Comparison of the acute-phase response after laparoscopic versus open aortobifemoral bypass surgery: a substudy of a randomized controlled trial

Figures & data

Figure 1 Flowchart of patient population with aortoiliac occlusive disease (AIOD) treated with totally laparoscopic aortobifemoral bypass (LABF) or open aortobifemoral bypass (OABF).

Table 1 Baseline characteristics of patients treated with either totally laparoscopic or open aortobifemoral bypass for severe aortoiliac occlusive disease

Baseline characteristics	Laparoscopy (N=14)	Open surgery (N=16)	P-value
Age (years), mean (SD)	59 (7.2)	64 (6.8)	0.1043d
Female sex, N (%)	7 (50)	9 (56)	0.5095e
Body mass index (kg/m^2), mean (SD)	26.3 (4.2)	24.0 (5.1)	0.2056d
Current smoker, N (%)	7 (50)	10 (63)	0.1038e
Hypertension, N (%)	10 (71)	11 (69)	1.0000e
Renal failure, N (%)	0 (0)	1 (6)	1.0000e
COPD, N (%)	4 (29)	3 (19)	0.6746e
Hyperlipidemia, N (%)	5 (36)	2 (13)	0.2040e
Diabetes mellitus, N (%)	1 (7.1)	0 (0)	0.4667e
Coronary heart disease, N (%)	2 (14)	5 (31)	0.3992e
Statin, N (%)	12 (86)	15 (94)	0.5862e
Acetylsalicylic acid, N (%)	13 (93)	15 (94)	1.0000e
ASA classificationa
ASA class 2, N (%)	0 (0)	1 (6)	1.0000e
ASA class 3, N (%)	14 (100)	15 (94)
Fontaine classificationb
Fontaine class 3, N (%)	11 (79)	12 (75)	1.0000e
Fontaine class 4, N (%)	3 (21)	4 (25)
Critical limb ischemia, N (%)	3 (21)	4 (25)	1.0000e
Ankle brachial indexc (preoperative), median (IQR)	0.57 (0.40–0.60)	0.37 (0.27–0.50)	0.0083d

Notes:

a American Society of Anesthesiologists (ASA) classification;

b Fontaine classification (classification of symptoms in peripheral atherosclerotic disease);

c ABI preoperative) in leg with lowest ABI;

d Mann—Whitney U-test; and

e Fisher’s exact test.

Abbreviations: ABI, ankle brachial index; IQR, interquartile range; SD, standard deviation.

Figure 2 Comparing mean serum level of interleukin-6 (pg/mL) at different time points during and after totally laparoscopic aortobifemoral bypass (LABF) versus open aortobifemoral bypass (OABF).

Notes: Error bars represent the 95% confidence interval (CI). Timepoints: 1, before surgery; 2, after completion of distal anastomosis and flow to one of the lower limbs was reestablished; 3, 6 hours after beginning of surgery; 4, 12 hours after beginning of surgery; 5, 24 hours after beginning of surgery; 6, at discharge from hospital.

Figure 3 Comparing mean serum level of Interleukin-8 (pg/mL) at different time points during and after totally laparoscopic aortobifemoral bypass (LABF) versus open aortobifemoral bypass (OABF).

Notes: Error bars represent the 95% confidence interval (CI). Timepoints: 1, before surgery; 2, after completion of distal anastomosis and flow to one of the lower limbs was reestablished; 3, 6 hours after beginning of surgery; 4, 12 hours after beginning of surgery; 5, 24 hours after beginning of surgery; 6, at discharge from hospital.

Figure 4 Comparing mean serum level of C-reactive protein (CRP) (mg/L) at different time points during and after totally laparoscopic aortobifemoral bypass (LABF) versus open aortobifemoral bypass (OABF).

Notes: Error bars represent the 95% confidence interval (CI). Timepoints: 1, before surgery; 2, after completion of distal anastomosis and flow to one of the lower limbs was reestablished; 3, 6 hours after beginning of surgery; 4, 12 hours after beginning of surgery; 5, 24 hours after beginning of surgery; 6, at discharge from hospital.

Table 2 Comparison of area under curve (AUC) in laparoscopic aortobifemoral bypass (LABF) versus open aortobifemoral bypass (OABF) for the serum levels of interleukin-6 (IL-6), IL-8, and C-reactive protein (CRP)

Inflammation marker	Treatment	N	Median	Mean	Logged mean	SD	Difference in logged mean	tdf=28	P-value
IL-6	LABF	14	235.9	273.8	50.8	14.2	21.0	3.300	0.0026
	OABF	16	965.4	875.9	71.8	19.8
IL-8	LABF	14	374.2	463.6	65.7	12.6	10.6	1.960	0.0600
	OABF	16	565.5	790.1	76.3	16.4
CRP	LABF	14	362.5	464.9	55.8	18.5	2.4	0.390	0.6993
	OABF	16	554.4	594.3	58.1	14.8

Abbreviation: SD, standard deviation.

Table 3 The effect of laparoscopic aortobifemoral bypass (LABF) versus open aortobifemoral bypass (OABF) on serum levels of interleukin-6 (IL-6), IL-8, and C-reactive protein (CRP), controlling for the confounding effect of coronary heart disease, using the general estimated equations (GEE) model

Inflammation marker	Coefficient	SE	Z	P-value	Confounding effect
IL-6
Crude effect	−0.7024	0.2484	−2.83	0.005
Adjusted for CHD	−0.6407	0.2488	−2.58	0.010	8.8%
IL-8
Crude effect	−0.2695	0.1973	−1.37	0.172
Adjusted for CHD	−0.2360	0.2005	−1.18	0.237	5.3%
CRP
Crude effect	−0.0963	0.3739	−0.26	0.797
Adjusted for CHD	−0.0562	0.3808	−0.15	0.883	41.6%

Note: The confounding effect is quantified using the formula: (Coefficient_adjusted − Coefficient_crude)/Coefficient_crude × 100.

Abbreviations: SE, standard error; CHD, coronary heart disease.

Table 4 Operation-related parameters for patients treated with either totally laparoscopic or open aortobifemoral bypass for severe aortoiliac occlusive disease

Parameters	Laparoscopy (N=14)	Open surgery (N=16)	P-value
Operation time (minutes), median (IQR)	216 (195–235)	202 (169–230)	0.2600a
Blood loss during surgery (mL), median (IQR)	275 (150–600)	1,000 (575–1,150)	0.0300a
Suprarenal clamping, N (%)	1 (7.1)	1 (6.3)	0.9200b
Aortic clamping time (minutes),c median (IQR)	43 (41–52)	30 (20–38)	0.0002a

Notes: Statistics:

a Mann–Whitney U-test;

b Fisher’s exact t-test;

c aortic clamping time defined as: time from cross-clamping of the aorta above the proximal anastomosis until the clamp is moved to the proximal end of the graft.

Abbreviation: IQR, interquartile range.

Table 5 Clinical outcome after laparoscopic aortobifemoral bypass (LABF) versus open aortobifemoral bypass (OABF)

Clinical outcome	Laparoscopy	Open surgery	P-value
Length of stay in hospital (days), median (IQR)	5.0 (4.0–6.0)	9.0 (6.5–11.0)	0.001a
Thirty-day mortality, N	0	0
Thirty-day systemic morbidity,c N (%)	1 (7)	4 (25)	0.210b

Notes: Statistics:

a Mann–Whitney U-test;

b Fisher’s exact test; and

c systemic morbidity is defined as systemic complications including systemic infection, ileus, sepsis, acute respiratory distress syndrome, multiple organ failure, renal failure, myocardial infarction, and/or cerebral infarction/hemorrhage. Not including local morbidity defined as local wound infection, lymphatic discharge from wound, simple urinary tract infections, pneumonia, or graft occlusion.

Abbreviation: IQR, interquartile range.