Lung Protection Ventilation During General Anesthesia

Over the past two decades it has become well-established that general anesthesia can impair the respiratory system. Muscle paralysis, airway management, mechanical ventilation, patient position and surgery are contributing factors – individually or in combination – and may lead to complications. We will shed some light on various aspects of lung protective ventilation in the OR.

More than 230 million surgical procedures are undertaken each year worldwide¹. Many of these patients receive general anesthesia with its attendant mechanical ventilation, which exposes them to the potential risk of postoperative pulmonary complications. Although results from research conducted on this topic are inconclusive, evidence gained over the past few years suggests that lung protection strategies be used for surgical patients despite the fact that not all questions have been sufficiently answered.

This article explores the current discussion on intraoperative lung protective ventilation strategies. The literature reviewed focuses the discussion on the following ventilator settings and parameters: tidal volume (VT), use of positive end-expiratory pressure (PEEP) and applied oxygen fraction (FiO₂) as well as recruitment maneuvers and plateau/driving pressures. Many studies discuss the effects of tidal volume ranges on the lungs during intraoperative ventilation. These trials have suggested that lung protective strategies encompassing reduced VT have a positive effect on the incidence of PPCs². This is, however, not a standard of care in the operating theater at present. On the other hand, the use and benefit of PEEP still appear to be controversial. Now an optimal PEEP remains to be defined; the discussion currently tends toward moderate to low PEEP³. In addition, titrated approaches are being suggested in order to adapt PEEP and recruitment maneuvers to the individual patient. Regarding FiO₂, it was assumed in the past that a high inspired oxygen fraction would improve oxygenation and reduce postoperative nausea and vomiting (PONV) as well as prevent surgical site infections: Today, this perception seems to have changed¹.

Protective ventilation in the OR creates significant demands on the anesthesia workstation. In the following, further materials / contents will be made available, which can help to assess the topic or provide added value.