35 Yr female with controlled thyrotoxicosis and carcinoma rectum undergoing laparoscopic abdomino perineal resection found to have decreased blood pressure and decreased heart rate, flat end tidal CO2 found to have reduced from 40 To 10 mm of Hg and mill wheel murmur. What is the most likely cause (AIIMS Nov 2009)
1). An air embolism is caused by gas bubbles in a vascular system.
2). Gas embolism in diving
Gas embolism is a diving disorder suffered by SCUBA divers and can happen in two distinct ways:
a. Pulmonary barotrauma: Air bubbles enter the bloodstream as a result of gross trauma to the lining of the lung following a rapid ascent while holding the breath; the air held within the lung expands to the point where the lungs burst (pulmonary barotrauma).
b. Decompression sickness (DCS): Air bubbles precipitate out into the bloodstream if the gas dissolved in the blood at pressure is not allowed sufficient time to out-gas on ascent. The symptoms may be subtle and not immediately noticeable.
1). Recompression is the most effective treatment of an air embolism. Normally this is carried out in arecompression chamber.