Please select the eligibility criteria that correspond to the clinical trial below.
Title: The Effects of Intravenous Dexmedetomidine on Spinal Anesthesia Using Low Dose Diluted Bupivacaine for Transurethral Resection of Prostate
Brief Summary: Dexmedetomidine is a new selective and potent alpha-2 agonist. It has centrally acting anesthetic properties. It has been known that intrathecal addition of alpha-2 adrenergic agents result in prolongation of the duration of the sensory and motor blockade induced by hyperbaric bupivacaine. But the effects of intravenous dexmedetomidine on the spinal block was not evaluated. The aim of study is to assess the effect of intravenous dexmedetomidine on the low-dose spinal anesthesia for the transurethral surgery.


Options:
A: Inclusion Criteria:

Patients of 60 years or older who are planning to receive cardiac surgery (CABG and/or valve replacement surgery)

Exclusion Criteria:

Patients will be excluded if they meet any of the following criteria:

1. Refuse to participate;
2. Preoperative history of schizophrenia, epilepsia, Parkinson syndrome, or severe dementia;
3. Inability to communicate in the preoperative period because of severe visual/auditory dysfunction or language barrier;
4. History of brain injury or neurosurgery;
5. Preoperative sick sinus syndrome, severe bradycardia (HR \< 50 bpm), second-degree or above atrioventricular block without pacemaker;
6. Severe hepatic dysfunction (Child-Pugh class C);
7. Severe renal dysfunction (requirement of renal replacement therapy);
8. Other conditions that are considered unsuitable for participation.
B: Inclusion Criteria:

1. Are undergoing noncardiac surgery;
2. Are ≥ 45 years of age;
3. Are expected to require at least an overnight hospital admission after surgery; AND
4. Fulfill one or more of the following 5 criteria:

   * History of coronary artery disease
   * History of peripheral vascular disease
   * History of stroke
   * Undergoing major vascular surgery
   * Any 3 of the following 9 criteria:

     * undergoing major surgery (i.e. intraperitoneal, intrathoracic, retroperitoneal or major orthopedic surgery
     * history of congestive heart failure
     * transient ischemic attack
     * diabetes and currently taking an oral hypoglycemic agent or insulin
     * age ≥ 70 years
     * hypertension
     * serum creatinine \> 175 µmol/L (\> 2.0 mg/dL)
     * history of smoking within 2 years of surgery
     * undergoing urgent/emergent surgery

Exclusion Criteria:

1. Consumption of ASA within 72 hours prior to surgery
2. Hypersensitivity or known allergy to ASA or clonidine
3. Systolic blood pressure \< 105 mm Hg
4. Heart rate \< 55 beats per minute in a patient who does not have a permanent pacemaker
5. Second or third degree heart block without a permanent pacemaker
6. Active peptic ulcer disease or gastrointestinal bleeding within previous 6 weeks
7. Intracranial hemorrhage documented by neuro-imaging, in the 6 months prior to randomization. This does not include petechial hemorrhagic transformation of a primary ischemic stroke
8. Subarachnoid hemorrhage or epidural hematoma unless the event occurred more than 6 months prior to randomization and the offending aneurysm or arterial lesion has been repaired
9. Drug-eluting coronary stent in the year prior to randomization
10. Bare-metal coronary stent in the 6 weeks prior to randomization
11. Thienopyridine (e.g., clopidogrel, ticlopidine, prasugrel) or ticagrelor within 72 hours prior to surgery; or intent to restart a thienopyridine or ticagrelor during the first 7 days post-op; or currently taking an alpha-2 agonist, alpha methyldopa, monoamine oxidase inhibitors or reserpine;
12. Planned use - during the first 3 days after surgery - therapeutic dose anticoagulation or a therapeutic subcutaneous or intravenous antithrombotic agent
13. Undergoing intracranial surgery, carotid endarterectomy, or retinal surgery
14. Not consenting to participate in POISE-2 prior to surgery
15. Previously enrolled in POISE-2 Trial
C: Inclusion Criteria:

1. Adult (≥18 years of age);
2. American Society of Anesthesiologists (ASA) score I - IV inclusive;
3. Male or female. If female, subject is non-lactating and is either:

   1. Not of childbearing potential, defined as post-menopausal for at least 1 year or surgically sterile due to bilateral tubal ligation, bilateral oophorectomy or hysterectomy.
   2. Of childbearing potential but is not pregnant at time of baseline and is practicing one of the following methods of birth control: oral or parenteral contraceptives, double-barrier method, vasectomized partner, or abstinence from sexual intercourse.
4. Requiring awake fiberoptic (oral or nasal) intubation because of anticipated difficult airway. Subjects must meet at least one of the criteria listed below:

   Criteria for Assessing Difficult Airways

   i. History of difficult intubation

   ii. Anticipated difficult airway
   1. Prominent protruding teeth
   2. Small mouth opening
   3. Narrow mandible
   4. Micrognathia
   5. Macroglossia
   6. Short, muscular neck
   7. Very long neck
   8. Limited neck extension
   9. Congenital airway anomalies
   10. Obesity
   11. Known airway pathology
   12. Known airway malignancy
   13. Upper airway obstruction

   iii. Trauma
   1. Face
   2. Upper airway
   3. Cervical spine

   iv. Anticipated difficult mask ventilation

   v. Severe risk of aspiration

   vi. Respiratory failure

   vii. Severe hemodynamic instability
5. Subject (or subject's legally authorized representative) must voluntarily sign and date the informed consent.

Exclusion Criteria:

1. Previous exposure to any experimental drug within 30 days prior to study drug administration;
2. Central nervous system (CNS) disease with an anticipated increased intracranial pressure or cerebrospinal fluid (CSF) leak;
3. Uncontrolled seizure disorder and/or known psychiatric illness that could confound a normal response to sedative treatment;
4. Presence of acute alcohol intoxication;
5. Current (within 14 days of study entry) treatment with an α2-agonist or antagonist;
6. Subject for whom benzodiazepines, dexmedetomidine or other α2-agonists are contraindicated;
7. Subject received an IV or oral (PO) opioid within one hour or intramuscularly within four hours of the start of study drug administration;
8. Subject has acute unstable angina, laboratory confirmed acute myocardial infarction within the past 6 weeks, heart rate \<50 bpm, systolic blood pressure (SBP) \<90 mmHg, or complete heart block unless they have a pacemaker.
9. Subject has elevated serum glutamic pyruvate aminotransferase/alanine transaminase (SGPT/ALT) and/or Serum glutamic oxaloacetic transaminase/ aspartate aminotransferase (SGOT/AST) values of ≥2 times the upper limit of normal (ULN).
10. Subject has any other condition or factor which, in the Investigator's opinion, might increase the risk to the subject.
D: Inclusion Criteria:

* ASA class I or II
* Elective transurethral prostatectomy
* aged \> 20

Exclusion Criteria:

* Coagulation deficiency
* infection on the back
* Congestive heart failure or arrythmia
* Chronic alcoholic disease
* Antidepressants therapy

Answer: D