ACQ Vol 11 No 1 2009

MULTICULTURALISM AND DYSPHAGIA

percutaneous endoscopic gastrostomy (PEG) tubes and 17.5% of patients fed orally (Leibovitz, Plotnikov, Habot, Rosenberg, & Segal, 2003). A study of factors that predicted development of pneumonia in a sample of 102,842 American nursing home residents found 18 significant predictors. These included suctioning, COPD, congestive heart failure (CHF), presence of a feeding tube, bedfast, reduced alertness, weight loss, dysphagia, number of medications/day, urinary tract infection (UTI) and dependence for activities of daily living (ADLs). Compared to an earlier study (Langmore et al. 1998), dependent for feeding, presence of a feeding tube and number of medications were significant predictor variables in both studies (Langmore, Skarupski, Park, & Fries, 2002). Dentures. A study of 233 elderly in a long-term hospital ward found 72% of patients who wore dentures had denture stomatitis, while many of those with natural teeth were affected by caries. They concluded high oral yeast counts and prevalence of oral candidiasis were associated with poor oral hygiene and neglect of denture care (Budtz-Jorgensen, Mojon, Banon-Clement & Baehni, 1996). Preston, Gosney, Noon, and Martin (1999) found a correlation between presence of oral gram-negative bacteria and use of dentures. Forty-three percent (n = 12) of subjects had intra- oral gram-negative bacteria, and 43% had Candida albicans. They found that 61% of subjects who wore dentures had debris covering part of their denture (Preston et al., 1999). Sumi, Sunakawa, Michiwaki, and Sakagami (2002) evaluated the dentures of 50 dependant elderly patients who required full assistance for denture care. They isolated aerobic bacteria from all 50 patients, with potential respiratory pathogens colonising dental plaque in 23 of 50 cases (Sumi, 2002). Saliva and xerostomia. Saliva plays an important role in homeo­ stasis (“state of balance”) of the oral cavity. It contains many components including immunoglobulins, lactoferrin, lacto­ peroxidase, lysozyme and proteins. Saliva provides a fluid environment for lubrication of the oral cavity to aid in speech, swallowing and cleansing of the oral tissues. Salivary proteins possess antibacterial properties and inhibit microbial adherence (immunoglobulins) (Diaz-Arnold & Marek, 2002). Saliva seems to undergo chemical changes with ageing, with the amount of ptyalin decreasing and mucin increasing, causing saliva to become thick and viscous (Astor, Hanft, & Ciocon, 1999). It has been reported that saliva production does not decrease with normal ageing (Vissink, Spijkervet, & Van Nieuw Amerongen, 1996), rather xerostomia (a lack of saliva in the mouth) is a side effect of many of the medications taken by the elderly; more than 400 medications are associated with oral dryness (Diaz-Arnold & Marke, 2002). Multiple medications are commonly prescribed to many older patients, with resulting xerostomia a common problem (Sreebny & Valdini, 1987). Other causes of xerostomia include mouth breathing, radiation therapy, dehydration and autoimmune diseases (e.g., Sjogren’s syndrome), and systemic illness (e.g., diabetes, nephritis and thyroid dysfunction) (Astor et al., 1999). Xerostomia can lead to dysgeusia, glossodynia, sialadenitis, cracking and fissuring of the oral mucosa and halitosis, difficulties with denture retention and problems with mastication and swallowing (Astor et al., 1999). The presence of saliva appears to be a defence against colonisation with bacteria (Smaldone, 2001). There was a greater than two-fold increase in adherence of Klebsiella pneumoniae to buccal cells of patients with xerostomia compared with normal subjects and colonisation by gram-negative bacteria in patients receiving head and neck radiation treatments increasing from 8% prior to treatment to 36% during treatment (Gibson & Barrett, 1992).

Progression of aspiration to pneumonia Logically, it would seem that dysphagic patients who are very sick are at higher risk of mortality than patients with swallow­ ing impairment who are otherwise well; however, this distinction is not clearly described in the literature (DeLegge, 2002). Despite an association between aspiration and the development of pneumonia, it is not an inevitable sequence (Cook & Kahrilas, 1999) even if subjects demonstrate aspiration on modified barium swallow (Addington, Stephens, & Gil­ liland, 1999; Teasell, McRae, Heitzner, Bhardwaj, & Finestone, 1999). It has been estimated that only 25% to 50% of all aspirations progress to pneumonia (Cassiere, 1998). Most mortality rates reported for aspiration pneumonia are in very ill, hospitalised patients (DeLegge, 2002). In a study of 304 acute stroke patients, 29 (9.5%) developed aspiration pneumonia in the first year post stroke. Neither penetration nor aspiration on videofluoroscopy correlated with development of pneumonia (Johnson, McKenzie, & Sievers, 1993). In a study using videofluoroscopy to examine 55 male patients within the 5 days post stroke, Daniels, Brailey, Priestly, Herrington, Weisberg and Foundas (1998). found aspiration occurred in 21 patients (38%) with 14 of these aspirating silently. Notably only one patient developed aspiration pneumonia during hospitalisation. Low, Wyles, Wilkinson and Sainsbury (2001) found subjects with documented aspiration who did not comply with dysphagia recommendations were more likely to be admitted to hospital with chest infections. However, they were not statistically more likely to develop a chest infection or require a course of antibiotics than those who always complied with recommendations. The non-compliant subjects tended to be younger, living at home and therefore presumably in better general health (Low et al. 2001). To date, there has been one randomised control trial in­ vestigating the effect of access to free water by stroke patients who were documented aspirators. The control group received thickened fluids only, while the intervention group had all liquids thickened, but were allowed free access to water in addition to the thickened liquids. No patient in either group developed pneumonia, dehydration or complications during the study, or in a 30-day follow-up period (Garon, Eagle, & Ormiston, 1997). However, participant numbers were small, with only 10 subjects in each group, and the patients were at least 3 weeks post stroke when enrolled in the study, so they may have experienced some spontaneous recovery of swallow function. Aspiration pneumonia in paediatric populations An investigation into development of pneumonia in a paediatric population with known dysphagia found that the impact of aspiration on development of pneumonia is correlated with the presence of other factors, such as gastroesophageal reflux, asthma and Downs syndrome (Weir, McMahon, Barry, Ware, Masters & Chang, 2007). However, a Cochrane database investigation found there is currently insufficient evidence to support or contradict use of free water in paediatric populations (Weir, McMahon, & Chang, 2005). Impact of aspiration of thickened liquids A randomised control trial noted that patients who aspirated very thick liquids were the most likely to go on to develop pneumonia (DePippo, Holas, Reding, Mandel & Lesser, 1994). A recent trial has also noted that participants who aspirated honey thick fluids were at greater risk of developing respiratory complications than those on thin fluids and on nectar thick fluids (Robbins et al., 2008).

S p eech P athology A ustralia

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