Non-dependent Lung High Frequency Positive Pressure Ventilation (HFPPV) and Right Ventricular Function

NCT ID: NCT01019993

Last Updated: 2010-05-28

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: PHASE1
• Total Enrollment: 33 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2004-02-29
• Study Completion Date: 2007-02-28

Brief Summary

The investigators hypothesized that the application of volume-controlled HFPPV to the non-dependent lung during one-lung ventilation (OLV) for thoracotomy in patients with good pulmonary functions and mild-to-moderate pulmonary dysfunction may provide preservation of the right ventricular (RV) function, adequate oxygenation and optimum surgical conditions.

The investigators evaluated the effects of IL-HFPPV on RV ejection fraction (REF), RV end-diastolic volume (RVEDVI), RV stroke work (RVSWI), pulmonary vascular resistance (PVRI), and stroke volume (SVI) indices, oxygen delivery (DO2) and uptake (VO2), shunt fraction (Qs: Qt), and surgical field conditions during OLV for thoracotomy in patients with good and mild-to-moderate impaired pulmonary functions.

Detailed Description

One-lung ventilation (OLV) provides an adequate operative field, but is opposed by the induced hypoxic pulmonary vasoconstriction (HPV) in the non-ventilated lung. It may preserve overall oxygen delivery, however with deleterious increase in shunt fraction and pulmonary vascular resistance.1-2Right ventricular (RV) overload resulting from these increases in its afterload influences postoperative morbidity and mortality. Intrinsic positive end-expiratory pressure (PEEPi) occurs frequently during OLV for thoracic surgery in the dependent lung of patients with pulmonary hyperinflation as opposed to patients with normal pulmonary function.3 The different approaches for the correction of hypoxemia during OLV may require some degree of recruitment of the non-dependent lung (IL), with different maneuvers such as the application of continuous positive pressure ventilation (CPAP) or high frequency jet ventilation (HFJV) to the non-dependent lung. These recruitment strategies, although they may improve arterial saturation, may concurrently decrease cardiac output, therefore having contradictory effects on overall oxygen delivery.4-6 Gas trapping may occur with increased ventilatory frequency during HFJV. This may impair RVEF through the increases in RV afterload.7 Therefore, the use of high frequency positive pressure ventilation (HFPPV) using tidal volumes just greater than the dead space increases arterial oxygen tension (PaO2) and the carbon dioxide excretion (VCO2) linearly with increasing peak airway pressure.8 We hypothesized that the application of volume-controlled HFPPV to the non-dependent lung during OLV for thoracotomy in patients with good pulmonary functions and mild-to-moderate pulmonary dysfunction may provide preservation of the RV function, adequate oxygenation and optimum surgical conditions.

We evaluated the effects of IL-HFPPV on RV ejection fraction (REF), RV end-diastolic volume (RVEDVI), RV stroke work (RVSWI), pulmonary vascular resistance (PVRI), and stroke volume (SVI) indices, oxygen delivery (DO2) and uptake (VO2), shunt fraction (Qs: Qt), and surgical field conditions during OLV for thoracotomy in patients with good and mild-to-moderate impaired pulmonary functions.

Conditions

Lung Diseases; Esophageal Diseases

Keywords

Thoracotomy; one lung ventilation; HFPPV; right ventricular function.

Study Design

• Allocation Method: NON_RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: TREATMENT
• Blinding Strategy: QUADRUPLE

Study Groups

good pulmonary functions (group N)

The patients were allocated if they have forced vital capacity (FVC %) and/or forced expiratory volume in 1 sec (FEV1%) of 80% of predicted or more

Group Type: ACTIVE_COMPARATOR

conventional OLV followed with IL-HFPPV

Intervention Type: PROCEDURE

The patients' lungs were mechanically ventilated with intermittent positive pressure ventilation using fraction of inspired oxygen (FiO2) of 0.5 in air, tidal volume (VT) of 8 mL/kg, inspiratory to expiratory \[I: E\] ratio of 1:2.5, zero positive end-expiratory pressure (PEEP), respiratory rate (R.R) was adjusted to achieve an arterial carbon dioxide tension (PaCO2) 35-45 mm Hg and peak inspiratory pressures were limited to 35 cm H2O. After pleurotomy, OLV was initiated with the same ventilatory settings for the dependent lung. After 30 min, the non-dependent collapsed lung was ventilated using HFPPV mode (IL-HFPPV) with another identical ventilator, with an internal circuit of low compliance, using FiO2 of 0.5 in air, VT 3 mL/kg, I: E ratio \<0.3 and R.R 60 breaths/min.

pulmonary dysfunction (group PD)

The patients were allocated if they have FVC and/or FEV1 of 50%-79% of predicted

Group Type: ACTIVE_COMPARATOR

conventional OLV followed with IL-HFPPV

Intervention Type: PROCEDURE

The patients' lungs were mechanically ventilated with intermittent positive pressure ventilation using fraction of inspired oxygen (FiO2) of 0.5 in air, tidal volume (VT) of 8 mL/kg, inspiratory to expiratory \[I: E\] ratio of 1:2.5, zero positive end-expiratory pressure (PEEP), respiratory rate (R.R) was adjusted to achieve an arterial carbon dioxide tension (PaCO2) 35-45 mm Hg and peak inspiratory pressures were limited to 35 cm H2O. After pleurotomy, OLV was initiated with the same ventilatory settings for the dependent lung. After 30 min, the non-dependent collapsed lung was ventilated using HFPPV mode (IL-HFPPV) with another identical ventilator, with an internal circuit of low compliance, using FiO2 of 0.5 in air, VT 3 mL/kg, I: E ratio \<0.3 and R.R 60 breaths/min.

Interventions

conventional OLV followed with IL-HFPPV

The patients' lungs were mechanically ventilated with intermittent positive pressure ventilation using fraction of inspired oxygen (FiO2) of 0.5 in air, tidal volume (VT) of 8 mL/kg, inspiratory to expiratory \[I: E\] ratio of 1:2.5, zero positive end-expiratory pressure (PEEP), respiratory rate (R.R) was adjusted to achieve an arterial carbon dioxide tension (PaCO2) 35-45 mm Hg and peak inspiratory pressures were limited to 35 cm H2O. After pleurotomy, OLV was initiated with the same ventilatory settings for the dependent lung. After 30 min, the non-dependent collapsed lung was ventilated using HFPPV mode (IL-HFPPV) with another identical ventilator, with an internal circuit of low compliance, using FiO2 of 0.5 in air, VT 3 mL/kg, I: E ratio \<0.3 and R.R 60 breaths/min.

Intervention Type: PROCEDURE

Other Intervention Names

KONTRON ABT 5300 ventilator, UK

Eligibility Criteria

Inclusion Criteria

• Thirty-three patients ASA physical status II-III) scheduled for elective open thoracic surgery were prospectively included in this study at the authors' cardiothoracic center. Approval of the institutional ethical committee and informed written consent was obtained specifically for use of pulmonary artery catheter which is not routinely used in thoracic procedures at the authors' center.

Exclusion Criteria

• Patients with decompensated cardiac (> New York Heart Association II), pulmonary (vital capacity or FEV1% < 50% of the predicted values), hepatic, and renal diseases, arrhythmias, pulmonary hypertension (mean pulmonary artery pressure (MPAP) > 30 mm Hg), and previous history of pneumonectomy, bilobectomy or lobectomy.

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 60 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

Mansoura University

OTHER

Sponsor Role: collaborator

King Faisal University

OTHER

Sponsor Role: lead

Responsible Party

Anaesthesia and Surgical ICU, Faculty of Medicine, Mansoura University, Egypt (current affiliation: Department of Anaesthesia and Surgical ICU, Faculty of Medicine, King Faisal University, Dammam, KSA)

Principal Investigators

Mohamed R El Tahan, M.D.

Role: PRINCIPAL_INVESTIGATOR

Anaesthesia and Surgical ICU, Faculty of Medicine, Mansoura University, Egypt (current affiliation: Department of Anaesthesia and Surgical ICU, Faculty of Medicine, King Faisal University, Dammam, KSA

Reda A. Hamad, M.D.

Role: STUDY_CHAIR

Cardiothoracic Unit, Faculty of Medicine, Mansoura University, Egypt (current affiliation: Prince Sultan Cardiac Centre, Riyadh, KSA

Locations

Cardiothoracic Unit, Faculty of Medicine, Mansoura University, Egypt

Al Mansurah, DK, Egypt

Countries

Egypt

Other Identifiers

39-01-2004

Identifier Type: -

Identifier Source: org_study_id