Trial Outcomes & Findings for Ventilation Strategy During General Anesthesia for Orthopedic Surgery: A Quality Improvement Project (NCT NCT03657368)
NCT ID: NCT03657368
Last Updated: 2025-08-27
Results Overview
Primary outcome was oxygenation in the postoperative care unit, defined by the peripheral oxygen saturation divided by the fraction of inspired oxygen (SpO2/FiO2 ratio), a validated measure of acute lung injury.
Recruitment status
COMPLETED
Study phase
NA
Target enrollment
2860 participants
Primary outcome timeframe
After surgery until discharged from PACU or up to 90 minutes
Results posted on
2025-08-27
Participant Flow
Participant milestones
| Measure |
Low Tidal Volume and Low PEEP
Ventilation parameters will be set at tidal volume = 6 ml/ kg predicted body weight, and PEEP = 5 cm water (H2O). (n = 727)
Low tidal Volume: Tidal volume = 6 ml/kg predicted body weight
Low PEEP: PEEP = 5 cm H2O
|
Low Tidal Volume and High PEEP
Ventilation parameters will be set at tidal volume = 6 ml/kg predicted body weight, and PEEP = 8 cm H2O. (n = 635)
Low tidal Volume: Tidal volume = 6 ml/kg predicted body weight
High PEEP: PEEP = 8 cm H2O
|
High Tidal Volume and Low PEEP
Ventilation parameters will be set at tidal volume = 10 ml/kg predicted body weight, and PEEP = 5cm H2O. (n = 799)
High tidal Volume: Tidal volume = 10 ml/kg predicted body weight
Low PEEP: PEEP = 5 cm H2O
|
High Tidal Volume and High PEEP
Ventilation parameters will be set at tidal volume = 10 ml/kg predicted body weight, and PEEP = 8cm H2O. (n = 699)
High tidal Volume: Tidal volume = 10 ml/kg predicted body weight
High PEEP: PEEP = 8 cm H2O
|
|---|---|---|---|---|
|
Overall Study
STARTED
|
727
|
635
|
799
|
699
|
|
Overall Study
COMPLETED
|
727
|
635
|
799
|
699
|
|
Overall Study
NOT COMPLETED
|
0
|
0
|
0
|
0
|
Reasons for withdrawal
Withdrawal data not reported
Baseline Characteristics
Ventilation Strategy During General Anesthesia for Orthopedic Surgery: A Quality Improvement Project
Baseline characteristics by cohort
| Measure |
Low Tidal Volume and Low PEEP
n=727 Participants
Ventilation parameters will be set at tidal volume = 6 ml/ kg predicted body weight, and PEEP = 5 cm water (H2O). (n = 727)
Low tidal Volume: Tidal volume = 6 ml/kg predicted body weight
Low PEEP: PEEP = 5 cm H2O
|
Low Tidal Volume and High PEEP
n=635 Participants
Ventilation parameters will be set at tidal volume = 6 ml/kg predicted body weight, and PEEP = 8 cm H2O. (n = 635)
Low tidal Volume: Tidal volume = 6 ml/kg predicted body weight
High PEEP: PEEP = 8 cm H2O
|
High Tidal Volume and Low PEEP
n=799 Participants
Ventilation parameters will be set at tidal volume = 10 ml/kg predicted body weight, and PEEP = 5cm H2O. (n = 799)
High tidal Volume: Tidal volume = 10 ml/kg predicted body weight
Low PEEP: PEEP = 5 cm H2O
|
High Tidal Volume and High PEEP
n=699 Participants
Ventilation parameters will be set at tidal volume = 10 ml/kg predicted body weight, and PEEP = 8cm H2O. (n = 699)
High tidal Volume: Tidal volume = 10 ml/kg predicted body weight
High PEEP: PEEP = 8 cm H2O
|
Total
n=2860 Participants
Total of all reporting groups
|
|---|---|---|---|---|---|
|
Age, Continuous
|
64 years
STANDARD_DEVIATION 15 • n=99 Participants
|
64 years
STANDARD_DEVIATION 14 • n=107 Participants
|
62 years
STANDARD_DEVIATION 15 • n=206 Participants
|
63 years
STANDARD_DEVIATION 14 • n=7 Participants
|
63 years
STANDARD_DEVIATION 14 • n=31 Participants
|
|
Sex: Female, Male
Female
|
360 Participants
n=99 Participants
|
326 Participants
n=107 Participants
|
442 Participants
n=206 Participants
|
376 Participants
n=7 Participants
|
1504 Participants
n=31 Participants
|
|
Sex: Female, Male
Male
|
367 Participants
n=99 Participants
|
309 Participants
n=107 Participants
|
357 Participants
n=206 Participants
|
323 Participants
n=7 Participants
|
1356 Participants
n=31 Participants
|
|
Race/Ethnicity, Customized
race · White
|
603 Participants
n=99 Participants
|
511 Participants
n=107 Participants
|
655 Participants
n=206 Participants
|
575 Participants
n=7 Participants
|
2344 Participants
n=31 Participants
|
|
Race/Ethnicity, Customized
race · Black
|
97 Participants
n=99 Participants
|
108 Participants
n=107 Participants
|
115 Participants
n=206 Participants
|
89 Participants
n=7 Participants
|
409 Participants
n=31 Participants
|
|
Race/Ethnicity, Customized
race · other
|
16 Participants
n=99 Participants
|
12 Participants
n=107 Participants
|
15 Participants
n=206 Participants
|
22 Participants
n=7 Participants
|
65 Participants
n=31 Participants
|
|
Race/Ethnicity, Customized
race · missing
|
11 Participants
n=99 Participants
|
4 Participants
n=107 Participants
|
14 Participants
n=206 Participants
|
13 Participants
n=7 Participants
|
42 Participants
n=31 Participants
|
|
BMI
|
30 kg/m2
STANDARD_DEVIATION 7 • n=99 Participants
|
30 kg/m2
STANDARD_DEVIATION 7 • n=107 Participants
|
31 kg/m2
STANDARD_DEVIATION 8 • n=206 Participants
|
32 kg/m2
STANDARD_DEVIATION 7 • n=7 Participants
|
31 kg/m2
STANDARD_DEVIATION 7 • n=31 Participants
|
|
ASA score
1
|
23 Participants
n=99 Participants
|
9 Participants
n=107 Participants
|
10 Participants
n=206 Participants
|
14 Participants
n=7 Participants
|
56 Participants
n=31 Participants
|
|
ASA score
2
|
122 Participants
n=99 Participants
|
106 Participants
n=107 Participants
|
157 Participants
n=206 Participants
|
120 Participants
n=7 Participants
|
505 Participants
n=31 Participants
|
|
ASA score
3
|
519 Participants
n=99 Participants
|
460 Participants
n=107 Participants
|
572 Participants
n=206 Participants
|
520 Participants
n=7 Participants
|
2071 Participants
n=31 Participants
|
|
ASA score
4 or 5
|
63 Participants
n=99 Participants
|
60 Participants
n=107 Participants
|
60 Participants
n=206 Participants
|
45 Participants
n=7 Participants
|
228 Participants
n=31 Participants
|
|
The total Charlson score
|
1 units on a scale
n=99 Participants
|
1 units on a scale
n=107 Participants
|
1 units on a scale
n=206 Participants
|
1 units on a scale
n=7 Participants
|
1 units on a scale
n=31 Participants
|
|
smoking
|
369 Participants
n=99 Participants
|
346 Participants
n=107 Participants
|
404 Participants
n=206 Participants
|
341 Participants
n=7 Participants
|
1460 Participants
n=31 Participants
|
|
COPD
|
87 Participants
n=99 Participants
|
85 Participants
n=107 Participants
|
103 Participants
n=206 Participants
|
102 Participants
n=7 Participants
|
377 Participants
n=31 Participants
|
|
Obstructive sleep apnea
|
161 Participants
n=99 Participants
|
144 Participants
n=107 Participants
|
202 Participants
n=206 Participants
|
187 Participants
n=7 Participants
|
694 Participants
n=31 Participants
|
|
Asthma
|
119 Participants
n=99 Participants
|
105 Participants
n=107 Participants
|
157 Participants
n=206 Participants
|
102 Participants
n=7 Participants
|
483 Participants
n=31 Participants
|
|
intraoperative use of Rocuronium
|
70 mg
n=99 Participants
|
70 mg
n=107 Participants
|
70 mg
n=206 Participants
|
65 mg
n=7 Participants
|
68 mg
n=31 Participants
|
|
Crystalloids
|
1.7 L
STANDARD_DEVIATION 0.8 • n=99 Participants
|
1.7 L
STANDARD_DEVIATION 0.8 • n=107 Participants
|
1.8 L
STANDARD_DEVIATION 0.8 • n=206 Participants
|
1.7 L
STANDARD_DEVIATION 0.8 • n=7 Participants
|
1.7 L
STANDARD_DEVIATION 0.8 • n=31 Participants
|
|
blood loss
|
150 ml
n=99 Participants
|
150 ml
n=107 Participants
|
200 ml
n=206 Participants
|
150 ml
n=7 Participants
|
150 ml
n=31 Participants
|
|
transfusion
|
48 Participants
n=99 Participants
|
50 Participants
n=107 Participants
|
75 Participants
n=206 Participants
|
50 Participants
n=7 Participants
|
223 Participants
n=31 Participants
|
PRIMARY outcome
Timeframe: After surgery until discharged from PACU or up to 90 minutesPopulation: The mean difference was estimated from a linear mixed regression model with surgeries from same patient as repeated measures, after propensity score weighting.
Primary outcome was oxygenation in the postoperative care unit, defined by the peripheral oxygen saturation divided by the fraction of inspired oxygen (SpO2/FiO2 ratio), a validated measure of acute lung injury.
Outcome measures
| Measure |
TV = 6 ml/kg
n=1362 Participants
tidal volume = 6 ml/kg
|
TV = 10 ml/kg
n=1498 Participants
tidal volume = 10 ml/kg
|
PEEP = 5cmH2O
n=1526 Participants
Positive End-Expiratory Pressure = 5cmH2O
|
PEEP = 8cmH2O
n=1334 Participants
Positive End-Expiratory Pressure = 8cmH2O
|
|---|---|---|---|---|
|
Time-weighted Average SaO2/FiO2 Ratio in the Postanesthesia Care Unit (PACU)
|
355 ratio
Standard Deviation 46
|
350 ratio
Standard Deviation 47
|
353 ratio
Standard Deviation 46
|
352 ratio
Standard Deviation 47
|
SECONDARY outcome
Timeframe: After surgery from 2 to 5 daysPostoperative diagnoses will be collected from electronic medical records of patients. Individual chart reviews (blinded to ventilation management) will confirm that terms of the composite are met will be performed.
Outcome measures
| Measure |
TV = 6 ml/kg
n=1362 Participants
tidal volume = 6 ml/kg
|
TV = 10 ml/kg
n=1498 Participants
tidal volume = 10 ml/kg
|
PEEP = 5cmH2O
n=1526 Participants
Positive End-Expiratory Pressure = 5cmH2O
|
PEEP = 8cmH2O
n=1334 Participants
Positive End-Expiratory Pressure = 8cmH2O
|
|---|---|---|---|---|
|
Composite of Serious Postoperative Pulmonary Complications
|
34 person
|
39 person
|
36 person
|
37 person
|
SECONDARY outcome
Timeframe: After surgery from 2 to 5 daysOxygen administration and SaO2 are normally recorded at 4-hour intervals on surgical wards. The time weighted average (TWA) of overall SaO2/FIO2 ratio will be compared among different ventilation strategies.
Outcome measures
| Measure |
TV = 6 ml/kg
n=1362 Participants
tidal volume = 6 ml/kg
|
TV = 10 ml/kg
n=1498 Participants
tidal volume = 10 ml/kg
|
PEEP = 5cmH2O
n=1526 Participants
Positive End-Expiratory Pressure = 5cmH2O
|
PEEP = 8cmH2O
n=1334 Participants
Positive End-Expiratory Pressure = 8cmH2O
|
|---|---|---|---|---|
|
Oxygenation in Ward, Defined as Time Weighted Average (TWA) of SaO2/FIO2 Ratio
|
428 ratio
Standard Deviation 42
|
430 ratio
Standard Deviation 41
|
429 ratio
Standard Deviation 41
|
429 ratio
Standard Deviation 41
|
SECONDARY outcome
Timeframe: from out of operation room to dischargeThe days of postoperative hospitalization, which from out of operation room to discharge from the hospital, an average of 1 week
Outcome measures
| Measure |
TV = 6 ml/kg
n=1362 Participants
tidal volume = 6 ml/kg
|
TV = 10 ml/kg
n=1498 Participants
tidal volume = 10 ml/kg
|
PEEP = 5cmH2O
n=1526 Participants
Positive End-Expiratory Pressure = 5cmH2O
|
PEEP = 8cmH2O
n=1334 Participants
Positive End-Expiratory Pressure = 8cmH2O
|
|---|---|---|---|---|
|
Length of Postoperative Hospital Stay by Days
|
3 days
Interval 2.0 to 5.0
|
3 days
Interval 2.0 to 5.0
|
3 days
Interval 2.0 to 5.0
|
3 days
Interval 2.0 to 5.0
|
OTHER_PRE_SPECIFIED outcome
Timeframe: from out of operation room to discharge from the hospitalnumber of patients who need of Oxygen in ward after surgery during hospital stay
Outcome measures
| Measure |
TV = 6 ml/kg
n=1362 Participants
tidal volume = 6 ml/kg
|
TV = 10 ml/kg
n=1498 Participants
tidal volume = 10 ml/kg
|
PEEP = 5cmH2O
n=1526 Participants
Positive End-Expiratory Pressure = 5cmH2O
|
PEEP = 8cmH2O
n=1334 Participants
Positive End-Expiratory Pressure = 8cmH2O
|
|---|---|---|---|---|
|
Patients Need of Oxygen in Ward After Surgery
|
855 participants
|
932 participants
|
961 participants
|
826 participants
|
OTHER_PRE_SPECIFIED outcome
Timeframe: from out of operation room to discharge from the hospitalnumber of patients with unplanned ICU admission after surgery in hospital stay
Outcome measures
| Measure |
TV = 6 ml/kg
n=1362 Participants
tidal volume = 6 ml/kg
|
TV = 10 ml/kg
n=1498 Participants
tidal volume = 10 ml/kg
|
PEEP = 5cmH2O
n=1526 Participants
Positive End-Expiratory Pressure = 5cmH2O
|
PEEP = 8cmH2O
n=1334 Participants
Positive End-Expiratory Pressure = 8cmH2O
|
|---|---|---|---|---|
|
Patients With Unplanned ICU Admission
|
44 participants
|
43 participants
|
43 participants
|
44 participants
|
Adverse Events
Low Tidal Volume and Low PEEP
Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths
High Tidal Volume and Low PEEP
Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths
Low Tidal Volume and High PEEP
Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths
High Tidal Volume and High PEEP
Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths
Serious adverse events
Adverse event data not reported
Other adverse events
Adverse event data not reported
Additional Information
Results disclosure agreements
- Principal investigator is a sponsor employee
- Publication restrictions are in place