吸気圧上昇時間が時間制御型適応換気で肺の排気に与える影響
Benjamin Neetz1,2,3, Patrick Rehn4,5,2, Nicole Kraus1,2
1Department of Pneumology and Critical Care Medicine, Thoraxklinik, Heidelberg University Hospital, Germany.
Respiratory care
|August 25, 2025
まとめ
吸気圧上昇時間 (IPRT) を時間制御型適応換気 (TCAV) で 0 ms に設定すると,肺の排気が改善され,運転圧 (ΔP) が低下する可能性があります. 長期IPRTは内在PEEP (PEEPi) の測定を誤導し,換気に悪影響を及ぼします.
科学分野:
- 機械的な換気
- 呼吸器の生理学
- クリティカル ケア 医療
背景:
- 呼吸道圧力放出換気 (APRV) と時間制御型適応換気 (TCAV) は,呼吸器による肺損傷 (VILI) を最小限に抑えることを目的としています.
- TCAV内のインスピレーション圧力上昇時間 (IPRT) の役割はよく理解されていません.
- 異なるIPRTは,肺の排気と主要な呼吸器のパラメータに影響を与える可能性があります.
研究 の 目的:
- TCAV中に異なるIPRTが肺の排気と呼吸器のパラメータに与える影響を調査する.
- IPRTが駆動圧 (ΔP),内在PEEP (PEEPi) および吐出潮量 (VTe) に影響するかどうかを評価する.
- TCAVで異なるIPRT下で従来のPEEPi測定の精度を評価する.
主な方法:
- TCAVで直管された10人の被験者を対象とした前向きな調査研究.
- 連続した試験でIPRTは0 ms (ベースライン),500 ms,および1,000 msであった.
- 測定には,換気器による ΔP (ΔPvent),PEEPi,VTe,弾性 (ERS),および電気阻力トモグラフィ (EIT) による終末呼吸肺容量 (EELV) が含まれていた.
主要な成果:
- 持続したIPRTは,エラスタンス誘導 ΔP (ΔPelast) を,エラスタンス誘導 ΔPventと比較して有意に増加させた.
- このΔPの上昇は,従来の測定では検出されないPEEPiの減少と関連していました.
- 電気阻力トモグラフィー (EIT) により,長時間IPRTの末期肺容量 (EELV) の減少が示されました.
結論:
- TCAV中の長期IPRTは,EELVとPEEPiを低下させ,その結果 ΔPを増加させます.
- 従来のPEEPi測定方法は,この設定では信頼できない.
- 換気を最適化し,VILIを潜在的に減らすために,TCAVプロトコルでIPRTを0msに設定することが推奨されます.
関連する概念動画
Ventilatory Modes
431
Mechanical ventilators are life-saving devices that support or replace spontaneous breathing. They deliver breaths to patients through varying methods known as ventilator modes. Understanding these modes is critical for healthcare providers managing patients with respiratory failure.
There are three ventilatory modes: full support, partial support, and spontaneous. These are described below.
Full Support Modes
Full support modes include controlled mechanical ventilation, continuous mandatory...
There are three ventilatory modes: full support, partial support, and spontaneous. These are described below.
Full Support Modes
Full support modes include controlled mechanical ventilation, continuous mandatory...
431
Pressure Relationships in Thoracic Cavity
3.1K
Breathing, otherwise known as pulmonary ventilation, is the process of air movement into and out of the lungs. The main mechanisms propelling pulmonary ventilation are atmospheric pressure (Patm), intra-pulmonary (Ppul ) or intra-alveolar pressure (Palv) within the alveoli, and intrapleural pressure (Pip) within the pleural cavity.
Breathing Mechanisms
Both intra-alveolar and intrapleural pressures rely on specific lung properties. The ability to breathe—allowing air to enter the lungs...
Breathing Mechanisms
Both intra-alveolar and intrapleural pressures rely on specific lung properties. The ability to breathe—allowing air to enter the lungs...
3.1K
Pulmonary Ventilation: Inhalation
4.7K
Pulmonary ventilation is a vital process that ensures the exchange of oxygen and carbon dioxide in the lungs. It refers to the movement of air into and out of the lungs, enabling the body to obtain oxygen and remove waste carbon dioxide. In this article, we will explore the intricacies of pulmonary ventilation, including its underlying principles, mechanisms, and the interplay of pressures within the respiratory system.
Boyle's law becomes particularly pertinent when examining respiratory...
Boyle's law becomes particularly pertinent when examining respiratory...
4.7K
Mechanical Ventilation II: Invasive Ventilation
253
Ventilators are essential medical equipment used to aid patients with respiratory difficulties. Their primary function is to assist or replace spontaneous breathing by providing mechanical ventilation. There are two general classes of mechanical ventilators: negative-pressure and positive-pressure ventilators.
Negative-Pressure Ventilators
Negative-pressure ventilators create a vacuum around the chest or body to draw air into the lungs, simulating breathing. This method does not require an...
Negative-Pressure Ventilators
Negative-pressure ventilators create a vacuum around the chest or body to draw air into the lungs, simulating breathing. This method does not require an...
253
Factors Affecting Pulmonary Ventilation
1.6K
Besides the pressure difference between the external environment and the lungs, the airflow rate and ease of pulmonary ventilation are also influenced by three other factors: surface tension of the fluid in the alveoli, compliance of the lungs, and airway resistance.
Alveolar Surface Tension
The alveolar fluid lines the luminal surface of the alveoli and exerts a force called surface tension. This force is caused by the polar water molecules in the liquid being more strongly attracted to each...
Alveolar Surface Tension
The alveolar fluid lines the luminal surface of the alveoli and exerts a force called surface tension. This force is caused by the polar water molecules in the liquid being more strongly attracted to each...
1.6K
Mechanical Ventilation I: Indication and Settings
932
Mechanical ventilation is a life-saving technique for managing acute respiratory failure and other respiratory complications. The process involves using a machine known as a ventilator to supply oxygen to the lungs and assist in removing carbon dioxide. It serves as a bridge to long-term mechanical ventilation or a temporary measure until ventilatory support is discontinued. The ventilator can maintain this function for a prolonged period, providing critical support for patients until they can...
932


