Thesis (M.A.)--University of Delaware, 2006. / Principal faculty advisor: Cynthia Robbins, Dept. of Sociology. Includes bibliographical references.

Thesis (D. Psych.)--Victoria University (Melbourne, Vic.), 2008. / Includes bibliographical references.

Orientador: Valéria Nobre Leal de Souza Oliva / Banca: Paulo Sérgio Patto dos Santos / Banca: Renata Navarro Cassu / Banca: Stélo Pacca Loureiro Luna / Banca: Juliana Noda Bechara Belo / Resumo: Há controvérsia na literatura sobre a determinação do período exato que corresponde à classificação dos pacientes caninos em neonatos ou pediátricos. Contudo, sabe-se que até 6 semanas de idade estes animais apresentam imaturidade do sistema respiratório, cardiovascular, sistema nervoso central, hepático e renal. Tal imaturidade dos sistemas pode interferir na disponibilidade dos fármacos e na resposta destes à anestesia. Alguns fatores influenciam diretamente a concentração alveolar mínima (CAM) dos anestésicos inalatórios sendo a idade um destes. Há escassa literatura a respeito da influencia da idade na CAM dos anestésicos inalatórios. Desta maneira, este trabalho tem o objetivo de determinar a concentração alveolar mínima (CAM) do sevofluorano em cães jovens nas diferentes faixas etárias pré-determinadas pelos pesquisadores. Foram utilizados oito filhotes de cães, da raça Retriever do Labrador, submetidos à anestesia inalatória com sevofluorano aos 30, 45, 60 e 90 (± 2) dias de idade. A monitoração foi composta de freqüência cardíaca, freqüência respiratória, pressão arterial sistólica não-invasiva, oximetria de pulso, hemogasometria arterial e temperatura retal, concentração de sevofluorano (ETsev) e dióxido de carbono (ETco2) no final da expiração. A ETsev ao final da expiração foi mantida em 3% por no mínimo 15 minutos para a realização do estímulo supramáximo doloroso e determinação da CAM que constitiu-se em pinçamento de cauda durante 60 segundos ou menos, caso a resposta fosse positiva. Quando a resposta ao primeiro estímulo fosse negativa, a concentração de sevofluorano foi diminuída em 0,2% em relação a concentração inicial (3%) e o estímulo foi repetido após 15 minutos, para possibilitar a estabilização do circuito. Se, inicialmente... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: In the literature we researched certain difficulty could be noted in the determination of the exact period for the classification of canine patients in neonates and pediatrics. However, it is anyway known that until 6 weeks of age these animals have very immature respiratory, cardiovascular, central nervous system, hepatic, and renal systems. Such immaturity of their organic systems may interfere in the drug disponibility and reaction, as well as in their reaction to the anaesthesic agent. Some factors interfere directly in the minimum alveolar concentration (MAC) of inhalant anaesthesics, and age is certainly one of them. There is a shortage of studies about age influence over MAC of inhalant anaesthesical agents. So, this work is aimed to determine the minimum alveolar concentration (MAC) of sevoflurane in young dogs, divided in different age groups by researchers. Eight Labrador Retriever baby dogs underwent inhalant anaesthesia with sevoflurane in the ages of 30, 45, 60 and 90 (+/-2) days. The checkup included heart and breath frequencies, non-invasive systolical blood pressure pulse oximetry, arterial blood gas and rectal temperature, sevoflurane (ETsev) and carbon dioxide (ETCO2) concentrations in the end of the expiration. ETsev in the end of expiration was kept at 3% for at least 15 minutes for the accomplishment of the pain stimulus and MAC determination. For that, dogs were stimulated with tail clamping during 60 seconds or less, whether reaction were positive. When the reaction to the first stimulation were negative, sevoflurane concentration was decreased in 80% of its initial concentration (1.5 MAC), as well as the stimulus was repeated after 15 minutes, in order to stabilise the circuit. Whether in the beginning the answer were positive, the anaesthesic concentration was then increased in 20% and after 15 minutes a new stimulation was tried. This scheming was repeated as many times as it was necessary to achieve the negative. / Doutor

Made available in DSpace on 2014-06-11T19:35:05Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-02-21Bitstream added on 2014-06-13T20:25:56Z : No. of bitstreams: 1 gabas_dt_dr_botfm.pdf: 757225 bytes, checksum: 677a131f18a6dc5bb3200cf95bed51ce (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Há controvérsia na literatura sobre a determinação do período exato que corresponde à classificação dos pacientes caninos em neonatos ou pediátricos. Contudo, sabe-se que até 6 semanas de idade estes animais apresentam imaturidade do sistema respiratório, cardiovascular, sistema nervoso central, hepático e renal. Tal imaturidade dos sistemas pode interferir na disponibilidade dos fármacos e na resposta destes à anestesia. Alguns fatores influenciam diretamente a concentração alveolar mínima (CAM) dos anestésicos inalatórios sendo a idade um destes. Há escassa literatura a respeito da influencia da idade na CAM dos anestésicos inalatórios. Desta maneira, este trabalho tem o objetivo de determinar a concentração alveolar mínima (CAM) do sevofluorano em cães jovens nas diferentes faixas etárias pré-determinadas pelos pesquisadores. Foram utilizados oito filhotes de cães, da raça Retriever do Labrador, submetidos à anestesia inalatória com sevofluorano aos 30, 45, 60 e 90 (± 2) dias de idade. A monitoração foi composta de freqüência cardíaca, freqüência respiratória, pressão arterial sistólica não-invasiva, oximetria de pulso, hemogasometria arterial e temperatura retal, concentração de sevofluorano (ETsev) e dióxido de carbono (ETco2) no final da expiração. A ETsev ao final da expiração foi mantida em 3% por no mínimo 15 minutos para a realização do estímulo supramáximo doloroso e determinação da CAM que constitiu-se em pinçamento de cauda durante 60 segundos ou menos, caso a resposta fosse positiva. Quando a resposta ao primeiro estímulo fosse negativa, a concentração de sevofluorano foi diminuída em 0,2% em relação a concentração inicial (3%) e o estímulo foi repetido após 15 minutos, para possibilitar a estabilização do circuito. Se, inicialmente... / In the literature we researched certain difficulty could be noted in the determination of the exact period for the classification of canine patients in neonates and pediatrics. However, it is anyway known that until 6 weeks of age these animals have very immature respiratory, cardiovascular, central nervous system, hepatic, and renal systems. Such immaturity of their organic systems may interfere in the drug disponibility and reaction, as well as in their reaction to the anaesthesic agent. Some factors interfere directly in the minimum alveolar concentration (MAC) of inhalant anaesthesics, and age is certainly one of them. There is a shortage of studies about age influence over MAC of inhalant anaesthesical agents. So, this work is aimed to determine the minimum alveolar concentration (MAC) of sevoflurane in young dogs, divided in different age groups by researchers. Eight Labrador Retriever baby dogs underwent inhalant anaesthesia with sevoflurane in the ages of 30, 45, 60 and 90 (+/-2) days. The checkup included heart and breath frequencies, non-invasive systolical blood pressure pulse oximetry, arterial blood gas and rectal temperature, sevoflurane (ETsev) and carbon dioxide (ETCO2) concentrations in the end of the expiration. ETsev in the end of expiration was kept at 3% for at least 15 minutes for the accomplishment of the pain stimulus and MAC determination. For that, dogs were stimulated with tail clamping during 60 seconds or less, whether reaction were positive. When the reaction to the first stimulation were negative, sevoflurane concentration was decreased in 80% of its initial concentration (1.5 MAC), as well as the stimulus was repeated after 15 minutes, in order to stabilise the circuit. Whether in the beginning the answer were positive, the anaesthesic concentration was then increased in 20% and after 15 minutes a new stimulation was tried. This scheming was repeated as many times as it was necessary to achieve the negative.

Thesis (M.A.) - Carleton University, 2007. / Includes bibliographical references (p. 128-138). Also available in electronic format on the Internet.

The most commonly used method of euthanasia of laboratory rodents is exposure to carbon dioxide (CO₂), but recent studies have shown that rodents find this gas aversive. The aim of my thesis was to evaluate rat aversion to inhalant agents that could be used as humane alternatives to CO₂. The first study used approach-avoidance testing to examine rat responses to argon-induced hypoxia when argon was introduced at flow rates of 40-239% of the test cage volume per min. Rats never remained in the test cage long enough to lose consciousness when tested with argon. They consumed fewer reward items, stopped eating sooner, and left the test cage more quickly than when tested with air. Rats stopped eating and left the test cage when the oxygen (O₂) concentration had dropped to about 7.7 and 6.8%, respectively, but these O₂ concentrations are too high to cause unconsciousness. Although humans exposed to hypoxia report only subtle symptoms that include cognitive impairments and light headedness, rats are burrowing rodents and could therefore be more sensitive to these effects. I conclude that argon is not a humane alternative to CO₂. The second study used approach-avoidance testing to evaluate rat responses to different concentrations of the inhalant anaesthetics halothane and isoflurane introduced with vaporizers or from soaked cotton balls. On the first day of exposure to anaesthetics, most rats remained in the test cage until they were ataxic and showing difficulty returning to the home cage. On subsequent days of testing most rats left the test cage within seconds, but if given the option, all promptly returned and stayed until they were ataxic, indicating that the learned aversion is transient. Rats were likely sedated by the time they chose to leave, suggesting that forced exposure from the onset of aversion until loss of consciousness is less of a welfare concern than forced exposure to non-sedating agents. I suggest that the use of inhalant anaesthetics for inducing unconsciousness prior to euthanasia is a more humane method than the commonly used CO₂.

The most commonly used method of euthanasia of laboratory rodents is exposure to carbon dioxide (CO₂), but recent studies have shown that rodents find this gas aversive. The aim of my thesis was to evaluate rat aversion to inhalant agents that could be used as humane alternatives to CO₂. The first study used approach-avoidance testing to examine rat responses to argon-induced hypoxia when argon was introduced at flow rates of 40-239% of the test cage volume per min. Rats never remained in the test cage long enough to lose consciousness when tested with argon. They consumed fewer reward items, stopped eating sooner, and left the test cage more quickly than when tested with air. Rats stopped eating and left the test cage when the oxygen (O₂) concentration had dropped to about 7.7 and 6.8%, respectively, but these O₂ concentrations are too high to cause unconsciousness. Although humans exposed to hypoxia report only subtle symptoms that include cognitive impairments and light headedness, rats are burrowing rodents and could therefore be more sensitive to these effects. I conclude that argon is not a humane alternative to CO₂. The second study used approach-avoidance testing to evaluate rat responses to different concentrations of the inhalant anaesthetics halothane and isoflurane introduced with vaporizers or from soaked cotton balls. On the first day of exposure to anaesthetics, most rats remained in the test cage until they were ataxic and showing difficulty returning to the home cage. On subsequent days of testing most rats left the test cage within seconds, but if given the option, all promptly returned and stayed until they were ataxic, indicating that the learned aversion is transient. Rats were likely sedated by the time they chose to leave, suggesting that forced exposure from the onset of aversion until loss of consciousness is less of a welfare concern than forced exposure to non-sedating agents. I suggest that the use of inhalant anaesthetics for inducing unconsciousness prior to euthanasia is a more humane method than the commonly used CO₂.

The most commonly used method of euthanasia of laboratory rodents is exposure to carbon dioxide (CO₂), but recent studies have shown that rodents find this gas aversive. The aim of my thesis was to evaluate rat aversion to inhalant agents that could be used as humane alternatives to CO₂. The first study used approach-avoidance testing to examine rat responses to argon-induced hypoxia when argon was introduced at flow rates of 40-239% of the test cage volume per min. Rats never remained in the test cage long enough to lose consciousness when tested with argon. They consumed fewer reward items, stopped eating sooner, and left the test cage more quickly than when tested with air. Rats stopped eating and left the test cage when the oxygen (O₂) concentration had dropped to about 7.7 and 6.8%, respectively, but these O₂ concentrations are too high to cause unconsciousness. Although humans exposed to hypoxia report only subtle symptoms that include cognitive impairments and light headedness, rats are burrowing rodents and could therefore be more sensitive to these effects. I conclude that argon is not a humane alternative to CO₂. The second study used approach-avoidance testing to evaluate rat responses to different concentrations of the inhalant anaesthetics halothane and isoflurane introduced with vaporizers or from soaked cotton balls. On the first day of exposure to anaesthetics, most rats remained in the test cage until they were ataxic and showing difficulty returning to the home cage. On subsequent days of testing most rats left the test cage within seconds, but if given the option, all promptly returned and stayed until they were ataxic, indicating that the learned aversion is transient. Rats were likely sedated by the time they chose to leave, suggesting that forced exposure from the onset of aversion until loss of consciousness is less of a welfare concern than forced exposure to non-sedating agents. I suggest that the use of inhalant anaesthetics for inducing unconsciousness prior to euthanasia is a more humane method than the commonly used CO₂. / Land and Food Systems, Faculty of / Graduate

This study analyzed the effects of acculturation, locus of control, and incidence of inhalant use on Mexican Americans. Information was collected from 275 subjects at three middle schools and one treatment center. The instrument consisted of Levenson's Locus of Control Scale, the Acculturation Rating Scale for Mexican Americans, and an incidence of use and family relationship questionnaire developed for this study. Statistical analysis indicated a relationship between acculturation and inhalant use. Further examination revealed relationships between a family members' use and subjects' inhalant use; subjects' alcohol use and inhalant use; and subjects' marijuana use and inhalant use. Information implied that prevention and intervention programs should focus on children of substance users and further research is needed surrounding the role of acculturation.

Nitrous oxide (N2O) is a widely used anesthetic adjunct in dentistry and medicine that is also commonly abused. N2O alters the function of several receptors in vitro and ex vivo, however, the receptors systems underlying its abuse-related intoxicating effects are poorly understood. The goals of this dissertation were to (1) establish N2O as a discriminative stimulus, (2) characterize the temporal properties of the discriminative stimulus, (3) determine the degree of similarity between N2O and other inhalants and (4) explore the neurochemical effects responsible for the stimulus properties of N2O. Twenty-four mice were trained to discriminate 10 minutes exposure to 60% N2O+40% O2 from 100% O2 in daily 5 minute food-reinforced operant sessions. Mice acquired the discrimination in a mean of 38 sessions. N2O produced concentration-dependent full substitution for itself. Full substitution required 7 minutes of N2O exposure but the offset of stimulus effects following cessation of N2O exposure were more rapid. Varying degrees of partial substitution for N2O were engendered by abused vapors and vapor anesthetics. The aromatic hydrocarbon toluene produced the most robust substitution for N2O. One or more toluene concentrations produced full substitution for N2O in 7 of 8 subjects, suggesting that these two abused inhalants share common neurochemical mechanisms. The NMDA receptor open channel blockers (+)-MK-801, ketamine and memantine produced dose-dependent partial substitution for N2O. A competitive NMDA antagonist and NMDA glycine site antagonist did not substitute for N2O. Pretreatment with (+)-MK-801 as well as ethanol produced dose-dependent leftward shifts in the N2O concentration effect curve further suggesting some overlap in their mechanisms of action. GABAA agonists and positive allosteric modulators, opioid agonists, serotonergic agonists, nicotine, a nNOS inhibitor and the psychomotor stimulant amphetamine all failed to appreciably substitute for N2O and/or failed to alter the N2O concentration effect curve when administered prior to N2O exposure. No drug tested produced greater than 80% mean N2O-lever selection leaving open the possibility of other neurochemical contributors to the stimulus effects of N2O.