Tracheostomy tube occlusion during emergency tracheostomy in a pigmy goat

CorrespondenceLuiz C Santos, Robin D Gleed, Luis Campoy, Manuel Martin-Flores and John W Ludder

Effect of food withdrawal on arterial blood glucose and plasma 13, 14-dihydro-15-keto-prostaglandin F2 alpha concentrations and nocturnal myometrial electromyographic activity in the pregnant rhesus monkey in the last third of gestation: A model for prete

Pregnant rhesus monkeys were studied between 109 and 149 days of gestation. Food withdrawal for 48 hours (with free access to water) was accompanied by a decrease in maternal whole blood glucose concentration and an increased maternal arterial plasma 13,14-dihydro-15-keto-prostaglandin F(2α) concentration. On successive nights of the 48-hour period of food withdrawal, there was an increase in the frequency of myometrial contractions as recorded by uterine electromyogram. In the period after food was returned, blood glucose, arterial 13,14-dihydro-15-keto-prostaglanding F(2α) concentration, and contraction frequency returned to baseline. Because of food withdrawal results in the appearance of the nocturnal contraction pattern seen at term, we suggest that this experimental paradigm may be used as a model for preterm labor

What hinders pulmonary gas exchange and changes distribution of ventilation in immobilized white rhinoceroses (Ceratotherium simum) in lateral recumbency?

This study used electrical impedance tomography (EIT) measurements of regional ventilation and perfusion to elucidate the reasons for severe gas exchange impairment reported in rhinoceroses during opioid-induced immobilization. EIT values were compared with standard monitoring parameters to establish a new monitoring tool for conservational immobilization and future treatment options. Six male white rhinoceroses were immobilized using etorphine, and EIT ventilation variables, venous admixture, and dead space were measured 30, 40, and 50 min after becoming recumbent in lateral position. Pulmonary perfusion mapping using impedance-enhanced EIT was performed at the end of the study period. The measured impedance (∆Z) by EIT was compared between pulmonary regions using mixed linear models. Measurements of regional ventilation and perfusion revealed a pronounced disproportional shift of ventilation and perfusion toward the nondependent lung. Overall, the dependent lung was minimally ventilated and perfused, but remained aerated with minimal detectable lung collapse. Perfusion was found primarily around the hilum of the nondependent lung and was minimal in the periphery of the nondependent and the entire dependent lung. These shifts can explain the high amount of venous admixture and physiological dead space found in this study. Breath holding redistributed ventilation toward dependent and ventral lung areas. The findings of this study reveal important pathophysiological insights into the changes in lung ventilation and perfusion during immobilization of white rhinoceroses. These novel insights might induce a search for better therapeutic options and is establishing EIT as a promising monitoring tool for large animals in the field

Estudo comparativo entre pancurônio e vecurônio em cães submetidos à facectomia extracapsular Comparative study between pancuronium and vecuronium in dogs submitted to lens extraction

Neste estudo foram comparados os efeitos do pancurônio e do vecurônio em cães submetidos a facectomia extracapsular. Foram utilizados 24 cães hígidos, de diferentes sexos e raças, com idade média de 6,8 &plusmn; 2,0 anos e peso médio de 10,0 &plusmn; 6,4 quilos. Os animais receberan como medicação pré-anestésica acepromazina. A anestesia foi induzida através do uso de midazolam e tiopental, sendo a manutenção da anestesia realizada com halotano em oxigênio a 100% com auxílio de aprelho com sistema circular. Posteriormente a este protocolo, os animais foram distribuídos em dois grupos: grupo I onde imediatamente antes do início da cirurgia, receberam pancurônio e o grupo II onde no mesmo momento receberam vecurônio, sendo observados os períodos de latência através da paralisação respiratória e o hábil através da recuperação da respiração espontânea, assim como o período de centralização do globo ocular. Previamente a administração do bloqueador neuromuscular e aos 1, 5, 10, 15 e 20 minutos da sua aplicação foram avaliadas a freqüência e ritmo cardíaco, a pressão arterial sistólica, média e diastólica e a saturação periférica da hemoglobina, sendo os valores obtidos submetidos a análise estatística, não tendo sido observadas diferenças estatisticamente signifcativas entre os valores obtidos. Os valores médios e desvios-padrões dos períodos de latência do pancurônio e do vecurônio foram respectivamente 93,5 &plusmn; 38,9 e 80,8 &plusmn; 25,5 segundos, considerados adequados, uma vez que possibilitam a rápida instituição da ventilação controlada sem que ocorresse hipoxemia. A centralização do globo ocular foi obtida em 31,4 &plusmn; 18,2 segundos com pancurônio e 39,8 &plusmn; 19,7 segundos com vecurônio, apresentando estes resultados difirença estatisticamente significativa. O período hábil do pancurônio foi significativamente maior que o do vecurônio (respectivamente 33,6 &plusmn; 7.1 e 23,9 &plusmn; 6,3 minutos), porém os dois agentes possuem duração suficiente para a realização do procedimento cirúrgico em questão.<br>In this study the effects of pancuronium and vecuronium were compared in dogs submitted to lens extraction. Twenty four healthy male and female dogs, of different breeds, with 6.8 &plusmn; 2.0 years and mean weight of 10.0 &plusmn; 6.4 kilograms were used. All animals received acepromazine as the pre-anesthetic medication. Anesthesia was induced with midazolam and thiopentone and halothane was used as the maintenance agent in 100% oxygen with a circular system. After this animals were randomized in two groups: animals of group I received pancuronium and those from group II received vecuronium. Onset time evaluated by means of respiratory arrest as well as duration of action were verified by the moment spontaneous respiration reassumed and time to eye centralisation. Heart rate and rhythm, systolic, meand and diastolic blood pressure as well as hemoglobin saturation were measured before neuromuscular block administration and 1, 5, 10, 15 and 20 minutes after its administration. Data were submitted to statistical analyzes that consisted of analyzes of variance (ANOVA) for repeated measures fallowed by Tukey post test for the evaluation of the different moments in the same group and Student T test for the differences between the groups. The statistical analyses did not show any difference between treatments or between different moments in the group. Mean values and standard deviation of onset time for pancuronium and vecuroniun were 93.5 &plusmn; 38.9 and 80.8 &plusmn; 25.5 seconds respectively, that were considered adequate once hypoxemia did not occurr when controlled ventilation were instituted. Eye centralization occurred 31.4 &plusmn; 18.2 seconds after pancuronium and 39.8 &plusmn; 19.7 seconds after vecuronium and these values were statistically different. Duration of action of pancuratium was significantly longer than that werified for vecuroniun and this values were 33.6 &plusmn; 7.1 and 23.9 &plusmn; 6.3 minutes. Nevertheless both agents showed a reasonable duration of action and the surgical procedure could be performed unevetfully