Intercostal vessels and nerves are at risk for injury during supracostal percutaneous nephrostolithotomy.

PURPOSE: We characterized key intercostal anatomical relationships relevant to supracostal percutaneous nephrostolithotomy using anatomical dissection. MATERIALS AND METHODS: We performed 20 cadaveric dissections of the 11th intercostal space to characterize key anatomical relationships relevant to percutaneous upper pole renal access. Specific data recorded included intercostal rib distance at the lateral border of the paraspinous muscles, and the mid scapular and posterior axillary lines. We also recorded the distance between the 12th and 11th ribs to the intercostal nerve, artery and vein at the same 3 sites. RESULTS: The average intercostal distance was 21, 23 and 26 mm at the lateral border of the paraspinous muscles, and the mid scapular and posterior axillary lines, respectively. The intercostal nerve was exposed to injury in 85%, 100% and 100% of patients at the 3 sites, respectively. The intercostal artery was exposed below the 11th rib in 30%, 60% and 70% of cadavers, respectively, and it was 6 mm from the rib in 25% of interspaces. The intercostal vein, which was exposed below the 11th rib in 0%, 5% and 10% of cadavers, respectively, was least likely to be injured. CONCLUSIONS: Intercostal vessels are at risk for damage during percutaneous nephrostolithotomy in a significant number of patients. Access placement lateral to the paraspinous muscles and in the lower half of the 11th intercostal space may decrease damage to the intercostal artery and nerve. Injury to the intercostal vessels and nerve may explain the increased risk of bleeding and pain during supracostal percutaneous nephrostolithotomy. Minimizing injury may decrease blood loss and pain.

Synthetic torso for training in and evaluation of urologic laparoscopic skills.

BACKGROUND: The expanding use of advanced minimally invasive surgical techniques demands more advanced training methods, objective measures of resident performance, and more realistic and anatomically correct training models. MATERIALS AND METHODS: A new synthetic torso for urologic laparoscopy training was developed and assessed. The trainer, Lapman, was based on the Visible Human Model and has the exact shape of a human torso. The torso models the outer shape of the body and the abdominal and pulmonary cavities. Animal or synthetic models of the abdominal organs may be placed in the abdominal cavity. An abdominal wall provides access and seals the cavity and can be replaced after repeated punctures with laparoscopic instruments. The thoracic cavity connects to a pneumatic pump to simulate breathing. In order to render realistic mechanic properties, the torso is cast of materials with elastic properties similar to those of soft tissue and incorporates a synthetic skeleton. These similar mechanical properties and the thoracic insufflation create realistic ventilatory motion simulation. RESULTS: Twenty-five individuals--medical students, residents, and attending urologists--participated in a study comparing Lapman with a standard training box. Lapman presented several advantages over the traditional training box, specifically with regard to internal and external views and the incorporation of a realistically shaped abdominal wall. A significant and recurrent theme was the value of the synthetic wall as a tool to gain a greater appreciation of the importance of port placement. Study participants at all levels of training appreciated that Lapman gives a more realistic approximation of the operative procedure. CONCLUSIONS: The novelty of the trainer consists in its anatomic shape, realistic mechanical properties, and ventilatory simulation. This paper reports on its design, construction, and preliminary tests.

A practical and evidence-based approach to cardiovascular disease risk reduction.

Implementation of the numerous lifestyle and medical management options for secondary prevention of cardiovascular disease remains a daunting goal for primary care physicians and cardiologists alike. Despite the existence of expert consensus guidelines on cardiovascular prevention by the American College of Cardiology and the American Heart Association, therapies known to improve patient care and decrease morbidity and mortality remain underutilized. This review attempts to simplify cardiovascular risk reduction by summarizing key clinical trials in an "ABC" format. We believe that if health care providers and patients use such a format, important lifestyle and pharmacologic options will more likely be addressed.

In vitro comparison of changes in effective patient weight between purely laparoscopic and hand-assisted laparoscopic surgery.

BACKGROUND AND PURPOSE: Subclinical rhabdomyolysis (RM) has been reported to occur at a high frequency in patients who are undergoing hand-assisted laparoscopic (HAL) surgery. Compressive forces of the surgeon's hand pushing the patient down onto the operating table may increase the patient's effective weight, a factor that is correlated with risk of RM. The purpose of this study was to evaluate the changes in effective patient weight during pure laparoscopic (PL) and HAL surgery. MATERIALS AND METHODS: Using an in vitro model, 10 subjects performed translocation and knot tying tasks with both PL and HAL techniques. Changes in weight were monitored using a dynamic industrial scale with real-time digital recording. The means of the average changes in effective weight during the different tasks were compared using the Wilcoxon signed rank test with a P value of <0.05 considered significant. RESULTS: The mean of the average weight increases during translocation was 2.99 kg with HAL compared with 0.06 kg with PL (Z=4.3, P<0.05). The mean average weight increase during knot tying was 1.28 kg in HAL compared with 0.02 kg (Z=2.6, P<0.05) in PL. The mean maximum weight increase was 8.70 kg and 8.01 kg in HAL compared with 0.43 kg and 0.59 kg in PL during translocation and knot tying tasks, respectively (P<0.05 for each). CONCLUSIONS: HAL surgery results in a significant increase in effective patient weight compared with PL surgery. This increased effective weight during HAL surgery may increase the risk for subsequent RM.

Evaluation of water jet morcellation as an alternative to hand morcellation of renal tissue ablation during laparoscopic nephrectomy: an in vitro study.

OBJECTIVES: To evaluate the feasibility and safety of morcellation with a new prototype device that uses high-pressure water flow as a cutting/ablating tool and compare it with standard manual morcellation. METHODS: Ten porcine kidneys were morcellated with the new water jet device and ten with conventional manual morcellation. Morcellation in all cases was performed in commercially available entrapment bags. The two groups were evaluated for morcellation time, fragment size, and perforation rates (macroscopic and microscopic). RESULTS: The kidney size in both groups was similar. Morcellation was significantly (P <0.0001) faster in the water jet morcellator group than in the hand morcellation group (5.6 versus 11.9 minutes). The macroscopic evaluation after filling the entrapment bags with normal saline revealed 4 (40%) and 2 (20%) pinhole perforations in the water jet and hand morcellation groups, respectively. The microscopic evaluation revealed an 80% perforation rate in the water jet group and a 20% rate in the hand morcellator group. The size of the resulting fragments in the water jet group was not available, because the morcellated kidney was transformed in a semiliquid form. Therefore, cytology evaluation of the tissue was not possible. CONCLUSIONS: Water jet technology can be used to morcellate renal porcine tissue effectively. It is faster, but the problems of safety and histologic evaluation must be solved before this promising technology can be used in a clinical setting.

Vena caval transection during retroperitoneoscopic nephrectomy: report of the complication and review of the literature.

PURPOSE: Major vascular injuries are uncommon but serious complications of laparoscopic surgery. Early recognition and conversion to an open procedure may be required to avoid further complications. We report 2 cases in which the vena cava was transected during retroperitoneoscopic nephrectomy, and review the literature. MATERIALS AND METHODS: All urological laparoscopic cases from 1993 to 2002 at 2 institutions were reviewed to identify major vessel transection. Two cases of inadvertent transection of the vena cava were identified. Medical records were reviewed for clinical and pathological information to identify factors leading to this complication. A MEDLINE search was performed to identify similar reports in the literature. RESULTS: Two patients at 2 institutions were identified with vena caval transection during retroperitoneoscopic nephrectomy. In both cases the vena cava was misidentified as a renal vein. The injury was recognized immediately in both cases and an open repair was performed by vascular surgery. Both patients recovered with no sequelae. In both cases a rotated camera on an angled laparoscope in addition to the relative lack of retroperitoneal landmarks may have contributed to a loss of orientation within the operative field. A similar report of an aortic transection was also found in the literature. CONCLUSIONS: Disorientation of the operating surgeon within the surgical field secondary to rotation of the camera lens and lack of retroperitoneal landmarks may contribute to vena caval transection during retroperitoneoscopic nephrectomy. This injury has not been found in transperitoneal nephrectomy, likely because more intra-abdominal landmarks exist, aiding in maintenance of orientation. Prompt intraoperative recognition and repair of the transection results in a favorable outcome.