lungs to empty about 95% of the tidal volume?

   1. A1.5 seconds
   2. B3.0 seconds
   3. C4.5 seconds
   4. D7.5 seconds
   Show answer and explanation

   Correct answer: C. 4.5 seconds

   One time constant equals compliance times resistance: 0.10 x 15 = 1.5 seconds, and roughly 95% of passive emptying requires three time constants, or 4.5 seconds. One time constant empties about 63% and two about 86%, so 1.5 and 3.0 seconds are insufficient; five time constants (7.5 seconds) approaches complete emptying and exceeds what the question asks.

   Reference: West's Respiratory Physiology: The Essentials, 11th ed. (Wolters Kluwer, 2021); Pilbeam's Mechanical Ventilation, 7th ed.

10. Question 10 · Oxygen Therapy, Medical Gas Delivery, Humidity & Aerosol Therapy

    A 30-year-old woman who is 20 weeks pregnant is rescued from a house fire. She is drowsy, her carboxyhemoglobin level is 22 percent, and her pulse oximeter reads 99 percent. In addition to 100 percent oxygen by non-rebreathing mask, what is the most appropriate recommendation?

    1. AObservation on room air once she becomes fully alert
    2. BImmediate exchange transfusion
    3. CIntravenous methylene blue
    4. DReferral for hyperbaric oxygen therapy
    Show answer and explanation

    Correct answer: D. Referral for hyperbaric oxygen therapy

    Hyperbaric oxygen is recommended for carbon monoxide poisoning with loss of consciousness or altered mental status, neurologic signs, severe metabolic acidosis, cardiac ischemia, or pregnancy with a carboxyhemoglobin level above roughly 15 to 20 percent, because fetal hemoglobin binds carbon monoxide avidly. Returning her to room air prolongs the elimination half-life considerably. Exchange transfusion has no established role, and methylene blue treats methemoglobinemia, not carboxyhemoglobinemia.

    Reference: Undersea and Hyperbaric Medical Society, Hyperbaric Oxygen Therapy Indications, 14th edition, and ACEP Clinical Policy on Carbon Monoxide Poisoning 2017