Grassi Alice, Teggia-Droghi Maddalena, Borgo Asia, Szudrinsky Konstanty, Bellani Giacomo
Department of Anesthesiology and Pain Medicine, University of Toronto, Toronto General Hospital, University Health Network, Toronto, ON, Canada.
Department of Emergency and Intensive Care, San Gerardo Hospital, Monza, Italy.
Crit Care Explor. 2024 Jan 16;6(1):e1031. doi: 10.1097/CCE.0000000000001031. eCollection 2024 Jan.
To assess the feasibility of setting the tidal volume (TV) as 25% of the actual aerated lung volume (rather than on ideal body weight) in patients with Acute Respiratory Distress Syndrome (ARDS).
Physiologic prospective single-center pilot study.
Medical ICU specialized in the care of patients with ARDS.
Patients with moderate-severe ARDS deeply sedated or paralyzed, undergoing controlled mechanical ventilation with a ventilator able to measure the end-expiratory lung volume (EELV) with a washin, washout technique.
Three-phase study (baseline, strain-selected TV setting, ventilation with strain-selected TV for 24 hr). The TV was calculated as 25% of the measured EELV minus the static strain due to the applied positive end-expiratory pressure.
Gas exchanges and respiratory mechanics were measured and compared in each phase. In addition, during the TV setting phase, driving pressure (DP) and lung strain (TV/EELV) were measured at different TVs to assess the correlation between the two measurements. The maintenance of the set strain-selected TV for 24 hours was safe and feasible in 76% of the patients enrolled. Three patients dropped out from the study because of the need to set a respiratory rate higher than 35 breaths per minute to avoid respiratory acidosis. The DP of the respiratory system was a satisfactory surrogate for strain in this population.
In our population of 17 patients with moderate to severe ARDS, setting TV based on the actual lung size was feasible. DP was a reliable surrogate of strain in these patients, and DP less than or equal to 8 cm HO corresponded to a strain less than 0.25.
评估在急性呼吸窘迫综合征（ARDS）患者中将潮气量（TV）设定为实际通气肺容积的25%（而非理想体重）的可行性。
生理学前瞻性单中心试点研究。
专门护理ARDS患者的医学重症监护病房。
中重度ARDS患者，深度镇静或麻痹，使用能够通过冲洗、洗脱技术测量呼气末肺容积（EELV）的呼吸机进行控制性机械通气。
分为三个阶段的研究（基线、根据应变选择潮气量设置、使用根据应变选择的潮气量通气24小时）。潮气量计算为测量的EELV的25%减去因呼气末正压应用导致的静态应变。
在每个阶段测量并比较气体交换和呼吸力学。此外，在潮气量设置阶段，在不同潮气量下测量驱动压（DP）和肺应变（TV/EELV），以评估这两项测量之间的相关性。在76%的入组患者中，维持根据应变选择的潮气量设置24小时是安全可行的。三名患者因需要将呼吸频率设定高于35次/分钟以避免呼吸性酸中毒而退出研究。在该人群中，呼吸系统的DP是应变的一个满意替代指标。
在我们的17例中重度ARDS患者群体中，根据实际肺大小设置潮气量是可行的。DP是这些患者应变的可靠替代指标，DP小于或等于8 cm H₂O对应应变小于0.25。
