Avaliação do fluxo de saída do ventrículo esquerdo em gatos anestesiados submetidos ao pneumoperitônio e à posição deTrendelenburg / Evaluation left ventricle Outflow in cats anesthetized submitted to pneumoperitoneum and Trendelenburg position

Objetivou-se avaliar os efeitos do pneumoperitônio e da posição de Trendelenburg sobre o fluxo de saída do ventrículo esquerdo em gatos anestesiados. Quatorze gatos foram alocados aleatoriamente em dois grupos, ambos submetidos ao pneumoperitônio com 10mmHg de dióxido de carbono (CO2). No grupo controle (GC n=7), os animais foram submetidos apenas ao pneumoperitônio e, no grupo Trendelenburg (GTREN n=7), os animais foram colocados em cefalodeclive 20° após o pneumoperitônio. A indução anestésica foi realizada com isoflurano, utilizando-se caixa de indução. Posteriormente, os animais foram mantidos sob anestesia inalatória com o mesmo fármaco. Foram avaliados a velocidade do fluxo de saída do ventrículo esquerdo (VFSVE), os gradientes máximo (GmáxSVE) e médio (GmédSVE) de pressão e a integral velocidade-tempo (IVT). Os parâmetros foram mensurados nos momentos T0 (basal), antes da insuflação; T5 (cinco), T15 (quinze) e T30 (trinta) minutos após a insuflação. Os resultados mostraram um aumento da VFSVE no GC, em T15 e T30 (P=0,024), e um aumento do GmáxSVE no GC, em T30 (P=0,045). As variáveis não se alteraram significativamente em nenhum momento no GTREN. Dessa forma, conclui-se que a posição de Trendelenburg favoreceu o sistema cardiovascular, preservando os índices de fluxo sanguíneo na saída do ventrículo esquerdo.(AU)

The aim of this study was to evaluate the effects of pneumoperitoneum and Trendelenburg position on the left ventricular outflow in anesthetized cats. Fourteen cats were randomly divided into two groups, both submitted to pneumoperitoneum of 10 mmHg with carbon dioxide (CO2), and in the control group (GC n = 7) the animals were subjected only to pneumoperitoneum and the Trendelenburg group (n = 7 GTREN) the animals were placed in cefalodeclive 20° after pneumoperitoneum. Anesthesia of the animals was performed with isoflurane using induction box, keeping the animals under inhalation anesthesia with the same drug. We evaluated the speed of the left ventricular outflow (VFSVE), the maximum pressure gradient (GmáxSVE), mean pressure gradient (GmédSVE) and velocity-time integrals (IVT). The parameters were measured in time, T0 (baseline), before the insufflation; T5 (five); T15 (fifteen) and T30 (thirty) minutes after inflation. The results showed an increase in VFSVE in GC, T15 and T30 (p = 0,024) and an increase in GmáxSVE in GC in T30 (p = 0,045). The variables did not change significantly at any time in GTREN. Thus, it is concluded that the Trendelenburg position favored the cardiovascular system, preserving blood flow rates in the left ventricular outflow.(AU)

Cardiopulmonary and sedative effects of intravenous or epidural methadone in conscious dogs.

Cardiopulmonary and sedative effects of intravenous or epidural methadone were compared. Six beagles were randomly assigned to group MIV (methadone 0.5 mg/kg IV + NaCl 0.9% epidurally) or MEP (methadone 0.5 mg/kg epidurally + NaCl 0.9% IV). Cardiopulmonary, blood gas and sedation were assessed at time (T) 0, 15, 30, 60, 120, 240 and 480 min after drug administration. Compared to T0, heart rate decreased at T15-T120 in MIV (p < .001) and T15-T240 in MEP (p < .05); mean arterial pressure was reduced at T15-T60 in MEP (p < .01); respiratory rate was higher at T15 and T30 in both groups (p < .05); pH was lower at T15-T120 in MIV (p < .01) and T15, T30 and T120 in MEP (p < .05); PaCO2 was higher at T15-T60 in MIV (p < .01) and T15, T30 and T120 in MEP (p < .01); sedation scores were higher at T15 and T30 in MIV and T15-T60 in MEP (p < .05). At T120 and T240, sedation score was higher in group MEP compared with group MIV (p < .01) In conclusion, cardiopulmonary and sedative effects of identical methadone doses are similar when administered IV or epidurally to conscious healthy dogs.

Avaliação do perfil eletrocardiográfico pré e trans-anestesia em lobos-guará / Evaluation of electrocardiographic profile pre and trans-anesthesic in maned wolves

O presente estudo tem como objetivo avaliar o efeito da administração do Zolazepam/Tiletamina nas funções cardiorrespiratórias e eletrocardiográficas em lobos-guará (Chrysocyon brachyurus) mantidos em cativeiro. Foram utilizados dez lobos-guará clinicamente saudáveis (seis machos e quatro fêmeas), com média de peso 23,5±3,5kg, e idade de 6,5±2,8 anos. Os lobos eram mantidos em cativeiro e foram capturados pelos tratadores, proporcionando o mínimo de estresse possível para avaliação dos parâmetros pré-anestésicos. Foram avaliadas frequência cardíaca e respiratória, temperatura retal, pressão arterial média e eletrocardiografia. Após coleta dos parâmetros fisiológicos e eletrocardiográficos pré-anestesia, foi administrada a dose de 5,1±0,7mg/kg de Zolazepam/Tiletamina intramuscular. Depois da anestesia, colocaram-se os eletrodos do eletrocardiograma nos membros torácicos e pélvicos. Os animais eram monitorados durante uma hora, sendo que, a cada 10 minutos, era realizado o registro dos valores eletrocardiográficos, assim como os valores dos parâmetros fisiológicos e cardiorrespiratórios. Os resultados mostraram alteração significativa na amplitude da onda P entre 10 a 50 minutos pós-anestesia. Frequência cardíaca (153±20bmp), frequência respiratória (29±6mpm), temperatura corporal (38,4±1oC), pressão arterial média (114±20mmHg) e as outras variáveis eletrocardiográficas não apresentaram alterações. O aumento da amplitude da onda P nos animais deste trabalho sugeriu um aumento atrial, oriundo de doenças cardíacas ou simplesmente pelo aumento da frequência cardíaca durante a contenção.

The aim of this study was to assess the effects of the anesthetic combination of Tiletamine/Zolazepam on the cardiorespiratory function and electrocardiographic profile in captive maned wolves (Chrysocyon brachyurus). Ten maned wolves were used in this study (6 males and 4 females). All animals were healthy, with an average body weight of 23.5±3.5kg, and age of 6.5±2.8years. The wolves were conditioned to be physically restrained by their keepers in order to minimize stress during assessment of pre-anesthetic parameters. Data on heart and respiratory rates, rectal temperature, mean arterial blood pressure and electrocardiography were collected. Pre-anesthetic physiological an eletrocardiographic parameters were collected before the administration of 5.1±0.73mg/kg Tiletamine/Zolazepam intramuscularly. Under anesthesia, electrocardiogram electrodes were placed on thoracic and pelvic limbs and eletrocardiographic data was recorded every 10 minutes for approximately one hour, totaling 6 electrocardiograms. Heart rate 153±20bmp, respiratory rate 29±6mpm, rectal temperature 38,4±1oC, mean arterial blood pressure 114±20mmHg, and the other electrocardiographic parameters did not change; however, the P wave amplitude changed from 10 to 50 minutes after anesthesia. The increase in the P wave on the animals in this study suggested an atrial increase, probably due to cardiac disease or just by increasing the heart rate during the capture.

Use of dexamethasone and granisetron in the control of delayed emesis for patients who receive highly emetogenic chemotherapy. National Cancer Institute of Canada Clinical Trials Group.

PURPOSE: To evaluate the roles of granisetron and dexamethasone for emesis control on days 2 through 7 after the administration of cisplatin in doses of 50 mg/m2 or greater to patients who had not previously received chemotherapy. PATIENTS AND METHODS: Four hundred thirty-five eligible and assessable patients were randomized to one of two arms in a double-blind fashion: arm A; granisetron 3 mg intravenous (i.v.) plus dexamethasone 10 mg i.v. prechemotherapy followed by granisetron 1 mg orally at 6 and 12 hours, then granisetron 1 mg orally and dexamethasone 8 mg orally twice daily on days 2 through 7 (219 patients); arm B; as in arm A but with placebo substituted for granisetron on days 2 through 7 (216 patients). All patients completed diaries in which episodes of emesis and severity of nausea were recorded. RESULTS: The addition of granisetron on days 2 through 7 had no discernable impact on nausea and vomiting during this period. CONCLUSION: The administration of a 5-hydroxytryptamine3, receptor (5-HT3) antagonist, in this case granisetron, after 24 hours conferred no benefit. This negative result needs to be assessed in light of conflicting literature, but at present it does not appear that the routine use of these drugs in this setting is justified.

Random amplification of polymorphic DNA reveals serotype-specific clonal clusters among enterotoxigenic Escherichia coli strains isolated from humans.

The genetic diversity of 47 enterotoxigenic Escherichia coli (ETEC) strains of serotypes O6:H16, O27:H7, O29:H21, O128ac:H12, and O153:H45, previously isolated from diarrheic patients in Brazil over a period of 15 years, was investigated by random amplification of polymorphic DNA (RAPD). Informative band arrays were obtained with three 10-mer primers with G+C contents of 50, 60, and 70%. Based on the combination of the band profiles generated by the three primers 22 RAPD types were detected, and 5 major clonal clusters, each one with at least 80% identical bands, were established. The clonal clusters corresponded to strains having the same serotype which, in most cases, also had the same virulence factors (colonization factors and toxin types) and outer membrane protein and lipopolysaccharide sodium dodecyl sulfate-polyacrylamide gel electrophoresis profiles. The results suggested a correlation between phenotypic properties and genetic relatedness of ETEC isolates of human origin and indicated that a reduced number of clonally related strains are found in areas of ETEC endemicity in Brazil. Moreover, the RAPD technique revealed intraserotype-specific variations, undetectable by the combination of several phenotypic typing methods, among the ETEC strains analyzed. These results show that RAPD typing represents a useful tool for population genetics as well as for epidemiological studies of ETEC.

Cost comparison of recombinant human erythropoietin and blood transfusion in cancer chemotherapy-induced anemia.

OBJECTIVE: To compare the cost of recombinant human erythropoietin (rHuEPO) with that of blood transfusion in the treatment of chemotherapy-induced anemia from a healthcare system perspective. DESIGN: A decision analytic model. Baseline estimates were obtained from a review of clinical trials data and economic evaluation studies. SUBJECTS: Secondary data analyses of patients with advanced malignancies, excluding hematologic malignancies and metastasized solid tumors. INTERVENTIONS: Patients received either leukocyte-depleted packed red blood cells (PRBCs) or rHuEPO 150 units/kg s.c. three times per week for 6 months (24 wk). After 6 weeks, if rHuEPO recipients did not display a response, they received rHuEPO 300 units/kg s.c. three times weekly for the duration of therapy. If rHuEPO recipients still exhibited no response, they were given blood transfusions. MEASUREMENTS AND MAIN RESULTS: For a treatment period of 24 weeks, approximately 64% of rHuEPO recipients responded at an average expected cost of $12971 per patient. One hundred percent of transfusion recipients responded at a cost of $481; this resulted in a cost savings of $8490. Variation of response rates for rHuEPO or PRBCs did not appreciably lower costs. Lower rHuEPO dosages and higher numbers of transfused units of PRBCs yielded approximately equivalent costs; however, these strategies may not be clinically prudent. CONCLUSIONS: From a healthcare system cost and outcome perspective, blood transfusion is the preferred strategy for chemotherapy-induced anemia. However, rHuEPO may be considered an effective blood-sparing alternative for patients with non-stem cell disorders. Future cost-effectiveness analyses are needed to assess more completely both the clinical and quality-of-life benefits rHuEPO may contribute to individual patients' lives and to society overall.

Relationship between outer membrane protein and lipopolysaccharide profiles and serotypes of enterotoxigenic Escherichia coli isolated in Brazil.

The electrophoretic profiles of outer membrane proteins and lipopolysaccharide of sixty-five enterotoxigenic Escherichia coli of different serotypes and virulence-associated factors, toxin and colonization factors were determined. A close relationship between serotype and outer membrane protein and lipopolysaccharide patterns could be observed. No correlation could be found between the electrophoretic profiles and the expression of virulence-associated factors. The observed homogeneity of outer membrane protein and lipopolysaccharide profiles suggested the presence of only a few clones in the samples studied, and supported the use of outer membrane protein and lipopolysaccharide analysis as a useful epidemiological tool in the characterization of enterotoxigenic Escherichia coli isolates.

Strategic management of therapeutic advances: experience with colony-stimulating factors.

Recent therapeutic advances offer significant opportunities for improved patient outcomes while challenging our ability to deliver these outcomes in a cost-effective manner. This report describes the strategies for managing such advanced therapies--specifically, the recently introduced colony stimulating factors (CSFs)--that have been adopted at Cedars-Sinai Medical Center. Based on the principles of Continuous Quality Improvement (CQI), our approach begins with a multidisciplinary task force that develops and continuously refines guidelines for use of these agents. To provide immediate feedback when physician orders do not conform to the guidelines, the pharmacist notifies a physician expert, who promptly contacts the prescriber for a discussion of the case and how the guidelines do or do not apply. Since the introduction of CSFs, cost per admission has declined from $983 to $729 (26%) for oncology patients and from $737 to $281 (62%) for HIV patients. Although it is impossible to rigorously establish how much of this decrease has resulted from our proactive management strategy, costs have consistently decreased following each task force intervention.

Prospective physician review of orders for colony-stimulating factors.

A program is described in which physicians prospectively review orders for the use of colony-stimulating factors (CSFs) at a tertiary-care private teaching hospital. Hospital officers and administrators and the heads of medical subspecialties were presented with three options for managing the use of CSFs. Prospective review by physicians was selected, and a task force of medical subspecialists was established to develop criteria for use and to review orders. Initially, every order was prospectively reviewed, but criteria were developed under which some orders do not require physician review. CSF use is documented retrospectively by a drug-use evaluation pharmacist and reviewed for appropriateness by the physician task force. Between March and October 1991, 115 patients were given courses of CSFs, and the use of the physician review system resulted in appropriate use of the drugs for 98% of the oncology patients and 61% of the patients infected with the human immunodeficiency virus. The prospective physician reviewer system has been accepted by the medical staff at the facility and has helped to ensure appropriate use of CSFs.

N-methyl-D-aspartate-evoked release of acetylcholine from the medial septum/diagonal band of rat brain.

N-Methyl-D-aspartate (NMDA)-evoked release of [3H]acetylcholine (ACh) from slices of rat brain medial septum/vertical limb of the diagonal band (ms/vdB) was examined. NMDA increased the release of tritium in a concentration-dependent manner and the specific non-competitive NMDA antagonist, MK-801, and the competitive NMDA antagonist kynurenic acid inhibited this release. Tetrodotoxin inhibited the NMDA-evoked release suggesting the [3H]ACh released arises from collaterals of the cholinergic septohippocampal neurons. Basal release of tritium was significantly increased by glycine alone and strychnine inhibited this response while having no effect on NMDA-evoked release. However, glycine, although not affecting the NMDA-evoked release, did enhance release of tritium in the presence of NMDA and blocking concentrations of Kynurenic acid. Together, these findings suggest that under the conditions of these experiments sufficient concentrations of glycine permit the full expression of NMDA-evoked modulation of [3H]ACh release, and that the predominant actions of glycine were mediated by a specific, strychnine-sensitive receptor.

Influence of enteral feedings on phenytoin sodium absorption from capsules.

The influence of enteral feedings (with Ensure) on the absorption of phenytoin sodium from capsules was studied. Six healthy adult volunteers were given a single dose of phenytoin capsules 400 mg po on two occasions. Blood specimens were collected for 48 hours after each dose. In a randomized, crossover fashion, each subject completed the following two phases: (1) phenytoin without enteral feedings, and (2) concomitant enteral feedings before phenytoin and continued at 100 ml/h for ten hours. The areas under the concentration versus time curves from 0-48 hours (AUC0-48) were not significantly different between the two phases (p greater than 0.5). The percent relative bioavailability of phenytoin with enteral feedings was 101.7 percent. This study suggests that enteral feedings do not affect the serum concentrations of phenytoin after a single dose given in capsule form.

Acute ethanol treatment modifies response properties and habituation of the DR-VR reflex in the isolated frog spinal cord.

Ethanol modification of habituation, a fundamental form of behavioral plasticity, was examined in the isolated frog spinal cord preparation. The polysynaptic dorsal root to ventral root (DR-VR) reflex response was assessed in normal Ringer's and at one of four ethanol concentrations. The reflex itself was facilitated at lower levels (0.025%) and depressed at higher levels (0.05-0.5%) of ethanol. Habituation, decrement of the polysynaptic ventral root response to repeated dorsal root stimulation, was reduced at all ethanol concentrations. Understanding the mechanisms of ethanol action involved in the disruption of simple forms of plasticity will help us to explain its actions on more complex forms of associational processes.