The Effect of Nasal Continuous Positive Airway Pressure (N-CPAP) on Arterial pCO2 During Spinal Anesthesia

Study Overview
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Brief Summary
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The proposed study intends to investigate several aspects of the respiratory effects of intravenous sedation of patients undergoing spinal anesthesia for knee replacement surgery. The study will include assessment of PaCO2 during the intraoperative period. PaCO2 is expected to be elevated as a result of intravenous sedation and postural factors. Further, the study will investigate how application of Nasal Continuous Positive Airway Pressure (N-CPAP) may impact PaCO2.

Official Title
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The Effect of Nasal Continuous Positive Airway Pressure (N-CPAP) on Arterial pCO2 During Spinal Anesthesia With Intravenous Sedation for Total Knee Arthroplasty

Conditions
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Knee Replacement Surgery

Intervention / Treatment
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* Other: Nasal Continuous Positive Airway Pressure (NCPAP)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: American Society of Anesthesiology Class I, II, or III patients Age over 21 years and under 70 years Planned surgical procedure is total knee arthroplasty (TKA) to be performed at Cape Fear Hospital Body Mass Index less than 40 The patient and their attending anesthesiologist select spinal anesthesia with intravenous sedation, intrathecal morphine, and femoral nerve block as the preferred anesthesia plan Exclusion Criteria: Prior diagnosis of Obstructive Sleep Apnea based upon sleep study History of Stroke with residual neurologic deficit Prior diagnosis of Emphysema, Chronic Bronchitis, Chronic Obstructive Pulmonary Disease, or Asthma, or other chronic lung disease Recent history of significant nasal obstruction, epistaxis, or facial abnormality that may interfere with proper fit of a nasal CPAP mask Pregnancy Mental or other disability preventing a patient from personally giving informed consent Chronic narcotic or benzodiazepine treatment or dependency Allergy to Midazolam, Fentanyl, or Propofol Severe upper respiratory infection within the past three weeks

Ages Eligible for Study
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Minimum Age: 21 Years
Maximum Age: 69 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Supportive Care
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: NCPAP Group<br>Group of patients that do receive NCPAP treatment | Other: Nasal Continuous Positive Airway Pressure (NCPAP)<br>* Subjects will receive NCPAP<br>|
| No Intervention: No NCPAP<br>subjects will not receive NCPAP | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Arterial Blood Gas (ABG) test to investigate the breathing effects on patients receiving CPAP treatment during spinal anesthesia for knee replacement. | The TEST patients will receive CPAP treatment immediately after the first ABG specimen is drawn. After collection of the second ABG specimen, the anesthesia team may elect to remove the N-CPAP mask or maintain it as deemed best. The CONTROL patients will not receive CPAP treatment. | ABG will be collected five minutes after surgical skin incision and the second specimen will be collected exactly 30 minutes later. | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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NCPAP