Free NBRC CRT Exam Flashcards

Read patient data as Airway, Breathing, Circulation, Trend, then Context. The best answer follows the finding that can harm the patient soonest; a worsening trend outranks one isolated abnormal value.

Accessory muscle use, tripod positioning, and nasal flaring indicate increased work of breathing. Assess severity and support gas exchange rather than treating it as a minor or stable finding.

Suggests a tube position problem (right mainstem), pneumothorax, or a mucus plug. Check tube position, pressures, and symmetry clues rather than assuming the lung exam is simply abnormal.

When two findings conflict, trust the trend that links physiology and appearance. A patient who looks worse, speaks less, or needs more support is worsening even if one displayed value looks stable.

pH 7.35-7.45, PaCO2 35-45 mmHg, HCO3- 22-26 mEq/L, PaO2 80-100 mmHg on room air, SaO2 95-100%, base excess -2 to +2 mEq/L. Interpret acid-base, ventilation, and oxygenation as separate questions.

1) Classify pH (acidemic/alkalemic/normal). 2) Check PaCO2 (respiratory component). 3) Check HCO3- (metabolic component). 4) Decide if compensation is present. 5) Interpret oxygenation. Name the primary disturbance first.

Low pH with high PaCO2 (>45 mmHg) from hypoventilation (COPD, sedation, neuromuscular weakness). Acute uncompensated example: pH 7.25, PaCO2 62, HCO3- 26. CO2 retention lowers pH—support ventilation.

Compensation moves pH back toward normal but not past it. If pH is still acidemic, the primary problem is an acidosis even after the compensating value shifts. If PaCO2 and HCO3- move so pH worsens, suspect a mixed disorder.

PaO2 divided by FiO2 expressed as a decimal (e.g., FiO2 0.50). It exposes oxygenation impairment hidden by high oxygen settings—a normal PaO2 on high FiO2 can still represent severe gas-exchange failure.

An acceptable SpO2 does not guarantee adequate oxygen delivery when hemoglobin is low or abnormal hemoglobins are present. Low hemoglobin reduces oxygen content and can explain dyspnea despite a reassuring saturation.

Start with FEV1/FVC for obstruction, TLC for restriction, bronchodilator response for reversibility, and DLCO for diffusion. A reduced FEV1/FVC ratio points to an obstructive pattern.

Low hemoglobin lowers oxygen content; elevated WBC with neutrophils supports a bacterial pattern; elevated BNP supports heart-failure edema; elevated lactate raises shock/sepsis concern. Use labs as support, not isolated answers.

Hyperkalemia: tall peaked T waves and widening QRS (urgent conduction/arrest risk). Hypokalemia: flattened T waves and ST depression with weakness and dysrhythmia risk that can worsen ventilation.

Right axis deviation, a tall R wave in V1, or peaked P waves support chronic lung disease, pulmonary hypertension, or cor pulmonale. ST changes with dyspnea may point to cardiac ischemia instead of a primary lung problem.

Verify (sample/probe/device), Stabilize (treat ABC threats), Classify (the dominant problem), Match (the targeted action), Reassess (response data). The recommendation should solve the verified problem, not decorate it.

More oxygen corrects hypoxemia but not CO2 retention. Drowsiness, acidemia, and rising PaCO2 call for ventilatory support, not just a higher FiO2—matching the action to the cause is the tested skill.

When a measurement conflicts with the patient, device setup, or sampling method, check sample quality, probe placement, oxygen source, and patient identity before changing therapy on a possibly artifactual value.

Low-flow systems (nasal cannula, simple mask, non-rebreather) deliver variable FiO2 that changes with breathing pattern. Fixed-performance systems (Venturi mask, blender, HFNC) deliver a more controlled FiO2.

A simple mask must run at least 5 L/min to flush exhaled CO2 from the mask and prevent rebreathing. Too little flow allows CO2 accumulation—an exam trap when flow is set too low.

The exam choice when a precise, fixed FiO2 matters—especially in COPD with CO2-retention risk needing controlled titration. Blocked entrainment ports change the delivered FiO2.

Delivers high FiO2 for severe hypoxemia while definitive care is prepared. A collapsed reservoir bag means troubleshoot flow and valves first—keep the bag inflated with high flow.

CPAP recruits alveoli in an alert patient with cardiogenic pulmonary edema. BiPAP (bilevel) adds inspiratory support for hypercapnia with spontaneous breathing—both require an intact, protectable airway and cooperation.

Used for aerosolized humidity, often via trach collar. Watch FiO2 accuracy and adequate total flow; a weak mist or heavy rainout signals a device or flow problem to troubleshoot.

Appropriate for short-term ventilation with stable secretions. It adds dead space and resistance and can become wet or plugged—rising pressure or thick secretions means switch to active heated humidification.

An endotracheal or tracheostomy tube bypasses the upper airway's warming and humidifying function. Dry gas thickens secretions, increases airway resistance, injures mucosa, and risks tube obstruction.

A spacer reduces the timing/coordination demand of a metered-dose inhaler and decreases oropharyngeal deposition. It is the device fix for poor hand-breath coordination—one actuation at a time.

A short-acting beta agonist works if peak flow improves, wheeze and accessory use decrease, and the patient speaks more easily. Tachycardia and tremor are adverse effects, NOT proof of therapeutic success.

Ipratropium is an anticholinergic bronchodilator often paired with a beta agonist in COPD exacerbations. Avoid spraying it in the eyes—it can cause irritation and worsen narrow-angle glaucoma symptoms.

Used for upper-airway edema with stridor (e.g., post-extubation, croup). Monitor for rebound symptoms after the effect wears off and watch heart rate during and after delivery.

A helium-oxygen mix can reduce work of breathing in upper-airway obstruction or severe airflow limitation, but only when the patient's oxygen requirement is low enough to allow a helium-rich mixture.

An oral airway is for an unconscious patient WITHOUT a gag reflex. A nasal airway is better tolerated when a gag reflex is present—avoid the nasal route with suspected basilar skull fracture or severe midface trauma.

Confirm with symmetric chest rise, bilateral breath sounds, absent gastric sounds, exhaled CO2 detection, improving oxygenation, and chest radiograph. Exhaled CO2 is especially important immediately after placement.

A common adult ET tube tip target is about 2-6 cm above the carina on chest radiograph. Absent left-sided breath sounds with louder right-sided sounds suggests right mainstem placement—withdraw slightly per protocol.

Adult endotracheal or tracheostomy cuff pressure is commonly maintained around 20-30 cmH2O to limit air leak while reducing tracheal mucosal injury from excessive pressure.

Suction based on clinical need (not a fixed schedule), use an appropriate catheter size, and stop if severe hypoxemia, bradycardia, or distress develops. Reoxygenate and reassess before resuming.

Never silence an alarm as the primary action. Assess the patient first; if deteriorating, disconnect and manually ventilate with 100% oxygen while the airway, circuit, gas source, and ventilator are checked.

Increased resistance or decreased compliance: secretions, bronchospasm, biting, coughing, water in tubing, kinks, or pneumothorax. First move: assess patient, airway, and tubing and evaluate the need for suctioning.

Gas is escaping or not delivered: circuit disconnection, loose connection, circuit or cuff leak, low supply pressure, or exhalation-valve issue. First move: reconnect and inspect from airway to machine.

High peak pressure with a normal plateau suggests an airway-resistance problem (secretions, bronchospasm, kink). High peak AND high plateau suggests decreased compliance or overdistention.

Volume control sets tidal volume and minute ventilation directly (pressure varies). Pressure control sets inspiratory pressure (tidal volume varies). Choose the mode by the problem you must guarantee.

Oxygenation is managed mainly with FiO2 and PEEP (mean airway pressure). Ventilation (CO2) is managed mainly with minute ventilation—rate and tidal volume changes. Match the setting to the problem.

Favor low tidal volume around 6 mL/kg ideal body weight and plateau pressure at or below 30 cmH2O. Permissive hypercapnia may be acceptable when pH is tolerable and oxygenation is managed safely.

Tidal volume is based on ideal body weight, not actual weight—commonly 6-8 mL/kg, with ~6 mL/kg when ARDS or poor compliance is present. PEEP often starts near 5 cmH2O unless oxygenation requires more.

The original problem improving, stable oxygenation on modest FiO2/PEEP, hemodynamic stability, adequate mental status and airway protection, manageable secretions, and enough strength to breathe spontaneously.

Respiratory rate divided by tidal volume in liters. A value below approximately 105 is a favorable weaning sign, but it must be interpreted with the full clinical picture, not used alone.

Rising respiratory rate (e.g., above ~35/min with distress), falling SpO2, rising PaCO2, tachycardia, hypertension, diaphoresis, anxiety, or accessory use. Return the patient to support and evaluate the cause.

For acute deterioration on a ventilator: Displacement of the tube, Obstruction (secretions/kink/biting), Pneumothorax, Equipment failure. Run DOPE with ABC before fine-tuning routine settings.

A full oxygen E cylinder is about 2200 psig. Duration problems use usable cylinder pressure times the cylinder factor divided by the flow rate—replace before pressure is unsafe for transport.

Secure storage upright and chained, no oil or grease near oxygen fittings, correct regulator assembly, leak checks, and timely replacement before pressure becomes unsafe for transport.

C. difficile requires soap-and-water hand hygiene after care because alcohol-based hand rub does not reliably remove spores. Use gown and gloves and treat as an enteric contact precaution.