Clinical, Hematological, Blood Gasometric and Electrolytic Changes in Dogs Receiving Whole Blood Transfusions

Background: Blood transfusion is a tool capable of saving lives. Patients undergoing blood transfusion usually present several alterations in the acid-base and electrolyte balance, aggravating the condition of critically ill patients. Some studies have demonstrated haematological alterations in certain species that received whole blood transfusions, however, few studies have evaluated acid base and electrolyte changes in dogs undergoing whole blood haemotherapy. The aim of this study was to analyze clinical, hematological, blood gas and electrolyte changes in anemic dogs after whole blood transfusion.Materials, Methods & Results:Twenty nine dogs transfused due to anemia were enrolled in the study. Donors blood was collected in a transfusion bag containing citrate phosphate adenine dextrose and stored up to 24 h. Blood collections and evaluations were made before and 24 h after the transfusion. Data distribution normality was tested by the Shapiro Wilk Test. The means of the variables were compared by paired t-test. It was observed an increase in diastolic blood pressure and a reduction in heart rate (P 0.05) and ionized calcium (P > 0.05) and an increase in the mean partial pressure of carbon dioxide (pCO2) (P 0.05) and sodium (P < 0.05). The probable cause of anemia was monocytic ehrlichiosis (14/29), visceral leishmaniasis (1/29), babesiosis (1/29), co-infection of Ehrlichia canis and Leishmaniainfantum (2/19), co-infection of E. canis and Babesia vogeli (1/19). It was not possible to determine the etiology of the anemia in ten dogs. Discussion:Heart rate significantly reduced after transfusion, probably because of the increase in hematocrit, hemoglobin and erythrocyte values. It may be justified by the displacement of extravascular fluid to the intravascular space. Mean values of systolic blood pressure were slightly elevated before transfusion and remained elevated afterwards, while diastolic and mean arterial pressure increased significantly after transfusion. These changes may be due to the morbid condition and may be influenced by many other factors. Haematocrit, haemoglobin and erythrocyte values increased significantly after transfusion, according to what was observed in other studies. The significant reduction in pH and increase in pCO2 reflects the compensatory mechanism for metabolic acidosis to increase ventilation, leading to pCO2 reduction and changes in pH. The reduction in pH due to the contact of the collected blood with conservative solutions is one of the main changes thar occurs during blood storage. It was described significantly lower pH in dogs’ whole blood samples stored for more than 24h in vacutainer plastic containing CPDA-1. We may assume there was no intense pH reduction in the present study because the bags were stored for up to 24 h. Although not statistically significant, the increase of pO2 mean reflects the improvement of tissue oxygen perfusion. It was observed a significant increase in sodium ions. The mean sodium ionconcentration before transfusion was very close to the maximum reference value. Hyperkalaemia was not observed, nor was there significant reduction of potassium ions after transfusion. Several studies report hyperkalaemia and transfusion-associated cardiac arrests in humans, associated with infusion of large volumes of blood. Whole blood transfusion increased erythrogram values and did not negatively affect the electrolyte or acid-base status, representing a safe and useful tool in the intensive care of small animals.

Molecular prevalence and factors associated with Ehrlichia canis infection in dogs from the North Pantanal wetland, Brazil

Background and Aim: Canine monocytic ehrlichiosis is a vector-borne disease caused by the obligatory intracellular bacterium Ehrlichia canis, which is distributed across tropical and subtropical regions worldwide. Its prevalence within dog populations is high in municipalities located across the Pantanal biome, but it remains unknown in Barão de Melgaço, Mato Grosso, Brazil. This study aimed to determine the molecular prevalence and factors associated with E. canis infection in dogs domiciled in Barão de Melgaço. Materials and Methods: A cross-sectional study was carried out to investigate the prevalence of E. canis infection in 369 dogs from urban and rural areas in Barão de Melgaço, North Pantanal wetland, Brazil. Initially, the dogs were examined, and, through a questionnaire, the risk factors were investigated. Blood samples were subjected to DNA extraction and PCR was performed to estimate the prevalence of E. canis infection. Results: The molecular prevalence of E. canis infection in dogs was 42.5% and none of the studied variables were significantly associated with polymerase chain reaction (PCR) positivity (p > 0.05). Conclusion: The high molecular prevalence demonstrates an increased transmission of the agent across the city. This also indicates that attention needs to be paid to E. canis infection and control measures should be introduced to prevent its transmission. The demographic and clinical risk factors commonly associated with E. canis infection in this study were not associated with PCR positivity