1. INTRODUCTION:

So far, many efforts of alternative approaches such as the aroma therapy¹ or aroma massage² has been put into relieving the discomfort for hemodialysis patient suffering from pruritus, but these methods still have limitations³ of time or cost in clinical application. Therefore, the elaborated nursing intervention needs to be developed. Moon (1994)⁴ in 1994, and Park and Hong (2010)⁵ in 2010 performed their studies respectively under the assumption that the low temperature would slow down the conduction velocity of peripheral nerve fibers so that pruritus from the hemodialysis might be mitigated at the lower temperature dialysate but their study results were discordant to apply clinically.

Therefore, we tried to obtain the accurate effect of the lower temperature dialysate on pruritus in hemodialysis through the repeated study. On the other hand, fatigue is also one of the complications from the hemodialysis that has been consistently studied by many researchers⁶. According to previous studies, dialysis patients feel anger or depression due to unacceptable fatigue that they have to spend enormous amount of time to take the rest after hemodialysis⁷. It is very important to study to minimize this fatigue caused by hemodialysis not only making the dialysis patient helpless physically and mentally, but also lowering the compliance with the dialysis and the will to get treated^8,9,10.

In this study we tried to find out the measure to provide the theoretical guidance on the ideal temperature of dialysate to help dialysis patients suffering from the pruritus and fatigue as well as the hypotension through verifying the effect of the cool dialysate at a low temperature of 35.5°C compared to the current regular dialysate at 36.5 °C.

The hypotheses for this study are as follows.

1) The First hypothesis: The degree of pruritus after the cool dialysis with the lower temperature dialysate, will be lower than after the regular dialysis with the current regular temperature dialysate.

2) The Second hypothesis: The degree of fatigue after the cool dialysis with the lower temperature dialysate,

2. MATERIALS AND METHODS:

2.1. Study subject:

The subjects for this study were selected among the patients who have been received hemodialysis three times a week at the Dialysis room of K General Hospital in C city.

The sample size calculated using the G*Power 3.1 program after determining the effect size at .5, the significance level at .05, and power at .80, was 34 but 3 more patients added considering dropping out, so total 37 patients were recruited.

2.2. Study instrument:

2.2.1. Pruritus:

For assessing the pruritus, we used the scale of pruritus developed by Duo (1987)¹¹. The instrument consists of three items that measure the severity, site, and frequency of pruritus. The score range of the instrument is from 0 to 9, with higher scores indicating more severe pruritus. Cronbach's alpha of this instrument was .90.

2.2.2. Fatigue:

The Visual Analogue Scale-Fatigue developed by Lee, Hicks and Nino-Murcia (1991)¹²was used to evaluate the fatigue. This scale has the total 16 items measuring fatigue and energy level. Higher score means more fatigue. Cronbach's alpha of this instrument was .91.

2.3. Data collection methods:

This study was conducted in order to protect the study subjects ethically, after obtaining the approval of the Institutional Review Board of the K General Hospital Medical Research Ethics Committee.

2.3.1. Experimental treatment:

In this study, the artificial dialysis machine used for the patients was AK 96S manufactured by Sweden Gambro. During the entire study period of 4 weeks, for each subject of this study, the regular dialysis was implemented with the regular temperature dialysate at 36.5°C, 3 times per week for the first two weeks, and then, the cool dialysis was applied with the lower temperature dialysate at 35.5°C, 3 times per week for the next two weeks. All experimental procedures of dialysis were performed by six pre-trained artificial kidney room nurses, and all the other conditions were remained the same except the dialysate temperature.

2.3.2. Pre and Post Survey:

As in other previous studies, all subjects were requested to answer four surveys that the pre-surveys were performed immediately before the regular- dialysis and the cool dialysis during 4 week experimental period and also the post-surveys were conducted immediately after the last regular- dialysis and the cool dialysis.

At the pre-survey examined, the informations of general characteristics and characteristics of dialysis were obtained as well as the degree of pruritus and fatigue and only the degree of pruritus and fatigue were evaluated at the post–surveys.

2.4. Data analysis methods:

The collected data were analyzed using the SPSS WIN 19.0 program as follows.

1) General characteristics were examined with the frequency, percentage,mean and regular- deviation.

2) The homogeneity of dialysis-related characteristics was analyzed by x2-test and t-test.

3) The difference of the scores between the cool dialysis at low-temperature and the regular-dialysis at the temperature of 36.5°C was analyzed by the paired t-test.

Table 1: General characteristics of hemodialysis-related characteristics (N=37)

Characteristics	Categories	n	%
sex	Male	20	54.1
sex	Female	17	45.9
Age(yr)	≤ 39	9	24.3
	40-49	8	21.6
	50-59	7	18.9
	60-69	8	21.6
	≥70	5	13.5
	M±SD	51.9±14.86
Marital status	Single	10	27.0
	Married	20	54.1
	Divorce or Widowed	7	18.9
Religion	Yes	20	54.1
Religion	No	17	45.9
Education	Elementary school	5	13.5
	Middle school	8	21.6
	High school	18	48.6
	College or more	6	16.2
Economic status	High	2	5.4
	Middle	33	89.2
	Low	2	5.4
Insurance state	Medical insurance	23	62.2
Insurance state	Medical care	14	37.8
Cause of CRF	DM	23	62.2
	Hypertension	12	32.4
	Glomerular nephritis	1	2.7
	Others	1	2.7
Duration ofhemodialysis (year)	<1	4	10.8
	1-3	11	29.7
	4-5	6	16.2
	6-10	9	24.3
	>10	7	18.9
	M±SD	5.49±4.40

3. RESULTS AND DISCUSSION:

The general characteristics of the subjects are shown in Table 1. There were 20 males (54.1%) and 17 females (45.9%). The mean age of the subjects was 51.9 years. The marital status was 20 married (54.1%), and subjects who religion were 20(54.1%). The high school graduates were the most with 18 (48.6%), and there were 33 whowere in the middle level of economic status (89.2%). The most common cause of CRF was diabetes mellitus in 23 subjects (62.2%). Subjects with hemodialysis duration of 1-3 year were the most with 11 (29.7%), and mean hemodialysis duration was 5.49 years.

There was no significant difference in the homogeneity analysis between two groups in the extraneous variables reported that could affect the fatigue and pruritus as seen in table 2.

Table 2: Homogeneity test of hemodialysis-related characteristics (N=37)

Variable	Cooldialysis	Regular dialysis	t	p
Variable	M±SD	M±SD	t	p
Systolic BP (mmHg)	148.05±28.29	148.64±24.76	0.12	.900
Diastolic BP (mmHg)	80.05±13.09	79.48±12.70	-0.25	.804
Temperature(°C)	36.09±0.37	36.00±0.32	-1.23	.223
Body weight (kg)	60.9±10.68	61.1±10.99	0.87	.390
Drug (μg)	2583.33±1441.72	2222.22±1605.64	-2.01	.051
Pruritus	4.56±0.55	4.59±0.55	0.42	.067
Fatigue	59.11±35.43	56.00±29.25	-0.45	.656

Table 3: Difference of pruritus and fatigue between the two study groups (N=37)

Variable	Dialysis temperature	Pre	Post	t	p
		M±SD	M±SD
Pruritus	Cool dialysis	4.56±0.55	3.89±0.62	2.80	.008
	Regular dialysis	4.59±0.55	4.83±0.64
Fatigue	Cooldialysis	59.11±35.43	74.05±31.71	2.71	.010
	Regular dialysis	56.00±29.25	83.89±35.91

1) The first hypothesis: The pre-dialysis scores of pruritus were respectively 4.59, before the regular dialysis, and 4.56, before the cool dialysis. There was no significant difference statistically in the pre-dialysis scores of pruritus before the dialysis between the two groups. But the post-dialysis scores of pruritus were respectively 4.83, after the regular-dialysis, and 3.89, after the cool-dialysis. The post-dialysis score of pruritus after the cool-dialysis was significantly lower than after the regular-dialysis as seen in table 3 (t=2.80, p=.008). These results support the first hypothesis that the degree of pruritus after the cool dialysis will be lower than after the regular dialysis.

2) The second hypothesis: The fatigue scores of the pre-dialysis were respectively 59.11 in the cool dialysis group and 56.00 in the regular dialysis group. There was no significant difference statistically between the fatigue scores of the pre-dialysis in the two groups. After dialysis, the fatigue scores were 74.05 after the cool dialysis and 83.89 after the regular dialysis. The fatigue score of the post cool dialysis was significantly lower than that of the post regular dialysis as seen in table 3 (t=2.71, p=.010). The second hypothesis that the degree of fatigue after cool dialysis would be lower than that of the post regular dialysis was supported.

In this study, all subjects received their dialysis at the regular dialysis with the dialysate temperature at the 36.5℃, three times per week for 2 weeks, and then the cool dialysis with the dialysate temperature at the 35.5°C, three times per week for another 2 weeks to verify the effect of the cool dialysis solution on the pruritus and the fatigue. In the results, the score of pruritus was significantly lower after the cool dialysis than that of the ordinary dialysis. These results are consistent with the results of Moon (1994)⁴ which the degree of pruritus was analyzed with the difference of temperature of dialysate after their subjects were exposed to the lower temperature dialysate and the regular temperature dialysate for two weeks, respectively. These also support empirically Park’s opinion (2010)¹³ that pruritus might be mitigated with dialysate at low temperature than at the regular temperature because pruritus causing factors might be less released due to the vasooconstriction with the cool dialysate.

The scores of fatigue in our study were also significantly lower after the cool dialysis than after the regular dialysis. These results are consistent with the study findings of Azar (2009)¹⁴ which identified the difference in the fatigue for the same subjects exposed at the different temperature dialysates. It could be inferred that the higher temperature dialysate could raise the core temperature that makes cardiac output increased resulting blood vessels expanded, leading to hypotension causing patients to feel more fatigue.

The association between the fatigue, body temperature and blood pressure after dialysis with the different temperature dialysates was found that the body temperature increased, the blood pressure went down and the scores of fatigue were higher after dialysis with the regular temperature dialysate than the cool dialysate. Even after the cool dialysis with the dialysate temperature at 35.5°C, the body temperature increased by 0.31°C than before the dialysis. Considering these results, if the dialysis is performed with the lower temperature dialysate than the current regular dialysis with the dialysate temperature at 36.5°C, body temperature, blood pressure as well as pruritus and fatigue after dialysis might be improved.

4. CONCLUSION:

In this study, we used the crossover design that the same subject was exposed to the regular temperature dialysate for 2 weeks and then the lower temperature dialysate for next 2 weeks to examine the effects of the cool dialysis on the pruritus and fatigue in hemodialysis patients. The results have shown that the use of the lower temperature dialysate is effective in reducing pruritus and fatigue compared to the regular temperature. Based on the results of this study, we suggest the followings.

First, it needs to study that the effects of the lower temperature dialysate on other physical discomforts related with hemodialysis besides fatigue and pruritus, such as nausea, vomiting, headache, dizziness, or muscle spasms.

Second, we investigated only the difference between the current standard temperature dialysate at 36.5°C and the lower temperature dialysate at 35.5°C in this study, but the further study with setting the dialysate temperature more variously might be needed in order to investigate the optimal temperature of dialysate for maximizing the therapeutic effects of hemodialysis and minimizing the side effects.

5. ACKNOWLEDGMENT:

This study was supported by the Konkuk University.

6. REFERENCE:

1. Shahgholian N, Dehghan M, Mortazavi M, Gholami F, Valiani M, Effect of aromatherapy on pruritus relief in hemodialysis patients. Iranian journal of nursing and midwifery research, 2010, 15(4), pp. 240-244.

2. Kang SJ, Kim NY,The effects of aroma hand massage on pruritus, fatigue and stress of hemodialysis patients. Korean Journal of Adult Nursing, 2008, 20(6), pp.883-894. http://www.koreascience.or.kr/article/ArticleFullRecord.jsp?cn=SOKHBY_2008_v20n6_883

3. Lau T, Leung S,Lau W, Gabapentin for uremic pruritus in hemodialysis patients: a qualitative systematic review. Canadian Journal of Kidney Health and Disease, 2016, 3: 14.

4. Moon O, Effect of cool dialysis on uremic pruritus in hemodialysis patients. Korean Nephrology Nurses’ Association, 1994, 9, pp.7-18. http://scholar. google.co. kr/scholar?q=Effect+of+cool+dialysis+on+uremic+pruritus+in+hemodialysis+patients.+ and btnG= and hl=ko and as_sdt=0%2C5

5. Park JY, Hong HS, The effects of Cool Dialysis on Pruritus of Chronic Renal Failure Patients. Journal of Korean Biological Nursing Science, 2010, 12(1), pp.31-38. http://www.koreascience.or.kr/article/ArticleFullRecord.jsp?cn=GCJOBO_2010_v12n1_31

6. Hadadian F, Sohrabi N, FarokhpayamM, Farokhpayam H, Towhidi F, Fayazi S, Soroush A, Abdi A, The effects of transcutaneous electrical acupoint stimulation (TEAS) on fatigue in hemodialysis patients. Journal of Clinical Diagnostic Research, 2016, 10(9), YC01-YC04.

7. Horigan AE, Fatigue in hemodialysis patients: a review of current knowledge. Journal of Pain and Symptom Management, 2012, 44(5), pp.715-724.

8. Toth-ManikowskiSM, SozioSM, Cool dialysate during in-center hemodialysis: Beneficial and deleterious effects. World Journal of Nephrology, 2016, 5(2), pp.166-171.

9. Roumelioti ME, Unruh ML, Lower dialysate temperature in hemodialysis: Is it a cool idea?. Clinical Journal of the American Society of Nephrology, 2015, 10(8), pp.1318-1320.

10. Maheshwari V, Lau T, Samavedham L, Rangaiah GP, Effect of cool vs. warm dialysate on toxin removal: rationale and study design. BMC Nephrology, 2015, 16: 25.

11. Duo LJ, Electrical needle therapy of uremic pruritus. Nephron, 1987, 47(3), pp.179-183.

12. Lee KA, Hicks G, Nino-Murcia G, Validity and reliability of a scale to assess fatigue. Psychiatry Research, 1991, 36(3), pp.291-298.

13. Park HY, The effect of cooling sense on the perception of itching and skin blood flow. Unpublished master’s thesis, Chonnam National University, Gwangju, 2010. http://www.riss4u.net/search/detail/DetailView.do?p_mat_type=be54d9b8bc7cdb09 and control_no=3f46eb857dfe8792ffe0bdc3ef48d419

14. Azar AT, Effect of dialysate temperature on hemodynamic stability among hemodialysis patients.Saudi Journal of Kidney Disease and Transplantation, 2009, 20(4), pp.596-603.

Received on 12.12.2017 Modified on 13.01.2018

Research J. Pharm. and Tech 2018; 11(5):1851-1854.

DOI: 10.5958/0974-360X.2018.00344.X

The effect of Cool Dialysis on Pruritus and Fatigue in Hemodialysis Patients

Table 1: General characteristics of hemodialysis-related characteristics (N=37)

Table 2: Homogeneity test of hemodialysis-related characteristics (N=37)

Table 3: Difference of pruritus and fatigue between the two study groups (N=37)