Comparison of different head and neck positions and behaviour in ridden elite dressage horses between warm-up and competition

Summary Head and neck position (HNP) has been identified in literature as important influence on wellbeing. It was investigated in ridden elite dressage horses whether there is a relation between the HNP, ethological indicators and the grading in the warm-up area and in the test. 49 starters (83%) of a Grand-Prix Special (CDIO5 *) as part of the CHIO in Aachen 2018 and 2019 were examined. For each horse-rider pair, HNP (angle at vertical (AT), poll angle (PA), neck angel (NA)) used were analysed as well as conflict behavior for 3 minutes each in warm-up area and test. 6571 individual frames were used. The noseline was carried significantly less behind the vertical in test vs. warm-up (5.43 ° ± 4.19 vs. 11.01 ° ± 4.54 behind the vertical; T = 34.0; p < 0.05). The horses showed significantly less conflict behavior in the test vs. warm-up (123 ± 54 vs. 160 ± 75) (T = 76.00; p < 0.01). In the latter, a smaller PA and more defensive behaviour of the horses was observed compared to the test. A correlation between the grading of test and HNP was found (R = 0.38; p < 0.05). The further the noseline was behind the vertical, the higher was the chance of a good rating. The higher riders were ranked in the “FEI world ranking”, the higher were their marks in the competition (2018: r = -0.69, p < 0.05; 2019: r = -0.76, p < 0.05). Horses of riders higher in world ranking tended to show more unusual oral behaviour (r = -0.30, p < 0.05), and a noseline stronger behind the vertical (r = -0.37, p < 0.05) resulting in a smaller NA (r = 0.43, p < 0.05). This are from the point of view of animal welfare problematic results.

Effects of Head and Neck Position on Nasotracheal Tube Intracuff Pressure: A Prospective Observational Study

To prevent endotracheal tube-related barotrauma or leakage, the intracuff pressure should be adjusted to 20–30 cm H2O. However, changes in the nasotracheal tube intracuff pressure relative to neck posture are unclear. In this study, we investigated the effect of head and neck positioning on nasotracheal tube intracuff pressure. Fifty adult patients with nasotracheal tubes who were scheduled for surgery under general anesthesia were enrolled. Following intubation, intracuff pressure was measured by connecting the pilot balloon to a device that continuously monitors the intracuff pressure. Subsequently, the intracuff pressure was set to 24.48 cm H2O (=18 mmHg) for the neutral position. We recorded the intracuff pressures based on the patients’ position during head flexion, extension, and rotation. The initial intracuff pressure was 42.2 cm H2O [29.6–73.1] in the neutral position. After pressure adjustment in the neutral position, the intracuff pressure was significantly different from the neutral to flexed (p < 0.001), extended (p = 0.003), or rotated (p < 0.001) positions. Although the median change in intracuff pressure was <3 cm H2O when each patient’s position was changed, overinflation to >30 cm H2O occurred in 12% of patients. Therefore, it is necessary to adjust the intracuff pressure after tracheal intubation and each positional change.

¿Cambia realmente la localización de la membrana cricotiroidea medida en posición neutra con la extensión de la cabeza y cuello? La ecografía nos abre los ojos.

El abordaje quirúrgico de urgencia de la vía aérea ante una situación “no intubable – no ventilable” es un escenario que implica, por parte del anestesiólogo, un adecuado entrenamiento que posibilite una resolución exitosa en el menor tiempo posible. Dada la poca frecuencia de esta práctica, muchos anestesiólogos optan por localizar la membrana cricotiroidea antes de realizar la inducción anestésica con la cabeza y cuello en posición neutra. Ante esto, y, considerando la posición ideal para una cricotiroidotomía al paciente con la cabeza y cuello en extensión, los autores de este artículo tratan de determinar si existe realmente cambio en la localización de dicha membrana con la variación de la cabeza y cuello de posición neutra a extendida así como si se modifica la altura de la misma. Para ello, realizan un estudio observacional con 22 voluntarios sanos a los que un radiólogo, con más de quince años de experiencia, mide con ecografía la distancia entre los bordes superior e inferior de la membrana y realiza una marca en el punto medio de la misma en las dos posiciones antes citadas. Los resultados obtenidos nos llevan a una importante reflexión que nos conduce a un cambio en el paradigma clásico de abordaje de la cricotiroidotomía. ABSTRACT Does the cricothyroid membrane location really change with the extension of the head and neck from neutral position? Ultrasound opens our eyes. The emergency surgical approach of the airway to a situation "can’t intubate, can’t oxygenate’ is a scenario implies an adequate training on the part of the anesthesiologist that enables a successful resolution in the shortest posible time. In view of the low frequency of this practice, many anesthesiologists choose to locate the cricothyroid membrane before performing the anesthetic induction with the head and neck in a neutral position. Considering this and that the ideal position for a cricothyroidotomy is placing the head and neck in extension, the authors of this article try to determine if there is a change in the location of the membrane with the variation of the head and neck position from neutral to extended as well as if the height of the membrane is modified. To do this, hey performed an observational study with 22 healthy volunteers to whom a radiologist with more than fifteen years of experience measures with ultrasound the distance between the upper and lower membrane edges and makes a mark at the midpoint of the same in the two positions mentioned above. The results obtained from the study lead us to an important reflection that leads us to a change in the classical paradigm of approach of the cricothyroidotomy.

The Pattern of Superficial Body Temperatures in Leisure Horses Lunged with Commonly Used Lunging Aids

Background: The natural head and neck position (HNP) of horses differs from the position in horse riding when bit is used. The special lunging aids (LAs) are applied in order to modify HNP. Different types of LAs have the potential to affect the work of horse muscles and the superficial thermographic patterns (STPs). The effects of thre LAs on STPs of neck, chest, back, and hindquarters were investigated. Methods: Sixteen leisure horses were lunged with freely moving head (FMH), rubber band (RB), chambon (CH), and triangle side reins (TRs). The thermographic images (n = 896) were analyzed before/after lunging for mean temperatures (Tmean) and minimum–maximum difference (Tdiff). Results: Superficial Tmean increased (p < 0.001) in cranial part of neck, back, thoracic area, and limbs after lunging regardless of LAs application or its type. In comparison to other LAs: With RB, Tmean was higher in regions of interest (ROIs) 2,7 and lower in ROIs 3–4 (p < 0.05); with CH, Tmean was higher in ROIs 2–4 and 7 (p < 0.01); and with TRs, Tmean was higher in ROIs 2–4,7,9–11 (p < 0.01). In ROIs 2–4 and 7, Tdiff was lower with LAs than with FMH (p < 0.01) and in ROIs 9–10 with TRs. Conclusions: The choice of LAs should be dictated by the expected effect; however, all LAs increase the quality of the leisure horse lunging. LA use is more desirable than lunging with FMH.