Anesthetized Healthy Patients (ASA 1 or 2) in the Supine Position, Excluding Head, Neck and Head SurgeriesNCT00225381

Gas Kinetics and Metabolism in Anesthesia During Non Steady State

An observational study of Anesthetized Healthy Patients (ASA 1 or 2) in the Supine Position, Excluding Head, Neck and Head Surgeries and Anesthetized Patient With Severe Systemic Disease (ASA 3 or 4), run by University of California, Irvine at 1 site in United States.

Withdrawn

Withdrawn. The study stopped before anyone enrolled.

Official record

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Trial summary

Who is it for?: Ages 18 years and olderHealthy volunteers can take part
Conditions the study is for: Anesthetized Healthy Patients (ASA 1 or 2) in the Supine Position, Excluding Head, Neck and Head Surgeries, Anesthetized Patient With Severe Systemic Disease (ASA 3 or 4)
What is being tested?: connection of measuring device to anesthesia circuit, drawing of blood sample through an arterial line, placed according to clinical criteria by primary anesthesia team and changing operating room bed position (head down and up position)
Type of treatment: Medical device, Surgery or procedure
How many people: 0 participants
Where: 1 siteUnited States
Study dates: Aug 2005to 13 Jan 2012
Phase: Observational
Are there results?: None posted in the registry

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

Ages 18 years and older
All sexes
Healthy volunteers accepted
Adult, Older adult

Study population: Adult patients in the supine position excluding surgeries around the head and neck area

Who may be able to join

All adult patients at UCIMC who are undergoing anesthesia and surgery are eligible for the studies
Patients must be American Society of Anesthesiologists (ASA) Class 1 or 2 (generally healthy patients). We plan on studying 100 patients, divided into 5 equally numbered groups. A power analysis of the sample size shows the need for minimum of 20 patients. High risk 3 subgroups (ASA 3), approximately 20 adult patients (included within the 100 planned patients), will be investigated for the (1) RQ correlation with arterial blood gas, (2) for the exercise study and (3) for the esophageal Doppler studies. These study groups include patients that are categorized as ASA 1, 2 or 3, (total of 60 patients) however; the total number of ASA 3 patients will not exceed 20. Subjects having surgeries around the head and neck, as well as surgeries that require the patient to lie face down will be excluded from the study
Gender and minority status will not be an exclusion factor for any potential study patient

Who cannot join

Cardiovascular:
Significant vascular disease, especially cardiac and cerebral vascular disease
Patients will be excluded if they have a history of having a myocardial infarction or cerebral vascular attack
Significant hypertension (> 170 systolic, > 90 diastolic) (except for the high risk subgroup mentioned before)
Pulmonary:
Significant asthma (mild persistent or greater according to the National Asthma Education and Prevention Program classification system) chronic obstructive pulmonary disease (COPD) (Stage II: Moderate COPD according to the Global Initiative for Chronic Obstructive Lung Disease classification

Show all 13Show fewer

Worsening airflow limitation, (FEV1 ≤30% ), and usually the progression of symptoms, with shortness of breath typically developing on exertion), bullous lung disease, or raised intra-cranial pressure (except for the high risk subgroup mentioned before)
Esophageal Doppler:
If localized pathology is present, including pharyngeal tumor or significant esophageal varices, then the esophageal probe will not be used.
Emergency cases:
Excluded from the study. Only elective patients will be enrolled.
Short surgeries:
Surgeries that are expected to last 45 minutes or less will be excluded.

Trial locations and contacts

1 site in 1 country.

United States1 site

University of California Irvine Medical Center
Orange, California, 92868

Other trials in United States

About this study

During clinical anesthesia, it is astonishing that CO2 monitoring consists mainly of end-tidal PCO2 to confirm endotracheal intubation and to estimate ventilation, and O2 monitoring consists of a single PO2 measurement to detect a hypoxic gas mixture. Better understanding of how O2 and CO2 kinetics monitoring can define systems pathophysiology will greatly enhance safety in anesthesia by detecting critical events such as abrupt decrease in cardiac output (Q.T) by vena-caval compression during abdominal surgery, occurrence of CO2 pulmonary embolism during laparoscopy, rising tissue O2 consumption (V.O2) during light anesthesia, and onset of anaerobic metabolism (V.CO2 is disproportionately higher than V.O2).

Read the detailed description

In the previous grant period, discoveries of CO2 kinetics during non-steady state revealed significant gaps in understanding of O2 kinetics. To this end, a 5-compartment lung model of gas kinetics in the body during non-steady state has been developed, that incorporates complex interactions between O2 and CO2 in the lung, blood, and tissues. This computer model was used to formulate the following hypotheses, and will elucidate mechanisms underlying the subsequent measured data in anesthetized patients.

The investigators have already developed two innovative devices that are essential for the V.O2 measurement: A fast response temperature and humidity sensor, and a mixing device (a bymixer) for the measurement of mixed gas fraction, especially designed for anesthesia systems. The investigators have also designed a sophisticated bench system for the validation of both devices, which showed the high accuracy and performance of our measurements.

Hypotheses that will be tested in our overall research theme include:

That pulmonary O2 uptake (V.O2) in anesthetized patients is much lower than the value quoted in the literature.
That inhalation anesthesia influences V.O2 differently than total intravenous anesthesia (TIVA).
That an acute decrease in cardiac output (Q.T) (by patient position change) will transiently decrease V.O2 but the decrease in CO2 elimination (V.CO2) is sustained because tissue CO2 stores are a hundred fold greater than O2 (please see previously approved IRB protocol, HS# 2000-1325).
That positive end-expiratory pressure (PEEP) decreases V.O2 and V.CO2 due to decreases in Q.T and alveolar ventilation (V.A), and appearance of high ventilation-to-perfusion (V.A/Q.) units (please see previously approved IRB protocol, HS# 2000-1325).
That Trendelenburg (head down) position increases V.O2 and V.CO2 due to increase in Q.T.
That V.O2 can help to determine the necessity of blood transfusion.
That the continuous measurement of the respiratory quotient (RQ=V.CO2/V.O2) can detect transition to anaerobic metabolism.
That the continuous measurement of the respiratory RQ can be a good alternative to arterial blood gas sampling.
That the continuous measurement of the respiratory RQ can determine the necessity of nutritional support during long operations.

In this protocol, the investigators will study the clinical implications of these measurements, believing that they are the missing links in anesthesia monitoring. Elucidating the mechanisms underlying this acute pathophysiology will advance the understanding of O2 and CO2 kinetics during non-steady state, and allow the non-invasive diagnosis of critical events during clinical anesthesia conferring increased safety, especially for the majority of healthy patients who receive only non-invasive monitoring.

A separate section of the study, which compliments the metabolic gas exchange study with the bymixer flow system is the examination of respiratory gas with a portable mass-spectrometer to detect volatile organic compounds during anaerobic metabolism. The experimental anaerobic model is adult patients undergoing a surgery that requires tourniquet. Anaerobic metabolism will be detected by acid base balance blood test, the bymixer flow measurement and the mass spectrometer. Anesthesia will be maintained by total intravenous anesthesia (TIVA) and each patient will have an arterial line. No other intervention would be taken. It is an observational type study.

Conditions: Anesthetized Healthy Patients (ASA 1 or 2) in the Supine Position, Excluding Head, Neck and Head Surgeries, Anesthetized Patient With Severe Systemic Disease (ASA 3 or 4)
Being tested: connection of measuring device to anesthesia circuit, drawing of blood sample through an arterial line, placed according to clinical criteria by primary anesthesia team, changing operating room bed position (head down and up position), adding PEEP during anesthesia, placement of esophageal Doppler for cardiac output measurements
Keywords: Oxygen consumption, CO2 production, Indirect calorimetry, Non steady state, Anesthesia monitoring, Critical events during anesthesia, Acid base balance, Metabolism during anesthesia

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

connection of measuring device to anesthesia circuitDevice
same as name
drawing of blood sample through an arterial line, placed according to clinical criteria by primary anesthesia teamProcedure or surgery
same
changing operating room bed position (head down and up position)Procedure or surgery
same
adding PEEP during anesthesiaProcedure or surgery
same
placement of esophageal Doppler for cardiac output measurementsProcedure or surgery
same
Humidity sensorDevice
Small conventional anesthesia T piece including tiny 2 thermometer inside
A mixing chamber (bymixer)Device
2 mixing chambers (bymixers) composed of 2 arms where one arm serves as a mixing (passive) arm for the measurement of mixed gas fraction. The bymixer is made of conventional anesthesia supplies and does not influence dead space nor circuit resistance.
Pneumotachometer cuvetteDevice
The pneumotachometer cuvette is used by many anesthesia monitors to measure gas flow.
Mass spectrometer sampling portDevice
Also called V&F Instruments, Airsense (www.vandf.com)
Designed for the anesthesia tubing and connected at the airway opening. it has small volume (3 mL) and do not influence circuit resistance.

Study groups in NCT00225381
Study group	Role	What they receive
metabolic gas exchange and cardiac output		Not described Receives: Device: connection of measuring device to anesthesia circuit; Procedure: placement of esophageal Doppler for cardiac output measurements; Device: Humidity sensor; Device: A mixing chamber (bymixer); Device: Pneumotachometer cuvette
mass spectrometer and anaerobic metabolism		Not described Receives: Device: connection of measuring device to anesthesia circuit; Procedure: drawing of blood sample through an arterial line, placed according to clinical criteria by primary anesthesia team; Device: Humidity sensor; Device: A mixing chamber (bymixer); Device: Pneumotachometer cuvette; Device: Mass spectrometer sampling port
metaboic gas exchange and type of anesthesia induction		Not described Receives: Device: connection of measuring device to anesthesia circuit; Device: Humidity sensor; Device: A mixing chamber (bymixer); Device: Pneumotachometer cuvette
metabolic gas exchange and PEEP		Not described Receives: Device: connection of measuring device to anesthesia circuit; Procedure: adding PEEP during anesthesia; Device: Humidity sensor; Device: A mixing chamber (bymixer); Device: Pneumotachometer cuvette
metabolic gas exchange and trendelenburg position		Not described Receives: Device: connection of measuring device to anesthesia circuit; Procedure: changing operating room bed position (head down and up position); Device: Humidity sensor; Device: A mixing chamber (bymixer); Device: Pneumotachometer cuvette
Patients requiring tourniquet during surgery		Patients undergoing orthopaedic surgeries requiring tourniquet intervention. Oxygen consumption and CO2 production were measured before, during and after tourniquet release.
Patients prone to metabolic acidosis		Oxygen consumption and CO2 measurements taken during long surgeries prone to metabolic acidosis.

What is being measured

The primary outcome is the main question the study is designed to answer.

Correlation between VO2 to type of anesthesia maintenance
Measured: 45 minutes
Correlation between acid base balance and indirect calorimetry
Measured: 2 hours
Detection of volatile organic compound during anaerobic metabolism
Measured: 3 hours
Influence of anesthesia induction on metabolic gas exchange
Measured: 45 minutes

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

Aug 200513 Jan 2012

First posted23 Sep 2005 (estimated)
Study startAug 2005
Primary completion13 Jan 2012
Study completion13 Jan 2012

Why it stopped: Non Applicable clinical trial

Resources

Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
Publications (11)Papers the sponsor has linked to this study.
Other trials for Anesthetized Healthy Patients (ASA 1 or 2) in the Supine Position, Excluding Head, Neck and Head SurgeriesStudies of the same condition, open and under way.
More trials run by University of California, IrvineThe sponsor's other registered studies.
What the trial phases meanHow a treatment moves from first tests in people to approval.

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design

Study type: Observational
Observational model: Case only
Time perspective: Other
Enrolment: 0 participants (actual)

IDs, dates and publications

ClinicalTrials.gov ID: NCT00225381
Sponsor's protocol ID: R01 HL 42637 [HS# 2005-4256]
Other IDs: (UCI IRB ID)2005-4256, R01HL042637
Status last verified: Mar 2021
First submitted: 21 Sep 2005
Last updated: 23 Mar 2021
Results posted: No
Data monitoring committee: No

Publications

Rosenbaum A, Kirby C, Breen PH. Measurement of oxygen uptake and carbon dioxide elimination using the bymixer: validation in a metabolic lung simulator. Anesthesiology. 2004 Jun;100(6):1427-37. doi: 10.1097/00000542-200406000-00015.
PubMed 15166562
Rosenbaum A, Breen PH. Novel, adjustable, clinical bymixer measures mixed expired gas concentrations in anesthesia circle circuit. Anesth Analg. 2003 Nov;97(5):1414-1420. doi: 10.1213/01.ANE.0000083420.15268.3A.
PubMed 14570659
Breen PH, Isserles SA, Taitelman UZ. Non-steady state monitoring by respiratory gas exchange. J Clin Monit Comput. 2000;16(5-6):351-60. doi: 10.1023/a:1011447500984.
PubMed 12580218
Breen PH. Importance of temperature and humidity in the measurement of pulmonary oxygen uptake per breath during anesthesia. Ann Biomed Eng. 2000 Sep;28(9):1159-64. doi: 10.1114/1.1312184.
PubMed 11132200
Breen PH, Serina ER. Bymixer provides on-line calibration of measurement of CO2 volume exhaled per breath. Ann Biomed Eng. 1997 Jan-Feb;25(1):164-71. doi: 10.1007/BF02738547.
PubMed 9124730
Breen PH, Serina ER, Barker SJ. Measurement of pulmonary CO2 elimination must exclude inspired CO2 measured at the capnometer sampling site. J Clin Monit. 1996 May;12(3):231-6. doi: 10.1007/BF00857644.
PubMed 8823647
Breen PH, Mazumdar B, Skinner SC. Capnometer transport delay: measurement and clinical implications. Anesth Analg. 1994 Mar;78(3):584-6. doi: 10.1213/00000539-199403000-00027.
PubMed 8109779
Breen PH, Isserles SA, Harrison BA, Roizen MF. Simple computer measurement of pulmonary VCO2 per breath. J Appl Physiol (1985). 1992 May;72(5):2029-35. doi: 10.1152/jappl.1992.72.5.2029.
PubMed 1601815
Isserles SA, Breen PH. Can changes in end-tidal PCO2 measure changes in cardiac output? Anesth Analg. 1991 Dec;73(6):808-14. doi: 10.1213/00000539-199112000-00023.
PubMed 1952183
Rosenbaum A, Breen PH. Importance and interpretation of fast-response airway hygrometry during ventilation of anesthetized patients. J Clin Monit Comput. 2007 Jun;21(3):137-46. doi: 10.1007/s10877-006-9065-5. Epub 2007 Mar 16.
PubMed 17364215
Rosenbaum A, Kirby C, Breen PH. New metabolic lung simulator: development, description, and validation. J Clin Monit Comput. 2007 Apr;21(2):71-82. doi: 10.1007/s10877-006-9058-4. Epub 2007 Mar 1.
PubMed 17333487

Study at a glance

From the registry record, last updated by the sponsor on 23 Mar 2021. Recruitment status is as the sponsor reported it: confirm with the study team.

Official title: Gas Kinetics and Metabolism in Anesthesia During Non Steady State
ClinicalTrials.gov ID: NCT00225381
Acronym / sponsor ID: R01 HL 42637 [HS# 2005-4256]
Conditions: Anesthetized Healthy Patients (ASA 1 or 2) in the Supine Position, Excluding Head, Neck and Head Surgeries, Anesthetized Patient With Severe Systemic Disease (ASA 3 or 4)
Keywords: Oxygen consumption, CO2 production, Indirect calorimetry, Non steady state, Anesthesia monitoring, Critical events during anesthesia, Acid base balance, Metabolism during anesthesia
Study type: Observational
Recruitment status: WithdrawnReason stopped: Non Applicable clinical trial
Enrolment: 0 participants (actual)
Lead sponsor: University of California, IrvineUniversity, hospital or other
Study start: Aug 2005
Primary completion: 13 Jan 2012 (actual)
Study completion: 13 Jan 2012 (actual)
First posted: 23 Sep 2005 (estimated)
Results: Not posted in the source record

Clinical summary

The research question as the sponsor registered it. This describes what the study plans to test, not what it found.

Detailed description

Hypotheses that will be tested in our overall research theme include:

That pulmonary O2 uptake (V.O2) in anesthetized patients is much lower than the value quoted in the literature.
That inhalation anesthesia influences V.O2 differently than total intravenous anesthesia (TIVA).
That an acute decrease in cardiac output (Q.T) (by patient position change) will transiently decrease V.O2 but the decrease in CO2 elimination (V.CO2) is sustained because tissue CO2 stores are a hundred fold greater than O2 (please see previously approved IRB protocol, HS# 2000-1325).
That positive end-expiratory pressure (PEEP) decreases V.O2 and V.CO2 due to decreases in Q.T and alveolar ventilation (V.A), and appearance of high ventilation-to-perfusion (V.A/Q.) units (please see previously approved IRB protocol, HS# 2000-1325).
That Trendelenburg (head down) position increases V.O2 and V.CO2 due to increase in Q.T.
That V.O2 can help to determine the necessity of blood transfusion.
That the continuous measurement of the respiratory quotient (RQ=V.CO2/V.O2) can detect transition to anaerobic metabolism.
That the continuous measurement of the respiratory RQ can be a good alternative to arterial blood gas sampling.
That the continuous measurement of the respiratory RQ can determine the necessity of nutritional support during long operations.

Study design

Observational model: Case only
Time perspective: Other
Number of arms: 7

Arm	Type	Receives
metabolic gas exchange and cardiac output	–	Device: connection of measuring device to anesthesia circuit, Procedure: placement of esophageal Doppler for cardiac output measurements, Device: Humidity sensor, Device: A mixing chamber (bymixer), Device: Pneumotachometer cuvette
mass spectrometer and anaerobic metabolism	–	Device: connection of measuring device to anesthesia circuit, Procedure: drawing of blood sample through an arterial line, placed according to clinical criteria by primary anesthesia team, Device: Humidity sensor, Device: A mixing chamber (bymixer), Device: Pneumotachometer cuvette, Device: Mass spectrometer sampling port
metaboic gas exchange and type of anesthesia induction	–	Device: connection of measuring device to anesthesia circuit, Device: Humidity sensor, Device: A mixing chamber (bymixer), Device: Pneumotachometer cuvette
metabolic gas exchange and PEEP	–	Device: connection of measuring device to anesthesia circuit, Procedure: adding PEEP during anesthesia, Device: Humidity sensor, Device: A mixing chamber (bymixer), Device: Pneumotachometer cuvette
metabolic gas exchange and trendelenburg position	–	Device: connection of measuring device to anesthesia circuit, Procedure: changing operating room bed position (head down and up position), Device: Humidity sensor, Device: A mixing chamber (bymixer), Device: Pneumotachometer cuvette
Patients requiring tourniquet during surgery	–	–Patients undergoing orthopaedic surgeries requiring tourniquet intervention. Oxygen consumption and CO2 production were measured before, during and after tourniquet release.
Patients prone to metabolic acidosis	–	–Oxygen consumption and CO2 measurements taken during long surgeries prone to metabolic acidosis.

Who may qualify

Ages: 18 years and older
Sex: All
Healthy volunteers: Accepted
Age groups: Adult, Older adult
Study population: Adult patients in the supine position excluding surgeries around the head and neck area

Key inclusion criteria (3 listed)

All adult patients at UCIMC who are undergoing anesthesia and surgery are eligible for the studies
Patients must be American Society of Anesthesiologists (ASA) Class 1 or 2 (generally healthy patients). We plan on studying 100 patients, divided into 5 equally numbered groups. A power analysis of the sample size shows the need for minimum of 20 patients. High risk 3 subgroups (ASA 3), approximately 20 adult patients (included within the 100 planned patients), will be investigated for the (1) RQ correlation with arterial blood gas, (2) for the exercise study and (3) for the esophageal Doppler studies. These study groups include patients that are categorized as ASA 1, 2 or 3, (total of 60 patients) however; the total number of ASA 3 patients will not exceed 20. Subjects having surgeries around the head and neck, as well as surgeries that require the patient to lie face down will be excluded from the study
Gender and minority status will not be an exclusion factor for any potential study patient

Key exclusion criteria (13 listed)

Significant vascular disease, especially cardiac and cerebral vascular disease
Patients will be excluded if they have a history of having a myocardial infarction or cerebral vascular attack
Significant hypertension (> 170 systolic, > 90 diastolic) (except for the high risk subgroup mentioned before)
Significant asthma (mild persistent or greater according to the National Asthma Education and Prevention Program classification system) chronic obstructive pulmonary disease (COPD) (Stage II: Moderate COPD according to the Global Initiative for Chronic Obstructive Lung Disease classification
Worsening airflow limitation, (FEV1 ≤30% ), and usually the progression of symptoms, with shortness of breath typically developing on exertion), bullous lung disease, or raised intra-cranial pressure (except for the high risk subgroup mentioned before)

Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.

Interventions

Intervention	Type	Arms
connection of measuring device to anesthesia circuitsame as name	Device	mass spectrometer and anaerobic metabolism, metaboic gas exchange and type of anesthesia induction, metabolic gas exchange and PEEP, metabolic gas exchange and cardiac output, metabolic gas exchange and trendelenburg position
drawing of blood sample through an arterial line, placed according to clinical criteria by primary anesthesia teamsame	Procedure or surgery	mass spectrometer and anaerobic metabolism
changing operating room bed position (head down and up position)same	Procedure or surgery	metabolic gas exchange and trendelenburg position
adding PEEP during anesthesiasame	Procedure or surgery	metabolic gas exchange and PEEP
placement of esophageal Doppler for cardiac output measurementssame	Procedure or surgery	metabolic gas exchange and cardiac output
Humidity sensorSmall conventional anesthesia T piece including tiny 2 thermometer inside	Device	mass spectrometer and anaerobic metabolism, metaboic gas exchange and type of anesthesia induction, metabolic gas exchange and PEEP, metabolic gas exchange and cardiac output, metabolic gas exchange and trendelenburg position
A mixing chamber (bymixer)2 mixing chambers (bymixers) composed of 2 arms where one arm serves as a mixing (passive) arm for the measurement of mixed gas fraction. The bymixer is made of conventional anesthesia supplies and does not influence dead space nor circuit resistance.	Device	mass spectrometer and anaerobic metabolism, metaboic gas exchange and type of anesthesia induction, metabolic gas exchange and PEEP, metabolic gas exchange and cardiac output, metabolic gas exchange and trendelenburg position
Pneumotachometer cuvetteThe pneumotachometer cuvette is used by many anesthesia monitors to measure gas flow.	Device	mass spectrometer and anaerobic metabolism, metaboic gas exchange and type of anesthesia induction, metabolic gas exchange and PEEP, metabolic gas exchange and cardiac output, metabolic gas exchange and trendelenburg position
Mass spectrometer sampling portAlso: V&F Instruments, Airsense (www.vandf.com)Designed for the anesthesia tubing and connected at the airway opening. it has small volume (3 mL) and do not influence circuit resistance.	Device	mass spectrometer and anaerobic metabolism

Primary outcome

Correlation between VO2 to type of anesthesia maintenance
Time frame: 45 minutes
Correlation between acid base balance and indirect calorimetry
Time frame: 2 hours
Detection of volatile organic compound during anaerobic metabolism
Time frame: 3 hours
Influence of anesthesia induction on metabolic gas exchange
Time frame: 45 minutes

Results and safety

The study was withdrawn before enrolling participants, so there are no results.

Research links

Official record on ClinicalTrials.govLast updated by the sponsor 23 Mar 2021.
Background: PubMed 15166562Rosenbaum A, Kirby C, Breen PH. Measurement of oxygen uptake and carbon dioxide elimination using the bymixer: validation in a metabolic lung simulator. Anesthesiology. 2004 Jun;100(6):1427-37. doi: 10.1097/00000542-200406000-00015.
Background: PubMed 14570659Rosenbaum A, Breen PH. Novel, adjustable, clinical bymixer measures mixed expired gas concentrations in anesthesia circle circuit. Anesth Analg. 2003 Nov;97(5):1414-1420. doi: 10.1213/01.ANE.0000083420.15268.3A.
Background: PubMed 12580218Breen PH, Isserles SA, Taitelman UZ. Non-steady state monitoring by respiratory gas exchange. J Clin Monit Comput. 2000;16(5-6):351-60. doi: 10.1023/a:1011447500984.
Background: PubMed 11132200Breen PH. Importance of temperature and humidity in the measurement of pulmonary oxygen uptake per breath during anesthesia. Ann Biomed Eng. 2000 Sep;28(9):1159-64. doi: 10.1114/1.1312184.
Background: PubMed 9124730Breen PH, Serina ER. Bymixer provides on-line calibration of measurement of CO2 volume exhaled per breath. Ann Biomed Eng. 1997 Jan-Feb;25(1):164-71. doi: 10.1007/BF02738547.
Background: PubMed 8823647Breen PH, Serina ER, Barker SJ. Measurement of pulmonary CO2 elimination must exclude inspired CO2 measured at the capnometer sampling site. J Clin Monit. 1996 May;12(3):231-6. doi: 10.1007/BF00857644.
Background: PubMed 8109779Breen PH, Mazumdar B, Skinner SC. Capnometer transport delay: measurement and clinical implications. Anesth Analg. 1994 Mar;78(3):584-6. doi: 10.1213/00000539-199403000-00027.
Background: PubMed 1601815Breen PH, Isserles SA, Harrison BA, Roizen MF. Simple computer measurement of pulmonary VCO2 per breath. J Appl Physiol (1985). 1992 May;72(5):2029-35. doi: 10.1152/jappl.1992.72.5.2029.
Background: PubMed 1952183Isserles SA, Breen PH. Can changes in end-tidal PCO2 measure changes in cardiac output? Anesth Analg. 1991 Dec;73(6):808-14. doi: 10.1213/00000539-199112000-00023.
Results publication: PubMed 17364215Rosenbaum A, Breen PH. Importance and interpretation of fast-response airway hygrometry during ventilation of anesthetized patients. J Clin Monit Comput. 2007 Jun;21(3):137-46. doi: 10.1007/s10877-006-9065-5. Epub 2007 Mar 16.
Results publication: PubMed 17333487Rosenbaum A, Kirby C, Breen PH. New metabolic lung simulator: development, description, and validation. J Clin Monit Comput. 2007 Apr;21(2):71-82. doi: 10.1007/s10877-006-9058-4. Epub 2007 Mar 1.
Related InfoLink provided by the sponsor.

Referral and contact

AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.

Peter H Breen, MD, FRCPC principal investigator

UCI Medical Center

Abraham Rosenbaum, MD study director

UCI Medical Center

1 site in 1 country: see every site and its status.

Questions about this trial

What is this clinical trial studying?

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 3 inclusion and 13 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: withdrawn, as of the sponsor's last update on 23 Mar 2021. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

Are results available for this study?

The study was withdrawn before enrolling participants, so there are no results.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Correlation between VO2 to type of anesthesia maintenance (time frame: 45 minutes). The study lists 4 primary outcomes in all. It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT00225381, which also lists 11 linked publications.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 23 Mar 2021.