How to critically appraise a paper

Critical appraisal skills enabling assessment of the validity and importance of evidence are essential for clinicians to make informed decisions regarding what new information should be incorporated into their clinical practice. This review highlights key points to consider in a critical review concentrating on common study designs used in the equine literature.     

Impact of hospitalization and antimicrobial drug administration on antimicrobial susceptibility patterns of commensal Escherichia coli isolated from the feces of horses

Objective-To evaluate antimicrobial susceptibility of commensal Escherichia coli strains isolated from the feces of horses and investigate relationships with hospitalization and antimicrobial drug (AMD) administration. Design-Observational study. Animals-68 hospitalized horses that had been treated with AMDs for at least 3 days (HOSP-AMD group), 63 hospitalized horses that had not received AMDs for at least 4 days (HOSP-NOAMD group), and 85 healthy horses that had not been hospitalized or treated with AMDs (community group). Procedures-Fecal samples were submitted for bacterial culture, and up to 3 E coli colonies were recovered from each sample. Antimicrobial susceptibility of 724 isolates was evaluated. Prevalence of resistance was compared among groups by use of log-linear modeling. Results-For 12 of the 15 AMDs evaluated, prevalence of antimicrobial resistance differed significantly among groups, with prevalence being highest among isolates from the HOSP-AMD group and lowest among isolates from the community group. Isolates recovered from the HOSP-AMD and HOSP-NOAMD groups were also significantly more likely to be resistant to multiple AMDs. Resistance to sulfamethoxazole and resistance to trimethoprim-sulfamethoxazole were most common, followed by resistance to gentamicin and resistance to tetracycline. Use of a potentiated sulfonamide, aminoglycosides, cephalosporins, or metronidazole was positively associated with resistance to 1 or more AMDs, but use of penicillins was not associated with increased risk of resistance to AMDs. Conclusion and Clinical Relevance-Results suggest that both hospitalization and AMD administration were associated with prevalence of antimicrobial resistance among E coli strains isolated from the feces of horses.     

Use of antiviral medications against equine herpes virus associated disorders

Numerous types of equine herpesviruses (EHV) continue to afflict horses resulting in a variety of clinical manifestations. While many of the clinical manifestations of EHV are self‐limiting or require only supportive care, some clinical expressions of EHV infections cause severe risk to the horse's overall health and can result in abortion, long‐term deficits or death. Antiviral medications are infrequently utilised therapeutics in equine medicine and their exact efficacy is largely unknown. However, the use of antiviral medications may potentially decrease convalescent time and improve outcome in horses with EHV‐related diseases. Thus, equine practitioners should consider the potential use of antiviral medications in the future. The purpose of this article is to familiarise the equine practitioner with current information in regard to antiviral medications and their potential uses in equine medicine.     

Antimicrobic and anthelmintic resistance.

Antimicrobial and anthelmintic resistance are growing issues for the equine practitioner. The development of antimicrobial or anthelmintic resistance is a source of significant concern because of increased frequency of treatment failures and increased treatment costs. In addition, antimicrobial resistance may have important consequences for public health. Only through judicious use can the efficacy of antimicrobials and anthelmintics be prolonged. This article discusses the development of resistance and suggestions for control.     

Application and indications of magnetic resonance imaging and computed tomography of the equine head

The equine head is an anatomically highly complex area affected by a range of disorders, making the diagnosis of head conditions challenging. Imaging techniques play a crucial role in the diagnostic work-up of head disorders. Tomographic imaging methods, such as computed tomography (CT) and magnetic resonance imaging (MRI) are particularly useful in avoiding problems associated with superimposition of multiple structures in this highly complex region. Both techniques are becoming more widely available in equine medicine. However, the choice between CT and MRI for imaging the equine head is not always straightforward. Each modality has advantages and disadvantages in terms of practicality, costs and diagnostic value for particular problems. The aim of this review is to describe the application of CT and MRI for imaging the equine head and to provide a practical guide for their use in different anatomical structures and clinical indications. This should allow the equine practitioner to make an informed decision on which modality to choose.     

Assessment of quality of life in equine patients

Reasons for performing study: Assessing patients' quality of life (QOL) is a core part of clinical decision making. Various methodologies for assessing patients' QOL have been developed in human medicine and small animal veterinary disciplines. In contrast, the lack of aids for QOL assessment in equine veterinary practice leaves practitioners reliant on subjective assessments of QOL, which may be prone to avoidable errors. Objectives: This paper suggests pragmatic ways in which QOL may be enhanced, while remaining appropriate for the time, financial and owner‐based constraints within equine practice. Methods: Through interdisciplinary research, this paper identifies, adapts and applies insights from several areas of research and practical experience in order to develop an overarching approach to making QOL‐based decisions in clinical cases. Results: The paper identifies 6 steps involved in QOL‐based decision making and provides examples of how these steps may be practically applied. These include deciding what each clinician feels is important; deciding how to evaluate it, including taking owners' views into consideration; making decisions about each case and achieving the desired clinical outcomes. Conclusions: Practitioners can draw their own conclusions on how they may improve QOL assessment in practice and may usefully share these with colleagues. Reporting cases and sharing practical examples of QOL tools used on the ground are vital to the development of this field and appropriate methodologies. Potential relevance: Improvements in QOL assessment are relevant to all areas of equine veterinary practice, and several areas of research. Further research may develop QOL assessment in practice, but more important are the personal improvements that each practitioner may achieve. See also correspondence by Grove     

Advances in diagnostic ultrasonography

A wide variety of ultrasonographic equipment currently is available for use in equine practice, but no one machine is optimal for every type of imaging. Image quality is the most important factor in equipment selection once the needs of the practitioner are ascertained. The transducer frequencies available, transducer footprints, depth of field displayed, frame rate, gray scale, simultaneous electrocardiography, Doppler, and functions to modify the image are all important considerations. The ability to make measurements off of videocassette recorder playback and future upgradability should be evaluated. Linear array and sector technology are the backbone of equine ultrasonography today. Linear array technology is most useful for a high-volume broodmare practice, whereas sector technology is ideal for a more general equine practice. The curved or convex linear scanner has more applications than the standard linear array and is equipped with the linear array rectal probe, which provides the equine practitioner with a more versatile unit for equine ultrasonographic evaluations. The annular array and phased array systems have improved image quality, but each has its own limitations. The new sector scanners still provide the most versatile affordable equipment for equine general practice.     

Medical treatment of osteoarthritis in the horse - a review

The medical treatment of osteoarthritis (OA) in the horse is one of the most utilized therapeutic regimens in the equine practice. It is important to understand the anatomy of synovial joints and the pathophysiology of the disease process to treat OA adequately. Once a thorough understanding of the disease process is comprehended the proper combination of systemic nonsteroidal anti-inflammatory drugs (NSAIDs), intraarticular steroids, viscosupplementation and chondroprotectants can be used to treat the disease and inhibit further progression of degenerative changes to the cartilage surface. The equine practitioner is faced with many choices for controlling inflammation in OA. This review presents the background and appropriate uses of various NSAIDs such as phenylbutazone, flunixin meglumine, ketoprofen, naproxen, and carprofen as well as their associated toxicities. Various steroid formulations exist for intraarticular (IA) administration and much has been learned in the past decade regarding correct dosage, frequency of administrations, indications and toxicity. This review presents IA steroids and their indications in addition to various chondroprotective drugs that also exist to control inflammation and provide viscosupplementation. Data are also given on disease modifying OA drugs such as glucosamine and chondroitin sulphate that have more recently become available to the equine practitioner.     

Principles of early wound management.

The equine practitioner can positively influence wound healing by dispensing appropriate treatment in the first few hours after injury.Positive actions in the early period include hemostasis, meticulous cleansing and debridement of the wound, the use of effective but nonirritating products to disinfect the wound, closure (if indicated)with minimal tension on the suture line, the judicious use of drains,and ensuring adequate tetanus protection. Furthermore, a thorough assessment of the wound and the patient in the initial period after trauma provides pertinent information on prognosis. Finally,good communication and cooperation among all involved parties are necessary to ensure that everyone understands the factors involved and the potential for a successful outcome.     

Equine bandaging techniques

Topical medications and bandages play an important role in the management of equine wounds. Certain water-soluble antibacterial ointments (povidone-iodine, polymixin-neosporin-bacitracin) may be appropriate for use on contaminated wounds. A well-designed equine bandage is usually composed of primary, secondary, and tertiary layers. Because so many different products are available, the practitioner is advised to become familiar with the handling characteristics of a few. Because of the irregular contours of the equine limb, only products that stretch and conform should be used. Bandages should be applied snugly and secured in such a fashion that they will not slip or ride up. The horse should be confined to a stall while bandaged, and, even then, bandages must be changed at frequent intervals.     

Use of complementary veterinary medicine in the geriatric horse.

The use of complementary and alternative veterinary medicine continues to grow within the veterinary community. As more clients seek out complementary and alternative medicine for their own health care, they begin to seek out these forms of therapy for their animals. For the equine practitioner, this includes those clients with geriatric animals. It is hoped that this article provides some insight into what conditions may be helped with CVM (complementary veterinary medicine) and when an equine practitioner may want to consider CVM as a form of therapy for the geriatric horse.     

Equine tapeworm infections: Disease,diagnosis and control

Equine tapeworm infection has gained increasing attention over the past few decades and a number of research studies have already been published. These focus primarily on the most common of the 3 tapeworm species, Anoplocephala perfoliata, although some new information has also been generated for the other two species, Anoplocephala magna and Anoplocephaloides mamillana. The preponderance of research studies have focused on development and validation of diagnostic techniques for tapeworm detection and the role of these parasites in equine gastrointestinal disease. Several diagnostic techniques have been found useful for diagnosis of A. perfoliata but each has its strengths and weaknesses. Egg counting techniques have been modified to achieve acceptable to good diagnostic performance but the trade‐off is often a more time‐consuming method. Validation studies indicate that these methods can reliably detect tapeworm burdens above 10 worms. Several enzyme‐linked immunosorbent assays (ELISAs) have been developed and made commercially available. These can generate useful information about tapeworm exposure on the herd level but are less reliable for individual diagnosis. Unfortunately, none of the available diagnostic techniques are useful for evaluating anthelmintic treatment efficacy. Coproantigen testing may find use as a future diagnostic modality but further characterisation is required. The large body of scientific evidence supports an association between A. perfoliata infection and certain types of equine colic, although some discrepancy exists between studies. Tapeworm surveillance and control should be considered as part of the overall parasite control strategy. When properly used, the currently available diagnostic tools can guide the veterinarian to make strategic decisions regarding tapeworm control.     

Survey of complications and antimicrobial use in equine patients at veterinary teaching hospitals that underwent surgery because of colic

OBJECTIVE: To determine current practices regarding use of antimicrobials in equine patients undergoing surgery because of colic at veterinary teaching hospitals. DESIGN: Survey. SAMPLE POPULATION: Diplomates of the American College of Veterinary Surgeons performing equine surgery at veterinary teaching hospitals in the United States. PROCEDURE: A Web-based questionnaire was developed, and 85 surgeons were asked to participate. The first part of the survey requested demographic information and information about total number of colic surgeries performed at the hospital, number of colic surgeries performed by the respondent, and whether the hospital had written guidelines for antimicrobial drug use. The second part pertained to nosocomial infections. The third part provided several case scenarios and asked respondents whether they would use antimicrobial drugs in these instances. RESULTS: Thirty-four (40%) surgeons responded to the questionnaire. Respondents indicated that most equine patients undergoing surgery because of colic at veterinary teaching hospitals in the United States received antimicrobial drugs. Drugs that were used were similar for the various hospitals that were represented, and for the most part, the drugs that were used were fairly uniform irrespective of the type of colic, whereas the duration of treatment varied with the type of colic and the surgical findings. The combination of potassium penicillin and gentamicin was the most commonly used treatment. CONCLUSIONS AND CLINICAL RELEVANCE: Results of this study document the implementation of recommendations by several authors in veterinary texts that antimicrobial drugs be administered perioperatively in equine patients with colic that are undergoing surgery. However, the need for long-term antimicrobial drug treatment in equine patients with colic is unknown.     

Equipping the avian practice.

The interest in avian medicine grows every year, and the degree of successful diagnosis and treatment in our avian patient has increased tremendously over the last 2 decades. For a veterinarian interested in avian practice there are many decisions to be made before one just accepts a patient. As outlined in this summary, there are many decisions to make regarding the level and diversity a practitioner wishes to explore (only exotics, poultry, ratites, Columbiforms, raptors, and so on) and then which equipment will be necessary to perform that level of practice. There is no master list of equipment that every avian practitioner must own. Needs must be catered to the species seen and the individual interest of the practitioner. Continuing education courses are now offered throughout the country on various aspects of avian medicine. The Association of Avian Veterinarians provides a journal, yearly conference, Web site, and a wide range of support materials. The author implores interested veterinarians to investigate these great learning experiences before casually deciding to add avian patients to a general companion animal practice.     

The use of sedatives,analgesic and anaesthetic drugs in the horse: An electronic survey of members of the American Association of Equine Practitioners (AAEP)

Reasons for performing study: To determine the sedative, analgesic and anaesthetic drugs and techniques that are used by equine veterinarians. Hypothesis or objectives: To provide equine veterinarians with information concerning veterinary use of anaesthetic techniques, a reflection of the collective experiences of the profession. Methods: A survey was conducted of those members of the American Association of Equine Practitioners (AAEP) with an electronic mail address on file with the organisation using proprietary, web‐based software. The survey was comprised of 30 questions divided into 8 sections: nonsteroidal anti‐inflammatory drugs; local anaesthesia; alternative techniques; standing chemical restraint; epidural anaesthesia; short‐term anaesthesia; long‐term anaesthesia; and a place for the respondent to make comments. Results: The response rate was 13.8% (952/6911) AAEP member veterinarians primarily use phenylbutazone and flunixin as anti‐inflammatory drugs, and lidocaine and mepivacaine for local anaesthesia. Combinations of drugs are preferred for standing chemical restraint. While many veterinarians frequently utilise short‐term anaesthesia, longer anaesthesia is less frequently performed. Conclusions: Most AAEP member veterinarians use sedatives in combination to provide standing chemical restraint. Extra‐label use of drugs is a core component of current equine sedation and anaesthetic practice. Potential relevance: Equine veterinarians can compare their choices of anaesthetic drugs with others practising equine medicine and surgery and may be stimulated to investigate alternative methods of providing comfort to horses.     

Perception of Equine Practitioners Regarding the Occurrence of Selected Equine Neurologic Diseases in the Northeast Over a 10-Year Period

A survey was developed to examine the perception of equine practitioners regarding the occurrence of five equine neurologic diseases in the northeastern United States over the 10-year period between June 1, 1997 and June 1, 2007. This information was then compared with trends at Cornell University's Equine Hospital during the same time span, which in general agreed with practitioners' opinions. Equine herpes virus-1 (EHV-1) neurologic disease, equine motor neuron disease (EMND), and equine protozoal myelitis (EPM) have historic and current relevance. Results showed that the frequency of EMND and EPM has remained relatively stationary or decreased somewhat, whereas the frequency of the neurologic strain of EHV-1 may have increased slightly over the last decade. Less historical information on clinical disease associated with Borrelia burgdorferi infection (Lyme disease) and Parelaphostrongylus tenuis exists; however, results suggest that P. tenuis in the equine is presently emergent. Opinions regarding the existence and rate of occurrence of clinical borreliosis in horses appear divided. A better understanding of the frequency with which these diseases occur, as well as possible associated positive risk factors, will aid the equine practitioner in making an appropriate diagnosis in cases of neurologic disease in their equine patients.     

Essential considerations for equine oral examination, diagnosis, and treatment

Equine dentistry should no longer be thought of as art over science. To be an effective equine dental clinician requires considerable investment in knowledge beyond the basic veterinary degree. It requires current scientific dental knowledge and adherence to the fundamental principles of medicine, dentistry, and surgery. Knowledge and principles will provide clinicians with the necessary information to make more evidence-based decisions as the scientific literature continues to evolve. Diagnosis and therapy should be seen as journeys with a destination, keeping in mind the values of the Hippocratic oath. Equine dentistry no longer needs to be seen as hard physical work with considerable risk to all involved. There is a demand for providers of equine dental care to be appropriately trained veterinarians and for veterinarians to further develop the science of equine dentistry. The rewards to the horse, client, and clinician are likely to be evident to those who make the investment.