Implications for anaesthesia in a patient established on clozapine treatment.

Clozapine is an atypical antipsychotic agent with a novel pharmacological profile and multiple clinical properties. Because of its side effects, it is recommended in treatment of severe resistant schizophrenia for which purpose it is remarkably effective. Little is known about the safety profile of clozapine during pregnancy and labour and because it is now used more commonly to manage schizophrenia, it is important that we as anaesthetists are aware of its many interactions and potential side effects. We present a case of a successful emergency caesarean section in a schizophrenic patient on clozapine treatment.

A study of the educational and research priorities of registered nurses in rural Australia.

This study set out to identify the educational and research priorities of registered nurses practising in rural and remote areas of Australia. It included two groups of participants, one which identified as rural and another which identified as remote. The findings for the rural cohort in the study are presented in this article. Research participants represented a national sample. The Delphi method was used to obtain the most reliable consensus of the nurse participants. In the final phase of the study, 13 high priorities were identified. Study findings highlight perceived needs for clinical nursing research and continuing education for nurses practising in rural Australia.

Clinical nursing research priorities in Australian critical care: a pilot study.

The aims of this research project were to identify areas for research in Australian critical care nursing with potential for improvement in patient care, and to advise nursing research policy and priorities with relevance to areas of patients' needs. Research participants represented a national sample of clinical nurse specialists (CNSs) and clinical nurse consultants (CNCs). The Delphi method was used to obtain the most reliable consensus of the specialist nurses, and over 238 research priorities were identified initially. In the final phase of the research nine high priorities were identified. The findings of this study suggest directions for clinical nursing research in critical care.

Nurses and smoking: a comparative study of students of nursing and teaching.

This exploratory study compared three student groups (n = 221)--college student nurses, hospital student nurses and student teachers--in terms of their smoking behaviour, factors influencing smoking and their beliefs and values. More student nurses, both hospital and college students, smoked than student teachers while more hospital student nurses were smoking than college student nurses. The majority of students who smoked started smoking before they started their nursing and teaching courses. The influence of friends was the most important factor in starting smoking while enjoyment was the main reason for continuing to smoke. The risks in smoking were acknowledged by all groups. Student nurses were more likely to believe that smoking reduces stress levels. Hospital student nurses and student teachers were unconvinced about the health promotion role of nurses.

HIV/AIDS: knowledge and attitudes of accident and emergency healthcare professionals.

The knowledge and attitudes of healthcare professionals in accident and emergency departments in Australia are poorly understood. The authors assessed knowledge of and attitudes toward HIV/AIDS and homophobia were assessed in a convenience sample of 111 healthcare professionals in three New South Wales teaching hospitals. Results indicated that respondents with low knowledge of HIV/AIDS used the media as their major source of education and had higher levels of fear of infection than their colleagues with higher knowledge. The study findings imply that quality health care for people with HIV/AIDS requires programs that provide correct information and address the fear of infection.

A reevaluation of the Fe(II), Ca(II), Zn(II), and proton formation constants of 4,7-diphenyl-1,10-phenanthrolinedisulfonate.

The compound 4,7-diphenyl-1,10-phenanthrolinedisulfonic acid (BPDS) has been found to be very useful in studying Fe uptake by plants, because it forms a large charged complex that is not absorbed. The quantity of BPDS bound to metals in hydroponic solutions can be estimated from calculations using formation constants of BPDS complexes. These formation constants were used in an earlier experiment to predict the availability of Cu to corn plants. In the experiment, bioassays indicated that Cu was not as phytoavailable in the BPDS-added solutions as predicted by chemical equilibrium calculations. To determine sources of error in this prediction, metal and proton BPDS formation constants were reevaluated at 25 degrees C and 0.10M ionic strength. The CaBPDS formation constant was determined by direct measurement of CaBPDS3 formation and was shown to be approximately 1.0; a value much less than that reported before. Formation constants for the HBPDS, H(BPDS)2, and H(BPDS)3 beta 1, beta 2, and beta 3 complexes were, respectively, 5.05 +/- 0.044, 7.44 +/- 0.019, and 9.33 +/- 0.28. The BPDS sulfonic acid group pKs were less than 1.0, not 2.8 as has been reported. The FeBPDS3 complex determined by ligand competition with EDTA (ethylenediaminetetraacetate) was 20.24 +/- 0.08. Copper and Zn constants were determined using the method of corresponding solutions. The CuBPDS, CuBPDS2, and CuBPDS3 beta 1, beta 2, and beta 3 constants were, respectively, 9.76 +/- 0.08, 15.9, and 20.9. The ZnBPDS, ZnBPDS2, and ZnBPDS3 beta 1, beta 2, and beta 3 constants were, respectively, 6.43 +/- 0.07, 10.7 +/- 5.4, and 17.3 +/- 0.8. Results indicated that BPDS affinity to metals was similar to that of its parent compound, phenanthroline, and that errors in published formation constants caused erroneous predictions of Cu phytoavailability used in an earlier experiment.

Neuromuscular effects of pipecuronium bromide.

The neuromuscular effects of pipecuronium bromide have been evaluated in 90 adult patients anaesthetized with thiopentone, nitrous oxide in oxygen and intravenous fentanyl with or without halothane. Eighty patients received pipecuronium 45 micrograms kg-1 and the remaining ten 70 micrograms kg-1. A separate group of 10 patients received pancuronium in a dose of 60 micrograms kg-1 (equipotent to pipecuronium 45 micrograms kg-1). Neuromuscular block was measured using a single-twitch or train-of-four mode of stimulation. The time to onset of maximum block with pipecuronium 45 micrograms kg-1 varied between 3.5 and 5.7 min depending on the mode of stimulation and the anaesthetic technique used. The time to 25% recovery of this dose varied between 41 and 54 min. The recovery index (time from 25 to 75% recovery) averaged 29 min. These values were generally similar in the group receiving pancuronium 60 micrograms kg-1. The time to onset of complete block with 70 micrograms kg-1 of pipecuronium averaged 2.5 min and the duration to 25% recovery 95 min. There were no significant changes in heart rate and arterial pressure with the use of pipecuronium. The results show pipecuronium to be a drug resembling pancuronium in its neuromuscular effects when used in equipotent doses.

Dose-response studies of atracurium, vecuronium and pancuronium in the elderly.

Dose-response curves were constructed for atracurium, vecuronium and pancuronium in elderly subjects in order to assess potency of these relaxants. The results were compared to data previously obtained for adult subjects using the same method. A single-dose method of potency determination was used in both studies. The results indicate no significant difference in the potency of these relaxants between elderly and adult subjects; the ED95S were 249 and 226 micrograms/kg for atracurium, 43.1 and 39.6 micrograms/kg for vecuronium and 65.9 and 60 micrograms/kg for pancuronium respectively in the elderly and the adults.

Onset and duration of clinical relaxation of atracurium and vecuronium in patients on chronic nifedipine therapy.

The onset and duration of clinical relaxation of atracurium and vecuronium were studied in patients on chronic nifedipine therapy and compared to similar groups of patients not on such a therapy. Neuromuscular block was monitored by recording the integrated electromyogram of the hypothenar muscles (using a 'Datex Relaxograph') following stimulation of the ulnar nerve with a train-of-four stimulation. Neither the time to onset of maximum block (3.0-3.4 min) nor the duration of clinical relaxation (36-40 min) differed significantly between the groups indicating no significant interaction in humans between atracurium and vecuronium and chronic nifedipine therapy.

Iron-Stress Induced Redox Activity in Tomato (Lycopersicum esculentum Mill.) Is Localized on the Plasma Membrane.

Tomato plants (Lycopersicum esculentum Mill.) were grown for 21-days in a complete hydroponic nutrient solution including Fe(3+)-ethylenediamine-di(o-hydroxyphenylacetate) and subsequently switched to nutrient solution withholding Fe for 8 days to induce Fe stress. The roots of Fe-stressed plants reduced chelated Fe at rates sevenfold higher than roots of plants grown under Fe-sufficient conditions. The response in intact Fe-deficient roots was localized to root hairs, which developed on secondary roots during the period of Fe stress. Plasma membranes (PM) isolated by aqueous two-phase partitioning from tomato roots grown under Fe stress exhibited a 94% increase in rates of NADH-dependent Fe(3+)-citrate reduction compared to PM isolated from roots of Fe-sufficient plants. Optimal detection of the reductase activity required the presence of detergent indicating structural latency. In contrast, NADPH-dependent Fe(3+)-citrate reduction was not significantly different in root PM isolated from Fe-deficient versus Fe-sufficient plants and proceeded at substantially lower rates than NADH-dependent reduction. Mg(2+)-ATPase activity was increased 22% in PM from roots of Fe-deficient plants compared to PM isolated from roots of Fe-sufficient plants. The results localized the increase in Fe reductase activity in roots grown under Fe stress to the PM.

Residual metal concentrations in soils and leaf accumulations in tobacco a decade following farmland application of municipal sludge.

The objectives of this investigation were to examine the long-term residual effects of metal loading through sewage sludge applications on the total vs. diethylene triamine pentacetic acid (DTPA) extractable metal concentrations in soil and leaf accumulations in tobacco. Maryland tobacco (Nicotiana tabacum L.), cv. 'MD 609', was grown in 1983 and 1984 at two sites in Maryland that had been amended in 1972 with dewatered, digested sewage sludge from washington, DC, at rates equal to 0, 56, 112 and 224 mg ha(-1). The metal concentrations in the sludge, in mg kg(-1) dry weight, were: 1300 Zn, 570 Cu, 280 Pb, 45 Ni and 13 Cd. Soil samples collected from the surface horizon and composite leaf samples of cured tobacco were analyzed for total Zn, Cu, Mn, Fe, Pb, Ni and Cd concentrations. The soil samples were also examined for soil pH and DTPA extractable metals. Equations were generated using polynomic and stepwise regression analyses which described the relationships between total vs. DTPA extractable soil metals, and between DTPA soil and soil pH vs. plant metal concentrations, respectively. Significant increases were observed for both total and DTPA extractable metal concentrations for all metals, with all but total Mn and Ni being significant for linear and quadratic effects regarding sludge rates. However, linear relationships were found between DTPA extractable vs. total soil concentrations for all elements except Pb and Ni which were quadratic. Significant increases in plant Zn, Cu, Mn, Ni and Cd and decreases in Fe were observed with increased sludge rates. Plant Pb levels were unaffected by sludge applied Pb. Linear relationships were observed between plant Zn and Cd and DTPA soil metal levels: however, Mn and Cu levels were described by quadratic and cubic relationship, respectively. Relationships between plant Fe and Pb and DTPA extractable concentrations were nonsignificant. Additional safeguards to protect crop contamination from heavy metals such as Cd were discussed.

P6 acupressure reduces morning sickness.

A prospective study was designed to test the efficacy of pressure at the P6 (Neiguan) acupuncture point, in preventing morning sickness. Three groups of patients in early pregnancy recorded the severity and frequency of sickness over a period of 4 consecutive days following daily pressure at P6 point, pressure at a point near the right elbow and with no treatment. Troublesome sickness was significantly less in both the genuine (23/119) and dummy (41/112) pressure groups as compared with the control series (67/119). When the data are adversely 'weighted' to compensate for the lower incidence of fully completed returns in the active treatment groups, only the P6 group show a significant reduction in sickness. No side effects occurred in either group and while anticipation of benefit may offer a partial explanation for the findings, pressure at the Neiguan point appears to have a specific therapeutic effect.

Nalbuphine and pentazocine in an opioid-benzodiazepine sedative technique: a double-blind comparison.

Sedation by a combination of an opioid drug such as pentazocine with a benzodiazepine is commonly used for minor surgical and investigative procedures. Nalbuphine is a newer drug which, like pentazocine, is an opioid agonist-antagonist. Its actions are similar, but it has theoretical advantages in its profile of cardiovascular side effects. Nalbuphine or pentazocine in combination with diazepam were compared as components of a sedative technique for invasive radiology. The doses used were in the ratio of 2.5:1--ie nalbuphine 0.2 mg kg-1 and pentazocine 0.5 mg kg-1. Both regimens gave satisfactory results, and no difference could be detected between them in terms of sedation, analgesic efficacy, cardiovascular or respiratory changes, or recovery. Nalbuphine provides a safe and effective alternative to pentazocine in this situation. The study confirmed the need for caution because of the respiratory depressant effects of both drugs.