Browsing by Author "Serpa, Priscila B. S."

Now showing 1 - 10 of 10
  • Thumbnail Image
    Blood Gas Tension Changes in Dogs Anesthetized with Two Different Oxygen Flow Rates Using a Nonrebreathing Bain Anesthetic System
    Natalini, Claudio Corrêa; Futema, Fábio; Serpa, Priscila B. S.; Nogueira Estrella, Jose Pedro; Pires, Jefferson da Silva D. S. (Universidade Federal do Rio Grande do Sul, 2010-01-01)
    Background: The non-rebreathing anesthetic system is one of the most used in veterinary medicine in small animals due to the low resistance to breathing. The Bain System is constructed with one corrugated external hose, one internal conducting duct for fresh gases, an optional pop-off valve and two connections (one for the breathing bag and the other for the patient). According to the literature recommendations, this system requires an oxygen flow rate between 130-200 mL/kg/min. This present work aims to evaluate the arterial blood gases tension changes in dogs anesthetized with two different oxygen flow rates (100 mL/kg/min or 200 ml/kg/min) using a nonrebreathing Bain System, in adult healthy dogs. Materials, Methods & Results: Fourteen adult healthy mongrel dogs (10 males and 4 females) ranging from 3.5 to 4.5 years old, with average body weight of 12.5 + 0.81 kg, were submitted to preanesthetic medication with acepromazine maleate (0.1 mg/kg IM) and fentanyl citrate (5 mcg/kg IM) and after 15 min induction of anesthesia was performed using sodium thiopental (9 mg/ kg, IV). An anesthetic state using the Bain System was maintained using oxygen 100 mL/kg/min and isoflurane 1.5 V% in group I and oxygen 200 mL/kg/min and isoflurane 1.5V% in group II. Heart and respiratory rates, oxygen saturation, arterial pH, blood gases and bicarbonate were the variables analyzed after induction and before intubation (T0), immediately after intubation (T1), at 10 min of anesthesia (T2), at 20 min of anesthesia (T3), at 30 min of anesthesia (T4), at 40 min of anesthesia (T5), at 50 min of anesthesia (T6), and after 60 min of anesthesia in the end of the procedure (T7). The results indicated that animals submitted to both protocols showed a significant decrease in arterial pH values from T1 to T7 in relation to T0. The differences found between the values from times T1 to T7 were statistically significant between them. The values of PaCO2 demonstrated statistically significant differences from T1 to T7 in both protocols. Protocol I showed statistically significant difference between T0 with respect to the times T1 to T7. For the parameter PaO2 there were statistically significant differences between protocols in T0 and not from T0 in comparison with T1 to T7 in both protocols. However, there were no significant differences between protocols due to inhalation of pure O2, that even using different flows causes an increase in PaO2The values of heart rate showed significant differences from T1 to T7 between protocols I, and protocol II. The values of base excess, O2 saturation and respiratory rate showed no statistically significant between protocols and time points. Discussion: Oxygen flow rate is the mean by which the CO2 is eliminated from nonrebrathing systems. Higher flow rates than those used in circle anesthetic systems are recommended in order to avoid carbon dioxide rebreathing within the nonrebrathing system. In our study we did demonstrate that the use of oxygen flow rate of 200 mL/kg/min with a Bain system kept the blood gas values and pH within acceptable range in healthy dogs submitted to general anesthesia with isoflurane 1.5V%. A lower flow rate of 100 mL/kg did produce arterial hypercapnia and academia of respiratory origin. The explanation for such result is probably due to the physical property of the inhalant anesthetic carrier gas flow. The use of higher flow rates will force exhaled carbon dioxide through the pop off valve, reducing its absorption. According to our findings a flow rate of 200 mL/kg/min should be recommended for the Bain system in dogs.
  • Thumbnail Image
    Cage-Free Pullets Minimally Affected by Stocking Density Stressors
    Abraham, Meagan E.; Robison, Cara I.; Serpa, Priscila B. S.; Strandberg, Natalia J.; Erasmus, Marisa A.; Fraley, Gregory S.; Erf, Gisela F.; Karcher, Darrin M. (MDPI, 2024-05-20)
    Management choices during the pullet phase can affect behavior, welfare, and health later in life, but few studies have evaluated the pullet phase, particularly in extensive housing systems. This study was a 2 × 2 factorial randomized complete block design (RCBD) with two strains and two stocking densities. The Lohmann LB-Lite and Lohmann LSL-Lite were housed on the floor at high-stocking density (619–670 cm2/bird) and low-stocking density (1249–1352 cm2/bird), which changed with age from 2 to 16 weeks of age (WOA). Bird-based measures of appearance, blood parameters, organ measurements, and production values were evaluated. Stocking density alone affected (p < 0.05) only relative bursal weight (% of body weight)—3.32% in the low-density versus 3.08% in the high-density group. High-stocking density was correlated with decreased uniformity (high—89.33 ± 0.24%; low—90.41 ± 0.24; p < 0.02) and worse feather coverage in the brown strain. High-stocking density was correlated with greater uniformity (High—90.39 ± 0.24%; Low—88.47 ± 0.24%; p < 0.001) and better feather coverage in the white strain. This study’s feed conversion ratio (FCR) was improved by 0.07 in the low-stocking density for both strains. The remaining parameters were affected by strain and age only. Thus, while stocking density effects vary slightly depending on the strain used, cage-free pullets had limited negative effects at both the high and low-stocking densities tested in this study; there were few to no changes in the numerous bird-based welfare parameters tested.
  • Thumbnail Image
    Effects of a convertible to-and-fro and circle anesthetic system on cardiopulmonary variables in isoflurane anesthetized horses
    Natalini, Claudio Corrêa; Polydoro, Alexandre da Silva D. S.; Cavalcanti, Ruben Lundgren; Branquinho, Luciana Queiroga; Crosignani, Nadia; Serpa, Priscila B. S.; Schallenberger, Rodrigo Gonçalves; Pellin de Molnar, Bruna Favieiro; Carregaro, Adriano; Futema, Fábio (Universidade Federal do Rio Grande do Sul, 2018-03-30)
    Six healthy adult horses two male and four female, mean body weight of 424 + 44.1kg, were anesthetized with xylazine, ketamine/diazepam and isoflurane for 60 minutes using a convertible to-and-fro and circle system. Variables analyzed were arterial blood pH, carbon dioxide partial pressure (PaCO2) and oxygen partial pressure (PaO2), respiratory rate(RR), and blood pressure. The horses were allowed to breath spontaneously, and were positioned in right lateral recumbency. The arterial O2 values were significantly higher during isoflurane anesthesia when compared to the baseline values, and significantly lower after induction with ketamine/diazepam although arterial hypoxemia were not present. The arterial PCO2 values were significantly higher from baseline values during isoflurane anesthesia occurring arterial hypercapnia and mild respiratory acidosis. The arterial pH changes paralleled the changes in PaCO2. Respiratory rate values were significantly lower during isoflurane anesthesia when compared to baseline values. All values remained within accepted range for lateral recumbent spontaneously breathing anesthetized horses. There were no significant differences between the circle and the to-and-fro system, demonstrating that either system is safe to maintain isoflurane anesthesia in adult horses.
  • Thumbnail Image
    Effects of Detomidine Constant Rate Infusion on Blood Glucose and Lactate in Sevoflurane Anesthetized Horses
    Serpa, Priscila B. S.; Natalini, Claudio Corrêa; Cavalcanti, Ruben Lundgren; Nogueira Estrella, Jose Pedro; Pellin de Molnar, Bruna Favieiro; Bezerra, Daniele Pankowski; Pires, Ananda da Rocha D. R.; Fernandes, Viviane Conde (Universidade Federal do Rio Grande do Sul, 2012-01-01)
    Background: The drugs that promote sedation, analgesia, and anesthesia, as inhalatory agents, phenothiazines, benzodiazepines, alpha-2 adrenergic agonists, and opioids, can promote different kinds of side effects. The concept of a balanced anesthesia in equine was developed in order to minimize adverse effects inherent to anesthesia, creating a combination of lower doses of these drugs in comparison with the doses of each one used alone. Alpha-2-adrenoceptor agonists such as xylazine, detomidine, and others, are drugs used for standing sedation, analgesia, and reduction of volatile anesthetic requirement in the equine as well as an agent used to maintenance of arterial blood pressure during anesthesia. Alpha-2 agonists works stimulating receptors of autonomic neurons inducing reduction of heart rate, cardiac output and vascular resistance, hypertension, behavioral changes, and inhibition of insulin secretion. This reduction in insulin levels increases blood glucose concentration in horses due to its lower utilization in insulin-dependent tissues, as muscular and adipose tissues. Muscular tissue is capable to maintain a constant lactate production even in a well oxygenated environment in order to maintain its cellular activity, especially in cases when glucose is not available. To evaluate the effect on blood glucose and lactate, horses were submitted to one hour of detomidine constant rate infusion during sevoflurane inhalatory anesthesia with controlled ventilation, in order to assess blood concentration of glucose and lactate Materials, Methods & Results: Four adult horses were studied. Detomidine 20 μg.kg-1 was used as premedication followed by an association of ketamine and diazepam intravenously as anesthetic induction. After intubation, sevoflurane was vaporized at approximately 2.3 V%. Mechanical ventilation was established. After stabilization, an intravenous continuous rate infusion (CRI) of detomidine 5 μg.kg.h-1 was started. Venous blood samples were collected before premedication, prior to detomidine continuous infusion, 20, 40, and 60 min after beginning of infusion, in order to determination of glucose and lactate serum concentrations. After 60 min of detomidine infusion, the horses were allowed to recovery. There was statistical significant hyperglycemia in the horses under CRI of detomidine. There was no significant increase in blood lactate, despite of the hyperlactatemia in some animals. Discussion: Detomidine CRI of 5 μg.kg.h-1 does increase blood glucose levels over normal values but not to levels that could be toxic to tissues, mainly CNS. With low levels of serum insulin, body tissues, mainly muscular and adipose tissues, are unable to capture this available blood glucose and these cells depend on lactate metabolism. The lactate serum concentrations below normal range observed in studied horses suggest that all lactate produced by the tissues is being utilized in the energetic metabolism. In according to many authors, lactate is produced and utilized for mitochondrias as energetic source even in fully oxygenated tissues, which seems to be what happened in this experiment. The present study helps to understand energetic metabolism in horses under general inhaled anesthesia with detomidine CRI, a selective alpha-2-adrenoceptor agonist. In order to better evaluate energetic metabolism during inhaled anesthesia under detomidine influence, other studies are suggested, as prolonged anesthesia duration to evaluate a longer adrenergic stimulus induced by detomidine. Besides, other investigations with detomidine CRI in horses submitted to surgical procedures could provide different responses in energetic metabolism.
  • Thumbnail Image
    Hemodynamic and Respiratory Effects of Positive End-expiratory Pressure during a Pulmonary Distress Model in Isoflurane Anesthetized Swine
    Cavalcanti, Ruben Lundgren; Serpa, Priscila B. S.; Natalini, Claudio Corrêa (Universidade Federal do Rio Grande do Sul, 2014-10-24)
    Background: Several pulmonary and hemodynamic complications may occur during mechanical ventilation of the lungs. The use of a positive end-expiratory pressure (PEEP) can improve oxygenation and prevent atelectasis, although this method can cause important hemodynamic side effects. Mostly, these hemodynamic effects are due to increased airway pressure that is transferred to the intrapleural space, increasing the intrathoracic pressure, which decreases venous return to the heart. Cardiac output is significantly reduced with high PEEP levels which in turn precludes the improvement effects on blood oxygenation. The aim of this study was to evaluate hemodynamic and respiratory effects of different levels of carbon dioxide insufflations associated with different levels of PEEP under conventional two-lung ventilation in isoflurane anesthetized pigs. Materials, Methods & Results: Twelve juvenile pigs were anesthetized with ketamine and midazolam, and end tidal isoflurane 2.0 V% for maintenance. Animals were submitted to tension pneumothorax through an acute intrathoracic insufflation with carbon dioxide at 0, 5, and 10 mmHg. Mechanical lung ventilation with 100% oxygen was started with zero PEEP then increased to 5 and 10 cmH2O. Ventilatory, respiratory and hemodynamic parameters were measured, as well as blood gases. Tension pneumothorax of 10 mmHg, with both PEEP levels, induced a significant decrease in cardiac index, stroke volume, right ventricular stroke work index, dynamic compliance, arterial pH, arteriovenous oxygen difference, arterial blood pressure, in addition to significance increase in heart rate. Moreover, tension pneumothorax of 5 or 10 mmHg combined with 5 or 10 cmH2O PEEP produced a significant increase in alveolar-arterial oxygen difference, a significant decrease in arterial oxygen content, and arterial partial pressure of O2. Central venous pressure, mean pulmonary arterial pressure, physiologic dead space, and arterial partial pressure of CO2 significantly increased with tension pneumothorax of 5 or 10 cmH2O when 5 or 10 mmHg PEEP was used. Arterial oxygenation improved significantly when 10 cmH2O PEEP was applied to 5 or 10 mmHg tension pneumothorax. Discussion: In this study, a thoracoscopic trocar was used to produce the acute respiratory function impairment. All animals showed the hemodynamic effects of an increased intrapleural pressure (IPP), such as hypotension and decreased SpO2. The major change observed was the increased shunt fraction, due to increased physiologic dead space. The hemodynamic changes observed were mainly due to compression of the large thoracic vessels as well as lung compression. When PEEP was applied without increased IPP, the hemodynamic depressive effects were less important. Levels of ETCO2 in our study did not present a significant increase, demonstrating that recruitment maneuvers are not always effective when there is a concomitant increased IPP. Dead space and V/Q mismatch significantly increased, demonstrating an important respiratory depressant effect. We have demonstrated in this study that while arterial oxygenation and tissue oxygen extraction is improved when high PEEP strategy is used in a swine tension pneumothorax model, the mechanical ventilation of the lungs with low PEEP or high PEEP strategy produced significant depression of the hemodynamic function during tension pneumothorax.
  • Thumbnail Image
    Horse Seminal Plasma proteins (HSP-1 and HSP-2) concentration: a possible marker for poor fertility?
    Garcia, Luisa A. D.; Brito, Enio L. R.; Serpa, Priscila B. S.; Gregory, Joana; Natalini, Claudio Corrêa; Mottos, Rodrigo C.; Jobim, Maria Ines M. (Hippiatrika Verlag, 2014-09-01)
    Seminal plasma (SP) proteins have been assessed in relation to reproductive fertility levels or infertility, in several species of mammals, particularly domestic animals. Horse seminal plasma proteins 1 (HSP-1) and 2 (HSP-2) are the most abundant proteins in equine seminal plasma. The aim of this study was to investigate in adult stallions the concentrations of seminal plasma HSP-1/2 and total protein in the breeding season and non-breeding season and to determine if these concentrations were related with fertility. Seminal plasma was obtained from 42 ejaculates of 11 adult stallions (3-25 yrs). Stallions were allocated into two groups (good and poor fertility) according to pregnancy rates of mares, and to their semen viability data in the first collection day. Seminal plasma HSP-1/2 concentrations (mg/mL) were measured and analyzed by an Ultra High Performance Liquid Cromatography using a UHPLC column. There were significant differences (P<0.05) in total protein and HSP1/2 concentration (mg/mL, meanplusmn;SD) in the ejaculates from good and poor fertility stallions. The HSP1/2 concentration did not show differences in the first and second ejaculates of good fertility stallions in both the non-breeding and breeding season. Seminal plasma of stallions classified as poor fertility showed significant difference (P<0.05) in HSP-1/2 concentration between the first and second ejaculate in both the non-breeding and breeding season. In conclusion, the concentration of the major proteins of stallion seminal plasma HSP1/2 was higher in ejaculates from stallions with poor fertility, is not influenced by the season and could serve as biomarker for poor fertility in stallions.
  • Thumbnail Image
    Incidental diagnosis of a spindle cell type gastrointestinal stromal tumor in a dog with ethylene glycol intoxication
    Serpa, Priscila B. S.; Santos, Andrea P. (Wiley, 2021-11-21)
    A 6-year-old castrated male American Pit Bull Terrier dog was presented for evaluation of acute onset of tonic-clonic seizures, anorexia, and vomiting. On physical examination, neurologic signs, such as generalized proprioceptive ataxia, salivation, circling to the right, and absent patellar reflexes bilaterally, were noted. A complete blood cell count revealed mild hemoconcentration and an inflammatory leukogram, while a chemistry panel showed severe azotemia, marked hypochloremia, and a severe titrational metabolic acidosis, suggesting possible ethylene glycol intoxication. However, an irregularly round, small mass was identified in the large intestine on abdominal ultrasound. Additionally, bilateral hyperechoic renal cortices with medullary rim sign were suggestive of acute nephritis or tubular necrosis. The cytologic evaluation of a fine-needle aspiration biopsy of the abdominal mass revealed a large population of mesenchymal cells, suggesting the presence of neoplasia. Due to the worsening of symptoms, the dog was humanely euthanized. Necropsy confirmed ethylene glycol intoxication, and the incidental finding of a neoplastic intestinal mass was diagnosed as spindle cell sarcoma. Immunohistochemical staining showed strong, diffuse positivity for CD117, smooth muscle actin, and S-100, indicating the final diagnosis of a spindle cell type gastrointestinal stromal tumor (GIST). This report briefly discusses the classifications of nonlymphoid, nonangiogenic intestinal mesenchymal tumors, characteristics of GISTs, and the importance of the immunohistochemical classification of mesenchymal tumors of the gastrointestinal tract.
  • Thumbnail Image
    Molecular detection of equid herpesvirus in bronchoalveolar lavage fluid from asymptomatic horses in Southern Brazil
    Finger, Mariane Angelica; Biava, Janaina Socolovski; Dornbusch, Peterson Triches; Perotta, Joao Henrique; Ullmann, Leila Sabrina; Serpa, Priscila B. S.; Kmetiuk, Louise Bach; dos Santos, Andrea Pires; Biondo, Alexander Welker; Leutenegger, Christian; de Barros Filho, Ivan Roque (Veterinary World, 2022-11)
    Background and Aim: Molecular approaches to diagnose respiratory viruses have provided an opportunity for early and subclinical pathogen detection, particularly in samples from the upper respiratory tract. This study aimed to investigate the presence of herpesviruses, particularly equid herpesvirus (EHV)-2 and EHV-5, in samples from the lower respiratory tract of healthy racehorses from Southern Brazil. Materials and Methods: Samples from the lower respiratory tract (i.e., bronchoalveolar lavage fluid [BALF]) were assessed by video endoscopy, cytological evaluation of BALF, and tracheal aspirates (TA), along with quantitative polymerase chain reaction (qPCR), to detect equine herpesvirus infection in the lower respiratory tract samples and compare corresponding cytological and endoscopic findings. Results: At least one abnormality per horse during endoscopy examination was observed, including, but not limited to, mucous secretion in the airways and pharyngeal lymphoid hyperplasia. The presence of EHV-2 and/or EHV-5 was detected by qPCR in 3/10 animals. One horse was positive for EHV-2 alone, one for EHV-5 alone, and one for both. Conclusion: To the authors' knowledge, this is the first molecular detection of EHV-2 and EHV-5 in Brazilian thoroughbred horses. These findings may provide new insights into the epidemiology of EHV-2 and EHV-5 in Brazilian horses, evidencing the importance of the molecular investigation, early detection, and prevention of respiratory diseases.
  • Thumbnail Image
    Use of Calcium Chloride as an Adjuvant in Cardiopulmonary Cerebral Resuscitation (CPCR) in Dogs
    Natalini, Claudio Corrêa; Nogueira Estrella, Jose Pedro; Polydoro, Alexandre da Silva D. S.; Futema, Fábio; Serpa, Priscila B. S. (Universidade Federal do Rio Grande do Sul, 2011-01-01)
    Background: Treatment of cardiopulmonary arrest has been a source of discussion in both medicine as in veterinary with an emphasis on the use of solutions with calcium because of its importance as an ion essential for heart's functionality. Only a few studies have showed the use of Ca 2+ in CPCR. Based on this, the present study aimed to evaluate the use of calcium chloride as an adjuvant therapy in CPCR in dogs. Materials, Methods & Results: Eighteen cases of CPCR from the hospital routine of HCV-UFRGS were studied. Cases were selected from those in which occurred a cardiopulmonary arrest with reversal to a ventricular asystole in dogs. These animals were divided into two groups. In nine animals from the group called EPI, epinephrine was administered intravenously at a dose of 0.1 mg.kg -1 or by pulmonary route in a dose of 0.2 mg.kg -1. In the remaining nine animals, named EPIC group, the protocol was similar to the previous group, with the addition of the administration of calcium chloride 10% immediately after administration of epinephrine. In EPI group, the overall rate of success was 55.6%, and three of the cases treated showed reversion to normal sinus rhythm asystole. In the remaining six cases, four progressed to nonresponsive transient ventricular tachycardia (VT) and death, and two progressed to junctional rhythm. In the EPIC group, the overall rate of success was 22.2%. Four animals had VF from an asystole, in which in two of them were reversed by electric defibrillation, and in two of them the reversal was not obtained. In the other five treated animals, a ventricular tachycardia was developed followed by an irreversible cardiac arrest. Discussion: The incidence and prevalence of cardiac arrest diagnosed in animals in both hospitals and outpatients are still scarce data. However when it comes to patients under anesthesia, the success rate of CPCR are low compared to medicine. Calcium ion is indispensable in order to generate activation of the cardiac myofilaments to produce contraction of the heart. Cardiopulmonary arrest leads to a series of physiological changes that decrease the ability of the myocardium to maintain their automaticity and, in turn, generate a cardiac pacemaker, as well as its contractility. Several studies show that such these changes could be because of a severe hypocalcemia, found in both humans and dogs. Despite of the recent consensus against its use, calcium chloride in CPCR can increase the intracellular levels of this ion, which can cause inhibition of cellular respiration and energy production in mitochondrias, triggering an enzymatic proteolytic reaction, leading to cell death. However there is a clear exception in cases where the patient is in a framework of hypocalcemia. The EPI group has reached better rates of success; however, in the EPIC group was observed a reversal of asystole to VF, a fact that did not occur in group EPI. The treatment for VF is electric defibrillation, with a better prognosis when compared to asystole. Although the EPI group has obtained the best result and epinephrine rather is the best treatment of choice to CPCR, the EPIC group demonstrated that the use of calcium chloride may be an alternative to try to transform a VF in an asystole, with the possibility of using electric defibrillator in patients unresponsive to epinephrine alone.
  • Thumbnail Image
    What is your diagnosis? Abdominal mass in a rat
    Serpa, Priscila B. S.; Corriveau, Lorraine A.; Santos, Andrea P. (Wiley, 2022-01-01)
    A pet rat (Rattus novergicus) was diagnosed with sarcoma after cytologic and histologic evaluation of a subcutaneous, ventrally-located abdominal mass. Immunohistochemistry revealed neoplastic cells positive for Iba-1 and CD204, indicating a final diagnosis of histiocytic sarcoma. The tumor was aggressive and spread in a few weeks, leading to humane euthanasia.