Transnasal Humidified Rapid-Insufflation Ventilatory Exchange (THRIVE) Apnoeic Ventilation During Operative Hysteroscopic Procedures Under General Anesthesia: an Observational Study.
Trial Snapshot
- Phase
- Not Applicable
- Status
- Completed
- Enrollment
- 30
- Locations
- 1
- Primary Endpoint
- change of tCO2 during THRIVE ventilation.
Study Overview
Brief Summary
Transnasal Humidified Rapid-Insufflation Ventilatory Exchange (THRIVE) allows to extend the apnoeic window in patients undergoing general anesthesia by delivering 100% of heated and humidified oxygen at 70L/min in order to maintain viable gas exchange during an extended period of cessation of spontaneous ventilation.
This technique has been successfully applied in several clinical settings (induction of general anesthesia, laryngoscopy in predicted difficult airway management, and as unique airway management technique for procedural sedation or general anesthesia for brief surgical procedures).
Operative hysteroscopy is a brief surgical procedure usually performed under general anesthesia with intravenous agents (propofol plus fentanyl) and positive pressure ventilation through facial or laryngeal mask.
The aim of this study is to investigate the effects of THRIVE apnoeic ventilation during hysteroscopy under general anesthesia. Our primary outcome is to describe the trend of SpO2 and tcCO2 during the procedures.
Secondary outcomes include description of arrhythmias requiring medical treatment, hemodynamic instability, unmanageable copious secretions, airway obstruction or inability to maintain airway patency, witnessed aspiration, airway related complications, number of airway manipulations, adverse events, assessment of postoperative dyspnoea and comfort, patient satisfaction.
Women (> 18 years old and < 70 years old), ASA physical status I and II presenting for elective operative hysteroscopies will be included.
A number of 30 patients was planned to target the primary outcome.
Detailed Description
Background Transnasal Humidified Rapid-Insufflation Ventilatory Exchange (THRIVE), term coined by Patel and Nouraei, refers to a technique that allows to extend the apnoeic window in patients undergoing general anesthesia by delivering 100% of heated and humidified oxygen at 70L/min using the Optiflow THRIVE-TM system (Fisher and Paykel Healthcare Ltd, Auckland, New Zealand), in order to maintain viable gas exchange during an extended period of cessation of muscular activity.
Apnoeic oxygenation is a physiological phenomenon in which oxygen flow into the lungs is driven by a negative pressure gradient generated by the difference between the alveolar rates of oxygen absorption and carbon dioxide excretion.
Potentially rapid and dangerous rise in carbon dioxide concentration is prevented by the underlying mechanisms occurring during high-flow nasal oxygenation under apnoeic conditions.
As proposed by Slutsky and more recently by Hermez, cardiogenic oscillations (changes in airway gas flow and pressure synchronous with the cardiac cycle) and their interactions with supraglottic turbulence generated by high-flow nasal oxygenation might be the underlying mechanisms of THRIVE and of the enhanced clearance of carbon dioxide.
Many clinically relevant benefits have been associated with nasal high flow. It provides a constant FiO2 by delivering the gas at flow rates that exceed the patient's peak inspiratory flow rate. It is effective in providing a flow-dependent effect of continuous positive airway pressure of about 1 cmH20 for every 10 L/min increase in gas flow within a range of 30-50 L/min, up to 11.9 cm H20 at a maximum flow of 100 L/min. Moreover, it reduces respiratory rate, it clears in a dose-dependent manner dead space of the upper airways and possibly even below the soft palate, leading to a reduction in rebreathing of expired air, with the potential to increase the alveolar volume and to improve alveolar ventilation and gas exchange. It is likely that, especially in patients with mild to moderate respiratory failure, enhanced comfort from heated humidification and flushing of dead space, lessen the work of breathing, thus improving thoraco-abdominal synchrony. By contrast, in spontaneously breathing patients, as a consequence of the large amount of air inflated into the stomach, higher number of reflux events could be detected increasing the risks of aspiration.
Study Design
- Study Type
- Observational
- Observational Model
- Case Only
- Time Perspective
- Prospective
Eligibility Criteria
- Ages
- 18 Years to 70 Years (Adult, Older Adult)
- Sex
- Female
- Accepts Healthy Volunteers
- No
Inclusion Criteria
- •ASA I-II.
Exclusion Criteria
- •BMI > 30,
- •pregnancy,
- •cardiac arrhythmia,
- •high risk of aspiration,
- •neuromuscular disease,
- •patient refusal.
Outcomes
Primary Outcomes
change of tCO2 during THRIVE ventilation.
Time Frame: pre-anesthesia; up to 1 hour.
CO2 values (reported as mmHg) measured by Radiometer monitor.
change of SpO2 during THRIVE ventilation.
Time Frame: pre-anesthesia; up to 1 hour.
SpO2 values (reported as "%") measured by oxymeter.
Secondary Outcomes
- Airway related complications.(2 hours after the end of anesthesia.)
- Postoperative complications - 1(2 hours after the end of anesthesia.)
- Postoperative complications - 2(2 hours after the end of anesthesia.)
- Postoperative complications - 3(2 hours after the end of anesthesia.)