Pressor Response
Conditions
Keywords
Dexmedetomidine, pressor response, optimum dose
Brief summary
Direct laryngoscopy and tracheal intubation are usually associated by hemodynamic changes due to increased sympathoadrenal activity which could precipitate serious negative effects in compromised patients . The pressor response could be blunted by dexmedetomidine which is a selective alpha 2 agonist which might provide hemodynamic stability during tracheal intubation.
Detailed description
Various drugs include local anesthetics, beta-blockers, calcium channel blockers, and narcotic analgesics have been tried to blunt the laryngoscopy and intubation response, with varied success. Dexmedetomidine is a potent and highly selective alpha-2 receptor agonist with sympatholytic, sedative, amnestic, and analgesic properties. Its various effects have led to its increasing use for reducing anesthetic and analgesic requirements in the perioperative period. It inhibits sympathetic activity thus terminating the pain signals and thereby blunts the pressor response associated with laryngoscopy and endotracheal intubation. Electrical cardiometry is recently introduced for assessment of many cardiovascular variables and continuously applicable method of cardiac output (CO), stroke volume (SV), and other hemodynamic parameters monitoring. Its use is growing because it is non-invasive, shows reliability in CO measurements and can be used as a continuous bedside monitor Although different doses of dexmedetomidine (0.5- 2.0 μg/kg) have been used in various studies which suggested its efficacy in blunting the hemodynamic pressor response , However, no studies to the best of our knowledge had incorporated CO monitoring for detection of minimal hemodynamic changes during laryngoscopy and endotracheal intubation which can be best achieved by using Cardiometry monitor. In this study, we will compare two doses of dexmedetomidine for prophylaxis against pressor response of ETI using cardiometry.
Interventions
this group will receive single dose of dexmedetomidine 0.5 mcg /kg in 50 ml normal saline over 10 min IV infusion
Sponsors
Theodor Bilharz Research Institute
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)
Intervention model description
The aim of our study is to assess and compare the efficacy of two different doses of dexmedetomidine (0.5 μg/kg and 1.0 μg/ kg) to find out its optimal dose in attenuation of hemodynamic pressor response to laryngoscopy and intubation with the use of Cardiometry for continuous CO monitoring beat by beat.
Eligibility
Sex/Gender
ALL
Age
18 Years to 60 Years
Healthy volunteers
No
Inclusion criteria
1 - ASA physical status 1-2. 2. Age 18- 60 years old of both sexes. 3. Patients undergoing elective surgery under general anesthesia and tracheal intubation.
Exclusion criteria
1. Age < 18 years and ≥ 60 years 2. Pregnancy 3. Emergency surgery or full stomach 4. Renal or Hepatic patients 5. Patients with suspected difficult airway {e.g., high neck circumference, high body mass index (above 30 kg/m2), airway masses, mouth scars, neck scars, limited neck extension or history of snoring. 6. Total duration of laryngoscopy will be noted and in cases where duration exceeded 15 sec the case will be excluded from the study. 7. Any patient on regular intake of beta blockers or calcium channel blockers 8. Patients with any known hypersensitivity or contraindication to dexmedetomidine, 9. Patients with significant neurological, psychiatric, or neuromuscular disorders.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Heart rate measurment | after 1 minute of successful tracheal intubation | single measurement after intubation |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| cardiac output | from the start of induction of anesthesia till 5 minutes after successful tracheal intubation | serial measurements every 1 minute |
Countries
Egypt
Outcome results
None listed