Effect of passive pneumoperitoneum on oesophageal pressure, cardiovascular parameters and blood gas analysis in horses

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Evaluation of a portable clinical analyzer for the determination of blood gas partial pressures, electrolyte concentrations, and hematocrit in venous blood samples collected from cattle, horses, and sheep

Objective To compare results reported for blood gas partial pressures, electrolyte concentrations, and Hct in venous blood samples collected from cattle, horses, and sheep and analyzed by use of a portable clinical analyzer (PCA) and reference analyzer (RA).Animals-Clinically normal animals (24 cattle, 22 horses, and 22 sheep).Procedures-pH; Pco(2); Po(2); total carbon dioxide concentration; oxygen saturation; base excess; concentrations of HCO(3)(-), Na(+), K(+), and ionized calcium; Hct; and hemoglobin concentration were determined with a PCA. Results were compared with those obtained for the same blood sample with an RA. Bias (mean difference) and variability (95% confidence interval) were determined for all data reported. Data were also subjected to analyses by Deming regression and Pearson correlation.Results-Analysis of Bland-Altman plots revealed good agreement between results obtained with the PCA and those obtained with the RA for pH and total carbon dioxide concentration in cattle, K(+) concentration in horses and sheep, and base excess in horses. Except for Na(+) concentration and Hct in horses and sheep, correlation was good or excellent for most variables reported.Conclusions and Clinical Relevance-Data from blood gas and electrolyte analyses obtained by use of the PCA can be used to evaluate the health status of cattle, horses, and sheep. Furthermore, the handheld PCA device may have a great advantage over the RA device as a result of the ability to analyze blood samples on farms that may be located far from urban centers. (Am J Vet Res 2010;71:515-521)

The effects of 2 levels of the inspired oxygen fraction on blood gas variables in propofol-anesthetized dogs with high intracranial pressure

The influence of 2 different levels of the inspired oxygen fraction (FiO(2)) on blood gas variables was evaluated in dogs with high intracranial pressure (ICP) during propofol anesthesia (induction followed by a continuous rate infusion [CRI] of 0.6 mg/kg/min) and intermittent positive pressure ventilation (IPPV). Eight adult mongrel dogs were anesthetized on 2 occasions, 21 d apart, and received oxygen at an FiO(2) of 1.0 (G100) or 0.6 (G60) in a randomized crossover fashion. A fiberoptic catheter was implanted on the surface of the right cerebral cortex for assessment of the ICP. An increase in the ICP was induced by temporary ligation of the jugular vein 50 min after induction of anesthesia and immediately after baseline measurement of the ICP. Blood gas measurements were taken 20 min later and then at 15-min intervals for 1 h. Numerical data were submitted to Morrison's multivariate statistical methods. The ICP, the cerebral perfusion pressure and the mean arterial pressure did not differ significantly between FiO(2) levels or measurement times after jugular ligation. The only blood gas values that differed significantly (P < 0.05) were the arterial oxygen partial pressure, which was greater with G100 than with G60 throughout the procedure, and the venous haemoglobin saturation, that was greater with G100 than with G60 at M0. There were no significant differences between FiO(2) levels or measurement times in the following blood gas variables: arterial carbon dioxide partial pressure, arterial hemoglobin saturation, base deficit, bicarbonate concentration, pH, venous oxygen partial pressure, venous carbon dioxide partial pressure and the arterial-to-end-tidal carbon dioxide difference.

Intraocular pressure and its correlation with blood gas parameters in crested caracaras (Caracara plancus) anesthetized with isoflurane and sevoflurane

Avaliou-se a pressão intra-ocular (PIO) e estimaram-se as correlações entre PIO e pressão de dióxido de carbono (PaCO2) e pH arterial de cinco caracarás (Caracara plancus), anestesiados com isofluorano (ISO) ou sevofluorano (SEV). Valores basais da PIO foram aferidos em ambos os olhos (M0). Cateterizou-se previamente a artéria braquial para obtenção de parâmetros hemogasométricos e cardiorrespiratórios. Anestesia foi induzida com ISO a 5V% e mantida por 40 minutos com 2,5V%. PIO e amostras de sangue foram avaliadas em diferentes momentos até o final do procedimento. Após recuperação, uma segunda anestesia foi realizada com SEV a 6% e mantida com 3,5%. Os parâmetros foram aferidos nos mesmos momentos estabelecidos previamente. A PIO decresceu significativamente (P=0,012) de M0 em todos os momentos e não houve diferença estatística entre ISO e SEV. Correlações significativas entre PIO e PaCO2 e entre PIO e pH sangüíneo foram observadas apenas para a anestesia com SEV. O pH sangüíneo decresceu paralelamente a PIO, enquanto a PaCO2 aumentou, em carcarás anestesiados com isofluorano e sevofluorano.

Effects of feeding a multivalent polyclonal antibody preparation on feedlot performance, carcass characteristics, rumenitis, and blood gas profile in Bos indicus biotype yearling bulls

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

The effects of ice-water storage on blood gas and acid-base measurements

Objective: To determine the effects of storage of arterial and venous blood samples in ice water on blood gas and acid-base measurements.Design: Prospective, in vitro, laboratory study.Setting: School of veterinary medicine.Subjects: Six healthy dogs.Measurements and main results: Baseline measurements of partial pressure of oxygen (PO2), partial pressure of carbon dioxide (PCO2), pH, hemoglobin concentration (tHb), oxyhemoglobin saturation, and oxygen content (ContO(2)) were made. Bicarbonate (HCO3) and standard base excess (SBE) were calculated. Arterial and venous blood samples were separated into 1 and 3 mL samples, anaerobically transferred into 3 mL plastic syringes, and stored in ice water for 6 hours. Measurements were repeated at 15, 30 minutes, and 1, 2, 4, and 6 hours after baseline measurements. Arterial (a) PO2 increased significantly from baseline after 30 minutes of storage in the 1 mL samples and after 2 hours in the 3 mL samples. Venous (v) PO2 was significantly increased from baseline after 4 hours in the 1 mL samples and after 6 hours in the 3 mL samples. The pHa significantly decreased after 2 hours of storage in the 1 mL samples and after 4 hours in the 3 mL samples. In both the 1 and 3 mL samples, pHv decreased significantly only after 6 hours. Neither the arterial nor the venous PCO2 values changed significantly in the 1 mL samples and increased only after 6 hours in the 3 mL samples. No significant changes in tHb, ContO(2), SBE, or HCO3 were detected.Conclusions: the PO2 of arterial and venous blood increased significantly when samples were stored in plastic syringes in ice water. These increases are attributable to the diffusion of oxygen from and through the plastic of the syringe into the blood, which occurred at a rate that exceeded metabolic consumption of oxygen by the nucleated cells.

Different fasting periods in tiletamine-zolezepam-anethetized cats: Glycemia, recovery, blood-gas and cardiorrespiratory parameters

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Hemogasometria de eqüinos submetidos à obstrução experimental do duodeno, íleo e cólon maior

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Efeitos do modo ventilatório sobre variáveis hemogasométricas em equinos submetidos à mudança de decúbito durante a anestesia geral inalatória com halotano

Compararam-se os efeitos da ventilação espontânea (V E) e controlada (V C) em equinos submetidos à mudança de decúbito durante anestesia. Dezesseis animais foram equitativamente divididos em dois grupos: V E e V C. Os procedimentos cirúrgicos foram iniciados com os animais em decúbito lateral esquerdo (DLE) e, após 75 minutos, os animais foram reposicionados em decúbito lateral direito (DLD). Análises hemogasométricas do sangue arterial foram realizadas após 30 e 75 minutos com os animais posicionados em cada decúbito (M1 e M2 no DLE e M3 e M4 no DLD, respectivamente). Durante a V E, observaram-se hipercapnia (PaCO2 >45mmHg), acidose respiratória (pH <7,35), redução significativa da oxigenação sanguínea após 75min da mudança de decúbito (M4: 205,8±124,7mmHg) em relação aos valores de PaO2 observados antes da mudança de posicionamento (M1: 271,8±84,8mmHg). A Vc foi associada a valores de PaCO2 e pH mais próximos da normalidade bem como resultou em valores de PaO2 significativamente maiores (52 a 96% de elevação nos valores médios) que a V E. Conclui-se que a mudança de decúbito, em equinos anestesiados com halotano e mantidos sob V E, resulta em hipercapnia, acidose respiratória e diminuição dos valores de PaO2. A instituição de V C, desde o início da anestesia, previne a acidose respiratória, além de resultar em valores de PaO2 mais próximos do ideal para animais respirando O2 a 100%.

Effect of remifentanil hydrochloride administered via constant rate infusion on the minimum alveolar concentration of isoflurane in cats

Objective - To evaluate the effects of increasing doses of remifentanil hydrochloride administered via constant rate infusion (CRI) on the minimum alveolar concentration (MAC) of isoflurane in cats. Animals - 6 healthy adult cats. Procedures - For each cat, 2 experiments were performed (2-week interval). On each study day, anesthesia was induced and maintained with isoflurane; a catheter was placed in a cephalic vein for the administration of lactated Ringer's solution or remifentanil CRIs, and a catheter was placed in the jugular vein for collection of blood samples for blood gas analyses. On the first study day, individual basal MAC (MAC Basal) was determined for each cat. On the second study day, 3 remifentanil CRIs (0.25, 0.5, and 1.0 μg/kg/min) were administered (in ascending order); for each infusion, at least 30 minutes elapsed before determination of MAC (designated as MAC R0.25, MAC R0.5, and MAC R1.0, respectively). A 15-minute washout period was allowed between CRIs. A control MAC (MAC Control) was determined after the last remifentanil infusion. Results - Mean ± SD MAC Basal and MAC Control values at sea level did not differ significantly (1.66 ± 0.08% and 1.52 ± 0.21%, respectively). The MAC values determined for each remifentanil CRI did not differ significantly. However, MAC R0.25, MAC R0.5, and MAC R1.0, were significantly decreased, compared with MAC Basal, by 23.4 ± 79%, 29.8 ± 8.3%, and 26.0 ± 9.4%, respectively. Conclusions and Clinical Relevance - The 3 doses of remifentanil administered via CRI resulted in a similar degree of isoflurane MAC reduction in adult cats, indicating that a ceiling effect was achieved following administration of the lowest dose.

Efeitos da correção da obesidade sobre os parâmetros cardiorrespiratórios em cães

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Integrated analysis of halogenated organic pollutants in sub-millilitre volumes of venous and umbilical cord blood sera

A rapid, robust and economical method for the analysis of persistent halogenated organic compounds in small volumes of human serum and umbilical cord blood is described. The pollutants studied cover a broad range of molecules of contemporary epidemiological and legislative concern, including polychlorobiphenyls (PCBs), polychlorobenzenes (CBs), hexachlorocyclohexanes (HCHs), DDTs, polychlorostyrenes (PCSs) and polybromodiphenyl ethers (PBDEs). Extraction and clean-up with n-hexane and concentrated sulphuric acid was followed with analysis by gas chromatography coupled to electron capture (GC-ECD) and GC coupled to negative ion chemical ionisation mass spectrometry (GC-NICI-MS). The advantages of this method rest in the broad range of analytes and its simplicity and robustness, while the use of concentrated sulphuric acid extraction/clean-up destroys viruses that may be present in the samples. Small volumes of reference serum between 50 and 1000 μL were extracted and the limits of detection/quantification and repeatability were determined. Recoveries of spiked compounds for the extraction of small volumes (≥300 μL) of the spiked reference serum were between 90% and 120%. The coefficients of variation of repeatability ranged from 0.1-14%, depending on the compound. Samples of 4-year-old serum and umbilical cord blood (n = 73 and 40, respectively) from a population inhabiting a village near a chloro-alkali plant were screened for the above-mentioned halogenated pollutants using this method and the results are briefly described. © 2010 Springer-Verlag.

Equilíbrio ácido-base e hidroeletrolítico em eqüinos com cólica

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)