Pulmonary Ventilation; Newborn, Abnormal
Conditions
Brief summary
Mechanical ventilation is indispensable for most of surgical interventions but can induce lung injury even in pulmonary healthy patients. This can lead to postoperative pulmonary complications. These adverse effects could be prevented by a better monitoring of intraoperative lung function. Electrical impedance tomography is able to visualize aeration within the lung in real time. The planned study investigates the influence of different levels of positive endexspiratory pressure and different tidal volumes on the aeration.
Detailed description
Available perioperative parameters to set mechanical ventilation parameters represent only global lung function. But to reduce postoperative pulmonary complications induced by mechanical ventilation a better monitoring of intraoperative lung function seems to be crucial, that provides more regional information of lung collapse or over distention. By application of small currents via electrodes around the thorax and measuring of the resultant resistance the electrical impedance tomography (EIT) can determine the level of aeration of the lung in a cross sectional plane. The EIT device used in this study calculates the percentage of the investigated lung area that can be defined as over distended or collapsed respectively. In these sections the change of resistance within a respiration cycle is reduced compared to well ventilated areas are therefore called silent spaces. Silent spaces located ventral are termed non-dependent (NSS) and silent spaces located dorsal are termed dependent (DSS). Based on this information the clinician is able to set the respirator in a more lung protective manor. To better understand the influence of positive endexspiratory pressure (PEEP) and tidal volume (Vt) on reginal lung function we are going to carry out the presented study. 40 patients undergoing robot assisted prostatectomy should be enrolled in a study that consists of two phases. In the first phase 20 patients are ventilated with constant PEEP (10mbar) and in ten patients each the Vt is set to 5 or 12ml/kg ideal body weight. In the second phase in further 20 patients the Vt is set to 8ml/ kg ideal bodyweight and the PEEP is 3 or 12mbar in one half of the patients. Under the different ventilation settings the NSS and DSS, the oxygenation index and lung compliance will be investigated.
Interventions
PROCEDUREConstant PEEP - low tidal volume
The respirator is set according to study protocol
PROCEDUREConstant PEEP - high tidal volume
The respirator is set according to study protocol
PROCEDUREconstant tidal volume - low PEEP
The respirator is set according to study protocol
PROCEDUREconstant tidal volume - high PEEP
The respirator is set according to study protocol
Sponsors
Universitätsklinikum Hamburg-Eppendorf
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
SINGLE (Subject)
Intervention model description
40 patients are to be investigated during the project. In phase one 20 patients are ventilated with constant PEEP of 10mbar and the tidal volume is set to 4-5ml/kg IBW or 8-10ml/kg IBW respectively. In phase two further 20 patients are ventilated with a constant tidal volume of 8ml/kg IBW and the PEEP is set to 3mbar or 12mbar respectively.
Eligibility
Sex/Gender
MALE
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* over 18 years of age * scheduled for robot assisted prostate ectomy
Exclusion criteria
* body mass index \>35 kg/m² * chronic obstructive lung disease (GOLD III or IV) * obstructive sleep apnoe syndrome * planned or unplanned admission to intensive care unit for prolonged ventilation * mechanical ventialtion within the last 30 days * lung operation in the past * other lung disease that impairs activity
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change of dependent silent spaces (DSS) and non-dependent silent spaces (NSS) | measurement of DSS and NSS are carried out prior to induction of anesthesia, 10 minutes after induction, 30 minutes after after installation of capnoperitoneum, 10 minutes after skin closure, 15 minutes after arrival at the PACU | The change of silent spaces under different ventilator settings during surgery is investigated. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Oxygenation index | prior to induction of anesthesia, 10 minutes after induction, 30 minutes after installation of capnoperitoneum, 10 minutes after skin closure, 15 minutes after arrival at the PACU | The partial pressure of oxygen is determined at every point of measurement and the value is devided by inspiratory oxygen fraction |
| complinace of the respiratory system | 10 minutes after induction, 30 minutes after capnoperitoneum applied, 10 minutes after skin closure | The compliance of the respiratory system (ml/mbar) is mesured by the respirator during mechanical ventilation |
Other
| Measure | Time frame | Description |
|---|---|---|
| postoperative pulmonary complicaitons | postoperative pulmonary complications apearing within 7 days after surgery | postoperative complications like pneumonia, reintubation and need for non-invasive ventilation are recorded |
Countries
Germany
Contacts
Primary ContactAlexander März, MD
Backup ContactDaniel A Reuter, MD
Outcome results
None listed