Treatment and outcomes of two pigs treated for hemoabdomen secondary to splenic disease.

OBJECTIVE: To report the management and outcomes of two pigs undergoing emergency surgery for hemoabdomen secondary to splenic disease. STUDY DESIGN: Case report. ANIMAL: Two adult pigs with hemoabdomen and suspected splenic pathology. METHODS: Pigs were admitted for several clinical signs including lethargy, inappetence, vomiting, abdominal distention, hypothermia, and tachycardia. Abdominal ultrasound and abdominocentesis led to a diagnosis of hemoabdomen secondary to splenic disease. RESULTS: The spleen was confirmed as the source of hemorrhage during midline exploratory celiotomy in both pigs. Splenic rupture resulted from splenic vein thrombosis in one pig and splenic torsion in the other. Complications included intraoperative hemorrhage and intraabdominal adhesion formation. Four years following splenectomy, one pig was euthanized because of widespread small intestinal adhesions causing luminal obstruction, while the other pig was euthanized following a diagnosis of chronic myeloid leukemia. CONCLUSIONS: A ventral midline celiotomy provided adequate exposure for splenectomy. The procedure allowed resolution of signs in both pigs. Splenic pathology, such as vessel thrombosis or torsion, may result in splenic rupture and should be considered as a differential in pigs with hemoabdomen.

Interpreting abdominal fluid in colic horses: Understanding and applying peritoneal fluid evidence.

BACKGROUND: Interpreting changes in peritoneal fluid helps clinicians manage colic and other diseases in horses. During abdominal problems in the horse, abdominal fluid characteristics such as color, turbidity, total nucleated and red blood cell counts, cytology, total protein, and l-lactate change in predictable ways, helping the clinician characterize the disease. DESCRIPTION: Normal abdominal fluid in horses is odorless, clear to light yellow in color, and transparent. Peritoneal fluid becomes more turbid with increasing levels of protein, number of WBCs or RBCs, or with gross contamination following intestinal rupture. The color of abdominal fluid will also change with the type and quantity of cells or other elements present. The transformation of peritoneal fluid color from golden to orange to red represents increasing levels of RBCs, common with strangulating intestinal lesions. Serosanguinous defines fluid that is both turbid and orange to bloody because of increased total protein, WBCs, and RBCs, and is considered classic for diseases characterized by intestinal ischemia. Peritoneal fluid may also be red or blood-colored because of a hemoperitoneum, or secondary to blood contamination during sample collection. l-Lactate measurement in the abdominal fluid has proven invaluable for the identification of strangulating intestinal injury. Cytology acts as an important supplement to cell counts in peritoneal fluid, and the normal ratio of non-degenerate neutrophils:mononuclear cells of 2:1 changes during various gastrointestinal diseases. Culture of peritoneal fluid samples should be performed when septic peritonitis is suspected. SUMMARY: Abdominal fluid is a sensitive indicator of intestinal injury and a useful tool to direct treatment. Peritoneal fluid evaluation includes gross visual and olfactory examination, nucleated cell count, total protein, RBC count, lactate levels, cytology, and culture. The changes noted in such variables are related to the type and duration of the abdominal problem. KEY POINTS:  Abdominal fluid interpretation has become central to the triage and management of challenging equine colic patients.  The transformation of peritoneal fluid color from golden to orange to red represents increasing levels of RBCs, common with strangulating intestinal lesions.  Contamination with RBCs at various concentrations may be secondary to vascular (eg, abdominal wall or mesenteric vessels) or splenic trauma during abdominal fluid collection; however, this must be distinguished from orange to red fluid associated with intestinal strangulating obstruction or hemoabdomen  Peritoneal fluid analysis reveals abdominal pathology by recognizing specific changes that occur with disease processes affecting the tissues and organs within this cavity.  Abdominal fluid examination should be used as a tool to direct treatment rather than the definitive test for diagnosis of the acute abdomen  Septic peritonitis in horses most commonly originates secondary to intestinal compromise or accidents (vascular damage, perforation, or surgical manipulation), leading to bacterial translocation into the abdomen.

Abdominocentesis techniques in horses.

BACKGROUND: Abdominocentesis is commonly used to evaluate the abdominal cavity of the horse. This technique provides valuable diagnostic information as well as the means to monitor patients with abdominal diseases being managed medically and to determine their need for surgical management. Complications are uncommon and include trauma to the gastrointestinal tract or spleen, septic peritonitis, or abdominal wall infection. PROCEDURES: This review describes the indications, utility, patient preparation, and instructions for performing abdominocentesis as well as possible complications reported in horses. Step-by-step instructions are provided for the two most commonly used abdominocentesis techniques in horses, which include the use of a needle (18 Ga, 3.8 cm [1.5 in]) and a teat cannula (9.5 cm [3.75 in]). SUMMARY: Peritoneal fluid collection and fluid analysis can be used to confirm diagnosis of intraabdominal pathology including inflammatory, infectious, neoplastic, obstructive, and bowel strangulation, leading to additional diagnostic and therapeutic plans. KEY POINTS: Abdominocentesis is useful as a diagnostic procedure in horses suffering from colic, diarrhea, weight loss, or other conditions involving the abdominal cavity and is an integral component of diagnostic testing for colic at referral institutions or in the field. Abdominal fluid collection using an 18-Ga, 3.8-cm (1.5-in) needle is recommended for adult horses because the needle is long enough to penetrate the peritoneal cavity. The teat cannula technique is recommended for use in adult horses, foals, and miniature horses to reduce the risk of enterocentesis, even though this procedure is more traumatic than using an 18-Ga, 3.8-cm needle. Ultrasonography of the abdomen is a valuable tool in the assessment of any horse with signs of colic, but it is not essential for performing an abdominocentesis successfully.

Calculating and selecting fluid therapy and blood product replacements for horses with acute hemorrhage.

BACKGROUND: Blood products, crystalloids, and colloid fluids are used in the medical treatment of severe hemorrhage in horses with a goal of providing sufficient blood flow and oxygen delivery to vital organs. The fluid treatments for hemorrhage will vary depending upon severity and duration and whether hemorrhage is controlled or uncontrolled. DESCRIPTION: With acute and severe controlled hemorrhage, treatment is focused on rapidly increasing perfusion pressure and blood flow to vital organs. This can most easily be accomplished in field cases by the administration of hypertonic saline. If isotonic crystalloids are used for resuscitation, the volume administered should be at least as great as the estimated blood loss. Following crystalloid resuscitation, clinical signs, HCT, and laboratory evidence of tissue hypoxia may help determine the need for a whole blood transfusion. In uncontrolled hemorrhage, crystalloid resuscitation is often more conservative and is referred to as "permissive hypotension." The goal of "permissive hypotension" would be to provide enough perfusion pressure to vital organs such that function is maintained while keeping blood pressure below the normal range in the hope that clot formation will not be disrupted. Whole blood and fresh frozen plasma in addition to aminocaproic acid are indicated in most horses with severe uncontrolled hemorrhage. SUMMARY: Blood transfusion is a life-saving treatment for severe hemorrhage in horses. No precise HCT serves as a transfusion trigger; however, an HCT < 15%, lack of appropriate clinical response, or significant improvement in plasma lactate following crystalloid resuscitation and loss of 25% or more of blood volume is suggestive of the need for whole blood transfusion. Mathematical formulas may be used to estimate the amount of blood required for transfusion following severe but controlled hemorrhage, but these are not very accurate and, in practice, transfusion volume should be approximately 40% of estimated blood loss. KEY POINTS: Modest hemorrhage, <15% of blood volume (<12 mL/kg), can be fully compensated by physiological mechanisms and generally does not require fluid or blood product therapy. More severe hemorrhage, >25% of blood volume (> 20 mL/kg), often requires crystalloid or blood product replacement, while acute loss of greater than 30% (>24 mL/kg) of blood volume may result in hemorrhagic shock requiring resuscitation treatments Uncontrolled hemorrhage is a common occurrence in equine practice, and is most commonly associated with abdominal bleeding (eg, uterine artery rupture in mares). If the hemorrhage can be controlled such as by ligation of a bleeding vessel, then initial efforts to resuscitate the horse should focus on increasing perfusion pressure and blood flow to organs as quickly as possible with crystalloids or colloids while assessing need for whole blood transfusion. While fluid therapy is being administered every effort to physically control hemorrhage should be made using ligatures, application of compression, surgical methods, and local hemostatic agents like collagen-, gelatin-, and cellulose-based products, fibrin, yunnan baiyao (YB), and synthetic glues Although some synthetic colloids have been shown to be associated with acute kidney injury in people receiving resuscitation therapy,20 this undesirable effect in horses has not been reported.

Collection and administration of blood products in horses: Transfusion indications, materials, methods, complications, donor selection, and blood testing.

BACKGROUND: Blood transfusion is a lifesaving treatment for horses with acute hemorrhage and other causes of anemia. Transfusions improve oxygen delivery to the tissues via increased blood volume and hemoglobin concentration. Certain aspects of equine blood transfusion are challenging, especially in the field situation, and practitioners may be unfamiliar or feel overwhelmed with the process. An understanding of the indications, materials, methods, and techniques as well as donor selection and possible complications will help practitioners successfully implement blood transfusion in clinical practice. PROCEDURES: Blood transfusion involves several steps including appropriate donor selection, cross-matching, blood collection, and administration, as well as monitoring and handling of transfusion reactions. Guidance for each of these steps are detailed in this review. SUMMARY: Blood transfusion is an effective and often lifesaving treatment for managing diseases of blood loss, hemolysis, and decreased RBC production. Equine practitioners require a thorough understanding of the indications for blood transfusion, the immunological principles behind compatibility testing and transfusion reactions, and the technical skills to aseptically collect and administer blood products KEY POINTS: Equine practitioners require a thorough understanding of the indications for blood transfusion, the immunological principles behind compatibility testing and transfusion reactions, and the technical skills to aseptically collect and administer blood products. Because there are over 400,000 possible equine RBC phenotypes, no universal donor exists, and some blood type incompatibilities are likely between any donor and recipient. Therefore, prior to any blood transfusion, donor and recipient blood should be cross-matched Inadequate delivery of oxygen (Do2 ) to the tissues, resulting from low hemoglobin (Hb) concentration, is the most important indication for blood transfusion Neonatal isoerythrolysis most commonly occurs following an anamnestic response in late gestation; it rarely occurs following a primary exposure because the immune response is not strong enough to produce clinically significant alloantibody titers.

The pathophysiology of uncontrolled hemorrhage in horses.

BACKGROUND: Hemorrhagic shock in horses may be classified in several ways. Hemorrhage may be considered internal versus external, controlled or uncontrolled, or described based on the severity of hypovolemic shock the patient is experiencing. Regardless of the cause, as the severity of hemorrhage worsens, homeostatic responses are stimulated to ameliorate the systemic and local effects of an oxygen debt. In mild to moderate cases of hemorrhage (<15% blood volume loss), physiological adaptations in the patient may not be clinically apparent. As hemorrhage worsens, often in the uncontrolled situation such as a vascular breach internally, the pathophysiological consequences are numerous. The patient mobilizes fluid and reserve blood volume, notably splenic stored and peripherally circulating erythrocytes, to preferentially supply oxygen to sensitive organs such as the brain and heart. When the global and local delivery of oxygen is insufficient to meet the metabolic needs of the tissues, a cascade of cellular, tissue, and organ dysfunction occurs. If left untreated, the patient dies of hemorrhagic anemic shock. CLINICAL IMPORTANCE: An understanding of the pathophysiological consequences of hemorrhagic shock in horses and their clinical manifestations may help the practitioner understand the severity of blood volume loss, the need for referral, the need for transfusion, and potential outcome. In cases of severe acute uncontrolled hemorrhage, it is essential to recognize the clinical manifestations quickly to best treat the patient, which may include humane euthanasia. KEY POINTS: Uncontrolled hemorrhage may be defined as the development of a vascular breach and hemorrhage that cannot be controlled by interventional hemostasis methods such as external pressure, tourniquet, or ligation. Causes of uncontrolled hemorrhage in horses may be due to non-surgical trauma, surgical trauma, invasive diagnostic procedures including percutaneous organ biopsy, coagulopathy, hypertension, cardiovascular anomaly, vascular damage, neoplasia such as hemangiosarcoma, toxicity, or idiopathic in nature. When a critical volume of blood is lost, the respondent changes in heart rate, splenic blood mobilization, and microcirculatory control can no longer compensate for decreasing oxygen delivery to the tissues In spite of organ-specific microvascular responses (eg, myogenic responses, local mediator modulation of microvasculature, etc), all organs experience decreases in blood flow during severe hypovolemia Acute, fatal hemorrhagic shock is characterized by progressive metabolic acidosis, coagulopathy, and hypothermia, often termed the "triad of death," followed by circulatory collapse.

Transnasal, Endoscopically Guided Skull-Based Surgery by Pharyngotomy for Mass Removal from the Sphenopalatine Sinus in a Horse.

OBJECTIVE: To report a transnasal, endoscopically guided ventral surgical approach for accessing the cranial and caudal segments of the sphenopalatine sinus for mass removal in a horse. STUDY DESIGN: Case report. ANIMAL: Adult horse with acute onset blindness referable to a soft tissue mass within the sphenopalatine sinus. CLINICAL REPORT: A 7-year-old Warmblood gelding presented with a history of running into a fence and falling. No neurologic signs were identified at initial examination but acute blindness was noted 3 weeks later. On computed tomography (CT) the sphenopalatine sinus was filled with a large homogeneous mass with poor contrast enhancement that extended dorsally with thinning to the dorsal cortex of the sphenoid bone, just rostral to the entrance of the optic canals into the cranial cavity. Surgical access to the sphenopalatine sinus was achieved using a transnasal, endoscopically guided ventral pharyngotomy approach and the mass lesion was removed. A presumptive diagnosis of chondroma was made based on histopathology. The horse recovered well from surgery, and although it has not regained vision as of 6.5 years postoperatively, the disease has not progressed. CONCLUSION: Transnasal, endoscopically-guided ventral surgical access to the sphenopalatine sinus is possible in horses and may improve access in horses with disease extending caudally beyond the palatine portion of the sinus. Use of smaller diameter or specialized instruments, such as various endoscopic bone cutting instruments, and CT image guidance may improve sinus access by this route.

The clinical value of whole blood point-of-care biomarkers in large animal emergency and critical care medicine.

OBJECTIVE: To summarize the current medical literature and provide a clinical perspective of whole blood point-of-care (POC) biomarkers in large animal emergency and critical care practice. DATA SOURCES: Original studies, reviews, and textbook chapters in the human and veterinary medical fields. SUMMARY: POC biomarkers are tests used to monitor normal or disease processes at or near the patient. In both human and veterinary medicine these tools are playing an increasingly important role in the management of critical diseases. The most important whole blood POC biomarkers available for veterinary practitioners include l-lactate, cardiac troponin I, serum amyloid A, triglyceride, creatinine, and glucose, although many other tests are available or on the horizon. CONCLUSION: Whole blood POC biomarkers enable clinicians to provide improved management of critical diseases in large animals. These tools are especially useful for establishing a diagnosis, guiding therapy, and estimating disease risk and prognosis.

Laparoscopic-guided compared to skilled instructor support for student rectal examination training using live horses in the veterinary curriculum.

OBJECTIVES: To evaluate the veterinary student learning outcome of 2 methods of equine rectal examination training. STUDY DESIGN: Randomized prospective study. SAMPLE POPULATION: Veterinary students (3rd and 4th year; n = 40) and practicing equine veterinarians (n = 10). METHODS: Year 1: Group 1 (n = 11) and Group 2 students (n = 10) received skilled instructor (SI) and laparoscopic-guidance (LG), respectively, during rectal exam instruction. All students were tested on rectal identification of 4 abdominal organs. Year 2: One group of students (n = 19) was trained and subsequently tested using each technique, first SI, followed by LG. Subjective evaluation of laparoscopy as a teaching tool was achieved with veterinary students and equine practitioners. RESULTS: A significantly greater percentage of students having LG compared to SI were able to correctly identify the left kidney (Year 1) and the spleen, cecum, and right ovary (Year 2). A significantly greater proportion of LG trained students in years 1 and 2 (100% and 95%, respectively) were also able to identify 75% of organs compared with SI (27% and 21%, respectively). Both students and veterinarians uniformly provided favorable feedback for LG in teaching rectal palpation skills. CONCLUSION: The LG method of equine rectal examination instruction resulted in improved learning for identification of several key abdominal organs compared with SI.

Evaluation of L-lactate and cardiac troponin I in horses undergoing emergency abdominal surgery.

OBJECTIVE: To evaluate changes in plasma cardiac troponin I (cTnI) and L-lactate (LLt) as prognostic indicators in horses undergoing emergency abdominal surgery. DESIGN: Prospective observational study. SETTING: Veterinary teaching hospital. ANIMALS: Thirty-four horses undergoing emergency abdominal surgery. INTERVENTIONS: Serial blood sampling during various times during hospitalization (hospital admission, and 12, 24, 48, and 72 h postoperatively) evaluating cTnI and LLt concentrations. MEASUREMENTS AND MAIN RESULTS: All horses required surgery for correction of a strangulating (n = 29) or nonstrangulating obstruction (n = 5) of the small or large intestine. Twenty-seven horses survived to discharge; 7 were euthanized either during (n = 1) or after (n = 6) surgery due to disease severity or systemic complications associated with the primary gastrointestinal lesion. Preoperative cTnI concentrations were increased above the normal reference interval in 24% of horses (8/34, median = 0.01 ng/mL, range = 0-12.23 ng/mL), whereas LLt concentrations were increased above the normal reference interval in 88% of horses (30/34, median = 3.37 mmol/L, range = 0.77-13.26 mmol/L). The LLt concentration was significantly higher (P < 0.05) in nonsurviving compared with surviving horses at admission, and at 24 and 72 hours postoperatively. No significant difference in the cTnI concentration was detected between groups at admission. However, the cTnI concentration was significantly higher (P<0.05) in nonsurviving compared with surviving horses at all time points postoperatively. CONCLUSIONS: Measurement of both LLt and cTnI concentrations may provide information for prognostication in surgical colic horses. Marked increases in admission concentrations of LLt (median 7.56 mmol/L) and even moderate postoperative increases in cTnI concentration (median 0.97 ng/mL) may both indicate a poor prognosis in critically ill horses following abdominal surgery.

A comparison of epidural buprenorphine plus detomidine with morphine plus detomidine in horses undergoing bilateral stifle arthroscopy.

OBJECTIVE: To compare the analgesic efficacy of buprenorphine plus detomidine with that of morphine plus detomidine when administered epidurally in horses undergoing bilateral stifle arthroscopy. STUDY DESIGN: Prospective, randomized, blinded clinical trial. ANIMALS: Twelve healthy adult horses participating in an orthopedic research study. Group M (n = 6) received morphine (0.2 mg kg(-1)) and detomidine (0.15 mg kg(-1)) epidurally; group B (n = 6) received buprenorphine (0.005 mg kg(-1)) and detomidine (0.15 mg kg(-1)) epidurally. METHODS: Horses received one of two epidural treatments following induction of general anesthesia for bilateral stifle arthroscopy. Heart rate (HR), mean arterial blood pressure (MAP), end-tidal CO(2) (Pe'CO(2)), and end-tidal isoflurane concentrations (E'Iso%) were recorded every 15 minutes following epidural administration. Post-operative assessment was performed at 1, 2, 3, 6, 9, 12, and 24 hours after standing; variables recorded included HR, respiratory rate (f(R)), abdominal borborygmi, defecation, and the presence of undesirable side effects. At the same times post-operatively, each horse was videotaped at a walk and subsequently assigned a lameness score (0-4) by three ACVS diplomates blinded to treatment and who followed previously published guidelines. Nonparametric data were analyzed using Wilcoxon's rank-sum test. Inter- and intra-rater agreement were determined using weighted kappa coefficients. Statistical significance was set at p

Arthroscopic removal of palmar/plantar osteochondral fragments from the proximal interphalangeal joint in four horses.

OBJECTIVE: To describe anatomic considerations and arthroscopic technique in horses for arthroscopic removal of palmar/plantar osteochondral fragments from the proximal interphalangeal (PIP) joint. STUDY DESIGN: Retrospective study. ANIMALS: Adult horses (n=4) with osteochondral fragments of the palmar/plantar PIP joint. METHODS: Arthroscopic removal of palmar/plantar osteochondral fragments within the PIP joint was performed with horses in dorsal recumbency under general anesthesia. Medical records of affected horses were reviewed to determine history; physical, lameness, and radiological findings; surgical technique; complications and outcome. RESULTS: Two horses had lameness localized to the PIP joint. Two other horses had lameness suspected, but not confirmed to the pastern region. One of these horses had a history of intermittent lameness, but was not lame on admission. All horses had radiographic evidence of palmar/plantar osteochondral fragmentation within the PIP joint. Fragmentation was located abaxially in 2 horses in the hind limb and axially in 2 horses in the left forelimb. Osteochondral fragments were successfully removed via a palmar/plantar arthroscopic approach in all horses. Three horses returned to previous levels of athletic performance; 1 horse was used for trail riding instead of reining. CONCLUSIONS: Arthroscopy of the palmar/plantar pouch of the PIP joint allowed limited assessment of the joint and removal of osteochondral fragments. CLINICAL RELEVANCE: Arthroscopy of the palmar/plantar PIP joint pouch for assessment and removal of osteochondral fragments is possible and should be considered when lameness is localized to this joint.

Cylindrical press-fit osteochondral allografts for resurfacing the equine metatarsophalangeal joint.

OBJECTIVE: To investigate the feasibility of resurfacing the equine fetlock joint using cylindrical, orthotopic, press-fit, osteochondral allografts. STUDY DESIGN: Experimental study. ANIMALS: Ten mature, mixed-breed horses. METHODS: Cylindrical, osteochondral grafts (6.5-mm diameter) were harvested aseptically from cadaveric equine metatarsophalangeal joints. Allografts were transplanted into 6 horses; 4 horses were sham operated. The surgical approach involved creation of a bone block at the origin of the medial collateral ligament and luxation of the metatarsophalangeal joint. Grafts were placed into the medial and lateral metatarsal condyles. Radiographs were taken at 8 and 25 weeks, and lameness was evaluated at 25 weeks. Horses were killed at 25 weeks. Analyses included gross evaluation, microradiography, paravital staining, light microscopy, and cartilage biochemistry. RESULTS: No complications occurred that could be attributed to the surgical procedure. Graft congruency with the surrounding articular cartilage was fair to excellent. Two horses were sound at 25 weeks. Most grafts had more than 90% articular cartilage coverage, and histologic and microradiographic analysis revealed good graft incorporation and articular cartilage survival. Sulphated glycosaminoglycan concentration was decreased in grafted tissue. CONCLUSIONS: We attribute the viability of osteochondral allografts in the equine fetlock to adequate congruency, stable graft fixation, and the use of orthotopic tissue. Host response to the allograft bone tissue did not affect cartilage viability. CLINICAL RELEVANCE: Before clinical use, improvements to instrumentation are required that would decrease damage to grafts and minimize technique-associated incongruencies of the articular surface at the time of grafting. Larger grafts would also likely be required to resurface a greater surface area.