ESTUDO DA UMIDIFICACAO E DO AQUECIMENTO DOS GASES INSPIRADOS DURANTE A VENTILACAO MECANICA NO CAO

The authors studied the effect of temperature and humidity of inhaled gases on the respiratory tract of dogs submitted to mechanic ventilation. According to these two variables, fourty dogs were divided in five groups: -G1: 22-26°C and 17-20 mg H2O.l-1; G2: 27-31°C and 23-27 mg H2O.l-1; G3: 32-36°C and 30-36 mg H2O.l-1; G4: 37-41°C and 40-49 mg H2O.l-1; G5: 42-46°C and 59-65 mg H2O.l-1. The following parameters were evaluated: medial arterial pressure, cardiac frequency, venous pressure of inferior cava (CVP), endotracheal pressure, arterial pH, PaO2, PaCO2, rectal temperature, and the histology of the tracheobronchial tree. In the groups G1 and G5, the endotracheal pressure and CVP presented a slight raise. In the groups G1, G2 and G3, there was no histological modification or progressive hypothermia. The group G5 presented metabolic acidosis and great histological alteration; in this group the rectal temperature remained stable. The group G4 presented great histological alteration and hypothermia. In conclusion, the temperature and humidity of inhaled gases should not be higher than 36°C and 36 mm H2O.l-1, respectively. However, the stability of body temperature only is achieved when the temperature of the inhaled air is 42°C or higher.

Chromosome sensitivity to bleomycin in G2 lymphocytes from Down syndrome patients

Several studies have demonstrated that lymphocytes from patients with Down syndrome (DS) exhibit an increased frequency of chromosome aberrations when they are exposed to ionizing radiation or to chemicals at the G0 or G1 phases of the cell cycle, but not at G2 when compared to normal subjects. To determine the susceptibility of DS lymphocytes at G2 phase, bleomycin, a radiomimetic agent, was used to induce DNA breaks in blood cultures from 24 Down syndrome patients. All the patients with DS showed free trisomy 21 (47,XX + 21 or 47,XY + 21). Individuals that showed an average number of chromatid breaks per cell higher than 0.8 were considered sensitive to the drug. No control child showed susceptibility to bleomycin, and among the 24 patients with DS, only one was sensitive to the drug. No significant difference was observed between the two groups, regarding chromatid break frequencies in treated G2 lymphocytes. The distribution of bleomycin-induced breaks in each group of chromosomes was similar for DS and controls. No significant difference was found in the response to bleomycin between male and female subjects. Probably, the main factor involved in chromosome sensitivity of lymphocytes from patients with DS is the phase of the cell cycle in which the cell is treated.

Is the Thoroughbred race-horse under chronic stress?

Thoroughbred fillies were divided into three groups according to age: group 1, 7 fillies aged 1 to 2 years (G1) starting the training program; group 2, 9 fillies aged 2 to 3 years (G2) in a full training program; group 3, 8 older fillies 3 to 4 years of age (G3) training and racing. Blood samples were collected weekly from July to December. Cortisol was quantified using a solid phase DPC kit. The intra- and interassay coefficients of variation were 12.5% and 15.65% and sensitivity was 1.9 ± 0.2 nmol/ l. The semester average of cortisol levels varied between groups: G1 = 148.8 ± 6.7, G2 = 125.7 ± 5.8, G3 = 101.1 ± 5.4 nmol/l, with G3 differing statistically from the other groups. The lower cortisol levels observed in the older fillies leads us to propose that the stress stimulus, when maintained over a long period of time, may become chronic and result in a reduction of hypophyseal corticotropin-releasing hormone receptors. The secretion of endogenous opioids may also lead to low serum cortisol levels.

Use of fibrin glue derived from snake venom in testicular biopsy of rams

Sequelae due to testicular biopsy such as hemorrhage, adhesion and fibrosis may be limiting factors to the use of this surgical procedure. Fibrin glue (FG) derived from snake venom was used to minimize these sequelae, as well as to evaluate its healing property in tunica vaginalis and scrotal skin of rams. Applicability of fibrin glue derived from snake venom was tested in different tissues of other animals such as in sciatic nerve and colon of rats and skin of rabbits. In the present study, 30 healthy adult rams were used. They were divided into 3 groups of 10 animals each as follows: G1: fibrin glue group (application of fibrin glue on puncture sites and skin incisions after bilateral testicular biopsy with a Tru-Cut needle); G2: swab/nylon group (hemostasis by compression with a swab on puncture sites and skin suturing with nylon after biopsy) and G3: control group (the animals were not subjected either to biopsy or to surgery). On the 20th day after biopsy, the presence of adhesion strands between the sites of skin incision and testicle was evaluated by palpation Adhesion strands were found in three testicles (15%) in G1 and in two testicles (10%) in G2. One hundred days after biopsy, orchiectomy was carried out and the material collected was assessed for subcutaneous (SC) and/or tunica vaginalis adhesions. G3 did not present any abnormality. Groups G1 and G2 presented four testicles each (20%) with adhesion between the tunics at biopsy site. On the other hand, subcutaneous adhesions were found once (5%) in G1 and three times (15%) in G2. Fibrin glue showed to be of easy application, required short postoperative monitoring, presented fast and good-quality healing property and tended to reduce formation of subcutaneous adhesion.

Efeitos de diferentes doses de tenoxicam sobre a medula espinhal e as meninges. Estudo experimental em caes

Background and Objectives. The analgesic actions of nonsteroidal anti-inflammatory drugs (NSAID) result from the inhibition of the peripheral synthesis of prostaglandins. In spite of the emphasis on the peripheral action, several studies have shown the potential central action of such drugs. In rats, NSAID doses insufficient to block pain when systemically administered were effective when intrathecally injected. This effect could be mediated by interaction with descending serotoninergic ways together with neurotransmission modulation of glycine or N-methyl-D-aspartate receptors. Our goal was to study the effect of different tenoxican doses in the histology of dogs spinal cord and meninges. Methods. Thirty two dogs (7 to 17 kg) were randomly distributed in four groups: G1 - Control with distilled water (DW); G2 - 2 mg tenoxican diluted in DW; G3 - 4 mg tenoxican diluted in DW; G4 - 10 mg tenoxican diluted in DW in a constant volume of 1 ml. Anesthesia was induced with etomidate and fentanyl and dural puncture was performed with a 25G spinal needle in interspace L6-7. Animals were observed for 72 hours and subsequently euthanized by electrocution. Lumbar and sacral spinal cord segments were removed for further histologic examination. Results. All animals were clinically normal during the observation period and there has been no histologic alteration of the nervous system and meninges. Conclusions. In our experimental model intrathecal tenoxican doses up to 10 mg have not triggered nervous tissue or meningeal injuries in dogs.

Comparacao da recuperacao de anestesia venosa com propofol e anestesia inalatoria com sevoflurano para laparoscopia ginecologica

Backgrounds and Objectives: Both continuous venous anesthesia with propofol and inhalational anesthesia with sevoflurane propitiate fast arousal with few side effects. The aim of this study was to compare the arousal and post anesthestic recovery times in patients submitted to these two agents. Methods: Forty three patient aged 18 to 50 years, physical status I or II, submitted to gynecological laparoscopy were distributed in two groups: G1 - propofol in continuous infusion of 115 μg.kg -1.min -1 and G2 sevoflurane. All the patients were pre-medicated with 7.5 mg midazolam, sufentanil 0.5 μg.kg -1, propofol 2 mg.kg -1, atracurium 0.5 mg.kg -1, N 2O in 50% of oxygen in a no-rebreathing system. The depth of the anesthesia and arousal time were assessed by the Bispectral index (BIS). The time between end of anesthesia and eye opening, time for command response and time for orientation were also evaluated. Results: The times recorded in minutes were: G1 - eye opening 8.2 ± 2.9, command response 8.6 ± 3.1, orientation 9.8 ± 3.4, recovery 31.6 ± 3.8; G2 - eye opening 4.5 ± 3, command response 4.9 ± 3.4, orientation 6.2 ± 3.4, recovery 66 ± 8. Except the recovery time, all the values were larger in G1. Conclusions: Both intravenous propofol or inhalational sevoflurane were considered excellent anesthetic techniques as to recovery time and recovery room discharge. Sevoflurane provided an earlier arousal with a longer recovery room stay as compared to propofol.

Tracheobronchial consequences of the use of heat and moisture exchangers in dogs

Purpose: To determine the effect of heat and moisture exchange (HME) on the tracheobronchial tree (TBT) using a unidirectional anesthesic circuit with or without CO2 absorber and high or low fresh gas flow (FGF), in dogs. Methods: Thirty-two dogs were randomly allocated to four groups: G1 (n = 8) valvular circuit without CO2 absorber and high FGF (5 L·min-1); G2 (n = 8) as G1 with HME; G3 (n = 8) circuit with CO2 absorber with a low FGF (1 L·min-1); G4 (n = 8) as G3 with HME. Anesthesia was induced and maintained with pentobarbital. Tympanic temperature (TT), inhaled gas temperature (IGT), relative (RH) and absolute humidity (AH) of inhaled gas were measured at 15 (control), 60, 120 and 180 min of controlled ventilation. Dogs were euthanized and biopsies in the areas of TBT were performed by scanning electron microscopy. Results: The G2 and G4 groups showed the highest AH (>20 mgH2O·L-1) and G1 the lowest (< 10 mgH2O·L-1) and G3 was intermediate (<20 mgH2O·L-1) (P < 0.01). There was no difference of TT and IGT among groups. Alterations of the mucociliary system were greatest in G1, least in G2 and G4, and intermediate in G3. Conclusion: In dogs, introduction of HME to a unidirectional anesthetic circuit with/without CO2 absorber and high or low FGF preserved humidity of inspired gases. HME attenuated but did not prevent alterations of the mucociliary system of the TBT.

Titulacao do sevoflurano utilizando o indice bispectral em anestesia pediatrica. Influencia da medicacao pre-anestesica no tempo de despertar e no consumo de anestesico inalatorio

Background and Objectives - Sevoflurane is an inhalational anesthetic drug with low blood/gas solubility providing fast anesthesia induction and emergence. Its ability to maintain cardiovascular stability makes it ideal for pediatric anesthesia. The aim of this study was to evaluate hemodynamic stability, consumption of inhalational anesthetics and emergence time in children with and without premedication (midazolam or clonidine) anesthetized with sevoflurane titrated according to BIS monitoring. Methods - Participated in this study 30 patients aged 2 to 12 years, physical status ASA I, undergoing elective surgeries who were divided into 3 groups: G1 - without premedication, G2 - 0.5 mg.kg-1 oral midazolam, G3 - 4 μg.kg-1 oral clonidine 60 minutes before surgery. All patients received 30 μg.kg-1 alfentanil, 3 mg.kg-1 propofol, 0.5 mg.kg-1 atracurium, sevoflurane in different concentrations monitored by BIS (values close to 60) and N2O in a non rebreathing system. Systolic and diastolic blood pressure, heart rate, expired sevoflurane concentration (EC), sevoflurane consumption (ml.min-1) and emergence time were evaluated. Emergence time was defined as time elapsed between the end of anesthesia and patients' spontaneous movements trying to extubate themselves, crying and opening eyes and mouth. Results - There were no differences among groups as to systolic and diastolic blood pressure, EC, sevoflurane consumption and emergence time. Heart rate was lower in G3 group. Conclusions - Sevoflurane has provided hemodynamic stability. Premedication with clonidine and midazolam did not influence emergence time, inhaled anesthetic consumption or maintenance of anesthesia with sevoflurane. Anesthesia duration has also not influenced emergence time. Hypnosis monitoring was important for balancing anesthetic levels and this might have been responsible for the similarity of emergence times for all studied groups.

Efeitos do alopurinol em rins isquemicos de caes anestesiados com pentobarbital sodico

Background and Objectives - Allopurinol is a drug which inhibits the formation of noxious renal free radicals. The aim of this study was to evaluate the protecting renal effects of allopurinol in ischemic kidneys of dogs. Methods - Sixteen dogs were anesthetized with sodium pentobarbital and submitted to extracellular volume expansion (1.4 ml.kg-1.min-1), to mechanic ventilation with air, to right nephrectomy and to left renal artery clamping. Changes which might occur in renal morphology and function after 30 min of total ischemia and posterior reperfusion were studied in Group 1 (G1), in addition to the action of allopurinol (50 mg.kg-1) on those kidneys, when administered 24 h before the experiment and 1 h before the ischemic procedure in Group 2 (G2). The following parameters: heart rate, inferior vena cava pressure, mean blood pressure, PAH clearance (PAH(c)), renal blood flow (RBF), renal vascular resistance (RVR), creatinine clearance (Cr(c)), filtration fraction, urine output, plasma and urine osmolality, osmolar clearance, free water, sodium and potassium clearance, urine and fractional sodium and potassium excretion, hematocrit, rectal temperature, and left kidney histology were evaluated in four moments: M1 control, and M2, M3, M4 obtained immediately, 15 and 30 min after unclamping of the left renal artery. In G2, M1, M2, M3 and M4 were obtained 45, 90, 105, and 120 min after the second allopurinol dose. Results - Both groups showed the highest values for PAH(c), RBF, and Cr(c), and the lowest values for RVR in M1. Animals were tachycardiac since the beginning of the experiment both in G1 and in G2. The other parameters were not changed. Left kidney histological evaluation showed alterations compatible with acute tubular necrosis in both experimental groups. Conclusions - Alterations found in renal hemodynamics were compatible with the release of vasoconstrictor substances due to renal ischemia. Allopurinol was not effective in preventing renal alterations caused by ischemia and reperfusion.

Evaluation of intraocular and partial CO2 pressure in dogs anesthetized with propofol

The effects of propofol on intraocular pressure (IOP) and end tidal CO2 (ETCO2) were studied because an elevation in the latter may alter IOP. Twenty dogs were divided into two groups (G1 and G2). G1 dogs were induced with 10 mg/kg (IV) of propofol followed by a 0.4 mg/kg/min continuous infusion of the same agent diluted in a 0.2% dextrose solution for 1 h. G(CAPS) 2 dogs served as the control group, where only dextrose solution was administered, under the same time intervals as in G1. Applanation tonometry (Tono-Pen) was used to determine IOP and ETCO2 as a method to determine partial CO2 pressure. Measurements were taken every 15 min for 1 h, with M1 occurring immediately before IV administration. IOP and ETCO2 were not statistically significant in either groups. Based on the results, it may be concluded that propofol does not alter IOP and ETCO2.

Análise das vantagens de duas técnicas anestésicas - Venosa e inalatória - Para colecistectomia por videolaparoscopia

Background and Objectives - It is essential to reduce health care costs without impairing the quality of care. Propofol is associated to faster recovery and it is known that post-anesthesia care unit (PACU) costs are high. The aim of this study was to evaluate the advantages of two anesthesia regimens - propofol continuous infusion or isoflurane - taking into account the cost of both techniques on PACU stay. Methods - Forty seven patients, physical status ASA I, II and III, undergoing laparoscopic cholecystectomy were divided into 2 groups according to the anesthetic agent: G1, conventional propofol continuous infusion (100-150 μg.kg-1.min-1) and G2, isoflurane. All patients were induced with sufentanil (1 μg.kg-1) and propofol (2 mg.kg-1) and were kept in a re-inhalation circuit (2 L.min-1 of fresh gas flow) with 50% N2O in O2, sufentanil (0.01 μg.kg-1.min-1) and atracurium (0.5 mg.kg-1), or pancuronium (0.1 mg.kg-1) for asthma patients. All patients received atropine and neostigmine at the end of the surgery. Prophylactic ondansetron, dipyrone and tenoxican were administered and, when necessary, tramadol and N-butylscopolamine. Costs of anesthetic drugs (COST), total PACU stay (t-PACU), and PACU stay after extubation (t-EXT) were computed for both groups. Results - Costs were significantly lower in the isoflurane group but t-PACU was 26 minutes longer and t-EXT G1G1 only. Therefore, in G1, t-PACU was a function of propofol doses. Conclusions - We concluded that the use of isoflurane as anesthesia maintenance agent for laparoscopic cholecystectomy showed lower drug costs as compared to propofol. However, isoflurane group patients stayed longer in PACU as compared to propofol continuous infusion group.

Estudo comparativo das complicações terapêuticas no Lúpus Eritematoso Sistêmico e nas glomerulopatias idiopáticas.

PURPOSE: To evaluate the therapeutic complications due to the use of immunosupressors in patients with nephropathy. METHODS: 76 patients who had used steroids and cyclophosphamide were retrospectively studied. The cases were divided into three groups: G1= 15 patients with Systemic Lupus Erythematosus without renal lesion; G2= 33 patients with lupus nephritis and G3= 28 patients with nephrotic syndrome owing to idiopathic glomerulopathy. RESULTS: There were no differences related to time of follow up (G1= 42.4 +/- 51, G2= 52.3 +/- 51, G3= 41.8 +/- 47.8 months), total used dosage of steroids (G1= 20, G2= 28, G3= 16 grams) and time of drug use (G1= 20, G2= 26, G3= 14.5 months). About cyclophosphamide use, there was no difference in the percentage of patients who used it (13% in G1, 51% in G2, 28% in G3), but the patients from G1 received lower total dosage than those from G2 (p<0.05). Cushingoid appearance, epigastric distress, psychiatric disorders, diabetes mellitus and ocular alterations occurred in all the three groups, with no statistically significant differences. The infections complications, those considered more severe clinically, were more frequent in G2 (G1= 6%, G2= 15%, G3= 0% - p<0.05), the same occurring with the deaths (7% in G1, 30% in G2, 0% in G3 - p<0.05). CONCLUSION: In patients with lupus nephritis there were more infections complications owing to prolonged immunosuppresion what may indicate a severity marker of this type of lesion.

Avaliações bioquímicas séricas e hepáticas do extrato de yacon (Polymnia sonchifolia) Poepp. & Endl.

Yacon is a medicinal plant, the tuberous roots of which have been thought to contain a large amount of fructan (oligosaccharides). Purpose - The aim of paper was to study the effect of aqueous extracts of yacon on biochemical parameters of clinical importance in rats. The animals (male, wistar, weighing approximately 300g) were divided in 3 groups: G1(n=8)= water control; G2(n=8)= aqueous extract of roots (0,17g/100g/day); G3(n=8)= aqueous extract of leaves (25mg/100g/day). The serum samples were obtained after 30 days, and the biochemical parameters were measured. The livers were removed and homogenized in 0,01M phosphate buffer pH 7,0 and then the supernatant fractions were used for enzyme assay. Significantly increased serum glucose was observed in G2 (206,72±91,27 mg/dL). The groups G2 and G3 rats had higher (p<0,05) urea concentration, while creatinin level decreased (p<0,05). The serum albumin concentration showed a tendency to remain in G2 (2,44±0,45 g/dL) and G3 (2,84±0,50 g/dL). Aqueous extracts administration markedly decreased (p<0,05) the activities of ALT in the liver and greatly increased these enzymatic activities in blood. The serum alkaline phosphatase activity increased (p<0,05) in rats receiving the aqueous extract of root (192,75±20,95 U/dL), while aqueous extract of leaves reduced it (129,57±19,93 U/dL). The results indicated that the extract of yacon promoted changes of the biochemical parameters.

Avaliação bioquímica do extrato etanólico de própolis em ratos

Propolis is a natural product collected by honey bees containing, among other biochemical constituents, a variety of flavonoids. Propolis is a folk medicinal employed for treating various diseases. It is alleged to exhibit a broad spectrum of bioactivities. The aim of this study was to evaluate the effect of ethanolic extract of propolis (EEP) of species Plebeia droryana and Scaptotrigonea bipunctata through biochemical parameters. Rats were divided into 4 groups: (G1) untreated; (G2) ethanol treated; (G3) treated EEP of Plebeia droryana; (G4) treated of Scaptotrigonea bipunctata. The EEP (100 mg/kg b. w., daily) was administered orally to the animals, for 30 days. Treatment with EEP for two species showed reduction (p<0,05) in serum alanine aminotransferase, aspartato aminotransferase and alkaline phosphatase activity, compared to control ethanol values. The administration of EEP lowered significantly the serum levels of cholesterol (G3= 48,83±5,7 mg/dL; G4=56,91±6,5 mg/dL) and triacylglycerol (G3=45,17±4,16 mg/dL; G4=46,74± 3,90 mg/dL). The serum concentration of albumin (G3=4,16±0,6 g/dL; G4= 3,61±0,36 g/dL) increased (p<0,05) after the administration of EEP, however, it did not affect total protein and glucose concentration. The data suggest that EEP of two species caused alterations of the biochemical parameters.

Evaluation of marginal microleakage in Class II cavities: Effect of microhybrid, flowable, and compactable resins

Objective: The goal of the present study was to evaluate the microleakage on the cementum/dentin and enamel surfaces in Class II restorations, using different kinds of resin composite (microhybrid, flowable, and compactable). Method and materials: Forty human caries-free molars were extracted and selected. Eighty Class II standardized cavities were made in the cervical wall at the cementoenamel junction (CEJ) and at the mesial and distal surfaces. The teeth were divided into four groups: G1 - adhesive system + microhybrid resin composite Z100; G2 - adhesive system + compactable resin composite Prodigy Condensable; G3 - adhesive system + flowable resin composite Revolution + Z100 resin composite; G4 - adhesive system + Revolution fluid resin + compactable resin composite Prodigy Condensable. The adhesive system used in this study was Scotchbond Multi-Purpose Plus. The specimens were thermocycled in baths of 5°C and 55°C for 1,000 cycles and immersed in 50% silver nitrate solution. The specimens then were sectioned and evaluated on degree of dye penetration. Results: The results were evaluated using the nonparametric Kruskall-Wallis test, which showed a statistically significant difference between groups G1 and G4, G2 and G4, and G3 and G4. Conclusions: None of the materials was able to eliminate the marginal microleakage at the cervical wall; the application of a low-viscosity resin composite combined with a compactable resin composite significantly decreased the microleakage.