None listed
Conditions
Brief summary
BACKGROUND: Extubation failure in brain injured patients is high compared with the expected rates in general ICU patients, and ranges from 15-20%. The rate of reconnection to the ventilator in tracheostomized brain injured patients seems to be even higher. Independent associations between extubation failure and increased mortality have been noted previously, though largely in the medical ICU. Respiratory failure represents the primary reason for reintubation and resumption of mechanical ventilation in both intubated and tracheostomized patients. AIM: We aim to investigate the course of diaphragmatic dysfunction measured by ultrasound in brain injured patients and whether diaphragmatic dysfunction represents the major determinant of ventilatory failure. METHODS: Patients with the following inclusion criteria will be considered eligible: 1) age between 18 and 80, 2) mechanical ventilation for less than 24 hours, 3) ICU admission for intraparenchimal hemorrhage, subacnoid hemorrhage, or traumatic brain injury, 4) requirement of more than 48 hours of mechanical ventilation. Exclusion criteria will be: 1) known diaphragmatic dysfunction, and 2) preexisting decision to limit life support, 3)cervical spine injury, 4) neuromuscular disease (myasthenia gravis, Guillain-Barre´ syndrome, amyotrophic lateral sclerosis); 5) current thoracostomy, pneumothorax, or pneumomediastinum. In all included newly intubated brain injured patients the ultrasonographic measurement of diaphragm will be performed within 24 hours after the start of mechanical ventilation, 48 hours after intubation, 7 days after intubation, during the spontaneous breathing trial (SBT) and after extubation. MEASUREMENTS: Demographic variables, including the Simplified Acute Physiology Score II (SAPS II) will be recorded. Furthermore will be recorded all the parameters associated with a decrease in diaphragm thickness: age, sex, SAPS II, duration of MV, percentage of time in controlled MV modes, use of corticosteroids during ICU stay, sepsis, continued use of neuromuscular blocking agents and aminoglycosides antibiotic use. All patients will be sedated in accordance with our sedation protocol. During SBT, rapid shallow breathing index, Ultrasound evaluation of the diaphragm thikening and excursion will be performed at ICU entrance, 48 hours after intubation, 7 days after intubation, during the spontaneous breathing trial and 48 hours after extubation. Before commencing the study, after one month training, both intra- and inter-observer variability of diaphragm ultrasound recordings in both ventilated patients and non-ventilated volunteers on different time points will be performed and the coefficients of reproducibility for intra-observer variability will be calculated.
Interventions
For one year, we will study diaphragmatic dysfunction measured by ultrasound (excursion and thikening) in all brain injured patients entering the intensive care unit of the "Maggiore della Carita" hospital in Novara. In all included newly intubated brain injured patients the ultrasonographic measurements of diaphragm will be performed within 24 hours after the start of mechanical ventilation in volume controlled mode, 48 hours after intubation, 7 days after intubation, during the spontaneous bre
For one year, we will study diaphragmatic dysfunction measured by ultrasound (excursion and thikening) in all brain injured patients entering the intensive care unit of the "Maggiore della Carita" hospital in Novara. In all included newly intubated brain injured patients the ultrasonographic measurements of diaphragm will be performed within 24 hours after the start of mechanical ventilation in volume controlled mode, 48 hours after intubation, 7 days after intubation, during the spontaneous breathing trial (SBT) and after extubation/tracheostomy during spontaneus breathing. Briefly, ultrasound evaluation of the diaphragm will be performed with the patients in the supine position. Diaphragmatic movement will be measured with a 3.5 MHz US probe placed over one of the lower intercostals spaces in the right anterior axillary line for the right diaphragm and the left midaxillary line for the left diaphragm using an ultrasound machine. The liver or spleen will be used as a window for each hemidiaphragm. A two- dimensional mode will be used to find the best approach and to select the exploration line of each hemidiaphragm. With the probe fixed on the chest wall during respiration, the ultrasound beam will be directed to the hemidiaphragmatic domes at an angle of not inferior to 70 degree. During inspiration, the normal diaphragm contracts and moves caudally toward the transducer; this is recorded as an upward motion of the M-mode tracing. The amplitude of excursion is measured on the vertical axis of the tracing from the baseline to the point of maximum height of inspiration on the graph. Four measurements will be recorded and averaged for each side. All measurements will be performed during tidal breathing at 6–12 mL per kg, excluding smaller or deeper breaths. Ultrasonographic diaphragmatic disfunction will be diagnosed if an excursion will be less than 10 mm or negative, the latter indicating paradoxic diaphragmatic movement. Diaphragm thickness (tdi) will be measured using a 7–10 MHz linear ultrasound probe set to B mode. The right hemidiaphragm will be imaged at the zone of apposition of the diaphragm and rib cage in the midaxillary line between the 8th and 10th intercostal spaces. The tdi will be measured at end-expiration and end-inspiration. The per cent change in tdi between end-expiration and end-inspiration will be calculated as (tdi end-inspiration-tdi end-expiration/tdi end-expiration)×100. The per cent change in tdi for each patient represented the mean of four breaths.
Sponsors
Universita del Piemonte Orientale Amedeo Avogadro
Eligibility
Sex/Gender
All
Age
18 Years to 80 Years
Healthy volunteers
No
Inclusion criteria
Patients with the following inclusion criteria will be considered eligible: 1) age between 18 and 80, 2) mechanical ventilation for less than 24 hours, 3) ICU admission for intraparenchimal hemorrhage, subacnoid hemorrhage, or traumatic brain injury, 4) expected requirement of more than 48 hours of mechanical ventilation.
Exclusion criteria
Exclusion criteria will be: 1) known diaphragmatic dysfunction, and 2) preexisting decision to limit life support, 3)cervical spine injury, 4) neuromuscular disease (myasthenia gravis, Guillain-Barre´ syndrome, amyotrophic lateral sclerosis); 5) current thoracostomy, pneumothorax, or pneumomediastinum.
Outcome results
None listed