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Rheological Aspects of Swallowing and Dysphagia 499
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800
600
400
(Pa)
σ
200
0
0 200 400 600 800 1000 1200
Time (s)
Fig. 5 Transient shear flow tests at different constant shear
rates for a selected pudding formulation
-1
0.01 s
-1
0.1 s
-1
1 s
-1
10 s
-1
50 s
-1
100 s
Figoni's model
flow indexes. With the use of the third parameter,
this model provides a somewhat better fit to some
experimental data, being particularly recommended
to describe the material flow behavior in the highshear-rate region.
2.3.1.3 Carreau’s Model
On the basis of molecular network considerations,
Carreau (1972) proposed the following viscosity
model, which incorporates both low-shear-rate-limiting andhigh-shear-rate-limiting viscosities, g
g g
1
go g
¼
1
The parameter k ¼ 1=_c
1
: ð33Þ
½1 þðk_cÞ
c
2s
; where_ccis a critical
and g?:
o
shear rate for the onset of the shear-thinning region.
On the other hand, s is a parameter related to the slope
of the power-law region. This model can describe the
so-called structural behavior over a very wide range
of shear rate.
2.3.2 Transient Flow Behaviour
Shear viscosities of complex fluids for dysphagia
nutritional support in many cases are not only a
function of the applied shear stress or shear rate, but
are also a function of the length of time for which the
shear rate or stress is applied on the sample. A suitable way of measuring time-dependent effects during
viscous flow is to follow the evolution of viscosity
with time, after applying a constant shear rate
(see Fig. 5). As can be deduced from this figure, the
viscosity decreases with time to a steady-state value.
This behavior is known as thixotropy. All fluids that
develop a certain level of complex microstructure can
show this behavior. Thixotropy is a reversible phenomenon; that is, it reflects the finite time taken by the
fluid to change its microstructure, which is fully
recovered after cessation of the perturbation. The
occurrence of thixotropy implies that the flow history
of the fluid has to be taken into account when making
predictions of its flow behavior.
Different models can be found in the literature
that adequately describe the thixotropic response of
complex fluids (Partal and Franco 2010). In this
sense, Figoni’s model has been successfully used to fit
the transient flow behavior of enteral puddings for
dysphagia nutritional support. Figoni’s model is a
stress-decay model with two kinetic functions:
r r
¼ r01 r
ðÞexp k1tðÞ
where k
e
þ r
and k2are kinetic constants at short and long
1
e1
r
ðÞexp k2tðÞ; ð34Þ
02
e2
times, respectively. Subindexes 0 and e refer to initial
and equilibrium stresses, respectively.
2.3.3 Nonlinear Viscoelasticity Modeling
One approach to describing nonlinear behavior
(transient and steady state) of rheologically complex
materials is based on continuum mechanics principles, aiming to establish a rheological constitutive
equation to replace the Boltzmann principle (Eq. 4).
Wagner (1979) proposed the introduction of a nonlinear memory function in the constitutive equation for
nonlinear viscoelasticity. Taking into account that
the relaxation of stress following a large step strain
(nonlinear relaxation modulus) can often be separated
into time-dependent and strain-dependent factors (see
Fig. 1, parallel lines in a log–log plot for different
strains), Wagner proposed the use of a memory function, defined as the product of the linear memory
function and the damping function (reflecting strain
influence), an empirical function whose parameters are
determined by fitting experimental data.
0
m(t-t
) is the memory function, related to the
linear relaxation modulus by differentiation:
mðt t
Þ¼
; ð35Þ
0
dt
dGðt t0Þ
0
where t is the time at which the stress is evaluated and
0
is a time prior to time t at which the stress is
t
evaluated.
500 E. Brito-de la Fuente et al.
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2.0
.
-1
= 0.6 s
γ
1.5
1.0
R (t)
0.5
0.0
0255075100125150
Fig. 6 Relationship between transient and steady-state stress
values, and Wagner’s model fitting, as a function of shear time
for a selected pudding sample. Squares model predictions,
crosses calculation from experimental values
time (s)
Iftime–strainseparabilityforthenonlinearrelaxation
modulus is possible, and considering only the simple
shear component, one can express the Wagner model as
t
Z
1
dGðt t0Þ
0
dt
hðcÞcðt; t0Þdt0; ð36Þ
rðt;_cÞ¼
Nevertheless, Quinchia et al. (2011) have also used
a damping function described by the Soskey–Winter
model, which fits fairly well the experimental results
obtained with different types of emulsions, and more
specifically, with puddings for dysphagia nutritional
support:
1
hðcÞ¼
1 þac
: ð41Þ
b
Figure 6 shows the experimental and calculated
values of R(t), the ratio between the shear stress after
instantaneous imposition of a constant shear rate, r(t),
and the steady-state stress, r(?), for a transient flow
test conducted on a selected pudding. As can be
observed, the Wagner model fits the experimental
results obtained fairly well.
3 Rheology, Swallowing,
and Dysphagia: State of the Art
3.1 Rheology and the Swallowing
Process
where sðt;_cÞ is the transient shear stress and h(c)is
the damping function, which can be easily calculated
from the ratio between the nonlinear relaxation
modulus, G(c, t-t
lus, G(t-t
0
) (Rolón-Garrido and Wagner 2009):
0
), and the linear relaxation modu-
hðcÞ¼
Gðc; t t0Þ
Gðt t
: ð37Þ
0
Þ
Different types of damping functions have been
proposed. For instance, according to Wagner,
hðcÞ¼expðkcÞ; ð38Þ
and assuming that the evolution of the linear relaxation modulus with time can be described by a generalized Maxwell model,
n
X
ðtt0Þ
k
GðtÞ¼
i¼1
i
gie
: ð 39Þ
The steady-state viscosity is then
n
gðc
:
Þ¼
X
gik
i
1 þkkic
ðÞ
i¼1
:
: ð 40Þ
2
There are several angles from which dysphagia may
be analyzed. The medical side is perhaps the one has
attracted most scientists and researchers in this field
and this includes several medical disciplines such as
neurology, radiology, and gastroenterology as well
as speech and language pathologists and therapists.
Nowadays, it is well accepted that the dysphagia
management process begins with an interdisciplinary
assessment from which a treatment plan is designed
and developed with the goal of minimizing the
risk of aspiration, pneumonia, malnutrition, and
dehydration.
However, knowing that dysphagia is a combination
of symptoms affecting a person’s ability to swallow,
one may analyze dysphagia from another angle,
which is from a fluid kinematics/dynamics point of
view. This may be considered as the ‘‘dysphagia
engineering point of view.’’ Fluid kinematics deals
with describing the motion of fluids without necessarily considering the forces and moments that cause
the motion. Fluid kinematics describes velocity,
acceleration, and visualization of fluid motion. On the
other hand, fluid dynamics deals with the analysis of
the specific forces necessary to produce the motion.
Rheological Aspects of Swallowing and Dysphagia 501
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A kinematic/dynamic analysis of dysphagia aims to
gain insight into the mechanisms of bolus and liquid
flow during swallowing. Because rheology is the study
of the deformation and flow of matter, the connection
between the dysphagia world and rheology is clear.
The velocity spectrum of bolus flow in the pharynx
and esophagus has been determined using different
techniques. The ‘‘gold standard’’ videofluoroscopy is
the technique that has been most frequently used.
Other nonradiological techniques such as high-resolution manometry (Takasaki et al. 2008; Bredenoord
and Smout 2008; Bardan et al. 2006) and intraluminal
impedance (Omari et al. 2006) have also been used to
generate bolus transit velocity data, followed by a
swallowing kinematic analysis but with lower frequency. An ultrasonic pulse Doppler imaging method
has recently been added to list (Hasegawa et al. 2005).
Regardless of the technique used for kinematic
analysis of dysphagia, it is clear that the bolus transit
time and thus the velocity is highly dependent on the
patient’s medical conditions and the rheological
properties of the bolus.
A nonexhaustive literature review of kinematic
analysisof dysphagiaisgiven in Table 1. Thepurposeis
to show how the bolus transit velocity changes
depending on the swallowing phase and the rheological
properties of the bolus. The results in Table 1 clearly
suggest that the bolus transit velocity is considerably
higher for the pharyngeal phase than for the esophageal
phase. On the other hand, as the bolus viscosity increases, the bolus transit velocity decreases, as expected.
With use of some of the information given in
Table 1, and under the assumption that bolus deformation only occurs in shear, an estimation of the
shear rates that may be associated with swallowing
was performed, and the results are shown in Table 2.
As the results clearly suggest, bolus deformation (i.e.,
shear rate) during the swallowing process is greater
for the pharyngeal phase than for the esophageal
phase. In general, one may see that the shear rate
spectrum for the whole swallowing process goes from
1 to 1,000 l/s. This is in line with previous estimations
(Steele et al. 2003). Experimental values in vivo are
not available owing to the complex and irregular
oral geometry and the lack of reliable techniques.
However, several authors have tried to estimate shear
rates associated with the swallowing process. Nicosia
and Robbins (2001) using arheological approach based
upon parallel platesto simulate the squeezingeffectofa
food bolus from the oral cavity into the pharynx predicted shear rates of 180,000 and 3,000 s
viscosities of 1 9 10
-3
and 1 Pa s, respectively.
-1
for bolus
These values are very unlikely in reality. On the other
hand, Meng et al. (2005) estimated a shear rate around
-1
400 s
for water; this value may be more reasonable
than those shown in Table 2.
Regardless of the progress achieved from rheological sciences applied to bolus properties and
experimental in vivo kinematic studies, health professionals in charge of the dietary management of
dysphagia have hardly integrated this information in
their guidelines for diet modification. As an example,
the only association using a viscosity dimension is the
USA is the American Dietetic Association (National
Dysphagia Diet Task Force), which proposed different bolus viscosity categories on the basis of viscosity
values estimated at only one shear rate of 50 s
-1
More details are given in the next section.
A kinematic systematic study with well-defined
bolus rheological properties is still not available in the
literature. Thereader shouldnote thatalso elongational
flows are involvedinthe deformation ofafood bolus, as
clearly seen from videofluoroscopy and real-time
magnetic resonance imaging ( Imam et al. 2005; Buettner et al. 2001). The shape of the deformed bolus is
typical of the shapes produced under elongational
stretching. This isinlinewith the factthatmany boluses
exhibit extensional properties (Ekberg et al. 2009;
Chen 2009). Unfortunately, little attention has been
given to the role of elongational flows and dysphagia.
So far,viscous properties are the only considered in the
dysphagia world and with still too many limitations.
Rheology and swallowing are also connected at the
diagnosis level. The ‘‘gold standard’’ technique is a
videofluoroscopic swallowing study (VFSS). The
swallowing process can be visualized using videoradiography, either by using a ready-to-use commercial
contrast medium or by mixing food with barium sulfate
(BaSO
), making it radiopaque. Unfortunately, there is
4
no standardization for how to perform a VFSS. For
example, in USA, it is common to use commercial
ready-to-use contrast media, but this is not the case in
Europe. This lack of standardization leads to variability
in practiceand results and encourages individual speech
pathologists, dieticians, and dysphagic food manufacturers to determine their own dietary consistencies.
However, what it is more important to mention here
is the fact and recognition that the rheological
.
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Table 1 Kinematic analysis of dysphagia
Reference Bolus transit velocity
Pharyngeal phase
Nguyen et al.
(1997)
William et al.
(2001)
Omari et al. (2006) 8.13
Hasegawa et al.
(2005)
Bardan et al.
(2006)
Esophageal phase
Li et al. (1994) 1–4 Peristaltic wave velocities from videofluoroscopy—Kahrilas et al. (1988)
Nguyen et al.
(1997)
Srinivasan et al.
(2001)
Mizunuma et al.
(2009)
MII multiple intraluminal impedance, UES upper esophageal sphincter, BTT bolus transfer time, CFD computational fluid
dynamics
a
BTT(tail) = 0.664 s; h = 5.4 cm
b
BTT(average) = 6.24 s; h = 18 cm; v = 1–4 ml applesauce
c
BTT(head) = 0.5 s; h = 4 cm up to the epiglottis
(cm/s)
37.1 ± 1.1 Bolus head traversing the pharyngeal region. Data from multiple
28.3 ± 2.1 Bolus head velocity decreases as viscosity increases
9.6 ± 1.0 Mean pharyngeal propulsion velocity of bolus body
42 Bolus head entering the UES. Data from high-resolution manometry
a
50 Transit time of 1 s
37.6 ± 8.1 Bolus head traversing the pharyngeal region. Data from videofluoroscopy
10.3 ± 3.0 Bolus tail average velocity as the bolus traversed the pharynx and passed
9.6 ± 1.4 Head liquid bolus (low viscosity); subjects in supine position. Data from MII
14.2 ± 2.2 Head liquid bolus (low viscosity); subjects in upright position
6.3 ± 0.8 Head high-viscosity bolus (yogurt); subjects in supine position
5.0 ± 0.4 Body liquid bolus (low viscosity); subjects in supine position
5.2 ± 0.8 Body liquid bolus (low viscosity); subjects in upright position
4.0 ± 0.2 Body high-viscosity bolus (yogurt); subjects in supine position
4.1 ± 0.1 Tail liquid bolus (low viscosity); subjects in supine position
4.7 ± 0.2 Tail liquid bolus (low viscosity); subjects in upright position
4.1 ± 0.2 Tail High viscosity bolus (yogurt); subjects in supine position
b
2.9
c
8
Comments
intraluminal impedance
Bolus tail estimated from MII and videofluoroscopy
through the UES
Estimation from BTTs for applesauce. Data from MII
Head liquid bolus—estimations based on bolus transfer time from CFD for a
jelly
properties of the radiopaque bolus prepared by mixing
contrast medium (e.g., barium sulfate, BaSO
normal food. In other words, means that barium sulfate
is added to normal food usually liquids and/or purees
and the final mixture is radiopaque, are quite different
from those of the normal food used as a vehicle for the
VFSS. If the results from the VFSS are extrapolated to
dietary recommendations using foods without added
barium, there may be a severe problem.
Ekberg et al. (2009) found significant differences
in the rheological properties of a model food versus
) with
4
the same food but mixed with BaSO
. In addition,
4
the sensory texture dimensions of this model food
were significantly affected by the added barium.
Ould-Eleya and Gunasekaran (2007) reported significant differences in the rheological properties of both
prethickened and videofluoroscopy fluids currently
used for diagnosis and treatment of dysphagia.
Sopade et al. (2007) studied the rheological properties
of typical food powder thickeners and proposed
equations to prepare matching VFSS fluids and obtain
objective classification of the thickened fluids. More
Rheological Aspects of Swallowing and Dysphagia 503
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recently, our group (Brito-de la Fuente et al. 2010,
2011) proposed a rheological similarity approach by
closing the gap with the rheological properties of
VFFS fluids for the design of oral nutritional supplements having complex formulations.
3.2 Rheology in NutritionalSupport-Product Design
Malnutrition and dehydration are quite often a
consequence of dysphagia. Neurogenic dysphagia
impairs swallowing and thus reduces oral feeding,
leading to malnutrition and/or dehydration (Ickenstein
2011; Cabre et al. 2010). However, dysphagia
remains mainly a transport problem that has to be
solved first, before thinking of nutrition, in particular
if the swallowing function should be stimulated.
Ideally, if the two problems can be solved at once by
transferring under safer conditions high-quality
nutrient boluses, then the quality of life of dysphagic
patients may significantly increase (Brito-de la Fuente
et al. 2010).
The nutritional management of dysphagic patients
is fundamentally based upon the so-called diet modification of texture or consistency. However, in the
frame of the concepts presented in this chapter, it is
clear that modification of texture or consistency
means, in general, changes in the rheological properties of the diet. Assessment of consistency, quite
often called ‘‘viscosity,’’ still remains quite subjective
in the dysphagia world. The preparation, assessment
of consistency/viscosity, and administration of
thickened drinks to patients is universally subjective,
and unfortunately, health care professionals responsible for prescribing the patient’s modified diet
have shown poor or little knowledge of this field and
thus the wide range of viscous properties for the
same dysphagia level or recommendation (Steele and
Cichero 2008; Steele et al. 2003)
The rationale behind altering or modifying the
consistency of foods and/or drinks is to change the
rate at which food is transported through the pharynx
and thus to reduce the risk of patients aspirating food
because of their diminished swallowing reflex. Ideally, the most appropriate modification of food consistencies should follow from a clear assessment of
the swallowing problem, as reviewed by Penman and
Thomson (1998). However, this is not possible in all
Table 2 Estimated swallowing shear rates from bolus transit
velocities
Swallowing
phase
Pharyngeal
Bolus head
(maximum)
Bolus tail
(average )
Esophageal
From BTT
(BTT = 6.12 s)
a
Anatomy—data from Battagel et al. (2002)
b
Data based on MII from Srinivasan et al. (2001)
c
Kinematics—data from Bardan et al. (2006)
d
From capillary and peristaltic flow equations
a
a
Liquid bolus kinematics
velocity, V
35.5 931.7
10 262
2.94 4.7
b
c
(cm/s)
Estimated
shear rate,
d
(l/s)
c
cases and quite often health care professionals rely on
national guidelines for the dietary management of
dysphagia.
For example, the National Dysphagia Diet Task
Force (2002) of the American Dietetic Association
proposed terms for liquids and other viscoelastic
fluids using viscosity measurements at 25°C and a
single shear rate of 50 l/s. No scientific evidence or
rationale has been given by the National Dysphagia
Diet Task Force for the temperature and shear rate
chosen for this scale. In fact, on the basis of sensorial
analysis from lingualperceptionviscosity, a widerange
of shear rates ranging from 5 to 1,000 s
proposed, and a value of 50 s
-1
is the most frequently
-1
have been
cited, perhaps because this value was adopted by the
National Dysphagia Diet Task Force. These conditions
have been challenged recently by our research group
and others (Brito-de la Fuente et al. 2010; Quinchia
et al. 2011; O’Leary et al. 2010; Steele et al. 2003). As
shown in Sect. 3.1, from bolus transit velocities, shear
rates may range from 1 to 1,000 l/s depending on the
swallowing phase (see Table 2).
Moreover, in the UK, the British Dietetic Association (2009) recently reissued its National Descrip-
tors for Texture Modification in Adults using again
subjective descriptors from sensorial analysis. Quantitative measurement of viscosity is acknowledged to
be presently impractical according to the British
Dietetic Association and thus it is not performed by
health care professional or others. This practice
remains at all levels in hospitals and nursing home
504 E. Brito-de la Fuente et al.
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4
10
Formulation
Formulation
Product Structure
Product Structure
Final
Final
Properties
Properties
Process
Fluid
Fluid
Rheology
Rheology
Process
Parameters
Parameters
Fig. 7 Dynamic triad strategy for the design of oral nutritional
3
10
2
10
η (Pa.s)
1
10
T(°C) = 25
Fresubin Creme Strawberry
Varibar Pudding
0
10
-2
10
Fig. 8 Steady-shear viscosity curves for VaribarÒpudding and
Ò
Fresubin
crème
10
-1
10
0
.
γ
(1/s)
10
1
10
2
10
supplements with rheological similarity to swallow barium test
feeds
T (°C) = 25
G' G''
10
3
Fresubin Creme Strawberry
Varibar Pudding
care settings, in spite of all the scientific evidence
regarding the complex rheological properties (i.e.,
non-Newtonian behavior and thus shear-dependent
viscosity) of different boluses found during swallowing (Quinchia et al. 2011; Ekberg et al. 2009;
2
10
G´, G´´ [Pa]
Steele and Cichero 2008; Germain et al. 2006; Clavé
et al. 2006; Bülow et al. 2003) and the clinical evidence suggesting that the pharyngeal swallowing
phase occurs at different bolus transit velocities and
thus shear rates as shown in Sect. 3.1.
In summary, one of the major challenges con-
10
1
-2
10
10
-1
10
0
10
1
10
2
10
ω [rad/s]
fronting the dietary management of dysphagia is
product consistency or more generally product rheological properties. This leads to the still fundamental
Fig. 9 Viscoelastic properties for VaribarÒpudding and
Ò
Fresubin
crème under dynamic linear oscillatory conditions
question: is it possible to design better products for
the dietary management of dysphagia under safety
conditions? One answer to this question may be the
design of nutritional products that are ready to swallow by following a rheological similarity approach;
this means by matching the rheological properties of
the fluids used for the diagnosis (e.g., swallow barium
test feeds used in videofluoroscopy examination) with
those of the bolus.
Brito-de la Fuente et al. (2010) have proposed a
dynamic triad strategy for closing the gap between the
rheological properties of the swallow barium test
feeds and the ready-to-use product being designed
(see Fig. 7). This strategy has been applied quite
successfully in the design and commercial production
of complex-structure oral nutritional supplements rich
in proteins with a pudding consistency (e.g., Fresub-
Ò
in
crème). The benchmark used for this design was
the ‘‘gold standard’’ barium-based E-Z-EM product
Varibar
Ò
pudding. The main rheological results of
this exercise are described next.
Regarding viscous properties, Fresubin
Ò
crème
showed shear-thinning behavior, i.e., a viscositydecreasing function of the shear rate, matching
the results for Varibar
Regarding viscoelastic properties, the G
Ò
pudding as seen in Fig. 8.
0
values
clearly confirm the gel-like behavior of both products,
which means they are structured systems. For both
products, the dynamic rheological properties can be
considered to be essentially similar, as seen in Fig. 9.
3
3
Rheological Aspects of Swallowing and Dysphagia 505
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These results suggest that it is possible to design
oral nutritional supplements that exhibit rheological
properties similar to those of BaSO
suspensions used
4
for diagnosis of dysphagia. A complete rheological
characterization of the final oral nutritional supplement was published elsewhere (Quinchia et al. 2011).
In a more recent publication, Brito-de la Fuente
et al. (2011) describes an in-depth rheological characterization of prethickened foods and videofluoroscopy diagnostic fluids, showing the important role
that rheology plays in the diagnosis and dietary
management of dysphagia.
4 Conclusions
Dysphagia and rheology are closed interconnected.
Regardless of the experimental technique used for the
assessment of dysphagia, bolus flow properties play
an important role to guarantee higher levels of safe
swallowing.
Kinematic analysis of more dysphagic patients is
needed to better understand how boluses with different rheological properties are transferred in different
neurological or medical conditions. New techniques
such as computational fluid dynamics applied to
complex swallowing situations may be of high value
for prediagnosis and diagnosis as well as an educational tool to increase the compliance patients under
diet-modification programs.
The creation or design of novel foods for dietary
management of dysphagia or the improvement of
existing ones depends on a better understanding of the
complex interrelationship between food structure and
performance. More sophisticated experimental techniques comingfrom materialsciences suchas rheology
play an importantrole in thedesign and developmentof
new products for management of dysphagia. On the
other hand, a betterunderstanding of the flowproperties
of the fluids used for the videofluoroscopic assessment
of dysphagia and later the recommendation of
specific diets shouldbe of highpriority in the dysphagia
world. Even though this knowledge is now being
used to rationally design safer dysphagia products, this
approach should be extended to different consistencies
and nutritional profiles.
Finally, the incorporation of more knowledge on
the role rheological properties play during swallowing
is crucial for proper management of dysphagia.
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The Dietitian’s Role in Diagnosis
https://t.me/med1917
and Treatment of Dysphagia
S. Burton, A. Laverty, and M. Macleod
Contents
1 Introduction.............................................................. 507
2 Role in Diagnosis ..................................................... 510
2.1 Screening.................................................................... 510
2.2 Assessment................................................................. 510
3 Role in Nutritional Management ........................... 510
3.1 Nutrition..................................................................... 511
3.2 Hydration ................................................................... 512
3.3 Medication ................................................................. 515
3.4 Quality of Life Issues................................................ 515
4 Education and Training Role................................. 516
5 Summary................................................................... 516
References.......................................................................... 517
Abstract
This chapter aims to provide an overview of the
registered dietitian’s role and the commonplace
feeding dilemmas presented at the practical level
when applying the modified textured prescription
for food and fluids in adults with dysphagia. The
dietitian is one of a range of professionals involved
in service provision, and there is an increased
emphasis on an interdisciplinary and transdisci-
plinary team approach to care for people with
dysphagia at both the acute and the community
level. The role of the dietitian can be wide-ranging,
from traditional nutritional management to a
whole-systems approach encompassing screening,
assessment, diagnosis and organisation of the
modified textures within a dynamic nutritional
framework. A person-centred approach is essential
to provide nutrition in a mode which not only
sustains nutrition and hydration integrity but also
serves to enhance the individual’s quality of life.
1 Introduction
S. Burton A. Laverty M. Macleod (&)
Abteilung Neurologie, m&i-Fachklinik Bad Heilbrunn,
Wörnerweg 30, 83670, Bad Heilbrunn, Germany
e-mail: marjorymacleod1950@yahoo.co.uk
O. Ekberg (ed.), Dysphagia, Medical Radiology. Diagnostic Imaging, DOI: 10.1007/174_2011_346,
Springer-Verlag Berlin Heidelberg 2012
The ideal approach to the management of dysphagia
involves a multidisciplinary team (MDT) (Kemp
2001). The registered dietitian is an integral member
of this team and fundamental to service provision in
both the acute and the community setting (Heiss et al.
2010). The knowledge, skills and role of the regis-
tered dietitian within dysphagia include:
• Advising on nutritional requirements to minimise
nutritional deterioration, including dehydration and
507
508 S. Burton et al.
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Support workers
health / social care
Social Worker
Physiotherapist
Doctor / GP
Occupational
Therapist
Psychologist
Nurse
Dietitian
Pharmacist
Dental hygienist Advocate
Speech & Language
Food service staff
Therapist
Fig. 1 Members of the multidisciplinary team (MDT) for dysphagia. (Adapted from Copeman and Hyland 2007)
different administration modalities such as oral,
enteral and parenteral.
• Having the knowledge and experience to interpret
height, weight and anthropometric measurements
when assessing nutritional status.
• Using a holistic approach to assess, problem-solve
and ensure that health and well-being needs are met.
• Using appropriate health facilitation skills within
the therapeutic framework.
• Contributing to the application of a legal framework.
• Identifying, referring and working in partnership
with health and social care colleagues, agencies and
organisations.
• Addressing inequalities in health and social care.
• Advocating both formally and informally.
• Supporting individuals
1
and carers in decision-making.
• Educating the individual, carers and other members
of the dysphagia team.
• Using augmented/alternative communication for
those with acquired and non-acquired cognitive
impairments.
• Working in dynamic environments with individuals
who may display unpredictable behaviours that
present a challenge.
• Ensuring continuity of care across professional and
organisational boundaries.
Membership of a typical MDT is shown in Fig. 1,
with the individual with dysphagia being pivotal in
assessment and all management decisions. A brief
summary of roles is shown in Table 1.
Although the terms ‘multidisciplinary’ and ‘interdisciplinary’ are often used interchangeably, there is
an important difference in function. The interdisciplinary team model expands the MDT process where
collaboration (rather than just sharing information on
uni-professional interventions) in setting team goals
and team action plans results in more effective man-
1
As dysphagia is managed in both the acute and the
community health (and social) care settings, the term ‘individual’ is used within the text to represent patient, client and
service user.
agement (Dyer 2003). As so many disciplines are
involved in the assessment and treatment of dysphagia, collaborative working within the MDT is essential to provide coordinated evidence-based and safe
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