Lung volumes, respiratory mechanics and dynamic strain during general anaesthesia

Valter Perilli, Liliana Sollazzi, Massimo Antonelli, Benedetta Romano, Pierpaolo Ciocchetti, Davide Eleuteri, Antonio Maria Dell'Anna, Filippo Bongiovanni

Risultato della ricerca: Contributo in rivistaArticolo in rivista

12 Citazioni (Scopus)

Abstract

Background: Driving pressure (ΔP) represents tidal volume normalised to respiratory system compliance (CRS) and is a novel parameter to target ventilator settings. We conducted a study to determine whether CRS and ΔP reflect aerated lung volume and dynamic strain during general anaesthesia. Methods: Twenty non-obese patients undergoing open abdominal surgery received three PEEP levels (2, 7, or 12 cm H2O) in random order with constant tidal volume ventilation. Respiratory mechanics, lung volumes, and alveolar recruitment were measured to assess end-expiratory aerated volume, which was compared with the patient's individual predicted functional residual capacity in supine position (FRCp). Results: CRS was linearly related to aerated volume and ΔP to dynamic strain at PEEP of 2 cm H2O (intraoperative FRC) (r=0.72 and r=0.73, both P<0.001). These relationships were maintained with higher PEEP only when aerated volume did not overcome FRCp (r=0.73, P<0.001; r=0.54, P=0.004), with 100 ml lung volume increases accompanied by 1.8 ml cm H2O−1 (95% confidence interval [1.1–2.5]) increases in CRS. When aerated volume was greater or equal to FRCp (35% of patients at PEEP 2 cm H2O, 55% at PEEP 7 cm H2O, and 75% at PEEP 12 cm H2O), CRS and ΔP were independent from aerated volume and dynamic strain, with CRS weakly but significantly inversely related to alveolar dead space fraction (r=–0.47, P=0.001). PEEP-induced alveolar recruitment yielded higher CRS and reduced ΔP only at aerated volumes below FRCp (P=0.015 and 0.008, respectively). Conclusions: During general anaesthesia, respiratory system compliance and driving pressure reflect aerated lung volume and dynamic strain, respectively, only if aerated volume does not exceed functional residual capacity in supine position, which is a frequent event when PEEP is used in this setting.
Lingua originaleEnglish
pagine (da-a)1156-1165
Numero di pagine10
RivistaBritish Journal of Anaesthesia
Volume121
DOI
Stato di pubblicazionePubblicato - 2018

Keywords

  • Abdomen
  • Aged
  • Anesthesia, General
  • Female
  • Functional Residual Capacity
  • Humans
  • Lung Compliance
  • Lung Volume Measurements
  • Male
  • Middle Aged
  • Peak Expiratory Flow Rate
  • Positive-Pressure Respiration
  • Pulmonary Alveoli
  • Respiratory Mechanics
  • Respiratory Muscles
  • Supine Position
  • Tidal Volume
  • functional residual capacity
  • positive end-expiratory pressure
  • respiratory mechanics

Fingerprint

Entra nei temi di ricerca di 'Lung volumes, respiratory mechanics and dynamic strain during general anaesthesia'. Insieme formano una fingerprint unica.

Cita questo