The use of a tongue tie alters laryngohyoid position in the standing horse.

REASONS FOR PERFORMING STUDY: The use of tongue ties in racing is common, yet there are few data to support their efficacy. In order to make appropriate recommendations for clinical practice and policy on tongue ties, data documenting their effect on upper airway structure are necessary. OBJECTIVES: To determine the effect of a tongue tie on the resting laryngohyoid position of the standing horse. STUDY DESIGN: Experimental study. METHODS: Twelve normal Standardbred horses were subjected to ultrasonographic measures of laryngohyoid position during 3 phases of tack application: Phase I--halter and lead; Phase II--bit, bridle, harness and check applied; and Phase III--as in Phase II but with the tongue tie added. RESULTS: Compared to Phase I, during Phase III with the application of a tongue tie a significant difference between lingual process position was noted both rostrally and caudally (P<0.001 and P<0.001), such that the tongue tie resulted in an increase in lingual process depth. The tongue tie in Phase III resulted in a decrease in depth of the thyroid cartilage and basihyoid bone compared to the Phase I location (P = 0.007 and P = 0.0047). CONCLUSION: The use of a tongue tie has a significant effect on the basihyoid and thyroid cartilage positions in the standing horse. POTENTIAL RELEVANCE: This is the first report documenting a difference in laryngohyoid morphology following the application of a tongue tie, providing evidence that the use of a tongue tie has a measurable effect on upper airway structure. The functional implications of this finding are yet to be elucidated.

Results of upper airway radiography and ultrasonography predict dynamic laryngeal collapse in affected horses.

REASONS FOR PERFORMING STUDY: The pathogenesis of dynamic bilateral laryngeal collapse (DLC) associated with poll flexion is unknown. Diagnosis is dependent upon exercise endoscopy while replicating the flexed head position harness racehorses experience during racing. OBJECTIVES: To describe the effects of poll flexion on rostrocaudal laryngeal positioning and laryngeal lumen width in resting horses diagnosed with DLC compared to controls, and to establish diagnostic criteria for DLC by use of diagnostic imaging. STUDY DESIGN: Case-control study. METHODS: Fifty harness racehorses were prospectively included in the study: 25 cases diagnosed with DLC by treadmill endoscopy and 25 controls in which treadmill endoscopy revealed no abnormal findings. Laryngeal radiography and ultrasonography were obtained in neutral and flexed head positions. Laryngeal positioning and laryngohyoid conformation were compared between the groups and head positions. RESULTS: Poll flexion induced a greater rostral advancement of the larynx in relation to the hyoid apparatus in resting harness racehorses affected with DLC compared to controls (P = 0.007). At the level of the vocal folds, poll flexion resulted in a smaller laryngeal lumen width in horses affected with DLC compared to controls (P = 0.04). Horses were significantly more likely to be affected with DLC when the thyrohyoid bone to thyroid cartilage distance was ≥12 mm in poll flexion (odds ratio 21.3, 95% confidence interval 3.65-124.8, P = 0.004) and when laryngeal lumen width at the level of the vocal folds was less in poll flexion than in the neutral head position (odds ratio 8.4; 95% confidence interval 1.6-44.1, P = 0.012). CONCLUSIONS AND POTENTIAL RELEVANCE: In DLC horses, poll flexion advanced the larynx more rostrally and resulted in a decreased airway lumen width compared to control horses. Laryngeal ultrasound and radiography may facilitate the diagnosis of DLC at rest.

A novel treatment for dynamic laryngeal collapse associated with poll flexion: the modified checkrein.

REASONS FOR PERFORMING THE STUDY: Dynamic laryngeal collapse (DLC) associated with poll flexion is a performance limiting dynamic upper airway disorder commonly diagnosed in Coldblooded trotters. An inspiratory obstruction occurs when affected horses are driven with tension on the reins, inducing poll flexion. To date, surgical treatment and conservative management have failed to improve racing performance in affected horses. OBJECTIVES: To test the efficacy of an external device, the modified checkrein, in limiting poll flexion, diminishing laryngeal collapse and improving airway mechanics when horses are driven on a treadmill with tension on the reins and test the hypothesis that the modified checkrein will limit poll flexion thereby improving endoscopic appearance of the larynx and reduce airway obstruction in harness racehorses affected with DLC. METHODS: Fourteen Norwegian Coldblooded trotter (NCT) racehorses previously diagnosed with DLC associated with poll flexion exercised on a high-speed treadmill at speeds that resulted in heart rate >200 beats/min. Upper airway videoendoscopy recordings, tracheal pressures and video recordings of the head and neck position were collected while horses exercised with the conventional checkrein on Day 1 and the modified checkrein on Day 2. RESULTS: The modified checkrein successfully limited poll flexion as measured by no change in head position parameters between phases of no rein tension and phases of rein tension. Endoscopic scores were significantly improved (arytenoids cartilage collapse P<0.0001; vocal fold collapse P<0.0001) and tracheal peak inspiratory pressures were significantly less negative (P = 0.0162) when horses were fitted with the modified checkrein compared to the conventional checkrein. CONCLUSIONS AND POTENTIAL RELEVANCE: The modified checkrein successfully limited poll flexion and also prevented upper airway obstruction in NCT horses affected with DLC associated with poll flexion. The modified checkrein seems promising in offering a method of conservative management in harness racehorses affected with this disorder.

Spinal deformity in triploid grass carp Ctenopharyngodon idella (Valenciennes).

From mid-2004 to mid-2005, several grass carp, Ctenophayngodon idella (Valenciennes), showing evidence of spinal deformity were presented to the Aquatic Animal Health Program, Cornell University. The carp were from three separate locations in New York State. The first case involved several fish from a natural body of water in the Catskill Mountain region of south-eastern New York State. The second was a single affected individual from a private pond in the Fingerlakes region of Central New York State. The third was a single individual from the Cold Springs Harbor Fish Hatchery, Cold Springs Harbor, Long Island. All fish were at least 7 years of age. Radiographs and computed tomography (CT) scans revealed the deformities to be of bony origin. The spinal deformities were characterized by variable amounts of kyphosis, scoliosis and rotation. While it is not possible to determine the specific cause(s) of the lesions, we consider a genetic component as a likely contributor to the observed pathology.

Effect of poll flexion and dynamic laryngeal collapse on tracheal pressure in Norwegian Coldblooded Trotter racehorses.

REASON FOR PERFORMING STUDY: Dynamic laryngeal collapse (DLC) associated with poll flexion is a newly diagnosed upper respiratory tract obstructive disorder that causes poor racing performance. OBJECTIVES: To determine if Norwegian Coldblooded Trotters (NCTs) affected with DLC associated with poll flexion differ from normal, elite NCTs based on simple airway mechanics measurements. METHODS: Five normal elite NCTs and 6 NCTs diagnosed previously with DLC underwent treadmill videoendoscopy while tracheal pressures were measured continuously. Alternating head positions were used such that horses were exercised with free head carriage and induced poll flexion at heart rates >200 beats/min. RESULTS: Peak inspiratory tracheal pressures were significantly more negative for horses with DLC compared to the elite horses. This difference was only significant during the exercise phases when the poll region was flexed, P = 0.0015. Head position significantly affected peak inspiratory pressure for both elite and affected horses, P < 0.0001. CONCLUSIONS AND CLINICAL RELEVANCE: Induced poll flexion significantly affected peak inspiratory pressure (PIP) in all horses; however, PIPs were significantly more negative in those affected with DLC. Based upon the tracheal pressure measurements recorded in this study, DLC in NCTs is a severe obstructive upper respiratory tract disorder that is induced by poll flexion.

Ultrasonography of the equine larynx.

Nasopharyngeal and laryngeal evaluation is important when examining horses with upper airway signs for poor performance. Currently endoscopy is the most common method to evaluate the equine upper airway. Ultrasonography of the equine larynx has not previously been described. Using six cadaveric specimens and four standing horses, the ultrasonographic appearance of the equine larynx was established. A scanning technique, including useful acoustic windows and the normal ultrasonographic appearance at each site, is described. Ultrasound allowed visualization of portions of the hyoid apparatus, laryngeal cartilages, associated soft tissues, and intrinsic and extrinsic laryngeal musculature, that are not seen using endoscopy. Additionally, real-time ultrasound allowed observation of the movement of the vocal folds and the arytenoid cartilages during respiration. In three horses with arytenoid chondritis, ultrasonography aided in the diagnosis and localization of arytenoid abcessation and perilaryngeal inflammation. The establishment of this technique will serve as the basis for future investigations in the evaluation of clinical patients with upper airway abnormalities.

Identifying removable radioactivity on the surface of cats during the first week after treatment with iodine 131.

Because radioiodine (1-131) is excreted in urine and saliva, treated cats can accumulate I-131 on their coats from contacting soiled litter and grooming. This could result in removable radioactivity, which is a potential source of human exposure to radiation and specifically to internal contamination. The purpose of this study was to determine if there is removable radioactivity on cats treated with I-131. Daily wipe tests were performed for 7 days at two sites (both flanks, one site; and all four paws, one site) on six hyperthyroid cats treated with I-131. A y counter was used to determine the counts per minute (cpm) of the samples, which were converted to disintegrations per minute (dpm) to estimate activity. The results were compared to the New York State limits of removable activity for a non-controlled area (<1000dpm/100 cm2) to determine if the amount of removable activity was acceptable for a member of the public. The median value of removable activity was 241 dpm (range from 34 to 4184 dpm) for the flanks, and 308 dpm (range from 60 to 1890 dpm) for the paws. The amount of removable radioactivity on the surface of hospitalized cats treated with I-131 during the first week after treatment, occasionally and without obvious pattern, exceeded the New York State limit. Sporadic activity as high as 4148 dpm was found. It is prudent to advise owners to observe routine hygiene when handling cats after discharge to minimize the risk of internal contamination.

Accredited work-based learning: an approach for collaboration between higher education and practice.

This article discusses the experience of creating a programme of accredited work based learning (AWBL) for emergency nurse practitioners (ENPs) who work in an Accident and Emergency (A&E) Department in the North East of England. The initiative highlighted the challenges of collaboration with purchasers of education and with professional colleagues, other than nurses. Accredited work-based learning was seen to be an appropriate means of supporting ENP role development. Some of the drivers of the development were: the need for a rapid response to wide ranging changes in the health service; the need to ensure rigour in the quality of both education and health care; to enable participants to engage in role development with appropriate skills, confidence and competence; and to ensure that the learning programme had parity in its design with conventional university based learning. The aim was to collaborate in the creation of learning which was relevant to the Trust's drive to improve patient care which accommodated the nurses' common and individual learning needs and offered academically recognized learning opportunities in tune with the post-Dearing ethos in higher education. This aim was reached and included a great deal of learning on the part of the collaborating partners.

Theories and models of nursing and the nursing process.

In summary, nursing models can be evaluated by carefully considering how human beings are conceptualised within a model, how adequately the model guides nurses in the decision-making associated with all stages of the nursing process and how appropriate is the expected role of the nurse. Reference to the criteria for evaluating nursing theory (Fig. 1) demonstrates that not only can nursing models be regarded as the precursors of nursing theory but some evaluative criteria for nursing theory develop from ways of evaluating nursing models (Fig. 2). The essence of this paper has been to consider nursing theory and its place in the current climate of concern both about nursing's professional status and about standards of patient care. The difficulty in defining theory has been briefly explored and suggestions have been made of possible ways of evaluating nursing theory. A distinction has been drawn between nursing models and nursing theory with a rationale for considering nursing models as precursors of nursing theory especially as there are similarities in the criteria used to evaluate them both. The nursing process has been described as a systematic, problem-solving approach to care. It is neither a nursing model nor a theory but rather one way of organising nursing activities. A major dilemma has been omitted from this paper, however, which nonetheless deserves mention here. This dilemma is identified and summarised by Jacox (1974) among others. The question posed is: Can and should we develop nursing theories?' (Jacox's emphasis). The main competing arguments put forward by Jacox are on the one hand that there are no phenomena or activities peculiar to nursing around which nursing theory can develop, and on the other hand that there is a need for a specified body of knowledge to inform nursing practice. Efforts to establish a firmer body of knowledge on which to base nursing practice may help to identify the unique function of the nurse. This will only be achieved if practising nurses take a keen interest in developing rigorous approaches to the evaluation of nursing models and theories. Craig (1980) has linked theory development and its integration with nursing practice to professional survival. If nurses cannot identify phenomena and activities that are peculiar to nursing and if they are not prepared to safeguard these areas of practice, then the future of nursing looks bleak. Project 2000 (UKCC 1986) offers an opportunity for nurses to be more willing and able to critically consider nursing's unique contribution to health care.

Models of nursing, nursing practice and nurse education.

Over the last few years, and concurrent with wider debates about the quality of patient care, increasing numbers of practising nurses and nurse educators have expressed interest in using conceptual models of nursing as a basis for planning and delivering nursing care. In the light of such interest, this paper identifies the distinctive features of three fundamental types of nursing model and explores the implications of these for contemporary approaches to nursing practice and nurse education.