Biomedical subjects

J Eugene

Publications and source records attributed to J Eugene.

At least 19 recordsLinked to original sources

PubMed2001

Reoperative coronary bypass surgery using normothermic cardiopulmonary bypass: comparison with first-time procedures.

Redo coronary artery bypass grafting (CABG) is characterized by increased patient risk compared with first-time CABG. The reason for higher risk is not completely understood but it is logically related to inadequate myocardial preservation evidenced by the higher incidence of postoperative low-output syndrome. We compared normothermic cardiopulmonary bypass with cold blood maintenance cardioplegia in both first-time and redo CABGs to determine whether this single approach is appropriate for both instances. Five hundred seventeen consecutive CABG patients were retrospectively reviewed. Four hundred fifty-four first-time CABG procedures were compared with 44 redo procedures. All aspects of the operation were identical including myocardial preservation. Retrospective univariant analysis of both groups followed. Three clinical features distinguished first-time versus redo CABG. These were previous percutaneous transluminal coronary angioplasty (first-time 19% vs redo 71%; P < 0.001), preoperative intra-aortic balloon pump (first-time 38% vs redo 71%; P < 0.001), and Parsonnet risk score (first-time 11.7+/-8.2 vs redo 19.2+/-8.8; P < 0.001). Operative mortality for redo CABG was higher than in first-time procedures (3.4% vs 6.4%; P = not significant), although small sample size limited statistical significance. The length of stay was statistically longer in redo patients (8.7+/-10.8 vs 6.0+/-5.1 days; P < 0.01) and is related to a higher Parsonnet score, increased postoperative pneumonia, and failed percutaneous transluminal coronary angioplasty before redo CABG. We conclude that redo CABG is a different operation from first-time procedures and requires enhanced myocardial preservation. Normothermic cardiopulmonary bypass with cold blood maintenance cardioplegia does not appear to achieve this goal.

Aged↗

PubMed1997

Reduction pneumonoplasty for patients with a forced expiratory volume in 1 second of 500 milliliters or less.

BACKGROUND: Patients with severely impaired pulmonary function are considered at high risk for emphysema operations. We prospectively evaluated 44 patients with a forced expiratory volume in 1 second of 0.5 L or less undergoing reduction pneumonoplasty for dyspnea uncontrolled by medical management (confirmed by Borg and modified Medical Research Council dyspnea scales). METHODS: There were 28 men and 16 women (mean age, 66 years) with a mean preoperative forced expiratory volume in 1 second of 0.41 L (range, 0.23 L to 0.50 L). Preoperative therapy consisted of bronchodilators (100% of patients), oxygen (80%), and steroids (72%). Hypercarbia was seen in 80% of patients, and 66% had pulmonary hypertension. Unilateral reduction pneumonoplasty by a video-assisted thoracic surgical approach was performed in 34 patients, 6 patients underwent bilateral reduction pneumonoplasty by a video-assisted thoracic surgical approach, and 4 patients underwent bilateral reduction pneumonoplasty by a video-assisted thoracic surgical approach, and 4 patients underwent bilateral reduction pneumonoplasty by median sternotomy. Discrete emphysematous regions were resected using staplers with buttressing, and regions of homogeneous emphysema were plicated with KTP or neodymium:yttrium-aluminum garnet laser radiation. RESULTS: There was one death within 30 days, two additional deaths within 60 days, and five additional deaths within 1 year. Hospital stay averaged 12 days. Intensive care unit stay averaged 4 days. Subjective improvement was noted by 89%. Borg and modified dyspnea scores improved from 7.6 to 4.5 (p < 0.01) and from 3.9 to 2.35 (p < 0.01), respectively. Forced expiratory volume in 1 second was 0.62 L at 1 year, a 51% improvement (p < 0.001). Forced vital capacity was 1.32 L preoperatively and 2.05 L at 1 year (a 56% improvement) (p < 0.001). CONCLUSIONS: This experience documents that patients with severely impaired lung function can successfully undergo operation for emphysema. To obtain these results one must tailor the operative approach to the patient's disease.

Aged↗

PubMed1995

Video-thoracic surgery for treatment of end-stage bullous emphysema and chronic obstructive pulmonary disease.

Surgical treatment of emphysema and chronic obstructive pulmonary disease (COPD) has received renewed attention because of advances in instrumentation and techniques. Our approach includes video-assisted thoracotomy, neodymium-Yag and KTP laser plication of emphysematous bullae, pulmonary resection using reinforced stapling, and pleurodesis: reduction pneumonoplasty. In a 9-month period, 28 patients (age 52 to 78, 23 men and 5 women) with end-stage disease underwent reduction pneumonoplasty. Oxygen therapy was required in 82 per cent, steroid therapy was used in 86 per cent, and the preoperative FEV1 averaged 0.68 +/- 0.05. The most severely diseased lung was determined by physical, chest film, and CT scan, and this lung had reduction pneumonoplasty. There were no hospital mortalities. Prolonged postoperative air leaks occurred in 42 per cent of patients. Postoperatively FEV1 was 0.91 +/- 0.35. Lung size (chest film) showed 21.6 per cent reduction in volume. Subjective improvement was noted in 78.6 per cent (22/28) of patients, and no patient reported worse symptoms. Half of the steroid-using patients required a reduced steroid dose or no steroid therapy, and 5/23 (21.7%) patients had reduced oxygen requirements. Reduction pneumonoplasty can improve the symptoms of severe emphysema and COPD. Our results with treatment of one lung suggest that further improvement may be anticipated by proceeding with surgery for the contralateral lung.

Aged↗

PubMed1991

Excimer laser radiation for endarterectomy of experimental atheromas.

Open laser endarterectomy produces a smooth arterial surface with welded distal end points. This report evaluates 308-nm excimer laser radiation for the laser endarterectomy operation. Arteriosclerotic New Zealand white rabbits (N = 15) were studied. A thoraco-abdominal exploration was performed, the aorta was isolated, heparin was administered, and multiple endarterectomies were performed in each rabbit. A line of laser craters was created at the proximal and distal ends of an atheroma. Laser radiation was used to connect the craters to form the proximal and distal end points. The atheromas were dissected from the aorta with laser light and the end points were fused. The aortas were removed for light and electron microscopy and the animals were sacrificed. Excimer radiation was delivered by a 600-microns fiber at 50 mJ/pulse, 120-ns pulses and either 15- or 20-Hz frequency. At 15 Hz excimer laser endarterectomies showed no perforations along the surface or at the end points. The surfaces were smooth but the end points were not welded in place. At 20 Hz, perforations were seen along 7/11 surfaces and at 5/11 end points. Excimer laser endarterectomy is best performed at 15 Hz. The end points, however, cannot be welded with excimer laser radiation.

Animals↗

PubMed1991

Experimental cholelitholysis with the pulsed tunable dye laser.

This study evaluates the pulsed tunable dye laser with wavelength 504 nm, frequency 10 Hz, and pulse width 1.2 microseconds for cholelitholysis. Power of 10-40 kW was directed through a 250-microns quartz fiber optic to ablate 55 gallstones (removed from 14 patients). The fiber was positioned in direct contact with the stones under saline. Power delivery was begun at 10 kW and increased in 10-kW increments until litholysis began. The range of power and energy necessary to fragment the gallstones was evaluated on four common bile ducts (fresh autopsy specimens). Following fragmentation, all stones were analyzed. There were 35 cholesterol stones (3 calcified) and 20 bilirubin stones (4 calcified). Size ranged from 0.012 to 7.56 cm3 (mean 0.96 +/- 1.41 cm3). Energy necessary for fragmentation ranged from 0.4 to 11.2 J (exposure time 1.0-28 s). Power necessary for fragmentation was 20 kW for 2/55 stones and 40 kW for 53/55 stones. At 40 kW (40 mJ/pulse), common bile duct perforation occurred within 1.1 +/- 0.1 s (0.44 +/- 0.04 J). The pulsed tunable dye laser can fragment gallstones of all compositions. The threshold for fragmentation is 40 kW, but common bile duct perforation occurs at this power. We conclude that laser radiation sufficient to fragment gallstones can injure the common bile duct.

Cholelithiasis↗

PubMed1990

Initial trial of argon ion laser endarterectomy for peripheral vascular disease.

In the initial of open laser endarterectomy, 16 patients underwent 18 reconstructions for claudication (13 patients), rest pain (3 patients), and gangrene (2 patients). The mean (+/- SD) preoperative ankle arm index was 0.53 +/- 0.18. The laser endarterectomies were aorto-bi-iliac (1 patient), iliac (1 patient), superficial femoral (7 patients), profunda femoral (7 patients), and popliteal-posterior tibial (2 patients). All operations included surgical exposure, vascular control, administration of heparin, and an arteriotomy. Atheromas were dissected from arteries with argon ion laser radiation (power, 1.0 W). End points were welded with laser light. Arteries were closed primarily. The laser endarterectomies were 6 to 60 cm long and required 168 J to 2447.5 J. All patients had symptomatic relief, with a postoperative ankle arm index of 0.97 +/- 0.10. There were no arterial perforations from laser radiation. Surgical complications included early thrombosis requiring thrombectomy (3 patients) and hematoma requiring evacuation (1 patient). The laser endarterectomies have an 88% patency at 1 year. Open endarterectomy can be performed with laser radiation. A larger clinical trial is necessary to define the indications for laser endarterectomy in peripheral vascular disease.

Adult↗

PubMed1990

Comparison of contact and free beam laser endarterectomy.

Free beam laser endarterectomy (LE) and contact laser endarterectomy (CLE) were compared in 15 arteriosclerotic New Zealand white rabbits. The rabbits underwent balloon catheter trauma to the thoracoabdominal aorta and were fed a 2% cholesterol diet for 18 weeks. Thoracoabdominal exploration was performed under general anesthesia and multiple endarterectomies were performed in each rabbit. Atheromas were dissected from arteries with laser radiation and end points were welded in place with laser radiation. LEs (N = 8) were performed with argon ion radiation delivered through a 400 microns fiberoptic. Power was kept constant at 1 W and the average fluence was 97.5 +/- 6.6 J/cm2. CLEs were performed with conical sapphire probes powered by either argon ion radiation (N = 12) or Nd-YAG radiation (N = 10). Power used was 1 W to 4 W for each laser. Average argon ion fluence was 117.8 +/- 3.1 J/cm2 and average Nd-YAG fluence was 611.1 +/- 34.4 J/cm2. Following the operations, aortas were removed, fixed, serially sectioned, and stained. Microscopic study revealed welded end points with LE but not with CLE. There were no perforations with LE. There were 11/12 perforations with argon ion CLE and 8/10 perforations with Nd-YAG CLE. Free beam laser endarterectomy is superior to contact laser endarterectomy for experimental atheromas.

Aluminum↗

PubMed1990

Initial clinical evaluation of carotid artery laser endarterectomy.

Clinical study of carotid artery laser endarterectomy began April 15, 1988. This report describes the first 10 cases that were performed in nine patients (five men and four women, mean age 70 years). Indications were asymptomatic stenosis (5), transient ischemic attacks (4), and stroke in evolution (1). There were two emergency cases and eight elective cases (including one reoperative case). Surgical exposure, systemic heparinization, vascular control, and a longitudinal arteriotomy were used. The cleavage plane between atheromas and media was developed with argon ion laser radiation (488 and 514.5 nm) directed through a 300 microns quartz fiber at power 1.0 W. Laser radiation was used to cut the atheromas out of the arteries and weld the end points. Residual atheromatous debris were vaporized with individual laser exposures. Arteriotomies were closed with sutures, and blood flow was restored. The endarterectomies were 3.9 +/- 1.1 cm long and required 330 +/- 97 joules. Mean clamp time was 22.5 +/- 7.9 minutes. Shunts were used in two cases. There were no arterial perforations or injuries as a result of laser light. Complications were hematoma (1), respiratory arrest (1), and transient neurologic deficit (1). Carotid endarterectomy is technically feasible with argon ion laser radiation. In the present series, postoperative observations, averaging 12 months and ranging from 5 to 19 months, have shown satisfactory results. No angiographic follow-up examinations were carried out.

Aged↗

PubMed1989

Myocardial rupture in expanded infarcts: repair using pericardial patch.

Myocardial rupture is found in approximately 20% of fatal infarctions, but the diagnosis is rarely made before death. Rupture occurs in "expanding" transmural infarctions. The diagnosis should be considered in any patient who develops recurrent chest pain and cardiovascular instability within the first week after infarction. Echocardiographic evidence of a dilated infarct with pericardial effusion is confirmatory. Three cases are described, and previous reports are reviewed. Because most patients have multivessel disease, we recommend pericardiocentesis and rapid cardiac catheterization. Infarctectomy may be appropriate when the edges of the lesion are obvious, but the more typical diffuse, serpiginous defects should be closed with dacron-bolstered sutures covered with a wide autologous pericardial patch. Myocardial rupture is a treatable condition, and a high index of suspicion is necessary in order to recognize it more frequently.

Aged↗

PubMed1987

Primary pulmonary angiosarcoma associated with multiple synchronous neoplasms.

A 60-year-old man presented with a 3-month history of shortness of breath. He was found to have a right thoracic mass involving the right middle and lower lobes, pulmonary hilum, and mediastinum. Diagnosis could not be established by pleural fluid cytology, pleural biopsies, bronchoscopy, and ultrasound-guided needle biopsies. A diagnostic exploratory thoracotomy was performed. Massive hemorrhage was encountered upon opening the pleura, and bleeding was controlled by performing a radical pneumonectomy. Histology revealed angiosarcoma, pulmonary primary. The patient survived for 68 days. At autopsy, he was found to have adenocarcinoma of the prostate, adenocarcinoma of the rectum, carcinoid of the ileum, and leiomyoblastoma of the stomach as well as diffuse metastases from the angiosarcoma. This represents the fourth reported case of primary pulmonary angiosarcoma.

Adenocarcinoma↗

PubMed1987

The thrombogenic potential of argon ion laser endarterectomy.

The surface thrombogenicity of atheromas, conventional endarterectomy (CE), laser endarterectomy (LE), and laser angioplasty (LA) were compared in the rabbit arteriosclerosis model. Normal (N = 6) and arteriosclerotic (N = 15) rabbits underwent thoracoabdominal exploration. Multiple CEs and LEs were performed in 12 arteriosclerotic rabbits leaving a segment of intact atheroma between each endarterectomy. Multiple LAs were performed in three arteriosclerotic rabbits. Argon ion laser radiation was used for all laser procedures. Blood (0.05 ml) from normal rabbits was placed on the CE surface, LE surface, LA surface, atheroma, and normal intima and clotting times were determined. Surface thrombogenicity was calculated as the ratio of the clotting time of the CE, LE, LA, or atheroma to normal intima. Surface thrombogenicity was 1.0 +/- 0.03 for normal intima (control), 0.58 +/- 0.06 for atheromas (P less than 0.001), 0.46 +/- 0.08 for CE (P less than 0.001 from atheromas), 0.46 +/- 0.08 for LE (P = NS from CE), and 0.27 +/- 0.09 for LA (P less than 0.001 from CE and LE). The thrombogenicity of LE is the same as the thrombogenicity of CE. Both forms of endarterectomy are less thrombogenic than LA in the rabbit model.

Angioplasty, Balloon↗

PubMed1987

Regional myocardial perfusion of cardioplegic solutions.

We compared the regional myocardial perfusion of blood cardioplegic solution (BCP) and crystalloid cardioplegic solution (CCP) in 14 mongrel dogs. Cardiopulmonary bypass was established at 28 degrees C, and a hydraulic occluder was placed around the proximal left anterior descending (LAD) coronary artery. In group 1 (N = 7) collateral coronary arteries were ligated; in group 2 (N = 7) collateral coronary arteries were left in situ. After the aorta was clamped, BCP and CCP were alternately perfused at 200 ml/min. The occluder was inflated to produce moderate, severe, and critical LAD stenosis, and regional perfusion was measured by xenon-133 washout with the Silicon Avalanche Radiation Detector. BCP infusion produced a consistently higher aortic pressure, but CCP flow was better than BCP flow under all conditions, particularly without coronary collaterals (p less than .05). Regional myocardial perfusion of CCP is superior to BCP.

Animals↗

PubMed1987

Photosensitization of experimental atheromas by porphyrins.

Arteriosclerotic arteries have been shown to fluoresce when treated with hematoporphyrin derivative. This study investigates the incorporation and distribution of a partially purified form of hematoporphyrin derivative (Photofrin II) in normal and arteriosclerotic rabbit aortas. A thoracoabdominal exploration was performed in 15 rabbits. Group I comprised normal rabbits, Group II normal rabbits given 5 mg/kg Photofrin II 48 hours before surgery, Group III arteriosclerotic rabbits and Group IV arteriosclerotic rabbits given 5 mg/kg Photofrin II 48 hours before surgery. Multiple aortic biopsy specimens for frozen section were taken from all rabbits. In addition, open laser endarterectomy (with an argon ion laser) was performed on Group III and Group IV rabbits. Frozen sections were studied by digital video fluorescence microscopy to determine the distribution of Photofrin II within the layers of the aortic wall. The fluorescence of the intima of Group IV rabbits was found to be significantly greater than that of the intima, internal elastic lamina, media or adventitia of the other groups (p less than 0.01) and significantly greater than that of the internal elastic lamina, media or adventitia of Group IV rabbits (p less than 0.01). When open laser endarterectomy was performed, Group III rabbits required 103 +/- 14 J/cm2 and Group IV required 33 +/- 3 J/cm2 (p less than 0.01). It is concluded that porphyrins are selectively localized within the intima of arteriosclerotic arteries. This localization sensitizes atheromas to argon ion laser light and facilitates laser endarterectomy.

Animals↗

PubMed1987

Comparison of continuous-wave lasers for endarterectomy of experimental atheromas.

The standard surgical lasers, argon ion, neodymium-yttrium aluminum garnet, and carbon dioxide, are often operated as continuous wave lasers with specific uses. Clinical trials of laser therapy for arteriosclerotic cardiovascular disease are underway with all three lasers. Therefore, we compared these three lasers under controlled experimental conditions. A thoracoabdominal exploration was performed in 17 arteriosclerotic rabbits. The aorta was isolated, heparin administered, and multiple endarterectomies were performed in each rabbit with each of the lasers. A line of laser craters was created at the proximal and distal ends of an atheroma. Continuous-wave laser radiation was used to connect the craters and thereby form proximal and distal end points. The plaques were dissected free from the aorta with laser light and the end points were fused by laser. The aortas were removed for light microscopy and the animals were killed. The endarterectomy surfaces and end points were serially sectioned and graded according to light microscopic findings (1 = worst, 4 = best). Argon ion laser endarterectomy (N = 16) required 106 +/- 10 J/cm2. The surface score was 3.5 and end point score 3.4. Neodymium-yttrium aluminum garnet laser endarterectomy (N = 13) required 1,289 +/- 115 J/cm2 with a surface score of 2.4 (p less than 0.001 from argon ion) and an end point score of 1.3 (p less than 0.001 from argon ion). Carbon dioxide laser endarterectomy (N = 9) required 30 +/- 5J/cm2 with a surface score of 2.0 (p less than 0.001 from argon ion) and and end point score of 1.6 (p less than 0.001 from argon ion). Perforation occurred in one of 16 argon ion studies (technical error, not laser), in 11 of 13 neodymium-yttrium aluminum garnet studies, and in six of nine carbon dioxide studies. This study demonstrates that of the currently available clinical continuous-wave lasers, the argon ion laser is superior for endarterectomy of experimental atheromas.

Animals↗

PubMed1985

Operative risk factors associated with unstable angina pectoris.

We performed a prospective study in 207 patients with unstable angina pectoris (UA) to identify factors associated with operative mortality (OM) and perioperative myocardial infarction (MI) from myocardial revascularization. The OM was 3.9% (8/207) and the incidence of MI was 11% (23/207). Clinical variables (age, prior MI, electrocardiographic evidence, symptoms, left ventricular function) and operative variables (incomplete revascularization, cardiopulmonary bypass time, cross-clamp time) did not correlate with OM or MI. Operative mortality was associated with critical triple-vessel disease, but not left main coronary artery disease, and accounted for seven of the eight deaths (P less than .01). Myocardial infarction was associated with elective surgery (22/167) as opposed to urgent surgery (1/40) (P less than .01). Therefore, patients with critical triple-vessel disease are the highest risk group for OM, and urgent operation seems to reduce the incidence of MI in patients with UA.

Aged↗

PubMed1985

Laser endarterectomy.

Laser radiation can be applied directly at a diseased artery to dissect the plaque away from the media and perform an open endarterectomy. The appropriate cleavage plane within the media can be achieved with the laser beam for precise reconstruction of the artery. Laser endarterectomy offers a technique for the study of laser radiation upon arteriosclerosis and may become a new modification of a standard surgical technique.

Animals↗

PubMed1985

Laser applications to arteriosclerosis: angioplasty, angioscopy, and open endarterectomy.

We have studied laser radiation of arteriosclerotic cardiovascular disease to determine the best technique for evaluation. Rabbits with arteriosclerosis were treated by intraluminal laser angioplasty (N = 8), laser angioscopy (N = 2), and open laser endarterectomy (N = 5). All studies were performed with an argon ion laser delivering energy through a 400-microns quartz fiber. Power delivered was varied in order to determine the best value for this animal model. Following angioplasty, perforation was seen in three rabbits (in one case, it was due to mechanical trauma from the fiber optic), and early thrombosis occurred in two rabbits. Plaques were vaporized by angioscopy, but the depth of laser beam penetration or angle of incidence could not be controlled. Open laser endarterectomy gave consistently good results with removal of an arteriosclerotic plaque within the media. The optimum power was found to be 1.0-2.0 W. Endarterectomy required an energy density of 100-140 J/cm2. We conclude that open laser endarterectomy can be a standardized technique for the in vivo evaluation of laser radiation upon arteriosclerotic lesions.

Animals↗

PubMed1985

Experimental arteriosclerosis treated by conventional and laser endarterectomy.

Open laser endarterectomy was compared to standard surgical endarterectomy in the rabbit arteriosclerosis model. The aorta was exposed by a thoracoabdominal exploration in 16 rabbits. In Group I (8 rabbits), a conventional endarterectomy (CE) was performed with standard vascular instruments. In Group II (8 rabbits), laser endarterectomy (LE) was performed with an argon ion laser (488 nm and 514.5 nm) at a power of 1.0 W. Aortas were fixed, serially sectioned (6 micron) and stained (H +/- E) following each procedure. Gross and light microscopic examination revealed identical results for the endarterectomy surfaces of CE and LE. The proper cleavage plane within the media was developed with both techniques and the remaining arterial wall was not damaged with either procedure. The end points of LE were consistently superior to those of CE because of phototherapy fusion. The LE end points were tapered and the intima was fused. Intimal flaps were seen in 2/8 CE experiments and the remaining end points exhibited an uneven transition. LE required an average energy density of 124 +/- 9 J/cm2. We conclude that LE provides a satisfactory method for the in vivo evaluation of laser radiation upon arteriosclerotic arteries. LE may be the way to begin clinical laser trials.

Animals↗