[Cohort study of remifentanil-induced hyperalgesia in postoperative patients].

OBJECTIVE: To investigate the incidence of remifentanil-induced hyperalgesia and screen for the relevant influencing factors in the post-operative patients. METHODS: A total of 1620 patients from June 2008 to December 2008 in our hospital undergoing general anesthesia with remifentanil and whose length of operative incision was less than 4 cm were enrolled. The incidence of postoperative hyperalgesia was investigated and recorded at the timepoints of staying at post-anesthesia care unit (PACU), 4 h and 24 h postoperation respectively. The unconditional statistical analysis of Logistic regression was used to explore such possible influencing factors as age, gender, methods of general anesthesia, operative duration, operative sites and remifentanil dose. RESULTS: The incidence of postoperative remifentanil-induced hyperalgesia was 16.1% (n = 261). The incidence of postoperative hyperalgesia was significantly increased in patients < 16 yrs (25.9%) vs ≥ 16 yrs (15.6%) (P < 0.05), males vs females (20.8% vs 13.0%, P < 0.01), operative duration > 2 h (32.7%) vs ≤ 2 h (9.9%) (P < 0.01) and remifentanil dose > 30 µg/kg (41.8%) vs ≤ 30 µg/kg (4.8%) (P < 0.01). And the incidence of limb protective action, touch and cold-induced allodynia were the two highest indicators (39.0%, 34.5%). Analysis of Logistic regression showed that ages under 16 years old, operative duration > 2 h and remifentanil dose > 30 µg/kg were relevant with hyperalgesia (all P < 0.05). CONCLUSION: Ages under 16 years old, operative duration and remifentanil dose are the risk factors for postoperative remifentanil-induced hyperalgesia. Neither methods of general anesthesia nor operative sites has any effect on the occurrence of hyperalgesia.

Sufentanil reduces emergence agitation in children receiving sevoflurane anesthesia for adenotonsillectomy compared with fentanyl.

BACKGROUND: Emergence agitation is a common problem in pediatric anesthesia, especially after sevoflurane induction and maintenance anesthesia. The purpose of this study was to investigate the effect of sufentanil to reduce emergence agitation after sevoflurane anesthesia in children undergoing adenotonsillectomy compared with fentanyl. METHODS: One hundred and five children, aged 3 - 11 years, were randomly allocated to receive normal saline (control group), sufentanil 0.2 µg/kg (S2) or fentanyl 2 µg/kg (F2) 1 minute after loss of the eyelash reflex. Anesthesia was induced and maintained with sevoflurane. Time to tracheal extubation, recovery time, Paediatric Anesthesia Emergence Delirium (PAED) scale, and emergence behavior were assessed. RESULTS: The incidence of severe agitation was significantly lower in S2 and F2 groups vs. the control group, 4/32 and 15/34 vs. 24/34 respectively, (P = 0.002, 0.009, respectively). PAED scales were significantly different among three groups (P = 0.007), and lower in the S2 and F2 groups than in the control group (P = 0.007 and P = 0.025, respectively). And the incidence of severe agitation and the PAED scale score was significantly different between the S2 and F2 groups (P = 0.007, P = 0.019, respectively). Time to tracheal extubation and recovery time were similar in all three groups. CONCLUSIONS: Administration of sufentanil at 0.2 µg/kg after induction of anesthesia reduced emergence agitation in children receiving sevoflurane anesthesia for adenotonsillectomy compared with fentanyl. This was without delaying the recovery time or causing significant hypotension.

[Effect of the new propofol target controlled infusion system in children undergoing high ligation of hernial sac].

OBJECTIVE: To discuss the effect of the new target controlled infusion (TCI) system in Chinese children undergoing minor operation and compared with TCI system with Marsh parameters. METHODS: Ninety ASA I, aged 3 - 5 yrs children undergoing elective unilateral high ligation of hernial sac under general anesthesia were randomly divided into group L (n = 45) and group M (n = 45) 2 groups. All subjects were unpremedicated. Systolic blood pressure (SBP), diastolic blood pressure (DBP), ECG, SpO2 and BIS were monitored. Patients of Group L and group M were anesthetized with propofol by Lian propofol TCI system and Marsh system respectively, combined with regional block. The target plasma concentration of TCI system was set at 6 microg/ml initially and up-regulated 1 microg/ml gradually if obvious body movement occurred while skin incision. If the target plasma concentration up to 8 microg/ml but there still had body movement, the TCI venous anesthesia was replaced by inhaled anesthesia. HR, RR, SBP, DBP and BIS were recorded in time points of baseline (T(0)), after the induction (T(1)), skin incision (T(2)), 3, 5 min after skin incision (T(3), T(4)), the end of operation (T(5)). Complications, the awakening time and the number of cases which anesthetized with different propofol plasma concentrations or inhaled anesthesia were recorded respectively as well. RESULTS: The number of cases which completed the operation under TCI plasma concentration 6 microg/ml in group L were significantly more than those in group M (P < 0.01). There were significantly different of T(1)-T(4) values of HR, RR, SBP, DBP and BIS in group M (P < 0.05), but not in group L. Compared with group L, T(2)-T(4) values of HR, RR, SBP, DBP and BIS were higher in group M (P < 0.05 or 0.01). Complications were lower in group L than those in group M. CONCLUSION: Compared with Marsh system, propofol 6 microg/ml plasma concentration with the new target controlled infusion system applied in Chinese children undergoing unilateral high ligation of hernial sac could maintain stable hemodynamics, less stress reaction and complications.