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P Stulz

Publications and source records attributed to P Stulz.

At least 55 records · Page 3Linked to original sources
PubMed1995

Exercise capacity as a predictor of postoperative complications in lung resection candidates.

Exercise testing with measurement of maximal oxygen uptake (VO2max) is increasingly used in the assessment of lung resection candidates, but its predictive value for postoperative complications remains controversial. We therefore sought to determine the prognostic value of VO2max compared with other pulmonary function tests. A consecutive group of 80 patients (mean age 61 yr; 57 males and 23 females) scheduled for lung resection (62 malignancies, 12 benign disorders, and 6 carcinoids) underwent pulmonary function tests and symptom-limited cycle ergometry. All patients underwent lung resections: 21 pneumonectomies, 45 lobectomies, and 14 segmental or wedge resections. Group A (64 patients, 80%) had an uneventful postoperative course, whereas Group B (16 patients, 20%) had complications; 3 of them died (4% overall mortality rate). In a stepwise logistic regression analysis used to determine independent risk factors for postoperative complications (within 30 d), VO2max expressed as a percentage of predicted (84 +/- 19 for Group A versus 61 +/- 11 for Group B) proved to be the best predictor (predictive value 85.5%). Although VO2max expressed in absolute values (ml/kg/min) was also highly predictive (79.5%), a ROC curve analysis proved the percentage predicted values to be significantly more sensitive. Of 9 patients with a VO2max < 60% of predicted, 8 had complications, including all 3 patients who died after resections of more than one lobe (sensitivity 50%, specificity 98%). The estimated probability (probit model SAS software package) of suffering no complication was 0.9 for VO2max > 75% of predicted and 0.1 for a VO2max < 43%.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

[Electrocoagulation in patients with cardiac pacemakers: what should be considered?].

Since the early days of pacemaker development electromagnetic interference (EMI) has always been a major concern and challenge to engineers, producers and physicians. The latter has to be aware of adverse effects of certain electric medical devices used near or on a patient carrying a pacemaker. Although highly sophisticated circuits and filters inside modern pacemakers can reject most EMI, concerns still remain and normal pacemaker function can be affected. EMI can be triggered by a variety of medical devices such as electrocautery, magnetic resonance imaging, diathermy, cardioversion and defibrillation, therapeutic radiation and lithotripsy. This article addresses the possible effects of electrocautery and the precautions that should be taken in case such a device has to be used on a patient with a pacemaker.

Contraindications↗
PubMed1995

[Strategy for staging non-small cell bronchial carcinoma (NSCLC) with special reference to imaging procedures].

Imaging methods, especially CT and for specific questions MRI, are an essential part of diagnosis and staging of non-small cell lung cancer. They are effective methods for the detection of unresectable tumours and avoid the necessity for further invasive examinations and explorative thoracotomies. The judgement of lymph node size by CT suffers from a limited accuracy. Nevertheless, it allows guided bronchoscopical staging biopsies of enlarged mediastinal lymph nodes (> 1 cm) and, therefore, a selective indication of mediastinoscopy. CT scans of the thorax usually are extended to the adrenal glands and the liver to exclude metastasis. Extrathoracic scanning beyond the upper abdomen and bone scintigraphy should be restricted to patients with clinical indicators or symptoms. The combined application of imaging methods, bronchoscopy, and mediastinoscopy provides better selection of surgical candidates and hence reduces the rate of unresectable operations.

Bronchoscopy↗
PubMed1994

[Massive intraoperative pulmonary embolism. Diagnosis and control following embolectomy with transesophageal echocardiography].

Massive intraoperative embolism is a life-threatening condition that may lead to immediate death. Important for the survival of the patient are rapid diagnosis and prompt surgical embolectomy. Case report. Nineteen days after a traffic accident, a 67-year-old patient who had complex ligamentous injuries was operated upon on both knees during general anaesthesia. The operation progressed uneventfully for the first 30 min when the patient's systolic blood pressure became slightly unstable and decreased to 85 mm Hg despite administration of ephedrine and infusion of hetastarch. This was followed 30 min later by an immediate drop to values that were undetectable on an oscilloscope. The pulse oximeter no longer detected a signal at the finger-tip and the end-tidal CO2 decreased to 1 kPa (7.5 mm Hg). To confirm the diagnosis of an acute pulmonary embolism, we performed transoesophageal echocardiography (TEE) and found a large amount of free-floating material in the right atrium, a dilated and hypokinetic right ventricle, and a collapsed left ventricle (Fig. 1 a). Embolectomy was immediately started using the inflow-occlusion technique supported by cardiopulmonary bypass (CPB). All emboli were removed from the right atrium and pulmonary artery (Fig. 1 b). During closure of the sternotomy, heart function was monitored by TEE and we again noted large emboli in the right atrium (Fig. 1 c). To remove these, we reinstated CPB and then placed an inferior vena cava filter. The final TEE control showed free heart chambers with good contractility (Fig. 1 d).(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1994

Decision making in the surgical treatment of massive pulmonary embolism.

Pulmonary embolectomy in the treatment of acute massive pulmonary embolism (PE) is the subject of considerable controversy with regard to indication, technique of embolectomy and perioperative management. Since 1968 50 patients have undergone surgery for massive PE in our unit. Inflow occlusion technique and cardiopulmonary bypass were used in 33 and 17 patients, respectively. The overall operative mortality was 46%. Univariate analysis disclosed age (< 60 vs > 60), preoperative hemodynamics (cardiogenic shock vs cardiac arrest), location of emboli (peripheral vs central), duration of symptoms (hours vs days vs weeks) and number of episodes (first episode vs recurrent pulmonary emboli) as predictive factors of the post-operative outcome. The results of the retrospective analysis show that pulmonary embolectomy remains an acceptable procedure in patients with acute massive pulmonary emboli who are in refractory cardiogenic shock or who need intermittent resuscitation.

Cardiopulmonary Bypass↗
PubMed1994

Primary non-Hodgkin's lymphoma of the lung. Will videothoracoscopic biopsy change decision-making with regard to resection of this disease?

We report on a 57-year-old male presenting with cough and chest pain as well as a chronic infiltrate in the right posterior basel segment. Antibiotic treatment had been unsuccessful, CT-guided needle-biopsy and bronchoscopy had failed to forward reliable results. Thus, videothoracoscopic biopsy was performed and histologic diagnosis of a low-grade non-Hodgkin's lymphoma was obtained. The tumor was left in situ and single-agent chemotherapy was initiated for reasons which are discussed. Up to now localized pulmonary lymphomas were mainly resected in the course of an exploratory thoracotomy because the disease often could not be diagnosed with certainty previously. It is discussed whether surgical resection is still the best choice or other treatment modalities should be preferred.

Biopsy↗
PubMed1994

Costotomy and "hand inside": a useful adjunct to video-assisted thoracic surgery or just a silly idea?

We report on our first experiences with an access in video-assisted thoracoscopic surgery (VATS) which to the best of our knowledge has not yet been reported. One of the main problems in VATS is the absence of palpation which evidently plays an important role in tumor surgery. In three cases we therefore performed dorsolateral 8 cm incisions just beneath the scapula and resected a corresponding length on 6th or 7th rib to be able to insert one hand into the thorax. No rib-spreader was used in either case, the idea being that a small costotomy would be less painful and traumatic than a standard posterolateral thoracotomy. Visualization of the operative field was obtained by inserting a camera through the 9th intercostal space, one or two additional small incisions were made for the other instruments.

Adenocarcinoma↗
PubMed1994

Aortic valve replacement in elderly patients with aortic stenosis.

OBJECTIVE: To assess the risk of aortic valve replacement and long-term follow-up in elderly patients with dominant aortic stenosis. DESIGN: Retrospective analysis of patients who had aortic valve replacement over a 10 year period and were routinely seen in an outpatient clinic. SETTING: University hospital. PATIENTS: 93 patients aged > or = 60 and 47 patients > or = 70 years with symptomatic aortic stenosis undergoing aortic valve replacement. MAIN OUTCOME MEASURES: Early and late mortality in different age groups. Influence of preoperative signs and symptoms on overall outcome. RESULTS: The proportion of patients older than 70 years increased from 11% in 1978 to 54% in 1986. Perioperative mortality was 3.6% and mortality after 2 and 5 years was 9% and 13% respectively. Survival was similar (85% and 83%, respectively) in patients aged 60-69 years (group 1, n = 93, mean age 64.5 (2.7) and patients aged > or = 70 years (group 2, n = 47, mean age 72.6 (2.5)). Additional coronary artery disease and coronary bypass grafting did not significantly affect survival. The cardiothoracic ratio was inversely related to survival (Cox regression, p < 0.05). Preoperative symptoms (syncope, angina pectoris, and dyspnoea) were similar in both patient groups. After a mean (SD) follow up of 51 (33) months 96% of surviving patients were in NYHA functional class I or II with no difference between the two age groups. Similarly, the cardiothoracic ratio and Sokolow index decreased to near normal values in both age groups. CONCLUSION: The risk of aortic valve replacement in patients with dominant aortic stenosis is low and not significantly influenced by age. Therefore replacement may be performed without increased risk in elderly patients and with a good long-term outcome.

Age Factors↗
PubMed1994

Evaluation of high-risk lung resection candidates: pulmonary haemodynamics versus exercise testing. A series of five patients.

We compared the value of exercise testing and measurement of pulmonary haemodynamics (PH) in the pre-operative assessment of 5 patients (mean age: 64 years, 3 men) with clinical stage I or II bronchogenic carcinoma and severe chronic obstructive pulmonary disease. They were considered at high risk due to poor pulmonary function tests (PFT); (one or more of the following): (1) radionuclide calculated postlobectomy FEV1 < 30% predicted, (2) diffusion capacity or transfer factor < 60% predicted, combined with a fall in PaO2 on maximal exercise of > 5 mm Hg, (3) a PaCO2 at rest of > 45 mm Hg. Maximal oxygen uptake (VO2max) during symptom-limited cycle ergometry and PH were measured in these 5 patients. They were considered eligible for lobectomy if they fulfilled at least one of the two criteria: (1) mean pulmonary artery pressure (PAP) of < 35 mm Hg and pulmonary vascular resistance of < 190 dyn.s.cm-5 at moderate exercise (40 W), (2) a VO2max of > or = 15 ml/kg/min. Six months postoperatively PFT and VO2max were measured again. PAP40W was 21, 38, 38, 46 and 52 mm Hg, respectively, which would have excluded 4/5 patients from surgery. VO2max was 21.7, 14.9, 13.4, 19.2 and 18.6 ml/kg/min, respectively, which would have excluded 2/5 patients. Expressed in percent predicted, however, VO2max was > or = 69% in all 5 patients, indicating only mild impairment of exercise capacity in the 2 patients with < 15 ml/kg/min VO2max. Therefore all 5 patients were offered surgery and underwent lobectomy. Apart from 1 prolonged air leak no complications occurred, the mean hospital stay was 16 days (13-21).(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1993

The Omnicarbon tilting-disc heart valve prosthesis. A clinical and Doppler echocardiographic follow-up.

From 1986 to 1990, 172 patients with a median age of 60.5 years (range 20 to 79 years) received 187 Omnicarbon valves (109 aortic valve replacements, 48 mitral valve replacements, and 15 double valve replacements). Patients were followed-up for a median observation period of 2.5 years (range 4 months to 5.2 years) by clinical and Doppler echocardiographic examination. Follow-up was complete in 98%. Operative mortality (death within 30 days) was 1.7%, and linearized late mortality was 2.6% per patient-year, corresponding to an actuarial survival rate for operative survivors of 89% after 4 years. The overall 4-year postoperative survival was 87% (93% for aortic valve replacement, 77% for mitral valve replacement). Compared with age- and sex-adjusted Swiss death rates, there was an excess mortality of 5% after 4 years. Percentages for freedom from valve-related complications at 4 years are as follows: thromboembolism, 98% (aortic valve replacement, 98%, and mitral valve replacement, 96%); anticoagulant-related hemorrhage, 95%; valve endocarditis, 96%; reoperation, 96%; and permanent valve-related impairment, 99%. The overall 4-year event-free survival was 76% (80% for aortic valve replacement and 69% for mitral valve replacement). New York Heart Association class improved in 88% of the patients by 1 to 3 grades, and only 3% remained in class III after operation. For the most commonly used aortic valve (23 mm), Doppler echocardiography revealed a peak pressure gradient of 29 +/- 10 mm Hg, a fractional shortening/peak pressure gradient ratio of 1.34 +/- 0.61, and a performance index of 0.35 +/- 0.08. In the most commonly used mitral valve (27 mm), the mean pressure gradient was 4.0 +/- 2.1 mm Hg. We conclude that excellent clinical and hemodynamic results can be obtained with the Omnicarbon prosthesis, in both the aortic and mitral positions.

Adult↗
PubMed1992

[Possibilities and limitations of surgical therapy in acute and chronic heart failure].

Five out of the many scenarios for surgical interventions in manifest or imminent heart failure that are of special importance for the practitioner as well as the attending physician are covered. In the context of acute heart failure, mechanical complications of infarction and acute aortic insufficiency in the course of infectious endocarditis are discussed. In a second part, heart failure in chronic regurgitation of the aortic valve and chronic ischemic heart disease are treated. Main attention is given to medical indication for surgical intervention.

Acute Disease↗
PubMed1992

[Role of antibiotics in surgically treated active endocarditis].

In a retrospective study of 30 patients in whom a valve was replaced during active endocarditis, the role of the concomitant antimicrobial therapy was analyzed. In 75% of the patients with less than 1 week of adequate treatment before surgery, but only in 13% (p less than 0.001) with at least 1 week of therapy, could the microorganism be cultivated from the excised valve. Patients with bacteria on the valve had a 4-fold increased risk for prosthetic valve endocarditis and 2.7-fold more frequent paravalvular leakage. Therefore, in the absence of severe cardiac failure, the valve replacement should not be performed before the second week of therapy. Patients in whom microorganisms can be cultivated from the valve need a complete postoperative course of antimicrobial therapy.

Adult↗
PubMed1992

Cell cultures from cryopreserved human lung tissue.

To assess gene induction in primary human fibroblasts, we have developed a method for cryopreservation of lung biopsies in liquid nitrogen. Fresh biopsies (n = 10) were chopped into 5 x 5 mm pieces and transferred into an ice-cold freezing medium. Biopsies were kept on ice for 15 min, followed by further cooling of the tissue to -70 degrees C. With this method, lung biopsies were preserved for more than 1 year before they were used for generating cell cultures. There was no significant difference in the biological responsiveness of fibroblasts generated from immediately cultured lung biopsies compared with those from cryopreserved tissue. The doubling rate of fibroblasts from fresh tissue was 23.6 +/- 1.1 hr; compared to 23.5 +/- 1.5 hr for fibroblasts generated from cryopreserved tissue. PDGF-BB enhanced de novo synthesis of DNA 100 times, in both the immediately cultured fibroblasts and those generated from cryopreserved biopsies. Macrophages, dendritic cells and endothelial cells could also be recovered from cryopreserved lung tissue. This method permits long-term storage of lung tissue and the possibility of establishing primary cell lines from the same tissue at later times without appreciable changes in their cellular biological characteristics.

Cell Cycle↗
PubMed1992

Different effects of activated platelets in the right gastroepiploic and internal mammary arteries. Implications for coronary artery grafting.

The right gastroepiploic artery is increasingly utilized as an alternative coronary bypass conduit, although postoperative spasm can represent a problem. Platelet-vessel wall interactions are important determinants of graft function and patency. We studied the effects of activated platelets in porcine and human gastroepiploic and mammary arteries. Arterial rings were suspended in organ chambers for isometric tension recording. In the porcine and human gastroepiploic arteries with or without endothelium contracted with norepinephrine, activated platelets evoked only further and strong contraction. In contrast, in the porcine and human mammary arteries, endothelium-dependent relaxations to platelets mediated by nitric oxide were noted, particularly in rings preincubated with the thromboxane A2 receptor antagonist SQ-30741 and the 5-hydroxytryptamine (5HT2)-serotonergic receptor antagonist ketanserin. Although endothelium-dependent and endothelium-independent relaxation to bradykinin and the nitrovasodilator 3-morpholino sydnonimine were more pronounced in the gastroepiploic than in the mammary artery, norepinephrine, serotonin, and potassium chloride evoked much stronger contractions in the former than in the latter. Thus activated platelets induce pronounced contraction of the gastroepiploic artery that may contribute to postoperative spasm. The administration of antiplatelet drugs and vasodilators that prevent the effects of thromboxane A2 and serotonin may be beneficial for gastroepiploic graft function.

Adenosine Diphosphate↗
PubMed1992

[Traumatic aortic rupture--an emergency indication?].

On the basis of a retrospective analysis that included 22 patients with traumatic rupture of the thoracic aorta, the appropriate time for surgical intervention will be evaluated. The patients were divided into two groups according to their clinical status at the time of surgery. Seven patients with unstable vital systems underwent immediate surgery; 5 out of 7 died intraoperatively. Because of either the surgeons decision or delayed diagnosis, 15 patients underwent surgical repair of the aorta after various time intervals; 3 of these expired late after the operation. These results indicate that the timing of surgical intervention in the stable covered aortic rupture with serious associated injuries should preferably be deferred until after the patients condition has stabilized.

Aorta, Thoracic↗
PubMed1991

Allelic loss on the short arm of chromosome 11 in non-small-cell lung cancer.

Forty-eight samples of primary non-small-cell lung cancer (NSCLC) and normal tissue from the same patients were analyzed for allelic deletions on chromosome 11p. Five polymorphic loci were assessed to determine the incidence of 11p sequence deletions and to define hot-spots of deletions. Information was obtained from all patients in at least one locus. Our data show that the deletions observed were not randomly scattered over the short arm of chromosome 11. Rather, 2 hot-spots of deletions were observed: one in the area of the genes for catalase and beta-FSH corresponding to band 11p13, the other close to the IGF-II locus corresponding to band 11p15. A high incidence of loss of heterozygosity (LOH) was found with the probe for catalase (21/29), a locus flanking the centromeric region of the Wilms' tumor locus. Most of the samples exhibiting LOH of one or more of the alleles analyzed remained heterozygous for at least one other chromosome 11p allele. Furthermore, duplication of the intensity of the remaining allele was rarely observed. Our results indicate that LOH on the short arm of chromosome 11 is a common event in NSCLC and that the chromosomal region containing the Wilms' tumor locus is most commonly involved.

Alleles↗
PubMed1991

Different interactions of platelets with arterial and venous coronary bypass vessels.

We studied the interaction of platelets with the wall of human internal mammary arteries and saphenous veins, suspended in organ chambers for measurement of isometric tension. Vessels were obtained during coronary bypass surgery and cut into 5 mm rings; in some the endothelium was chemically removed. Rings from several patients were randomly chosen for each experiment, and in each ring six concentrations of platelets (from healthy blood donors; 1-75 x 10(3)/microliters) were tested consecutively and concentration-response curves constructed; the areas under these curves were used for statistical comparisons. In rings of internal mammary artery contracted in response to noradrenaline, aggregating platelets induced endothelium-dependent relaxation which was prevented by apyrase (0.67 U/ml ADPase activity) and L-NG-monomethylarginine (1 mmol/l). By contrast, in saphenous vein rings contracted in response to noradrenaline, aggregating platelets induced only a further increase in tension. In quiescent vessels, the platelet-induced contraction did not occur in arteries with endothelium but that in veins was greater and facilitated by endothelium. Preincubation of platelets with aspirin (10 mumol/l) reduced the contraction in both vessels, but contraction was abolished only in the presence of both the thromboxane receptor antagonist SQ-30741 and the serotoninergic (5HT2) receptor antagonist ketanserin. These findings show that platelet-derived ADP causes release of nitric oxide by the endothelium of internal mammary artery but not of saphenous vein; thromboxane A2 and serotonin mediate contraction in vein but not artery with endothelium. These differences may contribute to differences in graft function and the clinical efficacy of antiplatelet drugs.

Apyrase↗