The Use of Constant-flow Technique for Determining the Lower Inflexion Point of Pressure-volume Curve and Intrinsic PEEP During One-lung Ventilation

NeuroTherapia, Inc.

Status: Withdrawn

Conditions: One Lung Ventillation (OLV); Zero End-expiratory Pressure (ZEEP); Positive End Expiratory Pressure (PEEP); Two Lung Ventillation (TLV)

Treatments: Other: two lung ventilation (TLV); Other: One lung ventilation (OLV) with positive end-expiratory pressure (PEEP); Other: one lung ventilation (OLV) without PEEP

Study type: Interventional

Funder types: Other

Identifiers

NCT01532245

DEOEC RKEB/IKEB 3504-2011

Details and patient eligibility

About

One method for treating intraoperative hypoxia during one-lung ventilation (OLV) is application of PEEP to the dependent lung. However, only a minority of patients benefit from this maneuver. The effect of applied PEEP on oxygenation depends on the relation between the total end-expiratory pressure and the lower inflexion point (LIP) of pressure-volume curve (1). LIP during OLV can be determined with super-syringe technique, but is too complicated for routine operating room use. An alternative is the constant-flow method which is easy and widely used in intensive care settings (2). The investigators goal was to confirm that the constant-flow method as applied by an intensive care ventilator works during OLV.

Methods: After IRB approval and written, informed consent, data were obtained from 20 patients during OLV for thoracic surgery who were ventilated with an AVEA (VIASYS Healthcare) critical-care ventilator. During two-lung ventilation (TLV) and OLV 8 ml•kg-1 tidal volume was used. During OLV, ventilation periods of ten minutes, with and without 5 cmH2O PEEP were alternated. During each period, the investigators recorded arterial blood partial pressures, respiratory and hemodynamic values, intrinsic PEEP (PEEPi), and LIP. PEEPi and LIP were determined using the automatic mode of the ventilator; specifically, LIP was determined with a continuous flow of 3L/minute.

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion and exclusion criteria

Inclusion Criteria:

• thoracic surgery lung ventillation

Trial design

Primary purpose: Other

Allocation: Non-Randomized

Interventional model: Single Group Assignment

Masking: None (Open label)

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0 participants in 3 patient groups

two-lung ventilation (TLV)

Active Comparator group

Description:

During two-lung ventilation (TLV) and OLV 8 ml•kg-1 tidal volume was used.

Treatment:

Other: two lung ventilation (TLV)

one lung ventillation (OLV) without PEEP

Active Comparator group

Description:

During OLV, ventilation periods of ten minutes, with and without 5 cmH2O positive end-expiratory pressure (PEEP) were alternated.

Treatment:

Other: one lung ventilation (OLV) without PEEP

one lung ventilation (OLV) with PEEP

Active Comparator group

Description:

During OLV, ventilation periods of ten minutes, with and without 5 cmH2Opositive end-expiratory pressure (PEEP) were alternated

Treatment:

Other: One lung ventilation (OLV) with positive end-expiratory pressure (PEEP)