Laparoscopic surgery in the obese: Safe techniques
Increases in atelectasis, wound infection, and other risks after laparotomy point to laparoscopy as the safer route.
Techniques to enhance visualization
Excess adipose tissue occupies the pericolic, omental, mesenteric, and retroperitoneal spaces in obese patients, obscuring visualization of intraperitoneal and retroperitoneal structures.
Preoperative mechanical bowel preparation can deflate the bowel and enhance visualization (TABLE 2). At times, an extra ancillary trocar for placement of a bowel retractor also can improve visualization.
In the morbidly obese, insufflation pressure of 15 mm Hg will sometimes produce poor visualization. Obese patients generally tolerate this pressure reasonably well, but increasing it to improve visualization can make adequate oxygenation impossible.
Gasless laparoscopy—in which a mechanical retractor is attached from the table to the patient’s anterior abdominal wall—may help improve pulmonary mechanical parameters. Unfortunately, this technique often produces poorer visualization than insufflation at normal pressure.
A new technique that combines approaches may help avoid the need to convert to laparotomy.12 In this “Foley lap lift,” a 14-French Foley catheter is passed through the anterior abdominal wall, and the balloon is inflated. The catheter then is elevated and clamped to a retractor holder attached to the angled foot of the bed. This upward traction with continuous gas flow at normal pressure improves visualization without pulmonary compromise.
TABLE 2
Techniques to enhance visualization
|
| *See page 70 for details |
Close port sites at the fascial level
The risk of bowel herniation through a trocar site is higher in obese patients than the general population because of the greater intraabdominal pressures. Increases in atelectasis from diminished functional residual capacity also predispose the obese patient to postoperative pulmonary complications and can lead to recurrent Valsalva (cough) and subsequent bowel herniation.
Given these risks, it is imperative that all port sites 10 mm or larger be closed at the fascial level. Unfortunately, the distance from the anterior abdominal wall to the fascia underlying these sites makes direct visualization and closure almost impossible.
Fortunately, several fascial closure devices are available and are reasonably inexpensive and easy to use. When using them, be sure to maintain the other port sites, as closure requires direct visualization and a second instrument.
Postoperative strategies
Successful postoperative care builds on preoperative and intraoperative tactics.
Perform aggressive pulmonary toilet
With intraoperative decreases in functional residual capacity, postoperative atelectasis is likely to be profound, with a potential for ventilation/perfusion mismatch and hypoxemia.
Aggressive pulmonary toilet including regular incentive spirometry and deep breathing and coughing exercises is important to reinflate dependent lung regions. Pulse oximetry with sufficient supplementary oxygen also is important to maintain adequate saturation.
Encourage early ambulation
This requires adequate but not oversedating analgesia, early catheter removal, and a motivated nursing staff.
Early ambulation is associated with fewer episodes of deep venous thrombosis, pulmonary complications, and ileus, and also eases pain management.
Continue thrombosis prophylaxis with sequential compression devices, subcutaneous heparin, or both, until the patient is spending most of her time out of bed.
Dr. Robinson reports no relevant financial relationships.
Dr. Isaacson serves on the speakers bureau for Karl Storz Endoscopy.
