Objective measures of dysphagia complexity in children related to suckle feeding histories, gestational ages, and classification of their cerebral palsy.

Data collected during the routine assessment of 117 dysphagic children with cerebral palsy have been related to both suckle feeding histories and gestational ages and to the classification of cerebral palsy. In addition, a concurrent survey involving 281 children with cerebral palsy in special schools was undertaken which revealed that the sample of referred children appeared to be a true representation of a wider population of dysphagic children with cerebral palsy. A Feeding Difficulty Symptom Score (FDSS) describes the severity of swallowing symptoms reported. A numerical Dysphagia Complexity Index (DCI) quantifies numerically the neurological complexity of the swallowing difficulty. The FDSS correlates closely with the DCI. Twenty-seven percent of mothers of the children who were referred for advice on their present swallowing difficulties stated that they recalled no suckle feeding problems. However, there was no difference in the severity of present swallowing difficulties between those infants who suckle fed well and those who experienced severe difficulties. Those referred children with cerebral palsy born at term exhibited more complex later swallowing problems and were more likely to be classified as athetoid than those born preterm.

Non-invasive technique for assessment and management planning of oral-pharyngeal dysphagia in children with cerebral palsy.

The non-invasive Exeter Dysphagia Assessment Technique (EDAT) was evaluated as a method of assessing the aetiology of dysphagia in children with cerebral palsy (CP). Data were collected from a group of 20 typically developing children (nine girls, 11 boys; age range 7 to 14 years) for comparison with 125 dysphagic children with CP (81 boys, 44 girls; age range 1 to 18 years). The swallowing mechanism has been separated into physiological phases: anticipatory, delivery, oral transit, and oral-pharyngeal. Normal or abnormal function in each phase was recorded and the common causes of any impaired phase were considered, starting with generalized possibilities before focusing on specific parts of swallowing physiology. Data from 125 dysphagic children with CP show marked differences from the data for the typically developing children. Interpreting individual results was valuable in assisting the assessment team to formulate management strategies; two examples are presented. The technique appears to provide a cost-effective, non-invasive, and valuable clinical tool.

Deglutition apnoea as indicator of maturation of suckle feeding in bottle-fed preterm infants.

The maturation of deglutition apnoea time was investigated in 42 bottle-fed preterm infants, 28 to 37 weeks gestation, and in 29 normal term infants as a comparison group. Deglutition apnoea times reduced as infants matured, as did the number and length of episodes of multiple-swallow deglutition apnoea. The maturation appears related to developmental age (gestation) rather than feeding experience (postnatal age). Prolonged (> 4 seconds) episodes of deglutition apnoea remained significantly more frequent in preterm infants reaching term postconceptual age compared to term infants. However, multiple-swallow deglutition apnoeas also occurred in the term comparison group, showing that maturation of this aspect is not complete at term gestation. The establishment of normal data for maturation should be valuable in assessing infants with feeding difficulties as well as for evaluation of neurological maturity and functioning of ventilatory control during feeding.

Comparative review of techniques for recording respiratory events at rest and during deglutition.

The coordination between swallowing and respiration is essential for safe feeding, and noninvasive feeding-respiratory instrumentation has been used in feeding and dysphagia assessment. Sometimes there are differences of interpretation of the data produced by the various respiratory monitoring techniques, some of which may be inappropriate for observing the rapid respiratory events associated with deglutition. Following a review of each of the main techniques employed for recording resting, pre-feeding, feeding, and post-feeding respiration on different subject groups (infants, children, and adults), a critical comparison of the methods is illustrated by simultaneous recordings from various respiratory transducers. As a result, a minimal combination of instruments is recommended which can provide the necessary respiratory information for routine feeding assessments in a clinical environment.

Dysphagia following strokes: clinical observations of swallowing rehabilitation employing palatal training appliances.

A retrospective study was undertaken to evaluate the progress of a group of dysphagic stroke patients for whom a dental prosthesis the Palatal Training Appliance (PTA), was used in the active rehabilitation of the swallowing mechanism. Patients selected were those who had sustained a stroke uncomplicated by other neurological illness, during one 12-month period, and whose dysphagia caused anxiety to the medical staff in the hospital ward. Thirty severely dysphagic stroke patients satisfied these criteria. The study recorded the duration and type of supplementary feeding required during hospitalization. Thirteen patients had evidence of aspiration before the PTA was fitted and 5 afterwards. Seven patients died, but only 1 was recorded as having a febrile illness which may have contributed to the death. At discharge, which averaged 10 weeks after admission, 22 of the 23 survivors were taking an adequate oral diet. It was also noted that almost half of the patients who wore dentures before the cerebrovascular event were unable to control them afterwards, adding to their neurological swallowing difficulties. The fitting of a PTA and correction of unstable dentures appeared to help both motivation and function. The results show an improvement in the rehabilitation of oral feeding compared with previous reports by other authors, who did not use the dental appliance. There did not appear to be any medical contraindication to its use.

Superimposition of analogue data onto a video image: a new technique.

There are many tools to aid the clinician in making an accurate medical diagnosis including various imaging techniques and recording analogue signals from the patient. A new, inexpensive method of combining a video image and the instantaneous values of analogue waveforms is described here. The system, TVDATA, is reliable, compact and portable and has been successfully used in various clinical situations. The unit requires a standard video source, such as a camera, a TV monitor, a video recorder and the output from the analogue source or sources. The analogue data are converted into a digital signal and then displayed in a convenient part of the screen as a horizontal bar. Two types of data channel are available--uni- and bidirectional. A number of these channels can be used to record different analogue parameters and an inbuilt octal frame counter assists subsequent review of the video record.

The synchronization of respiration and swallow sounds with videofluoroscopy during swallowing.

Simultaneous recording of adult subjects sipping small amounts of fluid from a cup have been obtained by videofluoroscopy together with feeding respiratory patterns and swallow sounds from the Exeter Dysphagia Assessment Technique (EDAT). These allowed visual representations of respiration and swallow sounds to be superimposed on a videofluoroscopy recording using a split-screen technique. Sequentially numbered, 1/50 sec, half-frame photographic prints were examined and schematic drawings of the relevant radiographs were made. These were superimposed on to the actual EDAT printed chart of the same swallow event, their exact time relationship with respiration and cervical swallow sounds being preserved. The results allow events in the barium videofluoroscopy to be related to events in the feeding respiratory pattern and swallow sounds recorded by EDAT.

Dysphagia in cerebral palsy: a comparative study of the Exeter Dysphagia Assessment Technique and a multidisciplinary assessment.

Eighteen children with cerebral palsy in a special school, most of whom had feeding difficulties, were studied to compare the diagnostic value of the Exeter Dysphagia Assessment Technique (EDAT) with an exhaustive clinical assessment undertaken by a multidisciplinary team experienced in the diagnosis and treatment of dysphagia of neurological origin. Four feeding skills were assessed by each method independently, viz. anticipation, intraoral sensory perception, oral-motor efficiency, and pharyngeal triggering. Comparison of the two sets of results showed agreement in at least 78% of the assessed skills. The possible reasons for the few discrepancies are discussed. The noninvasive EDAT equipment was easy to use with the children, who had a range of type and severity of cerebral palsy. The test was undertaken in their familiar surroundings and took 15 to 20 min per child. Interpretation of the results showed that EDAT provided a rapid, reliable diagnostic aid which assisted in the assessment of the degree of feeding impairment within each of the four feeding skills tested.

Coordination of sucking, swallowing and breathing in the newborn: its relationship to infant feeding and normal development.

Non-invasive, sensitive equipment was designed to record nasal air flow, the timing and volume of milk flow, intraoral pressure and swallowing in normal full-term newborn babies artificially fed under strictly controlled conditions. Synchronous recordings of these events are presented in chart form. Interpretation of the charts, with the aid of applied anatomy, suggests an hypothesis of the probable sequence of events during an ideal feeding cycle under the test conditions. This emphasises the importance of complete coordination between breathing, sucking and swallowing. The feeding respiratory pattern and its relationship to the other events was different from the non-nutritive respiratory pattern. The complexity of the coordinated patterns, the small bolus size which influenced the respiratory pattern, together with the coordination of all these events when milk was present in the mouth, emphasise the importance of the sensory mechanisms. The discussion considers (1) the relationship between these results, those reported by other workers under other feeding conditions and the author's (WGS) clinical experience, (2) factors which appear to be essential to permit conventional bottle feeding and (3) the importance of the coordination between the muscles of articulation, by which babies obtain their nourishment in relation to normal development and maturation.

The relationship between peak expiratory sound intensity and peak expiratory flow rate in the thoroughbred horse during exercise.

Peak expiratory sound intensity (dB SPL), obtained by means of a radiostethoscope, and peak expiratory flow rate, obtained using a mask incorporating a thermistor flow sensor, were measured in six Thoroughbreds over a range of stride rates from 100 to 140 strides per min. The results show linear relationships between peak dB SPL and stride rate, peak expiratory flow rate and stride rate and also between peak expiratory flow rate and peak dB SPL. Peak expiratory dB SPL can therefore indicate peak expiratory flow rate.

Impedance plethysmography.

The technique of impedance plethysmography is described and its application to observation of lung volume changes in the horse at exercise is discussed. The results from horse at rest show that there is a close relationship between rate of lung volume change (flow rate) and the associated impedance changes during both inspiration and expiration. Impedance changes during exercise were related to inspiration and expiration by observation of associated respiratory sounds. Artefacts related to technical difficulties are also indicated.

The Exeter Dysphagia Assessment Technique.

The Exeter Dysphagia Assessment Technique (EDAT) uses noninvasive equipment to record, simultaneously, "feeding respiratory patterns," the time drink entered the mouth, and associated swallow sounds during feeding. The easily portable equipment enabled patients' swallowing ability to be tested, at the bedside if necessary, using a small amount of fruit-flavored drink. The results appear in chart form. EDAT findings from groups of normal subjects aged 2-90 years were compared with those from patients with dysphagia of neurologic origin and normal subjects under experimental feeding conditions. The results revealed maturation of the feeding respiratory pattern in the teenage years and remarkable consistency thereafter. Differences in the recordings between the normal and abnormal subjects were sufficiently marked to allow the findings to be used in the diagnosis of other patients with dysphagia of doubtful neurologic cause. Interpretation of the charts and recorded timings of the oral and pharyngeal stages of swallowing permitted a more accurate identification of sensory nerve, motor nerve, and functional involvement causing dysphagia of neurologic origin and may be used as a guide to the origin of the sensory deficit.

Respiratory patterns associated with swallowing: Part 1. The normal adult pattern and changes with age.

Simple, non-invasive equipment was designed to record respiratory patterns associated with swallowing food or drink in young and elderly healthy adults, to compare with neurologically impaired patients who complained of dysphagia. The timing of the entry of the test drink from a spoon into the mouth, the swallow event and respiration were recorded electronically and were presented in chart form. The equipment proved to be easy to use and the results were consistent. All 33 subjects showed a well-defined respiratory pattern, with individual minor variations, but different from the pattern of their resting respiration. The direction of respiration during spoon contact was consistent for each individual and the pharyngeal stage of swallowing was almost always followed by a large expiration. Thus the resting respiration is not simply arrested during swallowing, but is substituted by a different, well-controlled pattern.

Respiratory patterns associated with swallowing: Part 2. Neurologically impaired dysphagic patients.

The co-ordination of respiration and swallowing was recorded electronically in three groups of patients who complained of dysphagia following a stroke, or associated with multiple sclerosis or motor neurone disease. The test used was simple and the equipment easily taken to the patient, in bed if necessary. All the patients showed differences from normal subjects and there were differences between each of the neurologically impaired groups. The technique appears to allow an assessment of the state of oropharyngeal motor and sensory functions separately during swallowing.

The effect of tongue position on division of airflow in the presence of velopharyngeal defects.

Results of studies of nasal to oral airflow ratios are reported using simple and accurate anatomical models to record the effect of differing positions of lips, tongue and soft palate, with particular reference to the effect of the position of the dorsum of the tongue and various sizes of velopharyngeal defect. The resistances to airflow produced by the labial, palatolingual, velopharyngeal and naral valves were found to be interdependent. Variations in tongue position alone could allow the same nasal airflow during a more than three-fold variation in the size of velopharyngeal defects. The degree of nasal escape of air which is responsible for the typical "cleft palate" type of speech cannot be assessed by observation of the size of the velopharyngeal defect alone.