Biomedical subjects

Ruben Urena

Publications and source records attributed to Ruben Urena.

5 recordsLinked to original sources

PubMed2006

Case report: laparoscopic management of massive chylous ascites after salvage laparoscopic retroperitoneal lymph-node dissection.

Chylous ascites is an infrequent complication of retroperitoneal surgery. We describe a patient who suffered massive chylous ascites after simultaneous pneumonectomy and laparoscopic excision of a post-chemotherapy tumor mass. After conservative management failed, exploratory laparoscopy identified the site of the leak, which was clipped and closed with fibrin glue. There has been no recurrence in the ensuing 5 years.

Adolescent↗

PubMed2005

Does prolonged pneumoperitoneum affect oxidative stress compared with open surgical procedures?

BACKGROUND AND PURPOSE: As laparoscopic surgery has evolved, it has become part of the urologic surgical armamentarium and is now used to perform more complex procedures. Carbon dioxide, used to create pneumoperitoneum, produces physiologic changes in various organs, including the kidneys. Such changes are associated with altered redox status because of the release of free radicals and changes in oxidative stress signals. It is unknown whether prolonged pneumoperitoneum is associated with an increase in oxidative stress compared with open surgery. The objective of this study was to compare oxidative stress in patients undergoing urologic laparoscopic and open operations. PATIENTS AND METHODS: Urine samples were obtained immediately preoperatively, immediately postoperatively, and at 6 and 18 hours after surgery from 10 patients who underwent urologic laparoscopic surgery and 10 patients who underwent open surgery. Concentrations of the oxidative stress marker isoprostane (8- iso-prostaglandin F2a) were measured, and the results were analyzed with respect to clinical factors associated with the type of surgery. RESULTS: Urinary isoprostane concentrations (mean +/- SEM) in the laparoscopic and open groups showed an increase immediately after surgery to 189.0 +/- 64.2% and 141.1 +/- 45.8% of the preoperative values, respectively. A decrease in isoprostane was subsequently observed in both groups at 6 hours postoperatively, with preoperative values restored at 18 hours postoperatively (126.3 +/- 19.7% and 89.5 +/- 55.9% at 6 and 18 hours, respectively, in the laparoscopic group and 130.7 +/- 41.6% and 88.7 +/- 20.4% at 6 and 18 hours, respectively, in the open-surgery group). Although in both groups the peak PGF 2a concentration was observed immediately (0 hours) postoperatively, no significant differences were observed between the groups at 0, 6, and 18 hours. In the laparoscopic-surgery group, the mean increase tended to be higher and the decrease to be less prolonged than in the open-surgery group. CONCLUSION: Oxidative stress, as measured by urinary 8-iso-prostaglandin F2a, is produced by both laparoscopic and open urologic surgery. The findings of our nonrandomized study suggest a pattern of increased oxidative stress postoperatively with either type of surgery, with subsequent return almost to preoperative levels. Prolonged laparoscopic operative time did not affect oxidative stress levels.

Biomarkers↗

PubMed2004

Retrograde ureteroscopic endopyelotomy.

Several different procedures can be used to treat UPJ obstruction. Retrograde ureteroscopic endopyelotomy provides a safe and adequate first line of treatment for this condition. With the advent of smaller ureteroscopes and ancillary devices, this technique has evolved to include children. Adherence to strict endourologic principles and direct visualization make retrograde ureteroscopic endopyelotomy a safe and effective treatment modality. This procedure represents an extension of the basic endoscopic skills of the urologist, creating a short learning curve and wide margin of safety.

Clinical Trials as Topic↗

PubMed2004

Donor nephrectomy in the era of hand-assisted laparoscopic urologic surgery.

Living-donor nephrectomy has traditionally been performed through a flank incision with or without rib resection or by an anterior extraperitoneal incision, both of which reduce the willingness of potential donors to undergo the procedure. The first successful human laparoscopic donor nephrectomy was reported in 1995. In order to reduce warm ischemia and operative time and to make the operation safer and easier, some laparoscopic surgeons have used hand assistance. The authors describe their technique for this operation and review the results.

Equipment Design↗

PubMed2004

Laparoscopic partial nephrectomy of solid renal masses without hilar clamping using a monopolar radio frequency device.

PURPOSE: Partial nephrectomy is currently recommended for most amenable solid renal tumors, especially if they are exophytic and less than 4 cm. We reviewed our initial experience with laparoscopic partial nephrectomy for solid renal masses without clamping the renal vasculature using a monopolar device that uses radio frequency energy with low volume saline irrigation for simultaneous blunt dissection, hemostatic sealing and coagulation of the renal parenchyma (TissueLink, TissueLink Medical, Inc., Dover, New Hampshire). MATERIALS AND METHODS: From September 2002 to April 2003, 10 patients underwent transperitoneal laparoscopic partial nephrectomy, including 9 with solid renal masses and 1 with a complex cyst. In all cases the renal hilum was dissected and the renal vessels were isolated but none had renal vascular clamping. The TissueLink DS dissecting sealer or Floating Ball (TissueLink Medical, Inc.) was used to dissect the tumor free bluntly, while simultaneously sealing and coagulating bleeders. RESULTS: Mean patient age was 54.6 years (range 42 to 72). Mean American Society of Anesthesiologists score was 2.3 (range 2 to 4). Mean tumor size was 3.9 cm (range 2.1 to 8). The mass had a peripheral location in 7 cases and a central location in 3. Mean operative time was 232 minutes (range 144 to 280) and mean blood loss was 352 ml (range 20 to 1000). One patient received blood transfusion and all tumor margins were negative. Mean hospital stay was 1.7 days (range 1 to 5) and pain medication use was minimal. One patient had a brief period of urine leakage from the lower pole calix, which was managed successfully by ureteral stenting and Foley catheter drainage of the bladder. CONCLUSIONS: Laparoscopic partial nephrectomy can be performed without renal vascular clamping. TissueLink technology allows complete tumor resection and provides adequate parenchymal hemostasis of the tumor bed. Its scant tissue charring production does not interfere with the pathological assessment of the tumor margin status.

Adult↗