The Cerebral-Respiratory Interaction During Spontaneous Breathing Ventilation in Neurosurgical Patients (CeRes-SB)

• Conditions: Mechanical Ventilation Complication; Respiratory Complication; Neurological Complication
• Interventions: Other: Mechanically ventilated neurosurgical patients

• Registration Number: NCT05363098
• Lead Sponsor: Uppsala University

Brief Summary

Mechanical ventilation (MV) is a life-saving supportive therapy and one of the most common interventions implemented in intensive care.

To date, only the inspiratory phase of breathing has been extensively investigated, and new MV methods have been implemented to reduce its harmful effects. Despite this, lung injury still occurs and propagates, causing multiorgan failure and patient deaths. The expiratory phase is considered unharmful and is not monitored or assisted during MV. In animal experiments, we recently showed that the loss of diaphragmatic contraction during expiration can harm the lungs during MV. During mechanical ventilation, the expiratory phase of breathing is completely disregarded. However, in all conditions that promote lung collapse, peripheral airways gradually compress and close throughout the expiration, potentially worsening lung injury.

This cyclical lung collapse and consequent air-trapping may have an impact on the Starling resistor mechanisms that regulate venous return from the brain, potentially affecting cerebral perfusion and intracranial pressure.

This study will investigate the incidence and the consequences of an uncontrolled expiration and expiratory lung collapse in spontaneously breathing critically ill neurosurgical patients during 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, on a daily bases during assisted mechanical ventilation.

Detailed Description

Not available

Study Timeline

• Study First Submitted: 2022-04-27
• Status Verified: 2022-05
• Study Start: 2022-05
• Study First Submitted QC: 2022-05-02
• Last Update Submitted: 2022-05-02
• Study First Posted: 2022-05-05
• Last Update Posted: 2022-05-05
• Primary Completion: 2022-12
• Study Completion: 2023-05

Recruitment & Eligibility

• Status: UNKNOWN
• Sex: All
• Target Recruitment: 30

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.

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Arm && Interventions

Group	Intervention	Description
Mechanically ventilated neurosurgical patients	Mechanically ventilated neurosurgical patients	Observational study in mechanically ventilated neurosurgical patients

Primary Outcome Measures

Name	Time	Method
Correlation between uncontrolled expiration and intracranial pressure	During the period of assisted mechanical ventilation, an average of 14 days	The influence of an uncontrolled expiration (defined by expiratory flow, expiratory EAdi and thoracic impedance) on intracranial pressure in neurosurgical patients.
Incidence of uncontrolled expiration	during the period of assisted mechanical ventilation, an average of 14 days	The incidence of uncontrolled expiration and consequent expiratory lung collapse (determined by changes in expiratory flow and time constant) during assisted ventilation in neurosurgical patients.

Secondary Outcome Measures

Name	Time	Method
90-days mortality from intensive care unit admission	90 days after hospital discharge	Correlation between lung collapse and 90-days mortality
Number of days of mechanical ventilation	At ICU discharge, an average of 20 days	Correlation between lung collapse and days of mechanical ventilation
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)
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