Comparison of volume-controlled and pressure-controlled ventilation using a laryngeal mask airway during gynecological laparoscopy

Background: Several publications have reported the successful, safe use of Laryngeal Mask Airway (LMA)-Classic devices in patients undergoing laparoscopic surgery. However, there have been no studies that have examined the application of volume-controlled ventilation (VCV) or pressure-controlled ventilation (PCV) using a LMA during gynecological laparoscopy. The aim of this study is to compare how the VCV and PCV modes and using a LMA affect the pulmonary mechanics, the gas exchange and the cardiovascular responses in patients who are undergoing gynecological laparoscopy. Methods: Sixty female patients were randomly allocated to one of two groups, (the VCV or PCV groups). In the VCV group, baseline ventilation of the lung was performed with volume-controlled ventilation and a tidal volume of 10 ml/kg ideal body weight (IBW). In the PCV group, baseline ventilation of the lung using pressure-controlled ventilation was initiated with a peak airway pressure that provided a tidal volume of 10 ml/kg IBW and an upper limit of 35 cmH2O. The end-tidal CO2, the peak airway pressures (Ppeak), the compliance, the airway resistance and the arterial oxygen saturation were recorded at T1: 5 minutes after insertion of the laryngeal airway, and at T2 and T3: 5 and 15 minutes, respectively, after CO2 insufflation. Results: The Ppeak at 5 minutes and 15 minutes after CO2 insufflation were significantly increased compared to the baseline values in both groups. Also, at 5 minutes and 15 minutes after CO2 insufflation, there were significant differences of the Ppeak between the two groups. The compliance decreased in both groups after creating the pneumopertoneim (P < 0.05). Conclusions: Our results demonstrate that PCV may be an effective method of ventilation during gynecological laparoscopy, and it ensures oxygenation while minimizing the increases of the peak airway pressure after CO2 insufflation. ��� the Korean Society of Anesthesiologists, 2011

Septicaemia due to a Proteus infection in a Humboldt penguin (Spheniscus humboldti)

A 2-year-old male Humboldt penguin (Spheniscus humboldti) died after a very brief period of illness at a zoo aquarium; the penguin showed sudden depression, anorexia, dyspnoea, and had recurrent melena a day prior to death. The gross examination revealed an extensive bilious effusion in the abdominal cavity due to a gallbladder rupture. Moreover, abscess formation, purulent exudate, severe congestion, and haemorrhages were observed in the trachea and parenchymal organs such as the kidneys and the lungs. A histopathological examination revealed a fibrin deposition with a severe haemorrhage and secondary infiltration of chronic-active inflammatory cells in the parabronchi, atria, and air capillaries and blood vessels of the lungs as well as in most of the parenchymal organs. Moreover, Gram-negative bacilli were found in the lumen of the gastrointestinal tracts including the small and large intestines accompanied by severe epithelial necrosis and the capsule of the liver. Especially, bile pigments were microscopically observed in the whole liver, which indicated a gallbladder rupture. Samples collected from the trachea, lungs, and blood were cultured on a blood agar, and the pure colonies of Proteus genus were isolated. Proteus mirabilis, P. penneri, P. vulgaris, and P. cibarius were identified with polymerase chain reaction (PCR). As a result, the diagnosis was confirmed as Proteus septicaemia. To our knowledge, this is the first report of concomitant infection by different Proteus species that eventually resulted in septicaemia in a Humboldt penguin, and it will provide valuable information for zoo veterinarians for its diagnosis as well, since Humboldt penguins are the most widely found penguins in zoos and Proteus septicaemia in the penguins has, to the best of our knowledge, not been reported as yet.1