INTRODUÇÃO: O carcinoma papilífero da glândula tireoide é a neoplasia maligna endócrina mais prevalente com incidência em torno de 95%. Apresenta alto índice de disseminação linfática cervical, principalmente para os linfonodos do compartimento central ipsilateral, no nível VI, sendo os paratraqueais e os pré-traqueais os mais acometidos. Porém, existe uma área específica, não descrita nos compêndios anatômicos, que também é sede de metástase e de recidiva tumoral e está localizada entre o nervo laríngeo recorrente direito e as artérias carótida comum direita e tireóidea inferior direita. Uma abordagem cirúrgica nessa área causa maior morbidade devido à anatomia topográfica entre essas estruturas e os linfonodos ali localizados. Dessa forma, essa área pouco explorada é objetivo desse estudo, que pretende comparar dados antropométricos e demográficos com a presença ou não de linfonodos. MÉTODOS: Estudo anatômico transversal, com dissecção de 32 cadáveres não formalizados do Serviço de Verificação de Óbitos da Capital, onde se dissecou a região cervical à direita até a exposição da região localizada entre o nervo laríngeo recorrente direito e as artérias carótida comum direita e tireóidea inferior direita, com subsequente ressecção em bloco do tecido fibrogorduroso dessa região para análise dos linfonodos após preparação específica para esse fim. RESULTADOS: As características demográficas da população estudada foram as seguintes: Idade(anos): 66,75 ± 13,89; Sexo: masculino 20/32 (62,5%) e feminino 12/32 (37,5%); Peso (Kg): 63,1 ± 12,36; Altura (metros): 1,66 ± 0,09; IMC (Kg/m2): abaixo do peso 5/32 (15,6%), normal: 20/32 (62,5%), obeso: 3/32 (9,4%), obesidade mórbida: 4/32 (12,5%); Raça: branca 21/32 (65,62%), negra 10/32 (31,25%), amarela 1/32 (3,12%); Dados antropométricos: brevilineo 8/32 (25%), normolíneo 15/32 (46,88%), longilíneo 9/32 (28,12%). A presença de linfonodos em 22/32 (68,75%), IC 95%, nos casos em que se encontraram linfonodos, a média foi de 1,65 ± 0,29 linfonodos por cadáver. Presença de linfonodos em cadáveres classificados como normolíneos, pelo teste exato de Fischer (p=0,03) e da raça branca, pelo teste exato de Fischer (p=0,04). Não se observou relação entre IMC e a presença de linfonodos, pelo teste de Sperman (p=0,461). CONCLUSÕES: A presença de linfonodos foi confirmada em 22/32 das espécimes estudadas (68,75%); Quanto às características dos linfonodos encontrados, o número variou de zero a 6 e, contando somente os casos em que os linfonodos foram achados, a média foi de 1,65 ± 0,29 linfonodos por cadáver. O tamanho variou de 0,9 a 5,39 mm no diâmetro transverso e de 1,36 a 11,64 mm no diâmetro longitudinal. Houve correlação antropométrica com presença de linfonodos nos cadáveres considerados normolíneos (p=0,03) e da raça branca (p=0,04) / INTRODUCTION: The papillary carcinoma of thyroid gland is the most prevalent endocrin malignant neoplasm, whose incidence is around 95%. This type of cancer causes increased likelihood of lymphatic spread in neck region, mainly to lymph nodes of the ipsilateral central compartiment, in level VI, such as the paratraqueal and the pretraqueal lymph nodes. However, there is a specific area, not described in the anatomic literature, that is receptor of metastasis and of tumor recurrences and is located among the right recurrent laryngeal nerve and the right common carotid and right inferior thyroid arteries. A surgical approach in this area causes more morbidity because of the topographic anatomy among those structures and the lymph nodes located there. Thus, this unexplored area is objective of this scientific study, which pretends to compare anthropometric and demographic data with the lymph nodes presence or absence. METHODS: Cross-sectional anatomic study, with dissection of 32 non-preserved corpses from the Serviço de Verificação de Óbitos da Capital, this study there had happened dissection of the right neck region until the exposition of the region located among the right recurrent laryngeal nerve and the right common carotid and right inferior thyroid arteries. Moreover, there was made resection in block of fibroadipose tissue of this region to analyse the lymph nodes after being prepared with specific material for this goal. RESULTS: Those are the demographic characteristics of this studied population: Age (in years): 66,75 ±13,89; Gender: male 20/32 (62,5%) and female 12/32 ( 37,5%); Weight(Kg): 63,1 ± 12,36; Height(meters): 1,66 ± 0,09; BMI (body mass index) (Kg/m2): underweight 5/32 (15,6%), normal: 20/32 (62,5%); obese: 3/32 (9,4%); morbid obesity: 4/32 (12,5%); Race: caucasian 21/32 (65,62%), afrodescendants 10/32(31,25%), asian 1/32 (3,12%); anthropometric data: brevilineo 8/32 (25%), normolineo 15/32 (46,88%), longilineo 9/32 (28,12%). There are lymph nodes in 22/32 (68,75%); Confidence Interval 95%, in the cases that lymph nodes were found, the average was 1,65 ± 0,29 lymph nodes for each corpse. There are lymph nodes in corpses classified as normolineos by accurate Ficher\'s Test(p= 0,03) and of the white race by accurate Ficher\'s Test(p=0,04). There is no observed correlation between BMI and lymph nodes found, by Spearman\'s correlation test( p=0,461). CONCLUSIONS: lymph nodes were found in 22/32 studied corpses (68,75%). 0 to 6 is the gap of the number of lymph nodes found in the same body. In those bodies which lymph nodes were found, the average is 1,65 ± 0,29 lymph nodes for each body. Their size varies from 0,9 to 5,39 mm in the transversal diameter and from 1,36 to 11,64 mm in the longitudinal diameter. There is a anthropometric correlation with lymph nodes presence in corpses considered as normolineos(p=0.03) and of the white race (p=0,04)

Objetivos: Descrever a incidência de lesões laríngeas agudas após extubação em unidade de terapia intensiva pediátrica (UTIP), e avaliar os seus fatores de risco e sua relação com a presença de estridor pós-extubação. Delineamento: Coorte Prospectiva. Métodos: Foram elegíveis todas as crianças de zero a cinco anos incompletos internadas na UTIP do Hospital de Clínicas de Porto Alegre que necessitaram de intubação endotraqueal por mais de 24 horas. Foram excluídas aquelas com história de intubação, patologia laríngea prévia, presença de traqueostomia atual ou no passado, presença de malformações craniofaciais e consideradas terminais pela equipe assistente. As crianças incluídas foram acompanhadas diariamente e, após a extubação, foram submetidas à fibronasolaringoscopia (FNL). Resultados: Foram acompanhadas 202 pacientes entre novembro de 2005 e dezembro de 2012. Na FNL após a extubação, 88 pacientes (43,6%) apresentaram lesões laríngeas agudas moderadas ou graves. Após análise multivariada dos fatores de risco, verificamos que tais lesões estão associadas com a presença de balonete no tubo endotraqueal (TET), risco relativo de 1,42 (IC 95%: 1,02-1,97; P=0,039). Dos pacientes com lesões moderadas a graves, 21 (23.9%) tiveram estridor por mais de 72 horas (P<0,001). Houve associação estatisticamente significativa entre a persistência de estridor após 72horas e a presença de balonete no TET (P=0,036). Conclusões: Este estudo encontrou uma alta frequência de lesões laríngeas agudas após a extubação, que foram associadas com o uso de TET com balonete. Além disso, o estridor persistente após 72 horas da extubação foi mais frequente em pacientes que apresentaram lesões laríngeas e naqueles que usaram TET com balonete. / Objectives: To describe acute laryngeal injuries after extubation in a pediatric intensive care unit (PICU) and to assess risk factors and their association with post-extubation stridor. Design: Prospective cohort. Methods: Children aged zero to five years admitted to the PICU of Hospital de Clínicas de Porto Alegre who required endotracheal intubation for more than 24 hours were eligible for study. Patients with previous intubation, history of laryngeal disease, current or past tracheostomy, presence of craniofacial malformations and those considered terminal by the staff were excluded from the study. Children were monitored daily and underwent flexible fiber-optic laryngoscopy (FFL) after extubation. Results: We followed 202 children between November 2005 and December 2012. In the FFL after extubation, 88 children (43,6%) had moderate to severe laryngeal lesions. After multivariate analysis of potential risk factors, it was found acute lesions were associated with the presence of cuffed endotracheal tube (ETT), relative risk of 1,42 (CI 95%: 1,02-1,97; P=0,039). Among patients with moderate to severe laryngeal lesions, 21 (23,9%) had stridor for more than 72 hours (P<0,001). There was a statistically significant association between persistent stridor after 72 hours and the presence of the cuffed ETT (P=0,036). Conclusions: This study found high frequency of acute laryngeal injuries after extubation, which were associated with cuffed ETT. Moreover, persistent stridor after 72 hours of extubation was more frequent in patients with laryngeal lesions and in those who used cuffed ETT.

INTRODUÇÃO: O grande desafio para o laringologista perante o quadro de paralisia unilateral do músculo cricotireoideo é fazer o diagnóstico do comprometimento desse músculo por meio da laringoscopia. Não existe consenso na literatura em relação aos achados vibratórios que possam servir como comprovação dessa condição. O objetivo desse estudo foi avaliar os efeitos da contração do músculo cricotireoideo sobre a vibração das pregas vocais usando a videolaringoscopia de alta velocidade e tentar encontrar um ou mais achados que pudessem ser utilizados como um sinal indicativo de paralisia unilateral do músculo cricotireoideo. MÉTODOS: Realizou-se um estudo experimental com 20 laringes excisadas de cadáveres humanos adultos masculinos. A vibração cordal foi produzida artificialmente com a passagem de ar comprimido através das pregas vocais. Cada laringe foi avaliada em três situações: contração bilateral do músculo cricotireoideo, contração unilateral do músculo cricotireoideo e ausência de contração de ambos os músculos cricotireoideos. Os seguintes parâmetros foram avaliados pela videolaringoscopia de alta velocidade: frequência fundamental, periodicidade da vibração, amplitude de vibração das pregas vocais e simetria de fase entre as pregas vocais. RESULTADOS: A diminuição da tensão longitudinal das pregas vocais decorrente da ausência de contração do músculo cricotireoideo unilateral e bilateral mostrou não alterar a periodicidade da vibração e a presença de assimetria de fase entre as pregas vocais, mas houve uma diminuição significativa da frequência fundamental (p < 0,001). Observou-se, também, um aumento da amplitude de vibração das pregas vocais direita e esquerda (p < 0,05), que apresentaram comportamento semelhante para esse parâmetro nas diferentes situações estudadas. CONCLUSÕES: A diminuição da tensão nas pregas vocais, causada pela ausência da contração do músculo cricotireoideo unilateral e bilateral, resultou em uma diminuição da frequência fundamental e em um aumento da amplitude de vibração. A presença de periodicidade em todas as laringes sugere que a videoestrobolaringoscopia, método usado mais frequentemente na prática clínica, possa ser um método adequado para avaliar pacientes com paralisia unilateral do músculo cricotireoideo. E, finalmente, os resultados sugerem que a paralisia unilateral do músculo cricotireoideo parece não ser capaz de produzir uma assimetria de tensão suficiente para induzir diferença de amplitude de vibração e de fase entre as pregas vocais e, desta forma, esses parâmetros não podem ser utilizados para fazer uma diferenciação segura dessa condição / INTRODUCTION: The great challenge for laryngologists dealing with cricothyroid muscle paralysis is to diagnose impaired cricothyroid muscle function using laryngoscopy. There is no consensus in the literature on the vibratory findings that can be used as a proof of this condition. The aim of this study was to evaluate the effects that cricothyroid muscle contraction has on vocal fold vibration as evaluated with high-speed videoendoscopy, and to identify one or more aspects of the vocal fold vibration that could be used as an indicator of unilateral cricothyroid muscle paralysis. METHODS: We conducted an experimental study on 20 larynges excised from adult male human cadavers. Laryngeal vibration was artificially produced by compressed air passing through the vocal folds. Each larynx was assessed in three situations: bilateral cricothyroid muscle contraction, unilateral cricothyroid muscle contraction and no contraction of either cricothyroid muscle. The following parameters were evaluated by high-speed videoendoscopy: fundamental frequency, periodicity, amplitude of vocal fold vibration, and phase symmetry between the vocal folds. RESULTS: Although neither unilateral nor bilateral cricothyroid muscle contraction altered periodicity of vibration or the occurrence of phase asymmetry, there was a significant decrease in fundamental frequency in parallel with the decreasing longitudinal tension (p < 0,001). We also found an increase in vibration amplitude of right and left vocal folds (p < 0,05), which were similar in terms of their behavior for this parameter in the various situations studied. CONCLUSION: Decreased vocal fold tension caused by the absence of unilateral or bilateral contraction of cricothyroid muscle resulted in a decrease in fundamental frequency and an increase in vibration amplitude. The presence of regular periodicity in all studied larynges suggests that videostroboscopy, method most frequently used in clinical practice, may be a suitable method for the evaluation of patients with unilateral cricothyroid muscle paralysis. We also believe that unilateral cricothyroid muscle paralysis is not capable of causing a sufficient degree of tension asymmetry to induce phase asymmetry or a difference in vibration amplitude between the vocal folds and, hence, these parameters can\'t be used as reliable indicators of this condition

Der Einsatz von Ex-vivo-Modellen ermöglicht die experimentelle Untersuchung isolierter Organe, die vom Gesamtorganismus unbeeinflusst sind. Für viele Spezies und Organe sind solche Modelle bereits beschrieben. Wird das Organ dabei perfundiert, stehen flusskonstante und druckkonstante Perfusion zur Auswahl. Für den Larynx des Pferdes existiert in der Literatur bisher nur ein einziges flusskonstant perfundiertes Modell. Im Bereich der Pferdemedizin können solche Modelle helfen, neue Behandlungsoptionen der sogenannten recurrent laryngeal neuropathy (RLN) zu entwickeln, bei der es zu einer Atrophie des Musculus cricoarytaenoideus dorsalis (CAD) kommt. Die Studie hatte zum Ziel, ein druckkonstant perfundiertes Ex-vivo-Modell des equinen Larynx zu etablieren, in dessen Fokus insbesondere die Funktionalität des CAD stand. Hierzu wurden in zwei Vorversuchsphasen verschiedene Parameter auf ihre Eignung als Marker für die Vitalität des entnommenen Kehlkopfes getestet. Die ermittelten Parameter wurden dann in den Hauptversuchen verwendet, um die Vitalität des perfundierten Kehlkopfes zu Beginn und am Ende der Perfusion zu untersuchen. Für die Untersuchungen wurden Kehlköpfe von 16 Pferden verwendet. Diese wurden im direkten Anschluss an die Euthanasie frisch entnommen und im Labor an einen Perfusionskreislauf angeschlossen. Hierzu wurde eine modifizierte Tyrode-Lösung beidseits über die Arteria thyroidea cranialis perfundiert. Die Lösung wurde über den gesamten Versuchszeitraum mit Carbogen begast und somit ein pH-Wert von 7,35 bis 7,45 gehalten. Es wurde ein konstanter Perfusionsdruck von 9,81 kPA eingestellt. Im Anschluss an die Adaptationsphase wurden die Vitalitätsparameter zur Überprüfung der Unversehrtheit und Funktionalität der arteriellen Gefäßversorgung und des CAD getestet. Neben der myogenen Autoregulation wurde die Reaktion der Gefäße auf die Zugabe von Noradrenalin (NA), Nitroprussid (NO) und Papaverin (Papa) als Vasokonstriktor (NA) und Vasodilatatoren (NO, Papa) ermittelt. Des Weiteren wurde die Kontraktilität und Funktionalität des CAD durch Messung des intramuskulären Druckes nach elektrischer Stimulation überprüft. Zusätzlich wurden aus dem Perfusat Proben zur Messung von Laktat und der Aktivität der Laktat-Dehydrogenase (LDH) zu drei Zeitpunkten entnommen. Für die statistische Auswertung wurden eine einfache ANOVA mit wiederholten Messungen sowie der Holm-Sidak-Test als Post-hoc-Test im Falle signifikanter Unterschiede verwendet. Dabei wurde eine Wahrscheinlichkeit von p < 0,05 als statistisch signifikant angenommen. Im Hauptversuch konnten an n = 5 Kehlköpfen Perfusionen über einen Zeitraum von 352 ± 18,59 Minuten durchgeführt werden. Die myogene Autoregulation zu Beginn der Perfusion war bei drei Kehlköpfen und zum Ende der Perfusion bei vier Kehlköpfen sichtbar. Auf die Zugabe von NA reagierten am Beginn der Perfusion vier Kehlköpfe und am Ende der Perfusion alle fünf Kehlköpfe mit einer Vasokonstriktion. NO erzeugte am Versuchsbeginn bei vier Kehlköpfen eine Vasodilatation. Die Zugabe von NO und Papa führte am Versuchsende in allen Fällen zu einer Vasodilatation. Die Kontraktilität des CAD nach elektrischer Stimulation konnte in allen Fällen am Versuchsbeginn und Versuchsende gemessen werden. Bei Überprüfung der Funktionalität des CAD zeigten sich insgesamt heterogene Messergebnisse. Im Verlauf der Perfusion stiegen sowohl die Konzentration des Laktats als auch die Aktivität der LDH statistisch signifikant an, lagen aber beide im Bereich der für das Pferd in der Literatur beschriebenen Normwerte. Die vorliegende Arbeit beschreibt erstmalig die Etablierung eines druckkonstant perfundierten Ex-vivo-Modells des equinen Larynx. Über verschiedene Vitalitätstests wurde die Intaktheit und Funktionalität des perfundierten Kehlkopfes überprüft. Die myogene Autoregulation hat sich als sinnvoller aber störanfälliger Test erwiesen. Die Applikation vasoaktiver Substanzen zur Überprüfung der Funktionalität der arteriellen Gefäße hat sich als sehr zuverlässig gezeigt. Der Test auf Kontraktilität des CAD hat sich als Vitalitätsparameter mit geringer Aussagekraft gezeigt. Der Test auf Funktionalität des CAD hingegen hatte eine höhere Aussagekraft über die Vitalität des entnommenen Kehlkopfes, zeigte aber auch interindividuelle Schwankungen. Das in der vorliegenden Arbeit beschriebene Ex-vivo-Modell stellt eine solide Grundlage für weitere Untersuchungen auf dem Gebiet der Kehlkopflähmung dar.

Treatment decision-making in head and neck oncology is gaining complexity by the increasing evidence pointing towards more individualized and selective treatment options. Therefore, decision making in multidisciplinary teams is becoming the key point in the clinical pathways. Clinical decision-support systems based on Bayesian networks can support complex decision-making processes by providing mathematically correct and transparent advises. In the last three decades, different clinical applications of Bayesian networks have been proposed. Because appropriate data for model learning and testing is often unobtainable, expert modeling is required. To decrease the modeling and validation effort, networks usually represent small or highly simplified decision structures. However, especially systems for supporting multidisciplinary treatment decisions may only gain a user’s confidence if the systems’ results are comprehensive and comprehensible. Challenges in developing such systems relate to knowledge engineering, model validation, system interaction, clinical implementation and standardization. These challenges are well-known, however, they are not or only partially addressed by the developers. The thesis presented a methodology for the development of Bayesian network-based clinical treatment decision support systems. For this purpose, a concept introduced interactions between actors and systems. The proposed concept emphasizes model development with an exemplary use case of model interaction. A graph model design was presented that allows integrating all relevant variables of multidisciplinary treatment decisions. At the current stage, we developed TreLynCa: A graph model representing the treatment decisions of laryngeal cancer. From TreLynCa, a subnetwork that represents the TNM staging is completed by the required probabilistic parameters, and finally validated. The model validation required the development of a validation cycle in combination with existing data- and expert-based validation methods. Furthermore, modeling methods were developed that enable domain experts to model autonomously without Bayesian network expertise. Specifically, a novel graph modeling method was developed, and an existing method for modeling probabilistic parameters was extended. Both methods transform Bayesian network modeling tasks into a natural language form and provide a regulated modeling environment. A method for graph modeling is based on the presented graph model design with a regulated and restricted modeling procedure. This modeling procedure is supposed to enable collaborative modeling of compatible models. The method is currently under development. A method for probabilistic modeling is extended to reduce the modeling effort to a linear time. The method has been implemented as a web tool and was tested and evaluated in two studies. Finally, for clinical application of the TNM model, requirements were collected and constructed in a visual framework. In collaboration with visual scientists, the framework has been implemented and evaluated.

No description available.

Larynxcancer är den tredje vanligaste formen av huvud- och halscancer och drabbar cirka 175 personer årligen i Sverige. En vanlig behandlingsmetod vid larynxcancer är strålbehandling. Detta är en retrospektiv journalstudie med syfte att undersöka hur svälj- och röstfunktion samt nutritionsstatus påverkas av strålbehandling för larynxcancer. Studiens syfte är även att undersöka om det finns något samband mellan tumörgrad och sväljförmåga efter avslutad behandling samt om och när svälj- och röstfunktion återhämtas. Studien har även undersökt andelen patienter som erbjudits logopedkontakt. I studien har 52 patienter med larynxcancer (C.32) inom region Gävleborg inkluderats. Resultaten indikerar att strålbehandling påverkar svälj- och röstfunktion samt nutritionsstatus. Vid strålavslut hade 24 av 48 patienter tecken på sväljsvårigheter och 33 av 52 patienter hade en påverkan på röstfunktionen. Under behandlingen noterades ett ökat behov av näringsdryck och 24 av 37 deltagare gick ner i vikt under eller efter behandling vilket indikerar nutritionssvårigheter. Andelen patienter som var i behov av enteral nutrition vid strålavslut var 7 av 52 patienter. Sammanlagt erbjöds 33 av 52 patienter logopedkontakt. Återhämtning av sväljfunktionen rapporterades hos 22 av 39 patienter inom ett år efter avslutad strålbehandling. Återhämtning av röstfunktionen noterades hos 8 av 40 patienter inom fem år efter avslutad strålbehandling. Studiens resultat ger värdefull information om strålbehandlingens påverkan på livsviktiga funktioner och hoppas kunna bidra med underlag till prospektiva studier inom huvud- och halscancer. / Laryngeal cancer is the third most common form of head- and neck cancer and each year approximately 175 people receive the diagnosis in Sweden. Radiotherapy is a common treatment against laryngeal cancer. This is a retrospective cohort study, and it has investigated how swallowing, voice function and nutritional status can be affected by radiotherapy. The aim of the study was to explore whether there is a correlation between the grade of tumor and swallowing after treatment and when swallowing and voice function recover. The aim was also to research how many patients received contact with a speech- and language pathologist before or during treatment. The following study included 52 patients with laryngeal cancer (C.32) within the region of Gävleborg, Sweden. The results indicate that radiotherapy affects swallowing, voice function, and nutritional status. By the end of treatment, 24 of 48 patients had signs of dysphagia and voice function was affected in 33 of 52 patients. An increase in the need for nutritional drinks was noted throughout radiotherapy and 24 of 37 patients lost weight during or after treatment, which indicates nutritional difficulties. At the end of the treatment, 7 of 52 patients needed enteral nutrition. In total, 33 of 52 patients were offered contact with a speech- and language pathologist. Recovery of the swallowing function was reported in 22 of 39 patients at some point during the first year after radiotherapy. Recovery of voice function was reported in 8 of 40 patients at some point during five years after radiotherapy. The results of the study indicates possible implications that radiotherapy might have on vital functions, and it can suffice as a basis for further prospective studies within the area of head- and neck cancer.

The increase in diagnostic and therapeutic procedures in the treatment of oncological diseases, as well as the limited capacity of experts to provide information, necessitates the development of therapy decision support systems (TDSS). We have developed a treatment decision model that integrates available patient information as well as tumor characteristics. They are assessed according to their relevance in evaluating the optimal therapy option. Our treatment model is based on Bayesian networks (BN) which integrate patient-specific data with expert-based implemented causalities to suggest the optimal therapy option and therefore potentially support the decision-making process for treatment of laryngeal carcinoma. To test the reliability of our model, we compared the calculations of our model with the documented therapy from our data set, which contained information on 97 patients with laryngeal carcinoma. Information on 92 patients was used in our analyses and the model suggested the correct treatment in 419 out of 460 treatment modalities (accuracy of 91%). However, unequally distributed clinical data in the test sets revealed weak spots in the model that require revision for future utilization.

The periodic repetitions of laryngeal adduction and abduction gestures were uttered by 16 subjects. The movement of the cuneiform tubercles was tracked over time in the laryngoscopic recordings of these utterances. The adduction velocity and abduction velocity were determined objectively by means of a piecewise linear model fitted to the cuneiform tubercle trajectories. The abduction was found to be significantly faster than the adduction. This was interpreted in terms of the biomechanics and active control by the nervous system. The biomechanical properties could be responsible for a velocity of abduction that is up to 51% higher compared to the velocity of adduction. Additionally, the adduction velocity may be actively limited to prevent an overshoot of the intended adduction degree when the vocal folds are approximated to initiate phonation.

Introduktion: Att skapa fri luftväg i samband med prehospitalt hjärtstopp är en komplicerad åtgärd i en stressande situation. Det finns flera metoder för denna åtgärd och de har olika svårighetsgrad beroende på vilken metod som ambulanssjuksköterskan behöver använda för att nå framgång. Denna åtgärd förväntas ambulanssjuksköterskan klara av trots att miljön är utmanande och tidspressen stor.   Syfte: Att beskriva ambulanssjuksköterskors upplevelser av etablering av fri luftväg i samband med hjärtstopp.   Metod: Kvalitativ intervjustudie som analyseras med latent innehållsanalys. Tolv semistrukturerade intervjuer genomfördes på tre verksamhetsställen i södra Sverige.   Resultat: Ambulanssjuksköterskorna berättade om hur luftvägshantering är en liten men viktig del av allt de ska klara av i sin yrkesroll. Det finns en otrygghet i momentet intubation som beror på bristande utbildning i kombination med hur sällan ambulanssjuksköterskan gör detta i det dagliga arbetet. Studien resulterade i tre huvudkategorier: Otrygghet i yrkesrollen, Prehospitala framgångsfaktorer och Personcentrerad vård genom samarbete med tillhörande tolv subkategorier. Det som bekymrade ambulanssjuksköterskorna mest var luftvägshantering på barn. Det som upplevs vara den största framgångsfaktorn betonades vara de enkla åtgärderna när det gäller luftvägshantering.   Slutsats: För att öka ambulanssjuksköterskans trygghet i luftvägshantering krävs ökade utbildningsinsatser. Arbetsgivaren bör ta ett ökat ansvar för utbildning genom att skapa förutsättningar och uppföljning. Vidare bör de riktlinjer som finns för luftvägshantering ses över. De enklaste metoderna är oftast de bästa prehospitalt. / Introduction: To manage an airway in a prehospital environment is a complex measure in a stressful situation. There are several methods for this measure and they have various level of severity depending on the method the ambulance nurse chooses to apply. This measure is expected to be managed by the ambulance nurse despite rough environment and lack of time.   Purpose: To describe the ambulance nurse’s experiences of airway management in a cardiac arrest situation.   Method:  Twelve semi-structured qualitative interviews was made and analyzed by content analysis. The interviews were made at three different ambulance organizations in the south of Sweden     Result: The ambulance nurses told about how small but essential task airway management is. But it’s still a task they must be able to perform in their work.  There is an insecurity in the moment of intubation which is related to lack of training and how rarely they perform the moment in their daily duties. The study resulted in three main categories: Insecurity in the profession, Prehospital success factors and Person-centered care through teamwork with twelve subcategories. What concerned the ambulance nurses the most was airway management on children. They describe the greatest success factor to be the simplest possible measures when it comes to airway management.   Conclusion: To increase the ambulance nurse’s security in airway management more education efforts is needed. Employers should take a greater responsibility for education by creating conditions and monitoring. Therefore, should the guidelines for airway management be reviewed. The simplest methods in airway management are often the most successful.