Hypotension remifentanil

Remifentanil by infnsion (n = 49) has been compared with titrated bolnses of pethidine (n = 51) in a randomized, donble-blind stndy in 100 patients undergoing outpatient colonoscopy (9). The incidences of tachycardia, hypotension, and nausea were significantly less with remifentanil than with pethidine, but there were higher anxiety and pain scores with remifentanil. However, the study was a comparison of two opioids with different pharmacokinetic profiles, which makes it very difficult to achieve equipotent doses for the purpose of comparison. 

In a prospective randomized comparison of combined sevoflurane plus remifentanil with combined fentanyl plus etomidate for induction of anesthesia in 10 patients with ischemic heart disease, 3 of the 20 patients given sevoflurane plus remifentanil developed severe bradycardia (heart rate less than 40) and one developed asystole, but the difference between the two groups did not reach statistical significance (20). Therefore, in patients with ischemic heart disease remifentanil should be used with caution, and concurrent administration of glycopyr-rolate 0.2 mg is advisable to reduce the incidence of bradycardia, hypotension, or both, without increasing the heart rate. 

Remifentanil is liable to cause respiratory depression in children (33,34), as well as muscle rigidity, hypotension, and bradycardia, without increasing the incidence of gastrointestinal symptoms (35). 

In a double-blind, randomized study of 178 patients scheduled for major thoracic, intra-abdominal, and orthopedic surgery, a high dose of remifentanil (bolus dose of 1 microgram/kg followed by 1 microgram/kg/minute) was compared with a low dose (bolus dose 1 microgram/kg followed by 0.5 micrograms/kg/minute) (39). In this study, intraoperative hypotension (30% and 27% respectively)... 

The manufacturers of remifentanil and sufentanil caution that cardiovascular effects (bradycardia and hypotension) may be greater in patients also taking calcium-channel blockers. ... 

Susceptibflity factors Age The use of remifentanil in neonates and premature infants has been reviewed. Adverse reactions were similar to other opioids (bradycardia, hypotension, respiratory depression, chest waU rigidity, nausea, and vomiting) but were less frequent and less severe [177 ]. 

Rapid-sequence intubation remifentanil has been reported for use in heu of neuromuscular blockade during rapid sequence intubations and is reported to provide good to excellent intubating conditions with doses of 3-4 pg/kg given as a slow IV push. Notably, studies do not indicate chest wall rigidity or hypotension as problematic with this technique. 

High-dose infusion (starting doses 1-3 mg/kg per min) effectively attenuates response to major surgical stress, such as sternal spread, and is still associated with a rapid recovery profile. However, remifentanil may be associated with a higher incidence of intraoperative hypotension. 

Side effects remifentanil may cause adverse effects characteristic of p opioids, such as respiratory depression, bradycardia, hypotension, primitus, and skeletal muscle rigidity. 

Cardiovascular In 132 patients undergoing elective craniotomy, remifentanil was in 12 different doses (0.10-0.21 micrograms/kg/ minute) was associated with hypotension at a median dose of 0.13 micrograms/kg/minute and bradycardia at 0.17 micrograms/kg/ minute [163 ]. 

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