Speech Production During Mechanical Ventilation in Tracheostomized Individuals

1994 ◽  
Vol 37 (1) ◽  
pp. 53-63 ◽  
Author(s):  
Jeannette D. Hoit ◽  
Steven A. Shea ◽  
Robert B. Banzett

This investigation provides the first detailed description of speech production during mechanical ventilation. Seven adults with tracheostomies served as subjects. Recordings were made of chest wall motions, neck muscle activity, tracheal pressure, air flow at the nose and mouth, estimated blood-gas levels, and the acoustic speech signal during performance of a variety of speech tasks. Results indicated that subjects spoke for short durations that spanned all phases of the ventilator cycle, altered laryngeal opposing pressures in response to the continually changing tracheal pressure wave, and expended relatively small volumes of gas for speech production. Speech was improved by making selected ventilator adjustments. Suggestions for clinical interventions are offered.

Author(s):  
Carol A. Fowler

A theory of speech production provides an account of the means by which a planned sequence of language forms is implemented as vocal tract activity that gives rise to an audible, intelligible acoustic speech signal. Such an account must address several issues. Two central issues are considered in this article. One issue concerns the nature of language forms that ostensibly compose plans for utterances. Because of their role in making linguistic messages public, a straightforward idea is that language forms are themselves the public behaviors in which members of a language community engage when talking. By most accounts, however, the relation of phonological segments to actions of the vocal tract is not one of identity. Rather, phonological segments are mental categories with featural attributes. Another issue concerns what, at various levels of description, the talker aims to achieve. This article focuses on speech production, and considers language forms and plans for speaking, along with speakers' goals as acoustic targets or vocal tract gestures, the DIVA theory of speech production, the task dynamic model, coarticulation, and prosody.


2011 ◽  
Vol 21 (2) ◽  
pp. 44-54
Author(s):  
Kerry Callahan Mandulak

Spectral moment analysis (SMA) is an acoustic analysis tool that shows promise for enhancing our understanding of normal and disordered speech production. It can augment auditory-perceptual analysis used to investigate differences across speakers and groups and can provide unique information regarding specific aspects of the speech signal. The purpose of this paper is to illustrate the utility of SMA as a clinical measure for both clinical speech production assessment and research applications documenting speech outcome measurements. Although acoustic analysis has become more readily available and accessible, clinicians need training with, and exposure to, acoustic analysis methods in order to integrate them into traditional methods used to assess speech production.


Author(s):  
Jeanne-Marie Krischer ◽  
Karolin Albert ◽  
Alexander Pfaffenroth ◽  
Elena Lopez-Rodriguez ◽  
Clemens Ruppert ◽  
...  

AbstractMechanical ventilation triggers the manifestation of lung injury and pre-injured lungs are more susceptible. Ventilation-induced abnormalities of alveolar surfactant are involved in injury progression. The effects of mechanical ventilation on the surfactant system might be different in healthy compared to pre-injured lungs. In the present study, we investigated the effects of different positive end-expiratory pressure (PEEP) ventilations on the structure of the blood–gas barrier, the ultrastructure of alveolar epithelial type II (AE2) cells and the intracellular surfactant pool (= lamellar bodies, LB). Rats were randomized into bleomycin-pre-injured or healthy control groups. One day later, rats were either not ventilated, or ventilated with PEEP = 1 or 5 cmH2O and a tidal volume of 10 ml/kg bodyweight for 3 h. Left lungs were subjected to design-based stereology, right lungs to measurements of surfactant proteins (SP−) B and C expression. In pre-injured lungs without ventilation, the expression of SP-C was reduced by bleomycin; while, there were fewer and larger LB compared to healthy lungs. PEEP = 1 cmH2O ventilation of bleomycin-injured lungs was linked with the thickest blood–gas barrier due to increased septal interstitial volumes. In healthy lungs, increasing PEEP levels reduced mean AE2 cell size and volume of LB per AE2 cell; while in pre-injured lungs, volumes of AE2 cells and LB per cell remained stable across PEEPs. Instead, in pre-injured lungs, increasing PEEP levels increased the number and decreased the mean size of LB. In conclusion, mechanical ventilation-induced alterations in LB ultrastructure differ between healthy and pre-injured lungs. PEEP = 1 cmH2O but not PEEP = 5 cmH2O ventilation aggravated septal interstitial abnormalities after bleomycin challenge.


1983 ◽  
Vol 55 (5) ◽  
pp. 1614-1622 ◽  
Author(s):  
J. F. Ledlie ◽  
A. I. Pack ◽  
A. P. Fishman

We examined the effects of progressive hypercapnia and hypoxia on the efferent neural activity in a whole abdominal expiratory nerve (medial branch of the cranial iliohypogastric nerve (L1) in anesthetized, paralyzed dogs. To eliminate effects of phasic lung and chest-wall movements on expiratory activity, studies were performed in the absence of breathing movements. Progressive hyperoxic hypercapnia and isocapnic hypoxia were produced in the paralyzed animals by allowing 3-5 min of apnea to follow mechanical ventilation with 100% O2 or 35% O2 in N2, respectively; during hypoxia, isocapnia was maintained by intravenous infusion of tris(hydroxymethyl)aminomethane buffer at a predetermined rate. To quantify abdominal expiratory activity, mean abdominal nerve activity in a nerve burst was computed by integrating the abdominal neurogram and dividing by the duration of the nerve burst. Hypercapnia and hypoxia both increased mean abdominal nerve activity and decreased expiratory duration. In contrast to the ramplike phrenic neurogram, the abdominal neurogram consisted of three phases: an initial rising phase, a plateau phase in which abdominal nerve activity was approximately constant, and a terminal declining phase in which the activity returned to the base-line level. The height of this plateau phase and the rates of rise and decline of abdominal nerve activity all increased with increasing hypercapnia and hypoxia. We conclude that, with proprioceptive inputs constant, both hypercapnia and hypoxia are excitatory to abdominal expiratory neural activity.


1976 ◽  
Vol 41 (1) ◽  
pp. 23-39 ◽  
Author(s):  
Frank Parker

Distinctive feature is not a unique concept within linguistic theory. It has two distinct theoretical bases: phonemic theory and generative theory. Phonemic theory assumes a direct correspondence between distinctive features (the elements of phonemes) and the speech signal. Although this assumption can be shown to be incorrect, it seems to be the one most widely held in speech science. Generative theory, on the other hand, assumes no such direct relation and consequently can account for certain linguistic phenomena that phonemic theory cannot. This theory then seems to be preferable to phonemic theory for a featural analysis of misarticulation. However, there is a problem. Chomsky and Halle’s system (generative theory) as it stands does not deal with the link between what it conceives to be the lowest level of linguistic structure (the phonetic matrix) and speech production. Therefore, Chomsky and Halle’s distinctive features cannot be applied fruitfully to all instances of misarticulation. The discrepancy that exists between phonological structure and the speech signal must be accounted for in a theory of speech production. This can be accomplished by recognizing a production matrix below the phonetic matrix, where segments are described in terms of production features. The crucial point is that no one-to-one relationship necessarily exists between distinctive features and production features.


1991 ◽  
Vol 34 (4) ◽  
pp. 761-767 ◽  
Author(s):  
Elaine T. Stathopoulos ◽  
Jeannette D. Hoit ◽  
Thomas J. Hixon ◽  
Peter J. Watson ◽  
Nancy Pearl Solomon

Established procedures for making chest wall kinematic observations (Hoit & Hixon, 1987) and pressure-flow observations (Smitheran & Hixon, 1981) were used to study respiratory and laryngeal function during whispering and speaking in 10 healthy young adults. Results indicate that whispering involves generally lower lung volumes, lower tracheal pressures, higher translaryngeal flows, lower laryngeal airway resistances, and fewer syllables per breath group when compared to speaking. The use of lower lung volumes during whispering than speaking may reflect a means of achieving different tracheal pressure targets. Reductions in the number of syllables produced per breath group may be an adjustment to the high rate of air expenditure accompanying whispering compared to speaking. Performance of the normal subjects studied in this investigation does not resemble that of individuals with speech and voice disorders characterized by low resistive loads.


2016 ◽  
Vol 147 ◽  
pp. 613-617
Author(s):  
Gerrit Thiele ◽  
Patricia Kafka ◽  
Stefan Litzenberger ◽  
Anton Sabo
Keyword(s):  

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