Intraoperative complications in kidney tumor surgery: critical grading for the European Association of Urology intraoperative adverse incident classification

Figures & data

Table 1. Clinical characteristics.

	Radical nephrectomy (n = 749)	Partial nephrectomy (n = 531)
Variable	N(%)	N(%)	p-Value*
Sex
Male	418 (55.8)	345 (65.0)
Female	331 (44.2)	186 (35.0)	<0.001
Age, median (IQR)	68 (60–75)	66 (57–72)	<0.001
BMI, median (IQR)	26.7 (24.0–30.7)	27.8 (25.9–31.0)	0.009
Missing	2 (0.3)	3 (0.6)
CCI
0	469 (62.6)	311 (58.6)
1	105 (14.0)	70 (13.2)
≥2	175 (23.4)	150 (28.2)	0.048
ECOG
0–1	596 (79.6)	455 (85.7)
≥2	122 (16.3)	50 (9.4)	<0.001
Missing	31 (4.1)	26 (4.9)
ASA
1–2	329 (43.9)	261 (49.2)
3–4	420 (56.1)	270 (50.8)	0.065
Size of tumor, cm, median (IQR)	7.0 (5.0–9.5)	3.0 (2.2–3.8)	<0.001
Missing	10 (1.3)	0 (0.0)
R.E.N.A.L. Nephromery Score
4–6		241 (45.4)
7–9		245 (46.1)
10–11		25 (4.7)
Missing		20 (3.8)
Surgical approach
Open	348 (46.5)	241 (45.4)
Laparoscopy	371 (49.5)	126 (23.7)
Hand-assisted	29 (3.9)	39 (7.3)
Robot-assisted	1 (0.1)	125 (23.5)	0.704
NSS indication
Elective		512 (96.4)
Imperative		19 (3.6)
Intravenous tumor thrombus, Mayo classification
No venous invasion	651 (86.9)
Level 0	54 (7.2)
Level 1	14 (1.9)
Level 2	25 (3.3)
Level 3	3 (0.4)
Level 4	2 (0.3)
Lymhadenectomy
Yes	71 (9.5)	5 (0.9)
No	678 (90.5)	526 (99.1)	0.001
Pathological classification
Malignant	689 (92.0)	433 (81.5)
Benign	59 (7.9)	98 (18.5)	<0.001
Missing	1 (0.1)	0 (0.0)
Metastatic
M0 benign	59 (7.9)	98 (18.5)
M0	551 (73.6)	426 (80.2)
M1	135 (18.0)	7 (1.3)	<0.001
Missing	4 (0.5)	0 (0.0)
Lymphnodes
Benign Kidney tumor	59 (7.9)	98 (18.5)
pNX/pN0	644 (86,0)	431 (81.2)
pN1	42 (5.6)	1 (0.2)	<0.001
Missing	4 (0.5)	1 (0.2)
EBL median (IQR, ml	200 (50–630)	200 (100–465)	0.896
Missing	4 (0.5)	3 (0.6)
Blood transfusion, number of PRBCs during operation, n (%)
0	622 (83.0)	500 (94.2)
1–2	77 (10.3)	25 (4.7)
3–4	22 (2.9)	3 (0.6)
≥5	27 (3.6)	3 (0.6)

*Statistical tests were performed between categories CCI 0–1/≥2, ECOG 0–1/2–4, ASA 1–2/3–4, open/minimally-invasive, pN1/pN0-X. Differences between medians were tested with Kruskal–Wallis and between means with t-test. Categorized values were test with Chi square test.

CCI: Charlson comorbidity index; IQR: inter quartile range; ECOG: Eastern Cooperative Oncology Group performance status; NSS: nephron sparing indication; EBL: estimated blood loss; PRBS: packed red blood cells.

Table 2. Intraoperative adverse events and treatment graded for EAUiaiC.

Radical nephrectomy (N = 749)		Partial nephrectomy (N = 531)
Event/Treatment (grade)	N	Event/Treatment (grade)	N
Inadvertant ligation of renal artery in the opposite side/removal of the clamp (5A)	1	Inadvertant ligation of a renal arterial branch/Ischemic injury comparable to partial nephrectomy (4A)	1
Diaphragm injury/suturation (2)	5	Kidney injury/hemostatic agents (1)	2
Diaphragm injury/suturation, conversion lap open (4B)	1	Urine leakage from resection fossa/conversion partial radical (4A)	1
Pleura injury/suturation (2)	6	Tumor rupture and spillage/resection of fatty tissue around (2)	1
Spleen injury/hemostatic agents (1)	10	Oncological assessment changed during resection/conversion partial radical (4A)	3
Spleen injury/splenectomy (4A)	2	Tumor incision during resection/conversion partial radical (4A)	2
Renal pedicle bleeding/hemostasis (2)	1	Resection of false part of kidney/new operation (5A)	1
Renal pedicle bleeding/hemostasis, blood (3)	6	Renal fossa bleeding/suturing blood (3)	2
Renal pedicle bleeding/hemostasis, hand-port (3)	2	Renal fossa bleeding/suturing, conversion lap open (4B)	2
Renal pedicle bleeding/hemostasis, conversion lap open (4B)	3	Pleura injury/suturation (2)	3
Renal vein with tumor thrombus resected incompletely/re-resection, blood (3)	1	Renal pedicle bleeding/hemostasis (2)	1
IVC injury/suturing, no blood (2)	2	Renal pedicle bleeding/hemostasis, hand-port (3)	1
IVC injury/suturing, blood (3)	9	Renal pedicle bleeding/conversion partial radical (4A)	4
IVC injury/suturing, conversion lap open (4B)	3	Renal pedicle bleeding/hemostasis, conversion lap open (4B)	1
Renal artery bleeding/ligation, blood (3)	1	IVC injury/suturing, no blood (2)	2
Renal artery bleeding/ligation, conversion lap open (4B)	1	IVC injury/suturing, blood (3)	1
Renal artery bleeding, Hemolock opened/Ligation, conversion lap open (4B)	1	Vena llienalis injury/suturing, blood (3)	1
Lumbal artery bleeding/suturing, blood (2)	1	Bleeding unspecified origin/hemostasis, blood (2)	2
Collateral veins bleeding/hemostasis, blood (3)	2	Liver injury/hemostatic agents (1)	1
Bleeding unspecified origin/hemostasis, blood (2)	16	Colon injury/suturing (2)	1
Bleeding unspecified origin/hemostasis, blood (3)	14	Small bowel injury	1
Bleeding unspecified origin/hemostasis, conversion lap open (4B)	4	Ureter injury/suturing (2)	3
Liver injury/hemostatic agents (1)	5	Hypotonia anafylaxia/conversion partial radical (4A)	1
Liver injury/suturing, blood transfusions (3)	2	Embolia pulmonis hypotonia/conversion partial radical (4A)	1
Colon injury/suturing (2)	2	Gallbladder injury retractor/removal of gallbladder (4A)	1
Colon injury/suturation, conversion lap open (4B)	1
Small bowel injury/suturing (2)	2
Small bowel injury/suturing, conversion lap open (4B)	1
Duodenal injury/suturing (2)	2
Adrenal injury bleeding/suturing, blood (2)	1
Adrenal injury bleeding/adrenalectomy (4A)	1
Breakdown of the removal bag/enlargement of the wound (2)	1

Grade 0: Event requiring no intervention or change in operative approach, no deviation from planned intraoperative steps, no consequence for the patient = no complication.

Grade 1: Event requiring additional/alternative procedure in planned intraoperative steps, not life-threatening or involving part or full organ removal. The event was addressed in a controlled manner with no long-term side effects.

Grade 2: Event requiring major additional/alternative procedure in operative approach but NOT immediately life-threatening. The event was addressed in a controlled manner, however, may have short- or long-term side effects.

Grade 3: Event requiring major additional/alternative procedure in addition to planned intraoperative steps and incident becoming immediately life- threatening but NOT requiring part or full organ removal; may have short- or long-term side effects.

Grade 4: Event requiring major additional/alternative procedure in addition to planned intraoperative steps becoming immediately life-threatening and with short- or long-term consequences to patient.

Grade 4A: Requiring part or full organ removal.

Grade 4B: Unable to complete planned procedure as planned due to a technical issue or surgical event and/or required unplanned stoma (change in body image, e.g. stoma, major skin flap).

Grade 5A: Wrong site or side for ablative surgery or removal of an organ or wrong patient or no consent.

Grade 5B: Intraoperative death.

EAUiciC: EAU intraoperative incidents grading classification; IVC: inferior vena cava.

Table 3. Patients undergoing kidney tumor surgery graded for the presence of intraoperative adverse events according to EAUiaiC (the highest grade).

	Radical nephrectomy (n = 749)	Partial nephrectomy (n = 531)
Grade	N (%)	N (%)	p*
No IAE (Grade 0)	646 (86.2)	497 (93.6)
Grade 1	11 (1.5)	1 (0.2)
Grade 2	35 (4.7)	12 (2.3)
Grade 3	38 (5.1)	5 (0.9)
Grade 4A	3 (0.4)	12 (2.3)
Grade 4B	15 (2.0)	3 (0.6)
Grade 5A	1 (0.1)	1 (0.2)
Grade 5B	0 (0.0)	0 (0.0)
IAEs Grades 1–2	46 (6.1)	13 (2.4)	0.002
IAEs Grades 3–5	57 (7.6)	21 (4.0)	0.007
Any IAEs	103 (13.8)	34 (6.4)	<0.001

*Chi square test.

EAUiaiC: EAU intraoperative adverse incident classification; IAE: intraoperative adverse event.

Table 4. Multivariable logistic regsession analyses on preoperative variables to predict any intraoperative adverse events for EAUiaiC in patients undergoing kidney tumor surgery.

Variable	Categories		OR	95%CI	p
A) Partial nephrectomy
Size of tumor	cm		1.30	1.07–1.59	0.009
Age	Year		1.05	1.01–1.09	0.011
CCI	0–1	Ref.	1.0
	> =2		2.13	1.03–4.42	0.041
B) Radical nephrectomy
ASA	1–2	Ref.	1.0
	3–4		1.78	1.10–2.89	0.021
Size of tumor	cm		1.14	1.07–1.22	<0.001
Surgical approach	Open	Ref.	1.0
	Minimally invasive		0.38	0.21–0.67	0.001
Intravenous tumor	No or renal vein	Ref.	1.0
	IVC levels 1–4		4.17	2.10–8.30	<0.001
Cytoreductive indication	No	Ref.	1.0
	Yes		1.78	1.07–2.95	0.026

The variables included in the analyses were surgical approach, size of tumor, lymphadenectomy, sex, age, BMI, Charlson comorbidity index, ASA, Eastern Co-operative Oncology Group performance status, R.E.N.A.L. score (only for PN), nephron sparing indication (elective/imperative, only for PN), intravenous tumor (only RN), cytoreductive indication.

IVC: inferior vena cava; ASA: American Society Anaesthesiology classification; CCI: Charlson Comorbidity Index; EAUiaiC: EAU intraoperative adverse incident classification.

Table 5. Postoperative outcome as 90-day Clavien–Dindo complications (CDC) grade 2–5 and length of stay (LOS) correlated to the presence of any intraoperative adverse events according to the modified EAUiaiC.

Radical nephrectomy (n = 749)
	EAUiaiC
Variable	Grade 0	Grade 1–2	Grade 3–5	p*
CDC 2–5 N (%)	125/646 (19.3)	14/46 (30.4)	23/57 (40.4)	<0.001
LOS, days, mean (SD)	5.0 (2.5)	6.6 (2.9)	8.0 (5.5)	<0.001
Partial nephrectomy (N = 531)
	EAUiaiC
Variable	Grade 0	Grade 1–2	Grade 3–5
CDC 2–5 N (%)	142/497 (28.6)	7/13 (53.9)	9/21 (42.9)	0.023
LOS, days, mean (SD)	5.1 (2.8)	8.7 (8.3)	7.3 (4.7)	0.014

*Chi square and t-tests were done between Grade 0 and Grade 1–5.

CDC: Clavien–Dindo classification; LOS: length of stay; EAUiaiC: European Urology Association classification of intraoperative adverse incident classification.