title: Comparative changes in tissue oxygenation between laparoscopic and open cholecystectomy.
abstract: BACKGROUND
  Previous studies examined the effect of laparoscopic cholecystectomy (LC) versus open cholecystectomy (OC) on physiological variables of the respiratory system. In this study we compared changes in arterial blood gases-related parameters between LC and OC to assess their comparative influence on gas exchange.
  
  
  METHODS
  We studied 28 patients, operated under identical anesthetic protocol (LC: 18 patients, OC: 10 patients). Measurements were made on the morning before surgery (BS), the second (AS2) and the eighth (AS8) postoperative day. Studied parameters, including alveolar-arterial difference in PO2 ((A-a)DO2) and oxygen content (Oct in vol%), were statistically compared.
  
  
  RESULTS
  On AS2 a greater increase was found in ((A-a)DO2) for the OC compared to LC (4.673 ± 0.966 kPa versus 3.773 ± 1.357 kPa, respectively). Between BS and AS2, Oct in vol% decreased from 17.55 ± 1.90 to 15.69 ± 1.88 in the LC and from 16.99 ± 2.37 to 14.62 ± 2.23 in the OC, whilst a reduction (P = 0.093) between AS2 and AS8 was also found for the open method. Besides, on AS2, SaO2% decrease was greater in OC compared to LC (P = 0.096).
  
  
  CONCLUSIONS
  On AS2, the greater increase in OC-((A-a)DO2) associated with Oct in vol% and SaO2% findings also in OC group suggest that LC might be associated with lower risk for impaired tissue oxygenation.
authors.affiliation: Department of Experimental Physiology, Medical School, Democritous University of Thrace, 68100 Dragana, Alexandroupolis, Greece ; Technological Educational Institute (T.E.I.) of Athens, Agiou Spyridonos 28 Street, 12243 Egaleo, Athens, Greece.
authors.forename: George D
authors.initials: GD
authors.lastname: Bablekos
authors.affiliation: "Sismanogleio" General Hospital, First Thoracic Medicine Department, Sismanogleiou 1 Street, 15126 Maroussi, Athens, Greece.
authors.forename: Stylianos A
authors.initials: SA
authors.lastname: Michaelides
authors.affiliation: Department of Hygiene, Epidemiology and Medical Statistics, Medical School, National and Kapodistrian University of Athens, Mikras Asias 75 Street, 11527 Goudi, Athens, Greece.
authors.forename: Antonis
authors.initials: A
authors.lastname: Analitis
authors.affiliation: Department of Experimental Physiology, Medical School, National and Kapodistrian University of Athens, Mikras Asias 75 Street, 11527 Goudi, Athens, Greece.
authors.forename: Maria H
authors.initials: MH
authors.lastname: Lymperi
authors.affiliation: Department of Experimental Physiology, Medical School, Democritous University of Thrace, 68100 Dragana, Alexandroupolis, Greece.
authors.forename: Konstantinos A
authors.initials: KA
authors.lastname: Charalabopoulos
keywords: Arterial oxygenation; Cholecystectomy; Laparoscopic; Open