A randomized controlled comparative study of different fluid exchange modes in urgent-start peritoneal dialysis in patients with end-stage renal disease: automated peritoneal dialysis combined with manual fluid exchange vs. manual fluid exchange alone

Figures & data

Table 1. Standard prescription for the patients of USPD.

Group	BSA	Schemes /day	Curative time /day	Total dialysate volume /day
A-MPD	<1.7m^2	M (700 mL × 2 exchanges) + A (3200 mL/ 600 min/ 5 cycles)	960 min	4600mL
	≥1.7m^2	M (1000 mL× 2 exchanges) + A (5000 mL/ 600 min/ 5 cycles)	960 min	7000mL
MPD	<1.7m^2	700mL × 4 exchanges	720 min	2800mL
	≥1.7m^2	1000mL × 4 exchanges	720 min	4000mL

A-MPD: automated peritoneal dialysis combined with manual fluid exchange peritoneal dialysis; MPD: manual fluid exchange peritoneal dialysis.

Figure 1. Flow diagram of enrollment, randomization, and follow-up of patients. MPD: manual fluid exchange peritoneal dialysis; A-MPD: combination of automated peritoneal dialysis (APD) with MPD; PDC: peritoneal dialysis catheter.

Table 2. Demographic and baseline characteristics.

,.	A-MPD	MPD	P value
Number of patients	36	38
Male, n (%)	21 (58.33%)	22 (57.89%)	0.970
Age (year)	39.58 ± 10.07	44.58 ± 14.04	0.084
Surgery
Open surgery n (%)	24 (66.67%)	31 (81.59%)	0.142
Laparoscopy surgery n (%)	12 (33.33%)	7 (18.42%)	0.142
Cause of ESRD n (%)
Diabetic nephropathy n (%)	3 (3.23%)	4 (13.79%)
Hypertensive nephrosclerosis n (%)	2 (6.45%)	4 (10.34%)
Chronic glomerulonephritis n (%)	18 (51.61%)	8 (17.24%)	0.139
Others n (%)	2 (6.45%)	3 (6.90%)
Unknown n (%)	11 (32.26%)	19 (51.72%)
Body mass index (kg/m^2)	22.34 ± 3.28	21.28 ± 3.24	0.169
Body surface area (m^2)	1.76 ± 0.21	1.72 ± 0.19	0.432
Hemoglobin (g/L)	90.89 ± 17.12	85.87 ± 16.05	0.197
Albumin (g/L)	40.11 ± 4.38	39.21 ± 4.79	0.401
Blood urea nitrogen (mmol/L)	32.21 ± 10.71	29.36 ± 9.52	0.230
Creatinine (μmo/L)	866.44 ± 230.68	827.63 ± 230.81	0.472
eGFR (mL/min/1.73 m^2)	5.77 ± 1.93	5.83 ± 1.67	0.882
Uric acid (μmo/L)	432.72 ± 139.25	410.53 ± 104.66	0.439
CO2-CP (mmol/L)	18.13 ± 3.37	19.33 ± 3.63	0.144
Serum sodium (mmol/L)	139.59 ± 3.00	138.77 ± 3.21	0.262
Serum potassium (mmol/L)	4.63 ± 0.57	4.50 ± 0.73	0.411
Corrected serum calcium (mmol/L)	2.08 ± 0.24	2.07 ± 0.31	0.867
Serum magnesium (mmol/L)	1.02 ± 0.20	0.96 ± 0.24	0.230
Serum phosphorous (mmol/L)	1.93 ± 0.43	1.87 ± 0.57	0.591
iPTH (pmol/L)	35.57 ± 27.84	48.70 ± 33.52	0.095
NT-pro-BNP (ng/L)	6702.76 ± 11395.45	7323.04 ± 10968.84	0.721

eGFR: estimated glomerular filtration rate; CO₂-CP: carbon dioxide combining power; iPTH: intact parathyroid hormone; NT-pro-BNP: N-terminal pro-brain natriuretic peptide.

Corrected serum calcium = serum calcium(mmol/L)+(40 albumin(g/L))*0.02.

Table 3. Self-comparison of laboratory parameters before and after USPD within groups.

Characteristics	A-MPD			MPD
	Before	After	p Value	Before	After	p Value
Hemoglobin (g/L)	91.42 ± 17.13	91.58 ± 15.47	0.936	83.66 ± 15.22	84.52 ± 12.26	0.634
Albumin (g/L)	40.47 ± 4.31	37.63 ± 4.07	0.000*	40.01 ± 4.59	36.92 ± 4.61	0.000*
Blood urea nitrogen (mmol/L)	33.06 ± 10.55	23.63 ± 7.55	0.000*	29.55 ± 8.67	25.07 ± 7.29	0.000*
Creatinine (μmo/L)	894.71 ± 234.13	786.94 ± 214.82	0.000*	810.45 ± 188.95	747.93 ± 180.95	0.000*
Uric acid (μmo/L)	439.13 ± 145.29	377.06 ± 103.82	0.015*	415.48 ± 103.69	397.79 ± 99.58	0.309
CO2-CP (mmol/L)	18.20 ± 3.53	23.08 ± 2.95	0.000*	19.19 ± 3.56	21.21 ± 2.91	0.013*
Serum sodium (mmol/L)	139.62 ± 2.91	139.99 ± 3.03	0.459	138.81 ± 3.35	139.58 ± 1.79	0.233
Serum potassium (mmol/L)	4.67 ± 0.59	4.10 ± 0.52	0.000*	4.49 ± 0.67	4.24 ± 0.48	0.023*
Corrected serum calcium (mmol/L)	2.07 ± 0.25	2.21 ± 0.18	0.028*	2.04 ± 0.24	2.16 ± 0.18	0.036*
Serum magnesium (mmol/L)	1.03 ± 0.20	0.93 ± 0.12	0.000*	0.98 ± 0.26	0.91 ± 0.176	0.007*
Serum phosphorous (mmol/L)	1.94 ± 0.45	1.92 ± 0.36	0.812	1.79 ± 0.47	1.85 ± 0.50	0.509
iPTH (pmol/L)	34.31 ± 19.96	23.67 ± 14.38	0.043*	48.91 ± 42.55	33.33 ± 27.33	0.010*
NT-pro-BNP (ng/L)	3425.56 ± 5480.51	4498.22 ± 9411.77	0.503	7178.91 ± 10168.68	4030.82 ± 4575.65	0.109

CO₂-CP: carbon dioxide combining power; iPTH: intact parathyroid hormone; NT-pro-BNP,:N-terminal pro-brain natriuretic peptide. Corrected serum calcium = serum calcium (mmol/L)+(40 albumin(g/L))*0.02.

Table 4. Comparison of the difference of laboratory parameters before and after USPD between the two groups.

Characteristics	A-MPD Δ1	MPD Δ2	p Value
Hemoglobin (g/L)	–0.16 ± 11.15	–0.86 ± 9.65	0.796
Albumin (g/L)	2.84 ± 3.25	3.09 ± 3.26	0.766
Blood urea nitrogen (mmol/L)	9.43 ± 8.27	4.48 ± 5.88	0.010*
Creatinine (μmo/L)	107.77 ± 95.84	62.52 ± 54.58	0.030*
Uric acid (μmo/L)	62.07 ± 133.38	17.69 ± 91.96	0.142
CO2-CP (mmol/L)	–4.89 ± 4.90	–2.02 ± 4.12	0.018*
Serum sodium (mmol/L)	–0.38 ± 2.80	–0.77 ± 3.41	0.625
Serum potassium (mmol/L)	0.57 ± 0.62	0.25 ± 0.56	0.039*
Corrected serum calcium (mmol/L)	–0.14 ± 0.15	–0.12 ± 0.19	0.600
Serum magnesium (mmol/L)	0.11 ± 0.13	0.08 ± 0.14	0.337
Serum phosphorous (mmol/L)	0.02 ± 0.46	–0.06 ± 0.49	0.511
iPTH (pmol/L)	10.64 ± 9.64	15.59 ± 18.48	0.549
NT-pro-BNP (ng/L)	–1072.67 ± 4589.07	3148.09 ± 5930.94	0.098

CO₂-CP: carbon dioxide combining power; iPTH: intact parathyroid hormone; NT-pro-BNP: N-terminal pro-brain natriuretic peptide.

Corrected serum calcium = serum calcium(mmol/L)+(40 albumin(g/L))*0.02.

Δ1 and Δ2, the value for the difference before and after USPD (before USPD – 5 days after USPD) in A-MPD group and MPD group, respectively.

Table 5. PD-related complications during 5-day USPD treatment.

Complications, n (%)	A-MPD	MPD	p Value
Total	9 (25.00%)	12 (31.58%)	0.530
Leakage	4 (11.11%)	5 (13.16%)	1.000
PDC malfunction	4 (11.11%)	5 (13.16%)	1.000
Catheter displacement	0 (0.00%)	1 (2.63%)	1.000
Catheter blockage	3 (8.33%)	4 (10.53%)	1.000
Omental encapsulation	1 (2.78%)	0 (0.00%)	0.486
Peritonitis	1 (2.78%)	0 (0.00%)	0.486
Catheter-related infection	0 (0.00%)	0 (0.00%)	–
Inguinal hernia	0 (0.00%)	2 (5.26%)	0.494

PDC: peritoneal dialysis catheter.

Table 6. Reasons of quitting the study.

Reasons, n (%)	A-MPD	MPD	p Value
Total	5 (13.89%)	9 (23.68%)	0.282
Leakage	2 (5.56%)	3 (7.89%)	1.000
PDC malfunction	2 (5.56%)	4 (10.53%)	0.675
Catheter displacement	0 (0.00%)	1 (2.63%)	1.000
Catheter blockage	1 (2.78%)	3 (7.89%)	0.615
Omental encapsulation	1 (2.78%)	0 (0.00%)	0.486
Peritonitis	1 (2.78%)	0 (0.00%)	0.486
Catheter-related infection	0 (0.00%)	0 (0.00%)	–
Inguinal hernia	0 (0.00%)	2 (5.26%)	0.494

PDC: peritoneal dialysis catheter.

Table 7. The time expenditure of PD nurses and test score of patients.

Variable	A-MPD	MPD	p Value
Operation time (minutes)	248.45 ± 6.20	256.86 ± 11.70	0.001*
Score of operation exams	183.63 ± 15.83	167.59 ± 20.32	0.002*

Table 8. Technique and patient survival during 6 months.

	A-MPD	MPD	p Value
PD technical survival rate (%)	96.77%	89.66%	0.346
Transfer to HD, n (%)	1 (3.23%)	0 (0.00%)	1.000
Combined with HD, n (%)	0 (0.00%)	0 (0.00%)	–
Transfer to renal transplantation, n (%)	0 (0.00%)	1 (3.45%)	0.483
Death n (%)	0 (0.00%)	0 (0.00%)	–
Total number of follow-up, n	31	29	–
Losing to follow-up, n (%)	0 (0.00%)	2 (6.90%)	0.229

Table

1. Clean and dry the hands; clean the operating board.	5 points
2. Gather the required supplies: the solution bags, face-mask, mini-cap package, clamps, basin, hand-sanitizer, etc.	5 points
3. Wear a face-mask and wash hands with routine steps.	5 points
4. Check the expiration date, solution amount and concentration on the package of the twin-bag fluid. Open the outer package, take out the twin-bag fluid, check for leaks. Make sure the pull ring and pipelines are in place.	10 points
5. Hang the twin-bag fluid, separate the lines, and place the drain bag in the basin on the ground.	5 points
6. Close the filling line and drain line respectively with two clamps.	5 points
7. Expose the transfer set and check the twist clamp is closed.	10 points
8. Remove the pull ring from the twin-bag connector, remove the mini-cap from the transfer set.	10 points
9. Immediately attach the twin-bag connector to the transfer set by twist the twin-bag connector, avoiding crossing over when making connections.	10 points
10. Remove the clamp on the draining line.	10 points
11. Open the twist-clamp on the transfer set a half turn and start to drain, observing flow speed of the drained fluid.	10 points
12. After draining, place the clamp on the draining line and close it. Close the twist clamp on the transfer set.	10 points
13. Open the switch between the fluid and filling line.	10 points
14. Open the clamps on the filling line and the draining line for 5 s, flushing fresh fluids into the drain bag.	10 points
15. Close the clamp on the drainage line.	10 points
16. Open the twist-clamp on the transfer set a half turn to fill.	10 points
17. After filling, close the clamp on the filling line.	10 points
18. Close the twist-clamp on the transfer set.	10 points
19. Check the package of mini cap. Open the package and check whether the cap is infiltrated with iodophor solution.	5 points
20. Check the twist camp on the transfer set is closed	5 points
21. Unscrew the twin-bag connector from the transfer set, keeping the transfer set in the hand.	10 points
22. Apply a new mini-cap to the transfer set immediately, avoiding crossing over.	10 points
23. Check the drain fluid for clarity and color.	5 points
24. Weigh the drain bag and record the ultrafiltration volume.	5 points
25. Dispose the drainage fluids and disposable items.	5 points

The total score is 200 points. The patient is considered to be qualified if he or she got more than 120 points.

Data availability statement

The datasets used and analyzed during the current study are available from the corresponding author upon reasonable request.