From the Guidelines
Paralyzing a patient with Acute Respiratory Distress Syndrome (ARDS) can help with management by decreasing mortality and reducing the incidence of barotrauma, as evidenced by a pooled analysis of seven RCTs that included 1,598 patients, which demonstrated a reduced mortality rate with the use of neuromuscular blocking agents (NMBAs) compared to those who did not receive NMBAs (RR, 0.74; 95% CI, 0.56-0.98) 1.
Key Points to Consider
- The use of NMBAs, such as cisatracurium, can improve oxygenation and outcomes in patients with moderate-to-severe ARDS by enhancing ventilator synchrony and reducing oxygen consumption.
- NMBAs prevent patient-ventilator dyssynchrony, which can cause volutrauma and barotrauma to the lungs, and allow for precise control of tidal volumes and plateau pressures, facilitating lung-protective ventilation strategies.
- The mechanism of benefit of NMBAs is unclear, but likely involves decreasing ventilator-induced lung injury via a reduction in patient-ventilator dyssynchrony, in addition to reducing oxygen consumption, inflammation, and alveolar fluid 1.
- Patients receiving NMBAs must be adequately sedated to prevent awareness during paralysis, and regular assessment for paralysis depth using train-of-four monitoring is essential.
- The use of NMBAs should be reserved for patients with the most severe ARDS, mainly in the acute phase and during the first 48 hours of mechanical ventilation, and should be discontinued as soon as possible to minimize complications like critical illness myopathy 1.
Important Considerations
- The incidence of ICU-acquired weakness is probably increased with the use of NMBAs, and patients should receive DVT prophylaxis and proper positioning to prevent pressure injuries during immobilization.
- Sedation should be reduced and partial ventilator support can be used to promote respiratory muscle activity whenever gas exchange, respiratory mechanics, and hemodynamic status have improved.
- The benefits of NMBAs in reducing mortality and barotrauma should be weighed against the potential risks, and the decision to use NMBAs should be made on a case-by-case basis, taking into account the individual patient's condition and response to treatment.
From the Research
Benefits of Paralyzing a Patient with ARDS
- Paralyzing a patient with Acute Respiratory Distress Syndrome (ARDS) using neuromuscular blocking agents (NMBAs) has been shown to improve oxygenation and decrease ventilator-induced lung injury 2, 3, 4.
- The use of NMBAs in ARDS patients has been associated with lower adjusted 90-day mortality, decreased morbidity, and increased ventilator-free days 2, 4.
- A systematic review of three original randomized controlled trials investigating the use of NMBAs in severe ARDS found that two of the three trials demonstrated improved primary outcomes with the use of NMBA 3.
Mechanism of Action
- NMBAs induce reversible muscle paralysis, which can help facilitate mechanical ventilation and improve oxygenation in ARDS patients 5.
- The use of NMBAs can also help reduce ventilator-induced lung injury by decreasing the risk of barotrauma and volutrauma 2, 4.
Clinical Outcomes
- Studies have shown that the use of NMBAs in ARDS patients can improve clinical outcomes, including:
- However, one study found that the use of continuous infusion neuromuscular blockade with cisatracurium in patients with severe ARDS on venovenous extracorporeal membrane oxygenation (ECMO) did not improve clinical outcomes compared to no neuromuscular blockade 6.