RTLE common mistakes
RTLE · Understand the traps and how to avoid them.
Sets initial tidal volume using the patient's actual or charted body weight instead of calculating predicted body weight for lung-protective ventilation.
The 6 mL/kg figure is memorized, but the predicted-body-weight formula is skipped because the charted weight is more visible and faster to use.
What to do instead
Calculate predicted body weight from height and sex before setting tidal volume, document both actual and predicted weight, and titrate tidal volume within 4–8 mL/kg predicted body weight while monitoring plateau pressure.
Interprets an arterial blood gas as a single acid-base disorder without checking expected compensation or calculating the anion and delta gaps.
Candidates focus on the pH, PaCO2, and HCO3 values in front of them and stop at the first plausible label instead of applying a systematic compensation check.
What to do instead
Use a fixed sequence: identify the primary disorder, calculate the expected compensatory response, then calculate anion gap and delta gap to detect mixed disorders before writing the interpretation.
Chooses an air-entrainment oxygen mask at a prescribed FiO2 but sets the flow below the device's minimum, unknowingly changing the delivered oxygen concentration.
Attention goes to the percentage dial or label, while the total flow requirement and entrainment principle are overlooked.
What to do instead
Know the minimum flow for each fixed-performance device, verify delivered FiO2 with an oxygen analyzer when possible, and ensure flow meets or exceeds the patient's inspiratory demand.
Confirms endotracheal tube placement by auscultation and chest rise alone and secures the tube without continuous waveform capnography.
Auscultation is familiar and quick, and candidates may not treat capnography as the standard confirmation method in all intubated patients.
What to do instead
Use continuous waveform capnography as the primary confirmation method, document tube depth at the teeth or gums, secure the tube, and reassess placement after any movement or transfer.
Gives a bronchodilator by metered-dose inhaler without a valved holding chamber to a patient with poor hand-breath coordination, then concludes the drug is ineffective.
Device selection is treated as a formality rather than a determinant of lung deposition, so coordination and inspiratory flow are not assessed.
What to do instead
Assess hand-breath coordination and inspiratory flow before choosing a device; add a valved holding chamber or switch to a nebulizer when coordination is poor, and teach and observe technique.
Sees a rising peak airway pressure and immediately adjusts PEEP or tidal volume without performing an inspiratory hold to measure plateau pressure.
Peak pressure is displayed continuously, while plateau pressure requires an active maneuver that candidates forget under time pressure.
What to do instead
Measure plateau pressure with an inspiratory hold; if peak rises but plateau is normal, evaluate for increased resistance such as secretions or bronchospasm; if both rise, evaluate compliance and consider barotrauma or abdominal distension.
Applies adult arterial blood gas reference ranges to a neonate and labels a compensated respiratory acidosis as normal or as a pure metabolic problem.
Adult values are overlearned, and neonatal age-specific norms and expected compensation are less frequently practiced.
What to do instead
Use neonatal and age-specific blood gas norms, state the gestational and postnatal age, and evaluate compensation and oxygenation trends rather than a single value.
Documents SpO2 and respiratory rate but ignores the trend, work of breathing, and mental status when deciding whether a patient is deteriorating.
Checklist-style assessment rewards completing tasks rather than synthesizing findings, so isolated numbers are charted without interpretation.
What to do instead
Combine inspection, auscultation, trend data, and work-of-breathing indicators into a single assessment; use an early warning score and escalate when trends worsen even if individual values remain in range.
Interprets pulmonary function test numbers without verifying acceptability and reproducibility criteria or reviewing the post-bronchodilator response.
The FEV1, FVC, and ratio are treated as the answer, while quality grading and reversibility testing are treated as optional details.
What to do instead
Check effort, back-extrapolated volume, end-of-test criteria, and reproducibility before interpreting; compare pre- and post-bronchodilator values and use predicted ranges and lower limits of normal.
Explains hypoxemia that does not correct with supplemental oxygen as hypoventilation rather than distinguishing shunt from ventilation-perfusion mismatch.
The response to oxygen is not linked to the underlying mechanism, and anatomic shunt versus V/Q mismatch is not systematically compared.
What to do instead
Calculate the alveolar-arterial oxygen gradient, assess the response to supplemental oxygen, and classify the mechanism: hypoventilation corrects with oxygen, V/Q mismatch often improves, and true shunt responds poorly.