BACKGROUND: Oxygen-derived free radicals are known to contribute to tissue injury during myocardial ischemia and reperfusion. Recent in vitro studies have shown that propofol has potent antioxidant properties. The present study was aimed to investigate the effects of propofol on recovery of mechanical and coronary endothelial function in a myocardial stunning model. METHODS: Thirty-five dogs were acutely instrumented under halothane anesthesia to measure aortic and left ventricular pressure, pulmonary and left anterior descending coronary artery (LAD) flow, and subendocardial segment length. After completion of the surgery, halothane was replaced by fentanyl- midazolam. Animals were then subjected to 15 min of LAD occlusion and 3 hrs of reperfusion under either intracoronary (i.c.) propofol (5 microgram/mL, n=11; 20 microgramg/mL LAD flow, n=12) or vehicle (saline, n=12) for 1 hr beginning 30 min before LAD occlusion. Percent segment shortening (%SS) and the slope of the preload recruitable stroke work (Mw), as an index of regional myocardial contractility, and peak lengthening rate (dL/dtmax) and percent post-systolic shortening (%PSS), as an index of regional diastolic function, were evaluated. Coronary endothelial function was assessed by examining LAD flow response to i.c. acetylcholine (ACh, 1 microgram over I min) and i.c. sodium nitroprusside (SNP, 20 microgram over I min). The myocardial content of malondialdehyde (MDA) from LAD area was measured to evaluate lipid peroxidation. RESULTS: Despite equally severe ischemic dysfunction during LAD occlusion, recovery of %SS was significantly improved during reperfusion by either dose of propofol compared to controls. However, Mw recovered to the baseline within 60 min of reperfusion in all three groups. In addition, propofol-treated dogs showed better recovery of both indices of regional diastolic function (dL/dtmax and %PSS) as compared to controls. Ischemia-reperfusion similarly attenuated the increases in the LAD flow by ACh in all the groups, whereas it had no significant effect on these increases in LAD flow by SNP. The increase in MDA induced by ischemia and reperfusion was significantly suppressed by either dose of propofol. CONCLUSIONS: The results indicate that propofol attenuates mechanical but not coronary endothelial dysfunction in postischemic, reperfused myocardium in an open-chest canine model. The protective action of propofol against mechanical dysfunction is probably due to its effect to reduce lipid peroxidation.
Acetylcholine ; Anesthesia ; Animals ; Coronary Vessels ; Dogs* ; Endothelium* ; Free Radicals ; Halothane ; Ischemia ; Lipid Peroxidation ; Malondialdehyde ; Midazolam ; Myocardial Ischemia ; Myocardial Stunning* ; Myocardium ; Nitroprusside ; Propofol* ; Reperfusion ; Stroke ; Ventricular Pressure

No Abstract available.
Anesthetics* ; Reperfusion Injury* ; Reperfusion*

Succinylcholine (Sch) has long been used to facilitate laryngoscopy and endotracheal intubation for general anesthesia, because of a rapid onset of intense but brief paralysis. However, exaggerated potassium (K+) release following Sch, sufficient to cause ventricular dysrhythmias and cardiac arrest, has sporadically been reported in susceptible conditions, including spinal cord injury, severe burn, massive trauma and neuromuscular disorder. And diazepam has been shown to attenuate the increase in serum K+ following Sch administration. The purpose of this study was to assess the effect of Sch on serum K+ in patients with spinal cord lesions, and to assess the effect of pretreatment with diazepam (0.05 mg/kg IV) on potassium flux. The results were as follows: 1) Baseline K+ values were not significantly different among the groups. 2) The time to peak increases in K+ was 3 minutes following Sch in all groups. 3) The magnitude of maximum increases in K' following Sch were 0.32 Eq/l, 0.63 mEq/l, 0.06 mEq/I and 1,10 mEq/I in group 1, group 2A, group 2B, and group 3, respectively. 4) Diazepam pretreatment attenuated the increases in K+ following Sch. From the above results, it can be concluded that Sch may safely be used to facilitate intubation in paraplegic patients, provided that they are normokalemic and pretreated with diazepam.
Anesthesia, General ; Burns ; Diazepam ; Heart Arrest ; Humans ; Hypnotics and Sedatives ; Intubation ; Intubation, Intratracheal ; Laryngoscopy ; Paralysis ; Potassium* ; Spinal Cord Injuries ; Spinal Cord* ; Succinylcholine*

BACKGROUND: The influenza is a contagious respiratory illness caused by influenza viruses. The primary target groups recommended for annual vaccination are healthcare workers and households which have frequent contact with persons at high risk and can transmit influenza to those persons at high risk. Members of these groups should be vaccinated against the flu so that they can avoid getting infected with continuously mutating influenza viruses. We assessed healthcare workers' knowledge and attitudes regarding influenza vaccination in order to help promote the vaccination rate. METHODS: This survey was carried out in two hospitals affiliated with the Catholic University School of Medicine, from December 2004 to January 2005. Of the 3,023 questionnaires distributed, 2,023 could be evaluated. RESULTS: The most frequently cited reason for receiving influenza vaccine was self-protection against influenza (55.4%). The most common reasons for not receiving influenza vaccine are personal health problems such as concurrent flu, pregnancy or breast-feeding (29.2%). There is no significant difference in the frequency of side effect between two groups receiving and not receiving vaccine. The most frequent side effect of influenza vaccination is flu-like syndrome; People receiving vaccine have more significant knowledge than those people not receiving vaccine about efficacy of flu vaccination, risk of influenza infection of healthcare workers and their need of flu vaccination. CONCLUSION: In order to promote the vaccination rate, education targeting people at high risk need to keep continuous and facilitate access to vaccination.
Delivery of Health Care* ; Education ; Family Characteristics ; Humans ; Influenza Vaccines ; Influenza, Human* ; Orthomyxoviridae ; Pregnancy ; Vaccination* ; Surveys and Questionnaires

Perioperative myocardial infarction is a major cause of morbidity and mortality in patients who undergo non-cardiac surgery, while an increasing number of patients with a coronary artery disease are presenting for surgery. In order to cope with this problem, one should first evaluate risk factors of these complications, and then manage the patient at risk to reduce or eliminate the risk factors. Risk assessment evaluates patients' co-morbidities and exercise tolerance, as well as the type of surgery to be performed, to determine the overall risk of perioperative cardiac complications. Previous or current cardiac disease, diabetes, and renal insufficiency all confer higher risks for perioperative cardiac complications. Poor exercise tolerance and high-risk surgical procedures (e.g., vascular, prolonged thoracic, or abdominal operations) also predict worse perioperative outcomes. Stress testing should be reserved for patients at moderate to high risk undergoing moderate- or high-risk surgery and those who have poor exercise capacity. After the assessment of the risk of cardiac complications, one should take measures to reduce it, including medical therapy and coronary intervention. Medical therapy using beta blockers, statins, and alpha-2 agonists may be effective to reduce perioperative risk and to obviate the need for more invasive procedures in high-risk patients. Coronary intervention should be performed for those patients who are indicated independent of the non-cardiac surgery. There appears to be no single best myocardium-protective anesthetic management, and therefore, the choice of anesthesia and intraoperative monitors is left at the discretion of the anesthesia care team.
Anesthesia* ; Coronary Artery Disease ; Exercise Test ; Exercise Tolerance ; Heart Diseases* ; Humans ; Hydroxymethylglutaryl-CoA Reductase Inhibitors ; Mortality ; Myocardial Infarction ; Renal Insufficiency ; Risk Assessment ; Risk Factors

No abstract available.

No abstract available.
Hemodynamics* ; Nitroprusside*

BACKGROUND: Video-assisted thoracic surgical procedure via thoracoscopy has recently gained popularity, as it avoids a thoracotomy, reducing intraoperative blood loss, postoperative pain, respiratory dysfunction and hospital stay. However, to visualize adequately the intrathoracic structures, creation of artificial pneumothorax by carbon dioxide insufflation during thoracoscopy would cause significant hemodynamic compromise. The aim of this study was to evaluate the effect of CO2 insufflation into the pleural cavity on the hemodynamics and the arterial blood gas tension under general anesthesia. METHODS: Twenty-five patients, after intubation with single lumen endotracheal tube, underwent enflurane (1~2%) and N2O-O2 (1:1) general anesthesia. Before placement of a thoracoscope, the baseline mean arterial pressure and heart rate were obtained. Measurements were taken at 5, 10, and 20 min. after the beginning of carbon dioxide insufflation (3~5 mmHg) and 10 min. after gas evacuation. Blood gas analyses were done before, during CO2 insufflation and after CO2 evacuation. Data were analyzed using Student t-test. RESULTS: Positive-pressure CO2 insufflation (3~5 mmHg) caused a decrease of mean arterial pressure (5~7%) and an increase of airway pressure (1.5 times) and heart rate (13~20%) throughout the gas insufflation period (p<0.05). Blood gas analyses revealed no significant change. CONCLUSIONS: These results suggest that low CO2 insufflation pressures (3~5 mmHg) may cause cardiovascular depression during thoracoscopy. Therefore careful monitorings should be done during this procedure.
Anesthesia, General* ; Arterial Pressure ; Blood Gas Analysis ; Carbon Dioxide* ; Carbon* ; Depression ; Enflurane ; Heart Rate ; Hemodynamics* ; Humans ; Insufflation* ; Intubation ; Length of Stay ; Pleural Cavity ; Pneumothorax, Artificial ; Postoperative Hemorrhage ; Thoracic Surgical Procedures ; Thoracoscopes ; Thoracoscopy* ; Thoracotomy

In this paper, we review the use of hypofractionated radiotherapy for gastrointestinal malignancies, focusing on primary and metastatic liver cancer, and recurrent rectal cancer. Technological advancements in radiotherapy have facilitated the direct delivery of high-dose radiation to tumors, while limiting normal tissue exposure, supporting the use of hypofractionation. Hypofractionated radiotherapy is particularly effective for primary and metastatic liver cancer where high-dose irradiation is crucial to achieve effective local control. For recurrent rectal cancer, the use of stereotactic body radiotherapy offers a promising approach for re-irradiation, balancing efficacy and safety in patients who have been administered previous pelvic radiotherapy and in whom salvage surgery is not applicable. Nevertheless, the potential for radiation-induced liver disease and gastrointestinal complications presents challenges when applying hypofractionation to gastrointestinal organs. Given the lack of universal consensus on hypofractionation regimens and the dose constraints for primary and metastatic liver cancer, as well as for recurrent rectal cancer, this review aims to facilitate clinical decision-making by pointing to potential regimens and dose constraints, underpinned by a comprehensive review of existing clinical studies and guidelines.

Hypofractionated radiotherapy (RT) has become a trend in the modern era, as advances in RT techniques, including intensity-modulated RT and image-guided RT, enable the precise and safe delivery of high-dose radiation. Hypofractionated RT offers convenience and can reduce the financial burden on patients by decreasing the number of fractions. Furthermore, hypofractionated RT is potentially more beneficial for tumors with a low α/β ratio compared with conventional fractionation RT. Therefore, hypofractionated RT has been investigated for various primary cancers and has gained status as a standard treatment recommended in the guidelines. In genitourinary (GU) cancer, especially prostate cancer, the efficacy, and safety of various hypofractionated dose schemes have been evaluated in numerous prospective clinical studies, establishing the standard hypofractionated RT regimen. Hypofractionated RT has also been explored for gynecological (GY) cancer, yielding relevant evidence in recent years. In this review, we aimed to summarize the representative evidence and current trends in clinical studies on hypofractionated RT for GU and GY cancers addressing several key questions. In addition, the objective is to offer suggestions for the available dose regimens for hypofractionated RT by reviewing protocols from previous clinical studies.