Sleep Quality in Mechanically Ventilated Patients

The Influence of Mode and Patient-ventilator Interaction on Sleep Quality in the ICU

Patients requiring mechanical ventilation in the ICU will undergo three consecutive nights of polysomnography to record sleep patterns while receiving three modes of mechanical ventilation; Proportional assist ventilation (PAV), Pressure support ventilation (PSV), Assist control ventilation (ACV), applied in random order. The purpose is to determine the effect of mode of mechanical ventilation on patient-ventilator asynchrony and sleep quality.

Inclusion Criteria:

• Age 18-75
• received mechanical ventilation >72 hours
• glasgow coma scale >10
• acute physiology score <13
• ready for partial ventilatory support: intact respiratory drive, PaO2/FiO2 ratio >200 on positive end expiratory pressure (PEEP) less than or equal to 5 cmH2O, and PH of 7.35 to 7.45
• sedation: analgesia at dose not higher than 0.01 mg/kg/hr morphine equivalent x 48 hours, sedation at dose not higher than 0.01 mg/kg/hr lorazepam equivalent x 72 hours.
• anticipate ongoing need for partial ventilatory support for the following 72 hours

Exclusion Criteria:

• Successful completion of spontaneous breathing trial
• Neurological injury, encephalopathy or abnormal EEG
• History of central sleep apnea
• General anaesthesia within 72 hours from study entry
• Requiring haloperidol >10 mg/24 hours
• hemodynamically unstable
• sepsis