The influence of intrathecal fentanyl on the characteristics of subarachnoid block for Caesarean section

Abstract

SummaryWe have assessed the effect of two induction agents on tracheal intubating conditions after rocuronium 0.6 mg.kg À1 in unpremedicated patients undergoing simulated rapid sequence induction. Following pre-oxygenation, anaesthesia was induced with propofol up to 2.5 mg.kg À1 (n 35) or etomidate 0.3 mg.kg À1 (n 36), and further increments as required. After loss of verbal contact, cricoid pressure was applied and rocuronium was injected. Laryngoscopy was performed at 45 s and intubation attempted at 60 s after rocuronium had been given. Ninety-four per cent of patients in the propofol group had clinically acceptable (good or excellent) intubating conditions compared to only 75% in the etomidate group (p 0.025). Owing to coughing, one patient in the etomidate group could not be intubated on the first attempt. A greater pressor response also followed intubation after induction with etomidate. We conclude that etomidate and rocuronium alone cannot be recommended for intubation at 60 s under rapid sequence induction conditions. After a period of oxygenation an intravenous barbiturate followed immediately by a full dose of muscle relaxant have long been used to permit rapid tracheal intubation in the patient at risk of aspiration [1, 2]. Thiopentone and suxamethonium are traditionally used for this purpose. Rocuronium has been shown to be a suitable alternative to suxamethonium for rapid tracheal intubation [3]. Pharyngeal and laryngeal reflexes are more depressed by propofol than by other intravenous induction agents [4] and may create more favourable intubating conditions. Propofol is increasingly being used as the induction agent of choice for rapid tracheal intubation in patients who are haemodynamically stable [5]. The main problem concerning induction of anaesthesia with propofol is dose-related hypotension and this may preclude its use in the elderly and hypovolaemic patients [6][7][8][9].Of the current induction agents, etomidate causes the least haemodynamic disturbance and may be more suitable when cardiac stability is desirable [6, 7, 10]. We were interested to see if intubating conditions and cardiovascular changes under rapid sequence induction conditions were acceptable if anaesthesia was induced with etomidate and rocuronium, rather than with propofol and rocuronium. Patients and methodAfter obtaining approval from the hospital ethics committee and informed patient consent, we studied 71 adult patients aged 18-75 years, ASA grades I and II, undergoing elective surgery. Patients with potential airway problems were not studied. No patient had hepatic or renal impairment or was receiving any medication known to interact with neuromuscular blocking agents. Patients were unpremedicated and randomly allocated to receive either propofol or etomidate after a 3-min period of preoxygenation. The estimated induction dose in the propofol group was 2.5 mg.kg À1 , and 0.3 mg.kg À1 in the etomidate group. The agent was titrated over 30 s until verbal contact was lost. Further increments were given if required. H...

A prospective randomised double blind study of the comparison of two opioids- fentanyl and buprenorphine – as adjuvant to spinal bupivacaine in caesarean sections

“…15 But the magnitude of BP fall and use of ephedrine is similar in both the groups. These results are comparable to the findings of Khan et al, Dixit et al, Shaik et al [16][17][18] There was no change in neonatal APGAR scores among the groups, which were similar with the observations made by Hunt et al and Shendi et al 19,20 In our study, we found that Buprenorphine produced prolonged analgesia without increase in the incidence of side effects, when compared to fentanyl.…”

Comparison of clonidine and fentanyl as an adjuvant to bupivacaine in unilateral spinal anaesthesia

“…None of the patients required additional anxiolytics or sedatives intraoperatively. Similar results were also reported by Shende et al 20 …”

Effect of Adding Dexmedetomidine versus Fentanyl to Intrathecal Bupivacaine on Spinal Block Characteristics in Gynecological Procedures: A Double Blind Controlled Study

“…Fentanyl is a lipophillic µ-receptors agonist opioid. Intrathecally, fentanyl exerts its effect by combining with opioid receptors in the dorsal horn of spinal cord and may have a supra spinal spread and action [9,10] . Pain is frequently encountered during surgery on the female genital organs under spinal local anesthetics, intrathecal fentanyl when added to spinal local anesthetics reduces significantly visceral and somatic pain and this analgesic effect has been proved by many studies [11][12][13][14] .…”