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991.
To identify tracheobronchial abnormalities associated with assisted ventilation, 40 infants with respiratory distress syndrome randomized to receive either short-term (48 hours) conventional or high-frequency jet ventilation were studied. Flexible fiberoptic bronchoscopy (n = 13) was performed and/or clinical and radiographic assessments were used to evaluate for laryngeal, tracheal, and bronchial lesions. There was no bronchoscopic evidence of necrotizing tracheobronchitis after either high-frequency jet ventilation (n = 8) or conventional ventilation (n = 5). Laryngotracheomalacia and nodular vocal cords were the most common abnormalities noted, and they occurred with equal frequency in both groups. Study infants who were not bronchoscoped had no clinical or radiographic evidence of tracheal or mainstem bronchial obstruction. One patient did have microscopic evidence of necrotizing tracheobronchitis at autopsy, however. It is concluded that short-term treatment of respiratory distress syndrome with high-frequency jet ventilation may be performed without undue risk of tracheobronchial injury. 相似文献
992.
Decreased ventilation in preterm infants during oral feeding 总被引:7,自引:0,他引:7
As respiratory difficulty may accompany nipple feeding in preterm neonates, we studied the effect of oral feeding on ventilation in 23 preterm infants. The infants composed two groups based on their postconceptional age at the time of study: Group A comprised 12 infants 34 to 35.9 weeks of age, and group B, 11 infants 36 to 38 weeks. Ventilation was measured via a nasal mask pneumotachometer, and sucking pressure via a nipple that also permitted milk delivery; transcutaneous PO2 and PCO2 were continuously monitored. The feeding pattern comprised an initial period of continuous sucking of at least 30 seconds, followed by intermittent sucking bursts for the remainder of the feed. When compared with an initial semi-upright control period, minute ventilation (V1) during continuous sucking fell by 52 +/- 6% (P less than 0.001) and 40 +/- 2% (P less than 0.001) in groups A and B, respectively. This was the result of a decrease in respiratory frequency and tidal volume and was associated with a fall in TcPO2 of 13 +/- 4 mm Hg (P less than 0.01) in group A and 10 +/- 2 mm Hg (P less than 0.01) in group B. During intermittent sucking, V1 and TcPO2 recovered partially only in the more mature infants (group B). At the end of the feed, TcPCO2 have risen by 3 +/- 1 mm Hg (P less than 0.001) in group A and by 2 +/- 2 mm Hg (P less than 0.05) in group B. Thus oral feeding results in an impairment of ventilation during continuous sucking and the subsequent recovery during intermittent sucking is dependent on postconceptional age. 相似文献
993.
Bonanni F Brignone M Garrone A Gobbi M Menardo G Parodi L Venzano C 《Annali italiani di medicina interna : organo ufficiale della Società italiana di medicina interna》2002,17(4):248-251
The aim of the present study was to evaluate the epidemiology of anemias in Internal Medicine Departments. The study involved all patients discharged between May 1 and June 15, 2001 who, at the time of admission, had presented with hemoglobin levels < 12 g%. One thousand and nineteen data collection forms were deemed suitable for analysis and were divided according to the etiology and severity of the anemia. We discovered that simple diagnostic tests (reticulocyte count) were underused, that the majority of anemias were not corrected during hospitalization and that most inpatients of Internal Medicine wards in our Region are elderly (mean age 75 years) and suffer from polypathologies. We believe that further observational studies should be carried out in order to evaluate the progress of patients with anemia and to establish guidelines for the diagnosis and treatment. 相似文献
994.
995.
996.
Role of venous drainage in cerebral arteriovenous malformation surgery,as related to the development of postoperative hyperperfusion injury 总被引:2,自引:0,他引:2
OBJECTIVE: To elucidate the role of venous drainage in cerebral arteriovenous malformation (AVM) surgery, with respect to the development of postoperative hyperperfusion injury. METHODS: For 52 patients with supratentorial AVMs, cortical capillary oxygenation (SaO(2)) was assessed intraoperatively, before and after resection, in the vicinity of the AVMs, by using a microspectrophotometric method. Assessed areas were defined as being related to feeding arteries or draining veins or as distant areas. Patients were divided into three groups on the basis of postoperative angiographic findings, as follows: Group 1, all former draining veins preserved (8 patients); Group 2, > or =1 former draining vein visible (12 patients); Group 3, no former draining veins visible (32 patients). Patients and SaO(2) values were pooled and compared by using paired and unpaired t tests (P < 0.05). Venous circulation times were calculated from digital subtraction angiography films. RESULTS: The postresectional relative increases in SaO(2) values were highest in draining vein areas (+40.8%, compared with +25% in feeder areas and +25.5% in distant areas). Five postoperative hyperemic complications occurred (9.6%), none in Group 1 (with all draining veins preserved), two (16.7%) in Group 2, and three (9.4%) in Group 3 (with all draining veins occluded). The lowest preresectional SaO(2) values (31.7 +/- 6.2%) were measured in the drainer areas of the five patients who subsequently developed hyperperfusion injuries. Among those patients, postresectional increases in SaO(2) values were significantly greater in drainer areas (+167.8%) than in feeder areas (+28.3%) or distant areas (+25.8%). Postoperative venous circulation times in former draining veins in Group 2 were significantly greater than those in Group 1 (8.9 +/- 1.5 s versus 6.3 +/- 0.6 s). Circulation times in normal veins in the five patients with hyperperfusion injury increased from 5.6 +/- 1.0 seconds (preoperatively) to 8.4 +/- 1.9 seconds (postoperatively). CONCLUSION: Postoperative hyperperfusion injury after resection of cerebral AVMs can be explained on the basis of unconstrained arterial inflow into cortical areas, which are rendered hypoxic/ischemic by longstanding preoperative venous hypertension. The risk for postoperative breakthrough complications seems higher in the presence of multiple draining veins, which also participate in the physiological venous drainage system of the ipsilateral hemisphere. 相似文献
997.
A personal technique: mammaplasty with J scar 总被引:2,自引:0,他引:2
Mastopexy and reduction mammaplasty techniques have evolved with time, pursuing the aim of an effective and reliable technique that produces a well-shaped breast and reduces the amount of scarring. The authors believe that the L mammaplasty achieves the best results in terms of a short scar and a good, stable shape. They present their technique of a modified L mammaplasty with a resulting scar in the shape of a J, which implies a central breast resection with the nipple-areola complex transposed on a superior pedicle. The correct execution of the preoperative markings and the shaping of the gland tissue are mandatory to obtaining the desired result. The technique has been used during the past 7 years on 326 patients, providing satisfactory results with short scars and virtually no complications. 相似文献
998.
Neri E Sassi C Massetti M Roviello F Giomarelli P Bizzarri F Scolletta S Setacci C 《Journal of vascular surgery》2002,36(4):738-745
BACKGROUND: In aortic dissection, visceral complications that result from aortic branch compromise have been described extensively, whereas intestinal ischemia not associated with the false lumen anatomy has rarely been discussed. The aim of this report is to identify clinical factors that may contribute to the development of this form of acute mesenteric ischemia, to profile the patients at greatest risk, and to review diagnostic and treatment methods that emerged from our experience. METHODS: With a computerized database, we identified 371 patients who underwent treatment in our institution with a diagnosis of aortic dissection between July 15, 1985, and January 10, 2001. Mesenteric ischemia was present in 73 patients (19%). In 36 patients (9%), bowel ischemia was not associated with a false lumen anatomy or an extension of the dissection process. From a general analysis of the determinants of mesenteric ischemia in aortic dissection, we investigated, with univariate and multivariate analysis, the specific characteristics of these patients with nonocclusive ischemia. A retrospective analysis of the oxygen metabolic profile of patients who underwent operation also was performed. RESULTS: The mortality rate in patients with nonocclusive mesenteric ischemia was 86%; sepsis and multiple organ failure were the causes of death in all nonsurvivors. Surgical treatment was beneficial only in the early phases of the disease. The results of the multivariate analysis showed the multifactorial origin of nonocclusive mesenteric ischemia; cerebral ischemia, thrombosis of the false lumen, severe coagulation disorders, chronic obstructive pulmonary disease, aortic calcinosis, prolonged hypotension, chronic renal insufficiency, and low cardiac output were independent predictors of the condition. In patients who underwent operation, the significant risk factors were severe coagulation disorders, postoperative cerebral ischemia, maximal oxygen extraction rate of more than 0.40, aortic calcinosis, chronic obstructive pulmonary disease, thrombosis of the false lumen, inotropic support, and chronic renal insufficiency. An oxygen extraction rate of more than 0.4 at 6 hours after operation was found to be an index of intestinal damage sufficient to initiate an evaluation for visceral ischemia. Significant differences with occlusive ischemia also were evidenced with this study. CONCLUSION: In aortic dissection, nonocclusive mesenteric ischemia shows some unique clinical and individual predisposing factors. Most instrumental investigations are of poor diagnostic value, and prognosis is poor, especially when mesenteric gangrene had already taken place. Prevention can be exercised only with a heightening of our awareness of this condition and with timely correction of metabolic disturbances. In suspected cases, an aggressive surgical attitude may represent the only means for reducing mortality. 相似文献
999.
Training period in laparoscopic colorectal surgery 总被引:7,自引:0,他引:7
Braga M Vignali A Zuliani W Radaelli G Gianotti L Toussoun G Carlo V 《Surgical endoscopy》2002,16(1):31-35
BACKGROUND: Thorough training is essential to the success of colorectal laparoscopic surgery (LPS). The aim of this study was to evaluate the results of a 3-month training period in LPS. METHODS: Before beginning the study, the surgical team attended several courses of LPS and spent a long time working at a large animal facility to perfect laparoscopic techniques. Twenty-six consecutive patients underwent LPS in a 3-month training period. Controls (n = 26) who underwent open colorectal surgery (LPT) were selected to match the LPS patients for age, gender, primary disease, type of surgery, comorbidity, and nutritional status. RESULTS: Conversion to open surgery was necessary in one patient (3.8%). The operative time was 1 h longer for LPS than LPT (p < 0.001). The mean number of lymph nodes harvested was 17 in LPS and 18 in LPT (p = 0.76). The first flatus (p < 0.02) and bowel movement (p < 0.002) occurred earlier in the LPS group. The postoperative infection rate was 11.5% for LPS and 19.2% for LPT (p = 0.33). Two anastomotic leaks occurred in each group. The mean postoperative hospital stay was 9.6 days (standard deviation [SD], 2.6) for LPS and 11.0 days (SD, 5.2) for LPT (p = 0.68). Recovery of postoperative physical performance and social life occurred earlier in the LPS than the LPT group (p < 0.001). At 1-year follow-up, no difference was found in terms of cancer recurrence or long-term complications. CONCLUSION: Oncologic results and postoperative morbidity were comparable for LPS and LPT. LPS allows a faster postoperative recovery. 相似文献
1000.
Pasqual E Bertolissi F Grimaldi F Beltrami CA Scott CA Bacchetti S Waclaw BU Cagol PP 《Surgery today》2002,32(6):563-565
Adrenal epithelioid angiosarcoma is an extremely rare tumor. Even if such tumors are very aggressive, a long survival may
occasionally be observed after an adrenal ectomy. A 70-year-old woman suffering from persistent right flank pain showed a
5-cm right adrenal mass plus a 2-cm liver mass at the radiologic workup, and both were suspected of being malignant. No adrenal
hypersecretion was demonstrated. During an explorative median laparotomy the right adrenal gland with the whole periadrenal
tissue and locoregional lymph nodes was removed. A histological examination revealed an adrenal angiosarcoma. The resection
margin was tumor-free with no lymph node infiltration. The liver mass turned out to be a cistobiliary adenoma. Since no distant
metastases were observed, no adjuvant chemotherapy was performed. After an 18-month follow-up the patient is still well with
no sign of a relapse. When this rare adrenal tumor is encountered and curative treatment is attempted initially extensive
surgical procedures are essential.
Received: April 16, 2001 / Accepted: November 20, 2001 相似文献