Figures
- Figure 1–
Flow chart of patients operated for lung cancer and stratified according to pre-operative peak oxygen uptake (V′O2) values. Post-operative morbidity data are expressed as n (%). FEV1: forced expiratory volume in 1 s; CPET: cardiopulmonary exercise testing.
- Figure 2–
Stratification of post-operative outcome according to peak oxygen uptake (V′O2) values expressed as mL·kg−1·min−1. Incidence of cardiac, pulmonary and total cardiopulmonary complications during the hospital stay following surgery.
Tables
- Table 1– Baseline characteristics stratified by peak oxygen uptake (V′O2)
Characteristics V′O2 mL·min−1·kg−1 p-value ≤10 11– <17 17– <20 ≥20 Patients n 29 90 52 39 Age yrs 68±10 65±9 64±9 53±11 0.022 BMI kg·m−2 28.4±5.1 25.5±4.6 24.8±5.8 23.9±4.7 0.009 Males 18 (62) 61 (68) 36 (69) 30 (76) 0.023 ASA risk classes 3 and 4 14 (48) 39 (43) 21 (40) 6 (15) 0.011 Smoking status Unit pack-yrs 46±24 42±21 43±20 44±22 0.652 Current smoker 18 (62) 59 (66) 32 (62) 24 (62) 0.712 Ex-smoker# 4 (14) 10 (11) 6 (12) 4 (10) 0.694 Alcohol status 4 (14) 17 (19) 9 (17) 1 (13) 0.751 Coronary artery disease 3 (10) 7 (8) 4 (8) 2 (5) 0.854 Hypertension 13 (45) 35 (39) 16 (31) 7 (18) 0.004 Hypercholesterolaemia 5 (17) 21 (23) 12 (23) 4 (10) 0.324 Diabetes mellitus 1 (3.4) 9 (10) 4 (8) 3 (8) 0.852 Haematocrit 45 (20) 42 (6) 42 (4) 45 (20) 0.325 Creatinine clearance mL·min−1 86±23 79±29 79±30 82±27 0.309 FEV1 % pred 65±19 79±22 82±25 88±21 <0.001 ppo FEV1 % pred 50±19 55±20 58±17 64±19 <0.001 DL,CO % pred 64±16 74±17 NA NA ppo DL,CO % pred 51±10 59±18 NA NA V′O2,max mL−1·kg−1 9.0±1.6 13.7±1.2 17.6±1.1 24.4±4.6 <0.001 V′O2,max mL−1·kg−1 PBW 11.6±2.9 15.8±3.1 20±3.6 25.4±5.4 <0.001 V′O2,max % pred 39±11 52±13 65±14 76±16 <0.001 Load W 83±32 93±23 113±27 137±36 <0.001 V′E,max L·min−1 37±10 48±11 57±16 68±15 <0.001 V′E,max % pred 75±15 78±17 89±17 99±17 <0.001 Pa,O2 end exercise mmHg 63±18 66±22 73±12 74±16 <0.001 Neoadjuvant chemotherapy 4 (14) 12 (13) 6 (12) 6 (15) 0.534 Pathological stages Ia and Ib 16 (55) 37 (41) 20 (38) 12 (31) 0.021 Pneumonectomy or bilobectomy 5 (17) 16 (18) 13 (25) 5 (13) 0.458 Data are presented as mean±sd or n (%), unless otherwise stated. BMI: body mass index; ASA: American Society Association; FEV1: forced expiratory volume in 1 s; ppo: predicted post-operative; DL,CO: diffusing capacity of the lung for carbon monoxide; V′O2,max: maximal oxygen uptake; PBW: predicted body weight; V′E,max: minute ventilation during maximal exercise; Pa,O2: arterial oxygen pressure; % pred: % predicted; NA: not available. #: >6 months smoking cessation.
- Table 2– Clinical and surgical characteristics of patients with and without complications
Total morbidity Cardiovascular complications Respiratory complications Yes No Yes No Yes No Pre-operative period Patients n 46 164 24 186 28 182 Age yrs 66±9 62±11 69±9 62±8# 65±9 63±11 BMI kg·m−2 26.4±6.0 25.1±4.8 25.7±4.5 25.4±5.2 27.0±6.8# 25.2±4.8 Males 34 (74) 110(67) 19 (79) 125 (67) 21 (72) 144 (80) ASA classes 3 and 4 22 (48) 58 (35) 13 (54) 67 (36) 15 (53) 80 (44) Smoking status Unit pack-yrs 44±21 42±23 45±23 41±24 46±23 43±21 Current smoker 32 (69) 101(62) 17 (71) 116 (62) 20 (71) 113 (62) Ex-Smoker# 6 (13) 18 (11) 3 (12) 21 (11) 3 (11) 21 (12) Alcohol status 8 (17) 23 (14) 4 (17) 27 (14) 6 (21) 25 (14) Coronary artery disease 6 (13.0) 11 (6.7) 3 (12.5) 14 (7.5) 3 (10.7) 17 (9.4) Hypertension 21 (46) 51 (31) 13 (54) 59 (32) 13 (46) 72 (40) Hyperlipidaemia 11 (24) 32 (20) 8 (33) 35 (19) 4 (14) 43 (24) Diabetes mellitus 2 (4.3) 15 (9.1) 1 (4.2) 16 (8.6) 2 (7.1) 17 (9.4) FEV1 % pred 77±23 80±23 78±22 80±23 74±22 80±23 ppo FEV1 % pred 56±18 61±21 55±16 61±19 54±15# 62±17 Hematocrit 40.3 (6.7) 41.9 (4.4) 38.5 (6.4)# 42.1 (4.6) 41.4 (7.5) 41.6 (4.6) Creatinine clearance mL·min−1 80±33 84±25 73±18# 85±27 78±37 82±25 V′O2,max mL·min−1.kg−1 13.0±4.4# 16.9±5.2 13.0±4.3 16.5±5.3 15.2±6.3# 18.5±5.6 V′O2,max mL·min−1·kg−1 PBW 15.0±5.5# 18.9±5.6 14.3±4.0# 18.6±5.8 12.7±4.6# 16.6±5.2 V′O2,max % pred 50±17# 60±17 50±14# 59±18 49±20# 59±17 Load W 90±30# 109±34 89±35# 107±33 87±26# 108±34 V’E,max L.min−1 47±17# 54±16 48±18 53±16 46±15# 53±16 V′E,max %pred 60±21 65±17 65±27 64±16 56±12# 65±18 Pa,O2 end exercice mmHg 64±21 70±18 58±24# 70±17 67±20 69±18 Intra-operative period Surgical time min 111±42# 97±29 123±42# 97±30 109±41 99±31 Anaesthesia time min 152±64# 123±35 160±52# 125±42 154±74# 125±37 Pneumonectomy or bilobectomy 12 (26) 27 (16) 10 (42)* 29 (15) 6 (21) 33 (18) VT during TLV mL·kg−1 PBW 8.1±2.3 7.4±2.1 7.9±2.3 7.6±2.2 8.8±1.9# 6.9±2.0 VT during OLV mL·kg−1 PBW 6.9±2.2 6.5±2.1 7.0±2.9 6.4±2.7 7.0±1.9# 5.6±1.8 Phenylephrine mg 580±442# 384±348 597±524# 405±348 635±431# 397±358 Fluid mL·kg−1·h−1 9.6±5.9 8.8±3.5 9.4±7.1 8.9±3.6 9.1±4.1 8.9±4.2 Data are presented as mean±sd or n (%), unless otherwise stated. BMI: body mass index; ASA: American Society Association; FEV1: forced expiratory volume in 1 s; ppo: predicted post-operative; V′O2,max: maximal oxygen uptake; PBW: predicted body weight; V′E,max: minute ventilation during maximal exercise; Pa,O2: arterial oxygen pressure; % pred: % predicted; VT: tidal volume; TLV: two-lung ventilation; OLV: one-lung ventilation. #: quit smoking >6 months ago.
- Table 3– Characteristics of the four patients who died within the perioperative period
Patient Age yrs Sex BMI kg·m−2 Operation Comorbidities Peak V′O2 mL·kg−1·min−1# Peak V′O2 % pred ppo FEV1 % pred Cause of death 1 82 M 28.7 RUL Alcohol¶ 8.2 41 63 Stroke (day 6) 2 61 M 26.3 LP CAD Hyperlipidaemia 8.4 31 45 Myocardial infarction, stent thrombosis, heart failure (day 10) 3 57 F 27.9 RP Hypertension Alcohol¶ 9.1 32 39 ALI, MOF (day 9) 4 68 M 27.2 LUL Hypertension Hyperlipidaemia Alcohol¶ 13.6 49 62 Pulmonary thrombo-embolism (day 4) BMI: body mass index; M: male; F: female; V′O2 : oxygen uptake; ppo: predicted post-operative; FEV1: forced expiratory volume in 1 s ; RUL: right upper lobectomy; LP: left pneumonectomy; CAD: coronary artery disease; RP: right pneumonectomy; ALI: acute lung injury; MOF: multiple organ failure; LUL: left upper lobectomy. #: expressed in mL·min−1·kg−1 absolute body weight; ¶: alcohol: >21 drinks per week for men or >14 drinks per week for women.
- Table 4– Results of logistic regression analysis for different dependent variables
Independent predictor Coefficient sem OR (95% CI) p-value Bootstrap frequency % Total morbidity Constant 0.2980 79 Duration of anaesthesia 0.0145 0.0041 1.015 (1.006–1.023) 0.0005 Peak V′O2 in mL·min−1·kg−1 -0.2353 0.0546 0.79 (0.71–0.88) <0.0001 81 Cardiovascular complications Constant -6.5727 Age 0.0804 0.0318 1.084 (1.018–1.153) 0.0115 62 Duration of anaesthesia 0.0143 0.0045 1.014 (1.005–1.024) 0.0016 72 Pneumonectomy or bilobectomy 1.7518 0.5674 5.76 (1.90–17.53) 0.0020 71 Peak V′O2 mL·min−1·kg−1 -0.2286 0.0768 0.80 (0.68–0.92) 0.0029 69 Pulmonary complications Constant -21.0904 Duration of anaesthesia 0.0133 0.0042 1.013 (1.005–1.022) 0.032 66 Peak V′O2 mL·min−1·kg−1 -0.1752 0.0590 0.840 (0.749–0.942) 0.021 70 VT mL·kg−1 PBW 2.8249 0.5384 1.65 (1.27–4.49) 0.003 77 V′O2: oxygen uptake; VT: tidal volume; PBW: predicted body weight.
- Table 5– Areas under the receiver operating characteristic curves and cut-off values of various parameters for the prediction of cardiovascular and pulmonary complications
Area under the curve se Lower–upper bound p-value Cut-off Sensitivity % Specificity % Total morbidity V′O2 kg−1 0.717 0.045 0.651–0.777 0.0001 12.8 51 85 V′O2 kg−1 PBW 0.710 0.045 0.643–0.771 0.0001 15.8 64 69 V′O2% pred 0.657 0.045 0.589–0.722 0.0010 58 75 48 ASA score 0.593 0.039 0.523–0.661 0.0156 3 71 48 ppo FEV1 0.565 0.045 0.495–0.633 0.7880 64 65 49 Cardiovascular complications V′O2 kg−1 0.708 0.065 0.640–0.771 0.0011 13.6 63 72 V′O2 kg−1 PBW 0.738 0.054 0.671–0.798 0.0001 16.2 75 61 V′O2% pred 0.633 0.061 0.562–0.700 0.0029 53 64 61 ASA score 0.630 0.046 0.560–0.695 0.0080 3 79 47 ppo FEV1% pred 0.492 0.066 0.422–0.562 0.9030 80 29 79 Pulmonary complications V′O2 kg−1 0.723 0.057 0.654–0.784 0.0001 12.3 56 86 V′O2 kg−1 PBW 0.691 0.065 0.580–0.718 0.0020 12.1 45 94 V′O2% pred 0.616 0.066 0.544–0.684 0.0169 37 30 95 ASA score 0.597 0.044 0.527–0.664 0.0269 3 73 47 ppo FEV1 0.545 0.051 0.480–0.614 0.3716 64 73 50 V′O2: oxygen uptake; PBW: predicted body weight; % pred: % predicted; ASA: American Society Association; FEV1: forced expiratory volume in 1 s; ppo: predicted post-operative.
