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Kuang-Cheng Chan

Publications and source records attributed to Kuang-Cheng Chan.

5 recordsLinked to original sources

Oxidative stress during 1-lung ventilation.

OBJECTIVES: Resuming 2-lung ventilation from 1-lung ventilation might induce a re-expansion and reoxygenation effect. The oxidative stress during 1-lung ventilation/2-lung ventilation has not been studied, although severe complications, such as re-expansion pulmonary edema, were reported. Reactive oxygen species production and total antioxidant status assay levels were measured in this study during 1-lung ventilation/2-lung ventilation. The effects on extravascular lung water, cardiac output, and intrathoracic blood volume were also studied by using the Pulsion PiCCO system. METHODS: Twenty patients undergoing 1-lung ventilation/2-lung ventilation (>60 minutes) for video-assisted thoracoscopic surgery with minimal lung injuries were included in this study. Reactive oxygen species production was measured by means of lucigenin (detecting superoxide mainly) and luminol (detecting H2O2 and HOCl mainly) chemiluminescence. Reactive oxygen species production, total antioxidant status assay (by using the Randox TAS kit), extravascular lung water, cardiac output, and intrathoracic blood volume values were measured before 1-lung ventilation (T1), before resuming 2-lung ventilation (T2), 5 minutes after 2-lung ventilation (T3), and 30 minutes after 2-lung ventilation (T4). RESULTS: One-lung ventilation time was 118 +/- 33 minutes. Lucigenin chemiluminescence (but not luminol chemiluminescence) increased significantly at T3 and T4. Total antioxidant status decreased nonsignificantly. Extravascular lung water, intrathoracic blood volume, and permeability index values changed nonsignificantly after 2-lung ventilation. Cardiac output increased significantly at T4, and there is a negative correlation between cardiac output and extravascular lung water (r = -0.431, P < .005). CONCLUSIONS: Resuming 2-lung ventilation induces a massive superoxide production. Comparable extravascular lung water and intrathoracic blood volume and a nonsignificant decrease of total antioxidant status indicate adequate antioxidant capacity to counteract it. Severe oxidative injuries after 1-lung ventilation/2-lung ventilation should be considered in patients without adequate antioxidative capacity, such as those with cancer and trauma.

Adult↗

General anesthetic management for diagnostic splenectomy in a patient with paraneoplastic pemphigus.

Paraneoplastic pemphigus (PNP) is an autoantibody-mediated mucocutaneous blistering disease that often occurs with confirmed or occult malignancy. It is often accompanied by extensive eruption of respiratory mucosa and can lead to respiratory failure. The indications for anesthetic management in patients with PNP are rare due to the high risk of generating further eruption of respiratory mucosa during intubation, with potentially disastrous consequences. We report the anesthetic management in a 43-year-old woman with PNP scheduled for diagnostic splenectomy. The surgery was postponed due to persistent hoarseness, diffuse oral-pharyngeal mucositis, and laryngeal erosion. Methylprednisolone 40 mg 3 times daily was prescribed for controlling the mucosa lesions. Two weeks later, after the improvement of mucosal lesions, direct laryngoscopic intubation and the scheduled splenectomy were performed under general anesthesia. Pathology of the spleen showed low-grade B-cell lymphoma had induced PNP. Flexible fiberoptic bronchoscopic examination revealed neither bleeding nor bullae formation in the trachea either immediately after intubation or before extubation. The tracheal mucosa is highly susceptible to mechanical stimulation with direct laryngoscopic intubation. Cuff inflation and positive pressure ventilation, awareness of the disease characteristics of PNP, a sufficient course of steroid therapy beforehand, and adequate mucosal protection are essential to the uneventful anesthetic management of the patient with PNP involving the respiratory tract mucosa.

Adult↗

The effect of IVPCA morphine on post-hysterectomy bowel function.

BACKGROUND: Although morphine has been shown to induce bowel dysfunction in a dose-dependent fashion, in most relevant studies it was investigated in single bolus injection. Recently, intravenous morphine via patient-controlled analgesia (IVPCA) has been widely used to provide analgesia by divided bolus doses on patients' demand with satisfactory effects. This approach, by reducing the peak serum surge, largely resembles the pharmacokinetic and pharmacodynamic advantage of continuous infusion. There is yet no report on the investigation of its effect on post-operative bowel dysfunction. METHODS: Fifty-one women who underwent abdominal total hysterectomy (ATH) due to uterine myoma were enrolled to investigate the association between the doses of morphine consumption by PCA and the time of first passage of flatus. In all patients morphine was administered intravenously via a PCA pump immediately after recovery from general anesthesia. RESULTS: We found that 49 out of 51 patients (96%) exhibited mild pain with IVPCA morphine. They had consumed an average dose of 16.9 mg morphine (range, 0-46 mg) upon the first passage of flatus which occurred 2036.4 min (average) post-operatively. There was no correlation between the dose of morphine and the time of first passage of flatus (r = 0.053, P > 0.05). CONCLUSIONS: The absence of suppression of bowel movement by IVPCA morphine for post-operative pain control suggests that favorable pharmacokinetic profile of IVPCA can help reduce the morphine-induced bowel dysfunction at its therapeutic level.

Adult↗

Transesophageal echocardiographic monitoring of critical left ventricular outflow tract obstruction following mitral xenograft replacement--a case report.

Left ventricular outflow tract obstruction (LVOTO) is a critical complication after mitral bioprosthesis. Intraoperative transesophageal echocardiographic (TEE) monitoring enables early diagnosis and guides prompt subsequent treatment. Here we report a case of mitral heart disease who developed critical LVOTO following mitral xenograft replacement. The values of intraoperative TEE in the disclosure of the LVOTO and its facilitation of successful management are discussed.

Animals↗