28 April 2026 : Clinical Research
A Dynamic Online Nomogram for Predicting Postoperative Acute Kidney Injury After Sleeve Gastrectomy
Sainan Li BE 1,2, Chengxiang Liu
C 1*, Chen Zhu B 1, Juan Zhou D 1, Miao Zhang F 3, Hong Chen E 1, Ye Zhang G 4, Zengxia Liu A 2
DOI: 10.12659/MSM.951259
Med Sci Monit 2026; 32:e951259
Table 1 Demographic and clinical characteristics of the study population stratified by AKI status.
| Clinical characteristic | All patients (N=1386) | No AKI (N=1308) | AKI (N=78) | P value | SMD | Missing, n (%) | |
|---|---|---|---|---|---|---|---|
| Age, year, (median [IQR]) | 31.00 [26.00, 36.00] | 31.00 [26.00, 36.00] | 30.50 [27.00, 37.75] | 0.623 | 0.073 | 0 (0) | |
| Gender, n (%) | Male | 380 (27.4) | 350 (26.8) | 30 (38.5) | 0.252 | 0 (0) | |
| Female | 1006 (72.6) | 958 (73.2) | 48 (61.5) | ||||
| Height, m, (median [IQR]) | 165.00 [160.00, 171.00] | 165.00 [160.00, 171.00] | 166.50 [160.00, 172.25] | 0.561 | 0.061 | 483 (34.8) | |
| Weight, kg, (median [IQR]) | 106.00 [93.00, 121.00] | 105.50 [93.00, 120.00] | 110.00 [94.50, 129.00] | 0.148 | 0.211 | 464 (33.5) | |
| BMI, kg/m (median [IQR]) | 38.12 [34.72, 43.05] | 38.06 [34.72, 42.78] | 39.99 [35.48, 46.02] | 0.081 | 0.202 | 483 (34.8) | |
| Smoking, n (%) | No | 1297 (95.6) | 1227 (96.0) | 70 (89.7) | 0.245 | 30 (2.2) | |
| Yes | 59 (4.4) | 51 (4.0) | 8 (10.3) | ||||
| Drinking, n (%) | No | 1253 (96.2) | 1183 (96.4) | 70 (93.3) | 0.294 | 0.140 | 84 (6.1) |
| Yes | 49 (3.8) | 44 (3.6) | 5 (6.7) | ||||
| ASA grade, n (%) | I~II | 1129 (81.5) | 1074(82.1) | 55 (70.5) | 0.298 | 0 (0) | |
| III~IV | 257 (18.6) | 234 (17.9) | 23 (29.5) | ||||
| History of hypertension, n (%) | No | 1240 (89.5) | 1177 (90.0) | 63 (80.8) | 0.263 | 0 (0) | |
| Yes | 146 (10.5) | 131 (10.0) | 15 (19.2) | ||||
| History of diabetes mellitus, n (%) | No | 1266 (91.3) | 1195 (91.4) | 71 (91.0) | 1.000 | 0.012 | 0 (0) |
| Yes | 120 (8.7) | 113 (8.6) | 7 (9.0) | ||||
| Anesthesia duration, min, (median [IQR]) | 108.00 [95.00, 125.00] | 108.00 [95.00, 125.00] | 110.50 [95.50, 127.25] | 0.364 | 0.087 | 0 (0) | |
| Preoperative laboratory parameters | |||||||
| Albumin, g/L, (median [IQR]) | 40.70 [38.80, 42.70] | 40.70 [38.80, 42.70] | 40.65 [39.02, 42.25] | 0.528 | 0.100 | 38 (2.7) | |
| Creatinine, μmol/L, (median [IQR]) | 48.00 [42.00, 57.00] | 49.00 [43.00, 57.00] | 46.00 [39.00, 53.75] | 0.164 | 38 (2.7) | ||
| eGFR, mL/min/1.73 m, (median [IQR]) | 127.72 [120.93, 134.57] | 127.39 [120.75, 134.20] | 130.02 [126.47, 138.18] | 0.430 | 56 (4) | ||
| BUN, mmol/L, (median [IQR]) | 4.87 [4.13, 5.66] | 4.88 [4.13, 5.67] | 4.58 [3.95, 5.33] | 0.066 | 0.175 | 38 (2.7) | |
| Potassium, mmol/L, (median [IQR]) | 3.95 [3.77, 4.13] | 3.96 [3.77, 4.13] | 3.93 [3.72, 4.07] | 0.327 | 0.101 | 48 (3.5) | |
| Sodium, mmol/L, (median [IQR]) | 140.10 [138.70, 141.40] | 140.10 [138.70, 141.40] | 140.10 [139.30, 141.30] | 0.579 | 0.105 | 48 (3.5) | |
| Calcium, mmol/L, (median [IQR]) | 1.60 [1.47, 2.21] | 1.60 [1.47, 2.21] | 1.58 [1.43, 1.89] | 0.093 | 0.150 | 42 (3) | |
| Chloride, mmol/L, (median [IQR]) | 104.60 [102.90, 105.90] | 104.60 [102.90, 105.90] | 104.20 [103.30, 105.80] | 0.582 | 0.070 | 48 (3.5) | |
| Fasting glucose, mmol/L, (median [IQR]) | 5.36 [4.80, 6.57] | 5.35 [4.80, 6.55] | 5.50 [4.83, 6.88] | 0.598 | 0.020 | 47 (3.4) | |
| Hemoglobin A1c, %, (median [IQR]) | 5.90 [5.50, 6.60] | 5.90 [5.50, 6.60] | 5.80 [5.68, 6.90] | 0.418 | 0.040 | 92 (6.6) | |
| Hemoglobin, g/L, (median [IQR]) | 138.00 [128.00, 149.00] | 137.00 [127.00, 149.00] | 143.50 [134.75, 153.00] | 0.458 | 226 (16.3) | ||
| Neutrophils, ×10/L, (median [IQR]) | 4.92 [3.97, 6.07] | 4.87 [3.96, 6.06] | 5.42 [4.08, 6.34] | 0.141 | 0.196 | 226 (16.3) | |
| White blood cell count, ×10/L, (median [IQR]) | 8.36 [7.09, 9.77] | 8.32 [7.07, 9.75] | 9.08 [7.53, 10.01] | 0.058 | 0.246 | 226 (16.3) | |
| Platelet Count, ×10/L, (median [IQR]) | 282.00 [235.00, 326.00] | 282.00 [234.00, 325.25] | 279.00 [238.25, 327.50] | 0.651 | 0.048 | 226 (16.3) | |
| C-reactive protein (CRP), mg/L, (median [IQR]) | 6.00 [3.20, 9.60] | 6.00 [3.30, 9.60] | 4.60 [2.90, 8.30] | 0.268 | 0.192 | 662 (47.8) | |
| Urine specific gravity, (median [IQR]) | 1.02 [1.02, 1.02] | 1.02 [1.02, 1.03] | 1.02 [1.01, 1.02] | 0.059 | 0.223 | 95 (6.9) | |
| Proteinuria, n (%) | Yes | 212(15.30) | 192 (14.7) | 20 (25.6) | 0 (0) | ||
| No | 1174(84.7) | 1116 (85.3) | 58 (74.4) | ||||
| Urinary red blood cells, n (%) | Yes | 329 (23.74) | 309 (23.6) | 20 (25.6) | 0.787 | 0.047 | 0 (0) |
| No | 1057(76.26) | 999 (76.4) | 58 (74.4) | ||||
| Intraoperative parameters | |||||||
| Intraoperative vasopressor use (%) (Phenylephrine/norepinephrine/dopamine/dobutamine) | No | 1316 (94.9) | 1243 (95.0) | 73 (93.6) | 0.812 | 0.076 | 0 (0) |
| Yes | 70 (5.1) | 65 (5.0) | 5 (6.4) | ||||
| Blood loss, ml, (median [IQR]) | 0.00 [0.00, 0.00] | 0.00 [0.00, 0.00] | 0.00 [0.00, 0.00] | 0.438 | 0.081 | 0 (0) | |
| Total Infusion Volume, ml, (median [IQR]) | 600.00 [400.00, 800.00] | 600.00 [400.00, 800.00] | 500.00 [0.00, 700.00] | 0.242 | 0 (0) | ||
| Intraoperative urine volume, ml, (median [IQR]) | 0.00 [0.00, 0.00] | 0.00 [0.00, 0.00] | 0.00 [0.00, 0.00] | 0.346 | 0 (0) | ||
| Crystalloid Solution, ml, (median [IQR]) | 500.00 [350.00, 600.00] | 500.00 [350.00, 600.00] | 500.00 [75.00, 600.00] | 0.113 | 0.212 | 0 (0) | |
| Plasma substitute, ml, (median [IQR]) | 0.00 [0.00, 0.00] | 0.00 [0.00, 0.00] | 0.00 [0.00, 0.00] | 0.816 | 0.007 | 0 (0) | |
| Mean_SBP (median [IQR]) | 128.86 [119.81, 138.99] | 129.10 [120.25, 139.26] | 125.18 [114.99, 134.89] | 0.293 | 0 (0) | ||
| SD_SBP (median [IQR]) | 20.15 [16.22, 25.06] | 20.14 [16.12, 24.95] | 20.31 [17.58, 26.89] | 0.084 | 0.213 | 0 (0) | |
| CV_SBP (median [IQR]) | 15.74 [12.69, 19.33] | 15.70 [12.59, 19.14] | 16.44 [13.73, 21.80] | 0.294 | 0 (0) | ||
| AKI – acute kidney injury; IQR – interquartile range; BMI – body mass index; ASA – American Society of Anesthesiologists physical status classification; eGFR – estimated glomerular filtration rate; BUN – blood urea nitrogen; HbA1c – hemoglobin A1c; CRP – C-reactive protein; WBC – white blood cell count; SBP – systolic blood pressure; SD_SBP – standard deviation of systolic blood pressure; CV_SBP – coefficient of variation of systolic blood pressure. Data are presented as median [IQR] for continuous variables and number (percentage) for categorical variables. P-values are derived from the chi-square test, Mann-Whitney U test, or Fisher’s exact test, as appropriate. SMD represents the standardized mean difference, with values 0.5 indicating negligible, small, moderate, and large differences, respectively. Baseline characteristics are reported based on available data. The proportion of missing values for individual variables ranged from 0% to 47.8%. Most demographic, comorbidity, and intraoperative variables had minimal missing data ( | |||||||