Improving Patient Positioning To Reduce Complications In Prone Percutaneous Nephrolithotomy.
Published 2009 · Medicine
Percutaneous nephrolithotomy (PCNL), the goldstandard treatment for complex and=or large stone burden, is traditionally performed with the patient in the prone position. There are concerns regarding PCNL in the prone position, especially in the morbidly obese patients and those with compromised cardiopulmonary status and with skeletal deformities. These are over and above the recognized surgical complications of PCNL. Nevertheless, prone PCNL is the classical second stage, after the standard first stage (lithotomy position) where retrograde contrast studies and=or ureteroscopy take place. In the prone position during PCNL, there is reduced lung compliance caused by reduced chest wall and diaphragmatic excursion as a result of abdominal compression. There is also a reduction in cardiac output. Patients have traditionally been placed on pillows and jelly rolls, with or without a roll bar under the rib cage to push the kidneys more posteriorly. All of these pose significant challenges to the anesthetist, while there are no relevant published studies touching these issues. During prone procedures there is also the issue of keeping the neck neutrally aligned and monitoring the endotracheal tube, to ensure no kinking of the tube occurs. Traditionally, the head is supported on a pillow to try to keep neutral neck alignment, or the head may be laterally rotated and rests on the pillow. However, musculoskeletal complications such as a stiff neck, hoarseness caused by vocal cord compression, and brachial plexopathies are reported with prone surgery, as a result of patient positioning. To address some of these issues and complications, supine and lateral position PCNL as well as PCNL in the modified Valdivia position have become more popularized. Although we have experience in performing PCNL in all of these positions, we have developed improvements in patient positioning to reduce the risk of anesthetic and musculoskeletal complications during prone PCNL.