Effect of a short-acting NO donor on bubble formation from a saturation dive in pigs.
It has previously been reported that a nitric oxide (NO) donor reduces bubble formation from an air dive and that blocking NO production increases bubble formation. The present study was initiated to see whether a short-acting NO donor (glycerol trinitrate, 5 mg/ml; Nycomed Pharma) given immediately before start of decompression would affect the amount of vascular bubbles during and after decompression from a saturation dive in pigs. A total of 14 pigs (Sus scrofa domestica of the strain Norsk landsvin) were randomly divided into an experimental (n = 7) and a control group (n = 7). The pigs were anesthetized with ketamine and alpha-chloralose and compressed in a hyperbaric chamber to 500 kPa (40 m of seawater) in 2 min, and they had 3-h bottom time while breathing nitrox (35 kPa O(2)). The pigs were all decompressed to the surface (100 kPa) at a rate of 200 kPa/h. During decompression, the inspired Po(2) of the breathing gas was kept at 100 kPa. Thirty minutes before decompression, the experimental group received a short-acting NO donor intravenously, while the control group were given equal amounts of saline. The average number of bubbles seen during the observation period decreased from 0.2 to 0.02 bubbles/cm(2) (P < 0.0001) in the experimental group compared with the controls. The present study gives further support to the role of NO in preventing vascular bubble formation after decompression.
Møllerløkken
A
A
Department of Circulation and Medical Imaging, Faculty of Medicine, Norwegian University of Science and Technology, Olav Kyrres gt. 3, N-7489 Trondheim, Norway. andreas.mollerlokken@ntnu.no
Berge
V J
VJ
Jørgensen
A
A
Wisløff
U
U
Brubakk
A O
AO
D000818:Animals; D003665:Decompression Sickness / Q000209:etiology / Q000503:physiopathology* / Q000628:therapy*; D004242:Diving / Q000009:adverse effects; D004618:Embolism, Air / Q000209:etiology / Q000503:physiopathology* / Q000628:therapy*; D006321:Heart / Q000187:drug effects; D008297:Male; D009206:Myocardium / Q000378:metabolism*; D020030:Nitric Oxide Donors / Q000008:administration & dosage*; D010088:Oxidoreductases / Q000008:administration & dosage*; D010100:Oxygen / Q000378:metabolism; D013552:Swine; D016896:Treatment Outcome
D020030:Nitric Oxide Donors; D010088:Oxidoreductases; C077366:glyceryl trinitrate reductase; D010100:Oxygen