Effects of remifentanil and alfentanil on cardiovascular responses to tracheal intubation

Introduction: Laryngoscopy and tracheal intubation necessitate to start a surgery and induction of general anesthesia as well as the maintenance of the air way and to provide ventilation. However, Laryngoscopy and tracheal intubation may lead to hemodynamic response that appear with the symptoms of hypertension tachycardia, arrhythmia and myocardial ischemia and results in myocardial infarction and CVA. The present clinical trial study compared the effect of two rapid-onset narcotic, remifentanil and alfentanil on the hemodynamic responses to laryngoscopy and tracheal intubation. Methods: We studied 80 patients aged 20-50 (ASA I & II) as candidates to elective surgery with general anesthesia. The patients were randomly divided into two groups of 40 with the similar induction. The first group received remifentanil 1&micro;gr/kg and the second group alfentanil 15 &micro;gr/kg one minute before induction. Systolic, diastolic, mean arterial blood pressure and heart rate was measured and recorded before induction, after the injection of drugs, after tracheal intubation, three and five minutes after tracheal intubation. The data were analyzed using descriptive and analytical statistics. Results: Immediately, following the administration of narcotic and induction drug, systolic, diastolic and mean arterial pressure decreased significantly in two groups (p<0.05), but, heart rate increased in both groups which this increase was not statistically significant. After laryngoscopy and tracheal intubation all hemodynamic variants (except heart rate) increased (on basic level) and slowly decreased after three minutes in such a way that all hemodynamic variants returned to the level before intubation, in the fifth minute after intubation. Conclusion: Both remifentanil and alfentanil decreased hemodynamic variants due to laryngoscopy and tracheal intubation. These drugs could be used safely to control hemodynamic responses which occur following tracheal intubation