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R V Clayman

Publications and source records attributed to R V Clayman.

At least 163 records · Page 9Linked to original sources
PubMed1995

A new renal tourniquet for open and laparoscopic partial nephrectomy.

PURPOSE: We describe a novel double loop renal parenchymal tourniquet for obtaining hemostasis during open and laparoscopic partial nephrectomy. METHODS: One loop is positioned around the upper and 1 around the lower renal poles, thus securely entrapping the kidney. During partial nephrectomy the corresponding loop is double looped and cinched, thus achieving a tourniquet effect. The renal artery is not occluded. Intraoperative renal hypothermia is not required. RESULTS: The renal tourniquet was used clinically during 6 open and 1 laparoscopic partial nephrectomies. Furthermore, during laparoscopic nephrectomy (5 porcine and 1 clinical cases) the double loop apparatus allowed for improved maneuverability of the kidney. CONCLUSIONS: The novel renal tourniquet affords adequate renal parenchymal hemostasis during open and laparoscopic partial nephrectomy.

Animals↗
PubMed1995

The extraperitoneal approach and subcutaneous emphysema are associated with greater absorption of carbon dioxide during laparoscopic renal surgery.

PURPOSE: We investigated the association of carbon dioxide absorption with the approach (transperitoneal versus extraperitoneal) and other factors during laparoscopy. MATERIALS AND METHODS: Carbon dioxide elimination during laparoscopic renal surgery was retrospectively calculated in 63 patients. RESULTS: Carbon dioxide elimination increased with time. Multiple factorial analysis revealed that subcutaneous emphysema and the extraperitoneal approach were independently associated with a greater increase in carbon dioxide elimination. Pneumothorax and pneumomediastinum were more common during extraperitoneal procedures. CONCLUSIONS: Carbon dioxide absorption during laparoscopic renal surgery increases with time, and is greatest in patients treated through an extraperitoneal approach and in those with subcutaneous emphysema. Nonetheless, with attentive ventilatory management adverse sequelae of hypercapnia can be avoided.

Absorption↗
PubMed1995

Advances in urological laparoscopy.

PURPOSE: Since its introduction 5 years ago, almost all open urological procedures have been performed laparoscopically. We provide an in-depth critical review. MATERIALS AND METHODS: More than 200 articles on laparoscopic urology were reviewed. All laparoscopic procedures were divided into clinically established, clinically anecdotal and laboratory procedures. Comparisons between the laparoscopic and open method were carefully analyzed. RESULTS: There were 5 clinically established procedures identified. In general, the laparoscopic procedures were as efficacious but less morbid and required less convalescence than their open counterparts; however, none was less costly. CONCLUSIONS: Despite the time-consuming and costly nature of laparoscopy, the decreased morbidity and brief convalescence that are the hallmarks of minimally invasive surgery are evident and well documented. Further dissemination of laparoscopic skills through postgraduate urology training programs and during urology residency is of the utmost importance.

Cystectomy↗
PubMed1995

Carbon dioxide absorption during laparoscopic pelvic operation.

BACKGROUND: Several factors may influence the degree of carbon dioxide (CO2) absorption during laparoscopy. Hypercapnia as a result of excessive CO2 absorption may have adverse clinical effects. STUDY DESIGN: To identify factors associated with increased CO2 absorption, we retrospectively calculated the CO2 elimination in 65 adult patients who underwent operative pelvic laparoscopy. Increases in CO2 elimination were assumed to be indicative of CO2 absorption. The most commonly performed procedures were bladder neck suspension and pelvic lymphadenectomy. The median insufflation time was 165 minutes. An extraperitoneal approach was taken in 32 percent of the patients. RESULTS: Of patients evaluated with postoperative roentgenograms of the chest, 35 percent had subcutaneous emphysema and 9 percent had pneumomediastinum with or without pneumothorax. Multiple factorial analysis of the variance revealed that the extraperitoneal approach, development of subcutaneous emphysema, and increased duration of insufflation were independently associated with a greater increase in peak CO2 elimination. Insufflation time and subcutaneous emphysema had stronger effects in the extraperitoneal group. CONCLUSIONS: The risk factors for hypercapnia can be identified. Careful consideration of the patient's ability to tolerate hypercapnia should be made when planning extraperitoneal laparoscopy, especially if the procedure is likely to be prolonged. The clinical development of subcutaneous emphysema should alert the surgeon to the possibility of subsequent hypercapnia.

Absorption↗
PubMed1995

Effect of piezoelectric energy on porcine kidneys using the EDAP LT.02.

EDAP International (Cambridge, Massachusetts) has developed a new piezoelectric lithotripter (LT.02) that differs from their earlier model (LT.01) in two important respects: method of stone visualization and available power. The LT.02 provides both in-line fluoroscopy as well as real time ultrasound. The maximum energy is 1400 Bar (compared with 1100 Bar in the LT.01). The purpose of this study was to determine whether treatment with the EDAP LT.02 piezoelectric lithotripter would cause significant renal injury in minipigs. Accordingly, 18 minipigs were divided into 3 groups of 6. Each group received a treatment of 20, 40 or 60 minutes; the power level and shock wave frequency were kept at maximal levels throughout the treatment period. Three pigs from each group were sacrificed at 72 hours (acute). The remaining 9 pigs were sacrificed 1 month following LT.02 treatment (chronic). Histopathologic analysis of the treated kidney revealed that 33% of the 9 acute pigs developed a small capsular hematoma, whereas 66% showed only a small parenchymal contusion ( < or = 1% of total renal volume). Among the chronic pigs, 66% had a small cortical scar, whereas 33% had no macroscopic pathology. Despite the differences in the number of shock waves delivered, these changes were evenly distributed among the 3 groups. Histologic acute changes included circumscribed areas of hemorrhagic infarction, vascular thrombosis with recanalization and focal tubular obstruction and damage. At 30 days, however, these acute injuries had completely resolved in 3 pigs and were only notable as minute areas of focal tubular loss in 6 pigs.

Animals↗
PubMed1994

Endoscopic management of persistent lymphocele following laparoscopic pelvic lymphadenectomy.

OBJECTIVE: To report an alternative form of management of a persistent lymphocele that was unresponsive to percutaneous drainage and ethanol sclerotherapy. METHODS: Herein is described the technique of dilating the previously established percutaneous drainage tract to facilitate insertion of a flexible ureteroscope. Through this instrument electrosurgical fulguration of the lymphocele cavity was performed. RESULTS: The patient had complete resolution of the lymphocele cavity on computed tomography (CT) scan and remains asymptomatic at six months of follow-up. CONCLUSIONS: Flexible ureteroscopic access and fulguration of a lymphocele proved to be a safe and effective method of obliterating the lymphocele cavity.

Endoscopy↗
PubMed1994

Transperitoneal nephrectomy for benign disease of the kidney: a comparison of laparoscopic and open surgical techniques.

OBJECTIVE: The objective of this study was to compare the results of laparoscopic nephrectomy for benign disease to open surgical nephrectomy for benign disease. METHODS: Twenty consecutive patients undergoing laparoscopic nephrectomy for benign disease were compared with 23 patients undergoing open surgical nephrectomy for benign disease and with 29 patients undergoing a donor nephrectomy. Data were collected in the following areas: patient age, anesthetic risk, operative time, estimated blood loss, postoperative time to resume oral intake, parenteral analgesics, oral analgesics, hospital stay, complications, and convalescence. Information was obtained through chart review, telephone interviews, and mailed questionnaires. RESULTS: Compared with open surgical nephrectomy, laparoscopic nephrectomy resulted in a statistically significant longer operative time; however, it afforded a statistically significant decrease in postoperative ileus (open group), hospital stay (both groups), oral analgesics (donor group), and convalescence (both groups). The incidence of complications was 15 percent in the laparoscopic group and 0 percent in the two open surgical groups; the majority of complications occurred during the initial seven laparoscopic procedures. CONCLUSIONS: Laparoscopic nephrectomy is a more time-consuming procedure than open surgical nephrectomy. Also, early in one's experience with this technique, the complication rate is higher than with open surgery. However, despite the newness of the technique, it results in significant benefits to the patient: decreased postoperative pain, shorter hospitalization, and more rapid convalescence.

Adult↗
PubMed1994

Advances in laparoscopic urology, Part I. History and development of procedures.

Many of the recent applications of laparoscopy to urologic surgery have demonstrated the feasibility of these techniques to complete the intended diagnostic or therapeutic objectives and provide the patient with a more comfortable and shorter recuperative period. Ongoing laboratory and clinical research continues to expand the field of laparoscopic urologic surgery in terms of therapeutic and reconstructive techniques. The second part of this review will explore the more innovative applications of laparoscopic urology and the impact this may have on the practice and art of urology.

Adrenalectomy↗
PubMed1994

Retroperitoneoscopy: the Washington University Medical School experience.

OBJECTIVE: To describe our initial experience with balloon dilatation of the retroperitoneum. METHODS: In 12 patients undergoing laparoscopic renal surgery, the retroperitoneum was dilated using the technique of balloon dilatation. This technique is described and the operative procedure performed in each patient is outlined. The postoperative recovery data and complications are also presented. RESULTS: This procedure provided excellent exposure of the anatomic structures within the retroperitoneal space and simplified the surgical dissection by staying out of the abdominal cavity. CONCLUSIONS: Access to the retroperitoneal space is easily and quickly performed utilizing the technique of balloon dilation and may minimize the risk of injury to peritoneal organs.

Adult↗
PubMed1994

Comparison of retrograde endo-pyelotomy and endo-balloon rupture of the ureteropelvic junction in a porcine model.

Excellent results and durable success have been achieved with antegrade and retrograde endo-pyelotomy for treating primary and secondary ureteropelvic junction obstruction. Recently, a 30F dilating balloon was used to rupture the ureteropelvic junction (ENDOBRST) with encouraging results. While balloon distention of the ureteropelvic junction is a technically simpler procedure than endo-pyelotomy, clinical and laboratory data comparing the 2 methods are lacking. In an acute and chronic animal study we compared endo-pyelotomy via a ureteral cutting balloon incision to balloon rupture (that is 30F) of the normal ureteropelvic junction in each of 20 female farm pigs. Eight pigs were harvested acutely after treatment, and a macroscopic and histological examination of the treated ureteropelvic junction was completed. In 11 chronic pigs after endo-pyelotomy a 7F double pigtail ureteral stent was placed bilaterally and then removed after 6 weeks. Evaluation in the chronic group consisted of a furosemide washout renogram and retrograde pyelogram immediately preoperatively and 6 weeks after stent removal. The animals were likewise harvested 6 weeks after stent removal. One control pig underwent passage of the balloon cutting catheter and balloon dilating catheters without activation or dilation, respectively. Ureteral stents were placed bilaterally for 6 weeks and the pig was otherwise treated similarly to the other chronic study animals. In the acute group all ureters after endo-pyelotomy demonstrated retroperitoneal extravasation of contrast material. At harvest the ureters had been cleanly incised along a length of 3 to 4 cm. through the adventitial layer. In contrast, the balloon treated ureters showed free retroperitoneal extravasation in only half of the animals. Among the balloon treated ureters 7 of 8 had a linear tear of varying length (1 to 5 cm.) involving all but a thin adventitial layer of tissue. Histologically, the endo-pyelotomy ureters demonstrated a clean, linear transmural incision with virtually no destruction of surrounding tissue in 6 cases. In the remaining 2 cases an incision into but not completely through the muscular layer was observed. The balloon treated ureters showed a perforation through the muscular wall in 7 cases. However, periureteral hemorrhage and urothelial loss were common findings. In the chronic group infection and continued urine extravasation from the endo-pyelotomy site resulted in a 45% mortality rate. Of the surviving 6 pigs 83% of the balloon treated and 67% of the endo-pyelotomy pigs had a patent ureteropelvic junction by retrograde pyelogram and renogram. Histologically, the 2 sides were indistinguishable, with both showing mild fibrosis and chronic inflammation.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1994

Adrenal involvement from renal cell carcinoma: predictive value of computerized tomography.

Although adrenal involvement from renal cell carcinoma is rare, removal of the adrenal during radical nephrectomy continues to be standard practice. To assess the actual need for adrenalectomy, we elected to evaluate whether malignant involvement of the adrenal gland could be reliably diagnosed preoperatively by a computerized tomogram (CT) of the abdomen. A blinded retrospective review of preoperative abdominal CT in 157 patients with renal cancer revealed an abnormality of the ipsilateral adrenal gland in 38. Histopathology confirmed malignant involvement of the adrenal in 10 patients. Significantly, all 119 adrenal glands judged to be normal on the preoperative CT were confirmed to be uninvolved by the renal cancer on histopathological study. We conclude that abdominal CT is reliable in the preoperative evaluation of the ipsilateral adrenal gland and assessment of its noninvolvement with renal carcinoma. In such cases adrenal sparing nephrectomy may be considered (76% of our patients). None of these 119 patients had either macroscopic or microscopic adrenal involvement. When the adrenal is not identified, displaced or enlarged on CT (24% of our patients) adrenalectomy should be routinely performed as part of radical nephrectomy. Even in this select group adrenal involvement was present in only 26% of the cases.

Adrenal Gland Neoplasms↗
PubMed1994

Endo-ureteroplasty with a free urothelial graft.

Endo-urological therapy for ureteral strictures is usually limited to lesions 1 cm. or shorter. In an attempt to develop an endo-urological approach to treat longer ureteral strictures, we studied the clinical use of a transurethrally harvested free graft of bladder urothelium placed into the incised stricture bed. A total of 6 patients with ureteral strictures 1.5 to 8 cm. long (average 2.9 cm.) underwent endo-surgical management via free urothelial graft endo-ureteroplasty. Operative time averaged 5.5 hours. Complications included urinoma in 1 patient, hyponatremia in 1 and a postoperative renal pseudoaneurysm in 1. Four patients had long-term (that is 22 months or longer) successful results. Free urothelial graft endo-ureteroplasty, while tedious, may be a useful endo-surgical technique for treatment of long ureteral strictures.

Adult↗
PubMed1994

Pediatric laparoscopy: quo vadis? A view from the outside.

The impact of laparoscopy on all types of surgery has been revolutionary. The general surgeon, gynecologist, colorectal surgeon and urologist have all been affected by developments in this area. Until now, these advances have almost been uniformly limited to adults. However, the miniaturization of instrumentation, improvement of endoscopic visualization and camera technology, and recent pioneering efforts of a few individuals have made these same adult procedures possible in adolescents, children and infants. However, for each innovative procedure, the question must be answered whether this truly represents an advance or merely a technological marvel. In this regard, careful studies need to be conducted comparing the surgical and laparoscopic outcomes for each procedure in patients of similar age from the standpoint of efficacy, cost and patient morbidity. These objective data will provide the answer to the question: "It's new, but is it better?"

Adolescent↗
PubMed1994

Laparoscopic excision of müllerian duct remnant.

Müllerian duct cysts are rare but they can cause significant abdominal and vesical symptoms. Excision of these cysts entails a major surgical effort that usually involves a transvesical approach. To our knowledge we report the first case of successful laparoscopic excision of a large 7 cm. müllerian duct cyst with preservation of potency and continence.

Cysts↗
PubMed1994

Optimal therapy for the distal ureteral stone: extracorporeal shock wave lithotripsy versus ureteroscopy.

Extracorporeal shock wave lithotripsy (ESWL not equal to) is the optimal therapy for renal calculi less than 2 cm. in diameter and for proximal ureteral calculi. Controversy continues over the initial approach to distal ureteral calculi (that is below the bony pelvis): in situ ESWL versus ureteroscopy. Since February 1990, 76 distal ureteral calculi were treated at our institution using either in situ ESWL (Dornier HM3 ESWL with a Stryker frame modification in 27 patients or Siemen's Lithostar electromagnetic ESWL in 22) or ureteroscopy (27 patients). Patient age and stone size were similar among the groups. All ESWL treatments were performed with the patient under intravenous sedation and on an outpatient basis. Stone-free rates were 96% for the HM3 device, 84% for the Lithostar and 100% for ureteroscopy. Retreatment was required in 3 Lithostar cases (14%) and 1 HM3 case (4%). When compared to ESWL ureteroscopy for distal ureteral stones was more time-consuming, entailed routine placement of a ureteral stent, often required general anesthesia, more often led to hospitalization and doubled the convalescence period. From a cost standpoint, ESWL on an HM3 unit was a few hundred dollars more expensive than ureteroscopy. In summary, we believe that in situ ESWL provides optimal first line therapy for distal ureteral calculi, while ureteroscopy is better reserved as a salvage procedure should ESWL fail.

Adult↗
PubMed1994

Percutaneous stone removal with the patient in a flank position.

We report a case of percutaneous removal of a staghorn calculus that was accomplished in a morbidly obese patient while he was in a full flank position. In this position, the stone could be successfully accessed and fragmented without compromising the pulmonary status of the patient.

Combined Modality Therapy↗