Risk factors for overall postoperative complications in elderly patients undergoing gastrointestinal surgeries: a multicenter observational study

doi:10.12122/j.issn.1673-4254.2025.04.08

Abstract

Abstract:

Objective To investigate the risk factors of overall postoperative complications in elderly patients undergoing gastrointestinal surgeries. Methods This study was conducted among a total of 1388 elderly patients, who underwent elective gastrointestinal surgeries at 17 centers across China between April, 2020 and April, 2022. The primary outcome was the incidence of postoperative complications within 30 days, including procedure-related, neuropsychiatric, respiratory, cardiovascular, and gastrointestinal complications as well as acute kidney injury. Baseline characteristics, preoperative psychological and functional status, intraoperative anesthesia and surgical factors, intraoperative medication, use of nerve block, and postoperative analgesia methods were compared between the patients experiencing one or more postoperative complications and those without complications. Univariate and multivariate logistic regression analyses were performed to identify the independent risk factors for postoperative complications. The relationship between postoperative acute pain and each type of complication were explored. Results The incidence of overall postoperative complications was 50.8% (705/1388) in these patients. Multivariate analysis showed that age (OR: 1.026; 95% CI: 1.006-1.046), prognostic nutritional index (OR: 0.998; 95% CI: 0.997-1.000), preoperative EuroQol-5 dimensions score (OR: 0.094; 95% CI: 0.018-0.500), blood loss (OR: 1.002; 95% CI: 1.001-1.003), and acute postoperative pain (OR: 1.308; 95% CI: 1.033-1.657) were significantly associated with the occurrence of postoperative complications. Specifically, patients experiencing severe postoperative pain had a significantly higher incidence of neuropsychiatric (27.2% vs 19.8%), procedure-related (17.3% vs 10.2%), and cardiovascular complications (3.6% vs 1.7%). Conclusion An advanced age, a low preoperative nutritional index, a poor quality of life score, a greater volume of intraoperative blood loss, and acute postoperative pain are independent risk factors for postoperative complications in elderly patients undergoing gastrointestinal surgeries. There is a significant association between acute postoperative pain and multi-system complications.

Key words: gastrointestinal surgery, elderly patients, risk factors, postoperative complications, pain

Xuecai LÜ, Yanhong LIU, Shiyi HAN, Haoyun ZHANG, Aisheng HOU, Zhikang ZHOU, Likai SHI, Jie GAO, Jiangbei CAO, Hong ZHANG, Weidong MI. Risk factors for overall postoperative complications in elderly patients undergoing gastrointestinal surgeries: a multicenter observational study[J]. Journal of Southern Medical University, 2025, 45(4): 736-743.

Figures/Tables 5

References 40

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Parameter	Total (n=1388)	No postoperative complications (n=683)	Have postoperative complications (n=705)	OR (95% CI)	P
Age (year)	71.0 (68.0, 76.0)	71.0 (68.0, 75.0)	72.0 (68.0, 76.0)	1.028 (1.008-1.048)	0.005
Gender [n (%)]				1.002 (0.804-1.250)	0.984
Female	906 (65.3%)	446 (65.3%)	460 (65.2%)
Male	482 (34.7%)	237 (34.7%)	245 (34.8%)
Height (cm)	164.6 (160.0, 170.0)	165.0 (160.0, 170.0)	164.6 (160.0, 170.0)	1.001 (0.998-1.014)	0.884
Weight (kg)	63.7 (57.0, 70.0)	63.7 (57.0, 70.0)	63.7 (57.0, 70.0)	0.997 (0.987-1.007)	0.541
BMI (kg/m²)	23.5 (21.3, 25.4)	23.5 (21.3, 25.6)	23.5 (21.4, 25.1)	0.985 (0.953-1.018)	0.374
ASA				1.262 (1.001-1.590)	0.049
Ⅰ-Ⅱ	978 (70.5%)	498 (72.9%)	480 (68.1%)
Ⅲ-Ⅴ	410 (29.5%)	185 (27.1%)	225 (31.9%)
Medical History [n (%)]
Hypertension	605 (43.6%)	289 (42.3%)	316 (44.8%)	1.107 (0.896-1.369)	0.346
Diabetes	290 (20.9%)	131 (19.2%)	159 (22.6%)	1.227 (0.946-1.591)	0.123
Coronary heart disease	188 (13.5%)	88 (12.9%)	100 (14.2%)	1.118 (0.821-1.521)	0.479
Cerebrovascular disease	79 (5.7%)	31 (4.5%)	48 (6.8%)	1.537 (0.966-2.445)	0.070
Respiratory disease	55 (4.0%)	21 (3.1%)	34 (4.8%)	1.597 (0.917-2.781)	0.098
Kidney disease	66 (4.8%)	29 (4.2%)	37 (5.2%)	1.249 (0.759-2.055)	0.381
Smoking	432 (31.1%)	218 (31.9%)	214 (30.4%)	0.930 (0.741-1.167)	0.529
Alcohol consumption	410 (29.5%)	207 (30.3%)	203 (28.8%)	0.930 (0.738-1.171)	0.537
Preoperative chronic pain	255 (18.4%)	106 (15.5%)	149 (21.1%)	1.459 (1.108-1.920)	0.007
Preoperative nutritional support	163 (11.7%)	71 (10.4%)	92 (13.0%)	1.294 (0.931-1.798)	0.125
Preoperative psychological and functional status
Frailty [n (%)]	35 (2.5%)	14 (2.0%)	21 (3.0%)	1.467 (0.740-2.909)	0.272
EQ-5D	1.0 (0.9, 1.0)	1.0 (0.9, 1.0)	0.9 (0.9, 1.0)	0.073 (0.014-0.380)	0.002
EQ-VAS	76.0 (70.0, 80.0)	76.0 (75.0, 80.0)	76.0 (70.0, 80.0)	0.992 (0.984-1.000)	0.060
MET				0.719 (0.483-1.070)	0.104
<4	108 (7.8%)	45 (6.6%)	63 (8.9%)
≥4	1280 (92.2%)	638 (93.4%)	642 (91.1%)
Preoperative laboratory test
PNI	42.3 (37.4, 126.3)	42.9 (38.1, 139.0)	41.7 (36.8, 89.5)	0.998 (0.997-1.000)	0.043
Albumin (g/L)	39.0 (36.2, 41.2)	39.0 (36.5, 41.0)	39.0 (36.0, 41.3)	0.995 (0.984-1.006)	0.401
Hemoglobin (g/L)	120.6 (108.0, 134.0)	122.0 (109.0, 135.0)	120.3 (106.0, 134.0)	0.996 (0.991-1.001)	0.120
Glucose (µmol/L)	5.5 (4.8, 5.8)	5.5 (4.8, 5.8)	5.5 (4.8, 5.8)	1.021 (0.956-1.091)	0.531
Intraoperative medication
Consumption of opioids (mg)	143.5 (50.0, 232.9)	140.0 (50.0, 230.0)	148.0 (45.0, 240.0)	1.000 (0.999-1.001)	0.796
NSAIDs [n (%)]	529 (38.1%)	264 (38.7%)	265 (37.6%)	0.956 (0.770-1.187)	0.683
Dexmedetomidine [n (%)]	333 (24.0%)	174 (25.5%)	159 (22.6%)	0.852 (0.666-1.090)	0.203
Surgical/Anesthetic parameters
Blood loss (mL)	100.0 (50.0, 128.7)	60.0 (50.0, 128.7)	100.0 (50.0, 128.7)	1.002 (1.001-1.003)	<0.001
Duration of surgery (min)	191.5 (143.3, 240.0)	185.0 (136.0, 230.0)	198.4 (150.0, 250.0)	1.002 (1.001-1.003)	0.002
Location of surgery [n (%)]				0.930 (0.746-1.160)	0.521
Gastrectomy	481 (34.7%)	231 (33.8%)	250 (35.5%)
Enterectomy	907 (65.3%)	452 (66.2%)	455 (64.5%)
Type of surgery [n (%)]				1.194 (0.934-1.527)	0.157
Open	1050 (75.6%)	528 (77.3%)	522 (74.0%)
Minimally invasive	338 (24.4%)	155 (22.7%)	183 (26.0%)
Anesthesia methods [n (%)]				0.843 (0.621-1.145)	0.275
GA	1197 (86.2%)	582 (85.2%)	615 (87.2%)
GA+RA	191 (13.8%)	101 (14.8%)	90 (12.8%)
Postoperative analgesia methods [n (%)]					0.191
No	480 (34.6%)	286 (36.5%)	194 (34.6%)
Intravenous analgesia	784 (56.5%)	432 (55.2%)	352 (56.5%)	1.201 (0.954, 1.512)
Others	124 (8.9%)	65 (8.3%)	59 (9.8%)	1.338 (0.900, 1.990)
Postoperative acute pain				1.359 (1.079-1.712)	0.009
Mild to moderate pain	973 (70.1%)	501 (73.4%)	472 (67.0%)
Severe pain	415 (29.9%)	182 (26.6%)	233 (33.0%)

Parameter	Total (n=1388)	No postoperative complications (n=683)	Have postoperative complications (n=705)	OR (95% CI)	P
Age (year)	71.0 (68.0, 76.0)	71.0 (68.0, 75.0)	72.0 (68.0, 76.0)	1.028 (1.008-1.048)	0.005
Gender [n (%)]				1.002 (0.804-1.250)	0.984
Female	906 (65.3%)	446 (65.3%)	460 (65.2%)
Male	482 (34.7%)	237 (34.7%)	245 (34.8%)
Height (cm)	164.6 (160.0, 170.0)	165.0 (160.0, 170.0)	164.6 (160.0, 170.0)	1.001 (0.998-1.014)	0.884
Weight (kg)	63.7 (57.0, 70.0)	63.7 (57.0, 70.0)	63.7 (57.0, 70.0)	0.997 (0.987-1.007)	0.541
BMI (kg/m²)	23.5 (21.3, 25.4)	23.5 (21.3, 25.6)	23.5 (21.4, 25.1)	0.985 (0.953-1.018)	0.374
ASA				1.262 (1.001-1.590)	0.049
Ⅰ-Ⅱ	978 (70.5%)	498 (72.9%)	480 (68.1%)
Ⅲ-Ⅴ	410 (29.5%)	185 (27.1%)	225 (31.9%)
Medical History [n (%)]
Hypertension	605 (43.6%)	289 (42.3%)	316 (44.8%)	1.107 (0.896-1.369)	0.346
Diabetes	290 (20.9%)	131 (19.2%)	159 (22.6%)	1.227 (0.946-1.591)	0.123
Coronary heart disease	188 (13.5%)	88 (12.9%)	100 (14.2%)	1.118 (0.821-1.521)	0.479
Cerebrovascular disease	79 (5.7%)	31 (4.5%)	48 (6.8%)	1.537 (0.966-2.445)	0.070
Respiratory disease	55 (4.0%)	21 (3.1%)	34 (4.8%)	1.597 (0.917-2.781)	0.098
Kidney disease	66 (4.8%)	29 (4.2%)	37 (5.2%)	1.249 (0.759-2.055)	0.381
Smoking	432 (31.1%)	218 (31.9%)	214 (30.4%)	0.930 (0.741-1.167)	0.529
Alcohol consumption	410 (29.5%)	207 (30.3%)	203 (28.8%)	0.930 (0.738-1.171)	0.537
Preoperative chronic pain	255 (18.4%)	106 (15.5%)	149 (21.1%)	1.459 (1.108-1.920)	0.007
Preoperative nutritional support	163 (11.7%)	71 (10.4%)	92 (13.0%)	1.294 (0.931-1.798)	0.125
Preoperative psychological and functional status
Frailty [n (%)]	35 (2.5%)	14 (2.0%)	21 (3.0%)	1.467 (0.740-2.909)	0.272
EQ-5D	1.0 (0.9, 1.0)	1.0 (0.9, 1.0)	0.9 (0.9, 1.0)	0.073 (0.014-0.380)	0.002
EQ-VAS	76.0 (70.0, 80.0)	76.0 (75.0, 80.0)	76.0 (70.0, 80.0)	0.992 (0.984-1.000)	0.060
MET				0.719 (0.483-1.070)	0.104
<4	108 (7.8%)	45 (6.6%)	63 (8.9%)
≥4	1280 (92.2%)	638 (93.4%)	642 (91.1%)
Preoperative laboratory test
PNI	42.3 (37.4, 126.3)	42.9 (38.1, 139.0)	41.7 (36.8, 89.5)	0.998 (0.997-1.000)	0.043
Albumin (g/L)	39.0 (36.2, 41.2)	39.0 (36.5, 41.0)	39.0 (36.0, 41.3)	0.995 (0.984-1.006)	0.401
Hemoglobin (g/L)	120.6 (108.0, 134.0)	122.0 (109.0, 135.0)	120.3 (106.0, 134.0)	0.996 (0.991-1.001)	0.120
Glucose (µmol/L)	5.5 (4.8, 5.8)	5.5 (4.8, 5.8)	5.5 (4.8, 5.8)	1.021 (0.956-1.091)	0.531
Intraoperative medication
Consumption of opioids (mg)	143.5 (50.0, 232.9)	140.0 (50.0, 230.0)	148.0 (45.0, 240.0)	1.000 (0.999-1.001)	0.796
NSAIDs [n (%)]	529 (38.1%)	264 (38.7%)	265 (37.6%)	0.956 (0.770-1.187)	0.683
Dexmedetomidine [n (%)]	333 (24.0%)	174 (25.5%)	159 (22.6%)	0.852 (0.666-1.090)	0.203
Surgical/Anesthetic parameters
Blood loss (mL)	100.0 (50.0, 128.7)	60.0 (50.0, 128.7)	100.0 (50.0, 128.7)	1.002 (1.001-1.003)	<0.001
Duration of surgery (min)	191.5 (143.3, 240.0)	185.0 (136.0, 230.0)	198.4 (150.0, 250.0)	1.002 (1.001-1.003)	0.002
Location of surgery [n (%)]				0.930 (0.746-1.160)	0.521
Gastrectomy	481 (34.7%)	231 (33.8%)	250 (35.5%)
Enterectomy	907 (65.3%)	452 (66.2%)	455 (64.5%)
Type of surgery [n (%)]				1.194 (0.934-1.527)	0.157
Open	1050 (75.6%)	528 (77.3%)	522 (74.0%)
Minimally invasive	338 (24.4%)	155 (22.7%)	183 (26.0%)
Anesthesia methods [n (%)]				0.843 (0.621-1.145)	0.275
GA	1197 (86.2%)	582 (85.2%)	615 (87.2%)
GA+RA	191 (13.8%)	101 (14.8%)	90 (12.8%)
Postoperative analgesia methods [n (%)]					0.191
No	480 (34.6%)	286 (36.5%)	194 (34.6%)
Intravenous analgesia	784 (56.5%)	432 (55.2%)	352 (56.5%)	1.201 (0.954, 1.512)
Others	124 (8.9%)	65 (8.3%)	59 (9.8%)	1.338 (0.900, 1.990)
Postoperative acute pain				1.359 (1.079-1.712)	0.009
Mild to moderate pain	973 (70.1%)	501 (73.4%)	472 (67.0%)
Severe pain	415 (29.9%)	182 (26.6%)	233 (33.0%)

Postoperative complications	n (%)
Overall complications	705 (50.8%)
Respiratory complications	451 (32.5%)
Pulmonary infection	341 (24.6%)
Respiratory failure	7 (0.5%)
Pleural effusion	60 (4.3%)
Atelectasis	19 (1.4%)
Pneumothorax	20 (1.4%)
Bronchiostenosis	3 (0.2%)
Aspiration pneumonia	2 (0.1%)
Pulmonary embolism	3 (0.2%)
Pulmonary edema	2 (0.1%)
Neuropsychiatric complications	306 (22.0%)
Stroke	12 (0.9%)
Delirium	231 (16.6%)
Depression	91 (6.6%)
Procedure-related complications	171 (12.3%)
Surgical site infection	143 (10.3%)
Anastomotic leakage	47 (3.4%)
Ileus	21 (1.5%)
Chylous fistula	2 (0.1%)
Acute Kidney Injury	53 (3.8%)
Gastrointestinal complications	32 (2.3%)
Gastroparesis	9 (0.6%)
Diarrhea	16 (1.2%)
Gastrointestinal bleeding	10 (0.7%)
Cardiovascular complications	32 (2.3%)
Myocardial infarction	4 (0.3%)
Heart failure	3 (0.2%)
Angina	1 (0.1%)
Arrhythmia	25 (1.8%)
Cardiac arrest or death	2 (0.1%)

Postoperative complications	n (%)
Overall complications	705 (50.8%)
Respiratory complications	451 (32.5%)
Pulmonary infection	341 (24.6%)
Respiratory failure	7 (0.5%)
Pleural effusion	60 (4.3%)
Atelectasis	19 (1.4%)
Pneumothorax	20 (1.4%)
Bronchiostenosis	3 (0.2%)
Aspiration pneumonia	2 (0.1%)
Pulmonary embolism	3 (0.2%)
Pulmonary edema	2 (0.1%)
Neuropsychiatric complications	306 (22.0%)
Stroke	12 (0.9%)
Delirium	231 (16.6%)
Depression	91 (6.6%)
Procedure-related complications	171 (12.3%)
Surgical site infection	143 (10.3%)
Anastomotic leakage	47 (3.4%)
Ileus	21 (1.5%)
Chylous fistula	2 (0.1%)
Acute Kidney Injury	53 (3.8%)
Gastrointestinal complications	32 (2.3%)
Gastroparesis	9 (0.6%)
Diarrhea	16 (1.2%)
Gastrointestinal bleeding	10 (0.7%)
Cardiovascular complications	32 (2.3%)
Myocardial infarction	4 (0.3%)
Heart failure	3 (0.2%)
Angina	1 (0.1%)
Arrhythmia	25 (1.8%)
Cardiac arrest or death	2 (0.1%)

Factor	b	SE	Wald	OR (95% CI)	P
Age (year)	0.026	0.010	6.710	1.026(1.006-1.046)	0.010
Preoperative PNI	-0.002	0.001	4.352	0.998(0.997-1.000)	0.037
Preoperative EQ-5D	-2.369	0.855	7.681	0.094(0.018-0.500)	0.006
Blood loss (mL)	0.002	0.000	21.013	1.002(1.001-1.003)	<0.001
Postoperative acute pain (Mild to moderate pain/severe pain)	0.269	0.121	4.959	1.308(1.033-1.657)	0.026