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Steven R Potter

Publications and source records attributed to Steven R Potter.

6 recordsLinked to original sources
PubMed2006

Single-surgeon laparoscopic donor nephrectomy and renal transplantation.

OBJECTIVES: To demonstrate the feasibility of single-surgeon performance of laparoscopic donor nephrectomy and recipient living renal transplantation. METHODS: Fifteen consecutive donor-recipient pairs were performed from August 2003 and July 2004 by a single surgeon at one institution. Routine donor and recipient outcome measures were prospectively assessed. RESULTS: The mean donor height and weight was 66 in. and 151 lb, respectively. All donors underwent left nephrectomy. Renal arteries were paired in 3 (20%) of 15 donors. No donors underwent conversion or transfusion. No donor complications occurred. The mean operating room time, estimated blood loss, and hospital stay was 195 minutes, 200 mL, and 2 days, respectively. The mean recipient height and weight was 65 in. and 158 lb, respectively. The mean recipient age was 46 years (range 21 to 69). Of the 15 recipients, 3 (20%) had previously undergone transplantation. The mean operating room time, blood loss, and hospital stay for the recipients was 155 minutes, 100 mL, and 4.5 days, respectively. No recipient operative complications occurred. All allografts functioned immediately. The median recipient creatinine nadir was 1.1 mg/dL. Of the 15 recipients, 3 (20%) had postoperative complications during follow-up, including reintubation in 1, pneumonia in 1, and acute rejection in 1. The patient and graft survival rate were both 100%, and the mean serum creatinine was 1.16 mg/dL at a mean and median follow-up of 187 and 164 days (range 18 to 350), respectively. CONCLUSIONS: We report the first series evaluating the performance of single-surgeon laparoscopic donor nephrectomy and living renal transplantation. Single-surgeon performance of both laparoscopic donor nephrectomy and living renal transplantation is technically feasible and logistically straightforward. The donor and recipient outcomes are consistent with those reported in published reports.

Adult↗
PubMed2004

An approach for estimating soil carbon using the National Nutrient Loss Database.

Agricultural lands have the potential to contribute to greenhouse gas mitigation by sequestering organic carbon within the soil. Credible and consistent estimates will be necessary to design programs and policies to encourage management practices that increase carbon sequestration. Because a nationwide survey of soil carbon by the wide range of natural resources and management conditions of the United States is prohibitively expensive, a simulation modeling approach must be used. The National Nutrient Loss Database (NNLD) is a modeling and database system designed and built jointly by the USDA- Natural Resources Conservation Service (NRCS) and Texas A&M University to provide science-based inferences on environmental impacts from changes in agricultural management practices and programs at the regional and national level. Currently, the NNLD simulates 16 crops and covers approximately 1.35 x 10(8) ha. For estimating soil carbon sequestration, the database will be populated with approximately 1.5 x 10(6) field-level model runs using the EPIC (Environmental Policy Impact Calculator) model, which includes newly incorporated carbon equations consistent with those in the Century model. Each run will represent a unique situation defined by state, crop, climate, soil, irrigation type, conservation practice, tillage system, and nutrient management treatment (nutrient rate, application frequency, application timing, and manure category). Results are to be assigned to specific National Resource Inventory points (NRI) to simulate regional and national baselines. In this article we present the modeling approach and discuss the strengths and limitations.

Agriculture↗
PubMed2003

Urinary stone size: comparison of abdominal plain radiography and noncontrast CT measurements.

BACKGROUND AND PURPOSE: To compare urinary stone size as measured by abdominal plain radiography (AXR) with stone size as measured by noncontrast three-dimensional spiral CT in patients with acute renal colic. PATIENTS AND METHODS: Patients presenting to the emergency room of a single institution with urinary stones that were visible on both AXR and noncontrast spiral CT were identified. Two radiologists blinded to the clinical outcomes separately and randomly reviewed all films and measured maximum longitudinal (craniocaudal) and transverse (anteroposterior) stone diameters. The two-tailed paired Student's t-test was used to compare the sizes of each stone on AXR and CT. RESULTS: Over a 1-year period, 22 patients were identified with a total of 31 urinary stones visible on both AXR and CT. Nineteen stones were located in the kidney, three in the midureter, and nine in the distal ureter. The mean stone size by AXR was 6.1 mm (range 2-13 mm; SD +/- 1.95) in the longitudinal axis and 5.3 mm (range 2-11 mm; SD +/- 1.50) in the transverse axis. The mean stone size by CT was 6.9 mm (range 3-12 mm; SD +/- 1.95) in the longitudinal axis and 6.1 mm (range 2-11 mm; SD +/- 1.50) in the transverse. The differences between AXR and CT measurements did not attain significance in either the longitudinal (p = 0.67) or the transverse (p = 0.25) axis. CONCLUSIONS: A CT scan provides estimates of stone size that are consistently greater than those of AXR in both the longitudinal and transverse axes. However, for stones between 2 and 13 mm in maximum diameter, these differences do not attain significance. In patients with a history of radiopaque stones in this size range, therefore, AXR may provide useful size data for clinical decision-making without concern about significant disparities between the two modalities. As AXRs are more expeditiously obtained, incur less direct costs, and expose patients to significantly lower doses of radiation than CT scans, they remain a useful adjunctive study in the work-up of nephrolithiasis.

Adult↗
PubMed2002

Hand-assisted laparoscopic living-donor nephrectomy as an alternative to traditional laparoscopic living-donor nephrectomy.

The benefits of laparoscopic living-donor nephrectomy (LDN) are well described, while similar data on hand-assisted laparoscopic living-donor nephrectomy (HALDN) are lacking. We compare hand-assisted laparoscopic living-donor nephrectomy with open donor nephrectomy. One hundred consecutive hand-assisted laparoscopic living-donor nephrectomy (10/98-8/01) donor/recipient pairs were compared to 50 open donor nephrectomy pairs (8/97-1/00). Mean donor weights were similar (179.6 +/- 40.8 vs. 167.4 +/- 30.3 lb; p = NS), while donor age was greater among hand-assisted laparoscopic living-donor nephrectomy (38.2 +/- 9.5 vs. 31.2 +/- 7.8 year; p < 0.01). Right nephrectomies was fewer in hand-assisted laparoscopic living-donor nephrectomy [17/100 (17%) vs. 22/50 (44%); p < 0.05]. Operative time for hand-assisted laparoscopic living-donor nephrectomy (3.9 +/- 0.7 vs. 2.9 +/- 0.5 h; p < 0.01) was longer; however, return to diet (6.9 +/- 2.8 vs. 25.6 +/- 6.1 h; p < 0.01), narcotics requirement (17.9 +/- 6.3 vs. 56.3 +/- 6.4h; p < 0.01) and length of stay (51.7 +/- 22.2 vs. 129.6 +/- 65.7 h; p < 0.01) were less than open donor nephrectomy. Costs were similar ($11072 vs. 10840). Graft function and 1-week Cr of 1.4 +/- 0.9 vs. 1.6 +/- 1.1 g/dL (p = NS) were similar. With the introduction of HALDN, our laparoscopic living-donor nephrectomy program has increased by 20%. Thus, similar to traditional laparoscopic donor nephrectomy, hand-assisted laparoscopic living-donor nephrectomy provides advantages over open donor nephrectomy without increasing costs.

Activities of Daily Living↗