Atelectasis
Conditions
Keywords
atelectasis, oxygen, saturation
Brief summary
The purpose of this study is to determine whether breathing high levels of oxygen during surgery affects oxygen levels after surgery. The second purpose of this study is to determine whether giving positive end expiratory pressure PEEP and high oxygen together affects patients oxygen levels after surgery.
Detailed description
This is a randomized, controlled, blinded trial in patients undergoing non-abdominal surgery of the effect of intraoperative increased inspired oxygen used (FiO2\>0.9 vs. FiO2 = 0.3) on non-invasive oxygen saturation (pulse oximetry, SpO2) and amount of required supplemental oxygen in the post-anesthesia care unit (PACU); arterial oxygen partial pressure (PaO2) after 45 minutes in the PACU; room air SpO2 24 hours after surgery, and amount of supplemental oxygen required 24 hours after surgery. The purpose of the study is to determine whether absorption atelectasis induced by use of inspired oxygen concentrations in excess of 90% leads to a higher risk of hypoxemia, as evidenced by room air oxygen values and the need for supplemental oxygen. The objective of this study is to determine whether high inspired oxygen (\>0.8), which has been demonstrated to reduce the risk of surgical site infection in patients undergoing colon surgery and other major surgical procedures has side effects that limit its use to prevent infection in lower risk operations. There are four groups of intraoperative ventilation management in this study. Fi02 0.3 plus PEEP, Fi02 0.3 without PEEP, Fi02 greater than 0.9 plus PEEP 3 to 5 cm of water, Fi02 greater than 0.9 without PEEP.
Interventions
OTHERFiO2 (fraction of inspired oxygen) 0.3 plus PEEP (positive end expiratory pressure) 3 -5 cm water
FiO2 (fraction of inspired oxygen) 0.3 plus PEEP (positive end expiratory pressure) 3-5 cm water
OTHERFiO2 0.3 without PEEP
FiO2 0.3 without PEEP
OTHERFiO2 >0.9 with 3-5 cm water PEEP
FiO2 \>0.9 with 3-5 cm water PEEP
OTHERFiO2 >0.9 without PEEP
FiO2 \>0.9 without PEEP
Sponsors
University of Utah
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
DIAGNOSTIC
Masking
DOUBLE (Subject, Investigator)
Eligibility
Sex/Gender
ALL
Age
18 Years to 70 Years
Healthy volunteers
No
Inclusion criteria
* Patients aged 18-70 years undergoing surgery under general endotracheal anesthesia at the University of Utah Hospital Operating Room and the Huntsman Cancer Hospital Operating room who will be admitted to the hospital for at least 24 hours after surgery
Exclusion criteria
* Major (open) abdominal surgery * Major spine surgery * Craniotomy surgery * Surgeries where electrocautery or laser devices may be used near the airway (eg tracheostomy, oral surgery) because of the risk of fire with high inspired oxygen in these cases * Procedures planned for monitored anesthesia care (MAC) or regional without general anesthesia * Planned airway management with a laryngeal mask airway rather than an endotracheal tube * Procedures planned in the prone position because this increases atelectasis * Planned postoperative intubation * Planned postoperative care in the intensive care unit * Recent (within 3 weeks) chemotherapy because of the increased risk of pulmonary oxygen toxicity * History of bleomycin administration because of the increased risk of pulmonary oxygen toxicity * Diagnosed Obstructive Sleep Apnea with home continuous pulmonary airway pressure (CPAP) use * Home oxygen use * Preoperative room air (RA) SpO2 \<90% * History of spontaneous pneumothorax * Emergency surgery * Pregnancy. Women of child-bearing age are routinely screened for pregnancy urine human chorionic gonadotropin, (HCG) on the morning of surgery. Patients with a positive result will be excluded from the study (and most likely will have their elective surgery cancelled). * Patient refusal
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Oxygen Requirement to Maintain SpO2>90% | 45 min after emergence (tracheal extubation) | Arterial oxygen saturation by pulse oximetry (SpO2) is measured while subject is lying quietly in the post anesthesia care unit (PACU) and breathing room air (RA). Oxygen is added 0.5 liters per min (LPM) at a time to maintain SpO2 \>90%. |
| Oxygen Requirement | 24 hours after tracheal extubation | amount of oxygen (LPM) required to maintain SpO2 \>90% |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Arterial Oxygen Saturation by Pulse Oximetry (SpO2) | 45 min after tracheal extubation | SpO2 measured on room air or minimum supplemental oxygen to keep SpO2\>90% |
| SpO2 Postoperatively | 24 hours after tracheal extubation | SpO2 is measured on room air or minimum oxygen required to keep SpO2\>90% on the ward 24 hours after tracheal extubation. |
Countries
United States
Participant flow
Recruitment details
Recruitment started 06/24/2008 and ended 07/07/2009. Subjects were recruited via the Operating room schedule
Participants by arm
| Arm | Count |
|---|---|
| Fi02 (Fraction of Inspired Oxygen) 0.3 With PEEP 30% oxygen with positive end expiratory pressure (PEEP) | 25 |
| Fi02 0.3 Without PEEP 30% oxygen without PEEP | 25 |
| Fi02 0.9 With PEEP 90% oxygen plus PEEP | 25 |
| Fi02 0.9 Without PEEP 90% oxygen without PEEP | 25 |
| Total | 100 |
Baseline characteristics
| Characteristic | Fi02 0.9 With PEEP | Total | Fi02 0.9 Without PEEP | Fi02 (Fraction of Inspired Oxygen) 0.3 With PEEP | Fi02 0.3 Without PEEP |
|---|---|---|---|---|---|
| Age Continuous | 46 years STANDARD_DEVIATION 15 | 46 years STANDARD_DEVIATION 13 | 46 years STANDARD_DEVIATION 13 | 47 years STANDARD_DEVIATION 13 | 45 years STANDARD_DEVIATION 12 |
| Age, Customized <=18 years | 0 participants | 0 participants | 0 participants | 0 participants | 0 participants |
| Age, Customized >=65 years | 1 participants | 6 participants | 2 participants | 2 participants | 1 participants |
| Age, Customized Between 18 and 65 years | 24 participants | 94 participants | 23 participants | 23 participants | 24 participants |
| Region of Enrollment United States | 25 participants | 100 participants | 25 participants | 25 participants | 25 participants |
| Sex: Female, Male Female | 12 Participants | 55 Participants | 15 Participants | 13 Participants | 15 Participants |
| Sex: Female, Male Male | 13 Participants | 45 Participants | 10 Participants | 12 Participants | 10 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk | EG002 affected / at risk | EG003 affected / at risk |
|---|---|---|---|---|
| deaths Total, all-cause mortality | — / — | — / — | — / — | — / — |
| other Total, other adverse events | 0 / 25 | 0 / 25 | 0 / 25 | 0 / 25 |
| serious Total, serious adverse events | 0 / 25 | 0 / 25 | 0 / 25 | 0 / 25 |
Outcome results
Primary
Oxygen Requirement
amount of oxygen (LPM) required to maintain SpO2 \>90%
Time frame: 24 hours after tracheal extubation
| Arm | Measure | Value (MEDIAN) |
|---|---|---|
| Fi02 (Fraction of Inspired Oxygen) 0.3 With PEEP | Oxygen Requirement | 0.5 liters per min |
| Fi02 0.3 Without PEEP | Oxygen Requirement | 0.5 liters per min |
| Fi02 0.9 With PEEP | Oxygen Requirement | 1.0 liters per min |
| Fi02 0.9 Without PEEP | Oxygen Requirement | 0.5 liters per min |
Primary
Oxygen Requirement to Maintain SpO2>90%
Arterial oxygen saturation by pulse oximetry (SpO2) is measured while subject is lying quietly in the post anesthesia care unit (PACU) and breathing room air (RA). Oxygen is added 0.5 liters per min (LPM) at a time to maintain SpO2 \>90%.
Time frame: 45 min after emergence (tracheal extubation)
| Arm | Measure | Value (MEDIAN) |
|---|---|---|
| Fi02 (Fraction of Inspired Oxygen) 0.3 With PEEP | Oxygen Requirement to Maintain SpO2>90% | 1 liters per minute |
| Fi02 0.3 Without PEEP | Oxygen Requirement to Maintain SpO2>90% | 1 liters per minute |
| Fi02 0.9 With PEEP | Oxygen Requirement to Maintain SpO2>90% | 1 liters per minute |
| Fi02 0.9 Without PEEP | Oxygen Requirement to Maintain SpO2>90% | 1 liters per minute |
Secondary
Arterial Oxygen Saturation by Pulse Oximetry (SpO2)
SpO2 measured on room air or minimum supplemental oxygen to keep SpO2\>90%
Time frame: 45 min after tracheal extubation
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Fi02 (Fraction of Inspired Oxygen) 0.3 With PEEP | Arterial Oxygen Saturation by Pulse Oximetry (SpO2) | 95 percent saturation | Standard Deviation 2 |
| Fi02 0.3 Without PEEP | Arterial Oxygen Saturation by Pulse Oximetry (SpO2) | 96 percent saturation | Standard Deviation 2 |
| Fi02 0.9 With PEEP | Arterial Oxygen Saturation by Pulse Oximetry (SpO2) | 95 percent saturation | Standard Deviation 2 |
| Fi02 0.9 Without PEEP | Arterial Oxygen Saturation by Pulse Oximetry (SpO2) | 95 percent saturation | Standard Deviation 2 |
Secondary
SpO2 Postoperatively
SpO2 is measured on room air or minimum oxygen required to keep SpO2\>90% on the ward 24 hours after tracheal extubation.
Time frame: 24 hours after tracheal extubation
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Fi02 (Fraction of Inspired Oxygen) 0.3 With PEEP | SpO2 Postoperatively | 95 percent saturation | Standard Deviation 2 |
| Fi02 0.3 Without PEEP | SpO2 Postoperatively | 95 percent saturation | Standard Deviation 2 |
| Fi02 0.9 With PEEP | SpO2 Postoperatively | 95 percent saturation | Standard Deviation 2 |
| Fi02 0.9 Without PEEP | SpO2 Postoperatively | 95 percent saturation | Standard Deviation 2 |