Remifentanil-ketamine vs. propofol-ketamine for sedation in pediatric patients undergoing colonoscopy: A randomized clinical trial / Remifentanil-cetamina vs. propofol-cetamina para sedação em pacientes pediátricos submetidos à colonoscopia: ensaio clínico randômico

Abstract Background and objectives: Pediatric patients frequently require deep sedation or general anesthesia for colonoscopy. This study was designed to compare the sedative efficacy of remifentanil-ketamine combination with propofol-ketamine combination in children undergoing colonoscopy. Methods: Seventy patients, between 2 and 16 years of age, scheduled for diagnostic colonoscopy were randomly allocated into two groups. Remifentanil-ketamine group received intravenous ketamine 2 mg.kg−1 and remifentanil 0.25 µg.kg−1 combination, followed by 0.1 µg.kg−1.min−1 remifentanil infusion. Propofol-ketamine group received intravenous propofol 1 and 2 mg.kg−1 ketamine combination, followed by 1 mg.kg−1.h−1 propofol infusion. In the case of children discomfort (cry, movement, and cough), remifentanil 0.1 µg.kg−1 in the remifentanil-ketamine group or propofol 0.5 mg.kg−1 in the propofol-ketamine group were administered to improve children discomfort. Despite the therapy given above, if children still experience discomfort, 1 mg.kg−1 of ketamine was administered as a rescue drug, regardless of the group. Ramsay sedation score, hemodynamic variables, drug requirements, gastroenterologists' satisfaction, colonoscopy duration, recovery time, and side effects were recorded throughout the procedure and the recovery period. Results: The percentage of patients with a Ramsay sedation score of 4 or higher during the procedure was 73.5 and 37.1% in remifentanil-ketamine and propofol-ketamine groups, respectively (p = 0.02). Systolic and diastolic blood pressure variables were significantly higher only after induction in the remifentanil-ketamine group than in the propofol-ketamine group (p = 0.015). Conclusion: Coadministration of ketamine with either remifentanil or propofol effectively and safely provides sedation and analgesia in children undergoing colonoscopy. Sedation scores were significantly better in remifentanil-ketamine group than in propofol-ketamine group.

Resumo Justificativa e objetivos: Os pacientes pediátricos com frequência precisam de sedação profunda ou anestesia geral para colonoscopia. Este estudo foi desenhado para comparar a eficácia sedativa da combinação de remifentanil-cetamina e de propofol-cetamina em crianças submetidas à colonoscopia. Métodos: Setenta pacientes, entre 2-16 anos, programados para colonoscopia diagnóstica foram alocados randomicamente em dois grupos. O grupo remifentanil-cetamina recebeu a combinação de 2 mg.kg−1 de cetamina por via intravenosa e 0,25 µg.kg−1 de remifentanil; seguido de infusão de remifentanil (0,1 µg.kg−1.min−1). O grupo propofol-cetamina recebeu a combinação de 1 mg.kg−1 de propofol e 2 mg.kg−1 de cetamina; seguido de infusão de propofol (1 mg.kg−1.h−1). Em caso de desconforto das crianças (choro, movimento e tosse), remifentanil (0,1 µg.kg−1) seria administrado ao grupo remifentanil-cetamina ou propofol (0,5 mg.kg−1) ao grupo propofol-cetamina. A despeito da terapia acima citada, caso as crianças ainda sentissem desconforto, cetamina (1 mg.kg−1) seria administrada como fármaco de resgate, independentemente do grupo. Escore de sedação de Ramsay, variáveis hemodinâmicas, necessidade de medicamentos, satisfação dos gastroenterologistas, duração da colonoscopia, tempo de recuperação e efeitos colaterais foram registrados durante o procedimento e o período de recuperação. Resultados: O percentual de pacientes com escore 4 ou mais na escala de sedação de Ramsay durante o procedimento foi de 73,5% e 37,1% nos grupos remifentanil-cetamina e propofol-cetamina, respectivamente, (p = 0,02). As variáveis, pressão arterial sistólica e diastólica, foram significativamente maiores no grupo remifentanil-cetamina do que no grupo propofol-cetamina, mas somente após a indução (p = 0,015). Conclusão: A coadministração de cetamina com remifentanil ou propofol fornece sedação e analgesia de forma eficaz e segura em crianças submetidas à colonoscopia. Os escores de sedação foram significativamente melhores no grupo remifentanil-cetamina do que no grupo propofol-cetamina.

Tourniquet-induced ischaemia-reperfusion injury: the comparison of antioxidative effects of small-dose propofol and ketamine / Lesão de isquemia-reperfusão induzida por torniquete: comparação dos efeitos antioxidantes de propofol e cetamina em doses baixas

Abstract Objectives: The aim of the present study was to investigate the preventive effects of propofol and ketamine as small dose sedation during spinal anaesthesia on tourniquet-induced ischaemia-reperfusion injury. Methods: 30 patients were randomly assigned into two groups of 15 patients. In the propofol group, sedation was performed with propofol 0.2 mg·kg-1 followed by infusion at a rate of 2 mg·kg-1·h-1. In the ketamine group, a continuous infusion of ketamine 0.5 mg·kg-1·h-1 was used until the end of surgery. Intravenous administration of midazolam was not used in any patients. Ramsay sedation scale was used for assessing the sedation level. Venous blood samples were obtained before propofol and ketamine infusion (T1), at 30 minutes (min) of tourniquet ischaemia (T2), and 5 min after tourniquet deflation (T3) for malondialdehyde (MDA) measurements. Results: No differences were noted between the groups in haemodynamic (p > 0.05) and demographic data (p > 0.05). There was no statistically significant difference between the two groups in terms of T1, T2 and T3 periods (p > 0.05). There was a statistically increase observed in MDA values respectively both in Group P and Group K between the reperfusion period (1.95 ± 0.59, 2.31 ± 0.48) and pre-ischaemia (1.41 ± 0.38, 1.54 ± 0.45), and ischaemia (1.76 ± 0.70, 1.71 ± 0.38) (µmoL-1) periods (p < 0.05). Conclusions: Small-dose propofol and ketamine has similar potential to reduce the oxidative stress caused by tourniquet-induced ischaemia-reperfusion injury in patients undergoing arthroscopic knee surgery under spinal anaesthesia.

Resumo Objetivos: O objetivo do presente estudo foi investigar os efeitos preventivos de propofol e cetamina em sedação com doses baixas durante a raquianestesia sobre lesão de isquemia-reperfusão induzida por torniquete. Métodos: 30 pacientes foram randomicamente alocados em dois grupos de 15 pacientes cada. No grupo propofol, a sedação foi feita com 0,2 mg.kg-1 de propofol seguida por infusão a uma taxa de 2 mg.kg-1.h-1. No grupo cetamina, uma infusão contínua de 0,5 mg.kg-1.h-1 de cetamina foi usada até o final da cirurgia. Midazolam intravenoso não foi administrado em nenhum dos pacientes. A Escala de Sedação de Ramsay (ESR) foi usada para avaliar o nível de sedação. Amostras de sangue venoso foram colhidas antes da administração de propofol e infusão de cetamina (T1), aos 30 minutos (min) de isquemia do torniquete (T2) e 5 min após a desinsuflação do torniquete (T3), para medir os valores de malondialdeído (MDA). Resultados: Não observamos diferenças entre os grupos em relação à hemodinâmica (p > 0,05) e dados demográficos (p > 0,05). Não houve diferença estatisticamente significativa entre os dois grupos nos períodos T1, T2 e T3 (p > 0,05). Um aumento estatisticamente significativo foi observado nos valores de MDA, respectivamente, no Grupo P e Grupo C entre os períodos de reperfusão (1,95 ± 0,59, 2,31 ± 0,48) e pré-isquemia (1,41 ± 0,38, 1,54 ± 0,45) e isquemia (1,76 ± 0,70, 1,71 ± 0,38) (µmoL-1) (p < 0,05). Conclusões: Propofol e cetamina em doses baixas apresentam potencial semelhante para reduzir o estresse oxidativo causado pela lesão de isquemia-reperfusão induzida por torniquete em pacientes submetidos à artroscopia de joelho sob raquianestesia.

Sympathetic activity of S-(+)-ketamine low doses in the epidural space / Atividade simpática de cetamina S-(+) em doses baixas no espaço epidural / Actividad simpática de la ketamina S(+)-en dosis bajas en el espacio epidural

BACKGROUND AND OBJECTIVES: S-(+)-ketamine is an intravenous anaesthetic and sympathomimetic with properties of local anaesthetic. It has an effect of an analgetic and local anaesthetic when administered epidurally, but there are no data whether low doses of S-(+)-ketamine have sympathomimetic effects. The aim of this study was to determine whether low doses of S-(+)-ketamine, given epidurally together with local anaesthetic, have any effect on sympathetic nervous system, both systemic and below the level of anaesthetic block. METHODS: The study was conducted on two groups of patients to whom epidural anaesthesia was administered to. Local anaesthesia (0.5% bupivacaine) was given to one group (control group) while local anaesthesia and S-(+)-ketamine were given to other group. Age, height, weight, systolic, diastolic and mean arterial blood pressure were measured. Non-competitive enzyme immunochemistry method (Cat Combi ELISA) was used to determine the concentrations of catecholamines (adrenaline and noradrenaline). Immunoenzymometric determination with luminescent substrate on a machine called Vitros Eci was used to determine the concentration of cortisol. Pulse transit time was measured using photoplethysmography. Mann-Whitney U-test, Wilcoxon test and Friedman ANOVA were the statistical tests. Blood pressure, pulse, adrenaline, noradrenaline and cortisol concentrations were measured in order to estimate systemic sympathetic effects. RESULTS: 40 patients in the control group were given 0.5% bupivacaine and 40 patients in the test group were given 0.5% bupivacaine with S-(+)-ketamine. Value p < 0.05 has been taken as a limit of statistical significance. CONCLUSIONS: Low dose of S-(+)-ketamine administered epidurally had no sympathomimetic effects; it did not change blood pressure, pulse, serum hormones or pulse transit time. Low dose of S-(+)-ketamine administered epidurally did not deepen sympathetic block. Adding 25 ...

JUSTIFICATIVA E OBJETIVOS: cetamina S-(+) é um anestésico intravenoso e simpaticomimético com propriedades de anestésico local. Tem efeito analgésico e de anestésico local quando administrada por via epidural, mas não há dados que relatem se cetamina S-(+) em doses baixas tem efeitos simpaticomiméticos. O objetivo deste estudo foi determinar se cetamina S-(+) em doses baixas, administrada por via epidural em combinação com anestésico local, tem algum efeito sobre o sistema nervoso simpático, tanto sistêmico quanto abaixo do nível do bloqueio anestésico. MÉTODOS: o estudo foi conduzido com dois grupos de pacientes submetidos à anestesia epidural. Anestesia local (bupivacaína a 0,5) foi administrada a um grupo (controle), enquanto anestesia local em combinação com cetamina S-(+) foi administrada ao outro grupo (teste). Idade, altura, peso, pressão arterial sistólica e diastólica e pressão arterial média foram medidos. O método imunoquímico de inibição enzimática não competitiva (Cat Combi Elisa) foi usado para determinar as concentrações de catecolaminas (adrenalina e noradrenalina). O ensaio imunoenzimométrico com substrato luminescente em uma máquina chamada Vitros Eci foi usado para determinar a concentração de cortisol. O tempo de transição do pulso foi medido com fotopletismografia. Para análise estatística, os testes de Wilcoxon, U de Mann-Whitney e Anova de Friedman foram usados. Pressão arterial, pulso e concentrações de adrenalina, noradrenalina e cortisol foram medidos para estimar os efeitos simpáticos sistêmicos. RESULTADOS: receberam bupivacaína a 5% 40 pacientes do grupo controle e 40 do grupo teste receberam bupivacaína a 0,5% com cetamina S-(+). Um valor de p < 0,05 foi ...

JUSTIFICACIÓN Y OBJETIVOS: la ketamina S(+) es un anestésico intravenoso y simpaticomimético con propiedades de anestésico local. Posee un efecto analgésico y de anestésico local cuando se administra por vía epidural, pero no existen datos que informen si la ketamina S(+) en bajas dosis tiene efectos simpaticomiméticos. El objetivo de este estudio fue determinar si la ketamina S(+) en bajas dosis y administrada por vía epidural en combinación con el anestésico local tiene algún efecto sobre el sistema nervioso simpático, tanto sistémico como por debajo del nivel del bloqueo anestésico. MÉTODOS: el estudio fue realizado con 2 grupos de pacientes sometidos a anestesia epidural. A un grupo (grupo control) se le administró la anestesia local (bupivacaína al 0,5), mientras que a otro se le administró la anestesia local en combinación con la ketamina S(+). La edad, altura, peso, presión arterial sistólica y diastólica y la presión arterial media se midieron. El método inmunoquímico de inhibición enzimática no competitiva (Cat Combi ELISA) se usó para determinar las concentraciones de catecolaminas (adrenalina y noradrenalina). El ensayo inmunoenzimométrico con sustrato lumínico en una máquina llamada Vitros Eci fue usado para determinar la concentración de cortisol. El tiempo de transición del pulso fue medido usando la fotopletismografía. Para el análisis estadístico se usaron los test de Wilcoxon, U de Mann-Whitney y ANOVA de Friedman. La presión arterial, pulso y concentraciones de adrenalina, noradrenalina y cortisol fueron medidos para estimar los efectos simpáticos sistémicos. RESULTADOS: cuarenta pacientes del grupo control recibieron bupivacaína al 5% y 40 pacientes del grupo test recibieron bupivacaína al 0,5% con ketamina ...

Effects caused by the spinal administration of ketamine S (+) 5% with no preservatives, using a single puncture, and located on the spinal cord and meninges in rabbits

PURPOSE: To evaluate the effect of ketamine S (+) 5% with no preservatives and administered as a subarachnoid single puncture on the spinal cord and meninges of rabbits. METHODS: Twenty young adult female rabbits, each weighing 3500-5000 g and having a spine length between 34 and 38 cm, were divided by lot into two groups (G): 0.9% saline in G1 and ketamine S (+) 5% in G2, by volume of 5 μg per cm column (0.18 mL). After intravenous anaesthesia with ketamine and xylazine, the subarachnoid space was punctured at S1-S2 under ultrasound guidance, and a random solution was injected. The animals remained in captivity for 21 days under medical observation and were sacrificed by decapitation. The lumbosacral spinal cord portion was removed for immunohistochemistry to assess the glial fibrillary acidic protein (GFAP), and histology was assessed using hematoxylin and eosin (HE) stain. RESULTS: No histological lesions were found in the nervous tissue (roots and cord) or meninges in either group. CONCLUSION: The ketamine S (+) 5% unpreserved triggered no neurological or histological lesions in the spinal cord or meninges of rabbits. .

Ketamine alters behavior and decreases BDNF levels in the rat brain as a function of time after drug administration

Objective: To evaluate behavioral changes and brain-derived neurotrophic factor (BDNF) levels in rats subjected to ketamine administration (25 mg/kg) for 7 days. Method: Behavioral evaluation was undertaken at 1 and 6 hours after the last injection. Results: We observed hyperlocomotion 1 hour after the last injection and a decrease in locomotion after 6 hours. Immobility time was decreased and climbing time was increased 6 hours after the last injection. BDNF levels were decreased in the prefrontal cortex and amygdala when rats were killed 6 hours after the last injection, compared to the saline group and to rats killed 1 hour after the last injection. BDNF levels in the striatum were decreased in rats killed 6 hours after the last ketamine injection, and BDNF levels in the hippocampus were decreased in the groups that were killed 1 and 6 hours after the last injection. Conclusion: These results suggest that the effects of ketamine on behavior and BDNF levels are related to the time at which they were evaluated after administration of the drug. .

Electro-acupuncture reduces the need for additional anesthetics in experimental studies / Eletroacupuntura reduz a necessidade de doses adicionais de anestésicos em estudos experimentais

PURPOSE: To evaluate the possible beneficial effects of electro-acupuncture in rats subjected to ketamine/xylazine (KX) intra-peritoneal (i.p.) anesthesia. METHODS: Forty-eight male Wistar rats were distributed in four equal groups. All rats received i.p. injections of ketamine (90 mg/kg) +xylazine (10 mg/kg) anesthesia. Basal values group (control) rats (BV) received no additional treatment. The equivalent of the human right ST36 (Zusanli) and CV-12(Zhongwan) acupoints were chosen for needling and electrical stimulation. AC rats were needled with sterilized disposable stainless steel needles at right ST36 and CV12 acupoints; needles were retained for 30 minutes. EAC10 rats, after needle insertion as described, had electrodes connected to both needles and to an electro stimulator model NKL EL-608; pulsed square waves, 10 Hz, 10 mA, was applied for 30 minutes. EAC100 rats were submitted to EA as described. However, a greater frequency (100 Hz) was used. RESULTS: Thirty-seven rats remained under adequate anesthetic level during the experiment. However, maintenance anesthesia was required by 11 rats. Need for additional anesthesia decreased to 9.1 percent in EAC100 rats compared to BV (36.3 percent). CONCLUSION: Both the AC and the EAC10/100 prolong the anesthetic effect of the combination Ketamine-xylazine in rats, allowing longer duration of anesthesia with a lower dose of anesthetic, thereby reducing the occurrence of complications.

OBJETIVO: Avaliar os possíveis efeitos benéficos da eletroacupuntura em ratos submetidos à anestesia intraperitoneal (i.p.) com ketamina / xilazina. MÉTODOS: Quarenta e oito ratos Wistar foram randomizados em quatro grupos iguais. Todos os ratos receberam injeções i.p. de ketamina (90 mg / kg) + xilazina (10 mg / kg). Os ratos do grupo Valores Basais (controle - BV) não receberam nenhum tratamento adicional. Os acupontos equivalentes aos humanos E-36 (Zusanli) e VC-12 (Zhongwan) foram escolhidos para inserção de agulhas e estimulação elétrica. Os ratos do grupo AC foram estimulados com agulhas esterilizadas descartáveis, de aço inoxidável, nos acupontos E-36 direito e VC12. As agulhas foram mantidas por 30 minutos. Nos ratos do grupo EAC10, após agulhamento, como descrito, eletrodos foram conectados às agulhas e ao eletro-estimulador modelo NKL EL-608 e aplicadas ondas quadradas pulsantes, 10 Hz, 10 mA, por 30 minutos. Os ratos do grupo EAC100 foram submetidos à EA como descrito. No entanto, uma maior freqüência (100 Hz) foi utilizada. RESULTADOS: Trinta e sete ratos permaneceram no nível anestésico adequado durante o experimento. No entanto, a manutenção da anestesia foi se fez necessária em 11 animais. Nos ratos do grupo EAC100 a necessidade de anestesia complementar diminuiu para 9,1 por cento em comparação com ratos do grupo BV (36,3 por cento). CONCLUSÃO: Tanto a AC como a EAC10/100 prolongam o efeito anestésico da combinação ketamina-xilazina em ratos, permitindo maior duração da anestesia com menor dose de anestésico, reduzindo assim a ocorrência de complicações.

Avaliação dos níveis séricos de lactato em cães submetidos a anestesia dissociativa / Evaluación de los niveles séricos de lactato en perros sometidos a anestesia dissociativa / Seric level assessment of lactate in dogs submitted to dissociative anesthesia

A mensuração da lactatemia como indicador indireto da oxigenação dos tecidos e, por conseguinte, de estresse e acidemia, tem potencial para se tornar uma ferramenta muito útil em medicina veterinária. Neste estudo, 10 cães domésticos adultos clinicamente saudáveis foram anestesiados pela associação de tiletamina, zolazepam, xilazina e atropina, em doses calculadas por meio de extrapolação alométrica intraespecífica. A lactatemia foi mensurada por meio de reação enzimática, com leitura por fotometria de reflectância, 1.140 minutos e um minuto antes da administração da associação anestésica por via intramuscular, aos 10, 20, 40, 60, 80, 180, 360, 720, 1.140, 2.880 e 14.440 minutos após a injeção. O comportamento das concentrações de lactato frente aos eventos experimentais evidenciou normalidade antes e depois da anestesia, e queda significativa durante a mesma. Concluiu-se que a anestesia dissociativa pela associação de tiletamina, zolazepam, xilazina e atropina, em doses calculadas por meio de extrapolação alométrica intraespecífica, não eleva a lactatemia. De fato, durante a anestesia ocorreu queda significativa das concentrações de lactato em relação aos níveis considerados basais.

Lactate level measuring as an indirect indicator of tissue oxygenation, and consequently stress and acidemia, isa potentially useful tool for Veterinary Medicine. In this study 10 adult healthy dogs were anesthetized with the combination of tiletamine, zolazepam, xylazine and atropine, with dosages calculated by intraespecific allometric scaling. Blood lactate was measured by enzymatic reaction with reflectancy photometry 1.140 and one minute before intramuscular administration of the anesthetic combination, and at 10, 20, 40, 60, 80, 180, 360, 720, 1,140, 2.880 and 14.440 minutes after the injection. Serum lactate concentrations were normal prior and after anesthesia, and presented significant decrease throughout it. It was concluded that the combination of tiletamina, zolazepam, xylazine and atropine in allometrically scaled dosages do not increase lactatemia. In fact, significant decrease of lactate serum concentrations in comparison with basal levels was observed during anesthesia.

La mensuración de la lactatemia como indicador indirecto de la oxigenación de los tejidos, así como de estrés y acidemia, tiene potencial para tornarse una herramienta muy útil en medicina veterinaria. En este estudio fueron anestesiados 10 perros adultos saludables con la asociación de tiletamina, zolazepam, xilacina y atropina, en dosis calculadas por medio de extrapolación alométrica intraespecífica. La lactatemia fue mensurada por medio de reacción enzimática, con evaluación porfotometría de reflectancia, 1.140 minutos y un minuto antes de la suministración de la combinación anestésica por vía intramuscular,y a los 10, 20, 40, 60, 80, 180, 360, 720, 1.140, 2.880 y 14.440 minutos después de la inyección. El comportamiento de las concentraciones de lactato delante de los eventos experimentales evidenció normalidad antes y después de la anestesia, y caída significativa durante la misma. Se concluyó que la anestesia disociativa por la combinación de tiletamina, zolazepam, xilacina y atropina, en dosis calculadas por medio de extrapolación alométrica intraespecífica, no eleva la lactatemia. De facto, durante la anestesia ocurrió caída significativa de las concentraciones de lactato en relación a los niveles considerados basales.

Intravenous ketamine plus midazolam vs. intravenous ketamine for sedation in lumbar puncture: a randomized controlled trial.

OBJECTIVE: To compare a combined dose of ketamine and midazolam versus ketamine alone in the sedation of children requiring lumbar puncture. STUDY DESIGN: A randomized, controlled study, conducted between January 2004 and December 2006. SETTING: The Pediatric Emergency Department (PED) at Ankara Training and Research Hospital, Turkey. PARTICIPANTS: A random sample of 99 children (59 boys, 40 girls) aged 2-14 years (mean age 6.5+/-3.7) undergoing lumbar puncture. INTERVENTION: Participants were randomized to receive intravenous (IV) ketamine only (1 mg/kg; IVK) (n=51) or ketamine plus midazolam (1 mg/kg ketamine+0.1 mg/kg midazolam; IVKM) (n=48). MAIN OUTCOME MEASURES: The mean time to sedation and adverse events. RESULTS: The mean time to sedation was significantly shorter in the IVKM group than the IVK group (2.6+/-1.1 and 3.4+/-1.7 min, respectively; P=0.01). The parental satisfaction was significantly higher in the IVKM group (P=0.001). Also the fasting time and recovery time did not differ between groups, nor was there a significant difference in nausea/vomiting between groups. Nightmares or crying spells were more common in the IVK group than in the IVKM group (P=0.04). CONCLUSIONS: We conclude that adding midazolam to ketamine did not increase the frequency of adverse events and that the combined sedative was superior to ketamine alone in terms of speed of sedation and parental satisfaction.

Avaliação das associações anestésicas: atropina/cetamina-s/xilazina e acepromazina/cetamina-s/midazolam em felinos domésticos (Felis domestica) / The evaluation of the anesthetic associations: atropine/s-ketamine/xylazine and acepromazine/ketamine-s/midazolam in domestic felines (Felis domestica)

Com o objetivo de avaliar as associações anestésicas atropina/cetamina-s/xilazina e acepromazina/cetamina-s/midazolam em felinos domésticos (Felis catus), foram utilizados 16 felinos, machos, hígidos cedidos por proprietários atendidos no Hospital Veterinário da Escola Superior de Agricultura de Mossoró. Os animais foram distribuidos aleatoriamente em dois grupos de oito animais, onde foi utilizado um tratamento anestésico distinto para cada grupo. O grupo I, foi pré-tratado com sulfato de atropina (0,044mg/kg) por via subcutânea, e decorridos 15 minutos, recebeu xilazina (1,0 mg/ kg) associada a cetamina-s (10mg/kg) por via intramuscular. No grupo II, foi utilizada acepromazina (0,2 mg/kg) por via intramuscular e após 15 minutos, administrou-se a associação de midazolam (0,5mg/ kg) e cetamina-s (10 mg/kg) por via intramuscular. Foram avaliadas as variáveis fisiológicas: freqüência cardíaca, freqüência respiratória, saturação de oxigênio e tempo de preenchimento capilar. A aferição das variáveis foi realizada a cada 10 minutos, durante 90 minutos. Também foi avaliado o período de latência, período de analgesia e de recuperação. A média do período de latência após a administração de atropina/ cetamina-s/xilazina foi de 3,68min, enquanto na acepromazina/cetamina-s/midazolam foi de 3,95 min. No grupo I, a média do tempo de analgesia foi de 45,94min, e no grupo II foi obtida analgesia em apenas um animal. A média do tempo de recuperação no grupo I foi de 134, 08min e no grupo lI, 78,28min. Concluiu-se que a associação atropina/ cetamina-s/xilazina, produz uma anestesia de boa qualidade para pequenos procedimentos cirúrgicos, enquanto que a associação acepromazina/cetamina-s/midazolam deve ser utilizada para pequenos procedimentos ambulatoriais. Ambas associações apresentam propriedades farmacológicas comparáveis com as obtidas com a cetamina racêmica.

Propofol for pediatric radiotherapy.

OBJECTIVE: Pediatric radiotherapy is a day care procedure. In children, anaesthesia is necessary to prevent movement during the therapy. Traditionally intramuscular ketamine is used for these procedure because of its inherent safety in a child who used to be left alone in the cobalt room. METHODS: This study was designed to explore the efficacy of propofol and ketamine in pediatric radiotherapy in nineteen children. The inclusion criteria was a child fasting for six hours with no fever or URTI in the past week. A child coming to the radiotherapy (RT) unit without an intravenous cannula was given intramuscular ketamine 10 mg/kg and taken for the procedure. Before the child recovered from anaesthesia an intravenous cannula, 20-22G, Vasofix was inserted for subsequent sittings of RT. The child coming with an intravenous cannula was given propofol 2.5 mg/kg with xylocaine (0.1 mg/kg) without adrenaline. The parameters recorded were pulse rate, oxygen saturation and respiratory rate-baseline to every 30 seconds till five minutes. Onset time, recovery time, oral feeding time and any untoward effects like nausea, vomiting, nystagmus were also noted. RESULT: The drug was graded on a scale of 0-10 according to parental acceptability where 0 is the worst and 10 is the best acceptability. The mean (+/-SD) of all the measured parameters were calculated and compared between the two groups. CONCLUSION: Propofol was associated with faster onset, better recovery, early oral feeding time, no nausea and vomiting and better parental acceptability. There was no hypotension, bradycardia and oxygen saturation at 60 seconds, which was between 94-95%, was easily treatable with supplementation of oxygen by face mask.

Oral ketamine for radiotherapy in children with cancer.

Children coming for radiotherapy under sedation usually get repeated injections, which cause distress to both the child and the parents. A prospective study was conducted to evaluate the efficacy of oral ketamine for sedation for radiotherapy (RT) in children with cancer. Ten children who received 49 sittings of RT were given 8-15 mg/kg body weight of oral ketamine. The onset time, recovery time, efficacy of sedation and incidence of abnormal movements were compared with another group of 8 children, who received intramuscular ketamine in the dose of 6 mg/kg for a total of 28 sittings of RT. Onset time and recovery time were significantly longer in oral ketamine group as compared to the intramuscular group (p < 0.001). Limb movements in patients receiving oral ketamine necessitated further supplement of sedation and interruption of RT. These drawbacks discourage use of oral ketamine as a good sedative for radiotherapy treatment in paediatric oncology patients.

Ketamine as an anaesthetic agent for tubal sterilisation.

OBJECTIVE: In most developing countries there is a dearth of qualified anaesthesiologists to administer general anaesthesia for tubal sterilisation. This study was done to determine whether ketamine could be safely used by non-specialist doctors as an anaesthetic for open tubal ligation. METHOD: A retrospective observational study of 4851 tubal sterilisations done under ketamine anaesthesia. All patients were given diazepam 0.1 mg/kg body weight intravenously followed by intravenous ketamine 2 mg/kg body weight slowly over one minute. All sterilisations were performed by Pomeroys method by a specialist or a senior house officer with specialist supervision. RESULTS: There were no major adverse reactions such as cardio-respiratory arrest following administration of ketamine. Hallucinations and transient psychotic sequalae were a common occurrence during the postoperative period. In 96% of patients the procedure was pain free. CONCLUSION: Ketamine given by non-specialist doctors can be recommended in carefully selected patients when there is a dearth of qualified anaesthesiologists for tubal sterilisations.