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Trial record 9 of 711 for:    CARBON DIOXIDE AND arterial

A Comparison of the Detection of Hypoventilation During Deep Sedation Utilizing Nasal End Title CO@ Versus Transcutaneous CO2 Measurement Techniques

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT00954733
Recruitment Status : Completed
First Posted : August 7, 2009
Results First Posted : July 24, 2014
Last Update Posted : July 24, 2014
Information provided by (Responsible Party):
Gildasio De Oliveira, Northwestern University

Tracking Information
First Submitted Date  ICMJE August 5, 2009
First Posted Date  ICMJE August 7, 2009
Results First Submitted Date  ICMJE June 25, 2014
Results First Posted Date  ICMJE July 24, 2014
Last Update Posted Date July 24, 2014
Study Start Date  ICMJE June 2009
Actual Primary Completion Date August 2009   (Final data collection date for primary outcome measure)
Current Primary Outcome Measures  ICMJE
 (submitted: June 25, 2014)
TcCo2 vs PACo2 Difference [ Time Frame: 1 hour ]
Evaluate the correlation between PaCO2- TcCO2 in detecting hypoventilation for patients undergoing deep sedation Absolute mean difference between TcCo2 and the PA Co2
Original Primary Outcome Measures  ICMJE
 (submitted: August 6, 2009)
Evaluate the correlation between PaCO2 - ETCO2 versus PaCO2- TcCO2 in detecting hypoventilation for patients undergoing deep sedation [ Time Frame: 1 hour ]
Change History
Current Secondary Outcome Measures  ICMJE Not Provided
Original Secondary Outcome Measures  ICMJE
 (submitted: August 6, 2009)
Subjects with SaO2 less than 90% on 3L oxygen by nasal cannula. Subjects requiring airway supporting measures; jaw support, oral / nasal airway. Subjects converted to general anesthesia due to inadequacy of deep sedation [ Time Frame: 1 hour ]
Current Other Pre-specified Outcome Measures Not Provided
Original Other Pre-specified Outcome Measures Not Provided
Descriptive Information
Brief Title  ICMJE A Comparison of the Detection of Hypoventilation During Deep Sedation Utilizing Nasal End Title CO@ Versus Transcutaneous CO2 Measurement Techniques
Official Title  ICMJE A Comparison of the Detection of Hypoventilation During Deep Sedation Utilizing Nasal End Title CO@ Versus Transcutaneous CO2 Measurement Techniques
Brief Summary

The estimation of the partial pressure of carbon dioxide (PCO2) in the arterial blood is used to judge the adequacy of ventilation during spontaneous and controlled ventilation. Although the gold standard for monitoring PCO2 remains arterial blood gas sampling, this requires an invasive procedure and provides only an intermittent estimate of what is frequently a continuously changing value. The solution to this problem has been the development and validation of accurate noninvasive monitoring techniques which provide a continuous intraoperative estimate of PCO2.The most commonly used noninvasive technique to monitor PCO2 is measurement of the end tidal CO2 (PECO2) . However, sampling errors and patient -related issues such as ventilation-perfusion mismatch, patient positioning or decreases in pulmonary blood flow may influence the accuracy of PECO2 monitoring (1-3). Nasal capnography has been proved to be an accurate monitor during the post-operative period (4) but its ability to accurately detect hypoventilation associated with deep sedation has not been studied.

According to the American Society of Anesthesiologist standards for basic monitoring, continuous capnography is required for all patients undergoing general anesthesia but it is optional for MAC/sedation cases. The need for CO2 monitoring has been studied by other medical specialties that use procedural sedation, including gastroenterology (12) and emergency medicine (13, 14) and many specialties now recommend capnography as a standard monitor.

Patients receiving supplemental oxygen may experience significant persistent hypoventilation leading to progressive hypercarbia and acidosis which may go undetected for a significant time interval since the routinely monitored SpO2 may be maintained within normal range. A recent study has shown that despite the fact that end tidal CO2 is reliable in detecting apnea , increasing oxygen flow rates decrease the amplitude of measured CO2, probably via dilution, making the quantitative value less reliable as an assessment of adequacy of ventilation (15). Furthermore, during hypoventilation there is reduced alveolar ventilation and the end tidal CO2 is not a true reflection of arterial CO2.

Transcutaneous measurement of PCO2(PtcCO2) is a non-invasive method of measuring PCO2 that has been used much less frequently due to technical difficulties with earlier transcutaneous electrodes. Preliminary studies of the reliability of the current PtcCO2 electrodes (TOSCA, Linde Medical Sensors, and Basel, Switzerland) have shown good correlation of arterial and transcutaneous measurements in both adult volunteers and anesthetized subjects (5). PtcCO2 is measured with a sensor attached by a low pressure clip to an earlobe. The sensor probe heats the earlobe to 42 degrees Celsius to enhance blood flow. The current sensors have also been evaluated in anesthetized children (7, 8), anesthetized adults (9, 10) and critically ill neonates (11) and all these studies revealed a good correlation between PtCO2 and PaCO2.

Detailed Description

A group of _40 patients scheduled to undergo Hysteroscopy surgery with deep sedation will be studied. Standard monitors will be utilized. Additionally a transcutaneous CO2 electrode will be attached to the ear lobe and a BIS monitor will be applied to the forehead.

The anesthetic management will be left to the discretion of the anesthesia provider (Anesthesia resident or CRNA, under the supervision of a faculty attending anesthesiologist).All patients will receive supplemental oxygen at 3L/ minute via nasal cannula, to maintain oxygen saturation greater than 90%.

Both the end tidal CO2 (ETCO2) and transcutaneous CO2 (TcCO2) (Linde Medical Sensors, Basel , Switzerland ) will be calibrated before use, according to the manufacturer's instruction.. The anesthesia provider will be blinded to the TcCO2 monitor but will have access to the ETCO2 values. The ETCO2 and TcCO2 values will be recorded simultaneously by an independent observer.

One arterial blood samples will be collected from each subject for measurement of PaCO2 at a deep level of sedation defined by a modified Ramsey score greater or equal to 5 (1= anxious/agitated/restless; 2= cooperative/oriented/tranquil; 3= drowsy/responds to commands only; 4= brisk response to shaking/loud sound; 5= sluggish response to shaking/loud sound; 6= no response) The ETCO2 and .TcCO2 will be recorded throughout the time of obtaining the blood sample every 15 seconds and the mean value will be used for comparison. Hypoventilation will be defined as a PaCO2 level greater than 45mmHg.

Sedation score (OASS) will be recorded on admission to recovery area. Time to meet discharge criteria will be recorded.

The experimental procedures: ABG draw, ETCO2 monitor placement on the ear, 2 Ramey scale assessments.

Study Type  ICMJE Interventional
Study Phase  ICMJE Not Applicable
Study Design  ICMJE Allocation: Non-Randomized
Intervention Model: Single Group Assignment
Masking: None (Open Label)
Primary Purpose: Diagnostic
Condition  ICMJE
  • Surgery
  • Hypoventilation
Intervention  ICMJE Other: Arterial blood draw
One arterial blood draw
Study Arms  ICMJE Experimental: All participants
All participants, one arterial blood draw
Intervention: Other: Arterial blood draw
Publications *

*   Includes publications given by the data provider as well as publications identified by Identifier (NCT Number) in Medline.
Recruitment Information
Recruitment Status  ICMJE Completed
Actual Enrollment  ICMJE
 (submitted: August 6, 2009)
Original Estimated Enrollment  ICMJE Same as current
Actual Study Completion Date  ICMJE August 2009
Actual Primary Completion Date August 2009   (Final data collection date for primary outcome measure)
Eligibility Criteria  ICMJE

Inclusion Criteria:

  • Age>18 years of age
  • Sex: Non-pregnant, Female
  • ASA PS: I, II
  • Surgery: Elective Hysteroscopy surgery
  • Consent: Obtained

Exclusion Criteria:

  • Age < 18 years old
  • Patients who refuses participation
  • History of lung disease
  • History of Obstructive sleep apnea
Sex/Gender  ICMJE
Sexes Eligible for Study: Female
Ages  ICMJE 18 Years and older   (Adult, Older Adult)
Accepts Healthy Volunteers  ICMJE No
Contacts  ICMJE Contact information is only displayed when the study is recruiting subjects
Listed Location Countries  ICMJE United States
Removed Location Countries  
Administrative Information
NCT Number  ICMJE NCT00954733
Other Study ID Numbers  ICMJE STU00004382
Has Data Monitoring Committee No
U.S. FDA-regulated Product Not Provided
IPD Sharing Statement  ICMJE Not Provided
Responsible Party Gildasio De Oliveira, Northwestern University
Study Sponsor  ICMJE Northwestern University
Collaborators  ICMJE Not Provided
Investigators  ICMJE
Study Director: Robert McCarthy, PharmD Northwestern University
PRS Account Northwestern University
Verification Date June 2014

ICMJE     Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP