A randomized trial comparing sevoflurane and propofol in children undergoing MRI scans

Objectives:  We compared three primary outcomes of pausing the magnetic resonance imaging (MRI) scan, emergence quality and respiratory complications.
Aim:  To measure and compare the quality between sevoflurane and propofol in children undergoing MRI scans.
Background:  No randomized controlled trial exists comparing the quality between sevoflurane and propofol for MRI.
Methods/Materials:  Two hundred unpremedicated children (18 months to 7 years) scheduled for brain MRI scans were recruited. After induction with sevoflurane, children were randomized to receive sevoflurane [general anesthesia with sevoflurane (GAS)] via laryngeal mask airway (LMA) or propofol [general anesthesia with propofol (GAP)] bolus and infusion for their scan. The three primary outcomes of pausing the MRI scan (P), agitation (A), and respiratory complications (R) were compared. Timeliness of care was also measured.
Results:  No MRI scan pauses were found in 92% and 80% in the GAS and GAP groups. The median and interquartile A scores were 3 (0, 7) in GAS and 0 (0, 4) in GAP groups respectively. There was no difference in respiratory complications between GAS and GAP ( P  = 0.62). The median and interquartile postanesthesia care unit (PACU) times were 25 (18, 34) for GAS and 31 (25, 44) for GAP ( P  = 0.0001). The median and interquartile total times were 78 (69, 90) for GAS and 88 (78, 100) for GAP ( P  = 0.0002).
Conclusion:  Our study compared the three primary outcomes of pausing, agitation, and respiratory complications between the two groups, and we found no difference in respiratory complications. However, the GAP group had more pausing and less agitation than the GAS group.     

Very high doses of valsartan provide renoprotection independently of blood pressure in a type 2 diabetic nephropathy rat model

Aim:   Angiotensin II type 1 receptor blockers (ARB) retard the progression of hypertensive diabetic kidney disease. Clinical evidence suggests that the dose of ARB required to correct hypertension is suboptimal for renoprotection evaluated by proteinuria. No systematic, prospective study has yet evaluated separately the effect of increasing doses of ARB on blood pressure and proteinuria.
Methods:   Over a period of 8 weeks, the effect of seven constant doses of an ARB, valsartan (4–160 mg/kg per day), on blood pressure and proteinuria taken as a surrogate marker of nephropathy in a hypertensive, type 2 diabetic rat model, the spontaneously hypertensive/NIH-corpulent rat (SHR/NDmcr-cp), was assessed. In this spontaneously hypertensive rat strain, a genetic mutation in the leptin receptor gene is associated with hyperphagia leading to obesity with metabolic syndrome and eventually to nephropathy.
Results:   No additional blood pressure lowering was observed above 120 mg/kg per day of valsartan, suggesting that a dose of 80–120 mg/kg per day had a maximal effect. Nevertheless, higher doses of valsartan further reduced proteinuria in a dose-dependent fashion suggesting the absence of a maximal dose. Obesity, hyperglycaemia and hypercholesterolaemia were unaffected but hypertriglyceridaemia was partially corrected at various ARB doses.
Conclusion:   ARB improve renoprotection at doses above those required for a maximal effect on blood pressure. The mechanism of the renoprotection obtained at high doses of ARB is yet to be elucidated.     

Inbred mice infected with Plasmodium yoelii differ in their antimalarial immunoglobulin isotype response

Antibodies are known to be important in mediating malarial immunity, but the influence of the various immunoglobulin isotypes on parasite elimination is unclear. The purpose of this study was to provide basic information on the induction of isotype expression in genetically different mice during primary malaria. Parasitaemias and the serum antimalarial IgM, IgG1, IgG2, IgG3 and IgA antibody titres measured in a radioimmunoassay were followed in outbred and 11 inbred strains of mice infected with 17XNL Plasmodium yoelii. Severity of infection, as judged by length of infection, peak parasitaemias and death, was found to differ between the strains. All strains developed rapid IgM responses, but only 3/11 inbred strains produced significant antimalarial IgG1 levels during primary infection. All strains produced an IgG2 response, which developed slightly more quickly in strains with the least severe courses of malaria. A large variation in the IgG3 response was noted between strains. In general, IgG3 antibodies were the first IgG-isotype to appear in serum. They were detected as early as day 8 in strains that developed mild infections but were not present until around day 20 in strains with the most severe cases of malaria. Only one strain produced detectable antimalarial IgA antibodies. These results show that different patterns of isotype expression are induced in inbred strains of mice during primary P. yoelii infection.     

The Haematological and Biochemical Changes in Severe Pulmonary Tuberculosis

This study surveys the extent and severity of haematologicaland biochemical abnormalities which occurred in 265 patientswith pulmonary tuberculosis, and records the haematologicalchanges that occur with treatment. Anaemia was present in 60 per cent of patients, more frequentlyin males than in females. Leucocytosis with neutrophilia occurredin 40 per cent, lymphopenia in 17 per cent and monocytopeniain 50 per cent. Platelet count and erythrocyte sedimentationrate were elevated in 52 and 80 per cent respectively. Bonemarrow aspiration and trephine biopsy were of limited diagnosticvalue. Ferritin and vitamin B₁₂ levels were increased in 94and 57 per cent of subjects respectively whilst serum and redcell folic acid were within normal limits in 83 per cent. Thefrequency of the important biochemical changes were hyponatraemia(43 per cent) and hypoalbuminaemia (72 per cent); alkaline phosphatase,aspartic transaminase and lactic dehydrogenase levels were elevatedin approximately a third of patients possibly due to unsuspecteddissemination. There was a close correlation between the acid-fast bacilliin sputum and abnormal values, particularly those of body weight,haemoglobin, platelet count, whlte cell count and erythrocytesedimentation rate. Failure of these indices to return to normalwas invariably associatd with persistent excretion of acid-fastbacilli. We have shown that haematological and biochemical abnormalitiesin pulmonary tuberculosis are common and may be valuable aidsto diagnosis. Some haematological markers also reflect resporrseto treatment.     

Preliminary Toxicity Profile of Arotinoids SMR-2 and SMR-6 in Male B6D2F1 Mice

Preliminary Toxicity Profile of Arotinoids SMR-2 and SMR-6 inMale B6D2F1 Mice. LINDA-MOOD, C, III, GILES, H. D., AND HILL,D. L. (1987). Fundam. Appl. Toxicol. 8, 517–530. Arotinoids,which are analogs of retinoic acid (RA) and retinol (RO) withthe carbon skeleton in a rigid conformation, have more favorabletherapeutic indices relative to all-transRA and al-trans-RO.The purpose of this investigation was to obtain preliminaryin vivo toxicity data on SMR-2 (analog of RO) and SMR-6 (analogof RA), arotinoids with promising activity (ED50's of 20 x 10^–11and 5 x 10^–11 m, respectively; ED50 of RA = 1 x 10^–11m) for reversal of keratinization in tracheal organ culture.A preliminary toxicity study was conducted in male B6D2F1 micewith gavage of retinoids in corn oil (0.01, 0.05, and 0.1 mg/kg/dayof SMR-2 or SMR-6; 1, 5, and 10 mg/kg/day of RA as referencecontrol). Due to lack of toxicity, each dose level for SMR-2and SMR-6 was increased by 4-fold on Day 29 of dosing. The studywas terminated on Day 57. Hypervitaminosis A (weight loss, alopecia,skin scaling, and bone thinning) was induced in the mid- andhigh-dose SMR groups; weight-gain depression was predominantin the high-dose RA group. The SMR compounds were approximately100-fold more toxic, based on weight loss, than RA. In the SMRdose groups with hypervitaminosis A, white blood cell countswere elevated 2- to 4-fold; and there were microscopic lesionsin skin, testes, epididymis, bone, thymus, bone marrow, peripherallymph nodes, spleen, stomach, adrenal, and pituitary. The leuko-cytosiswas attributed to leukopoiesis in spleen and bone marrow, whichmay be due to either a direct effect and/or a secondary responseto a subacute inflammatory reaction in skin. Only peripherallymph node hyperplasia was observed in SMR-2 and RA low-dosegroups. Enlarged thymus, lymph node hyperplasia, leukopoiesisin spleen and bone marrow, elevated alkaline phosphatase withbone hypertrophy, and testicular degeneration were observedin the mid-dose RA group. The results indicate that immune stimulationmay be a primary early response to retinoids and that skin,leukopoietic tissues, reproductive organs, stomach, and boneare primary targets for retinoid toxicity.     

The impact of 1992 on food law

The essential purpose of food law is consumer protection while quality judgement is a matter for the individual, based on informative labelling. Although the Council has agreed major frameworks directives, much detailed work is still required including; an agreed common list of food additives; the problems of the constituents of packaging materials and their possible migration into food; the assessment of quality of dietary products for their declared aims; limits for environmental contaminants; the approach to be adopted for biotechnology products and the labelling of foods containing ingredients which have been irradiated.     

Computerized Pacemaker Patient Analysis

BYRD, C.B., ET AL.: Computerized Pacemaker Patient Analysis. We have developed computer hardware and software that imports analog waveforms and other measured data from a patient into the PaceBase database system supported by any IBM PC/AT compatible. The programmable AID converter has the capacity to acquire the pacemaker artifact from the surface ECG leads. Analysis of the pacemaker artifact permits confirmation of pulse width as well as programmability and facilitates discovery of pacemaker hardware failures otherwise undetectable. Continuous recording of real-time surface ECG can be made as other measurements or storing functions are being performed. In this way, sporadic or infrequent intrinsic events are automatically recorded and can be selected to be played back and reviewed or stored on the permanent record. Pacemaker spike detection enhances identification of paced and intrinsic complexes by emphasizing the paced artifact. Even bipolar atrial spikes with pulse widths as short as 0.05 ms are easily identified; myopotential muscle noise is rejected. Enhancement of pacemaker spikes takes the guesswork out of interpretation of ECGs, especially for bipolar systems and when testing or troubleshooting for myopotential tracking or inhibition.     

Overview: The treatment of drug dependence

Addictive disorders resemble other chronic medical disorders in that they are characterized by relapses and remissions. This central feature of the addictions is addressed by many of the contributors in their individual chapters. There are also several specific points raised in the chapters which merit further discussion. For instance, any assumption that long–term anti–anxiety treatment with benzodiazepines implies a form of dependence that requires treatment could be set against an alternative view that there may be appropriate medical/psychiatric indications for such prolonged treatment. There are also interesting questions which deserve discussion surrounding the debate over treatment setting for opiate dependence treatments. The paper by Johns presents a case for inpatient treatment whereas in the United States long–term methadone maintenance is seen as one of the most effective treatments. Given the complexity of the bio–psycho–social mechanisms involved in Addiction a combination of therapeutic approaches tailored to individual needs should probably continue to be the guiding principle.