Jerome A. Johnson

Laparoscopic skills enhancement

BACKGROUND Laparoscopy requires a unique subset of surgical skills that, for the inexperienced, can significantly delay the development of basic operative skills. We hypothesized that learning laparoscopic suturing and knot tying would improve laparoscopic skills. METHODS A laparoscopic training seminar for junior surgical residents was established to test this hypothesis. Emphasis was placed on laparoscopic knot tying and suturing. Skills were assessed at the beginning and the end of the course. RESULTS All residents showed significant improvement. Dominant and nondominant hand skills improved by 30.2% and 26.9%, respectively. Two-handed skills improved by 58.6% and 30.1%. Overall scores improved by 28.9%. CONCLUSIONS A structured laparoscopic skills course stressing knot tying and suturing is an effective way to develop dexterity and significantly improve the performance of laparoscopic tasks. These improvements can be accomplished in a cost-effective curriculum that should enhance the surgical education of residents and speed the acquisition of competent operative skills.

Outcome analysis of long-term survivors following pancreaticoduodenectomy☆☆☆

The long-term sequelae of pancreaticoduodenectomy are not completely understood. In the present study nutritional status, pancreatic function, and subjective quality-of-life parameters were evaluated in 45 patients who had previously undergone either pylorus-preserving pancreaticoduodenectomy (PPPD) or standard pancreaticoduodenectomy (SPD). Quality-of-life parameters, as measured by the Short Form-36 health survey, demonstrated no significant differences between the subgroups and normal control subjects in six of the eight domains for physical and mental health. Patients who had undergone SPD were noted to have significantly lower scores for general health and vitality than either age-matched control subjects or those who had undergone PPPD. No differences in nutritional parameters or indicators of pancreatic exocrine function between the two groups were identified. An elevated hemoglobin Alc value was seen in only one patient who was not diabetic preoperatively. Our data indicate that long-term survivors of pancreaticoduodenectomy generally feel as good as their normal counterparts, although SPD may result in some health satisfaction deficits. Nutritional status and pancreatic exocrine function are not improved in patients undergoing a pylorus-preserving procedure, and postoperative pancreatic endocrine dysfunction is unusual in both groups.

Dehydroepiandrosterone-sulfate inhibits pancreatic carcinoma cell proliferation in vitro and in vivo

BACKGROUND Dehydroepiandrosterone-sulfate (DHEA-S) is a potent inhibitor of glucose-6 phosphate dehydrogenase, the rate limiting enzyme of the hexose monophosphate shunt, a biochemical pathway that provides substrate for DNA synthesis in neoplastic tissue. DHEA-S has been shown to inhibit the growth of neoplasms arriving from human skin, lung, colon, and mammary tissue. This study evaluates the effect of DHEA-S on human pancreatic cancer cell lines in vitro and in vivo. METHODS In vitro, the human pancreatic adenocarcinoma cell lines MiaPaCa-2, Capan-1, Capan-2, CAV and Panc-1 were treated with concentrations of 1.9 mumol/L to 1000 mumol/L DHEA-S in 1% dimethylsulfoxide (DMSO) for 5 consecutive days. Cell proliferation was determined by a nonradioactive cell proliferation assay and compared with DMSO treated controls. In vivo testing was performed by inoculating two cell lines, MiaPaCa-2 and Panc-I, into the flank of 40 male nude athymic mice in four study groups. After 1 week of growth, 667 mg/kg DHEA-S in 1% DMSO or 0.2 ml 1% DMSO alone in the control group was administered by daily intraperitoneal injection. Body weight and tumor size was recorded weekly, and tumor weight was measured after 3 weeks of treatment. RESULTS In vitro cell proliferation was decreased in the five cell lines by 36% to 62% of controls (p < 0.001) at 500 mumol/L DHEA-S. In vivo, after 2 weeks, tumor size was only 76% (p < 0.008) and 67% (p < 0.005) of the controls. After 3 weeks of treatment, tumor size was 73% (p < 0.001) and 53% (p < 0.001) of controls, and tumor weight was decreased by 73% in MiaPaCa-2 (p < 0.001) and 66% in Panc-1 (p < 0.001). Radioimmunoassay measurements of DHEA-S and testosterone from DHEA-S treated mouse plasma showed a significant increase in circulating levels of these hormones. CONCLUSIONS DHEA-S achieves high serum levels after intraperitoneal injection without elevation of serum testosterone levels and produces no significant toxicity. Treatment with DHEA-S results in a significant reduction of proliferation of human pancreatic cancer cells in culture and when grown as subcutaneous tumors in athymic nude mice.

Demonstration and characterization of the hemoconcentrating effect of ascitic fluid that accumulates during hemorrhagic pancreatitis

Plasma volume deficit and hemoconcentration in hemorrhagic pancreatitis may be induced by vasoactive factors released by the inflamed pancreas. The ability of intraperitoneally injected pancreatic ascitic fluid (human and experimental) to produce hemoconcentration was examined in 210 female Sprague-Dawley rats (200–250 g) randomly assigned to five groups: 56 (control); 10 (5 cc dog plasma); 20 (5 cc normal saline); 10 (5 cc human pancreatic exudate (HPA)); 124 (5 cc ascites from dogs (10) with bile salt-trypsin pancreatitis (EPA)). Pancreatic exudate was passed through a 0.2-μm filter, injected, and after 2 hr tail vein hematocrits were determined and rats autopsied. Statistical significance was determined by Students unpaired t test. Control hematocrit (HCT) was 45.1 ± 0.55 (SEM), not different from plasma- or saline-treated animals. Rats receiving HPA had a mean HCT higher than that of controls (52.9 ± 0.0, P < 0.001). Ten subgroups receiving EPA had a mean HCT from 46.5 ± 0.6 to 52.2 ± 0.9, and 7 of the 10 demonstrated significant hemoconcentration. Active trypsin and osmolality of EPA were excluded as causative. Hemoconcentrating effect of EPA remained after freezing at −20°C for up to 7 months, heating at 56°C for 10 min, treatment with 10% trichloroacetic acid (TCA), and extraction with equal volumes of anydrous ether. Ultrafiltered (1000-dalton Amicon) TCA-treated EPA showed persistence of hemoconcentrating effect. A biologically active factor (likely a peptide with molecular weight below 1000 daltons in the pancreatic exudate may cause hemoconcentration, and may be responsible for continued plasma loss in acute pancreatitis.

Transmission of live laparoscopic surgery over the Internet2

BACKGROUND Video broadcasting of surgical procedures is an important tool for education, training, and consultation. Current video conferencing systems are expensive and time-consuming and require preplanning. Real-time Internet video is known for its poor quality and relies on the equipment and the speed of the connection. The Internet2, a new high-speed (up to 2,048 Mbps), large bandwidth data network presently connects more than 100 universities and corporations. We have successfully used the Internet2 to broadcast the first real-time, high-quality audio/video program from a live laparoscopic operation to distant points. METHODS Video output of the laparoscopic camera and audio from a wireless microphone were broadcast to distant sites using a proprietary, PC-based implementation of H.320 video conferencing over a TCP/IP network connected to the Internet2. The receiving sites participated in two-way, real-time video and audio communications and graded the quality of the signal they received. RESULTS On August 25, 1998, a laparoscopic Nissen fundoplication was transmitted to Internet2 stations in Colorado, Pennsylvania, and to an Internet station in New York. On September 28 and 29, 1998, we broadcast laparoscopic operations throughout both days to the Internet2 Fall Conference in San Francisco, California. Most recently, on February 24, 1999, we transmitted a laparoscopic Heller myotomy to the Abilene Network Launch Event in Washington, DC. CONCLUSIONS The Internet2 is currently able to provide the bandwidth needed for a turn-key video conferencing system with high-resolution, real-time transmission. The system could be used for a variety of teaching and educational programs for experienced surgeons, residents, and medical students.

Prediction of progressive disease in Zollinger-Ellison Syndrome-comparison of available preoperative tests.

Abstract Availability of alternative methods of treatment of the Zollinger-Ellison syndrome (ZES) has necessitated a reevaluation of that disease. To evaluate ability of preoperative tests to predict postoperative clinical course, serum samples (frozen since collection) obtained fasting and after calcium stimulation in 18 patients with documented ZES with at least 5 years of postoperative follow-up were reassayed, fractionated into molecular components by gel filtration through a 200 × 1-cm Sephadex G-50 superfine column, and quantitated by assay with an antibody with equimolar recognition of the major C-terminal peptides. Total gastrin immunoreactivity (IRG), response of serum gastrin to calcium stimulation (SIRG), or the combination of these two factors are the most frequent criteria for estimating postoperative course and magnitude of disease. These measurements were compared to the percentage of G-17 (G-17/IRG) by the methods of R. S. Galen and S. R. Gambino (Beyond Normality: The Predictive Value and Efficiency of Medical Diagnoses, New York: Wiley, 1975, pp. 10–14, 50–51) (Sensitivity, Specificity, Predictive value of positive and negative tests, Efficiency). Percentage G-17 > 20% of IRG is the most sensitive (100%) and specific (91%) method of evaluating extent of disease preoperatively in patients with ZES.

Neoplastic Disorders of the Pancreas

Primary neoplasms of the pancreas present with a wide variety of clinical syndromes and represent various tumors. The majority have extremely high mortalities, although prognosis is dependent on histopathological type. Early and accurate diagnosis improves survival, but is difficult. Pancreatic neoplasms may be classified as tumors of the exocrine pancreas, tumors of the endocrine pancreas, and atypical neoplasms, such as lymphomas, mesotheliomas, and sarcomas. Benign masses of the pancreas are common, especially when associated with pancreatitis, and the differentiation can be quite difficult. Traditionally, the diagnosis is based on histologic confirmation, but it is obviously advantageous to diagnose these lesions correctly prospectively or preoperatively. This chapter will focus on the relevant laboratory tests that are appropriate in the evaluation of individuals with the most common classes of pancreatic tumors.

Response of species of gastrin to calcium infusion in ZES

was subsequently confirmed at laparotomy and total gastrectomy performed. Samples were individually assayed for total gastrin immunoreactivity by a sensitive radioimmunoassay. Synthetic human gastrin (SHG) was monoiodinated by a modification of the method of Hunter and Greenwood [12] and purified on DEAE Sephadex by column chromatography to yield pure monoiodogastrin [2]. Bound and free hormones were separated by an anion exchange resin (IRP-58M, Rohm and Haas, Philadelphia) after a 72-hr incubation at 4°C. Synthetic human gastrin (SHG) was used as reference standard. One-milliliter aliquots of serum from each time period were applied to a 200