Dexmedetomidine for the Control of Post-Operative Pain in Thoracotomy Patients

Study Overview
=================
Brief Summary
-----------------
The purpose of this study is to evaluate the safety, efficacy, hemodynamic and respiratory stability of a low-dose of dexmedetomidine infusion in post-operative surgical in-patients undergoing thoracic surgery after discharge from PACU or ICU.

Detailed Description
-----------------
Dexmedetomidine has sedative and analgesic properties that may reduce the opioid requirement in post-operative patients, thereby decreasing the chance of post-operative respiratory depression that occurs with opioid administration. In addition, patients may be more alert with less opioid medication. Currently, dexmedetomidine is not approved for use longer than twenty-four hours and must only be administered in the Intensive Care Unit where patients can be continuously monitored. This is a prospective, double-blinded, control group pilot study. One group (the control group) will receive a normal saline infusion and the second group (the treatment group) will receive low-dose Dexmedetomidine for up to 24 hours after they are admitted to an open nursing unit (not an Intensive Care Unit). During the surgery, the anesthesiologist will administer dexmedetomidine during the surgical procedure after an optional loading dose. All patients will receive pain medication using a Patient Controlled Analgesia (PCA) pump as per standard practice. In addition, if the physician deems necessary, an On-Q Pain Pump will deliver local anesthetic surrounding the incision under direction of the surgeon. Before discharge from the PACU or ICU, each subject will receive either low-dose dexmedetomidine or normal saline using a continuous infusion pump for up to 24 hours after the subject is discharged from either the PACU or the ICU to an open nursing unit. While on the open nursing unit patient vital signs, oxygen saturation, Ramsay score and pain score will recorded every two hours until the treatment drug is stopped.

Official Title
-----------------
Post-Operative Infusion of Low-Dose Dexmedetomidine for the Control of Post-Operative Pain in Thoracotomy Patients: A Randomized, Double-Blind, Controlled Pilot Study

Conditions
-----------------
Post-operative Pain, Respiratory Depression

Intervention / Treatment
-----------------
* Drug: Dexmedetomidine
* Other: Placebo (Normal Saline)


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: American Society of Anesthesiologists (ASA) class I, II or III Undergoing thoracic surgery on an inpatient basis Age 18 up to 85 years of age Exclusion Criteria: Subject is pregnant and/or lactating Subject has a serious Central Nervous System (CNS)pathology/trauma that, per clinical judgment of the investigator, precludes responsiveness or survival. Subject for whom alpha-2 agonists are contraindicated Subject meets any of the following cardiovascular criteria: Acute unstable angina (defined during current hospital stay) Suspicion of acute myocardial infarction. Considered to have a left ventricular ejection fraction of less than 30%.Decision to exclude is predicated in the Investigator's opinion, and may be based on any combination of acute presentations, recently preformed diagnostic studies, or a history that suggests poor cardiac function. Pulmonary congestion of a non-cardiac origin or mild congestive failure primarily attributable to etiologies other than poor ventricular function are not exclusion criteria. Subject has participated in a trial with any experimental drug within 30 days prior to enrollment in the study, or has ever been enrolled in this study. Subject is unable to undergo any procedures required by the protocol. Subject has acute hepatitis, a history or presence of chronic hepatitis, and /or has had a positive result for Hepatitis B surface antigen test. Subject requires dialysis (e.g., hemodialysis, peritoneal dialysis, CVVHD). Subject has a known, uncontrolled seizure disorder. Subject has a known psychiatric illness that could confound a normal response to sedative treatment. Subject is terminally ill with a life duration expectancy of < 60 days. Subject has a history of Obstructive Sleep Apnea. Oxygen saturation is < 90% on room air. Subject is on beta blocker medication.

Ages Eligible for Study
-----------------
Minimum Age: 18 Years
Maximum Age: 85 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Placebo Comparator: Normal Saline<br>One group (placebo comparator) will receive a normal saline infusion, set at a rate as if it were the active drug. | Other: Placebo (Normal Saline)<br> <br> |
| Active Comparator: Dexmedetomidine<br>The second group (the study group) will receive a continuous infusion of dexmedetomidine titrated from 0.1 - 0.5 mics/kg/h to control pain for up to 24 hours after they are admitted to an open nursing unit after discharge from the PACU or ICU | Drug: Dexmedetomidine<br>* Dexmedetomidine titrated over 24 hours<br>* Other names: Precedex, Dexdor Titrated 0.1 to 0.5 ug.kg.h-1;|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Measure Any Reduction in the Amount of Opioid Administered to Patients in the Dexmedetomidine Study Arm. | To measure the amount of opioid use requested by patients enrolled in the dexmedetomidine study arm during the observation period of 24 hours, up to 30 hours per patient. | An average of 24 hours, up to 30 hours per patient | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Measure the Amount of Respiratory Depression in Each Groups | Respiratory depression and deep levels of sedation can occur when morphine patient-controlled analgesia is prescribed for postoperative patients. In this secondary outcome measure, it was hypothesized that the addition of a dexmedetomidine infusion to the postoperative pain management protocol would reduce the amount of morphine delivered by a PCA pump while providing adequate analgesia. Data are reported for the time period 6 to 16 hours. However, the subjects were on the study for an average of 24 hours, up to 30 hours. | Hours 6 to 16 | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
Dexmedetomidine, Sedation, Opioid, Respiratory depression