Lung Injury, Mechanical Ventilation Complication, Neurological Disorder
Conditions
Brief summary
The impact of mechanical ventilation on intracranial perfusion is still not completely clarified. It is often assumed that raising airway pressure will invariably elevate the intracranial pressure, but this is not always the case. The effects of airway pressure on intracranial pressure can depend on several factors, and among others, an uncontrolled expiration and consequent lung collapse may have an influence on cerebral perfusion. This study will investigate the incidence and the consequences of an uncontrolled expiration and expiratory lung collapse in critically ill neurosurgical patients during controlled mechanical ventilation. Electrical impedance tomography measurements , oesophagus and gastric pressure, electrical activity of the diaphragm and intracranial pressure will be acquired in a synchronised manner during controlled mechanical ventilation. Moreover, airway opening pressure, expiratory flow limitation and recruitment/inflation ratio will be determined during controlled mechanical ventilation, on a daily bases until the patient recover his/her own spontaneous breathing.
Interventions
Observational study where respiratory variables and intracranial pressure will be measured during mechanical ventilation and during specific respiratory manoeuvres. No intervention is planned.
Sponsors
Uppsala University
Study design
Observational model
COHORT
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
The patients will be included within 48 hours from initiation of mechanical ventilation and insertion of an external ventricular drainage catheter Inclusion Criteria: * Age \>18 years; * MV expected for more than 72 hours; * Not pregnant; * Informed consent from patient or next of kin.
Exclusion criteria
* Previously demonstrated paralysis of the diaphragm or know pathology of the phrenic nerve or neuromuscular disorder, * Chest tube, * Patients with clinical conditions that contraindicate the insertion of esophageal/gastric catheters (e.g., esophagus rupture, esophageal bleeding), * Pacemaker and/or implantable cardioverter defibrillator, these last being a contraindication for EIT. * Hemicraniectomy. In case of late hemicraniectomy (after patient inclusion), the patient will drop-out from the study. Relative contraindication: in case of skull base fracture the patient can be included only if oesophageal/gastric and NAVA catheters can be inserted orally.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| The incidence of lung collapse | during the period of controlled mechanical ventilation, an average of 14 days | The incidence of an uncontrolled expiration and consequent expiratory lung collapse (determined by expiratory flow limitation, airway opening pressure and expiratory thoracic impedance) increased chest-wall elastance in neurosurgical patients. |
| Correlation between lung recruitability and intracerebral pressure | during the period of controlled mechanical ventilation, an average of 14 days | The influence of lung recruitability (determined by recruitment/inflation ratio and changes of thoracic impedance) on intra cerebral pressure in neurosurgical patients. |
| Correlation between lung collapse and intracerebral pressure | during the period of controlled mechanical ventilation, an average of 14 days | The correlation between an uncontrolled expiration (determined by expiratory flow limitation, airway opening and expiratory thoracic impedance), increased chest-wall elastance and intracranial pressure in neurosurgical patients. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Intensive care unit (ICU) and hospital length of stay (LOS); | At ICU/hospital discharge, an average of 30 days | Correlation between lung collapse and LOS |
| 30-day and 90-days neurological and functional outcomes | 90 days after hospital discharge | Correlation between lung collapse and 30-day and 90-days neurological and functional outcomes (Disability Rating Scale, clinical frailty score, Glasgow Outcome Scale) |
| Number of days of mechanical ventilation | At ICU discharge, an average of 20 days | Correlation between lung collapse and days of mechanical ventilation |
| 90-days mortality from intensive care unit admission | 90 days after hospital discharge | Correlation between lung collapse and 90-days mortality |
Contacts
Primary ContactMariangela Pellegrini, MD, PhD
Outcome results
None listed