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951.
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953.
Background/Purpose: Aortosternopexy from a left anterolateral thoracotomy is the procedure of choice in severe tracheomalacia. The authors report an alternative technique of modified thoracoscopic aortopericardiosternopexy. Methods: Thoracoscopy under mild CO2 insufflation (insufflation pressures 4 to 6 mm Hg) provides excellent access without selective intubation. The importance of visualizing the phrenic nerve, mobilization of the thymus without disrupting its vascular supply, and intraoperative bronchoscopy is stressed. The technique of passing the needle through the sternum and back is shown. In long segment tracheomalacia, not only the ascending aorta, but also the innominate artery and base of the pericardium are fixed to the sternum, and the effect is monitored by intraoperative bronchoscopy. Results: This technique was dramatically successful in a 4-year-old boy with long segment tracheomalacia and as a redo procedure in a 2-year-old girl after failed open aortopexy. Conclusion: Thoracoscopic aortopexy seems to be as effective as open aortopexy. J Pediatr Surg 37:1476-1478.  相似文献   
954.
OBJECTIVES: It has been proved in human subjects and animals that atelectasis is a major cause of intrapulmonary shunting and hypoxemia after cardiopulmonary bypass. Animal studies suggest that shunting can be prevented entirely by a total vital capacity maneuver performed before termination of bypass. This study aimed to test this theory in human subjects and to evaluate possible advantages of off-pump coronary artery bypass grafting. METHODS: Twenty-four patients scheduled for coronary artery bypass grafting were randomly assigned to receive no total vital capacity maneuver (control group, n = 12) or standard total vital capacity maneuvers (TVCM group, n = 12). Additionally, 12 consecutive patients undergoing off-pump coronary artery bypass grafting (off-pump group) were studied. Systemic and central hemodynamics, the pattern of breathing, and ventilatory mechanics were evaluated after induction of anesthesia, after sternotomy, after cardiopulmonary bypass and skin closure, and 4 hours after extubation. RESULTS: The use of total vital capacity maneuvers reduced (P <.05) intrapulmonary shunting after termination of cardiopulmonary bypass. However, shunting increased (P <.05) in all groups (control group, 8.2% +/- 3.3% vs 25.6% +/- 8.1%; TVCM group, 8.7% +/- 3.4% vs 24.4% +/- 8.5%; and off-pump group, 7.8% +/- 2.8% vs 14.0% +/- 5.3%) after extubation, but the increase was significantly (P <.05) less pronounced in the off-pump group. Furthermore, pulmonary compliance decreased (P <.05) in all groups except the off-pump group after extubation. Duration of hospital and intensive care unit stay was significantly shorter (P <.05) in the off-pump group than in the other groups. CONCLUSION: The development of intrapulmonary shunting and hypoxemia after coronary artery bypass grafting can be substantially reduced by performance of total vital capacity maneuvers while patients are mechanically ventilated. However, off-pump coronary artery bypass surgery is superior in preventing shunting and hypoxemia after bypass grafting in the immediate and early postoperative periods, probably leading to substantially shorter intensive care unit and hospital stays.  相似文献   
955.
Prager G  Kalaschek A  Kaczirek K  Passler C  Scheuba C  Sonneck G  Niederle B 《Surgery》2002,132(6):930-5; discussion 935-6
BACKGROUND: Many patients with primary hyperparathyroidism (PHPT) show symptoms of hypercalcemia syndrome, including psychologic and psychiatric disorders. The aim of this study was to find out whether parathyroidectomy improves cognitive performance with regard to concentration and retentiveness in patients with PHPT. METHODS: . Twenty patients with PHPT underwent psychologic testing preoperatively as well as 6 and 12 weeks postoperatively. Concentration under stress (timing) was proved by the d2-Test of Attention. To evaluate retentiveness, parts of the Wilde Intelligence Test were used. Patients were tested under identical circumstances with regard to time, location, and tester to minimize exterior influences. RESULTS: The patients' concentration enhanced significantly postoperatively (P <.001). The same applied to the total number of items processed (P <.01). Improvement of patients' ability to memorize numbers reached statistical significance when comparing the preoperative with the postoperative result (P =.0396); furthermore, there was a tendency to perform the tests more carefully and accurately (P =.069). CONCLUSIONS: Parathyroidectomy not only betters physical symptoms of PHPT but can also positively influence the patients' cognitive performance. These findings reflect the clinical observation of the patients' improved mental capacity after parathyroidectomy.  相似文献   
956.
BACKGROUND: Patients suffering from hepatic metastases of neuroendocrine tumors (NET) are potential candidates for orthotopic liver transplantation. Because recurrence rates are high and outcome is variable, prognostic indicators are required. The aim of our study was to identify predictors of long-term survival with a focus on the impact of tumor biology. METHODS: We retrospectively analyzed 19 patients who received an orthotopic liver graft for metastatic NET at the Medizinische Hochschule Hannover. Expression of Ki67, E-cadherin, and p53 was studied immunohistochemically in metastases of neuroendocrine tumors of the explanted livers. RESULTS: Patients were followed up to 146 months after liver transplantation. Six patients died during follow-up. The resulting 1-, 5-, and 10-year survival rates are 89%, 80%, and 50%, respectively. All deaths during long-term follow-up were tumor-associated. Recurrence was diagnosed in 12 patients between 2 weeks and 48 months after liver transplantation. Three patients are without tumor recurrence more than 8 years after liver transplantation. Survival in the 5 patients with low Ki67 and regular E-cadherin staining was significantly better than in the 12 patients with high Ki67 or aberrant E-cadherin expression (7-year survival 100% vs. 0%, respectively, log rank P=0.007). p53 expression did not significantly improve prognostic accuracy. CONCLUSIONS: We conclude that analysis of Ki67 and E-cadherin expression may improve the identification of patients with a favorable prognosis after liver transplantation for metastatic neuroendocrine tumors.  相似文献   
957.
IMPLICATIONS: This case report shows that atelectasis of the left lung-induced by extrinsic compression of the left main bronchus by an aortic aneurysm and persisting despite aggressive conservative treatment-may be effectively treated by bronchial stenting and high-frequency percussive ventilation.  相似文献   
958.
Krieter H  Denz C  Janke C  Bertsch T  Luiz T  Ellinger K  Van Ackern K 《Anesthesia and analgesia》2002,95(4):1031-6, table of contents
In some patients, cardiopulmonary resuscitation (CPR) can revive spontaneous circulation (ROSC). However, neurological outcome often remains poor. Hypertonic-hyperoncotic solutions (HHS) have been shown to improve microvascular conductivity after regional and global ischemia. We investigated the effect of infusion of HHS in a porcine CPR model. Cardiac arrest was induced by ventricular fibrillation. Advanced cardiac life support was begun after 4 min of nonintervention and 1 min of basic life support. Upon ROSC, the animals randomly received 125 mL of either normal saline (placebo, n = 8) or 7.2% NaCl and 10% hydroxyethyl starch 200,000/0.5 (HHS, n = 7). Myocardial and cerebral damage were assessed by serum concentrations of cardiac troponin I and astroglial protein S-100, respectively, up to 240 min after ROSC. In all animals, the levels of cardiac troponin I and S-100 increased after ROSC (P < 0.01). This increase was significantly blunted in animals that received HHS instead of placebo. The use of HHS in the setting of CPR may provide a new option in reducing cell damage in postischemic myocardial and cerebral tissues. IMPLICATIONS: Infusion of hypertonic-hyperoncotic solutions (HHS) after successful cardiopulmonary resuscitation in pigs significantly reduced the release of cardiac troponin I and cerebral protein S-100, which are sensitive and specific markers of cell damage. Treatment with HHS may provide a new option to improve the outcome of cardiopulmonary resuscitation.  相似文献   
959.
We estimated the predictive power with respect to defibrillation outcome of ventricular fibrillation (VF) mean frequency (FREQ), mean peak-to-trough amplitude (AMPL), and their combination. We examined VF electrocardiogram signals of 64 pigs from 4 different cardiac arrest models with different durations of untreated VF, different durations of cardiopulmonary resuscitation, and use of different drugs (epinephrine, vasopressin, N-nitro-L-arginine methyl ester, or saline placebo). The frequency domain was restricted to the range from 4.33 to 30 Hz. In the 10-s epoch between 20 and 10 s before the first defibrillation shock, FREQ and AMPL were estimated. We introduced the survival index (SI; 0.68 Hz(-1). FREQ + 12.69 mV(-1). AMPL) by use of multiple logistic regression. Kruskal-Wallis nonparametric one-way analysis was used to analyze the different porcine models for significant difference. The variables FREQ, AMPL, and SI were compared with defibrillation outcome by means of univariate logistic regression and receiver operating characteristic curves. SI increased predictive power compared with AMPL or FREQ alone, resulting in 89% sensitivity and 86% specificity. The probabilities of predicting defibrillation outcome for FREQ, AMPL, and SI were 0.85, 0.89 and 0.90, respectively. FREQ, AMPL, and SI values were not sensitive in regard to the four different cardiac arrest models but were significantly different for vasopressin and epinephrine animals. IMPLICATIONS: We present a retrospective data analysis to evaluate the predictive power of different ventricular fibrillation electrocardiogram variables in pigs with respect to defibrillation outcome. We showed that our combination of variables leads to an improved forecast, which may help to reduce harmful unsuccessful defibrillation attempts.  相似文献   
960.
BACKGROUND: Over recent years, heart transplantation (HTX) developed into a successful option for long-term treatment of end-stage heart failure. Ten-year survival ranges between 40% and 50%. Little is known, however, about function and morphology of transplanted hearts during follow-up of more than 10 years. METHODS: In a consecutive cohort of 65 patients (55 male, 54.6 +/- 12.1 years at the time of transplantation), graft function was assessed by color Doppler echocardiography 12.5 +/- 1.4 years after heart transplantation (10 to 15 years). RESULTS: Left atrial and ventricular dimensions were found in a normal range (LA 37.7 +/- 8.9 mm, LV enddiastolic 45.6 +/- 6.4 mm, 30 to 71 mm). Ejection fraction (EF) of 71 +/- 11.7% and a fractional shortening of 35.3 +/- 10.3% presented with normal values. Left ventricular mass (male 263.8 +/- 111.4 g, female 373.0 +/- 181.1 g) was slightly increased resulting in mild hypertrophy in women. Focused on right ventricular morphology, enlargement of both the right atrium and the right ventricle (RA 40.7 +/- 11.8 mm, RV 37.4 +/- 8.3 mm) was observed in the majority of the patients. Tricuspid valve insufficiency (> grade II) was present in 46 of 65 patients; 5 patients had previously undergone tricuspid valve replacement. Atrial filling waves were detectable in only 47 of 65 patients, thus, 28% of patients showed signs of LA-dysfunction. CONCLUSIONS: More than 10 years post-HTX, cardiac grafts were characterized by normal left ventricular dimensions and ejection fraction. LA-dysfunction and RV-enlargement associated with tricuspid insufficiency were frequent findings, however, not associated with clinical signs of congestive heart failure in the majority of patients.  相似文献   
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