Abdominal perfusion in canine patients with pyometra and sepsis evaluated by Doppler and contrast-enhanced ultrasound.

BACKGROUND: Sepsis is a condition characterized by organic dysfunction, leading to hemodynamic instability and high morbidity and mortality rates in humans and animals. Early identification of perfusion changes and appropriate management of sepsis are crucial for improving patient prognosis. Currently, the Systemic Inflammatory Response Syndrome (SIRS) and Sequential Organ Failure Assessment (SOFA) scores are widely studied for sepsis identification and evaluation of organ dysfunction. However, these scores do not assess gastrointestinal involvement, which is common in this condition. Contrast-enhanced ultrasound (CEUS) and Doppler have been considered promising diagnostic techniques for detecting changes in vascularization and microcirculation in a non-invasive and safe manner, particularly in the gastrointestinal system. This study aimed to evaluate duodenal perfusion using CEUS, as well as abdominal aortic and cranial mesenteric artery blood flow using Doppler ultrasound, and systolic arterial pressure (SAP) in 17 bitches with pyometra and in 10 healthy animals. RESULTS: The variables were compared between the pyometra and control groups, as well between patients with and without sepsis determined by the SOFA or SIRS scores. Pyometra was found to cause a reduction in abdominal aortic blood flow volume, aortic peak systolic velocity, and resistivity index as evaluated by Doppler ultrasound. Patients with sepsis according to the SOFA criteria only presented lower SAP. In contrast, sepsis animals identified by the SIRS score exhibited lower SAP, aortic peak systolic velocity, aortic blood flow volume, and aortic resistivity index and additionally, higher peak intensity of contrast in the duodenal wall. CONCLUSIONS: Pyometra causes a reduction in abdominal aortic blood flow, which is more pronounced in animals with sepsis identified by the SIRS criteria. These animals also exhibited a decrease in systolic blood pressure and an increase in duodenal perfusion, as evident by CEUS. However, these changes were not observed in patients with sepsis identified by the SOFA criteria. The alterations in intestinal perfusion observed in animals with sepsis indicate the presence of inflammation or dysfunction. In this regard, CEUS proves to be a valuable technique for detecting subtle changes in tissue hemodynamics that may not be apparent in conventional exams.

Maternal and fetal ultrasonography, vulvar temperature and vaginal mucous impedance for the prediction of parturition in Saanen does.

The aim of this study was to evaluate and correlate modifications of vaginal mucous impedance, vulvar temperature and ultrasonographic measurements (echobiometric parameters) to parturition in pregnant Saanen does. 30 does were selected for the study and submitted to an estrus synchronization protocol and natural mating. The females were evaluated daily from Day 143 of pregnancy to parturition. For the sonographic evaluations, the following structures were measured: biparietal diameter, thoracic diameter, abdominal diameter, ocular orbit, kidney length, kidney height, cardiac area, placentome length, cervical measurement and fetal heart rate; by means of two different approaches: transrectal and transabdominal, using a 7.5 MHz linear transducer. The vaginal mucous impedance was assessed using an electric estrous detector and vulvar temperature was measured using a non-contact infrared thermometer. Statistical analysis was performed using the R-project software and the significance level was set at 5% for all tests. 25 Saanen does became pregnant, resulting in 80.33% pregnancy rate. Fetal heart rate was negatively correlated to the hours to parturition (p<0,001; r-Pearson= -0,451), as well as vaginal temperature (p= 0,001; r-Pearson= -0,275), while cervical thickness was positively correlated to hours to parturition (p<0,001; r-Pearson= 0,490). The echobiometric parameters (biparietal diameter, thoracic diameter, abdominal diameter, ocular orbit, kidney length and height, cardiac area, placentome length), as well as vaginal mucous impedance did not vary throughout the timepoints of evaluation and did not correlate to the moment of parturition. It was concluded that the parameters of fetal heartbeat, vaginal temperature and cervical effacement in the last week of pregnancy provide valuable information regarding the proximity of parturition.

Accuracy of B-mode ultrasound and ARFI elastography in predicting malignancy of canine splenic lesions.

The objective was to evaluate the accuracy of B-mode ultrasonography and ARFI elastography in detecting malignancy in canine splenic lesions. Thirty-seven spleens with abnormalities (16 benign and 21 malignant) from dogs of different breeds and ages were evaluated. Echogenicity, echotexture, organ length and height were evaluated using B-mode. By ARFI elastography, tissue stiffness was evaluated qualitatively (elastogram) and quantitatively (measuring the shear wave velocity-SWV). Lesions were classified as diffuse, focal or multifocal (cranial, medial or caudal portion) and comparisons of the SWV between the injured and non-injured areas were performed. In the B-mode, no features were associated to malignancy (P > 0.05). In the elastogram, 35 spleens were non-deformable and 2 deformable, having no association with malignancy. The greater SWV was observed in malignant lesions (3.4 ± 0.6 m/s), followed by areas free from alterations (2.1 ± 0.3 m/s) and benign lesions (1.7 ± 0.5 m/s), with difference between groups (P < 0.0001). It was found that a SWV > 2.6 m/s indicates malignancy of canine splenic lesions (sensitivity of 95%, specificity of 100%, PPV of 100%, NPV of 94% and accuracy of 97%), concluding that ARFI elastography is a promising technique for differentiating malignancy in these lesions.

Doppler sonography of the umbilical and uterine arteries blood flow of pregnant Saanen goats.

The objective was to evaluate the blood flow of the uterine artery (UA) and umbilical artery (UMB) in the physiological pregnancy of goats by means of Doppler throughout the gestational period. Twenty-five Saanen goats weighing 55 ± 10 kg and aged between 2 and 5 were evaluated weekly, from the 21st until the 143rd day of gestation, and daily from that period until parturition. Values for peak systolic velocity (PSV), end diastolic velocity (EDV) and resistance (RI) and pulsatility (PI) indices of the uterine and umbilical arteries were determined. The values obtained were correlated with gestational age by Spearman's test, tested for adjustment to regression models and compared with the number of fetuses by ANOVA. The umbilical cord was first visualized at 28 days. Of the variables evaluated, RIUMB and PIUMB correlated with gestational age (p<0.001; and 0.046; respectively) and RIUMB had a low negative correlation with the number of fetuses per pregnancy (p = 0.003; r- Spearman = - 0.218). PSVUMB and EDVUMB values did not correlate with gestational age (p=0.737 and 0.768, respectively), but there was a decrease in the mean values throughout pregnancy (PSVUMB= 0.07; 0.31 and EDVUMB= 0.01; 0.06) as well as the change in the flow pattern of the spectral trace. The mean values of the uterine artery dopplervelocimetric variables PSVUT, EDVUT, PIUT and RIUT did not correlate with gestational age (p= 0.324; 0.372, 0.143; 0.13; respectively). It is expected that the results obtained will contribute to a broader understanding of the hemodynamic changes resulting from pregnancy in goats.

Ovarian contrast-enhanced ultrasonography and Doppler fluxometry in bitches during the postovulatory estrus and corpora lutea formation.

The aim of the present study was to evaluate the vascularization features of canine ovaries during the follicular phase and the formation of the corpora lutea by using Doppler ultrasonography and Contrast-Enhanced Ultrasound (CEUS). Eight healthy bitches were enrolled in the study and were evaluated at five different timepoints (T1 - T5) of the estrous cycle established by vaginal cytology and serum progesterone concentration. Ultrasonographic examinations were performed by a single operator using the ACUSON S2000/SIEMENS machine equipped with a linear multifrequency transducer (9.0 MHz). Color-coded Doppler evaluation of the ovarian parenchyma was performed to investigate the aspects of the signal detection throughout the different timepoints. Pulsed-wave Doppler of the intraovarian arteries was performed to evaluate spectral waveform and doppler velocimetric parameters of Systolic Peak Velocity (SPV cm/s), End Diastolic Velocity (EDV cm/s), Resistivity Index (RI) and Pulsatility Index (PI). CEUS evaluation of the ovaries was performed using a vascular contrast agent (SonoVue®, Bracco, Sao Paulo, Brazil) and the CADENCE™ Contrast Pulse Sequencing (CPS, Siemens) software, in order to perform both qualitative and quantitative analysis. Perfusion parameters of pixel number, peak intensity (PPI in %), time to peak intensity (TTP in s), mean transit time (MTT in s) and area under the curve (AUC in %). Colour-coded Doppler evaluation demonstrated an increase in signal detection as cycle progressed, with blood flow initially detected with few coloured pixels and mainly at the ventral surface of the ovaries. Further on, the number of coloured pixels increased and spreading to the central region, resulting in a circular-like pattern around the corpora hemorrhagica. The spectral waveform was consistent at all timepoints. SPV (cm/s) and EDV (cm/s) presented a numeric trend and a slight statistical difference at all timepoints, whereas no difference was found for RI and PI. CEUS evaluation demonstrated an increase in pixel intensity across all the timepoints. Quantitative CEUS analysis revealed a statistical difference in PPI (%), MTT (s) and AUC (%) at T5. CEUS evaluation of the ovaries was feasible and demonstrated a marked increase in perfusion parameters in the late postovulatory period, demonstrating its applicability in the assessment of canine corpora lutea development.

B-mode ultrasound and ecobiometric parameters to assess embryonic and fetal development and estimate gestational age in goats.

The aim of this study was to monitor maternal-fetal ecobiometric parameters during physiological pregnancy in goats using ultrasound to predict gestational age by establishing mathematical equations. Twenty-five Saanen goats were included in the study. Assessments were performed weekly from the 21st day of pregnancy until parturition. The abdominal, thoracic, biparietal, and eye socket diameters; distance from the neck to snout; crown-rump, humerus, radius-ulna, metacarpal, femur, tibia, metatarsal, and placentome lengths; kidney height and length; and heart area were measured. Heart rate was obtained using the pulsed Doppler mode. The variables were correlated with gestational age using Spearman's test, and the adjustment of these variables to simple and multiple regression models was done to determine the mathematical formulas for calculating the gestational age. The highest obtained coefficients of determination (R2) were for humerus length (96.2), heart area (95.6), and distance from the neck to the snout (95.3). Only the placentome length and fetal heart rate presented low determination coefficients (R2 = 54.3, R2 = 45.0). The results indicated significant correlations between measures of maternal-fetal structures and gestational age, and can be used as reference values for detection of abnormalities during fetal development.