AVAS: Automated Control of Mechanical Ventilation During General Anaesthesia
Study Details
Study Description
Brief Summary
Prospective, bicentric observational study to assess a novel system for automated control of mechanical ventilation (Smart Vent Control, SVC) during general anesthesia.
| Condition or Disease | Intervention/Treatment | Phase |
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Detailed Description
The "Automated control of mechanical ventilation during general anesthesia study (AVAS study) is an international investigator-initiated bicentric observational study investigating the application of Smart Vent Control (SVC) during general anesthesia. The main objective of this study is to describe the application of SVC and to assess its safety and efficacy.
Study Design
Outcome Measures
Primary Outcome Measures
- Frequency of adverse events. [During artificial ventilation with SVC (up to 8 hours).]
Severe hypoventilation defined as minute volume lower than 40 ml/kg predicted body weight for longer than 5 minutes Apnea for longer than 90 seconds Hyperventilation defined as PetCO2 lower than 5 mm Hg of the lower target setting for SVC for longer than 5 minutes Hypoventilation defined as PetCO2 higher than 5 mm Hg of the upper target setting for the SVC for longer than 5 minutes Respiratory rate > 35 breaths per minute for longer than 5 minutes Any override or stop of the automated controlled ventilation settings by the anesthesiologist in charge if the settings are clinically not acceptable. Reasons for overriding or stopping the system will be noted.
Secondary Outcome Measures
- Frequency of normoventilated, hypoventilated and hyperventilated patients. [During artificial ventilation with SVC (up to 8 hours).]
The responsible anesthesiologist defines a target range for the arterial partial pressure of carbon dioxide (PaCO2_target) before the induction of the general anesthesia and sets up the corresponding endtidal CO2-range in the automated ventilation system. 15 minutes after the begin of the surgical procedure an arterial blood gas analysis will be performed and the PaCO2 will be measured. Then patients will be classified as follows: hypoventilated patient: PaCO2 > (PaCO2_target+5) hyperventilated patient: PaCO2 < (PaCO2_target-5) normoventilated patient: (PaCO2_target-5) ≤ PaCO2 ≤ PaCO2_target+5
- Time period between switch from controlled ventilation to augmented ventilation and achievement of stable assisted ventilation of the patient. [During artificial ventilation with SVC (up to 8 hours).]
- Proportion of time within the target zones for tidal volume and PetCO2 as individually set up for each patient by the user. [During artificial ventilation with SVC (up to 8 hours).]
- Frequency of alarms. [During artificial ventilation with SVC (up to 8 hours).]
- Frequency distribution of tidal volume (ml/kg predicted body weight). [During artificial ventilation with SVC (up to 8 hours).]
- Frequency distribution of inspiratory pressure (mbar). [During artificial ventilation with SVC (up to 8 hours).]
- Frequency distribution of inspiration time (s). [During artificial ventilation with SVC (up to 8 hours).]
- Frequency distribution of expiration time (s). [During artificial ventilation with SVC (up to 8 hours).]
- Frequency distribution of PetCO2 (mmHg). [During artificial ventilation with SVC (up to 8 hours).]
- Number of re-intubations. [During artificial ventilation with SVC (up to 8 hours).]
Eligibility Criteria
Criteria
Inclusion Criteria:
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Planned elective surgery of the upper limb, lower limb or peripheral vascular surgery in general anesthesia
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Patient is classified as American Society of Anesthesiologists physical status (ASA) I, II or III
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Age ≥ 18 years
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Written consent of the patient for study participation
Exclusion Criteria:
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Mild, moderate or severe acute respiratory distress syndrome (ARDS)[10]
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Known chronic obstructive pulmonary disease Gold stage III or higher
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Two or more of the following organ failures
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Mild, moderate or severe ARDS
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Hemodynamic instability: systolic blood pressure < 90 mm Hg, mean arterial pressure < 70 mm Hg or administration of any vasoactive drugs.
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Acute renal failure: oliguria (urine output < 0.5 ml/kg/h for at least 2 hours despite of adequate management or creatinine increase > 0.5 mg/dl
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Cerebral failure: loose of consciousness or encephalopathy
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Patient is pregnant.
Contacts and Locations
Locations
| Site | City | State | Country | Postal Code | |
|---|---|---|---|---|---|
| 1 | University Hospital St. Pölten, Department of Anesthesiology and Intensive Care Medicine | St. Pölten | Austria | A-3100 | |
| 2 | University Medical Center Schleswig-Holstein, Campus Kiel, Department of Anesthesiology and Intensive Care Medicine | Kiel | Germany | 24105 |
Sponsors and Collaborators
- University Hospital Schleswig-Holstein
- Drägerwerk AG & Co. KGaA
Investigators
- Principal Investigator: Norbert Weiler, M.D., University Medical Center Schleswig-Holstein, Campus Kiel, Germany, Department of Anesthesiology and Intensive Care Medicine
- Principal Investigator: Christoph Hörmann, M.D., University Hospital St. Pölten, Austria, Department of Anesthesiology and Intensive Care Medicine
Study Documents (Full-Text)
None provided.More Information
Publications
- AVAS