High Tidal Volume Induces Inflammation In Normal Lungs (Normallung)

Mechanical Ventilation With High Tidal Volume Induces Inflammation In Patients Without Lung Disease

Objective: To compare the effects of a protective versus a conventional ventilatory strategy, on systemic and in lung production of tumor necrosis factor-alpha (TNF-alpha) and interleukin-8 (IL-8) in patients without lung disease.

Hypothesis: High tidal volumes induce inflammation in patients without lung disease Design: Prospective control-randomized study. Patients and Setting: Twenty patients without lung disease and submitted to mechanical ventilation admitted to one trauma and one general adult intensive care unit of two different university hospitals.

Interventions: Patients were randomized to receive mechanical ventilation either with tidal volume (VT) of 10-12 ml/kg predicted body weight (high VT group) or with VT of 5-7 ml/kg predicted body weight (low VT group) with an O2 inspiratory fraction (FIO2) enough to keep arterial oxygen saturation > 90% with positive end-expiratory pressure (PEEP) of 5 cmH2O during 12 hours after admission to the study.

Study Overview

• Status: Completed
• Conditions: Mechanically Ventilated Patients; Normal Lungs
• Intervention / Treatment: Procedure: Low tidal volume; Procedure: Low tidal volume; Other: low tidal volume

• Study Type: Interventional
• Enrollment (Anticipated): 20
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Brazil
  • RS
    • Porto Alegre, RS, Brazil, 900000
      • Complexo Hospitalar Santa Casa
    • Porto Alegre, RS, Brazil, 90000
      • Hospital de Pronto Socorro

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 16 years and older (ADULT, OLDER_ADULT, CHILD)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

1. age ≥ 16 years;
2. anticipated survival > 24 hours;
3. need for mechanical ventilation for at least 12 hours and
4. hemodynamic stability (MAP>65 mmHg, HR<100 beats/min, diuresis > 1 ml/kg/h, no catecholamine requirement or fluid challenge).

Exclusion Criteria:

1. history of any lung disease, use of immunosuppressive medication, recent infections, previous thromboembolic disease, recent ventilatory support, and participation in another clinical trial. Absence of lung disease was defined by the following clinical criteria: (a) no evidence of respiratory infection (white blood cell count <10x103/µl, temperature > 380C, purulent sputum), (b) normal chest roentgenogram, (c) PaO2/FIO2 ratio > 300, (d) and a normal clinical respiratory history.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: SUPPORTIVE_CARE
• Allocation: RANDOMIZED
• Masking: NONE

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
NO_INTERVENTION: high VT group
EXPERIMENTAL: Low tidal volume	Procedure: Low tidal volume; twenty patients were randomly (opaque sealed envelopes) assigned to receive mechanical ventilation in volume-controlled mode either with VT of 10-12 ml/kg predicted body weight (high VT group, n=10) or with VT of 5-7 ml/kg predicted body weight (low VT group, n=10) with an inspiratory fraction of oxygen (FIO2) set at the minimal level at which an arterial oxygen saturation of > 90% and minimal PEEP (4-5cmH2O). The predicted body weight of male patients was calculated as equal to 50+0.91(centimeters of height-152.4); that of female patients was calculated as equal to 45.5+0.91(centimeters of height-152.4).; Procedure: Low tidal volume; Immediately after ICU admission, once all inclusion and exclusion criteria were met and consent obtained, twenty patients (16 men, 4 women, median age of 49 yrs) were randomly (opaque sealed envelopes) assigned to receive mechanical ventilation in volume-controlled mode either with VT of 10-12 ml/kg predicted body weight (high VT group, n=10) or with VT of 5-7 ml/kg predicted body weight (low VT group, n=10) with an inspiratory fraction of oxygen (FIO2) set at the minimal level at which an arterial oxygen saturation of > 90% and minimal PEEP (4-5cmH2O). The predicted body weight of male patients was calculated as equal to 50+0.91(centimeters of height-152.4); that of female patients was calculated as equal to 45.5+0.91(centimeters of height-152.4); Other: low tidal volume; tidal volume of 5-7 ml/kg predicted body weight

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Lung cytokines in mechanically ventilated patients	30 months

Collaborators and Investigators

• Sponsor: Federal University of Rio Grande do Sul
• Collaborators: Programa de Pós-Graduação em Clínica Médica; Faculdade de Medicina

Study record dates

Study Registration Dates

• First Submitted: July 8, 2009
• First Submitted That Met QC Criteria: July 8, 2009
• First Posted (ESTIMATE): July 9, 2009

Study Record Updates

• Last Update Posted (ESTIMATE): July 9, 2009
• Last Update Submitted That Met QC Criteria: July 8, 2009
• Last Verified: July 1, 2009

More Information

Terms related to this study

• Keywords: Mechanical ventilation; Interleukin-8; Tumor necrosis factor-alpha; Ventilator-associated lung injury; Low tidal volume ventilation; Normal lungs
• Additional Relevant MeSH Terms: Pathologic Processes; Inflammation
• Other Study ID Numbers: normal lung - V1; CAPES-PROF - UFRGS