Minimal and normal-flow general anesthesia in patients undergoing surgery in prone position: impact on hemodynamics and regional cerebral oxygenation

Purpose: In this study, the aim to assess the combined effects of prone-positioning (PP) and minimal-flow (MF) general anesthesia on regional cerebral oxygenation (RCO) and systemic hemodynamics. Methods: This is a randomized prospective study aiming to evaluate changes in cerebral oxygenation and hemodynamic parameters in MF systemic anesthesia in patients undergoing surgery in PP. Patients were randomized to MF or normal-flow (NF) anesthesia. In the operating room, pulse rate, mean arterial pressure (MAP), peripheral hemoglobin oxygen saturation (spO2), and right- and left-side RCO (assessed by nearinfrared spectroscopy, NIRS) were measured perioperatively. Results: Overall, 46 patients were included (24 in the MF group and 22 in the NF group). The amount of anesthetic gas consumption was significantly lower in the low-flow (LF) group. In both groups, the mean pulse rate showed a decrease after PP. Before induction, RCO was significantly higher both at the right- and left-sides in the LF group compared to the NF group. This difference continued throughout the operation on the left-side and disappeared 10 min after intubation on the right-side. On the left side, mean RCO decreased after PP in both groups. Conclusion: MF anesthesia in PP did not reduce cerebral oxygenation compared to NF and was safe in terms of systemic hemodynamics and cerebral oxygenation.

Protocolo anestésico em guaxinim submetido à colocefalectomia / Anesthesic protocol in a raccoon submitted to colocephalectomy

Em guaxinins, comumente se observa a presença de osteoartrites acometendo a articulação coxofemoral. Em carnívoros domésticos, o tratamento pode ser conservativo ou cirúrgico e, dentre as técnicas cirúrgicas, cita-se a colocefalectomia. Por ser um procedimento que provoca dor moderada a severa, um protocolo de anestesia balanceada se faz necessário, podendo associar a técnicas de bloqueio locorregional, como a epidural. Protocolos descritos para a espécie são limitados, porém comumente empregados para contenções químicas, avaliações físicas e exames de imagem. Portanto, o objetivo deste trabalho é relatar a o protocolo anestésico realizado em guaxinim (Procyon cancrivorus) submetido à colocefalectomia. Foram utilizados dexmedetomidina (5µg/kg), cetamina (5mg/kg) e diazepam (0,3mg/kg) por via intramuscular como medicação pré-anestésica, indução com propofol e manutenção por anestesia inalatória com isoflurano. Para execução da anestesia epidural, realizou-se uma abordagem na região lombossacral, sendo administrados bupivacaína (1mg/kg) e morfina (0,1mg/kg). Não houve intercorrências e os parâmetros fisiológicos mantiveram-se estáveis. Descartou-se a necessidade de resgate analgésico e a recuperação anestésica foi rápida. Dessa forma, conclui-se que o manejo anestésico proposto promoveu estabilidade hemodinâmica e recuperação satisfatórias para a espécie.

In raccoons, the presence of osteoarthritis affecting the hip joint is commonly observed. In domestic carnivores, the treatment can be conservative or surgical and, among the surgical techniques, colocephalectomy is mentioned. Since it is a procedure that causes moderate to severe pain, a balanced anesthesia protocol is necessary, which can be associated with locoregional block techniques such as the epidural. Protocols described for the species are limited, being commonly used for chemical restraints, physical assessments, and imaging exams. Therefore, this work aims to report the anesthetic protocol performed on a raccoon (Procyon cancrivorus) submitted to colocephalectomy. Dexmedetomidine (5µg/kg), ketamine (5mg/kg), and diazepam (0.3mg/kg) were used intramuscularly as pre-anesthetic medication, in addition to induction with propofol, and the maintenance by inhalational anesthesia with isoflurane. For epidural anesthesia, an approach was performed in the lumbosacral region, with the administration of bupivacaine (1mg/kg) and morphine (0.1mg/kg). There were no complications and the physiological parameters remained stable. The need for analgesic rescue was ruled out and the anesthetic recovery was fast. Thus, it is concluded that the proposed anesthetic management promoted hemodynamic stability and a satisfactory recovery for the species.

Anestesia para orquiectomia em equino criptorquídico: relato de caso / Anesthesia for orchiectomy in a cryptorchid horse: case report

O criptorquidismo é uma das afecções testiculares mais comuns nos equídeos, caracterizada pela não descida de um ou dos dois testículos para a bolsa escrotal. O tratamento para esta afecção se resume em orquiectomia bilateral, necessitando de um procedimento anestésico. No presente trabalho, para a escolha do protocolo anestésico, foi levado em consideração o tempo cirúrgico, o procedimento cirúrgico, o decúbito e a espécie do animal. Com a evolução da anestesiologia veterinária, novas técnicas têm sido utilizadas, como o uso da anestesia parcialmente intravenosa (Piva) para buscar maior estabilidade hemodinâmica, melhores planos anestésicos, estabilidade transanestésica, analgesia e recuperação mais rápida.(AU)

Cryptorchidism is one of the most common testicular disorders in horses, characterized by the failure of one or both testicles to descend into the scrotum. The treatment for this affection is bilateral orchiectomy, requiring an anesthetic procedure. In the present study, for the choice of the anesthetic protocol the surgical time, the surgical procedure, the decubitus and the species of the animal were taken into consideration. With the evolution of veterinary anesthesiology, new techniques have been used, such as the use of partial intravenous anesthesia (Piva) to seek greater hemodynamic stability, better anesthetic plans, trans-anesthetic stability, analgesia, and faster recovery.(AU)

B-mode and Doppler ultrasound of bitches' kidneys with mammary neoplasia submitted to adjuvant chemotherapy / Ultrassonografia modo-B e Doppler dos rins de cadelas com neoplasias mamárias submetidas à quimioterapia adjuvante

Mammary neoplasia represents the most frequently diagnosed type of neoplasia in bitches. Although surgical removal is the procedure of choice for therapeutic management, chemotherapy protocols appear as important allies and adjuvants. Despite the great advances that have occurred in the field of cancer therapy, the systemic repercussions of these drugs still impose important limitations on their use. In this sense, the development of increasingly targeted therapeutic protocols and preventive monitoring of patients represent important strategies to avoid possible complications - among them, Acute Kidney Injury (AKI). Routinely, ultrasound evaluation is used to identify morphological or metastatic variations in abdominal cavity organs. Acting complementary to the B-mode evaluation, Doppler mapping proves to be efficient in recognizing alterations in vascular hemodynamics. Therefore, the objective of the present study was to evaluate the use of B-mode and Doppler ultrasound to identify renal morphological and hemodynamic alterations in bitches with mammary neoplasia submitted to adjuvant chemotherapy protocols that associate gemcitabine with carboplatin. Thirteen bitches were included, without distinction of breed and between seven and 13 years of age. The animals were evaluated ultrasonographically at two different times during three consecutive chemotherapy cycles: before (T0) and one and a half hours after each cycle (T1), for 42 days. No morphological changes were observed in B-mode throughout the chemotherapy protocol. However, the Doppler velocimetry indices demonstrated statistical differences before (T0) and after (T1) the administration of the drugs. It was concluded that Doppler ultrasound could be used as a complementary method for monitoring the renal response of patients exposed to nephrotoxic drugs and potentially causing renal injury.

As neoplasias mamárias representam o tipo de neoplasma mais frequentemente diagnosticado em fêmeas da espécie canina. Embora a remoção cirúrgica seja o procedimento de eleição para a conduta terapêutica, os protocolos quimioterápicos aparecem como importantes aliados e adjuvantes. Apesar dos grandes avanços ocorridos na área da terapia oncológica, as repercussões sistêmicas destes fármacos ainda impõem importantes limitações ao seu uso. Neste sentido, o desenvolvimento de protocolos terapêuticos cada vez mais direcionados e o monitoramento preventivo dos pacientes representam estratégias importantes para evitar possíveis complicações - dentre elas, a injúria renal aguda (IRA). Rotineiramente, a avaliação ultrassonográfica é utilizada para identificação de variações morfológicas ou metastáticas em órgãos da cavidade abdominal. Atuando de forma complementar à avaliação em modo-B, o mapeamento Doppler mostra-se eficiente no reconhecimento de alterações na hemodinâmica vascular. Portanto, o objetivo do presente estudo foi avaliar a utilização da ultrassonografia modo-B e Doppler como método para identificação de alterações morfológicas e hemodinâmicas renais em cadelas com neoplasias mamárias submetidas a protocolos quimioterápicos adjuvantes que associam a gencitabina à carboplatina. Foram incluídas 13 fêmeas caninas, sem distinção quanto a raça e com idades entre sete e 13 anos. Os animais foram avaliados ultrassonograficamente em dois momentos distintos durante três ciclos quimioterápicos consecutivos: antes (T0) e uma hora e meia após a realização de cada ciclo (T1), totalizando 42 dias. Não foram observadas alterações morfológicas em modo-B ao longo do protocolo quimioterápico. Entretanto, os índices dopplervelocimétricos demonstraram diferenças estatísticas antes (T0) e após (T1) a administração dos fármacos. Concluiu-se que a ultrassonografia Doppler pode ser utilizada como método complementar para o monitoramento da resposta renal de pacientes expostos a fármacos nefrotóxicos e potencialmente causadores de injúrias renais.

Presumed normal hemodynamic values of the arteries in the final third period of gestation in bitches

Background: Doppler ultrasonography enables the investigation of vascular blood flow indexes in gestational assessment,being able to detect vascular resistances that can affect fetal and maternal circulation, such as cases of placental insufficiency, associated with fetal cerebral oxygenation deficit and fetal distress. The study aims to assume hemodynamicallynormal values in the final third of gestation in bitches, of the umbilical, uteroplacental, middle cerebral and internal carotidarteries, correlating the obtained Doppler velocimetric indexes, for the assessment of the feto-placental circulation, andprediction of fetal viability indexes, fetal centralization and probable date of delivery.Materials, Methods & Results: Thirty healthy bitches were examined in the final third of gestation (40-60 days). Thesewere evaluated by Doppler ultrasonography at 2 times (T): T1: between 40-50 days; T2: between 51-60 of gestation.At each time point, the peak systolic velocities (PSV) and end-diastolic velocities (EDV) used to obtain the pulsatility(IP) and resistivity (IR) indexes of the umbilical, uteroplacental, middle cerebral and internal carotid arteries of fetuseswere evaluated. Also, the systole/diastole (S/D) ratio of these vessels was evaluated. The data obtained were subjected toanalysis of variance and Tukey test, using a P value equal to 5%. A significant difference was observed between velocitiesand Doppler velocimetric indexes between the 2 phases of the gestational final third in all studied vessels. There was anincrease in the values of PSV and EDV and a decrease in the indexes, as the probable date of delivery approached. Theanalysis of the umbilical cord IR showed an increase from P1 to P2 (P < 0.05), while the IP decreased at the same time.For all studied variables there was a statistically significant difference (P < 0.05). In the uteroplacental...(AU)

Presumed normal hemodynamic values of the arteries in the final third period of gestation in bitches

Background: Doppler ultrasonography enables the investigation of vascular blood flow indexes in gestational assessment,being able to detect vascular resistances that can affect fetal and maternal circulation, such as cases of placental insufficiency, associated with fetal cerebral oxygenation deficit and fetal distress. The study aims to assume hemodynamicallynormal values in the final third of gestation in bitches, of the umbilical, uteroplacental, middle cerebral and internal carotidarteries, correlating the obtained Doppler velocimetric indexes, for the assessment of the feto-placental circulation, andprediction of fetal viability indexes, fetal centralization and probable date of delivery.Materials, Methods & Results: Thirty healthy bitches were examined in the final third of gestation (40-60 days). Thesewere evaluated by Doppler ultrasonography at 2 times (T): T1: between 40-50 days; T2: between 51-60 of gestation.At each time point, the peak systolic velocities (PSV) and end-diastolic velocities (EDV) used to obtain the pulsatility(IP) and resistivity (IR) indexes of the umbilical, uteroplacental, middle cerebral and internal carotid arteries of fetuseswere evaluated. Also, the systole/diastole (S/D) ratio of these vessels was evaluated. The data obtained were subjected toanalysis of variance and Tukey test, using a P value equal to 5%. A significant difference was observed between velocitiesand Doppler velocimetric indexes between the 2 phases of the gestational final third in all studied vessels. There was anincrease in the values of PSV and EDV and a decrease in the indexes, as the probable date of delivery approached. Theanalysis of the umbilical cord IR showed an increase from P1 to P2 (P < 0.05), while the IP decreased at the same time.For all studied variables there was a statistically significant difference (P < 0.05). In the uteroplacental...

Fetal distress during the last third of pregnancy in bitches - evaluation by Doppler ultrasound imaging

Background: Diagnostic ultrasound has revolutionized obstetric practice. Doppler techniques provided in vivo studies of the fetus-placental and uterus-placental circulations, in an increasingly precise manner. The assessment of fetal well-being is essential in obstetric practice, however, in veterinary medicine, there is a deficit of ultrasound parameters related to fetal distress. The main of this research was to determine the hemodynamic characteristics and behavior, through Doppler ultrasonography, of maternal-fetal vessels during the final third of gestation in bitches with fetuses under stress, as well as correlating them with each other and with fetal distress. Materials, Methods & Results: An observational, prospective study was carried out, in which 30 healthy bitches were examined, during the last third of pregnancy, with fetuses under fetal distress. Fetuses were evaluated in 2 stages: (1st): 50-54 days and (2nd): 55-60 days of gestation. All fetuses were calmly assessed, one by one, and fetal heart rate (FHR) was measured 5 times, for at least 3 min, to identify and confirm fetal distress. At least 3 fetuses were evaluated in each bitch and each measurement was performed in triplicate, setting a hemodynamic mean for each value evaluated. The flow pattern in the middle cerebral artery (MCA), internal carotid artery (ICA) and umbilical artery (UA) was evaluated. The analyzed vessel was initially visualized in B mode, followed by evaluation by color and spectral Doppler. The variables observed were: peak systolic velocity (PSV), end diastolic velocity (EDV) and the resistivity (RI) and pulsatility (PI) index, as well as the systole/diastole ratio (S/D). The analysis of RI and PI of the umbilical artery showed a statistically significant difference between the mean values found for the times studied, increasing from time 1 to time 2. For middle cerebral and internal carotid arteries, PI, RI and the relationship systole/diastole (S/D), showed a statistically significant difference between the mean values found for the times studied, decreasing from time 1 to time 2. Discussion: Fetal heart rate (HR) findings are considered normal above 200 beats per minute (bpm), only if preceded by acceleration and deceleration. This fact confirms the presence of fetal stress, by this parameter, for the fetuses in the present study. Corroborating the picture of fetal distress, another study concluded that HR tends to increase up to 20 days before delivery, a fact that did not occur in the study in question, where animals in the same gestational period were evaluated. Recent research has concluded that an elevated umbilical artery PI at 28 weeks of gestation, in the absence of fetal growth restriction or prematurity, is associated with some adverse cognitive findings in 12-year-olds children. In the present study, a progressive increase in this index was observed throughout the final third of pregnancy. Although the pups were not monitored after birth, this data serves as a warning for veterinarians, and can be useful in the assessment and diagnosis of possible postnatal nervous alterations. Like what was found in the present study, a study reported that from the 4th week to birth, the PSV of the umbilical artery (UA) increased almost linearly, with high significance. For the middle cerebral arteries, the PI showed a statistically significant difference between the mean values found for the times studied, however, decreasing throughout the final third of pregnancy.

Bezold-Jarisch reflex induced by dopamine during isoflurane anesthesia in small dogs

Background: Unlike other major reflexes contributing to hemodynamic homeostasis, the Bezold-Jarisch reflex (BJR)paradoxically decreases heart rate (HR) and mean arterial pressure (MAP) despite hypotension. In the veterinary field,there are few reported cases of BJR induced by dopamine, which is often used to manage hypotension. Herein, 2 casesinvolving small dogs exhibiting BJR due to dopamine infusion during general anesthesia are described.Cases: Case 1: A 7-year-old, 7 kg, mongrel was referred for external skeletal fixator removal. The patient was premedicatedwith 0.3 mg/kg midazolam and 0.2 mg/kg butorphanol intravenously (IV). General anesthesia was induced with 6 mg/kgpropofol and maintained with 1.6% isoflurane in oxygen. The patient was given 5 mL/kg/h of Hartmann’s solution IV. Therespiratory rate (RR) was set to 9 breaths/min with a ventilator. The HR and MAP values were initially 120 bpm and 76mmHg and gradually decreased to 70 bpm and 40 mmHg, respectively. The end-tidal CO2 partial pressure (ETCO2) was 39mmHg, and the patient was administered 2.5 μg/kg glycopyrrolate IV. Then, 5 μg/kg/min dopamine was administered IVsince the MAP did not improve. The HR, MAP, and ETCO2 increased to 113 bpm, 72 mmHg, and 47 mmHg, respectively.Subsequently, HR and MAP dramatically decreased to 50 bpm and 43 mmHg, respectively. A second-degree atrioventricularblock was detected, prompting dopamine infusion discontinuation, and 2.5 μg/kg glycopyrrolate was again administeredIV. Within 5 min, HR and MAP values normalized, and postoperative patient recovery was typical. Case 2: A 2-year-old,8.6 kg, mongrel underwent surgery to correct a medial luxating patella of the right leg. The patient was premedicated with0.3 mg/kg midazolam and 0.2 mg/kg butorphanol IV. Anesthesia was induced with 4 mg/kg propofol IV and maintained...

Bezold-Jarisch reflex induced by dopamine during isoflurane anesthesia in small dogs

Background: Unlike other major reflexes contributing to hemodynamic homeostasis, the Bezold-Jarisch reflex (BJR)paradoxically decreases heart rate (HR) and mean arterial pressure (MAP) despite hypotension. In the veterinary field,there are few reported cases of BJR induced by dopamine, which is often used to manage hypotension. Herein, 2 casesinvolving small dogs exhibiting BJR due to dopamine infusion during general anesthesia are described.Cases: Case 1: A 7-year-old, 7 kg, mongrel was referred for external skeletal fixator removal. The patient was premedicatedwith 0.3 mg/kg midazolam and 0.2 mg/kg butorphanol intravenously (IV). General anesthesia was induced with 6 mg/kgpropofol and maintained with 1.6% isoflurane in oxygen. The patient was given 5 mL/kg/h of Hartmanns solution IV. Therespiratory rate (RR) was set to 9 breaths/min with a ventilator. The HR and MAP values were initially 120 bpm and 76mmHg and gradually decreased to 70 bpm and 40 mmHg, respectively. The end-tidal CO2 partial pressure (ETCO2) was 39mmHg, and the patient was administered 2.5 μg/kg glycopyrrolate IV. Then, 5 μg/kg/min dopamine was administered IVsince the MAP did not improve. The HR, MAP, and ETCO2 increased to 113 bpm, 72 mmHg, and 47 mmHg, respectively.Subsequently, HR and MAP dramatically decreased to 50 bpm and 43 mmHg, respectively. A second-degree atrioventricularblock was detected, prompting dopamine infusion discontinuation, and 2.5 μg/kg glycopyrrolate was again administeredIV. Within 5 min, HR and MAP values normalized, and postoperative patient recovery was typical. Case 2: A 2-year-old,8.6 kg, mongrel underwent surgery to correct a medial luxating patella of the right leg. The patient was premedicated with0.3 mg/kg midazolam and 0.2 mg/kg butorphanol IV. Anesthesia was induced with 4 mg/kg propofol IV and maintained...(AU)

Níveis de progesterona e os parâmetros reprodutivos no período periovulatório de vacas Nelore submetidas ao protocolo de IATF / Progesterone levels and reproductive parameters in the periovulatory period of Nellore cows under FTAI protocol

Background: Fixed Time Artificial Insemination (FTAI) has achieved a significant evolution in the last 18 years, however, despite the progress achieved by modern FTAI programs, the conception rates obtained are still low. Therefore, this study aimed to evaluate the interrelation between progesterone levels in the periovulatory period and reproductive parameters of Nellore cows submitted to an FTAI protocol. Materials, Methods & Results: On a random day, called day 0 (D0), 57 cows received a P4 device associated with the intramuscular (IM) application of 2.0 mg of estradiol benzoate. On D9, the P4 devices were removed and then were administered 500 µg of cloprostenol sodium IM; 0.6 mg of estradiol cypionate IM and 300 IUI of Equine Chorionic Gonadotrophin IM. Blood samples were collected for the determination of serum P4 concentrations on D9 and D11 of the protocol. The evaluations of follicular diameter (DFOL), follicular wall area (AFOL) and the vascularization area of the follicle wall (VFOL) were carried out on D11 using B-mode ultrasonography examination and colour Doppler, and then the artificial inseminations were performed. The evaluation of the corpus luteum diameter (CLD), of the total corpus luteum area (CLA), of the area of corpus luteum vascularization (CLV) and blood sampling for determination of postovulatory P4 levels (Post-P4) were performed on D24. For the analysis of the P4 concentration the chemiluminescence method was used, with a sensitivity of 0.1 ng/mL. According to the P4 concentrations on D11, cows were divided into 2 groups, LOW LEVELS OF P4 and HIGH LEVELS OF P4. The diagnosis of pregnancy was performed using transrectal ultrasonography on D45, at this point the cows were divided into 2 groups, PREGNANT and NON-PREGNANT. The correlation between DFOL and P4 dosage on D11 was moderate, negative and significant and between the AFOL and the serum P4 levels on D9, was moderate, negative and significant. As for the other correlations between follicular and luteal parameters and serum P4 levels, these were low to moderate, negative and not significant. Cows in the LOW LEVELS OF P4 group had significantly larger diameter and follicular areas than the cows in the HIGH LEVELS OF P4 group, the other follicular and luteal parameters showed no statistical difference. Of the total 57 cows that were inseminated, 30 cows became pregnant. Cows in the PREGNANT group had serum P4 levels on D9 equivalent to that obtained by the NON-PREGNANT group. However, at D11 the cows that became pregnant presented significantly lower serum P4 levels than cows that did not become pregnant. Discussion: The results of the interrelation between follicular parameters and P4 levels obtained in the present study, pointed out that the lower the levels of P4, the higher the follicular parameters, corroborating with other authors. Thus, larger preovulatory follicles provided high ovulation rates. Periovulatory serum P4 levels did not significantly affect the morphofunctional parameters of the CL. Such findings may be justified by high periovulatory P4 levels resulting from less efficient luteolysis, exert a negative effect on the results of FTAI protocols, because progesterone inhibits the release of LH pulses. It is concluded that lower periovulatory P4 levels established a favourable condition for follicular development and fertility, however, morphofunctional parameters of the corpus luteum were not affected.

Effects of dexmedetomidine on hemodynamic, oxygenation, microcirculation, and inflammatory markers in a porcine model of sepsis

Purpose: To determine whether dexmedetomidine aggravates hemodynamic, metabolic variables, inflammatory markers, and microcirculation in experimental septic shock. Methods: Twenty-four pigs randomized into: Sham group (n = 8), received saline; Shock group (n = 8), received an intravenous infusion of Escherichia coli O55 (3 × 109 cells/mL, 0.75 mL/kg, 1 hour); Dex-Shock group (n = 8), received bacteria and intravenous dexmedetomidine (bolus 0.5 mcg/kg followed by 0.7 mcg/kg/h). Fluid therapy and/ornorepinephrine were administered to maintain a mean arterial pressure > 65 mmHg. Hemodynamic, metabolic, oxygenation, inflammatory markers, and microcirculation were assessed at baseline, at the end of bacterial infusion, and after 60, 120, 180, and 240 minutes. Results: Compared to Shock group, Dex-Shock group presented a significantly increased oxygen extraction ratio at T180 (23.1 ± 9.7 vs. 32.5 ± 9.2%, P = 0.0220), decreased central venous pressure at T120 (11.6 ± 1 vs. 9.61 ± 1.2 mmHg, P = 0.0214), mixed-venous oxygen saturation at T180 (72.9 ± 9.6 vs. 63.5 ± 9.2%, P = 0.026), and increased plasma lactate (3.7 ± 0.5 vs. 5.5 ± 1 mmol/L, P = 0.003). Despite the Dex-Shock group having a better sublingual vessel density at T240 (12.5 ± 0.4 vs. 14.4 ± 0.3 mL/m2; P = 0.0003), sublingual blood flow was not different from that in the Shock group (2.4 ± 0.2 vs. 2.4 ± 0.1 mL/kg, P = 0.4418). Conclusions: Dexmedetomidine did not worsen the hemodynamic, metabolic, inflammatory, or sublingual blood flow disorders resulting from septic shock. Despite inducing a better sublingual vessel density, dexmedetomidine initially and transitorily increased the mismatch between oxygen supply and demand.

Conventional vs. advanced echocardiographic parameters for predicting fluid responsiveness in healthy dogs

Background: Volume replacement is considered an essential component in the treatment of critically ill patients, but excess f luid administration can be as harmful as the lack of fluid therapy. Therefore, the volume replacement is only beneficial in patients deemed to be fluid responsive, that is, when the individual has an increase in their stroke volume after administration of a volume challenge. This study aim to assess whether conventional and advanced echocardiographic parameters for assessing left ventricular systolic function are able to predict fluid responsiveness in healthy spontaneously breathing dogs. The hypothesis was that some of these parameters would differ between responsive and non-responsive animals and could be used as a complementary measure for assessment of fluid responsiveness. Materials, Methods & Results: A prospective study was carried out in which 22 client-owned healthy dogs over 1 year of age that presented to the Veterinary Medical Teaching Hospital for elective neutering procedure were included. All dogs underwent conventional and advanced echocardiographic examination to obtain the left ventricular internal diameter in diastole normalized (LVIDDn), left ventricular internal diameter in systole normalized (LVIDSn), ejection fraction (EF) and shortening fraction (SF) according to the Teischholz methodology, global longitudinal strain (GLS) and tissue motion annular displacement (TMAD). There parameters were evaluated before and after administration of a volume challenge with 10 mL/kg lactate ringer intravenously for 20 min. Based on the variation in aortic velocity integral time, 31.82% of dogs were considered responsive and 68.18% were non-responsive to the volume challenge. For advanced echocardiography, TMAD indexed by body weight (mm/kg) > 0.89 (P = 0.004) and body surface area (mm/m2) >18.9 (P = 0.004) after volume challenge had the best area...

Efeitos cardiorrespiratórios da dexmedetomidina isolada e associada à morfina na medicação pré-anestésica de cadelas submetidas à ovariohisterectomia eletiva / Cardiorespiratory effects of dexmedetomidine alone and associated to morphine as premedicants in healthy bitches undergoing ovariohisterectomy / Efectos cardiorespiratorios de la dexmedetomidina aislada y asociada con morfina sobre medicamentos pre-anestésicos de perras sometidas a ovariohisterectomía electiva

Objetivou-se avaliar os efeitos cardiorrespiratórios da dexmedetomidina isolada e associada à morfina em pacientes submetidas à anestesia geral inalatória com isoflurano e submetidas à ovariohisterectomia eletiva. Vinte cadelas saudáveis foram selecionadas a partir de exames físico e laboratoriais. Os animais foram distribuídos aleatoriamente em dois grupos: dexmedetomidina (10 µg/Kg) (GD) e dexmedetomidina (10 µg/Kg) associado com morfina 0,3 mg/Kg (GDM), administrados pela via intramuscular (IM). Ato contínuo, o paciente foi induzido com propofol (à efeito) e mantido com isoflurano diluído em oxigênio 100% e administrado através de vaporizador calibrado. Foram aferidos os parâmetros fisiológicos: frequências cardíaca (FC) e respiratória (f), temperatura corporal (T°C), pressões arteriais sistólica (PAS), diastólica (PAD) e média (PAM), saturação de oxigênio na hemoglobina (SpO2), pressão parcial de gás carbônico no final da expiração (ETCO2) e isoflurano expirado (ETISO). A hemogasometria arterial foi utilizada para a análise do potencial hidrogeniônico (pH), bicarbonato (HCO3-) e pressão parcial de dióxido de carbono (PaCO2). O procedimento cirúrgico teve duração máxima de 45 minutos. Os parâmetros demonstraram diferença estatística entre os tempos e grupos avaliados, de acordo com os testes de Tukey e Bonferroni (p<0,05). Observou-se bradicardia 30 minutos após a aplicação da medicação pré-anestésica e acidemia no período trans-anestésico. Apesar disto, tanto a dexmedetomidina isolada quanto associada, conferiram estabilidade hemodinâmica e respiratória, apesar da bradicardia e acidemia observada.(AU)

This study aimed to evaluate the cardiorespiratory effects of dexmedetomidine alone and associated with morphine. Twenty healthy dogs were selected from physical and laboratory exams. The animals were randomly distributed into two groups: 10 µg/Kg dexmedetomidine (DG) and 10 µg/Kg dexmedetomidine group associated with 0.3 mg/Kg morphine (GDM), administered intramuscularly (IM). The patients were induced with propofol (to effect) and maintained with isoflurane diluted in 100% oxygen and administered through a calibrated vaporizer. Physiological parameters were measured: heart rate (HR), respiratory rate (f), body temperature (T°C), systolic arterial pressure (SAP), diastolic arterial pressure (DAP) and mean arterial pressure (MAP), oxygen saturation of hemoglobin (SpO2), end-tidal carbon dioxide partial pressure (ETCO2) and end-tidal isoflurane concentration (ETISO). Arterial blood gas analysis was used to analyze hydrogen potential (pH), bicarbonate (HCO3-) and partial pressure of carbon dioxide (PaCO2). The surgical procedure lasted up to 45 minutes. The parameters showed a statistical difference between the times and groups evaluated, according to the Tukey and Bonferroni tests (p<0.05). Bradycardia was observed 30 minutes after the application of pre-anesthesic medication and acidemia in the trans-anesthetic period. Despite this, both dexmedetomidine alone and associated, provided good hemodynamic and respiratory stability, despite the bradycardia and acidemia observed.(AU)

Este estudio tuvo como objetivo evaluar los efectos cardiorrespiratorios de la dexmedetomidina sola y asociada con la morfina en pacientes sometidas a anestesia general por inhalación con isoflurano y sometidas a ovariohisterectomía electiva. Se seleccionaron veinte perras sanas a partir de exámenes físicos y de laboratorio. Los animales se dividieron aleatoriamente en dos grupos: dexmedetomidina (10 µg/kg) (GD) y dexmedetomidina (10 µg/kg) asociada con 0,3 mg/kg de morfina (GDM), administrada por vía intramuscular (IM). Posteriormente, el paciente fue inducido con propofol (en efecto) y mantenido con isoflurano diluido en oxígeno al 100% y administrado mediante de un vaporizador calibrado. Se midieron parámetros fisiológicos: frecuencia cardíaca (FC) y respiratoria (f), temperatura corporal (T°C), presión arterial sistólica (PAS), diastólica (PAD) y media (PAM), saturación de oxígeno de hemoglobina (SpO2), presión parcial de carbono dióxido al final de la expiración (ETCO2) e isoflurano expirado (ETISO). Se utilizó gasometría arterial para analizar el potencial de hidrógeno (pH), el bicarbonato (HCO3-) y la presión parcial de dióxido de carbono (PaCO2). El procedimiento quirúrgico tuvo una duración máxima de 45 minutos. Los parámetros mostraron diferencia estadística entre los tiempos y grupos evaluados, según las pruebas de Tukey y Bonferroni (p <0.05). Se observó bradicardia 30 minutos después de la aplicación de medicación preanestésica y acidemia en el período transnestésico. A pesar de esto, tanto la dexmedetomidina aislada como la asociada proporcionaron estabilidad hemodinámica y respiratoria, a pesar de la bradicardia y acidemia observadas.(AU)

Infusão contínua de fentanil e cetamina para controle de dor no transcirurgico: relato de caso / Continuous infusion of fentanyl and ketamine for trans-surgical pain control: case report

O paciente da espécie canina, sem raça definida, com 5 anos, deu entrada a clínica veterinária particular apresentando quadro de dor aguda e intensa em cavidade abdominal associada a prostração. Foram realizados exames de sangue, ultrassonografia e radiografia de abdômen, cuja suspeita foi torção parcial do estômago, com esplenomegalia, além de gastrite e enterite. O paciente foi submetido imediatamente ao procedimento cirúrgico para alívio, reposicionamento do órgão e gastropexia. O animal foi medicado previamente com metadona, tramadol e dipirona duas horas antes do ato cirúrgico, portanto não foram utilizadas medicações pré-anestésicas e optou-se pelo propofol e cetamina para a indução anestésica, além da infusão contínua com cetamina e fentanil para se obter a analgesia multimodal. Os parâmetros de dor foram avaliados por meio das frequências cardíaca e respiratória, traçado eletrocardiográfico, pressão arterial sistólica e média, aferição da temperatura retal e coloração de mucosas, a cada 5 minutos. Os mesmos indicaram boa estabilidade hemodinâmica, segurança e analgesia, sem necessidade de alterar as doses estabelecidas durante o procedimento. Pode ser observada também redução do requerimento de isoflurano para manutenção do plano cirúrgico. O paciente acordou sem sinais de dor no pós-operatório imediato evitando estresse sistêmico, o que conferiu o bom resultado do protocolo analgésico instituído.

The patient (Caramel) canine, mixed breed, approximately 5 years old, weighing 26kg was seen at the Ame Vet veterinary clinic, with severe abdominal pain, apathy, anorexia, prostration. Blood tests, abdominal ultrasound and abdominal x-ray were performed according to the tests a suspicion of partial torsion of the stomach and splenomegaly with right displacement, in addition to gastritis and enteritis. It was decided by the clinic and surgeon to perform laparotomy and prophylactic gastropexy. The animal was previously medicated by the clinic that treated the animal for analgesia with methadone, tramadol and dipyrone two hours before the beginning of the surgical procedure, therefore, pre-anesthetic medications, anesthetic induction with propofol, and ketamine were not used, aiming to perform analgesia. Multimodal with continuous infusion of ketamine and fentanyl, that is, more than one different mechanism of action, acting synergistically and reducing dose-dependent adverse effects and monitoring hemostasis and patient parameters, presenting its efficacy and safety in intraoperative pain control. The parameters addressed were heart rate (HR), respiratory rate (RR), electrocardiographic tracing, Spo2, systolic blood pressure (SBP), mean arterial pressure (MAP), temperature and mucosal color, evaluated every 5 minutes. The parameters evaluated indicated good hemodynamic stability, safety and analgesia, with no need to change the doses established during the procedure. A reduction in the requirement of isoflurane to maintain the surgical plan can also be observed. The patient woke up without signs of pain in the immediate postoperative period, thus avoiding systemic stress. which conferred the good result of the analgesic protocol instituted.

Ultrasonographic aspects of the uterus and ovaries of bitches during the estrous cycle paper review / Aspectos ultrassonográficos do útero e ovários de cadelas durante o ciclo estral revisão de literatura

The ultrasonographic exam is of great value in animal reproduction and veterinary obstetrics, because it allows gestational diagnosis and monitoring, as well as the evaluation of the female reproductive system, providing diagnosis of the reproductive state and estrous phase of females. One of the techniques that has been employed in the field of theriogenology is the Doppler Mode, which allows qualitative and quantitative evaluation of the hemodynamics of reproductive organs. Several studies were carried out in attempt to elucidate the ultrasonographic aspect of the uterus and ovaries of bitches during the different phases of the estrous cycle in B mode and Doppler mode. The objective of the present study is to review the information present in the literature regarding the sonographic changes of the reproductive organs of bitches during the different hormonal phases.(AU)

O exame ultrassonográfico tem grande importância na reprodução animal e obstetrícia veterinária, pois permite o diagnóstico e acompanhamento gestacional, bem como a avaliação do sistema reprodutor, proporcionando o diagnóstico do status reprodutivo e fase do ciclo estral. Uma das técnicas ultrassonográficas que vêm sendo empregadas no ramo da teriogenologia é o modo Doppler, que permite avaliações qualitativas e quantitativas da hemodinâmica dos órgãos da reprodução. Diversos estudos foram realizados na tentativa de elucidar o aspecto ultrassonográfico do útero e dos ovários das cadelas durante as diferentes fases do ciclo estral ao modo-B e ao modo Doppler. O presente trabalho tem como objetivo revisar as informações presentes na literatura a respeito das mudanças ultrassonográficas dos órgãos reprodutores da cadela durante as diferentes fases hormonais.(AU)

Ultrasonographic aspects of the uterus and ovaries of bitches during the estrous cycle – paper review / Aspectos ultrassonográficos do útero e ovários de cadelas durante o ciclo estral – revisão de literatura

The ultrasonographic exam is of great value in animal reproduction and veterinary obstetrics, because it allows gestational diagnosis and monitoring, as well as the evaluation of the female reproductive system, providing diagnosis of the reproductive state and estrous phase of females. One of the techniques that has been employed in the field of theriogenology is the Doppler Mode, which allows qualitative and quantitative evaluation of the hemodynamics of reproductive organs. Several studies were carried out in attempt to elucidate the ultrasonographic aspect of the uterus and ovaries of bitches during the different phases of the estrous cycle in B mode and Doppler mode. The objective of the present study is to review the information present in the literature regarding the sonographic changes of the reproductive organs of bitches during the different hormonal phases.

O exame ultrassonográfico tem grande importância na reprodução animal e obstetrícia veterinária, pois permite o diagnóstico e acompanhamento gestacional, bem como a avaliação do sistema reprodutor, proporcionando o diagnóstico do status reprodutivo e fase do ciclo estral. Uma das técnicas ultrassonográficas que vêm sendo empregadas no ramo da teriogenologia é o modo Doppler, que permite avaliações qualitativas e quantitativas da hemodinâmica dos órgãos da reprodução. Diversos estudos foram realizados na tentativa de elucidar o aspecto ultrassonográfico do útero e dos ovários das cadelas durante as diferentes fases do ciclo estral ao modo-B e ao modo Doppler. O presente trabalho tem como objetivo revisar as informações presentes na literatura a respeito das mudanças ultrassonográficas dos órgãos reprodutores da cadela durante as diferentes fases hormonais.

Comparison of the internal thoracic artery flow dissected by video endoscopy or conventional technique

ABSTRACT Purpose: To compare the blood flow in the internal thoracic artery when dissected endoscopically in a conventional manner, in addition to develop a reliable experimental training model for the surgical team. Methods: Paired experimental study. Ten pigs were operated and had both internal thoracic arteries dissected, the right with a conventional technique and the left by video endoscopy. The main outcomes to be studied were flow, length, and time of dissection of each vessel. Results: Blood flow measurements were performed with mean heart rate of 100 ± 16 bpm and mean arterial pressure of 89.7 ± 13 mm Hg. The mean blood flow of endoscopic dissection of the internal thoracic artery was 170.2 ± 66.3 mL/min and by direct view was 180.8 ± 70.5 (p = 0.26). Thus, there was no statistically significant difference between the flows, showing no inferiority between the methods. Conclusions: The minimally invasive dissection of the internal thoracic artery was shown to be not inferior to the dissection by open technique in relation to the blood flow in the present experimental model. In addition, the model that we replicated was shown to be adequate for the development of the learning curve and improvement of the endoscopic abilities.

B-mode and Doppler ultrasonography of abdominal structures of the peccary (Tayassu tajacu, Linnaeus 1758) / [Ultrassonografias Doppler e modo-B das estruturas abdominais de catetos (Tayassu tajacu Linnaeus, 1758)]

This study used B-mode and Doppler ultrasonography to characterize the abdominal structures of healthy peccaries raised in captivity. Fifteen peccaries were used for this study. The urinary vesicle appeared as an ovoid structure, located in the abdominal and pelvic transition, with a hyperechogenic, thin, smooth, and regular wall. The kidneys presented retroperitoneal topography and had similar sizes. The kidney/aorta ratio had an average value of 10.53±15cm (right) and 10.23±0.12 (left). The right adrenal gland had a length of 1.93±0.34cm and diameter of 0.56±0.16cm. The left adrenal gland had a length of 1.85±0.42cm and diameter of 0.52±0.11cm. The spleen had a diameter of 1.13±0.18cm. The hepatic vein demonstrated polyphasic flow in pulsed Doppler, with two retrograde peaks and an anterograde peak with a flow velocity of 25.7±0.83cm/s. The abdominal aorta had a diameter of 0.58±0.05cm and a flow velocity of 115.17±5.32cm/s. The morphological and hemodynamic study of the abdominal structures of the peccary, observed through B-mode and Doppler ultrasonography, aided in identifying the size, shape, position, echogenicity, and echotexture of the abdominal organs and in making inferences about the normal parameters for these structures in this species.(AU)

Este estudo teve como objetivo utilizar as ultrassonografias de modo-B e Doppler para caracterizar as estruturas abdominais de um cateto sadio criado em cativeiro. Quinze catetos foram utilizados para este estudo. A vesícula urinária apareceu como uma estrutura ovoide, localizada na transição entre as partes abdominal e pélvica, com uma parede hiperecogênica, fina, lisa e regular. Os rins apresentaram topografia retroperitoneal e tamanhos semelhantes. A relação rim/aorta teve um valor médio de 10,53 ± 15cm (direita) e 10,23 ± 0,12cm (esquerda). A glândula adrenal direita tinha um comprimento de 1,93 ± 0,34cm e um diâmetro de 0,56 ± 0,16cm. A glândula suprarrenal esquerda tinha um comprimento de 1,85 ± 0,42cm e um diâmetro de 0,52 ± 0,11cm. O baço tinha um diâmetro de 1,13 ± 0,18cm. A veia hepática demonstrou fluxo polifásico no Doppler pulsátil, com dois picos retrógrados e um pico anterógrado com velocidade de fluxo de 25,7±0,83cm/s. A aorta abdominal tinha um diâmetro de 0,58 ± 0,05cm e uma velocidade de fluxo de 115,17±5,32cm/s. Os estudos morfológico e hemodinâmico das estruturas abdominais do queixada, observadas por meio das ultrassonografias modo-B e Doppler, auxiliaram na identificação do tamanho, da forma, da posição, da ecogenicidade e da ecotextura dos órgãos abdominais e na realização de inferências sobre os parâmetros de normalidade para as estruturas nas espécies.(AU)

Ozonioterapia no tratamento auxiliar de éguas inférteis: Potencial angiogênico e antimicrobiano / Ozone therapy in the supporting treatment of infertile mares: Angiogenic and antimicrobial actions

A endometrite infecciosa é considerada uma das principais causas de infertilidade em éguas. Por sua vez, alterações degenerativas endometriais interferem diretamente na hemodinâmica uterina, podendo comprometer a fertilização e a manutenção da gestação. Por serem poderosos agentes oxidantes nãoespecíficos, o gás ozônio (O3) e os óleos vegetais ozonizados tem sido utilizados como alternativas às terapias antimicrobianas convencionais. Além de apresentar ação germicida frente a forma livre de fungos e bactérias, a ozonioterapia possui marcante potencial antibiofilme. Adicionalmente, o preenchimento da cavidade uterina de éguas com gás O3 estimula a angiogênese local sem apresentar efeitos deletérios ao endométrio. Dessa forma, os potencias antimicrobianos e angiogênicos fazem da ozonioterapia uma promissora alterativa para o tratamento adjuvante de endometrites crônicas em éguas.

Infectious endometritis is considered one of the main causes of infertility in mares. Similarly, endometrial degenerative changes directly affect the uterine hemodynamics, compromising the fertilization and the maintenance of pregnancy. Based on their powerful non-specific oxidizing action, ozone (O3) and ozonized vegetable oils have been used as alternatives to conventional antimicrobial therapies. In addition to the germicidal effect against the free-living cells of fungi and bacteria, O3 therapy has showed unspecific anti-biofilm potential. Additionally, the insufflation of the uterine cavity of mares with O3 stimulates local angiogenesis without inducing deleterious effects on the endometrium. Therefore, the antimicrobial and angiogenic potentials make O3 therapy a promising alternative for the adjuvant treatment of persistent endometritis in mares.

Evaluation of acute cardiorespiratory and hemodynamic changes in perioperative intravenous antimicrobial applications in cats / [Avaliação das alterações cardiorespiratórias e hemodinâmicas agudas em aplicações pré-operatórias de antimicrobianos, pela via intravenosa, em gatos]

The metabolic peculiarities of felines favor an intoxication. Fifty healthy female cats were divided into five groups: PG (placebo group), G2 (cefazolin), G3 (ceftriaxone), G4 (enrofloxacin) and G5 (ampicillin) were used. The parameters evaluated were: total expired carbon dioxide (ETCO2), oxygen saturation in hemoglobin (SpO2), heart rate (HR), respiratory rate (RR), body temperature (BT), systolic, mean and diastolic blood pressure (SBP, mBP and DBP) by invasive method, at T0, 5 (T5), 10 (T10), 15 (T15), 20 (T20), 25 (T25) and 30 (T30) minutes after administration of the treatments. HR presented reduction in G2 compared to PG at all times, except T20, and in G4, T25 and T30 were lower than the T0 values (P<0.05). BT showed increase in the G3 at T0 and T5 and all groups showed reduction in the values of BT relative to T0 (P<0.05). ETCO2 increased in G2 and G5 at all times compared to PG (P<0.05) and there were no differences among the times within each group. It was concluded that ceftriaxone is safer for the prophylactic antimicrobial use in cats, however the other antimicrobials are also indicated, because all the parameters, in all groups, basically did not change over the study and when this occurs it remains in reference interval.(AU)

As peculiaridades metabólicas dos felinos favorecem quadro de intoxicação. Foram utilizadas 50 gatas saudáveis, que foram divididas em cinco grupos: GP (grupo placebo), G2 (grupo cefazolina), G3 (grupo ceftriaxona), G4 (grupo enrofloxacina) e G5 (grupo ampicilina). Os seguintes parâmetros foram avaliados: dióxido de carbono expirado (ETCO2), saturação de oxigênio na hemoglobina (SpO2), frequência cardíaca (FC), frequência respiratória (FR), temperatura corporal (T°C), pressão arterial sistólica,média e diastólica (PAS, PAM e PAD), pelo método invasivo, em 0 (T0), 5 (T5), 10 (T10), 15 (T15), 20 (T20), 25 (T25) e 30 (T30) minutos após a administração dos tratamentos. A FC apresentou redução no G2 em relação ao GP em todos os momentos, exceto no T20, e, no G4, o T25 e o T30 foram inferiores aos valores do T0 (P<0,05). A T°C apresentou aumento no G3 no T0 e no T5, e todos os grupos apresentaram redução nos valores da T°C em relação ao T0 (P<0,05). O ETCO2 apresentou aumento no G2 e no G5, em todos os momentos, em relação ao GP (P<0,05). Concluiu-se que a ceftriaxona é mais segura para uso profilático em gatos, entretanto os outros antibióticos também são recomendados, pois todos os parâmetros praticamente não se modificaram e, quando alterados, mantiveram-se dentro dos padrões de referência.(AU)