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Arthur D Smith

Publications and source records attributed to Arthur D Smith.

35 records · Page 2Linked to original sources
PubMed2003

Immune response to laparoscopic bowel injury.

BACKGROUND AND PURPOSE: Laparoscopic bowel injuries are rare but potentially fatal if recognition is delayed. Unlike the situation after open surgery, patients with unrecognized bowel injury after laparoscopy do not present with the typical "acute surgical abdomen." We investigated monocyte, neutrophil, and lymphocyte apoptosis as indicators of the immune response and whether this response is stimulated or suppressed by laparoscopic bowel injury compared with bowel injury induced during open surgery. MATERIALS AND METHODS: After an animal protocol was approved, laparoscopy was performed in a rabbit model. A total of 44 animals were divided into four groups of 11 rabbits each. Laparoscopic bowel injury was created using 30-W electrocautery at 0 (control), 1, and 5 hours after induction of pneumoperitoneum. Bowel injury was created in the fourth group during open laparotomy. Animals were euthanized at 0, 1 day, 1 week, or 2 weeks after surgery. Apoptosis was assessed by staining the nuclei of blood cells with H-33342 dye. RESULTS: At 1 week, neutrophil, monocyte, and lymphocyte apoptosis levels were 2.4- to 5-fold lower after laparoscopy (1-hour pneumoperitoneum) compared with open surgery. However, at 2 weeks, the percentage of apoptosis had equalized in the two groups. Interestingly, with longer laparoscopic procedures (5 hours), the percentage of apoptosis at 0 and 1 day more closely approached that seen after open surgery. At 2 weeks, there was a significant difference in apoptosis levels in all cell types between the experimental groups compared with controls (P < 0.001). No animals undergoing a 5-hour open procedure survived to 2 weeks after bowel injury. CONCLUSIONS: Open surgery resulted in a significant increase in programmed cell death compared with controls in the immediate postoperative period following bowel injury. Laparoscopic surgery produced a delayed response and after 2 weeks with bowel perforation approached open surgery levels. The difference in the degree of cellular death may be secondary to a smaller degree of stimulation of the immune response in laparoscopic surgery.

Analysis of Variance↗
PubMed2003

Efficacy and morbidity of therapeutic renal embolization in the spectrum of urologic disease.

PURPOSE: We report the largest series of renal embolizations performed for a variety of indications. PATIENTS AND METHODS: A retrospective analysis was performed on embolizations performed in our institution from 1997 to 2002 encompassing 36 patients who underwent 44 procedures. RESULTS: Embolization was successful on the first attempt in 87% of the patients. A second embolization was performed in four of the five unsuccessful cases, three successfully, increasing the success rate to 95%. The mean postoperative narcotic use was 27.2 mg of morphine equivalent, and 10 mg or less was required by 45% of the patients. In the 14 patients who had not also undergone a surgical procedure, the mean narcotic use was 21 mg, and 64% required 10 mg or less. Only 15% of the patients developed fever, which resolved within 2 days in all cases. Leukocytosis was seen in 47%. Follow-up creatinine and hypertension information was available in 16 and 18 patients, respectively. After a mean follow-up of 269 days, only one patient had a clinically significant rise in the creatinine concentration. After a mean follow-up of 496 days, two patients had new-onset hypertension. There was no statistically significant difference in the success rate, narcotic use, complications, creatinine concentrations, or the likelihood of fever, leukocytosis, or hypertension according to the indication for embolization or the agent used. Use of a microcatheter was associated with less parenchymal loss, and decreased parenchymal loss was associated with a significant reduction of narcotic use. CONCLUSIONS: Renal embolization is a highly effective and well-tolerated procedure in a variety of urologic conditions. The indications and material used did not have a significant effect on the outcome. Reducing parenchymal loss can significantly reduce morbidity.

Analgesics↗
PubMed2003

Residual air persists in the renal collecting system following percutaneous nephrolithotomy.

OBJECTIVES: To determine the presence or absence of air in the renal collecting system 48 hours following percutaneous nephrolithotomy (PCNL). METHODS: The study was based on a review of the records of the last 100 consecutive patients undergoing PCNL for stone extraction. Two urologists and a uroradiologist reviewed post-PCNL nephrostogram films and determined the presence or absence of air in the urinary tract. RESULTS: Nephrostography was routinely performed 48 hours after PCNL, and all films of the 100 patients were reviewed. Gas was detected in 98 (98%) of the 100 cases that appeared as gas pyelograms outlining the renal calyces. Of the 98 cases, 33 (34%) demonstrated gas in the upper calyx, 10 (10%) in the middle calyx, 12 (13%) in the lower calyx, and 43 (44%) in more than one calyx. Gas was not detected in the renal parenchyma or perirenal areas. CONCLUSIONS: Gas is present within the renal collecting system 48 hours after a percutaneous procedure. Prospective studies should be performed to document the amount of time needed for complete resolution of gas from the collecting system.

Adult↗
PubMed2003

Optimal lesion assessment following acute radio frequency ablation of porcine kidney: cellular viability or histopathology?

PURPOSE: Radio frequency ablation (RFA) has been used as a minimally invasive alternative to nephrectomy for small renal tumors. Questions have arisen regarding the accuracy of cell viability determination on standard hematoxylin and eosin (H & E) staining. We investigated and compared the histological characteristics of RF ablated renal tissue using nicotinamide adenine dinucleotide (NADH) and H & E staining. MATERIALS AND METHODS: Ten porcine kidneys underwent laparoscopic RFA of the upper and lower poles using a 2 (8) or 3 cm (2) protocol with 2 cycles of 90 W, target temperature 105C and treatment time 5.5 minutes per cycle. Following tract ablation the kidneys were immediately harvested, gross lesion size was measured and tissue was processed for standard H & E and NADH staining. RESULTS: H & E staining of ablated tissue revealed a number of alterations in renal tubular histology. However, all of these findings were focal with areas of parenchyma that appeared well preserved. Corresponding areas on NADH processed sections showed the complete absence of staining, indicating the lack of cellular viability. There were no skip areas noted on NADH processed sections and treated portions demonstrated a well demarcated border of ablation. CONCLUSIONS: While RFA produces discernible histological changes acutely on H & E, these alterations are variable and patchy, and they alternate with areas of well preserved tissue. Therefore, NADH staining should always be used to assess and verify cellular death in RFA lesions. In this study no skip areas of viable cells were noted within areas of ablated tissue on NADH staining.

Animals↗
PubMed2002

Tail stent versus re-entry tube: a randomized comparison after percutaneous stone extraction.

OBJECTIVES: To evaluate the efficacy of a 7F tail stent with an 18F Councill nephrostomy tube and compare it to a 24F re-entry Malecot nephrostomy tube after percutaneous nephrolithotomy. METHODS: Forty patients were prospectively randomized to receive either a 24F re-entry Malecot nephrostomy tube (group A, n = 20) or a 7F tail stent with an 18F Councill nephrostomy tube (group B, n = 20) for postoperative drainage. Patients were evaluated with an analogue scale questionnaire 15 days after percutaneous nephrolithotomy at the routine office follow-up visit asking them to rate the flank pain on a 0 to 10 scale, urinary urgency on a 0 to 10 scale, and quality of life, while the external drainage tubes were still in place. RESULTS: The mean length of stay was 4.5 and 3.5 days for groups A and B, respectively. Flank urine leakage was present in all patients in group A for a period of 6 to 12 hours, and no patient in group B had any significant flank drainage. A statistically significant reduction of flank pain in favor of group B was observed (P = 0.0002). We did not observe any statistically significant difference when evaluating the urgency (P = 0.1) and quality-of-life scores (P = 0.09) between the two groups, even though a trend was noted toward amelioration in favor of group B patients. CONCLUSIONS: The results of the present study suggest that the 7F tail stent is certainly better tolerated by the patients after percutaneous nephrolithotomy compared with the standard 24F re-entry Malecot nephrostomy tube.

Drainage↗
PubMed2002

Comparison of robotic versus laparoscopic skills: is there a difference in the learning curve?

OBJECTIVES: To evaluate the learning curve between robot-assisted and manual laparoscopic suturing, as well as to assess other skills. Laparoscopic reconstructive procedures have been limited by instrumentation, small working spaces, and fixed angles at the trocar level to place sutures. Robot-assisted laparoscopic suture placement may provide one means of increasing dexterity and facilitating laparoscopic reconstructive procedures. METHODS: Eight physicians participated in this study. A series of five trials were performed to assess dexterity (task 1) and free-hand suturing (task 2). Each task was performed using robot-assisted and manual laparoscopy. The participants were categorized as novice and experienced laparoscopists. Task 1 involved passing sutures through the eye of seven needles positioned 1 cm apart in a P configuration. Task 2 involved tying one surgeon's knot, followed by two subsequent knots. RESULTS: The average time for trials 1 and 5 of task 1, robot-assisted laparoscopy, was 242.6 and 101.8 seconds, respectively (P <0.001). Both groups demonstrated a statistically significant difference (P <0.001) between the first and last trial. The average time for trials 1 and 5 of task 1, manual laparoscopy, was 205.3 and 169 seconds, respectively. The differences in the learning curves for robot-assisted and manual laparoscopy were statistically significant in favor of robotic assistance. Manual laparoscopic suturing did not demonstrate as much of a difference for the experienced surgeon. Overall, the difference in improvement between robot-assisted and manual laparoscopy was not statistically significant. CONCLUSIONS: Robot-assisted laparoscopic allows suturing and dexterity skills to be performed quicker than does manual laparoscopy.

Clinical Competence↗
PubMed2002

Role of acellular collagen matrix surgisis in the endoscopic management of ureteropelvic junction obstruction.

PURPOSE: To investigate the role of acellular collagen matrix (Surgisis during endopyelotomy. MATERIALS AND METHODS: Nine female pigs (25-35 kg) were enrolled in our protocol. The pigs were categorized as follows. Group I (N = 3) had endopyelotomy + insertion of SIS, Group II (N = 3) creation of UPJ stricture + endopyelotomy + insertion of SIS, and Group III (N = 3) Davis intubated ureterotomy using SIS. The contralateral side served as a control for each group (one pig in each group). In three pigs (two in Group III and one in Group II), Surgisis was treated with India ink prior to insertion at the endopyelotomy site. An endopyelotomy stent (14/8 F x 24 cm) was used to stent the ureteropelvic junction (UPJ) for 4 weeks. Four weeks after the stent was removed, laparoscopic nephroureterectomy was performed, and the animals were euthanized. Histopathologic analysis of the Surgisis-regenerated segment of the UPJ was performed using hematoxylin and eosin, reticular (collagen), smooth muscle actin, and S-100 (nerve) stains. RESULTS: All animals tolerated the procedure. The mean operative time was 162 minutes. One pig (Group II) developed pyonephrosis; one pig (Group III) developed significant ascites and was sacrificed 2 week before the end of the experiment. Histopathologic analysis showed complete epithelializaton at 8 weeks. Reticular stain demonstrated abundant collagen matrix in the submucosa. Smooth muscle staining revealed myofibroblastic proliferation within the SIS-regenerated tissue adjacent to disorganized smooth muscle cells. India ink-stained SIS-regenerated tissue did not show smooth muscle cells. The S-100 stain did not demonstrate neurons at 8 weeks; however, in three pigs, peristaltic activity was noted across the UPJ. CONCLUSION: The use of acellular collagen matrix in the endoscopic management of UPJ obstruction is a promising technique. The abundance of myofibroblasts and absence of abundant smooth muscle regeneration indicates a need to investigate the role of growth factors in SIS regeneration of host tissue.

Actins↗
PubMed2002

Tubular cell-Escherichia coli interaction products modulate migration of monocytes through generation of transforming growth factor-beta and macrophage-monocyte chemoattractant protein-1.

BACKGROUND: Urinary tract infection is a common occurrence often associated with renal interstitial inflammation in the form of accumulation of mononuclear cells. We hypothesized that bacteria activate tubular cells to secrete cytokines, which may promote migration of mononuclear cells at the site of interaction. MATERIALS AND METHODS: We evaluated the migration of monocytes in response to tubular cell products (TC-S) and interaction products of E. coli with proximal tubular cells (TC-EC-S; concentrations of 5%, 10%, and 25%) using a modified Boyden chamber. To determine the molecular mechanism, we evaluated the effect of antibodies against macrophage-monocyte chemoattractant protein-1 (MCP-1) and transforming growth factor-beta (TGF-beta) on E. coli-tubular cell interaction product-induced migration of monocytes. In addition, we studied the effect of free-radical scavengers on activation of tubular cells. RESULTS: The TC-EC-S enhanced (p < 0.0001) migration of monocytes compared with TC-S. Both anti-TGF-beta and anti-MCP-1 antibodies partly inhibited (p < 0.0001) TC-EC-S-induced monocyte migration. The modified TC-EC-S (produced in the presence of superoxide dismutase [SOD], dimethyl thiourea [DMTU], or catalase, all scavengers of free radicals) induced lesser monocyte migration than did TC-EC-S alone. CONCLUSIONS: These results suggest that E. coli activates tubular cells to generate cytokines such as MCP-1 and TGF-beta that promote migration of monocytes. Free radicals such as superoxide and hydrogen peroxide may be acting as second messengers in E. coli-induced tubular cell activation.

Antibodies↗
PubMed2002

Morphine-induced macrophage apoptosis modulates migration of macrophages: use of in vitro model of urinary tract infection.

BACKGROUND: Morphine has been reported to alter immune function. Morphine-induced macrophage apoptosis has been shown to contribute to altered immune status in an opiate milieu. We studied the effect of morphine-induced macrophage apoptosis on the migration of macrophages. Because urinary tract infection (UTI) is one of the commonest infections to evoke an inflammatory response; i.e., migration of neutrophils and monocytes to the site of infection, we used an in vitro model of UTI to test our hypothesis. MATERIALS AND METHODS: We carried out both in vivo and in vitro studies. Mice of the FVB/N strain were treated with morphine for short (three doses, 24 hours) and long (11 doses, 96 hours) durations, and their bone marrow cells were isolated. In addition, apoptotic macrophages were prepared by heat treatment. To simulate the in vitro model of UTI, E. coli-activated tubular cell (TC)-conditioned medium containing transforming growth factor-beta (TGF-beta) and macrophage-monocyte chemoattractant protein-1 (MCP-1) was used to test migration of macrophages across a filter in a modified Boyden chamber. In addition, migration of macrophages into the peritoneal cavity was evaluated in both control and morphine-treated states. The effect of morphine on apoptosis as well as migration was studied in murine macrophages and bone marrow cells. RESULTS: Morphine not only promoted apoptosis of bone marrow cells (20% apoptotic cells) but also inhibited their migration across the filter. Control cells showed minimal apoptosis but displayed greater migration. Similarly, heat-treated (apoptotic) cells showed minimal migration. In peritoneal macrophage studies, morphine treatment retarded migration. CONCLUSION: Morphine inhibits macrophage migration both in vivo and in vitro. This attenuated transmigration of macrophages seems to be secondary to the apoptotic effect of morphine.

Animals↗
PubMed2002

Reconstruction of rabbit urethra with surgisis small intestinal submucosa.

PURPOSE: To evaluate the efficacy of Surgisis, porcine small intestinal submucosa, in the reconstruction of iatrogenic urethral defects in rabbits. MATERIALS AND METHODS: Eight male white rabbits were enrolled in this protocol. A 2.5-cm segment of urethra was excised. One control consisted of a normal urethra. The other rabbits underwent urethroplasty with Surgisis and 6-0 Vicryl running suture. An 8F feeding tube was left in place to divert urine for 2 weeks after surgery. Retrograde urethrograms were performed to assess the patency of the urethras and to rule out fistula formation prior to sacrifice of the animals. The sacrifice protocol began with the control and a urethroplasty animal 6 weeks after surgery. The other rabbits were euthanized at 2-week intervals thereafter. RESULTS: Surgisis promoted epithelial regeneration in all cases. One animal developed a wound infection; this was associated with a small fistula at the proximal end of the anastomosis. Good cosmetic and functional results were documented. Retrograde urethrograms showed no stricture formation at the site of the anastomosis in six rabbits. The histopathologic examination showed complete regeneration of all urethral layers, almost indistinguishable from the normal urethra. CONCLUSION: Surgisis is an excellent material for urethral reconstruction in rabbits. It promotes regeneration of all the components of the host urethral layers and is biodegradable.

Animals↗
PubMed2002

Ureteral ischemia model: an explanation of ureteral dysfunction after chronic obstruction.

BACKGROUND AND PURPOSE: Many models of smooth muscle ischemia have been developed to explain organ insufficiency or failure. Ureteral decompensation may also be described in these terms. We anticipate that ureteral ischemia will result from overdistention brought about by obstruction. A preliminary model to create an ischemic ureter is described herein. MATERIALS AND METHODS: Six white New Zealand female rabbits were used for this study. All had their left ureters surgically ligated at the level of the urinary bladder. The right ureters served as controls. In the acute-phase group, the ureters were all reexplored 2 weeks postobstruction. Exploration of the other rabbits was delayed for 3 more weeks. A laser Doppler needle (Transonics Inc.) was used to measure tissue perfusion in the rental artery, renal vein, renal parenchyma, renal pelvis, ureteropelvic junction, upper ureter, mid ureter, lower ureter, and lateral wall of the bladder. Baseline and postobstructive measurements of tissue perfusion were collected and compared. RESULTS: In both the acute and the chronic obstruction groups, there was a demonstrable drop-off in perfusion of the ureteral sidewall. A more notable loss of perfusion was seen in the distal ureter. CONCLUSION: The increased wall tension in the obstructed ureter results in a significant decrease in smooth muscle perfusion. This ischemia may result in the same functional and histologic changes that occur in other smooth muscle organs. Ultimately, the poor outcomes of some restorative/reconstructive procedures on the ureter may be explained in terms of smooth muscle ischemia.

Animals↗
PubMed2002

Endoscopic management of renal lymphangioma: a case report.

A 46-year-old woman presented with total painless gross hematuria, an 8-mm polypoid mass that proved to be a lymphangioma was found in the upper pole collecting system of the left kidney. The mass was resected ureteroscopically with holmium laser fulguration of the base. The few reported cases of this rare lesion suggest that rigorous postoperative surveillance is not necessary for this benign condition.

Female↗
PubMed2002

The endourological management of complications associated with horseshoe kidney.

PURPOSE: Horseshoe kidneys are the most common renal fusion anomalies. Ureteropelvic junction obstruction, urolithiasis and renal malignancies are the most common complications that occur in this patient population. Endourological management of these complications has decreased perioperative morbidity. We identified the applications of minimally invasive surgery for treating complications secondary to horseshoe kidney. MATERIALS AND METHODS: A comprehensive literature review of the different endourological approaches in the management of complications secondary to horseshoe kidney was performed using MEDLINE. RESULTS: Ureteropelvic junction obstruction can be managed by percutaneous endopyelotomy or laparoscopic pyeloplasty with good results. Small stones associated with horseshoe kidney are best managed by shock wave lithotripsy, while stones that have failed management by shock wave lithotripsy or are greater than 2 cm. are best managed percutaneously. All patients should undergo metabolic evaluation. Ureteroscopy or shock wave lithotripsy is associated with a higher residual stone rate than the percutaneous approach. Laparoscopic nephrectomy is a safe and feasible option for benign and malignant horseshoe kidney diseases. CONCLUSIONS: Endourological techniques can be safe and effective for treating complications secondary to horseshoe kidney.

Humans↗
PubMedDate not supplied

Renal pelvic stones: choosing shock wave lithotripsy or percutaneous nephrolithotomy.

Introduction of minimally invasive techniques has revolutionized the surgical management of renal calculi. Extracorporeal shock wave lithotripsy and percutaneous nephrolithotomy are now both well-established procedures. Each modality has advantages and disadvantages, and the application of each should be based on well-defined factors. These variables include stone factors such as number, size, and composition; factors related to the stone's environment, including the stone's location, spatial anatomy of the renal collecting system, presence of hydronephrosis, and other anatomic variables, such as the presence of calyceal diverticula and renal anomalies; and clinical or patient factors like morbid obesity, the presence of a solitary kidney, and renal insufficiency. The morbidity of each procedure in relation to its efficacy should be taken in to account. This article will review current knowledge and suggest an algorithm for the rational management of renal calculi with shock wave lithotripsy and percutaneous nephrolithotomy.

Journal Article↗
PubMedDate not supplied

Hand-assisted laparoscopic renal surgery: current trends and applications.

OBJECTIVE: Hand-assisted laparoscopic surgery has recently been introduced in order to help ease the learning process associated with standard laparoscopic surgery. It has various urological applications in the management of malignant and benign disease of the kidney. The purpose of this study is to review the applications and the success rate associated with hand-assisted laparoscopic surgery. METHODS: A comprehensive literature review of hand-assisted urological surgery was performed using MEDLINE search. RESULTS: Hand-assisted laparoscopic nephrectomy has been performed for benign and malignant disease, donor renal transplant, and nephron sparing surgery with good success. Patients who undergo the hand-assisted procedure seem to have less perioperative morbidity than those who undergo an open procedure. This approach minimized the warm-ischemia time in renal transplantation. CONCLUSION: Hand-assisted nephrectomy is a useful tool facilitating the learning process in laparoscopy.

Carcinoma, Renal Cell↗
PubMedDate not supplied

Laparoscopic heminephrectomy for benign disease of the horseshoe kidney.

BACKGROUND AND OBJECTIVE: Minimally invasive surgery plays a definitive role in the management of complications associated with the horseshoe kidney (HK). Aberrant vessels, the renal isthmus, and renal ectopia are all unique features of this anomaly that make the laparoscopic approach a challenge. We report our experience with this technique in 2 patients. METHODS: Two patients with an HK were evaluated for recurrent urinary tract infection. In both cases, the nonfunctioning renal moiety was demonstrated by renal scan. A transperitoneal laparoscopic heminephrectomy was performed. The Endostapler device was used to divide the renal isthmus. RESULTS: The operative time was less than 3 hours. Blood loss was negligible. No intraoperative complications occurred. The hospital stay was 48 hours. Postoperative discomfort was minimal. CONCLUSION: Laparoscopic heminephrectomy is a safe and feasible approach for benign diseases of the HK. The Endostapler is a useful adjunct in the division of the renal isthmus.

Female↗