Computed tomography and the TNM classification of lung cancer.

Computed tomography (CT) of the thorax and upper abdomen was prospectively evaluated in 84 patients with potentially operable lung cancer. Invasion into the thoracic wall and the mediastinal structures was not accurately demonstrated by CT. For metastatic mediastinal lymph nodes, the sensitivity and specificity of CT were, respectively, 86% and 61% and the positive and negative predictive indices 49% and 91%. For T1, T2 and T3 tumours the negative indices were 100%, 96% and 71%. Positive predictive index did not differ between squamous cell carcinoma and adenocarcinoma. Adrenal metastases were CT-suspected in 17 cases and liver metastases in eight, but were verified by ultrasonography in only one and four cases. CT should be used in preoperative investigation of lung cancer, irrespective of stage. Demonstration of thoracic-wall or mediastinal invasion need not exclude tumour resection. Preoperative mediastinoscopy is indicated if CT shows nodal metastases or if there are signs of tumour invasion, but not in CT-negative T1 or T2 tumour. Abdominal metastases indicated by CT should be investigated with CT-guided needle biopsy.

57Co-bleomycin scintigraphy for the preoperative detection and staging of lung tumors.

Twenty-five consecutive patients with lung tumors were classified according to the presence of metastases by the use of 57Co-Bleomycin scintigraphy. Twenty-two of the tumors were visualized but metastatic spread to hilar lymph nodes was not detected. Reliable separation of central tumors with and without growth into neighbouring organs was not possible. Mediastinal uptake was found in eight cases but only a part of these could be verified by operation. The method can contribute to the evaluation of lung tumors and can be helpful to avoid some unnecessary thoracotomies.

Five years experience with treatment of lung cancer. The role of mediastinoscopy.

Over a five-year period, 304 patients with non small cell carcinoma of the lung were evaluated for pulmonary resection. The patients were divided into three groups: 1) 180 patients operated without preoperative mediastinoscopy based on a normal appearing mediastinum on plain chest x-ray; 2) 107 patients with resection of both lung tissue and mediastinal tissue due to localised positive mediastinoscopic findings; 3) 17 patients who were found inoperable either due to poor lung function or diffuse mediastinal seeding. In group 1, 24% were peroperatively found to be inoperable due to mediastinal involvement. The rest were resected and received no further therapy. In group 2, 84 patients were resected and postoperatively irradiated on the mediastinal area. The incidence of bronchopleural fistulae in group 1 was 0.7% and in group 2 16%, and the survival at any period was significantly poorer for group 2 than for group 1. We conclude that every patient with pulmonary infiltrates must be subjected to mediastinoscopy before thoracotomy and should be excluded from operative intervention in the presence of positive mediastinoscopic findings.

Transcervical thymectomy in patients with nonthymomatous myasthenia gravis.

Transcervical thymectomy was performed during a 13-year period in 21 patients with nonthymomatous myasthenia gravis. Follow-up showed that only eight patients benefited from the operation. These eight were among the younger patients in the series. This observation is discussed, and also the theoretic background for early thymectomy. The transsternal approach is recommended for thymectomy in elderly patients, but the transcervical may be considered for younger patients, although transsternal reexploration is advocated if this first operation should fail.

Surgical improvement of patients with pulmonary insufficiency due to localized bullous emphysema or giant cysts.

Patients with continuous expansion of either giant lung cysts or areas of localized bullous emphysema will eventually deteriorate into a state of extreme respiratory distress due to compression of the remaining healthy pulmonary tissue. Thirty-one patients with these 2 types of lung disease having very poor respiratory function underwent surgery for the release of compromised healthy lung by resection of the expanding processes. A rational investigation program including respiratory tests, ventilation and perfusion scintigraphy and pulmonary angiography was gradually developed and analyzed. Surgical mortality was 12.9% in unilateral operations, probably somewhat higher in later contralateral interventions. The operative risk was higher in the emphysema group than in the group with giant lung cysts. Follow-up has demonstrated encouraging results in both groups concerning increased pulmonary function as well as improved working capacity.

Early surgical intervention in non-specific pleural empyema.

During a 4-year period, 18 patients were treated for non-specific pleural empyema. Nine patients were treated by closed intercostal drainage and 9 by early decortication. The length of time from initial treatment until complete resolution of the empyema and healing of the wound was compared between the groups and highly favored early surgery. We conclude that if an empyema does not show signs of regression after one week of drainage, surgical intervention is indicated.

Clinical experience with porcine xenografts in the mitral position.

In a 7-year period, 120 porcine xenografts, 16 of Hancock and 104 of Carpentier-Edwards type, were implanted in the mitral position in patients with isolated mitral valve disease. The operative mortality was 4.2%. The actuarial survival after 5 years was 93%. Death during the observation period was valve-related in two cases. Three valves had to be exchanged, one because of calcification and two because of prosthetic endocarditis. The risk of contracting prosthetic endocarditis was 0.38% per patient year. All the patients received peroral anticoagulant medication indefinitely. Two minor embolic episodes occurred, both in the first 6 post-operative months. The probability of freedom from thromboembolism was thus 98.2% after 7 years. In functional evaluation of 92 patients observed for at least 6 months, more than 90% were in NYHA class I or II. Porcine xenograft is a good valve substitute in the mitral position with a low incidence of complications, especially of thromboembolism, in patients on maintenance anticoagulant therapy. Long-term observations of this type of valve substitute are not yet available, however.

A hemodynamic study of the Carpentier-Edwards and Hancock porcine xenografts in the mitral position.

A hemodynamic study was performed on 11 female and 3 male patients with porcine xenograft (9 Carpentier-Edwards, 5 Hancock) in mitral position on average 32.5 months (range 10-65 months) after the operation. In comparison with the preoperative values, the following parameters showed statistically significant post-operative decrease (mean values): wedge pressure (from 22.9 to 13.7 mmHg), pulmonary artery pressure (33.6-21.7), right atrial pressure (7.1-4.2) and pulmonary vascular resistance (3.6-1.9 mmHg/l/min). In a supine bicycle exercise test the mean wedge pressure rose to 27.8 (range 15-44) mmHg. The transvalvular average diastolic gradient showed a mean value of 6.9 (range 4-12 mmHg). The corresponding figures for the calculated valve area were 2.0 (1.0-3.5) cm2. A biplane left ventriculography showed no valvular or paravalvular regurgitation to the left atrium in any patient. The wedge pressures during exercise were significantly correlated with graft diameters. The results were compared with previous reports on mechanical and biological mitral prostheses, and it was concluded that implantation of a porcine xenograft in the mitral position is a satisfactory procedure in severe mitral disease.

Immediate and long-term results in aortic valve replacement.

In a 12-year period, 127 patients with isolated aortic valve disease underwent valve replacement surgery. Long-term results are presented in regard to patients with operation between 1967 and 1974 and immediate results in the later cases. The main conclusions from the study are that the type of myocardial protection is important for the perioperative mortality rate. This rate was 18% in patients operated on in normothermia and 6% in those with chemical cardioplegia. No significant correlation was found between preoperative NYHA grouping and mortality or complication rate, and the long-term result was independent of the type of valvular prosthesis.

Primary malignant fibrous histiocytoma of the lung. A case report.

A case of malignant fibrous histiocytoma of the lung is presented and the literature concerning this rare tumour is reviewed. The advisability of postoperative chemotherapy in the cases remains to be clarified and further data are required to establish the optimum management.

Myocardial preservation during anoxic arrest. Chemical cardioplegia.

Two types of cardioplegic solution--the potassium arrest and the Bretschneider solution, both at 4 degrees C--were compared with regard to protective effect against ischemic damage during 60 min of anoxic cardiac arrest in the dog heart. Both solutions provided equally good protection, which was superior to that given by hypothermia alone.

Myocardial preservation during anoxic arrest. Premedication with propranolol, verapamil or methylprednisolone.

Anoxic cardiac arrest was studied for one hour in five groups of dogs. Groups I-III were given methylprednisolone (30 mg/kg b.w.) before aortic cross-clamping. Normothermia was used with electrically induced ventricular fibrillation in group I, and without such fibrillation in group II, while group III was studied in local hypothermia. Propranolol (10 micrograms/kg) was given to group IV and verapamil (0.2 mg/kg) to group V before the anoxic arrest in local hypothermia. Judged from the ability of the heart to take over the circulation after anoxic arrest, local cooling preceded by propranolol or verapamil gave working performance comparable with the pre-arrest values. In the cooled, steroid-pretreated hearts the work capacity was depressed to the same degree as in locally cooled hearts without steroid premedication. Methylprednisolone prevented ischemic contracture during normothermic arrest with induced fibrillation, but not in the absence of such fibrillation. As adjuvant to local cooling, pretreatment with metabolism-reducing drugs is favorable for cardiac performance after arrest. Steroid premedication should be considered when normothermic arrest with electrically induced ventricular fibrillation is planned.

Intramyocardial temperature following various cooling procedures.

In 12 dogs on cardiopulmonary bypass, the intramyocardial temperatures in the anterior and the posterior wall of the left ventricle and in the septum were measured with microthermoelectrodes when different cooling procedures were used during 60 min of anoxic cardiac arrest. External cooling with 4 degrees C glucose (5.5%) solution dripping into the pericardial sac did not lower the temperature in the septum or in the posterior wall. Packing the heart in slushed ice after injection of the same glucose solution into the coronary tree reduced the septum and posterior wall temperature to around 30 degrees C. This cooling procedure, in combination with general moderate hypothermia, lowered the temperature to about 20 degrees C in these parts of the heart. Only when combined with general hypothermia did local cooling achieve low temperatures in all regions of the myocardium.