Shock in horses refers to a critical condition characterized by inadequate blood flow and oxygen delivery to tissues, often resulting from trauma, severe dehydration, or systemic infections. This physiological state can lead to organ dysfunction and requires prompt veterinary intervention. Shock is categorized into different types, such as hypovolemic, septic, and cardiogenic, each with distinct causes and clinical presentations. Recognizing the signs of shock, such as rapid heart rate, weak pulse, and altered mentation, is essential for timely treatment. This page aggregates peer-reviewed research studies and scholarly articles that explore the pathophysiology, diagnosis, and management of shock in equine patients.
Snow DH, Bogan JA, Douglas TA, Thompson H.The oral administration of phenylbutazone at a dose rate of approximately 10 mg per kg per day for seven to 14 days resulted in the development of signs of toxicity in seven of eight ponies treated. Clinical signs included anorexia, depression and abdominal oedema. Blood biochemical determinations showed a decrease in total plasma protein and calcium concentrations with an increase in urea concentration. These changes were considered indicative of water retention. Three of the ponies died during treatment following the development of shock. Shock was considered to arise from the submucosal oed...
Harkema JR, Robinson NE, Scott JB.Twelve Shetland ponies were fed a high-starch ration. Seven ponies which had a transitory metabolic acidosis developed laminitis 56 hours (+/- 3.5, SEM) after overfeeding. These ponies also developed persistent hypokalemia, hyperthermia, and increased heart rate 24 hours before the onset of lameness. Serum sodium, serum chloride, hematocrit, plasma volume, and blood volume were unchanged. At the onset of clinical signs of laminitis, cardiac output and blood pressure increased, but total peripheral resistance was unchanged. None of the measured or calculated values predicted the onset of lamini...
Veenman JN, Dujardint CL, Hoek A, Grootendorst A, Klein WR, Rutten VP.Equine acute abdominal disease is often associated with shock. Important aspects in the onset of this complication include hypovolaemia, the translocation of endotoxins from the gut and the subsequent activation of the cytokine network. The clinical efficacy of high volume continuous venovenous haemofiltration (HV-CVVH) and the clearance of cytokines were therefore investigated in an equine endotoxaemic model. Ten male Shetland ponies received a slow infusion of LPS (2 microg/kg bwt) under general anaesthesia. The treatment group (n = 5) received HV-CVVH (2 ml/kg bwt/min) using a 75 kD polymet...
Raisbeck MF, Garner HE, Osweiler GD.Gram negative endotoxins play a contributory role in the syndrome which results from over consumption of carbohydrates by horses and ponies. Since the antibiotic polymyxin B exerts a direct anti-endotoxin effect by chemically modifying the active lipid A moiety of endotoxin, it might be expected to protect horses after carbohydrate overload and provide a new therapeutic and experimental tool for this condition. The present study was undertaken to evaluate the effect of polymyxin B on hemostatic, hemodynamic, acid-base, and clinical aspects of the syndrome resulting from carbohydrate overload. ...
Moore AB, Roesel OF, Fessler JF, Bottoms GD.The value of naloxone (1 mg/kg of body weight/hr for 4 hrs), a beta-endorphin antagonist, was assessed in the management of endotoxin-induced shock in ponies. Three groups of 5 ponies each were used: controls, ponies given Escherichia coli endotoxin put untreated, and ponies given endotoxin and then treated with naloxone. Endotoxin-induced changes in hemodynamics, blood chemical values, regional blood flow, plasma enzymes, and energy supplies were measured at selected times during the first 6 hours after endotoxin was given. There was no evidence that beta-endorphins released during shock were...
Hermann M, Bretscher R, Thiébaud G, Meister D.HAES Steril 10% is a colloidal plasma expander rarely used in veterinary medicine. In this study HAES was used in clinical cases for the treatment of shock and in a comparative hypervolemic hemodilution study (HAES versus lactated Ringer's solution) using two experimental horses. Injection of a HAES volume equivalent to 10% of estimated blood volume resulted in a highly significant drop in PCV and in a significant drop in total protein concentration. Half live of HAES was approximately two hours. No incompatibility reactions were observed. In man HAES improves microcirculation. Studies in prog...
Katz LM, Ragle CA.Horses with tears that involve all layers of the rectum except the mesocolon (grade IIIb) have a poor prognosis for survival because of the difficulty in treating these wounds and the propensity for them to progress to full perforations (grade IV). Most treatments for grade-IIIb rectal tears involve surgery of some kind, but not all grade-IIIb rectal tears require surgical intervention. We report on 4 horses with grade-IIIb rectal tears that were evaluated via palpation per rectum and endoscopy. Two of 4 horses were admitted with signs consistent with shock and endotoxemia, and evaluation of a...
El-Menyar A, Khan NA, Naqvi SGA, Al-Thani H.The large animal-related injuries are emerging major trauma but remain underestimated public health problem worldwide. We aimed to determine the incidence, clinical characteristics, mechanisms and patterns of horse and camel-related injuries (HCRIs) in a Middle Eastern country. Methods: A retrospective analysis of all patients who were hospitalized due to HCRIs was conducted. Data included patient's demographics, mechanism of injury, anatomical location and severity of injury, and hospital outcomes. Results: Between November 2007 and December 2021, there were 273 hospitalized patients with HCR...
