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J W Cook

Publications and source records attributed to J W Cook.

At least 19 recordsLinked to original sources

From Hippocrates to Palmaz-Schatz, the history of carotid surgery.

The extracranial carotid artery is the most common site for peripheral vascular procedures. Although the association of carotid disease and neurologic dysfunction was understood by the ancient Greeks, over 1700 years would pass before the relevant anatomy was described. In the 16th and 17th centuries, attempts at treatment of carotid injury and aneurysm by ligation were met with extremely high rates of stroke and death. It is not until the mid 20th century, with the introduction of carotid angiography and improved vascular surgical techniques, that the era of reconstructive carotid surgery begins. We present a synopsis of the history of carotid surgery from ancient times to present day.

Angioplasty↗

Patency and flow characteristics using stapled vascular anastomoses in dialysis grafts.

BACKGROUND: Improving patency of hemodialysis grafts is challenging. Vascular stapling creates nonpenetrating anastomoses, possibly decreasing intimal hyperplasia. We investigated patency and flow characteristics of stapled hemodialysis grafts. METHODS: Eighty-six grafts (41 stapled, 45 sewn) were placed in 84 patients (prospective, randomized). The groups had comparable demographics. RESULTS: Thirty-six grafts were functioning at the study endpoint. Complications in both groups were similar. The primary patency (stapled, 342 days versus sewn, 382 days; P = 0.67) and secondary patency (stapled, 513 days versus sewn, 507 days; P = 0.76) had no significant differences. Flow characteristics were similar between the groups. Thrombectomies per patient-year were 1.01 for stapled grafts and 1.12 for sewn grafts (not significant). Stapling decreased the average operating time by 4.5 minutes. CONCLUSIONS: Stapled and sewn anastomoses have similar primary and secondary patency and flow characteristics, with minimal operative time differences. Stapled anastomoses are safe but had no advantage over sewn anastomoses in this study.

Anastomosis, Surgical↗

The influence of patient strength, aerobic capacity and body composition upon outcomes after coronary artery bypass grafting.

BACKGROUND: Physical activity, physical fitness and body habitus of patients may be important predictors of outcomes after cardiac surgery. This study sought to quantify physical fitness and determine whether components of fitness enhance the prediction of outcomes in a group of patients undergoing coronary artery bypass grafting. METHODS: A group of 200 patients were evaluated prior to coronary artery bypass surgery. A Veterans Specific Activity Questionnaire (VSAQ) measured aerobic capacity. A grip dynamometer assessed strength. Skin-fold thickness was used to calculate percent body fat and lean body mass index. Patients were divided into low risk (0-2.5%) and high risk (>2.5%) groups based on the STS National Cardiac Surgery Database prediction of operative mortality. RESULTS: Patients with both a high percent body fat and a low VSAQ were at higher risk for at least one serious complication (p<0.05) and a longer postoperative length of stay (p<0.05). CONCLUSION: This study suggests: 1) An index of physical fitness can be obtained preoperatively in cardiac surgical patients; 2) This information aids in the prediction of operative risk.

Aged↗

Interleukin-10 attenuates proinflammatory cytokine production and improves survival in lethal pancreatitis.

Given that interleukin (IL)-10 (IL-10) serves as a potent down-regulator of specific proinflammatory cytokines we reasoned that its administration should improve outcome in situations in which the biological response to a severe inflammatory challenge is the critical determinant of survival. To test our hypothesis we administered IL-10 in the setting of lethal pancreatitis to determine its effect on proinflammatory cytokine production and survival. We divided Sprague-Dawley rats into three groups. Controls (Group 1, n = 5) received a sham laparotomy. We induced pancreatitis in Group 2 (n = 9) and Group 3 (n = 9) via laparotomy and intrapancreatic infiltration of one mL of 5 per cent sodium taurocholate. Group 2 was treated only with saline, whereas Group 3 was treated with 10,000 units of IL-10 (in saline) at 30 minutes, 3.5 hours, and 6.5 hours after induction of pancreatitis. Serial blood samples were obtained at 6.5 hours for measurement of amylase, IL-1, and IL-6. The Kaplan-Meier method, Wilcoxon test, and Student's t test were used for analysis. Seven-day survival was 100, 0, and 45 per cent in Groups 1, 2, and 3, respectively. Production of amylase, IL-1, and IL-6 was lower in the IL-10-treated group (Group 3) compared with the group treated with saline alone (Group 2, P < 0.05). We conclude that administration of IL-10 in the setting of otherwise 100 per cent lethal experimental pancreatitis significantly reduces production of amylase, IL-1, and IL-6 and improves survival.

Amylases↗

The effects of interleukin-10 in hemorrhagic shock.

BACKGROUND: Interleukin-10 (IL-10) counteracts the effects of the proinflammatory cytokines interleukin-1 (IL-1), interleukin-6 (IL-6), and tumor necrosis factor (TNF). Experimental data suggest that inhibition of these proinflammatory cytokines improves outcome in sepsis, endotoxemia, necrotizing pancreatitis, and other severe inflammatory states. We hypothesized that the administration of IL-10 would attenuate the release of proinflammatory cytokines after severe hemorrhagic shock. METHODS: To test our hypothesis, male Sprague-Dawley rats (N = 20) were divided into control and experimental groups. We induced hemorrhagic shock by removing a sufficient quantity of blood to maintain a mean arterial pressure of 50 mm Hg or less for 120 min. The animals were then resuscitated with shed blood and an equal volume of 0.9% saline. The experimental group received 10,000 units of IL-10 at the initiation of shock. Serum IL-1, IL-6, TNF, and lactate were measured at baseline, after 120 min of shock, and 60 min after resuscitation. The rats were followed for 72 h to calculate survival. RESULTS: Similar levels of hypoperfusion were obtained in both groups as demonstrated by lactate levels and amount of shed blood. The survival rate (70%) was the same in both groups. Serum levels of IL-1 and IL-6 were not significantly different between the two groups, although there was a trend toward IL-6 suppression. TNF, however, was significantly lower in the IL-10-treated group at the end of shock (Wilcoxon test, P < 0. 025). CONCLUSION: Administration of IL-10 suppresses the TNF surge observed after severe hemorrhagic shock.

Animals↗

Inhibition of needlestick-induced simulated viremia by local measures.

BACKGROUND: The possibility of confinement of simulated retrovirus to the inoculation site after needlestick injuries to enhance chances of local intervention and function of lymphaticovenous communications was investigated. METHODS: Using the canine model, technetium-99 m sulfur colloid particles were injected subcutaneously and into the vein and lymphatics. Blood and lymph were collected at a higher level from the femoral vein and the major lymphatic. Flow rates, particle arrival times, concentrations, and other variables were evaluated for 45 minutes by gamma counting. A tourniquet was used to slow dissemination after subcutaneous injection. RESULTS: After subcutaneous inoculation, particles arrived in the blood at 2.81 +/- 0.54 minutes and in the lymph at 6.0 +/- 1.47 minutes. Application of a tourniquet delayed appearance in the blood to 7.11 +/- 1.5 minutes and in the lymph to 40.0 +/- 5.1 minutes. Concentration of particles in lymph was 1,000 times higher than in the blood. Flux values were comparable in both pathways, but accumulation patterns were different. After intravenous injection, particles arrived in lymph at 25.4 +/- 6.44 minutes. After intralymphatic injection particles arrived in the blood within 4 seconds. CONCLUSIONS: There are functional lymphaticovenous communications at the peripheral level. The period between virus inoculation and blood and lymph invasion may be extended by application of a tourniquet; therefore, time could be gained for local intervention.

Animals↗

Management of inflammatory aneurysm of the infrarenal aorta using retroperitoneal exposure, open aneurysmorrhaphy and descending aorta-to-femoral artery bypass.

The authors present a technique consisting of retroperitoneal exposure, but not dissection of the inflammatory aneurysm, anastomosis of a bypass graft through a short thoracotomy to the lowermost thoracic aorta, carrying it down retroperitoneally to both femoral arteries and under brief occlusion of the descending thoracic aorta, opening of the aneurysm and intra-aneurysmal occlusion of the inflow and outflow to the aneurysm. An illustrative case is presented.

Anastomosis, Surgical↗

Axillary artery aneurysms.

Aneurysms of the axillary artery are rare but potentially dangerous lesions that threaten the upper extremity with vascular and neurologic compromise. Most can be treated effectively with surgical excision and vascular grafting. An illustrative case is presented. These aneurysms may arise as pseudoaneurysms secondary to trauma or iatrogenic complications, or as degenerative lesions often secondary to the chronic use of crutches. They may also arise as postobstructive lesions in patients with thoracic outlet syndrome. Signs and symptoms vary with the cause of the aneurysm and may include mass effects with brachial plexus compression and thromboembolic events involving the hands and fingers. Arteriography is the mainstay of diagnosis, and treatment should be considered in most of these lesions as soon as they become apparent to prevent limb loss or dysfunction.

Aneurysm↗

Efficacy of an enzyme-linked immunosorbent assay for detection of urinary tract immunoglobulins for diagnosis of urinary tract infections.

Results of the Uristat test (Shield Diagnostics Ltd.), a novel enzyme-linked immunosorbent assay (ELISA) for detection of urine antibodies to seven common bacterial pathogens, were compared with results of urine culture, urinalysis, and clinical history to determine the usefulness of Uristat in the diagnosis of urinary tract infections (UTIs). Midstream, catheterized, and indwelling catheter urine specimens sent to the laboratory for culture were included in the study. Quantitative cultures were performed on both 5% sheep blood agar and eosin-methylene blue agar. Uristat ELISAs were performed according to the manufacturer's instructions. By using a Bacillus subtilis bioassay technique, antibacterial activity was detected in the urine of 236 (22.2%) of 1,061 patients. Probable, possible, or asymptomatic UTIs were diagnosed for 258 (24.3%) of the 1,061 patients. Of those infections, 219 (84.9%) were caused by bacterial species whose antibodies were detectable by Uristat. Uristat's sensitivity and specificity were 76.7 and 56.0%, respectively. Uristat's predictive values of positive and negative results were 31.2 and 90.2%, respectively. Further development of the Uristat test is necessary before it can be of assistance in the diagnosis of UTIs.

Adolescent↗

"Half and half" woven and knitted Dacron grafts in the aortoiliac and aortofemoral positions: seven and one-half years follow-up.

One-hundred fifty-eight patients received specially manufactured aortoiliac or aortofemoral bifurcated grafts with one limb woven, the other knitted from Dacron. During an observation period ranging from 1,567 to 2,555 days (average 2,130 days) no statistically significant difference was found in either platelet adherence (30 patients studied) or in clinical patency. According to the results of the study, the type of graft (woven or knitted) did not seem to influence either platelet adherence or patency rate in the aortoiliac or aortofemoral positions.

Aged↗

Traumatic tears of the thoracic aorta: improved results using the Bio-Medicus pump.

Traumatic disruption of the descending thoracic aorta is a relatively rare but dramatic injury. Controversy remains regarding the use of shunts during operative repair. Discouraged by our results using the "no shunt" technique, we adopted the recently reported technique using the Bio-Medicus pump for left atrium-femoral artery bypass without heparin sodium. At Charlotte Memorial Hospital and Medical Center, 39 patients were treated for tears of the descending thoracic aorta between January 1979 and October 1988. Eight patients died before repair could be completed. Four patients underwent repair using femorofemoral bypass with 1 death and no instances of paraplegia. Fifteen patients had repair using the no-shunt technique with 4 deaths and three instances of paraplegia. Since January 1986, 12 patients have been treated using the Bio-Medicus heparinless pump with no deaths and no instances of paraplegia. We present our experience to confirm the reports of others regarding the efficacy of this technique. We believe it reduces the morbidity and mortality associated with this serious injury and aids in the hemodynamic management of the patient during aortic clamping.

Adult↗

Balloon valvuloplasty in calcified aortic stenosis: a cause for caution and alarm.

Balloon dilation by the percutaneous route has recently been recommended as an alternative to surgical intervention in the management of calcified aortic valvular stenosis. To investigate the validity of balloon valvuloplasty, this procedure was carried out in the operating room under direct vision in 30 patients just prior to excision and replacement of the ossified aortic valve. Changes induced by balloon dilation were evaluated by visual inspection as well as by geometric measurements. By visual observation, balloon valvuloplasty did not have a detectable impact on the valvular anatomy in about 19 of the patients and induced enlargement of the functional aortic orifice judged as "minimal" or "moderate" in only 11. In no patient was there a substantial increase in the functional orifice size. These findings were supported by geometrical measurements. Therefore, we believe that the virtues of this procedure have been grossly overstated by its proponents and that it should be offered only to patients who present a truly forbidding risk by standards of modern surgery.

Adult↗