What are the complications of prolonged mechanical ventilation (MV) beyond 24 hours post-operatively?

From the Guidelines

Prolonged mechanical ventilation beyond 24 hours when not medically necessary can lead to significant complications, including ventilator-associated pneumonia, barotrauma, volutrauma, atelectrauma, and oxygen toxicity, as well as physical complications such as tracheal injury, vocal cord damage, and diaphragmatic weakness. These complications can be minimized by early extubation, when medically appropriate, and daily assessment of readiness for extubation, spontaneous breathing trials, and protocols for ventilator weaning 1.

Key Complications

• Ventilator-associated pneumonia, which can develop within 48-72 hours
• Barotrauma (lung injury from pressure)
• Volutrauma (injury from excessive volume)
• Atelectrauma (repeated opening and closing of alveoli)
• Oxygen toxicity from high FiO2 levels
• Physical complications include tracheal injury from the endotracheal tube, leading to stenosis or tracheomalacia; vocal cord damage; and diaphragmatic weakness that begins within 18-24 hours of mechanical ventilation
• Patients may also experience deconditioning, muscle weakness, and ICU-acquired weakness
• Sedation required for ventilation can lead to delirium, cognitive impairment, and prolonged ICU stays

Recommendations

• Daily assessment of readiness for extubation, spontaneous breathing trials, and protocols for ventilator weaning can help reduce unnecessary ventilation time 1
• Managing patients with a ventilator liberation protocol can reduce the time spent on mechanical ventilation 1
• For patients at high risk for extubation failure who have been receiving mechanical ventilation for more than 24 h, and who have passed an SBT, extubation to preventative NIV is recommended 1

From the Research

Complications of Prolonged Ventilator Use

• Prolonged use of mechanical ventilation can lead to various complications, including airway-associated complications, complications in the response of patients to mechanical ventilation, and complications related to the patient's response to the device for mechanical ventilation 2.
• Mechanical ventilation can worsen or cause acute lung injury, increase alveolar/capillary permeability by overdistension of the lungs (volutrauma), exacerbate lung damage due to the recruitment/derecruitment of collapsed alveoli (atelectrauma), and cause subtle damages due to the activation of inflammatory processes (biotrauma) 2, 3.
• Spontaneous breathing during mechanical ventilation can improve oxygenation, but it may also cause or worsen acute lung injury, especially if acute respiratory distress syndrome is severe and spontaneous effort is vigorous 4.
• The use of partial support modes of ventilation, which allow for spontaneous breathing, is increasing, but it is essential to weigh the benefits and risks of spontaneous breathing during mechanical ventilation 4.
• Prolonged sedation and mechanical ventilation can lead to disuse and loss of peripheral muscle and diaphragm function, making it challenging to wean patients from the ventilator 5.
• Weaning from mechanical ventilation is a critical step, and protocols should be used together with daily clinical evaluation of the patient to overcome problems due to an exclusively clinical opinion 5.

Risks of Unnecessary Prolonged Ventilator Use

• Unnecessary prolonged use of mechanical ventilation can increase the risk of complications, such as airway-associated complications, lung injury, and muscle weakness 2, 3.
• Prolonged mechanical ventilation can also lead to increased length of stay in the intensive care unit, increased costs of care, and increased morbidity and mortality 6, 5.
• It is crucial to identify the correct timing of therapeutic steps for weaning and subsequent extubation to minimize the risks associated with prolonged mechanical ventilation 5.