ACQ Vol 11 No 1 2009

MULTICULTURALISM AND DYSPHAGIA

Keywords: T he most common reason for prescribing thickened fluids to dysphagic patients is to avoid respiratory infections and pneumonia as a result of aspirating thin liquids. Most clinicians working with dysphagic patients recognise that compliance with recommendations for thickened fluids can be challenging, particularly in patients with cognitive impair­ ments who may not understand why speech pathologists prescribe thickened fluids. Because of this, there has been considerable interest in “free water protocols” in recent years in Australia and overseas. These protocols advocate access to water rather than thickened fluids, provided certain strict conditions are met. The most well-known protocol is the Frazier Free Water Protocol, which is summarised in table 1. In 2005, via the Dysphagia listserv (http://www.dysphagia. com/), Janis Lorman, an American speech-language pathologist invited facilities that were using a free water protocol to complete a survey. There were 19 respondents: all indicated that the protocol was working and that there was no greater incidence of pneumonia. Full details of the survey are presented in table 2. To increase our understanding of why free water protocols have received so much interest, it is important to understand the factors that have led to the development of these protocols. These include the risk of dehydration in patients on thickened fluids, as well as risk factors associated with aspiration pneumonia, such as colonisation by bacteria. Dehydration To be well hydrated, an average adult male requires 2.9 litres of fluid per day, whereas an average adult female requires 2.2 litres (Kleiner, 1999). Poor compliance with thickened fluid recommendations may be associated with an increased risk of patients becoming dehydrated. Studies into the fluid intake of stroke patients have found a negative impact of prescription of thickened fluids such as a need for supplementary fluids (Whelan, 2001), and failure to meet daily fluid requirements F ree W ater P rotocols A review of the evidence Claire Langdon For many years in dysphagia management thickened fluids have been prescribed to patients who aspirate thin liquids. In the United States, certain facilities have allowed access to water for aspirating patients without an increase in adverse events. There is much interest in these “Free Water” protocols, which reportedly result in increased patient satisfaction and reduced dehydration. This article reviews aspiration pneumonia and factors that may contribute to development of respiratory infections. Free water protocols may be a useful alter­ native for patients with good oral care and minimal co- morbidities, though there is a need for further research to explore this. dysphagia, free water, aspiration pneumonia, dehydration

for patients on thickened fluids (Finestone, Foley, Woodbury, & Greene-Finestone, 2001). A recent randomised controlled trial (RCT) found that dehydration was more prevalent in subjects assigned to thickened fluids as opposed to postural strategies, and that the 3-month cumulative incidence of pneumonia in known aspirators was lower than expected (Robbins et al., 2008). Dehydration levels of as little as 1% may adversely impact on cognitive performance (Lieberman, 2007). It is therefore interesting to note in the free water protocol survey (table 2) that several facilities reported improved hydration/decreased dehydration and improved The first line of respiratory defence comes from barriers such as mucous and cilia (Boyton & Openshaw, 2002). Respiratory defences against solid particles include alveolar macrophages, while the lymphatic system copes with fluids (Curtis & Langmore, 1997). The immune response includes lactoferrin, lysozyme, collectins and defensins (Boyton & Openshaw, 2002). Cell surface fibronectin has been shown to prevent the adherence of gram-negative rods to receptors on oropharyngeal cells in normal hosts (Cassiere, 1998). However, in patients with underlying illness, cell surface fibronectin is cleaved off, leaving receptors to gram-negative rods exposed (Cassiere, 1998; Woods, 1987). Although many challenges are dealt with by the immune system, concentrated pathogens or a weakened immune system can mean that respiratory tract infections develop (Boyton & Openshaw, 2002; Cassiere, 1998; Duits et al., 2003; Finucane, Christmas, & Travis, 1999; Kikawada, Iwamoto, & Takasaki, 2005; Nicod, 1999). Patients with underlying respiratory disease such as chronic obstructive pulmonary disease (COPD) are not as likely to be able to clear aspirated pathogens; in fact, there is speculation that patients with COPD are chronically colonised by bacteria, with exacer­ bations occurring when the balance between the immune system and bacterial overgrowth is altered (Wilson, 1998). Smoking suppresses ciliary action (Terpenning, 2001) and impairs mucociliary clearance, the chief defence mechanism for solid particles (Crystal, West, Barnes, Cherniak & Weibel, 1991). Stroke patients with impaired cough reflex have been found to be at greater risk of aspiration pneumonia (Adding­ ton, Stephens, Gilliland, & Rodriguez, 1999; Addington, Stephens, & Gilliland, 1999). Colonisation by bacteria In the model proposed by Langmore et al. (1998) colonisation of the oropharynx by bacteria is the first step in a sequence that may lead to the development of pneumonia. The oral cavity is colonised by more than 400 species of aerobic and anaerobic bacteria (Brook, 2003). Most aspiration pneumonia is bacterial in origin (Millns, Gosney, Jack, Martin, & Wright, 2003). Reduction in salivary flow and poor oral clearance of bacteria are potentially the first steps that lead from oro­ pharyngeal colonisation to pneumonia (Palmer, Albulak, Fields, Filkin, Simon & Smaldone, 2001). Langmore et al. cognition as a result of access to water. Aspiration pneumonia The body’s defence systems

S p eech P athology A ustralia

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