Content area
Full Text
ABSTRACT:
Fentanyl is an opioid with multiple routes of administration, including intrathecal administration. The intrathecal use of fentanyl was started in the 1970s and is currently utilised in combination with general anaesthesia or as an adjuvant to local anaesthesia in prolonging the duration of analgesia and providing more effective post-operative analgesia. It exerts its action via mu receptors in the spinal cord and its analgesic effects by reducing the release of excitatory nociceptive neurotransmitters, gamma-aminobutyric acid, and glycine. Intrathecal fentanyl is used in various clinical settings, including perioperative pain management, day case surgery, obstetric practice (e.g., caesarean section), gynaecological surgeries, and major joint replacement surgeries. Specific side effects are associated with using intrathecal fentanyl. These include pruritus, respiratory depression, urinary retention, and hypotension. Amongst these side effects, pruritus is most commonly encountered. Intrathecal fentanyl has a comprehensive pharmacological and clinical profile, the understanding of which makes it a valuable opioid analgesic in anaesthesia and pain management.
KEYWORDS: Fentanyl, Opioid, Intrathecal, Lipophilic, Analgesia, Pain management, Surgery, Anesthesia.
INTRODUCTION:
Fentanyl is a phenylpiperidine derivative and a synthetic opioid. Its potency is approximately 75 to 125 times more than morphine1. It is widely used in current anaesthesia practices and pain therapy. Dr. Paul Jansen, the founder of Jansen Pharmaceutica, synthesized fentanyl in the late 1950s through experimentation with meperidine. Dr. George De Castro, an anaesthesiologist based in Brussels, conducted its initial clinical evaluation. By the early to mid-1960s, fentanyl gained significant usage in Western European nations, gradually attaining global popularity in subsequent years2. The intrathecal use of opioids was first described by Nicolae Racoviceanu-Piteşt in Paris in 19013. Pert and Snyder's discovery of opioid receptors in 1973, followed by dorsal horn opioid receptor identification in 1977, resulted in further comprehension of intrathecal opioids. In 1976 evidence provided by Yaksh showed that opioids have a direct impact on the spinal cord to modulate nociceptive stimuli.
In 1979 a ground-breaking technique of administering morphine intrathecally in a cohort of eight patients with genitourinary malignancies was demonstrated by Wang4.
In current practices, various intrathecal opioids are used in conjunction with general anaesthesia and local anaesthesia5. Several recommendations have been made by Enhanced Recovery Programs (ERPs), one of which includes provision of adequate post operative analgesia6. Various adjuvants, both opioids and...