Haemodialysis is the most preferred method in the treatment of kidney failure in the world
and in Turkey. According to the 2019 reports of the United States renal data system,
haemodialysis is applied to 86.9% of the chronic kidney patients. In Turkey, this rate was
74.8% as of the end of 2018, according to the data reports of the Turkish Society of
Nephrology. Patients undergoing haemodialysis have to cope with the adverse effects of the
chronic disease as well as complications that develop due to treatment. Causes such as drugs
used in haemodialysis treatment, fluid restriction, high ultrafiltration, weight gain between
two haemodialysis sessions, dialysis imbalance syndrome and deterioration of oral pH, cause
fluid-electrolyte imbalances, hypotension, pain, muscle cramps, thirst, dry mouth and leads
of bothersome symptoms such as nausea. These may increase morbidity and mortality by causing
premature termination of haemodialysis treatment or dialysis failure. Patients undergoing
haemodialysis should be able to alleviate thirst, dry mouth and nausea with a method that
does not disrupt fluid restriction. The combination of the salivary gland stimulant effect of
the refreshing xylitol alone together with the mechanical effect of chewing gum has the
effect of reducing thirst and dry mouth. Effective in reducing thirst, dry mouth and nausea
in patients undergoing haemodialysis and a method that nurses can choose independently,
xylitol gum can be easily used as a safe method and increases intraoral pH, prevents oral
mucositis, facilitates periodontal healing and contributes to an effective treatment process.
Thirst, dry mouth and nausea are quite common bothersome symptoms in patients undergoing
haemodialysis. Thirst is a symptom associated with the desire to drink water due to
insufficient body fluids and is one of the body's defence mechanisms. The inability of the
saliva secreted to maintain the moistness of the oral mucosa is defined as "thirst". Thirst
is controlled centrally and perceived peripherally as the feeling of dry mouth. According to
Bots et al., 47.8% of patients on haemodialysis were thirsty during the day, 41.6% felt
thirsty before dialysis, 24.7% during dialysis and 29.9% after dialysis. Dry mouth is a
symptom that results from excessive reduction in the amount of saliva or problems with
secretion, usually due to under-functioning of the salivary glands. When the amount of saliva
decreases below 0.1 mL/min when evaluated together with clinical symptoms, it is defined as
"dry mouth (xerostomia)". Bots et al. determined that 76.4% of the patients on haemodialysis
treatment experienced dry mouth, while this figure was 56.2% according to Akgöz and Arslan.
Thirst and dry mouth in patients on haemodialysis causes several clinical symptoms such as
the sensations of sticky or burning tongue, need to drink liquid, difficulty swallowing solid
food, stomatitis, increased dental caries, dysarthria and night sleep interruptions. Nausea
is the conscious recognition of the excitation of a part of the vomiting centre or a closely
related area and subjective feeling of the need to vomit. Increased urea concentration in the
saliva of the patients and worsening of oral pH and exposure of the oral cavity to pathogens
increase the risk of developing infection, disrupt the integrity of the mucous membrane and
intensify the feeling of nausea Of the patients on haemodialysis treatment, 21-54% according
to Almutary and 41% according to Akgöz and Arslan experienced nausea. Uncontrollable nausea
can cause undesirable symptoms such as fluid-electrolyte imbalance, dehydration, vomiting,
anorexia and weight loss, and also reduce the absorption and excretion of drugs used in the
treatment. Based on the previous studies in the literature, xylitol gum, used generally as an
auxiliary product in providing oral hygiene and preventing dental plaques and caries, has
proven effects such as increasing saliva pH, protecting salivary proteins, reducing mouth and
nasopharyngeal infections and protecting mucous membrane integrity. With its refreshing and
pleasant taste, xylitol gum is also recommended as a natural, economical, easily accessible
and safe product for reducing thirst, dry mouth and nausea in patients undergoing
haemodialysis. However, studies evaluating the effect of xylitol gum on thirst and dry mouth
in patients undergoing haemodialysis are limited in both the national and international
literature. In addition, studies conducted with different sample groups and different methods
(patients who underwent laparoscopic breast surgery, colonoscopy preparation, gynaecological
operations) concluded that chewing gum reduces nausea but no study evaluating the effect of
xylitol gum on nausea in patients undergoing haemodialysis could be found.
