Detrimental blood flow and breathing changes are common in obese patients undergoing laparoscopic, or “keyhole,” gastric bypass surgery. Therefore, invasive monitoring with a blood vessel catheter may be warranted to assure a safe operation, new research suggests.

As reported in the Archives of Surgery, Dr. Sebastiano Cassaro, at Cabrini Medical Center in New York, and colleagues performed laparoscopic gastric bypass surgery on 13 obese patients. The patients’ blood flow and breathing changes were monitored during surgery with a device called a pulmonary artery catheter.

A variety of changes in blood vessel and lung pressures were noted soon after the abdomen was filled with carbon dioxide, which occurs at the beginning of all laparoscopic operations. In addition, the patients’ blood became more acidic.

Switching the operating table to the head up/feet down position corrected many of the changes, but did not improve blood acidity. Further blood vessel changes occurred at the end of the operation when the carbon dioxide was released from the abdomen

As with other high-risk patients undergoing laparoscopic surgery, obese patients with significant heart and lung problems may benefit from invasive monitoring,” Cassaro’s group concludes.

SOURCE: Archives of Surgery, March 2005.