Median effective dose of 0.2% ropivacaine for ultrasound-guided median nerve block in young children.

OBJECTIVE: To determine the median effective dose (ED50) and the 95% effective dose (ED95) of 0.2% ropivacaine for ultrasound-guided lower forearm median nerve block in paediatric patients. METHODS: Eligible children were American Society of Anesthesiologists (ASA) status I-II scheduled to have elective open surgery for trigger thumb repair. Patients were stratified into two age groups: 1- to 3-year-olds and 3- to 6-year-olds. The ED50 was determined by Dixon's up-and-down method. The first patient received an ultrasound-guided median nerve block by injection of 2 mL of 0.2% ropivacaine. Each subsequent patient's dose was determined by the response of the previous patient, the doses being adjusted in intervals of 0.2 mL. In addition, the 95% effective dose (ED95) was obtained using a probit regression approach. The patients' general condition, postoperative pain scores, and adverse events were recorded. RESULTS: A total of 52 children who were scheduled to undergo open surgery for trigger thumb were included in this study: 28 in the 1- to 3-year-olds group and 24 in the 3- to 6-year-olds group. The ED50 (95% confidence interval) values were 0.9 (0.44-1.36) mL in 1- to 3-year-olds and 1.4 (1.14-1.66) mL in 3- to 6-year-olds. The ED95 (95% confidence interval) values were 1.5 (0.98-1.58) mL in 1- to 3-year-olds and 1.7 (1.54-1.78) mL in 3- to 6-year-olds. No adverse events occurred. CONCLUSIONS: A single dose of ropivacaine was an effective agent for young children requiring ultrasound-guided lower forearm median nerve block in open surgery for trigger thumb. The ED50 (95% confidence interval) values were 0.9 (0.44-1.36) mL in 1- to 3-year-olds and 1.4 (1.14-1.66) mL in 3- to 6-year-olds. The ED95 (95% confidence interval) values were 1.5 (0.98-1.58) mL in 1- to 3-year-olds and 1.7 (1.54-1.78) mL in 3- to 6-year-olds.

The 90% minimum effective volume and concentration of ropivacaine for ultrasound-guided median nerve block in children aged 1-3 years: A biased-coin design up-and-down sequential allocation trial.

BACKGROUND: Median nerve block can provide excellent analgesia during open surgery for trigger thumb in children. However, no data on the 90% minimum effective volume (MEV90) and concentration (MEC90) of ropivacaine for ultrasound-guided median nerve block in pediatric patients have been reported. DESIGN: A prospective two-phase study with an up-and-down sequential allocation trial using a biased coin design. PATIENTS: Children aged 1-3 years are experiencing open surgery for trigger thumb. INTERVENTION: This study has 2 parts, one for MEV90 and subsequently studied MEC90 from the former part of the study. The MEV90 and MEC90 of ropivacaine for each subsequent patient were determined by the response of the previous patient, with the biased coin design up-and-down sequential allocation trial. The interval of -volume or concentration was -0.1 ml or 0.01%, respectively. MEASUREMENTS: The MEV90 and MEC90 of ropivacaine for ultrasound-guided median nerve block in pediatric patients, were then used to estimate the 99% minimum effective volume (MEV99) and concentration (MEC99). The patient's general condition, postoperative pain, and adverse events. MAIN RESULTS: A total of one hundred and eighteen children were enrolled for the study, and 56 and 62 patients were enrolled for the MEV90 and MEC90 studies, respectively. The MEV90 of 0.2% ropivacaine was 1.44 ml (95% CI 1.043 ml, 1.466 ml), and the MEC90 of 1.5 ml ropivacaine was 0.195% (95% CI 0.159%, 0.197%). There were no adverse events that occurred. CONCLUSION: For ultrasound-guided median nerve block in children aged 1-3 years old with trigger finger undergoing open surgery, the MEV90 of 0.2% ropivacaine is 1.44 ml (95% CI 1.043 ml, 1.466 ml), and the MEC90 of 1.5 ml of ropivacaine is 0.195% (95% CI 0.159%, 0.197%).

Cognitive function in congenital heart disease after cardiac surgery with extracorporeal circulation.

BACKGROUND: Congenital heart disease (CHD) may cause deleterious effects on cognitive function in children. This study aimed to evaluate the changes of the cognitive and academic functioning in children aged less than 4 years with serious CHD following cardiac surgery with extracorporeal circulation (ECC). METHODS: A total of 100 children, aged 0-4 years with cyanotic (35) and acyanotic (65) heart diseases who had undergone cardiac surgery with ECC, were subjected to neuropsychological and behavioral evaluation using the Gesell Developmental Schedule (GDS) before operation and at 1 week, and 1, 3 and 6 months after operation. RESULTS: The GDS scores in the first postoperative week were significantly lower than those before operation, but the scores increased gradually (P<0.01). ECC affected the GDS scores after operation, with the cyanotic children being more significantly affected than the acyanotic children. The GDS scores were negatively correlated with the age at each time point. The GDS scores were significantly lower in the cyanotic children than in the acyanotic children at 1 and 3 months postoperatively (P<0.01), but there was no significant difference at 6 months (P<0.05). CONCLUSIONS: After cardiac surgery with ECC, the younger the children who have cardiac surgery, the more significantly the GDS score increases. The ECC mainly affects the cognitive ability and academic performance in cyanotic children in one month postoperatively.

Comparison of S100B and NSE between cardiac surgery and interventional therapy for children.

This study aimed to compare the release of S100B and NSE between cardiac surgery and interventional therapy for children and to investigate whether S100B serum concentration correlates with cardiopulmonary bypass in children. For this study, 40 children with congenital heart disease were selected and assigned to two groups: group A (20 children undergoing surgical therapy) and group B (20 children undergoing interventional therapy). In group A, blood samples were drawn 10 min after the induction of anesthesia, immediately after aortic cross-clamping, immediately at the end of cardiopulmonary bypass (CPB), immediately at the end of the operation, then 6 and 24 h after the operation. In group B, blood samples were drawn 10 min after the induction of anesthesia, immediately at the end of the procedure, then 6 and 24 h after the procedure. In group A, S100B plasma levels during the perioperative period and 6 h after the operation were higher than the preoperative level (p < 0.05). The NSE plasma concentrations at the termination of CPB and postoperatively were higher than the preoperative level (p < 0.05). Significant correlation was found between the peak value of S100B at the termination of CPB and the durations of both CPB and aortic cross-clamping. In group B, the differences in S100B and NSE between the post- and preoperative levels were not statistically significant (p > 0.05). The perioperative cerebral impairment indirectly evaluated by the release of NSE and S100B protein is greater in children undergoing CPB than in children undergoing interventional therapy. The release of S100B had a strong correlation with the durations of CPB and aortic cross-clamping in children.

[Effects of Shenfu Injection on inflammatory cytokines during cardiopulmonarbypass in infants].

OBJECTIVE: To evaluate the effects of Shenfu Injection (SF) on cytokines during cardiopulmonary bypass (CPB) in infants. METHODS: Twenty-four infants with congenital heart disease, aged below three years, were randomly assigned to the control group and the SF group equally. In the SF group, 1 mL/kg of SF was given through center vein pump after center vein puncture being performed, while only normal saline was given instead in the control group. Blood sample was obtained for measurement of serum necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) concentration by ELISA, at various time points in the process, i.e. right after anesthesia induction (T1), beginning of CPB (T2), aortic off-clamping (T3), 20 min after CPB (T4), the end of CPB (T5), and 6 h (T6) and 24 h (T7) after CPB. RESULTS: The time for reverting to sinus heart rhythm and analepsia after CPB was shorter in the SF group than in the control group (P < 0.05). Serum concentration of TNF-a and IL-6 was equal in the two groups at T1; they increased significantly after CPB (P < 0.05), reached the peak value at T4 and reduced to the normal level at T7 in the control group. TNF-alpha concentration was significantly lower at T3, T4 and T5, and IL-6 concentration was lower at T4 in the SF group than that in the control group at corresponding time point (P < 0.05). CONCLUSION: SF could shorten the time for reverting to sinus heart rhythm and analepsia after CPB in infants, and suppress the inflammatory response caused by CPB.