title: Cardiorespiratory impact of transesophageal endoscopic mediastinoscopy compared with cervical mediastinoscopy: a randomized experimental study.
abstract: BACKGROUND
  Transesophageal natural-orifice transluminal endoscopic surgery (NOTES) mediastinoscopy has been described as a feasible, less-invasive alternative to video-assisted mediastinoscopy (VAM). We aimed to investigate hemodynamic and respiratory effects during transesophageal NOTES mediastinoscopy compared with VAM.
  
  
  METHODS
  This was a short-survival experiment in 20 female pigs randomized to NOTES (n = 10) or VAM (n = 10) mediastinoscopy. In the NOTES group, an endoscopist accessed the mediastinum through a 5-cm submucosal tunnel in the esophageal wall, and CO2 was used to create the pneumomediastinum. Conventional VAM was carried out by thoracic surgeons. A 30-minute systematic exploration of the mediastinum was then performed, including invasive monitoring for hemodynamic and respiratory data. Blood samples were drawn for gas analyses.
  
  
  RESULTS
  All experiments except 2 in the NOTES group (one because of technical difficulties, the other because of thoracic lymphatic duct lesion) were completed as planned, and animals survived 24 hours. Also, 3 animals in the NOTES group presented a tension pneumothorax that was immediately recognized and percutaneously drained. VAM and NOTES animals showed similar pulmonary and systemic hemodynamic behavior during mediastinoscopy. Pulmonary gas exchange pattern was mildly impaired during the NOTES procedure, showing lower partial arterial oxygen pressure associated with higher airway pressures (more important in animals that presented with pneumothorax).
  
  
  CONCLUSIONS
  NOTES mediastinoscopy induces minimal deleterious respiratory effects and hemodynamic changes similar to conventional cervical VAM and could be feasible when performed under strict hemodynamic and respiratory surveillance. Notably, serious complications caused by the injury of pleura are more frequent in NOTES, which mandates an improvement in technique and suitable equipment.
authors.affiliation: Hospital Clínic Barcelona, University of Barcelona, Spain.
authors.forename: Ricard
authors.initials: R
authors.lastname: Navarro-Ripoll
authors.affiliation: Hospital Clínic Barcelona, University of Barcelona, Spain.
authors.forename: Henry
authors.initials: H
authors.lastname: Córdova
authors.affiliation: Hospital Clínic Barcelona, University of Barcelona, Spain.
authors.forename: Antonio
authors.initials: A
authors.lastname: Rodríguez-D'Jesús
authors.affiliation: Hospital Clínic Barcelona, University of Barcelona, Spain.
authors.forename: Marc
authors.initials: M
authors.lastname: Boada
authors.affiliation: Hospital Clínic Barcelona, University of Barcelona, Spain.
authors.forename: Cristina
authors.initials: C
authors.lastname: Rodríguez de Miguel
authors.affiliation: Hospital Clínic Barcelona, University of Barcelona, Spain.
authors.forename: Mireia
authors.initials: M
authors.lastname: Beltrán
authors.affiliation: Hospital Clínic Barcelona, University of Barcelona, Spain.
authors.forename: Georgina
authors.initials: G
authors.lastname: Cubas
authors.affiliation: Hospital Clínic Barcelona, University of Barcelona, Spain.
authors.forename: Juan
authors.initials: J
authors.lastname: Perdomo
authors.affiliation: Hospital Clínic Barcelona, University of Barcelona, Spain Instituto de Investigaciones Biomédicas August Pi i Sunyer (IDIBAPS), Barcelona, Spain Centro de Investigación Biomédica en Red en el Área temática de Enfermedades Hepáticas y Digestivas (CIBEREHD), Barcelona, Spain.
authors.forename: Josep
authors.initials: J
authors.lastname: Llach
authors.affiliation: Hospital Clínic Barcelona, University of Barcelona, Spain.
authors.forename: Jaume
authors.initials: J
authors.lastname: Balust
authors.affiliation: Hospital Clínic Barcelona, University of Barcelona, Spain.
authors.forename: Josep M
authors.initials: JM
authors.lastname: Gimferrer
authors.affiliation: Hospital Clínic Barcelona, University of Barcelona, Spain Instituto de Investigaciones Biomédicas August Pi i Sunyer (IDIBAPS), Barcelona, Spain Centro de Investigación Biomédica en Red en el Área temática de Enfermedades Hepáticas y Digestivas (CIBEREHD), Barcelona, Spain mgfernan@clinic.ub.es.
authors.forename: Gloria
authors.initials: G
authors.lastname: Fernández-Esparrach
authors.affiliation: Hospital Clínic Barcelona, University of Barcelona, Spain Instituto de Investigaciones Biomédicas August Pi i Sunyer (IDIBAPS), Barcelona, Spain.
authors.forename: Graciela
authors.initials: G
authors.lastname: Martínez-Pallí
mesh_terms: D000818:Animals; D005260:Female; D006439:Hemodynamics / Q000502:physiology; D008481:Mediastinoscopy / Q000009:adverse effects / Q000379:methods; D057605:Natural Orifice Endoscopic Surgery / Q000009:adverse effects* / Q000379:methods; D010313:Partial Pressure; D011659:Pulmonary Gas Exchange / Q000502:physiology; D011897:Random Allocation; D013552:Swine
keywords: NOTES; flexible endoscopy; interventional endoscopy