Table 3.
Preoperative demographics and intraoperative data of patients 2 months before and after ventilator exchange after risk matching
| Preoperative variable | Before vent exchange (n = 864) | After vent exchange (n = 864) | p |
|---|---|---|---|
|
Age (mean ± SD, yr) |
49 ± 16 |
48 ± 16 |
0.656 |
|
Male (n,%) |
358 (41%) |
362 (42%) |
0.884 |
|
Patient ASA 3,4 or 5 (n,%) |
198 (23%) |
188 (22%) |
0.603 |
|
Emergent Case (n,%) |
24 (3%) |
16 (2%) |
0.263 |
|
Predicted Body Weight (mean ± SD, kg) |
64 ± 10.5 |
63 ± 10.5 |
0.294 |
|
Weight (mean ± SD, kg) |
84 ± 23.5 |
84 ± 22.8 |
0.658 |
|
BMI (mean ± SD, kg/m
2
) |
28.9 ± 7.4 |
29.0 ± 7.3 |
0.854 |
|
Smoker |
|
|
|
|
Former (n,%) |
141 (16%) |
134 (16%) |
0.693 |
|
Current (n,%) |
138 (16%) |
132 (15%) |
0.74 |
|
Lung Disease (n,%) |
3 (0.3%) |
5 (0.6%) |
0.726 |
|
Asthma (n,%) |
71 (8%) |
72 (8%) |
1 |
|
COPD (n,%) |
20 (2%) |
19 (2%) |
1 |
|
Diabetes (n,%) |
86 (10%) |
73 (8%) |
0.381 |
|
Hypertension (n,%) |
250 (29%) |
230 (27%) |
0.308 |
|
Coronary Artery Disease (n,%) |
23 (3%) |
18 (2%) |
.527 |
|
Congestive Heart Failure (n,%) |
12 (1%) |
12 (1%) |
1 |
|
Chronic Kidney Disease (n,%) |
21 (2%) |
20 (2%) |
1 |
|
Hepatic Disease (n,%) |
11 (1%) |
11 (1%) |
1 |
|
Alcohol Abuse (n,%) |
27 (3%) |
21 (2%) |
0.464 |
|
Current Steroid Therapy (n,%) |
24 (3%) |
25 (3%) |
1 |
|
Intraoperative variable |
Before vent exchange (n = 864) |
After vent exchange (n = 864) |
p |
|
Ventilatory Parameters (case medians) |
|
|
|
|
PIP (mean ± SD, cmH
2
O) |
25.3 ± 5.7 |
20.3 ± 6.2 |
< 0.001 |
|
PEEP (mean ± SD, cmH
2
O) |
2.0 ± 1.3 |
1.5 ± 2.5 |
< 0.001 |
| ΔP (mean ± SD, cmH
2
O) |
23.3 ± 5.4 |
18.8 ± 5.6 |
< 0.001 |
|
RR (mean ± SD, breath per minute) |
11.0 ± 2.3 |
10.5 ± 2.2 |
< 0.001 |
|
Vt (mean ± SD, ml) |
587 ± 146 |
559 ± 125 |
< 0.001 |
|
Vt cc/kg PBW (mean ± SD, ml) |
9.33 ± 2.22 |
8.98 ± 1.94 |
< 0.001 |
|
FiO
2
(mean ± SD,%) |
55.5 ± 16 |
51.2 ± 18 |
< 0.001 |
|
cc/kg PBW ≤ 6 (n,%) |
62 (7%) |
63 (7%) |
1 |
|
cc/kg PBW ≤ 8 (n,%) |
188 (22%) |
219 (34%) |
0.089 |
|
Epochs of 10 minutes: |
|
|
|
|
PIP > 30 cmH2O |
2.9 ± 6.4 |
1.4 ± 4.5 |
< 0.001 |
|
Vt > 12 cc/kg PBW |
1.7 ± 4.3 |
0.9 ± 3.6 |
< 0.001 |
|
Colloid use (n,%) |
51 (5.9%) |
47 (5.4%) |
0.755 |
|
Crystalloid volume (median, 25
th
,75
th
, ml) |
1950 (1100, 2700) |
1900 (1000,2500) |
0.111 |
|
Case Length (mean ± SD, minutes) |
198 ± 103 |
195 ± 104 |
0.531 |
|
Transfusion (n,%) |
17 (2%) |
15 (2%) |
0.858 |
|
PRBC (n,%) |
16 (2%) |
15 (5%) |
1 |
|
FFP (n,%) |
2 (0.2%) |
4 (0.5%) |
0.683 |
| Platelets (n,%) | 2 (0.2%) | 1 (0.1%) | 1 |
ASA = American Society of Anesthesiology Classification, BMI = body mass index, COPD = chronic obstructive pulmonary disease, PIP = peak inspiratory pressure, PEEP = positive end expiratory pressure, RR = respiratory rate, Vt = tidal volume, PBW = predicted body weight, FiO2 = fraction inspired oxygen, PBW = predicted body weight, PRBC = packed red blood cells, FFP = fresh frozen plasma.