Comparative analysis of laparoscopic versus open splenectomy.

BACKGROUND: Laparoscopic splenectomy (LS) has been used to treat a variety of splenic disorders. However, there have been few direct comparisons of this approach with open splenectomy (OS). METHODS: Results and outcomes were compared retrospectively in 46 consecutive patients treated by laparoscopic (n = 26) or open splenectomy (n = 20) from January 1990 through March 1996. The two groups were similar in age, sex, and American Society of Anesthesiology classification. Splenectomy was performed for a variety of indications, and the majority of patients in both groups had normal or near-normal size spleens. All data are expressed as mean +/- standard deviation. RESULTS: Laparoscopic splenectomy was successfully completed in all 26 attempted cases. Operative times were significantly longer for LS (202 +/- 55 minutes) than for OS (134 +/- 43 minutes) (P < 0.001); however, operative times in the last 13 LS cases (176 +/- 48 minutes) averaged 51 minutes less than in the first 13 cases (227 +/- 51 minutes). Estimated operative blood loss was less for LS (222 +/- 280 mL) than for OS (376 +/- 500 mL) (P = not significant). A mean of 2.0 units of red blood cells was transfused in 4 (15%) of 26 patients during LS vs 1.0 unit transfused in 2 (10%) of 20 patients who had OS (P = NS). Patients who underwent LS required significantly less parenteral pain medications, had a more rapid return to regular diet, and were discharged sooner than patients who had OS. Complication rates were similar in the two groups. CONCLUSIONS: These results suggest that LS is technically safe and has several advantages over OS. Laparoscopic splenectomy should become the procedure of choice for the removal of normal and near-normal size spleens.

Comparison of diagnostic specimens and methods to evaluate infected venous access ports.

BACKGROUND: Implanted venous access port infection can be difficult to diagnose and treat. If device removal is necessary, confirming port infection is problematic. MATERIALS AND METHODS: Culture specimens from three sites, catheter tip (Tip), port pocket, and the material within the reservoir (Inside), were sent from ports removed for potential infection. The results of these cultures were compared to preremoval peripheral and central blood cultures. RESULTS: Forty-five ports were removed for suspected infection. Confirmed port infection was defined as positive culture(s) from one or more experimental specimen(s). In 29 evaluable cases, the Inside specimens were completely predictive. Tip specimens were less accurate, even with a lower diagnostic threshold. In 7 of 19 confirmed infections, only the Inside culture was diagnostic. CONCLUSION: The most predictive culture specimen in a potentially infected port is the thrombotic material inside the reservoir.

Construction and expression in tumor cells of a recombinant vaccinia virus encoding human interleukin-1 beta.

BACKGROUND: Human interleukin-1 beta (hIL-1 beta) injected intratumorally has demonstrated growth inhibition of transplanted subcutaneous tumors in mice, regression of metastatic lesions, resistance to tumor rechallenge, and increased survival. Vaccinia virus (VV) can be genetically engineered to produce cytokines and may be an effective vector for gene therapy of cancer. This study was designed to (a) construct a VV expressing hIL-1 beta, (b) assess tumor cell infection in vitro with this construct, (c) measure hIL-1 beta production, and (d) assess the bioactivity of the secreted cytokine. METHODS: The hIL-1 beta gene was amplified from a plasmid clone using polymerase chain reaction (PCR) and then cloned into a homologous recombination (HR) and expression vector, which was used to insert the hIL-1 beta gene into the VV genome. Selection of the recombinant VV (vMJ601hIL-1 beta) was based on inactivation of viral TK and expression of beta-galactosidase. vMJ601hIL-1 beta infectivity and cytokine production was assessed by infecting tumor cell lines and analyzing culture supernatants for hIL-1 beta. Bioactivity of the hIL-1 beta produced was demonstrated using an IL-1 dependent T helper cell line. RESULTS: The hIL-1 beta gene was successfully cloned into the VV genome by HR, which was confirmed by PCR. vMJ601hIL-1 beta efficiently infected tumor cells, as shown by increased hIL-1 beta secretion (0 to > 500 ng/ml) and morphologic evidence of viral cytopathic effect. vMJ601hIL-1 beta-infected cells secreted large amounts of hIL-1 beta (mean 772 ng/10(6) cells/24 h). The secreted hIL-1 beta was bioactive (mean bioactivity 6.8 x 10(8) U/mg of hIL-1 beta). CONCLUSIONS: (a) hIL-1 beta can be cloned into VV, (b) vMJ601hIL-1 beta retains its infectivity, (c) a large amount of hIL-1 beta is secreted, and (d) the secreted hIL-1 beta is bioactive. Recombinant VV may allow in situ cytokine gene delivery and expression in established tumors.

Venographic surveillance of tunneled venous access devices in adult oncology patients.

BACKGROUND: Tunneled venous access devices (VADs) are often essential in the care of patients with advanced malignancies, but they carry an uncertain risk of thrombosis. METHODS: To determine the incidence of venoocclusion related to silicone VADs in a population of adult oncology patients, we prospectively studied 50 individuals with upper extremity venograms approximately 6 weeks after their VADs had been implanted. Twenty-one of these patients were reevaluated with venograms approximately 12 weeks after catheterization. In addition, venograms were performed on a separate group of 24 patients who needed catheterization of axillary-subclavian veins that had been catheterized in the past. RESULTS: The 6-week venograms in the prospective study showed partial venous obstruction in 15 patients (30%), whereas three (6%) had developed symptomatic total venoocclusion by this time. The 12-week venograms showed two additional complete occlusions. Venograms of 30 previously catheterized veins showed complete venoocclusion in nine (30%), although only two had a history of thrombosis. CONCLUSIONS: Our observations indicate that VADs frequently cause partial venoocclusion within the first 6 weeks of catheterization and that permanent venous damage from VADs is common, even without a history of VAD-related thrombosis.

In vitro and in vivo kinetics of recombinant vaccinia virus cancer-gene therapy.

BACKGROUND: Gene therapy of cancer is a promising therapeutic modality. Recombinant vaccinia viruses (RecVV), engineered to produce cytokines, may be effective in this area. This study's purpose was to investigate the kinetics of RecVV infection, measuring protein production and in vivo viral growth pattern. METHODS: RecVV were constructed by homologous recombination, encoding murine interleukin-2 (mIL-2). After tumor cell infection, mIL-2 production was measured in vitro. Tumor-bearing and naive hosts were inoculated with RecVV and wild type vaccinia. Livers, spleens, and (where applicable) tumors were sequentially harvested, and tissue viral levels were measured. RESULTS: Infected tumor cells made high levels of mIL-2 after infection with RecVV encoding for this cytokine. Naive mice were able to clear recombinant but not wild type VV from their livers and spleens by days 3 and 5, respectively. Tumor-bearing animals had persistent RecVV titers in the tumor tissue at day 8. CONCLUSIONS: RecVV can infect tumor cells, causing the production of a large amount of foreign protein but are attenuated relative to wild type virus in the murine host.

Retained Hickman catheter cuff as an infection source following allogeneic bone marrow transplant.

The case is presented of an infected, retained Hickman catheter cuff in a patient suffering from chronic graft-versus-host disease (GVHD) following allogeneic bone marrow transplantation. This infection seeded to a distant site causing systemic symptoms and requiring inpatient surgical and medical treatment. Although many physicians leave the dacron Hickman cuff in place when removing catheters, the presence of chronic skin changes associated with GVHD may predispose these patients to long-term infectious complications from this retained foreign body. We therefore advocate cuff removal at the time of catheter removal in all transplant patients.

Vascular access for therapeutic plasma exchange.

Adequate venous access is an essential component of therapeutic plasma exchange (TPEX). The simplest kind of venous access is venipuncture of antecubital veins, but this technique may be limited by venous size or scarring following the procedure, requiring the placement of a specialized vascular access device (VAD). VADs provide reliable central venous access and may remain in place for several weeks or months, depending on the VAD and the venous site chosen. Their use, however, is potentially limited by the risk of complications. We discuss indications for insertion, choice of catheter and access site, and complications of VAD placement for TPEX.

Endocrine surgical diseases of elderly patients.

The causes, evaluation, and preoperative and postoperative care of primary hyperparathyroidism and thyroid nodules in the elderly patient population have been described. Primary hyperparathyroidism is easily diagnosed and is almost always curable by surgery. Elderly patients with asymptomatic disease are candidates for nonoperative, expectant management. If they become symptomatic, surgery should be performed. Postoperative care of the elderly patient who has undergone parathyroid exploration is potentially complicated by the patient's other medical problems, including cardiac and pulmonary difficulties, variable severity of symptoms of hypocalcemia, and sensitivity to medications. Thyroid nodules in the elderly may present later than in younger patients and are more likely to contain malignant tissue. Tissue diagnosis preoperatively, usually by FNA testing, is mandatory. Anaplastic thyroid carcinoma and thyroid lymphoma are both treated nonoperatively. Thyroid surgery in the elderly is usually well tolerated, although other medical conditions, as mentioned above, may complicate postoperative care. Thyroid carcinoma in the elderly carries a worse prognosis than in younger patients and should always be treated with postoperative adjuvant (radioablative) therapy. Although this does not affect survival (from the thyroid cancer), it does extend the disease-free interval. As the number of elderly patients increases, the frequency with which these disorders are encountered will also rise. It is important to realize that almost all elderly patients can both tolerate and benefit from surgical correction of these two disorders, if appropriate preoperative evaluation is coupled with excellent intraoperative and postoperative care.

A persistent outbreak of measles despite appropriate prevention and control measures.

From January 4 to May 13, 1985, an outbreak of 137 cases of measles occurred in Montana and persisted for 12 generations of spread. A total of 114 cases occurred on the Blackfeet Indian reservation in northwest Montana. Of the 137 cases, 82 (59.9%) were in school-aged children (aged 5-19 years). Of the 114 cases on the reservation, 108 (94.7%) were classified as programmatically nonpreventable. A total of 64 (82.1%) of the 78 patients on the reservation who were born after 1956 and were above the recommended age at vaccination had a history of adequate measles vaccination. Additionally, an audit of immunization records at the schools in Browning, Montana, where most of the cases occurred, showed that 98.7% of students were appropriately vaccinated. A retrospective cohort study in the Browning schools failed to identify age at vaccination or time since vaccination as significant risk factors for vaccine failure. Overall vaccine efficacy was 96.9% (95% confidence interval = 89.5-98.2%). None of 80 Browning students who were vaccinated at less than 12 months of age and revaccinated at 15 months of age or older became infected. A case-control study showed a significant association between attendance at Browning basketball games and infection early in the outbreak. This outbreak suggests that measles transmission may persist in some settings despite appropriate implementation of the current measles elimination strategy.