This study aims to assess whether the degree of diaphragm excursion and diaphragm thickening measured by ultrasound during a weaning trial may be used to predict successful weaning from mechanical ventilation in patients with sepsis in intensive care unit

After being informed about the study and giving written informed consent, Intubated and mechanically ventilated patients with sepsis on admission and fulfilling criteria of weaning from mechanical ventilation (MV), will undergo diaphragm ultrasound during spontaneous breathing trial on T-piece. We will measure diaphragm excursion (DE), diaphragm thickness (DT) and calculate diaphragm thickness fraction (DTF):

DT during inspiration - DT during expiration / DT during expiration

According to weaning outcome, patients will be divided into 2 groups:

• Successful weaning group
• Weaning failure group

By statistical analysis we will define the cut off value and area under curve (AUC) for DE and DTF and we can confirm if DE and DTF using ultrasound can be used as predictors for weaning from MV or not

Inclusion Criteria:

• Patients of both sexes, aging 18 - 60 years after written informed consent
• Patients with sepsis on admission according to the new sepsis definition in 2016 (life-threatening organ dysfunction due to a dysregulated host response to infection)
• Hemodynamically stable without or with low dose support
• Patients on mechanical ventilation for at least 48 hours and not more than 1 week
• Patients ready for start of weaning protocol, fully conscious, on continuous positive airway pressure (CPAP) mode with positive end expiratory pressure (PEEP) 3-5 Centimetre water (CmH2O), Pr. Supp. <15 CmH2O, Fio2 less than 60%, Respiratory rate less than 35 breath/min, partial oxygen pressure (PO2)/FIO2 >200, Rapid Shallow Breathing Index (RSBI) is less than 105

Exclusion Criteria:

• Patients aged less than 18 years or more than 60 years old
• Patients in septic shock, hemodynamically unstable or on high dose support
• Patients on mechanical ventilation for more than 1 week or less than 48 hours
• Patients not ready for start of weaning from mechanical ventilation
• Patients with neuromuscular disorders
• Pregnant females in the second and third trimester, patients with tense ascites or morbidly obese with body mass index more than 40 kg/m2

All patients will be intubated (for 2 - 7 days) and ready for weaning process. They will undergo diaphragmatic ultrasound on spontaneous breathing pattern on T-piece connected to 8L/min O2 with subsequent outcome either successful weaning or failed weaning

Individual patient data (IPD) that underlie the results reported in this article after deidentification (texts, tables, figures and appendices) will be available only for investigators whose purposed use of the data has been approved by an independent review committee identified for this purpose