Improved oxygenation during thoractomy with selective PEEP to the dependent lung

Area of Science:

• Anesthesiology
• Thoracic Surgery
• Respiratory Physiology

Background:

• Thoracotomy in the lateral position presents challenges for maintaining adequate oxygenation.
• Conventional ventilation strategies may lead to impaired gas exchange during one-lung ventilation.

Purpose of the Study:

• To evaluate the impact of selective positive end-expiratory pressure (PEEP) applied to the dependent lung during thoracotomy.
• To compare oxygenation parameters between selective PEEP and zero end-expiratory pressure (ZEEP) ventilation of both lungs.

Main Methods:

• Twenty-two patients undergoing thoracotomy in the lateral position were studied.
• Selective PEEP was applied to the dependent lung while the non-dependent lung was ventilated with ZEEP.
• Inspired oxygen concentration and alveolar-arterial oxygen difference (AaO2D) were measured and compared to bilateral ZEEP ventilation.

Main Results:

• Selective PEEP to the dependent lung maintained adequate PaO2 with significantly lower inspired O2 concentrations (44% vs. 70%).
• The alveolar-arterial oxygen difference (AaO2D) was significantly smaller with selective PEEP (189 torr vs. 342 torr) when breathing 100% O2.
• This indicates improved gas exchange efficiency with the selective PEEP strategy.

Conclusions:

• Selective PEEP to the dependent lung is an effective strategy for improving oxygenation during thoracotomy.
• This technique allows for reduced inspired oxygen requirements and better gas exchange compared to conventional ZEEP ventilation.
• Selective PEEP may be a valuable adjunct in managing respiratory function during thoracic surgery.