Ventilatory Management of the Surgical Critically Ill Patient

• In ICU
• Fri, 26 Sep 2025

Postoperative management of critically ill surgical patients requires tailored approaches for each type of surgery, but core principles, especially optimising mechanical ventilation, remain consistent. 

A recent article outlines essential strategies and recent advances in best practices for respiratory support in ICU postoperative care.

The IMPROVE trial demonstrated that intraoperative lung-protective ventilation, using low tidal volumes, low PEEP, and recruitment manoeuvres, significantly reduced postoperative pulmonary and extrapulmonary complications in intermediate–high-risk patients undergoing elective major abdominal surgery, compared to conventional ventilation.

Trials altering PEEP or tidal volumes alone have generally not reduced postoperative pulmonary complications. Studies like PROVILHO and PROBESE showed no benefit of high versus low PEEP (with or without recruitment manoeuvres), and an Australian trial found no difference between low and high tidal volumes at a constant PEEP. Evidence suggests the effectiveness of intraoperative ventilation depends on reducing driving pressure (plateau pressure minus PEEP), with low tidal volumes most beneficial in patients with low respiratory compliance. 

Surgical patients typically have healthier lungs than other ICU patients, and ventilation practices differ between the OR and ICU. Registry data indicate that after OR-to-ICU transfer, decreases in tidal volume often accompany increased respiratory rates, raising mechanical ventilation intensity and 28-day mortality, highlighting the need for further prospective studies.

Weaning from mechanical ventilation is a key aspect of postoperative ICU care. Patients showing inhomogeneous ventilation patterns on ICU admission, as measured by electrical impedance tomography, experienced delayed weaning, higher rates of postoperative pulmonary complications, and longer ICU stays.

Extubating patients in the OR, rather than delaying until transfer to the PACU or ICU, reduces post-extubation complications like desaturation and hypotension, despite minimally increasing OR time. Transporting intubated patients prolongs anaesthesia and ventilation and introduces additional risks, so OR extubation is preferred when feasible.

Post-extubation, prophylactic CPAP does not reduce pneumonia, reintubation, or 30-day mortality after major abdominal surgery. However, non-invasive ventilation (NIV) effectively prevents reintubation and postoperative pulmonary complications in obese surgical patients, outperforming standard oxygen therapy or high-flow nasal oxygen. Individualised high-flow oxygen as part of an open lung strategy also reduces complications after thoracic surgery with one-lung ventilation.

The PRIME-AIR bundle, including incentive spirometry and mobilisation, did not reduce postoperative pulmonary complications, though results may reflect the high standard of care in controls. Nonetheless, proper use of neuromuscular blockade management, incentive spirometry, and early mobilisation remains important. Expert guidelines recommend initiating early mobilisation within 72 hours of ICU admission for all patients, as it reduces hospital stay, postoperative complications, and ICU needs. Early mobilisation is a core component of ERAS pathways, and ICU clinicians should implement these protocols while considering surgery-specific adaptations, such as in transplant surgery.

Postoperative ICU respiratory management requires careful attention to mechanical ventilation and weaning, use of non-invasive support for patients at high risk of reintubation, strict implementation of ERAS protocols, and early mobilisation of both previously dependent and independent patients.

Source: Intensive Care Medicine
Image Credit: iStock 
 

References:

De Jong A, Jaber S, Schaefer M (2025) Key principles and recent developments for ventilatory management of the surgical critically ill patient. Intensive Care Med.