(1/805) Peri-operative changes in echocardiographic measurements and plasma atrial and brain natriuretic peptide concentrations in 3 dogs with patent ductus arteriosus.

Peri-operative changes in echocardiographic measurements and plasma levels of atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) were investigated for 1 month in 3 dogs with patent ductus arteriosus (PDA). Post-operative left ventricular end-diastolic dimention and fractional shortening decreased in all cases. Pre-operatively increased plasma ANP concentrations reduced dramatically after the operation. Peri-operative changes in plasma BNP levels had slightly S-shaped curves in all cases. These observations suggest that post-operative responsiveness of ANP and cardiac function are rapid in comparison with cardiac morphological changes, and BNP has a different pathophysiological significance from ANP in dogs with PDA.  (+info)

(2/805) Measurement of peripheral tissue thickness by ultrasound during the perioperative period.

We have studied changes in peripheral tissue thickness with a novel hand-held ultrasound device during the perioperative course of 60 healthy surgical patients in three different intraoperative body positions. The nil-by-mouth period led to a significant decrease in forehead tissue thickness. Standardized infusion therapy with Ringer's solution at a rate of 8 ml kg-1 h-1 resulted in a gradual increase in tissue thickness, which was significantly different from preoperative baseline values after 90 min. Packed cell volume decreased significantly after the start of infusion and remained low over the rest of the observation time. Different body positions did not influence changes in tissue thickness. We conclude that changes in perioperative tissue thickness in healthy patients can be detected easily by ultrasound, independent of body position. This method may prove useful for the non-invasive assessment of fluid balance state.  (+info)

(3/805) The effect of bisoprolol on perioperative mortality and myocardial infarction in high-risk patients undergoing vascular surgery. Dutch Echocardiographic Cardiac Risk Evaluation Applying Stress Echocardiography Study Group.

BACKGROUND: Cardiovascular complications are the most important causes of perioperative morbidity and mortality among patients undergoing major vascular surgery. METHODS: We performed a randomized, multicenter trial to assess the effect of perioperative blockade of beta-adrenergic receptors on the incidence of death from cardiac causes and nonfatal myocardial infarction within 30 days after major vascular surgery in patients at high risk for these events. High-risk patients were identified by the presence of both clinical risk factors and positive results on dobutamine echocardiography. Eligible patients were randomly assigned to receive standard perioperative care or standard care plus perioperative beta-blockade with bisoprolol. RESULTS: A total of 1351 patients were screened, and 846 were found to have one or more cardiac risk factors. Of these 846 patients, 173 had positive results on dobutamine echocardiography. Fifty-nine patients were randomly assigned to receive bisoprolol, and 53 to receive standard care. Fifty-three patients were excluded from randomization because they were already taking a beta-blocker, and eight were excluded because they had extensive wall-motion abnormalities either at rest or during stress testing. Two patients in the bisoprolol group died of cardiac causes (3.4 percent), as compared with nine patients in the standard-care group (17 percent, P=0.02). Nonfatal myocardial infarction occurred in nine patients given standard care only (17 percent) and in none of those given standard care plus bisoprolol (P<0.001). Thus, the primary study end point of death from cardiac causes or nonfatal myocardial infarction occurred in 2 patients in the bisoprolol group (3.4 percent) and 18 patients in the standard-care group (34 percent, P<0.001). CONCLUSIONS: Bisoprolol reduces the perioperative incidence of death from cardiac causes and nonfatal myocardial infarction in high-risk patients who are undergoing major vascular surgery.  (+info)

(4/805) Supplemental perioperative oxygen to reduce the incidence of surgical-wound infection.

BACKGROUND: Destruction by oxidation, or oxidative killing, is the most important defense against surgical pathogens and depends on the partial pressure of oxygen in contaminated tissue. An easy method of improving oxygen tension in adequately perfused tissue is to increase the concentration of inspired oxygen. We therefore tested the hypothesis that the supplemental administration of oxygen during the perioperative period decreases the incidence of wound infection. METHODS: We randomly assigned 500 patients undergoing colorectal resection to receive 30 percent or 80 percent inspired oxygen during the operation and for two hours afterward. Anesthetic treatment was standardized, and all patients received prophylactic antibiotic therapy. With use of a double-blind protocol, wounds were evaluated daily until the patient was discharged and then at a clinic visit two weeks after surgery. We considered wounds with culture-positive pus to be infected. The timing of suture removal and the date of discharge were determined by the surgeon, who did not know the patient's treatment-group assignment. RESULTS: Arterial oxygen saturation was normal in both groups; however, the arterial and subcutaneous partial pressure of oxygen was significantly higher in the patients given 80 percent oxygen than in those given 30 percent oxygen. Among the 250 patients who received 80 percent oxygen, 13 (5.2 percent; 95 percent confidence interval, 2.4 to 8.0 percent) had surgical-wound infections, as compared with 28 of the 250 patients given 30 percent oxygen (11.2 percent; 95 percent confidence interval, 7.3 to 15.1 percent; P=0.01). The absolute difference between groups was 6.0 percent (95 percent confidence interval, 1.2 to 10.8 percent). The duration of hospitalization was similar in the two groups. CONCLUSIONS: The perioperative administration of supplemental oxygen is a practical method of reducing the incidence of surgical-wound infections.  (+info)

(5/805) High local recurrence risk after breast-conserving therapy in node-negative premenopausal breast cancer patients is greatly reduced by one course of perioperative chemotherapy: A European Organization for Research and Treatment of Cancer Breast Cancer Cooperative Group Study.

PURPOSE: Patients with invasive breast cancer may develop a local recurrence (LR) after breast-conserving therapy (BCT). Younger age has been found to be an independent risk factor for LR. Within a group of premenopausal node-negative breast cancer patients, we studied risk factors for LR and the effect of perioperative chemotherapy (PeCT) on LR. PATIENTS AND METHODS: The European Organization for Research and Treatment of Cancer (EORTC) conducted a randomized trial (EORTC 10854) to compare surgery followed by one course of PeCT (fluorouracil, doxorubicin, and cyclophosphamide) with surgery alone. From patients treated on this trial, we selected premenopausal patients with node-negative breast cancer who were treated with BCT to examine whether histologic characteristics and the expression of various proteins (estrogen receptor, progesterone receptor, p53, Ki-67, bcl-2, CD31, c-erbB-2/neu) are risk factors for subsequent LR. Also, the effect of one course of PeCT on the LR risk (LRR) was studied. RESULTS: Using multivariate analysis, age younger than 43 years (relative risk [RR], 2.75; 95% confidence interval [CI], 1.46 to 5.18; P =.002), multifocal growth (RR, 3.34; 95% CI, 1.27 to 8.77; P =.014), and elevated levels of p53 (RR, 2. 14; 95% CI, 1.13 to 4.05; P =.02) were associated with higher LRR. Also, PeCT was found to reduce LRR by more than 50% (RR, 0.47; 95% CI, 0.25 to 0.86; P =.02). Patients younger than 43 years who received PeCT achieved similar LR rates as those of patients younger than 43 years who were treated with BCT alone. CONCLUSION: In premenopausal node-negative patients, age younger than 43 years is the most important risk factor for LR after BCT; this risk is greatly reduced by one course of PeCT. The main reason for administering systemic adjuvant treatment is to improve overall survival. The important reduction of LR after BCT is an additional reason for considering systemic treatment in young node-negative patients with breast cancer.  (+info)

(6/805) The oxygen trail: measurement.

Tissue hypoxia may be defined as abnormal oxygen utilization such that cells are experiencing anaerobic metabolism. Tissue hypoxia can be defined biochemically by low levels of ATP, high levels of NADH, or decreased oxidized cytochrome aa3. It is possible to measure these biochemical markers in the laboratory setting with, for example, nuclear magnetic resonance spectroscopy. However, this is not as yet a clinical option. There is no 'gold standard' for the diagnosis of clinical hypoxia. We can detect the gross consequences of tissue hypoxia, such as organ dysfunction and metabolic markers of anaerobic metabolism (e.g. lactic acidosis). We have also become familiar with the measurement of both global and regional oxygen dispatch and consumption. However, organ dysfunction and metabolic acidosis consistent with established tissue hypoxia commonly exists in the presence of normal and even supra normal global measures of oxygen dispatch and consumption. Therefore, we should ideally make measurements at the end of the oxygen trail, i.e. cellular oxygen delivery and effective utilization.  (+info)

(7/805) Comparison of two different approaches for internal jugular vein cannulation in surgical patients.

We compared the anterior approaches of internal jugular venous cannulation in 200 surgical patients, vis-a-vis the ease of cannulation and threading, number of attempts required and the incidence of complications following each route. The technique of posterior approach used in this study was found to have a higher rate of success in cannulation and lower rate of complication such as carotid puncture. The posterior approach was also a safe alternate route in obese or short necked patients.  (+info)

(8/805) Perioperative blood transfusion and albumin administration are independent risk factors for the development of postoperative infections after colorectal surgery.

OBJECTIVES: To determine whether transfused colorectal surgery patients were at increased risk for postoperative infections in a tertiary care teaching hospital and whether transfusion alone was the only significant risk factor. DESIGN: A retrospective study. SETTING: A single tertiary care teaching hospital. PATIENTS: All patients admitted to St. Boniface General Hospital, Winnipeg, for colorectal surgery during the period Apr. 1, 1995, through Mar. 31, 1996, were studied (N = 154). RESULTS: The overall infection rate was 17%: nontransfused patients, 13%, and transfused patients, 28% (p < 0.038). Patients who received albumin perioperatively had a significantly higher infection rate (38%) than those who did not (13%) (p < 0.001). Stepwise logistic regression analysis identified transfusion and albumin administration as the only independent risk factors for postoperative infection. CONCLUSION: Perioperative transfusion or albumin administration significantly increases the risk of postoperative infection in colorectal surgery patients.  (+info)