Biomedical subjects

David Le

Publications and source records attributed to David Le.

5 recordsLinked to original sources

PubMed2006

Robot-assisted laparoscopic resection of a type I choledochal cyst in a child.

Although the laparoscopic approach to the treatment of complex biliary disease is possible, it is technically challenging. In an attempt to overcome these difficulties, the da Vinci Surgical System (Intuitive Surgical, Sunnyvale, California) was used to facilitate the minimally invasive treatment of a type I choledochal cyst in a 5-year-old, 22 kg, girl. Complete resection of the choledochal cyst and a Roux-en-Y hepaticojejunostomy were performed using the robotic surgical system. Total robotic setup time (preparation, port placement, docking) was 40 minutes. Total procedure time was 440 minutes. Total robotic operative time was 390 minutes. No intraoperative complications or technical problems were encountered. At 6-month follow-up, the child is doing well with no episodes of cholangitis. Robot-assisted laparoscopic type I choledochal cyst resection appears safe and feasible. The three-dimensional visualization and wristed instrumentation greatly aids in the dissection of the cyst and in the biliary reconstruction.

Anastomosis, Roux-en-Y↗

PubMed2005

Differential effects of hyperosmotic challenge on interleukin-1-activated pathways in bovine articular cartilage.

Chondrocytes in situ experience fluctuations in extracellular osmolarity resulting from mechanical loading. The objective of this study was to determine whether hyperosmotic stress causes or exacerbates interleukin-1 (IL-1)-mediated effects in bovine articular cartilage. Disks of cartilage cut from the articular surface of calf radiocarpal joints were incubated for 24h in the presence or absence of IL-1 in Dulbecco's modified Eagle's medium adjusted to various osmolalities with sucrose or NaCl. Cyclooxygenase (COX)-2 levels in the cartilage were examined by Western blot. Culture media were assayed for prostaglandin E(2) (PGE(2)), nitrite as an indicator of nitric oxide (NO) production, and sulfated glycosaminoglycan as an indicator of proteoglycan degradation. We report the osmolality-dependent potentiation of COX-2 and PGE(2) production, and the osmolality-dependent inhibition of NO production and proteoglycan degradation in IL-1-activated cartilage. The data demonstrate that osmotic and cytokine signaling interact to differentially modulate IL-1-stimulated effects in calf articular cartilage.

Animals↗

PubMed2004

Robot-assisted pediatric surgery.

Computer-enhanced robotic surgical systems have been increasingly used to facilitate complex minimal access surgical procedures. In adult patients, such systems have been used to perform a wide variety of operations including coronary artery bypass grafting, mitral valve repair, Roux-en-Y gastric bypass, colon resection, nephrectomy, and radical prostatectomy. In the field of pediatric surgery, the experience with robotic surgical systems has been more limited. However, with improvements in robotic technology, interest and experience with robotic pediatric surgery have grown rapidly. The purpose of this article is to review the current experimental and clinical literature regarding the use of robotic surgical systems in the pediatric patient population.

Adult↗

PubMed2003

Surgical robotic applications in otolaryngology.

OBJECTIVES: To explore the feasibility of performing endo-robotic neck surgery in a porcine model and to compare the results of robotically enhanced endoscopic surgery with those from a conventional endoscopic technique. STUDY DESIGN: Prospective, nonrandomized experimental investigation in a porcine model. METHODS: We performed a consecutive series of endoscopic neck surgeries using the daVinci surgical system (Intuitive Surgical Inc.). The length of time required to establish the operative pocket and to assemble the robotic components, as well as the total duration of each operation, was recorded. The animals were continuously monitored for heart rate, blood pressure, and end-tidal CO(2) pressure, and evaluation for presence of pneumothorax and subcutaneous emphysema was undertaken postoperatively. The specimens were examined histologically. RESULTS: Four different types of neck surgery were successfully performed on both sides of the neck of four animals using the daVinci surgical system. Creation of the operative pocket took, on average (+/-SD), 18.1 +/- 11.9 minutes, and assembly of the robot required 12.5 +/- 9.9 minutes, resulting in a mean preparation time for all procedures of 30.6 +/- 21.0 minutes. The mean operative time for submandibular resection (n = 3) was 19.0 +/- 6.6 minutes, with a total procedure time of 39.0 +/- 10.2 minutes. Selective neck dissections (n = 3) required a mean operative time of 66.0 +/- 18.5 minutes and a total procedure time of 85.7 +/- 16.7 minutes. One partial parotidectomy and one thymectomy were also performed. The median estimated blood loss was 0 mL (range, 0-10 mL). The end-tidal CO(2) pressure fell from the start to the end of the procedures by a mean of 4.4 +/- 7.9 mm Hg. The blood pressure fell by a mean of 1.9 +/- 7.5 mm Hg. There was one case of modest subcutaneous emphysema, and there were no cases of pneumothorax or air embolism. No conversions to open resection were necessary. CONCLUSIONS: Robotically enhanced endoscopic surgery in the neck is feasible and offers a number of compelling advantages over conventional endoscopic neck surgery. Clinical trials will be necessary to determine whether these advantages can be achieved in clinical practice.

Animals↗

PubMed2002

Robotic-assisted endoscopic thoracic aortic anastomosis in juvenile lambs.

BACKGROUND: Advances in robotic technology have enabled a wider range of applications for minimally invasive techniques in cardiac surgery, including mitral valve repair and coronary artery bypass grafting. With increased technical sophistication, robotic-assisted techniques can be developed for the endoscopic repair of certain congenital cardiac lesions. OBJECTIVE: The purpose of this study was to assess the feasibility of closed chest thoracic aortic anastomosis in a juvenile ovine model. METHODS: Lambs, aged 45 to 55 days, underwent surgery that was performed using the da Vinci robotic surgical system. Using 3 ports, the surgeon dissected the descending thoracic aorta and mobilized it free from attachments, using single-lung ventilation and CO2 insufflation. Snares were introduced through 2 stab wounds for aortic occlusion proximally and distally. In 4 lambs, the aorta was completely transected and reanastomosed using interrupted nitinol sutures. One lamb underwent longitudinal aortotomy, and patch aortoplasty was performed with the placement of a Gore-Tex patch. Snares were released and the animals were recovered once hemodynamically stable. Animals were sacrificed at 6 to 12 hours after surgery and the descending aorta was harvested. Burst-pressure testing was performed on the anastomoses. RESULTS: All 5 lambs survived the procedure with stabilization of hemodynamic parameters following surgery. The mean aortic clamp time was 47 +/- 17 minutes, and the anastomosis was completed in 26 +/- 5 minutes. The mean burst pressure was 163 +/- 9 mm Hg. CONCLUSIONS: Endoscopic thoracic aortic anastomosis can be performed safely and with adequate exposure in a juvenile large-animal model using computer-assisted surgical techniques. With further refinements, these approaches could be applied to the repair of congenital anomalies of the aorta, including interrupted aortic arch and aortic coarctation.

Anastomosis, Surgical↗