The effects of different anesthesia techniques on free radical production after tourniquet-induced ischemia-reperfusion injury at children's age.

BACKGROUND/AIM: Reperfusion of previously ischemic tissue leads to injuries mediated by reactive oxygen species. The aim of the study was to investigate the effects of different anesthesia techniques on oxidative stress caused by tourniquet-induced ischemia-reperfusion (IR) injury during extremity operations at children's age. METHODS: The study included 45 patients American Society of Anesthesiologists (ASA) classification I or II, 8 to 17 years of age, undergoing orthopedic procedures that required bloodless limb surgery. The children were randomized into three groups of 15 patients each: general inhalational anesthesia with sevoflurane (group S), total intravenous anesthesia with propofol (group T) and regional anesthesia (group R). Venous blood samples were obtained at four time points: before peripheral nerve block and induction of general anesthesia (baseline), 1 min before tourniquet release (BTR), 5 and 20 min after tourniquet release (ATR). Postischemic reperfusion injury was estimated by measurement of concentration of malondialdehyde (MDA) in plasma and erythrocytes as well as catalase (CAT) activity. RESULTS: Plasma MDA concentration in the group S was significantly higher at 20 min ATR in comparison with the groups T and R (6.78 +/- 0.33 micromolL-1(-1) vs. 4.07 +/- 1.53 and 3.22 +/- 0.9. micromolL-1(-1), respectively). There was a significant difference in MDA concentration in erytrocythes between the groups S and T after 5 min of reperfusion (5.88 +/- 0.88 vs. 4.27 +/- 1.04 nmol/mlEr, p < 0.05). Although not statistically significant, CAT activity was slightly increased as compared to baseline in both groups S and R. In the group T, CAT activity decreased at all time points when compared with baseline, but the observed decrease was only statistically significant at BTR (34.70 +/- 9.27 vs. 39.69 +/- 12.91 UL-1, p < 0.05). CONCLUSION: Continuous propofol infusion and regional anesthesia techniques attenuate lipid peroxidation and IR injury connected with tourniquet application in pediatric extremity surgery.

[Peripheral nerve blocks in paediatric anaesthesia].

INTRODUCTION: Most children undergoing surgery can benefit from regional anaesthetic techniques, either as the sole anaesthetic regimen or, as usual in paediatric practice, in combination with general anaesthesia. The use of peripheral nerve blocks (PNBs) in paediatric anaesthesia is an effective way to decrease the side-effects and complications associated with central blocks. In spite of their many advantages, including easy performance end efficacy, peripheral nerve blocks are still underused. OBJECTIVE: This article discusses a general approach to PNBs in children and provides data concerning the practice of this regional technique in different age groups. METHODS: Data from 1,650 procedures were prospectively collected during the period from March 1, 2007 to February 29, 2008. The type of PNB, if any, as well as the patient age were noted. Our patients were divided into four groups: 0-3 years, 4-7 years, 8-12 years and 13-18 years. RESULTS: During the investigated period, PNBs as a sole technique or in anaesthetized children were performed in 7.45% of cases. Ilioinguinal/iliohypogastric nerve block and penile block were the most common (70% of all PNBs) distributed mainly among the children between 4-7 years of age (p < 0.05). In older children, extremity PNBs predominate in regard to other types of blocks. PNBs are most frequently performed under general anaesthesia (85%), so the perineural approach requires a safe technique to avoid nerve damage. CONCLUSION: The observed differences in PNB usage seem to be related to patient age and correlate with common pathology and also with technical availability of PNB performance.