title: The consumption of glucose during ex vivo lung perfusion correlates with lung edema.
abstract: BACKGROUND
  Ex vivo lung perfusion (EVLP) has been recently proposed to recondition organs before transplantation from donors with marginal or unacceptable features. The aim of our investigation was to explore glucose consumption during EVLP.
  
  
  METHODS
  We investigated 8 domestic pigs (mean weight, 21 ± 0.8 kg). After perfusion with Perfadex, retrieval, and back table surgery, we initiated EVLP. The lungs were perfused with Steen solution with added methylprednisolone, cefazoline, and heparin. The blood flow was gradually increased with a target of 40% of the estimated cardiac output (or less if the pulmonary artery pressure was >15 mm Hg), while keeping the left atrial pressure between 3 and 5 mm Hg. The temperature of the perfusate was increased from 25 °C to 37 °C. Once the temperature of the lung outflow was >32 °C, we began gas flow (4 L/min, 5%-8% CO(2) in air) and mechanical ventilation. EVLP parameters and blood gases were measured throughout the experiment; glucose consumption was calculated as (glucose initial-glucose final)/time. The wet to dry ratio was also calculated as an index of lung edema.
  
  
  RESULTS
  When stratified by median glucose consumption (0.237 mg/min), high glucose consumers (0.588 ± 0.17) were characterized by worse lung function, as assessed by oxygenation (partial pressure of oxygen/inspiratory fraction of oxygen [PaO(2)/FiO(2)] 326 ± 63 mm Hg vs 218 ± 84; P=.083 low vs high, respectively), and lung edema (wet/dry ratio 6.5 ± 0.7 vs 8.6 ± 0.9; P=.012). Glucose consumption correlated with wet to dry ratio (R(2)=0.663; P=.014).
  
  
  CONCLUSIONS
  We found that the worse the lung function, the greater the consumption of glucose during EVLP. This observation suggests the need to explore lung metabolism during EVLP to possibly obtain metrics for evaluation.
authors.affiliation: Dipartimento di Anestesia, Terapia Intensiva e Subintensiva e Terapia del Dolore, Fondazione IRCCS Cà Granda-Ospedale Maggiore Policlinico, Milan, Italy. franco.valenza@unimi.it
authors.forename: F
authors.initials: F
authors.lastname: Valenza
authors.forename: L
authors.initials: L
authors.lastname: Rosso
authors.forename: M
authors.initials: M
authors.lastname: Pizzocri
authors.forename: V
authors.initials: V
authors.lastname: Salice
authors.forename: M
authors.initials: M
authors.lastname: Umbrello
authors.forename: G
authors.initials: G
authors.lastname: Conte
authors.forename: A
authors.initials: A
authors.lastname: Stanzi
authors.forename: J
authors.initials: J
authors.lastname: Colombo
authors.forename: S
authors.initials: S
authors.lastname: Gatti
authors.forename: L
authors.initials: L
authors.lastname: Santambrogio
authors.forename: G
authors.initials: G
authors.lastname: Iapichino
authors.forename: L
authors.initials: L
authors.lastname: Gattinoni
mesh_terms: D000818:Animals; D002437:Cefazolin / Q000008:administration & dosage; D002951:Citrates / Q000008:administration & dosage; D004734:Energy Metabolism; D005947:Glucose / Q000008:administration & dosage / Q000378:metabolism*; D006439:Hemodynamics; D006493:Heparin / Q000008:administration & dosage; D016014:Linear Models; D008168:Lung / Q000098:blood supply / Q000378:metabolism / Q000601:surgery*; D016040:Lung Transplantation / Q000009:adverse effects*; D008775:Methylprednisolone / Q000008:administration & dosage; D023421:Models, Animal; D019188:Organ Preservation Solutions / Q000008:administration & dosage / Q000378:metabolism*; D010477:Perfusion / Q000009:adverse effects*; D011654:Pulmonary Edema / Q000209:etiology / Q000378:metabolism* / Q000503:physiopathology; D012121:Respiration, Artificial; D034421:Sus scrofa; D013696:Temperature; D013997:Time Factors
chemical_list: D002951:Citrates; D019188:Organ Preservation Solutions; C070005:Perfadex; D006493:Heparin; D002437:Cefazolin; D005947:Glucose; D008775:Methylprednisolone