title: A novel system for organ and tissues preservation: the refrigerating hyperbaric chamber.
abstract: This study was designed to investigate the feasibility of building a simple and inexpensive device to preserve organs or tissues in hyperbaric and hypothermic conditions.
  
  
  METHODS
  The device was built on a 40-cm wide, 28-cm long, and 23-cm deep stainless steel chassis. The pressure vessel was built by a 7.8-cm bore stainless steel cylinder put inside another 12-cm cylinder welded together and closed by a steel plate on the top and bottom. The inferior plate was welded, and the superior one was fixed by manual clasp nut. The cooling system is made up of air compressor, condenser, expansion area, and cooling worm that is located between the cylinders. The temperature-controlling device is a computer processor contained in an integrated-circuit chip, with a on-off system to maintain the chamber temperature between 2 degrees to 4 degrees C. The compression of the chamber is performed by lateral coupling with the oxygen cylinder and is maintained at 5.5 absolute atmospheres and controlled by air pressure gauge. The maximal work pressure was evaluated by spreadsheet. Temperature or pressure changes were evaluated by 12- and 24-hour assays.
  
  
  RESULTS
  The maximal work pressure permitted was 6.5 absolute atmospheres. Thus, the container was free from danger. The temperature inside the chamber was kept between 2 degrees and 4 degrees C. The production costs of the prototype was US$1000.
  
  
  CONCLUSIONS
  The manufacture of the refrigerating hyperbaric chamber is viable, simple, and inexpensive.
authors.affiliation: Department of Surgery, Universidade Federal de São Paulo/Escola Paulista de Medicina (UNIFESP-EPM), Rua Botucatu 740, CEP 04023-900 São Paulo-SP, Brazil. guimarães@unisanta.br
authors.forename: F A G
authors.initials: FA
authors.lastname: Guimarães
authors.forename: M O
authors.initials: MO
authors.lastname: Taha
authors.forename: M J
authors.initials: MJ
authors.lastname: Simões
authors.forename: C A A
authors.initials: CA
authors.lastname: Moino
authors.forename: I V
authors.initials: IV
authors.lastname: Santos
authors.forename: J C
authors.initials: JC
authors.lastname: Amador
authors.forename: R A
authors.initials: RA
authors.lastname: Santos
authors.forename: R B
authors.initials: RB
authors.lastname: Queiroz
authors.forename: R R
authors.initials: RR
authors.lastname: Amaro
authors.forename: M A S
authors.initials: MA
authors.lastname: Jesus
mesh_terms: D003080:Cold Temperature; D004867:Equipment Design; D006931:Hyperbaric Oxygenation / Q000295:instrumentation / Q000379:methods*; D009926:Organ Preservation / Q000295:instrumentation / Q000379:methods*; D012034:Refrigeration; D013696:Temperature