Where the evidence landed. The 2020 DEXA-ARDS trial showed a statistically significant reduction in 60-day mortality with a 10-day dexamethasone course (20 mg daily for 5 days then tapering) in moderate-to-severe ARDS. A 2020 individual patient data meta-analysis confirmed a mortality benefit. The current evidence favors early corticosteroid therapy in moderate-to-severe ARDS (P/F ratio below 200) when initiated within the first 14 days — not as late rescue therapy.
The methylprednisolone question. Earlier ARDS steroid trials used methylprednisolone with mixed results. The DEXA-ARDS trial used dexamethasone and showed benefit. Current 2026 clinical practice in leading ARDS centers leans toward dexamethasone at the DEXA-ARDS doses for early moderate-severe ARDS. Late initiation — after 14 days — showed harm in earlier trials and should be avoided.
What it means for RT ventilator management. Patients on steroid therapy for ARDS typically show FiO2 improvement within 3 to 5 days of initiation. RTs managing ARDS patients on dexamethasone should be looking for oxygenation improvement signals in that window and adjusting FiO2 and PEEP accordingly as the lung recovers.
What to know in practice: If your unit is not using early corticosteroids in moderate-to-severe ARDS, raise the question with your medical director and reference the DEXA-ARDS trial. If your unit is using them, track FiO2 and P/F ratio progression against steroid initiation date — the improvement timeline is clinically predictable.
The SBT is not the whole picture. Passing a spontaneous breathing trial is necessary but not sufficient for safe extubation. Approximately 20 percent of patients who pass an SBT require reintubation within 48 hours. The gap is explained by extubation failure factors the SBT does not assess: secretion management capacity, upper airway patency, laryngeal function, and swallowing safety.
The five-component framework. (1) Ventilatory mechanics — passed SBT, adequate spontaneous tidal volumes, acceptable work of breathing. (2) Oxygenation — SpO2 above 90 percent on FiO2 0.40 or less, PEEP 5 to 8 cmH2O. (3) Neurological status — follows commands, adequate cough and gag, RASS -1 to 0. (4) Secretion management — burden manageable, effective cough, frequency not exceeding every 2 hours. (5) Upper airway — cuff leak test positive, adequate subglottic space.
The cuff leak test specifically. With the cuff deflated, if air leaks around the tube with positive pressure ventilation, the subglottic space is likely adequate. No leak raises concern for post-extubation stridor — particularly in patients intubated more than 48 hours. A failed cuff leak test should prompt prophylactic dexamethasone before extubation and preparation for post-extubation HFNC or NIV.
The documentation habit that prevents reintubation: Before every extubation, document all five framework components. If any is marginal, flag it before extubation rather than noting it after reintubation. The RT who says “cuff leak is absent — recommending prophylactic dexamethasone before extubation” is practicing at the top of their scope.
Volume control (VC-AC). Delivers a set tidal volume regardless of patient effort. Guarantees the volume you set — useful when consistent volumes are the priority, such as early ARDS where you need strict 6 mL/kg IBW with precise driving pressure management. The limitation: fixed flow pattern. Patients with high respiratory drive often experience significant asynchrony with fixed-flow VC, leading to flow starvation and discomfort.
Pressure control (PC-AC). Delivers a set pressure and tidal volume varies with compliance. The decelerating flow pattern more closely matches the natural lung filling profile and is typically more comfortable for patients with active respiratory drive. Risk: if compliance changes, the tidal volume changes with it. In ARDS with rapidly changing compliance, PC can result in unintended tidal volume drift.
Pressure-regulated volume control (PRVC). A hybrid mode targeting a set tidal volume by automatically adjusting pressure limit breath to breath. Combines the guaranteed volume of VC with the decelerating flow profile of PC. Reasonable for most patients. Its limitation: in patients with highly variable compliance, automatic pressure adjustments can result in unstable delivery requiring close monitoring.
The one-sentence guide: High spontaneous drive with comfort concerns → PRVC or PC. Need for strict lung-protective volume guarantee → VC. Active spontaneous breathing with weaning in progress → pressure support. Assess work of breathing and asynchrony at the bedside rather than switching modes based on habit.
Why post-cardiac surgery respiratory management is different. Cardiopulmonary bypass produces a systemic inflammatory response that affects the lung directly. Pulmonary edema from fluid shifts during bypass, atelectasis from surgical lung collapse, phrenic nerve injury from cold cardioplegia, and pleural effusions from surgical manipulation all contribute to post-operative respiratory failure that does not follow the standard ARDS pattern.
The post-bypass lung in the first 24 hours. The most common presentation: bilateral atelectasis and mild pulmonary edema from bypass-related capillary leak. Most patients are manageable with lung-protective ventilation, early secretion mobilization, and prompt wean to extubation — the goal is extubation within 6 to 8 hours of ICU arrival in uncomplicated cases. Extended ventilation in cardiac surgery patients is associated with significantly worse outcomes.
Phrenic nerve injury and its RT implications. Phrenic nerve injury occurs in 2 to 10 percent of cardiac surgery patients from cold cardioplegia causing temporary or permanent phrenic palsy. Left hemidiaphragm elevation on CXR, failure to wean despite otherwise adequate parameters, and paradoxical abdominal movement with spontaneous breathing are the clinical signs. Diaphragm ultrasound confirms the diagnosis and is an RT-learnable skill.
If you work in a cardiac surgery ICU: Learn your unit’s early extubation protocol. Understand the standard post-bypass inhaled medications — nitric oxide and inhaled epoprostenol for pulmonary hypertension management are RT-managed. Diaphragm ultrasound is worth adding if phrenic nerve injury is a diagnostic consideration at your facility.
Next: Carbon monoxide poisoning — RT clinical assessment, management, and the hyperbaric decision.
Soon: Six-minute walk test — RT administration, interpretation, and clinical utility beyond cardiopulmonary rehab.
On deck: RT professional mentorship — how to find a mentor, how to be one, and why both matter.
Staying at the vent,
15 years across academic medical centers & community hospitals
