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Monitoring of Exhaled Carbon Monoxide to Promote Pre-operative Smoking Cessation

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ClinicalTrials.gov Identifier: NCT01014455
Recruitment Status : Completed
First Posted : November 17, 2009
Results First Posted : August 22, 2011
Last Update Posted : August 22, 2011
Sponsor:
Information provided by:
Mayo Clinic

Study Type Interventional
Study Design Allocation: Randomized;   Intervention Model: Parallel Assignment;   Masking: None (Open Label);   Primary Purpose: Treatment
Condition Smoking
Interventions Behavioral: Informing surgical patients about CO monitoring
Behavioral: a brief intervention recommending preoperative abstinence from smoking
Enrollment 169
Recruitment Details Cigarette smokers scheduled for elective non-cardiac surgery were recruited from the preoperative evaluation clinic at Mayo Clinic Rochester.
Pre-assignment Details Inform consent was obtained after data collection(approved by the IRB) because informing patients of the study at time of enrollment would have required providing information making it impossible to evaluate the hypothesis. Study records from patients who declined informed consent (n=14) were destroyed and are not included in the analysis.
Arm/Group Title CO Reminder no CO Reminder
Hide Arm/Group Description A brief intervention that recommends preoperative fasting from cigarettes and that informs patients that their smoking status will be checked before surgery using inhaled CO monitoring will decrease their exposure to cigarette smoke prior to surgery a brief intervention that recommends fasting but does not mention that CO will be checked
Period Title: Overall Study
Started 82 87
Completed 82 87
Not Completed 0 0
Arm/Group Title CO Reminder no CO Reminder Total
Hide Arm/Group Description A brief intervention that recommends preoperative fasting from cigarettes and that informs patients that their smoking status will be checked before surgery using inhaled CO monitoring will decrease their exposure to cigarette smoke prior to surgery a brief intervention that recommends fasting but does not mention that CO will be checked Total of all reporting groups
Overall Number of Baseline Participants 82 87 169
Hide Baseline Analysis Population Description
[Not Specified]
Age, Categorical  
Measure Type: Count of Participants
Unit of measure:  Participants
Number Analyzed 82 participants 87 participants 169 participants
<=18 years
0
   0.0%
0
   0.0%
0
   0.0%
Between 18 and 65 years
66
  80.5%
70
  80.5%
136
  80.5%
>=65 years
16
  19.5%
17
  19.5%
33
  19.5%
Age Continuous  
Mean (Standard Deviation)
Unit of measure:  Years
Number Analyzed 82 participants 87 participants 169 participants
53  (12) 53  (12) 53  (12)
Sex: Female, Male  
Measure Type: Count of Participants
Unit of measure:  Participants
Number Analyzed 82 participants 87 participants 169 participants
Female
40
  48.8%
47
  54.0%
87
  51.5%
Male
42
  51.2%
40
  46.0%
82
  48.5%
Region of Enrollment  
Measure Type: Number
Unit of measure:  Participants
United States Number Analyzed 82 participants 87 participants 169 participants
82 87 169
1.Primary Outcome
Title Preoperative Carbon Monoxide Levels
Hide Description [Not Specified]
Time Frame the morning of surgery
Outcome Measure Data Not Reported
2.Primary Outcome
Title Exhaled CO Level Measured Immediately Prior to Surgery
Hide Description On the morning of surgery, as matter of clinical routine all patients receiving surgery requiring anesthesia services at one of the two main surgical facilities at Mayo Clinic Rochester and who self-report as a current smoker are asked about their typical cigarette consumption (cigarettes per day), if they have smoked cigarettes today, and have their exhaled CO levels measured (Micro Smokerlyzer; Bedfont, United Kingdom). This information is entered into the clinical record. The CO monitors are maintained by the Division of Respiratory Therapy, including regular calibration.
Time Frame The median time from study assessment at POE to surgery was 1 day with an interquartile range of 1 to 3 days.
Show Outcome Measure DataHide Outcome Measure Data
Hide Analysis Population Description
5 participants did not complete CO measures and were excluded from the analysis of primary outcome
Arm/Group Title CO Reminder no CO Reminder
Hide Arm/Group Description:
A brief intervention that recommends preoperative fasting from cigarettes and that informs patients that their smoking status will be checked before surgery using inhaled CO monitoring will decrease their exposure to cigarette smoke prior to surgery
a brief intervention that recommends fasting but does not mention that CO will be checked
Overall Number of Participants Analyzed 80 84
Mean (Standard Deviation)
Unit of Measure: ppm
9.7  (8.0) 9.3  (6.6)
Show Statistical Analysis 1 Hide Statistical Analysis 1
Statistical Analysis Overview Comparison Group Selection CO Reminder, no CO Reminder
Comments [Not Specified]
Type of Statistical Test Superiority or Other
Comments [Not Specified]
Statistical Test of Hypothesis P-Value 0.672
Comments [Not Specified]
Method t-test, 2 sided
Comments [Not Specified]
Time Frame [Not Specified]
Adverse Event Reporting Description [Not Specified]
 
Arm/Group Title CO Reminder no CO Reminder
Hide Arm/Group Description A brief intervention that recommends preoperative fasting from cigarettes and that informs patients that their smoking status will be checked before surgery using inhaled CO monitoring will decrease their exposure to cigarette smoke prior to surgery a brief intervention that recommends fasting but does not mention that CO will be checked
All-Cause Mortality
CO Reminder no CO Reminder
Affected / at Risk (%) Affected / at Risk (%)
Total   --/--   --/-- 
Show Serious Adverse Events Hide Serious Adverse Events
CO Reminder no CO Reminder
Affected / at Risk (%) Affected / at Risk (%)
Total   0/0   0/0 
Show Other (Not Including Serious) Adverse Events Hide Other (Not Including Serious) Adverse Events
Frequency Threshold for Reporting Other Adverse Events 0%
CO Reminder no CO Reminder
Affected / at Risk (%) Affected / at Risk (%)
Total   0/0   0/0 
Study subjects received the additional questionnaire on smoking behavior, which itself could heighten awareness of perioperative tobacco use issues and could be viewed as an additional intervention.
Certain Agreements
All Principal Investigators ARE employed by the organization sponsoring the study.
Results Point of Contact
Name/Title: David O. Warner MD
Organization: Mayo Clinic
Phone: 5072846277
Responsible Party: David O. Warner, Mayo Clinic
ClinicalTrials.gov Identifier: NCT01014455     History of Changes
Other Study ID Numbers: 09-006998
First Submitted: November 13, 2009
First Posted: November 17, 2009
Results First Submitted: July 25, 2011
Results First Posted: August 22, 2011
Last Update Posted: August 22, 2011