Table 1 Baseline characteristics compared on the basis of actual body mass index category in three groups of patients with septic shock
Baseline characteristics | Actual body mass indexa category, kg/m2 | P value | ||
|---|---|---|---|---|
BMI <25 (n = 276) | BMI 25 to <30 (n = 209) | BMI ≥30 (n = 245) | ||
Demographics | ||||
Age, years | 63 (48-74) | 64 (50-73) | 63 (53-72) | 0.62 |
Gender: Male, number (percentage) | 171 (62) | 142 (67.9) | 136 (55.5) | 0.03b |
Race: Caucasian, number (percentage) | 231 (83.7) | 177 (84.7) | 209 (85.3) | 0.88 |
Body mass indexa, kg/m2 | 23 (20-24) | 28 (26-29) | 34 (32-39) | <0.0001b |
Severity of illness | ||||
APACHE II score | 27 (21-32) | 26 (22-31) | 27 (23-32) | 0.51 |
Surgical condition, number (percentage) | 52 (18.8) | 45 (21.5) | 58 (23.7) | 0.4 |
In-hospital steroid treatment, number (percentage) | 211 (76.7) | 167 (79.9) | 172 (70.8) | 0.07 |
Pre-existing conditions, number (percentage) | ||||
Chronic obstructive pulmonary disease | 44 (15.9) | 31 (14.8) | 41 (16.7) | 0.86 |
Congestive heart failure | 19 (6.9) | 14 (6.7) | 22 (9.0) | 0.57 |
Chronic liver disease | 27 (9.8) | 30 (14.4) | 26 (10.6) | 0.26 |
Chronic renal failure | 29 (10.5) | 24 (11.5) | 27 (11) | 0.94 |
Diabetes | 41 (14.9) | 43 (20.6) | 73 (29.8) | <0.0001b |
Ischemic heart disease | 40 (15.4) | 38 (20) | 50 (21.8) | 0.18 |
Chronic steroid use | 67 (24.3) | 42 (20.1) | 51 (20.8) | 0.48 |
Hemodynamic variables at day 1 | ||||
Central venous pressure, mm Hg | 14 (10-17) | 14 (11-18) | 15 (12-18) | 0.002b |
Mean arterial pressure, mm Hg | 55 (50-60) | 56 (51-61) | 55 (49-61) | 0.09 |
Heart rate, beats per minute | 130 (115-144) | 125 (112-140) | 125 (106-140) | 0.05 |
Mechanical ventilation variables at day 1 | ||||
Tidal volume, mL | 530 (450-630) | 570 (480-650) | 571 (490-650) | 0.03b |
Tidal volume, mL/kg of PBWc | 8.3 (7.0-9.7) | 8.8 (7.4-10.3) | 9.3 (7.9-10.8) | <0.0001b |
Laboratory variables at day 1 | ||||
White blood cells, x103/mm3 | 14.5 (6.7-21.8) | 13.1 (8.0-19.2) | 12.8 (7.4-20.2) | 0.72 |
Platelets, x103/mm3 | 145 (55-256) | 144 (72-232) | 165 (90.5-254.5) | 0.13 |
Creatinine, µmol/L | 130 (80-218) | 150 (104-266) | 191 (120-297) | <0.0001b |
GFR, mL/minute | 44 (26-76) | 45 (25-72) | 47 (29-77) | 0.27 |
Lactate, mmol/L | 2.0 (1.2-4.2) | 2.1 (0.9-3.8) | 1.7 (1.1-3.5) | 0.27 |
PaO2/FiO2 | 180 (120-255) | 182 (123-255) | 190 (135-259) | 0.41 |