Anesthesia and analgesia
-
Anesthesia and analgesia · May 2002
Randomized Controlled Trial Clinical TrialThe absence of acute tolerance during remifentanil infusion in volunteers.
The development of acute opioid tolerance in humans remains controversial. We tested the hypothesis that continuous remifentanil infusion leads to rapid development of opioid tolerance. Twenty healthy male volunteers were enrolled onto a randomized, placebo-controlled, double-blinded, cross-over design study to receive a 3 h continuous infusion of remifentanil (0.08 microg x kg(-1) x min(-1)) or saline. Test procedures included determination of pain perception thresholds and pain tolerance thresholds to heat and cold and neuroselective sine wave constant current at 5 Hz and 250 Hz. Test procedures were performed at baseline and then repeated at 25, 55, 85, 115, and 160 min (heat/cold) and at 35, 65, 95, 125, and 170 min (electrical current) during infusion. No significant decrease of the pain threshold devolutions between 55 and 180 min after the start of infusion of remifentanil could be detected. In conclusion, no development of acute opioid tolerance was observed during constant remifentanil infusion of 3 h in volunteers. ⋯ The opioid remifentanil was applied to 20 volunteers at a constant concentration for 3 h while pain thresholds to temperature and current were repeatedly assessed. Our aim was to study whether thresholds decrease over time because of the rapid development of opioid tolerance. No development of rapid opioid tolerance was observed.
-
Anesthesia and analgesia · May 2002
Randomized Controlled Trial Clinical TrialCaudal clonidine prolongs analgesia from caudal S(+)-ketamine in children.
We performed a prospective randomized double-blinded study to test preservative-free S(+)-ketamine alone or in combination with clonidine for intra- and postoperative caudal blockade in pediatric surgery over a 24-h period. Fifty-three children (1-72 mo) scheduled for inguinal hernia repair were caudally injected with either S(+)-ketamine 1 mg/kg alone (Group K) or with additional clonidine (Group C1 = 1 microg/kg; Group C2 = 2 microg/kg) during sevoflurane anesthesia via a laryngeal mask. Intraoperative monitoring included heart rate, blood pressure, and pulse oximetry; postoperative monitoring included a pain discomfort scale and a sedation score. No additional analgesic drugs were required during surgery. The mean duration of postoperative analgesia was 13.3 +/- 9.2 h in Group K, 22.7 +/- 3.5 h in Group C1, and 21.8 +/- 5.2 h in Group C2 (P < 0.0001, Group K versus other groups). Groups C1 and C2 received significantly fewer analgesics in the postoperative period than Group K (15% and 18% vs 63%; P < 0.01). The three groups had similar postoperative sedation scores. We conclude that the combination of S(+)-ketamine 1 mg/kg with clonidine 1 or 2 microg/kg for caudal blockade in children provides excellent analgesia without side effects over a 24-h period. ⋯ Caudally administered preservative-free S(+)-ketamine combined with 1 or 2 microg/kg clonidine provides excellent perioperative analgesia in children and has minimal side effects.
-
Anesthesia and analgesia · May 2002
Review Case ReportsDystonic reaction to propofol attenuated by benztropine (cogentin).
Neuroexcitatory movements associated with propofol anesthesia are well recognized. Here we report on the successful use of benztropine (2 mg) to abolish abnormal dystonic movements after propofol anesthesia. Forty-five case reports are reviewed, and a treatment strategy for abnormal movements during propofol anesthesia is provided.
-
Anesthesia and analgesia · May 2002
Randomized Controlled Trial Comparative Study Clinical TrialTarget-controlled versus manually-controlled infusion of propofol for direct laryngoscopy and bronchoscopy.
Few studies have compared the clinical profile of target-controlled infusions of propofol with that of manually-controlled infusions. Fifty-four ASA physical status I or II patients scheduled for an elective otorhinolaryngology endoscopy performed under general anesthesia with spontaneous ventilation were enrolled in this prospective randomized study to compare the clinical outcome of such administrations. Before induction, all patients received a single alfentanil bolus dose (10 microg/kg). Propofol administration was adapted to maintain absence of movement, hemodynamic stability, and efficient spontaneous ventilation. When compared with the Manually-Controlled Infusion group, in the Target-Controlled Infusion group there were fewer movements at insertion of the laryngoscope (14.8% vs. 44.4%), improved hemodynamic stability (largest variations of mean arterial blood pressure <10% of control values, versus 20%), fewer episodes of apnea, and less respiratory acidosis after endoscopy (pH = 7.37 +/- 0.05 and PaCO(2) = 50 +/- 7 mm Hg versus pH = 7.28 +/- 0.06 and PaCO(2) = 58 +/- 9 mm Hg); the recovery was also shorter (time to opening eyes or verbal response, 4.6 +/- 2.0 min and 6.8 +/- 2.5 min versus 10.8 +/- 7.3 min and 15.7 +/- 7.1 min). Propofol consumption was comparable in the two groups. Targeting the effect-site concentration improved the time course of the propofol drug effect during direct laryngoscopy performed during spontaneous ventilation when compared with manual infusion. ⋯ This study compares the clinical profile of propofol anesthesia for direct laryngoscopy with spontaneous ventilation when the drug is administered either as a manually controlled infusion or by targeting the effect-site concentration through a target-controlled infusion (TCI) device. TCI improves the time course of propofol effects.
-
Anesthesia and analgesia · May 2002
Randomized Controlled Trial Clinical TrialThe efficacy of premedication with celecoxib and acetaminophen in preventing pain after otolaryngologic surgery.
Non-opioid analgesics are often used to supplement opioids for the management of perioperative pain. In this randomized, double-blinded, placebo-controlled study, we examined the effects of acetaminophen and a cyclooxygenase type-2 inhibitor, celecoxib, when administered alone or in combination, before elective otolaryngologic surgery in 112 healthy outpatients. Subjects were assigned to 1 of 4 study groups: Group 1, placebo (vitamin C, 500 mg per os [PO]); Group 2, acetaminophen 2000 mg PO; Group 3, celecoxib 200 mg PO; or Group 4, acetaminophen 2000 mg and celecoxib 200 mg PO. All patients received a standardized anesthetic technique. During the postoperative period, pain was assessed using a 10-point verbal rating scale. Recovery times, the need for rescue analgesics, side effects, and patient satisfaction scores were also recorded. The combination of acetaminophen and celecoxib was significantly more effective than placebo in reducing postoperative pain. Celecoxib, when administered alone or in combination with acetaminophen, improved patients' satisfaction with their postoperative analgesia. With the combination of acetaminophen and celecoxib, an additional expenditure of $6.16 would be required to obtain complete satisfaction with postoperative pain management in one additional patient who would not have been completely satisfied if he/she had received the placebo. However, oral celecoxib or acetaminophen alone was not significantly more effective than placebo in reducing postoperative pain when administered before surgery. We conclude that oral premedication with a combination of acetaminophen (2000 mg) and celecoxib (200 mg) was highly effective in decreasing pain and improving patient satisfaction after outpatient surgery. ⋯ Oral premedication with a combination of acetaminophen (2000 mg) and celecoxib (200 mg) was effective in decreasing pain and improving patient satisfaction after otolaryngologic surgery. However, acetaminophen (2000 mg) or celecoxib (200 mg) alone was not significantly more effective than placebo in reducing postoperative pain.