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Dr Gerald A. Maccioli MD Daniel R. Kuni MS George Silvay MD PhD John M. Evans MB Jerry M. Calkins MD PhD Joel A. Kaplan MD 《Journal of clinical monitoring and computing》1988,4(4):247-255
A multiple-center study was performed to determine the relationship between lower esophageal contractility, clinical signs, and anesthetic concentration as expressed by minimum alveolar concentration (MAC). One hundred four American Society of Anesthesiologists Class I through III patients were exposed to isoflurane (with and without nitrous oxide) or halothane in concentrations of 0.5, 1.0, and 1.5 MAC. Heart rate and systolic blood pressure were continuously monitored. Both the amplitude and frequency of spontaneous and provoked lower esophageal contractions were measured in situ by using a 24-F probe equipped with provoking and measuring balloons. Combined results demonstrated statistically significant correlations (P<0.001) between lower esophageal contractility and MAC. Spontaneous lower esophageal contractions decreased from 1.10±0.12 (SEM) contractions per minute (0.5 MAC) to 0.42±0.05 (1 MAC) to 0.18±0.05 (1.5 MAC). Provoked lower esophageal contractility values decreased from 45±4 mm Hg (0.5 MAC) to 29±3 (1 MAC) to 19±2 (1.5 MAC). Heart rate changes did not correlate with MAC, and systolic blood pressure correlated in only one of three centers. Intracenter and intercenter analyses failed to demonstrate a significant relationship between lower esophageal contractility and heart rate or systolic blood pressure. No intracenter differences in either amplitude or frequency of lower esophageal contractions were observed, despite differences in volatile agents, induction techniques and agents, patient populations, and duration of anesthesia. Our studies indicate that lower esophageal contractility may be an indicator of anesthetic depth as reflected by MAC, but further studies are needed to quantify the effects of surgical stimulus, intravenous anesthetics, vasodilators, anticholinergics, calcium channel blockers, beta-adrenergic agonists, and the presence of a nasogastric tube. 相似文献
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C Sekar S Rajasekaran Rajesh Kannan Shashidhar Reddy T Ajoy Prasad Shetty Yogesh K Pithwa 《The spine journal》2004,4(3):261-264
BACKGROUND CONTEXT: Administration of analgesic medication, before the actual onset of painful stimulus, is more effective than that after the onset of painful stimulus. This is the principle of preemptive analgesia. Although it is often considered superior to other forms of analgesia, its role in postoperative pain relief after lumbosacral spinal surgery has not been fully investigated. PURPOSE: To analyze the efficacy of preemptive analgesia with a single caudal epidural injection for patients undergoing surgeries on the lumbosacral spine by the posterior approach. STUDY DESIGN/SETTING: Randomized, double-blinded and controlled clinical trial. PATIENT SAMPLE: Eighty-two patients who underwent discectomy in the lumbosacral spine by the posterior approach, with or without instrumentation, were randomized to the control group (n=40) and to the study group (n=42). METHODS: Patients in control group received a single caudal epidural injection of 20 ml of normal saline. Patients in study group received a single caudal epidural injection of 20 ml containing bupivacaine and tramadol as the active agents. The time interval between this injection and the surgical incision was never less than 20 minutes in either of the groups. This facilitated enough time for the drug to get fixed to the nerve roots, leading to effective preemptive analgesia. OUTCOME MEASURES: Patients were monitored for postoperative pain immediately after surgery when they had completely recovered and regained consciousness from general anesthesia, and subsequently 4, 8, 12 and 24 hours thereafter. Pain was quantified using the visual analog scale (VAS) and the verbal rating scale (VRS). The time at which supplemental analgesic medication was first demanded in the postoperative period by the patient was also noted. RESULTS: The two groups were comparable for age, sex, body weight and the type of surgery they underwent. Because the data did not have a normal Gaussian distribution, the one-tailed Mann-Whitney test, being a nonparametric test, was adopted for statistical analysis. Accordingly, VAS and VRS values at all time intervals were significantly lower (p<.0001) in the study group as compared with the control group. This indicated significantly better pain relief in the study group. There was also a significant delay (p=.0041) in the first demand for supplemental analgesic medication in the postoperative period in the study group. No complication specific to the procedure was noted except for the development of postoperative urinary retention, which was transient and appropriately managed with urinary catheterization. CONCLUSIONS: Preemptive analgesia with a single caudal epidural injection of bupivacaine and tramadol is a safe, simple and effective method for postoperative pain relief. 相似文献
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Sue Jordan MB BCh PGCE Lecturer in Biological Sciences to pre- post-registration nurses 《Nurse education today》1994,14(6)
The growth of bioscience knowledge over the last two decades has increased the potential benefits of scientifically based patient care by contributing to the theory of clinical care. However, there is little evidence that knowledge, derived from the human biosciences is being fully incorporated into nursing theory and practice.Nursing has developed its own unique professional body of knowledge, heavily influenced by behavioural science. If nursing theory leans towards behavioural science, but practice is devoted to problems of biological disturbance, nursing may be facing a widening theory-practice gap, greater than other professions. The theory-practice gap in nursing may be widened by the exclusion of bioscience from nursing theory. Nurses' relative disinterest in the natural sciences can be attributed both to sociological reasons and to problems stemming from the symbol-object dichotomy that recur in the teaching of natural sciences. Reflection on practice and examination of education method are suggested as strategies for re-introducing bioscience into nursing theory and practice. A challenge facing nurse educators is the integration of biological science into the nurses' conceptual ecologies. For, if nursing fails to make bioscience its own, much of the clinical welfare of patients will become a medical monopoly. 相似文献
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A retrospective study was carried out to determine the relationship between parity and bone mineral density (BMD) in middle-aged women. Eight hundred and twenty-five woman aged 41–76 years were recruited from four general practice registers in Cambridge. Subjects were unselected as to their health status. Each subject completed a detailed health questionnaire. Participation rate was 50%. The main outcome measure was BMD measured at the spine (L2–4,n=825) and hip (neck, intertrochanter and Ward's triangle;n=817) by dual-energy X-ray absorptiometry (DXA) using the Hologic QDR-1000 densitometer. It was found that the unadjusted mean BMD was significantly higher at all sites among the parous women (p=0.031 to <0.00001), and remained significantly higher at the femoral neck (p=0.025), intertrochanter (p=0.001) and Ward's triangle (p=0.045) after adjusting for age and body mass index (BMI). Similar findings were seen after stratifying for potential confounding variables. There was a consistent upward trend of BMD with increasing parity at all sites. Parity remained a significant independent predictor of BMD at all sites after controlling for age, BMI, menopausal status, oral contraceptive and hormone replacement therapy use, smoking status and breast-feeding status in multiple linear regression analyses. There was, on average, a 1.0% increase in BMD per live birth. Our findings therefore suggest a positive relationship between parity and bone mass. 相似文献
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Ambakumar Nandakumar Narayanappa Anantha Thalagavadi Venugopal Sreerama Reddy Bapsy Padmanabhan Kumara Swamy Dinesh Doval Clementina Ramarao 《International journal of cancer. Journal international du cancer》1995,63(1):37-42
Lymphoid and haemopoietic malignancies as a group constitute one of the important cancers in India, as elsewhere in the world. While information on incidence and mortality of these cancers, and that on survival, are available from most developed countries, there are very few reports describing this experience in developing ones. Population-based cancer registration commenced in Bangalore, India, in January 1982, under the auspices of the Indian Council of Medical Research. This source provides fairly complete and reliable incidence data, but, in order to obtain mortality and survival information, active follow-up involving visits of homes of patients was undertaken. Between 1982 and 1989, 1397 cases of lymphoid and haemopoietic malignancies were registered in the Bangalore cancer registry, giving an age-adjusted incidence rate of 7.7 and 4.8 per 100,000 in males and females respectively. Active follow-up provided mortality/survival information in 1267 or 90.7% of these cases. The overall observed 5-year survival for these cancers combined (both sexes) was 26%, and relative survival 28.4%. The 5-year survival rate was lower in all the individual lymphomas and leukaemias as compared with similar reports from the developed countries. Survival in Hodgkin's disease was influenced by clinical stage and age at presentation. 相似文献