Comparison of Flow Controlled Ventilation and Volume Controlled Ventilation
NCT Number: NCT06493162
Status: RECRUITING
Study Type: INTERVENTIONAL
Phases: NA
Conditions: Vocal Cord Disease|Vocal Cord Cyst
Interventions: PROCEDURE: Intubation|DEVICE: Flow Controlled Ventilation|DEVICE: Volume Controlled Ventilation
Sponsor: Kocaeli University
Sex: ALL
Age: ADULT, OLDER_ADULT
Enrollment: 68
Study Design: Allocation: RANDOMIZED|Intervention Model: PARALLEL|Masking: DOUBLE (PARTICIPANT, OUTCOMES_ASSESSOR)|Primary Purpose: SCREENING
Start Date: 2024-08-01
Completion Date: 2024-11-01
Locations: Kocaeli University, Kocaeli, 41350, Turkey

Summary:
Flow-Controlled Ventilation is designed to ventilate the patient with constant flows during both inspiration and expiration. During inspiration, the pressure rises linearly from a set positive end-expiratory pressure (PEEP) to a set positive inspiratory pressure (PIP), and then falls linearly from PIP to end-expiratory pressure (EEP) during expiration. There are no flow interruptions during the Flow-Controlled Ventilation cycle, and the rate of change of pressure and volume in the lungs is equal, allowing for higher tidal volumes at lower pressures. The user sets the inspiratory flow rate and the ratio of inspiratory to expiratory time, providing full control over the ventilation cycle. However, this results in two unusual features: During inspiration, the ventilator creates positive pressure to direct gas into the patient's lungs through the endotracheal tube (ETT). When the intratracheal pressure (airway pressure) reaches the set PIP value, the ventilator switches from inspiration to expiration. By reversing the flow, it utilizes the Bernoulli effect to create negative pressure, facilitating expiration. Despite the presence of negative pressure on the ventilator side, the pressure in the patient's airway remains positive at all times.

Volume-controlled ventilation is a mode that is volume-controlled, time-cycled, time-triggered, and pressure-limited. In volume-controlled ventilation, high pressures are sometimes necessary to reach the target tidal volume. This can lead to barotrauma, atelectrauma, and volutrauma in the lungs. Therefore, to avoid high pressures, low tidal volume ventilation is preferred.

For Microscopic Laryngeal Surgeries, patients are intubated with a small sized endotracheal tube which results with higher pressures. We think that flow controlled ventilation will improve the ventilation during the surgery with lower pressures.

Primary Outcome Measures: PIP, Peak inspiratory pressure, 10 minutes interval after the intubation during the surgery|RR, Respiratory rate, 10 minutes interval after the intubation during the surgery|TV, Tidal volume, 10 minutes interval after the intubation during the surgery|Compliance (Cdyn), Dynamic compliance (ventilator calculates: Cdyn = tidal volume/(PIP - PEEP), 10 minutes interval after the intubation during the surgery|Resistance, Resistance (ventilator calculates: dividing the \[peak pressure minus the plateau pressure\] by the flowrate in litres per second), 10 minutes interval after the intubation during the surgery
Secondary Outcome Measures: HR, Heart rate, 10 minutes interval after the intubation during the surgery|MP, Mean blood pressure, 10 minutes interval after the intubation during the surgery|SpO2, Oxygen saturation, 10 minutes interval after the intubation during the surgery