PubMed Health⌕ Search

Biomedical subjects

Dawei Zhang

Publications and source records attributed to Dawei Zhang.

23 records · Page 2Linked to original sources

[Management of perioperative respiratory problems in patients with tumor of trachea or carina].

OBJECTIVE: To summarise and analyse the experience and methods of managing the perioperative respiratory problems in patients with tumor of trachea or carina surgically treated during the last decade, and the ways of preventing severe postoperative respiratory complications in the future. METHODS: Thirty-eight patients with tumor of trachea or carina surgically treated from 1991 to 2000 by different modes of tracheobronchial plastic surgery were retrospectively studied to summarise and analyse the changes in preoperative pulmonary function, postoperative complications and the management of perioperative respiratory problems. RESULTS: Out of 38 patients, 29 (76.3%) gave abnormal results to preoperative pulmonary function tests. 55.3% (21/38) of the whole series developed 45 postoperative complications with respiratory complications as the major one (80.0%). Seventeen patients who had undergone carinal pneumonectomy or carinal resection plus reconstruction gave far more complications (28 complications) than the remaining 21 patients treated by other modes of surgery (17 complications). Four patients died of postoperative complications with a mortality rate of 10.5%. CONCLUSION: Patients treated with carinal pneumonectomy or carinal resection plus reconstruction give much more complications than patients treated by any other modes of large airway surgery. Fiberoptic bronchoscopic (FOB) guided intubation, precise surgical treatment, postoperative mechanical ventilation support, use of effective antibiotics and sufficient nutritional support are important for a successful management of these patients.

Adolescent↗

Diagnosis and surgical treatment of esophageal leiomyoma.

OBJECTIVE: To study the characteristics of diagnosis and surgical treatment of esophageal leiomyoma. METHODS: Preoperative radiology, esophagoscopy and results of surgical treatment were retrospectively analyzed in 141 patients with esophageal leiomyoma. RESULTS: Dysphagia (64.5%) and chest or epigastric pain (20.6%) were the most common presenting symptoms with a mean duration of 15.7 months. Eleven patients had been misdiagnosed as malignant esophageal disease, mediastinal or retroperitoneal tumor before operation. Thirteen patents received partial esophageal resection, including 2 patients with gigantic tumor, 3 still misdiagnosed as malignancy in the operation theater and 8 accompanied with esophageal or gastric cardiac carcinoma. 128 patients were treated with tumor removal only, among whom the esophageal mucosa was ruptured and sutured in 13 patents. The tumor was single in 130 patients and multiple in 11 patients. The tumor shape was either oval, horseshoe-or ginger-like. Tumor surrounded the esophagus less than half circumference in 75 patients, more than half in 59 patients and involved the whole circumference in 7 patients. The tumor was polypoid and intraluminal in one patient. It was extraluminal in 2 patients and was intramural in all the others. The morbidity and 30-day mortality rates were 3.6% and 0%. CONCLUSION: Preoperative differentiation of esophageal leiomyoma is important for it may be misdiagnosed as esophageal malignant disease or mediastinal tumor. Tumor removal only is indicated if possible. Biopsy is inadvisable if leiomyoma has been suspected by esophagoscopy. The incidence of esophageal carcinoma complicating esophageal leiomyoma is high, of which the reason needs further study.

Adolescent↗

Versatile Synthesis of Dihydroquinolines and Quinoline Quinones Using Cyclobutenediones. Construction of the Pyridoacridine Ring System.

1-BOC-2-lithio-1,4-dihydropyridines were condensed with 3,4-disubstituted cyclobutenediones to produce 1,2-adducts. Neat thermolysis under oxygen-free conditions produced substituted 1,4-dihydroquinoline hydroquinones in which the tert-butoxy residue of the BOC group was displaced by a phenolic residue, generating an oxazolone ring that functioned to protect both rings of the dihydroquinoline hydroquinone from untimely oxidation. Oxidative aromatization with concomitant loss of the oxazolone ring was achieved using 2 equiv of o-chloranil in acetic acid and provided substituted quinoline quinones in good yields. By use of this strategy, a concise synthesis of the pyridoacridine ring system was achieved.

Journal Article↗