The Effect of Different I:E Ratio on Gas Exchange of Patients Undergoing One-lung Ventilation for Lung Surgery

Samsung Medical Center

Status: Completed

Conditions: Lung Cancer; Gas Exchange; One Lung Ventilation; Inverse-ratio Ventilation

Treatments: Other: Conventional I:E ratio; Other: I:E = 1:1 ratio

Study type: Interventional

Funder types: Other

Identifiers

NCT01540201

2011-12-033-002

Details and patient eligibility

About

Pulmonary gas exchange disturbance is a common anesthetic problem during one-lung ventilation (OLV) for thoracic surgery. The inverse-ratio ventilation (IRV), which prolongs the inspiratory time greater than expiratory time, can be applied for adult respiratory distress syndrome. The effect of IRV is to improve gas-exchange status by increasing mean airway pressure and alveolar recruitment. We tried to evaluate the effect of IRV during OLV with lung protective strategy.

Full description

Pulmonary gas exchange disturbance is a common anesthetic problem during one-lung ventilation (OLV) for thoracic surgery. Continuous positive airway pressure or positive end-expiratory pressure are usually applied to improve this disorder including hypoxia, but these methods are not enough. The inverse-ratio ventilation (IRV), which prolongs the inspiratory time greater than expiratory time, can be applied for adult respiratory distress syndrome. The effect of IRV is to improve gas-exchange status by increasing mean airway pressure and alveolar recruitment. The application of IRV during OLV has not been performed to our knowledge, and there is a possibility of IRV to improve oxygenation during OLV. There is a possibility of increase of auto-PEEP, or air trapping in subjects with chronic obstructive pulmonary disease, but this kind of auto-PEEP can be overcome by external PEEP. Therefore, we tried to evaluate the effect of IRV during OLV with lung protective strategy.

Enrollment: 110 patients

Sex: All

Ages: 20 to 70 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• patients undergoing elective lung lobectomy surgery.
• the duration of one-lung ventilation is more than one hour.
• subjects with more than twenty years old.

Exclusion criteria

• subjects with past history of pneumothorax, asthma
• Age under 20, more than 70 years.
• Patients with ischemic heart disease, valvular heart disease
• patients with hemodynamic unstability

Trial design

110 participants in 2 patient groups

1:2 group

Active Comparator group

Description:

conventional I:E ratio group, inspiratory time : expiratory time = 1:1

Treatment:

Other: Conventional I:E ratio

1:1 group

Experimental group

Description:

inspiratory time : expiratory time = 1:1

Treatment:

Other: I:E = 1:1 ratio