The Effect of Ketamine in the Prevention of Hypoventilation in Patients Undergoing Deep Sedation Using Propofol and Fentanyl

Procedures performed under sedation have the same severity in regards to morbidity and mortality as procedures performed under general anesthesia1. The demand for anesthesia care outside the operating room has increased tremendously and it poses, according to a closed claim analysis, major risks to patients. Both closed claim analysis identified respiratory depression due to over sedation as the main risk to patients undergoing procedures under sedation. The major problem is that hypoventilation is only detected at very late stages in patients receiving supplemental oxygen. Besides the respiratory effects of hypoventilation, hypercapnia can also lead to hypertension, tachycardia, cardiac arrhythmias and seizures.

The incidence of anesthetized patients with obstructive sleep apnea has increased substantially over the last years along with the current national obesity epidemic. These patients are at increased risk of hypoventilation when exposed to anesthetic drugs. The context of the massive increase in procedural sedation and the extremely high prevalence of obstructive sleep apnea poses major respiratory risks to patients and it may, in a near future, increase malpractice claims to anesthesiologists. The development of safer anesthesia regimen for sedation are, therefore, needed. The establishment of safer anesthetics regimen for sedation is in direct relationship with the anesthesia patient safety foundation priorities. It addresses peri-anesthetic safety problems for healthy patient's. It can also be broadly applicable and easily implemented into daily clinical care. Ketamine has an established effect on analgesia but the effects of ketamine on ventilation have not been clearly defined. The investigators have demonstrated that the transcutaneous carbon dioxide monitor is accurate in detecting hypoventilation in patients undergoing deep sedation. Animal data suggest that when added to propofol in a sedation regimen, ketamine decreased hypoventilation when compared to propofol alone. It is unknown if ketamine added to a commonly used sedative agent (propofol) and fentanyl can decrease the incidence and severity of hypoventilation in patients undergoing deep sedation.

The investigators hypothesize that patients receiving ketamine, propofol and fentanyl will develop less intraoperative hypoventilation than patients receiving propofol and fentanyl.

The investigators also hypothesize that this effect will be even greater in patients with obstructive sleep apnea than patients without obstructive sleep apnea.

Significance: Respiratory depression due to over sedation was identified twice as the major factor responsible for claims related to anesthesia. The high prevalence of obstructive sleep apnea combined with more complex procedures done in outpatient settings can increase physical risks to patients and liability cases to anesthesiologists. The main goal of this project is to establish the effect of ketamine in preventing respiratory depression to patients undergoing procedures under deep sedation using propofol and fentanyl.

If the investigators can confirm our hypothesis, our findings can be valuable not only to anesthesiologist but also to other specialties (emergency medicine, gastroenterologists, cardiologists, radiologists) that frequently performed procedural sedation.

The research questions is; does the addition of ketamine prevent hypoventilation during deep sedation using propofol and fentanyl?

The hypotheses of this study: Ketamine will prevent hypoventilation during deep sedation cases.

Study Overview

• Status: Withdrawn
• Conditions: Hypercarbia
• Intervention / Treatment: Drug: Ketamine; Drug: Placebo

• Study Type: Interventional
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Illinois
    • Chicago, Illinois, United States, 60611
      • Prentice Womens Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 64 years (Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: Female

Description

Inclusion Criteria:

ASA I and II

• Age 18-64
• Females undergoing sedation procedures

Exclusion Criteria:

• Pregnant subjects
• Breastfeeding
• Patients or surgeon request
• Difficult airway

Drop Out:

• Patient or surgeon request
• Conversion to general anesthesia .Inability to obtain data from CO2 monitor.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Triple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Ketamine; Ketamine administered 0.5mg/kg followed by an infusion of 1.5mcg/kg/min.	Drug: Ketamine; Ketamine group receives 0.5mg/kg followed by an infusion of 1.5mcg/kg/min.; Other Names: Ketamine adminstration
Placebo Comparator: Placebo; Saline group will received the same volume in saline as the ketamine dose	Drug: Placebo; 0.9 % normal saline group receives same volume as the ketamine dose; Other Names: 0.9 % normal saline group receives same volume as ketamine dose

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
The total percentage time patients hypoventilate during the case	The total percentage time patients hypoventilate during the case	Day 1

Collaborators and Investigators

• Sponsor: Northwestern University
• Investigators: Principal Investigator: Gildasio De Oliveira, MD,MS, Northwestern University

Study record dates

Study Major Dates

• Primary Completion (Actual): March 1, 2014
• Study Completion (Actual): March 1, 2014

Study Registration Dates

• First Submitted: January 31, 2013
• First Submitted That Met QC Criteria: April 4, 2013
• First Posted (Estimate): April 5, 2013

Study Record Updates

• Last Update Posted (Estimate): May 8, 2014
• Last Update Submitted That Met QC Criteria: May 7, 2014
• Last Verified: May 1, 2014

More Information

Terms related to this study

• Keywords: Ketamine; Fentanyl; Intraoperative monitoring; Hypercarbia; TOSCA monitor
• Additional Relevant MeSH Terms: Respiratory Tract Diseases; Respiration Disorders; Signs and Symptoms, Respiratory; Respiratory Insufficiency; Hypoventilation; Hypercapnia; Physiological Effects of Drugs; Neurotransmitter Agents; Molecular Mechanisms of Pharmacological Action; Central Nervous System Depressants; Peripheral Nervous System Agents; Analgesics; Sensory System Agents; Anesthetics, Dissociative; Anesthetics, Intravenous; Anesthetics, General; Anesthetics; Excitatory Amino Acid Antagonists; Excitatory Amino Acid Agents; Ketamine
• Other Study ID Numbers: STU00068533