Objectives: Extracorporeal respiratory support, including low blood flow systems providing mainly extracorporeal CO2 removal, are increasingly applied in clinical practice. Gas exchange physiology during extracorporeal respiratory support is complex and differs between full extracorporeal membrane oxygenation and extracorporeal CO2 removal. Aim of the present article is to review pathophysiological aspects which are relevant for the understanding of hypoxemia development during extracorporeal CO2 removal. We will describe the mathematical and physiologic background underlying changes in respiratory quotient and alveolar oxygen tension during venovenous extracorporeal gas exchange and highlight the clinical implications. Design: Theoretical analysis of venovenous extracorporeal gas exchange. Setting: Italian university research hospital. Patients: None. Interventions: None. Measurements and main results: While the effect of extracorporeal CO2 removal on the respiratory quotient of the native lung has long been known, the role of extracorporeal oxygenation in dictating changes in the respiratory quotient has been less addressed. Indeed, both extracorporeal CO2 removal and extracorporeal oxygen delivery affect the respiratory quotient of the native lung and thus influence the alveolar PO2. Indeed, for the same amount of extracorporeal CO2 extraction, it is possible to reduce the FIO2, reduce the risk of absorption atelectasis, and maintain the same alveolar PO2, by increasing the extracorporeal oxygen delivery. Conclusions: Worsening of hypoxemia is frequent during low-flow extracorporeal CO2 removal combined with ultraprotective mechanical ventilation. In this context, increasing extracorporeal oxygen delivery, increases the respiratory quotient of the native lung and could reduce both the occurrence of alveolar hypoxia and absorption atelectasis, thus optimizing the residual lung function.

Cipriani, E., Langer, T., Bottino, N., Brusatori, S., Carlesso, E., Colombo, S., et al. (2020). Key Role of Respiratory Quotient to Reduce the Occurrence of Hypoxemia During Extracorporeal Gas Exchange: A Theoretical Analysis. CRITICAL CARE MEDICINE, 48(12), e1327-e1331 [10.1097/CCM.0000000000004619].

Key Role of Respiratory Quotient to Reduce the Occurrence of Hypoxemia During Extracorporeal Gas Exchange: A Theoretical Analysis

Langer, Thomas
Co-primo
;
Zanella, Alberto;Pesenti, Antonio
Penultimo
;
Grasselli, Giacomo
Ultimo
2020

Abstract

Objectives: Extracorporeal respiratory support, including low blood flow systems providing mainly extracorporeal CO2 removal, are increasingly applied in clinical practice. Gas exchange physiology during extracorporeal respiratory support is complex and differs between full extracorporeal membrane oxygenation and extracorporeal CO2 removal. Aim of the present article is to review pathophysiological aspects which are relevant for the understanding of hypoxemia development during extracorporeal CO2 removal. We will describe the mathematical and physiologic background underlying changes in respiratory quotient and alveolar oxygen tension during venovenous extracorporeal gas exchange and highlight the clinical implications. Design: Theoretical analysis of venovenous extracorporeal gas exchange. Setting: Italian university research hospital. Patients: None. Interventions: None. Measurements and main results: While the effect of extracorporeal CO2 removal on the respiratory quotient of the native lung has long been known, the role of extracorporeal oxygenation in dictating changes in the respiratory quotient has been less addressed. Indeed, both extracorporeal CO2 removal and extracorporeal oxygen delivery affect the respiratory quotient of the native lung and thus influence the alveolar PO2. Indeed, for the same amount of extracorporeal CO2 extraction, it is possible to reduce the FIO2, reduce the risk of absorption atelectasis, and maintain the same alveolar PO2, by increasing the extracorporeal oxygen delivery. Conclusions: Worsening of hypoxemia is frequent during low-flow extracorporeal CO2 removal combined with ultraprotective mechanical ventilation. In this context, increasing extracorporeal oxygen delivery, increases the respiratory quotient of the native lung and could reduce both the occurrence of alveolar hypoxia and absorption atelectasis, thus optimizing the residual lung function.
Articolo in rivista - Articolo scientifico
carbon dioxide; extracorporeal membrane oxygenation; gas exchange; hypoxemia; respiratory insufficiency
English
7-ott-2020
2020
48
12
e1327
e1331
reserved
Cipriani, E., Langer, T., Bottino, N., Brusatori, S., Carlesso, E., Colombo, S., et al. (2020). Key Role of Respiratory Quotient to Reduce the Occurrence of Hypoxemia During Extracorporeal Gas Exchange: A Theoretical Analysis. CRITICAL CARE MEDICINE, 48(12), e1327-e1331 [10.1097/CCM.0000000000004619].
File in questo prodotto:
File Dimensione Formato  
Cipriani E_ccm_2020.pdf

Solo gestori archivio

Tipologia di allegato: Publisher’s Version (Version of Record, VoR)
Dimensione 609.18 kB
Formato Adobe PDF
609.18 kB Adobe PDF   Visualizza/Apri   Richiedi una copia

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/10281/288989
Citazioni
  • Scopus 10
  • ???jsp.display-item.citation.isi??? 9
Social impact