PubMed · 6869731
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M R Nott, J Norman. 1983. The Lack system.. https://doi.org/10.1111/j.1365-2044.1983.tb12137.x
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UNLABELLED: BACKGROUND AND STUDY GOALS: Strabismus surgery in children is frequently associated with a very high incidence of postoperative nausea and vomiting (PONV). In this study we investigated, whether TIVA is superior to inhalation anaesthesia concerning PONV when a prophylaxis using dimenhydrinate (diphenhydramine chlorotheophyllate) is administered in both groups. METHODS: 110 patients (3-10 years) were prospectively and randomly allocated to one of the following groups: Group TD (TIVA/dimenhydrinate; n= 55): anaesthesia was induced and maintained using remifentanil and propofol in common clinical dosages. Patients were ventilated with 30% O(2) in air. Group VD (Volatile/ dimenhydrinate; n= 55): anaesthesia was induced and maintained with sevoflurane in common clinical concentrations together with N(2)O in 30% O(2). All patients received dimenhydrinate 1 mg.kg(-1) i.v. after induction. PONV was recorded within the first 24 h postoperatively. The chi-square test and a multivariate analysis were used for statistical analysis. RESULTS: 52 patients of group TD and 54 of group VD were analysed. There was a trend in the incidence of postoperative nausea (PN): group TD 17%, 95% CI: 8-30%) compared to group VD 31%, 95% CI: 20-46%), p = 0.09. No difference was seen for PV and PONV: 21% (95% CI: 11-35%) in group TD vs. 35% (95% CI: 23-49%) in group VD, p = 0.109. These non-significant results can be easily attributed to the lack of power about 30%) of this study. According to the results of the multivariate analysis volatile anaesthesia was identified as an independent risk factor for PONV (OR: 2.92, 95% CI: 1.02-8.36). Other variables that were found to be an independent risk factor included history of PONV (OR: 8.19, 95% CI: 1.84-36.43), surgery lasting longer than 30 min (OR: 5.89, 95% CI: 1.82-19.82) and "Faden-operations" (retroequatorial myopexy) (OR: 5.48, 95% CI: 1.74-17.21). CONCLUSIONS: TD only showed a trend to lower PN incidences and no differences as for PV and PONV incidences, most likely due to a lack of power of this study. However, according to the results of the multivariate analysis, inhalation anaesthesia was shown to be an independent risk factor for PONV, as were history of PONV, surgery >30 min and "Faden-operations".
Studies on tumor angiogenesis and antiangiogenic therapies are commonly performed with tumor heterotransplants in nude mice. To monitor therapeutic effects, improved noninvasive analyses of functional data are required, in addition to the assessment of tumor volume and histology. Here, we report on sequential monitoring of vascularization of human squamous cell carcinomas growing as heterotransplants in nude mice using MRI. Using a custom-developed animal coil in a conventional whole-body 1.5 T MRI scanner, dynamic T1w sequences were recorded after i.v. injection of Gd-DTPA in tumors grown for 17, 21, 25, 29 and 33 days. Amplitude and the exchange rate constant (k(ep)) were calculated according to a 2-compartment model, discriminating intravascular and interstitial spaces, and correlated with tumor size and histology. High-resolution imaging of small heterotransplants from 100 to 1,000 mm(3) was achieved, clearly discriminating vital and necrotic areas. Preceding the development of necroses, which were hyperintense in T2w images and confirmed with histology, a local decrease of amplitude and k(ep) values was observed. Significantly higher amplitudes were found in tumor periphery than in central parts, correlating well with the vascular pattern obtained by immunocytochemistry. Tumor size correlated negatively with amplitude, probably as a result of increasing necrotic areas, whereas the reason for the observed increase of k(ep) value with tumor size remains unclear. These data demonstrate that dynamic MRI is an excellent method for noninvasive assessment of tumor vascularization in small animals using a clinical whole-body scanner with little technical modifications. This technique provides functional data characterizing essential features of tumor biology and is thus appropriate for monitoring antiangiogenic therapies.
OBJECTIVE: Purpose of this study was to find out the effect of positional change and inhalant anesthesia on acoustic reflectometry (AR) parameters (reflectivity and curve angle). METHOD: AR parameters were measured on 58 ears with otitis media in sitting position before anesthesia and in supine position under inhalant anesthesia, subsequently. RESULTS: Under anesthesia, ears with effusion disclosed more changes in reflectivity (Chi-squared analysis, chi2-test; P<0.05) and curve angle (P>0.1) than those without effusion. Further, inhalant anesthesia caused more changes in the false negative ears (63.63%) than in those with effusion having positive test before anesthesia (12.90%) (P<0.001). CONCLUSIONS: From the data of this study, it could be said that reflectivity shows changes according to the amount of effusion which is in contact with the tympanic membrane under anesthesia, and that curve angle becomes more sensitive to detect effusion when anesthetic gas diffuses into the middle ear with effusion, probably due to the pushing of effusion towards the tympanic membrane.