Effects of Spontaneous Breathing Activity on Atelectasis Formation During General Anaesthesia

NCT01073917 | Completed

• 1 other identifier: EK375122009
• Study Type: interventional
• Target: 30
• Locations: 1 country
• Sites: 1

Brief Summary

Atelectasis and redistribution of ventilation towards non-dependent lung zones are a common side effects of general anesthesia. Spontaneous breathing activity (SBA) during mechanical ventilation may avoid or reduce atelectasis, improving arterial oxygenation; however, it is unclear whether these effects play a significant role during general anesthesia in patients with healthy lungs. Earlier studies on ventilation during general anesthesia had to rely on computed tomography (CT) findings. Recent advances in lung imaging technology allow to assess the regional aeration of the lungs continuously and non-invasive by electrical impedance technology (EIT). In this work, we will use the EIT to assess ventilation changes from the time before induction of anesthesia until discharge from the post-anesthesia care unit. Our main focus is the difference caused by pure positive pressure ventilation (PCV) and assisted spontaneous breathing (pressure support ventilation, PSV). Our findings would improve our understanding of the physiology of the lungs during general anesthesia and would help to improve the standards of respiratory care during anesthesia

Conditions

Atelectasis

Keywords

Ventilation; General Anesthesia; electrical impedance tomography; pressure support; spontaneous breathing; laryngeal mask; Patients who are scheduled for elective knee or ankle surgery

Outcome Measures

Primary Outcomes (1)

• Regional ventilation at the end of anaesthesia and at discharge from PACU compared to baseline values obtained before induction

  Before, during and after anesthesia

Secondary Outcomes (1)

• Differences in spirometry values, oxygenation in the PACU (measured as SpO2 at room air), breathing effort

  Before, during and after anesthesia

Study Arms (3)

Spontaneous Breathing

OTHER

Patients will be breathing spontaneously during anesthesia

Other: Spontaneous Breathing

Pressure controlled ventilation

OTHER

Patients in the PPV group will be ventilated by pressure control (tidal volume 8-10 ml/kg, frequency 10-14, I:E 1:1, no PEEP, target CO2 4.5 kPa).

Other: Pressure Controlled Ventilation

Pressure Support Ventilation

OTHER

The patients in the PSV group will breathing spontaneously on the ventilator with assistance by inspiratory support pressure. The support pressure will be adjusted to achieve a tidal volume of 8-10 ml/kg.

Other: Pressure Support Ventilation

Interventions

Spontaneous Breathing OTHER

Spontaneous Breathing

Pressure Controlled Ventilation OTHER

Pressure controlled ventilation

Pressure Support Ventilation OTHER

Pressure Support Ventilation

Eligibility Criteria

• Age: 18 Years - 65 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Patients (age 18-65) scheduled for elective knee or ankle surgery under general anaesthesia with an LMA with an expected duration of at least 60 minutes.

You may not qualify if:

• Pregnancy,
• Pulmonary diseases (e.g. Asthma, COPD),
• Implanted pacemaker or AICD,
• Inability to communicate or understand the risks of the study,
• Contraindications for an LMA (e.g. obesity, reflux),
• Deformities of the thorax,
• Failure to place an LMA.

Sponsors & Collaborators

• Technische Universität Dresden: lead

Study Sites (1)

University Hospital Carl-Gustav-Carus

Dresden, Saxony, 01307, Germany

Location

Related Links

• Department of Anesthesia and Intensive Care Medicine, University Hospital Dresden, Germany

MeSH Terms

Conditions

Pulmonary Atelectasis; Respiratory Aspiration

Condition Hierarchy (Ancestors)

Lung Diseases; Respiratory Tract Diseases; Respiration Disorders; Pathologic Processes; Pathological Conditions, Signs and Symptoms

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: PARTICIPANT
• Purpose: SUPPORTIVE CARE
• Intervention Model: PARALLEL
• Sponsor Type: OTHER

Study Record Dates

• First Submitted: February 22, 2010
• First Posted: February 23, 2010
• Study Start: March 1, 2010
• Primary Completion: October 1, 2010
• Study Completion: October 1, 2010
• Last Updated: October 29, 2010

Record last verified: 2010-10

Locations

DE (1)