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BACKGROUND/PURPOSE: Telemedicine affords the opportunity to extend the presence of surgical evaluation to centers without an on-site pediatric surgeon. However, concern for cost, accuracy of diagnosis, and physician acceptance have limited its use. METHODS: Using a low-cost, desktop computer-based system, this study was designed to test the effectiveness of telemedicine in neonatal surgical consultation. RESULTS: Early experience with six video-teleconference (VTC) and six store-and-forward consultations are presented. Diagnosis was established accurately in all cases. With the three intestinal cases (jejunal atresia, duplication cyst, and r/o malrotation), diagnostic studies were guided by the images transmitted with the consult. Earlier care could be implemented in other cases. Technical problems were encountered primarily with the VTC modality, which also proved more consuming of physician time. CONCLUSIONS: Telemedicine was used successfully in each case and proved accurate in diagnosis and guiding further evaluation. This is the first report of the use of telemedicine for surgical consultation in the intensive care nursery.

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Although hirulog, a specific, direct inhibitor of thrombin, can prevent thrombosis in unstable angina and angioplasty without inducing excessive bleeding, it has not been used in a surgical setting. In the present study, the antithrombotic activity of hirulog was assessed in rats undergoing carotid endarterectomy. Three groups of anesthetized male Sprague-Dawley rats received either intravenous heparin (10 U/kg bolus followed by 90 U/kg/hr, n = 4), high-dose hirulog (0.8 mg/kg bolus followed by 2.2 mg/kg/hr, n = 7), or saline (n = 6) before endarterectomy and until termination of the protocol 30 min later. Platelet deposition, as measured by scanning electron microscopy, in rats receiving this high dose of hirulog was reduced by 63% (+/- 14%, SE) compared to controls (P = 0.004) and by 36% (+/- 16%) in heparinized rats (P - 0.07). Both groups had prolonged postsurgical bleeding. Infusion of hirulog at a lower dose (0.4 mg/kg bolus followed by 1.0 mg/kg/hr, n = 8) was not associated with prolonged bleeding; however, platelet deposition was reduced by only 16% (+/- 27%, P = 0.30), although 125I-fibrin deposition was reduced by 64% (+/- 11%, P = 0.004). In the high-dose hirulog group, plasma hirulog levels, as determined with a quantitative thrombin time, were three times higher (95% CI: 1.5-4.5 times) than in the group receiving the lower hirulog dose [11.6 +/- 2.3 (SE) micrograms/ml vs 3.9 +/- 0.6 micrograms/ml; P = 0.0022]. However, the mean activated partial thromboplastin time with the higher dose was similar to that of the lower dose (110 +/- 4 vs 90 +/- 13 sec, P - 0.09). The antithrombotic activity of hirulog can be maximized by titrating the dose, monitoring plasma drug levels, and possibly administering the drug after surgery to avoid prolonged bleeding.

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BACKGROUND: Purified human cross-linked hemoglobin, which is now being used in clinical trials, increases mean arterial pressure through binding of nitric oxide (NO). We postulated that binding of NO by cross-linked hemoglobin (alpha alpha Hb) could also increase platelet deposition at sites of subintimal injury. METHODS AND RESULTS: Male Sprague-Dawley rats were infused with alpha alpha Hb (0.88 g/kg, n = 8) or with the NO synthase inhibitor NG-monomethyl-L-arginine (L-NMMA, 30 mg/kg, n = 7) before undergoing microsurgical carotid endarterectomy. 111In-labeled platelets were infused after endarterectomy, and platelet deposition was measured 20 minutes later. In control endarterectomized rats (n = 8), mean platelet deposition was 7.7 +/- 0.7 x 10(6)/mm2. Platelet deposition was significantly increased above controls in rats that received alpha alpha Hb (13.2 +/- 0.9 x 10(6)/mm2, P = .0004) and in rats infused with L-NMMA (13.9 +/- 1.0 x 10(6)/mm2, P = .0002). The increase was prevented by infusion of L-arginine (150 mg/kg) immediately after alpha alpha Hb or L-NMMA. To determine whether aspirin (ASA) blocked the increased deposition induced by alpha alpha Hb, rats received oral ASA (10 mg/kg) 18 hours before endarterectomy. Platelet deposition in animals receiving ASA alone was 6.4 +/- 0.9 x 10(6)/mm2 (n = 8). This was significantly increased to 10.8 +/- 0.8 x 10(6)/mm2 (P = .002) for the ASA-treated group that received alpha alpha Hb at the time of endarterectomy (n = 8). The prolonged bleeding times induced by ASA were unaffected by the infusion of alpha alpha Hb. CONCLUSIONS: These data suggest that in a rat endarterectomy model, alpha alpha Hb increases platelet deposition at sites of subintimal injury by binding NO. Increased deposition induced by alpha alpha Hb can be prevented by administration of L-arginine but not by pretreatment with aspirin.

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Congenital deficiency of antithrombin III (AT III) is the only inherited hypercoagulable disorder for which a concentrate of purified protein is available for replacement therapy during periods of increased thrombotic risk. This report describes how such concentrates have been used in a patient with congenital AT-III deficiency undergoing venous surgery. A 40-year-old woman with AT III deficiency was evaluated for bilateral grade 3 chronic venous insufficiency. Noninvasive venous assessment and ascending venography revealed incompetence of the lower leg perforators, a patent deep venous system, and competent greater and lesser saphenous veins. Staged subfascial ligations were performed. Pasteurized AT III was administered 1 hour before surgery and at 30 hours at a dose calculated to increase AT-III activity to at least 120%. Perioperative AT III activity levels were measured. Subcutaneous heparin and oral warfarin were initiated the evening of surgery. An infusion of AT III increased plasma AT III from the baseline activity of 51% to 180%; it was 87% 13 hours later. Two measurements of the initial half-life of AT III were 7 and 14 hours. No perioperative thrombotic complications occurred. The ulcers healed, and the patient remains symptom free. Pasteurized AT III concentrates are now commercially available, easily administered, and provide a useful adjunct to the anticoagulation regimen of patients with AT III deficiency undergoing vascular surgery.

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A case of severe lymphedema of the lower extremity caused by obstruction by human immunodeficiency virus-associated Kaposi's sarcoma is presented. A review of the signs and symptoms of obstructive lymphedema and Kaposi's sarcoma is provided. Early recognition of this clinical entity may allow use of simple preventative measures and help to avoid this life- and limb-threatening situation.

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PURPOSE: Hirulog, a thrombin-specific inhibitor, has shown efficacy in reducing arterial thrombosis in patients treated with aspirin who require angioplasty or have unstable angina. In this study, the effect of hirulog on reducing deposition of indium 111-labeled platelets was assessed in a surgical model of aspirin-treated rats undergoing carotid endarterectomy. METHODS: Animals were randomly assigned to one of five groups: control (no aspirin or hirulog); aspirin alone (10 mg/kg); aspirin plus low-dose hirulog (0.2 mg/kg bolus followed by 0.5 mg/kg/hr); aspirin plus medium-dose hirulog (0.4 mg/kg bolus followed by 1.0 mg/kg/hr); or aspirin plus high-dose hirulog (0.6 mg/kg bolus followed by 1.5 mg/kg/hr). Hirulog was infused before surgery and continued until termination of the experiment 30 minutes after endarterectomy. RESULTS: Platelet deposition in rats receiving aspirin alone was reduced by 19% +/- 23% SE (p = 0.26) compared with controls. Deposition in aspirin-treated groups receiving low-, medium-, and high-dose hirulog decreased in a dose-dependent manner by 37% +/- 20% (p = 0.048), 44% +/- 19% (p = 0.061), and 56% +/- 13% (p = 0.022), respectively. As the dose of hirulog was increased, the plasma hirulog levels and activated partial thromboplastin time ratios (final:initial) also increased in a dose-dependent manner. The mean plasma hirulog levels ranged from 0.74 +/- 0.08 micrograms/ml in the low-dose hirulog group to 2.55 +/- 0.08 micrograms/ml in the high-dose hirulog group, and the corresponding activated partial thromboplastin time ratios were 1.5 +/- 0.12 (p = 0.001) and 3.3 +/- 0.63 (p = 0.001). Bleeding was easily controlled by local hemostatic measures for all experimental groups. CONCLUSION: Hirulog causes significant decrease in 111In-labeled platelet deposition in aspirin-treated rats subjected to microsurgical endarterectomy at doses that allow surgical hemostasis to be easily established.

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BACKGROUND: The efficacy of fibrinolytic therapy is limited by the small surface area of the clot that is available for the binding of the thrombolytic agent, such as tissue-type plasminogen activator (t-PA). We hypothesized that exposure of the clot to ultrasound during thrombolytic treatment could enhance lysis through perturbation of the thrombus, which would expose additional fibrin binding sites for t-PA. METHODS AND RESULTS: Whole human blood clots containing radiolabeled fibrinogen were incubated in vitro for 200 minutes with Tris-albumin buffer containing t-PA at concentrations ranging from 3 to 3,000 IU/ml. In paired experiments, one of the clots also was exposed to intermittent ultrasound (1 MHz, 1.75 W/cm2) throughout the experiment. The ultrasound was delivered as a 2-second exposure followed by a 2-second rest interval. The overall difference in mean clot lysis between thrombi receiving ultrasound and those receiving no ultrasound was significant (p less than 0.001) at all concentrations of t-PA. For clots incubated with t-PA at a concentration of 300 IU/ml, ultrasound increased the percent lysis at 200 minutes from 42 +/- 5% (mean +/- SEM) to 64 +/- 10%. In six paired experiments in a rabbit jugular vein thrombosis model, rabbits received 1 mg t-PA alone or t-PA and intermittent ultrasound (1 MHz, 1.75 W/cm2) for 200 minutes. For rabbits receiving ultrasound and t-PA, lysis was 55 +/- 11% at 100 minutes compared with 30 +/- 12% for rabbits receiving only t-PA. Lysis was 6 +/- 10% for rabbits (n = 4) receiving ultrasound alone. No evidence for tissue damage was noted in rabbits exposed to intermittent ultrasound. CONCLUSIONS: Exposure of whole blood clots in vitro to intermittent ultrasound combined with t-PA caused a significant enhancement of thrombolysis compared with t-PA alone. Intermittent ultrasound also showed a trend toward enhancement of t-PA-induced clot lysis in an animal thrombosis model. These data suggest that noninvasive intermittent ultrasound may be a useful adjunct to thrombolytic therapy.

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Clinical and phlebographic evidence exists that correlates the presence of varices of the vulva, posterior thigh, and the pelvic congestion syndrome with insufficiency of the internal iliac venous system (pelvic dumping syndrome). Information in the modern medical literature regarding the valvular anatomy of the internal iliac veins and its tributaries is limited. We dissected 82 iliac venous system specimens in 42 human cadavers (29 men, 13 women) to gain information on the relationship between the disease described and the anatomy of the region. Each specimen contained common, external, and internal iliac veins, including the tributaries of the latter. We recorded the anatomic variations of the internal iliac vein trunk and the location of valves in the complete iliac venous system, including 485 tributaries of the internal iliac veins. Five specimens of internal iliac vein had calcified thrombosis or were extensively involved with pelvic carcinoma and were not suitable for valve study, which left 79 specimens for analysis. The internal iliac vein drained into the external iliac venous system by means of a single trunk in 73% of the specimens and by two well-formed and separated trunks in 27% of the specimens. In one specimen (1.2%) the internal iliac vein drained directly into the inferior vena cava (parallel internal and external iliac veins). One specimen had a well-developed valve in the common iliac vein (1.2%). The external iliac vein had one valve in 26.2% of the specimens. This vein had three times as many valves on the right side as in the left (39.6% vs 14.6%: p = 0.0106).(ABSTRACT TRUNCATED AT 250 WORDS)

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Inflammatory aneurysms are an uncommon disorder that represent between 5% and 10% of abdominal aortic aneurysms. Their presentation is often variable and may include pain and obstruction of adjacent anatomic structures. This report describes a 68-year-old man who sought treatment after insidious onset of progressive bilateral lower extremity edema over a 6-month period. Noninvasive studies were suggestive of bilateral iliac vein occlusion, and a venogram showed a nearly obstructed vena cava from external compression. A CT scan showed a thick-walled infrarenal abdominal aneurysm. At exploration an inflammatory abdominal aortic aneurysm was found. Because of the presence of dense inflammatory changes surrounding the aneurysm and extending into the pelvis, the surgical procedure of choice was an aortobifemoral bypass graft done with Dacron. The aneurysmal wall was debrided from the vena cava. His postoperative course was uneventful, his edema resolved, and follow-up noninvasive studies were normal. Postoperative venography showed resolution of the extrinsic compression of the vena cava.

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Chronic lower-leg edema in patients with venous disorders was studied by means of lymphoscintigraphy. Lymphatic patterns of flow were evaluated prospectively in 26 patients with technetium 99m antimony trisulfide colloid injected subcutaneously in the interdigital web spaces on the feet. Most patients in this study had postphlebitic syndrome, and all of these patients had abnormal lymphoscintigraphic flow patterns. Nine had evidence of lymphatic obstruction, and one had an enhanced flow pattern. Three patients had veins used for distal arterial bypass, and all these veins showed decreased lymphatic flow. Two patients with Klippel-Trenaunay syndrome (congenital varicose veins associated with limb elongation, a capillary nevus, and an abnormal deep venous system) had obstruction to lymphatic flow, and two others had normal and enhanced patterns. Normal studies were seen in four of five patients who had veins used for coronary artery bypass grafting. The finding of decreased lymphatic flow in patients appears to be the result of the length of time from an episode of deep venous thrombosis, the occurrence and number of episodes of cellulitis and lymphangitis, and mobilization of the vein for use in distal arterial bypass surgery. This study shows that the edema attributed previously to primary venous disorders may have a significant lymphatic component. The degree of lymphatic obstruction can be determined by lymphoscintigraphy with technetium-labeled antimony trisulfide colloid.

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The incidence of coronary artery disease in patients coming to aortic surgery and the impact of aggressive preoperative cardiac catheterization and myocardial revascularization was prospectively analyzed in 59 patients. Seventy-five percent of patients had at least one-vessel involvement, and 32% had three-vessel or left main involvement. Patients with electrocardiographic evidence of coronary artery disease had at least one-vessel involvement 84% of the time and three-vessel, left main involvement 36% of the time. Sixty-four percent of patients with no preoperative indications of coronary artery disease had at least one-vessel involvement and 29% had three-vessel, left main involvement. Resting (39 patients) and exercise multiple-gated acquisition scans (22 patients) did not predict the presence of coronary artery disease in patients without a history or electrocardiographic evidence of coronary artery disease. Myocardial revascularization was performed prior to aortic surgery in 17 patients (29%). The operative mortality was 3.7% with two patients dying from noncardiac-related complications. There were two additional deaths prior to aortic surgery with one patient dying during coronary artery bypass grafting, and one dying of aneurysm rupture prior to repair, making the overall mortality associated with this approach 7.4%. Preoperative cardiac catheterization and an aggressive approach toward coronary artery bypass grafting reduces the risk of cardiac complications in aortic surgery.

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Wound hematomas, following carotid endarterectomy, are uncommon but potentially lethal complications. The management of 13 patients with this condition is presented. Factors that appeared to predispose to hematoma formation included perioperative use of platelet inhibitory drugs and postoperative hypertension. When the diagnosis of neck wound hematoma is made after carotid endarterectomy, prompt evacuation under local anesthesia is recommended.

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Fifteen of 596 (2.5 percent) carotid endarterectomies performed at Brooke Army Medical Center were complicated by significant wound hematomas requiring reoperation and hematoma evacuation. The wound hematomas resulted from capillary oozing in 80 percent of the cases and arteriotomy bleeders in 20 percent of the cases. Antiplatelet therapy and postoperative hypertension appear to be significant factors predisposing to the development of wound hematomas. In eight cases, local anesthesia was utilized for the hematoma evacuation, and there were no complications. When general anesthesia was utilized for hematoma evacuation, there was considerable difficulty with airway management in six of seven patients. Complications developed in four of these patients. One patient had respiratory insufficiency secondary to laryngeal edema. Two of the patients sustained myocardial infarctions, one of whom died, and a dense neurologic deficit developed in the fourth patient who died as a result of this complication. Meticulous surgical technique in obtaining hemostasis, control of postoperative hypertension, and wound drainage when indicated will help reduce the incidence of postoperative wound hematoma. When a significant postoperative wound hematoma does complicate carotid endarterectomy, the hematoma should be promptly evacuated utilizing local anesthesia.

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Colostomy perforation is an infrequent but often disastrous and lethal complication. In the majority of patients, the traumatic perforation occurs during irrigation through the colostomy stoma. This case report reviews the clinical course of a patient with a subcutaneous colostomy perforation and the subsequent development of an extensive abscess. Aspects of the management included mobilization of the colostomy and thorough surgical debridement and drainage. In addition, the report introduces the use of the new semisynthetic biologic dressing, BioBrane. This synthetic, semipermeable skin substitute served as a temporary dressing, provided good stability, and supported the application of a stoma appliance.

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A method for quantitating the specific stimulation of peripheral lymphocytes has been developed using the techniques of flow microfluorometry. Peripheral bovine lymphocytes were collected and specifically stained for deoxyribonucleic acid (DNA) content using a low-salt propidium iodide procedure. Flow microfluorometry was used to determine, on the basis of DNA content, the percentage of cells in a population that was stimulated. Extremely uniform staining of the lymphocytes (coefficient of variation of less than 2%) provides a high resolution between proliferating and nonproliferating cells. The method provides a rapid, highly repoducible technique for determing the fraction of lymphocytes stimulated in response to tuberculin antigens based on an increase in cellular DNA content. Specific and nonspecific stimulation by a defined antigen can be measured and resolved.

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