Infraclavicular block in children: Is blocking lateral or posterior cord equally successful?

Background and Aims: The most effective approach for infraclavicular brachial plexus block in adults is to target the posterior cord, usually situated posterior to axillary artery. However, we do not know if this can be extrapolated in children. Our primary objective was to compare the clinical success rate of ultrasound guided infraclavicular brachial plexus block in children with local anesthetic injection aimed at two targets. These were posterior to axillary artery (posterior cord) and lateral to axillary artery (lateral cord). The secondary objectives involved need for intraoperative rescue analgesia, evaluation of duration of analgesia, incidence of complications such as pneumothorax and arterial puncture, comparison of postoperative pain scores and fluoroscopic dye spread pattern was also observed. Material and Methods: It was a randomized, prospective pilot study. Forty children undergoing forearm and hand surgeries were randomized to two groups, in accordance with the target site of the block. Target sites of Group P (20 patients) and Group L (20 patients) were posterior and lateral to the axillary artery, i.e., posterior and lateral cord respectively. Aforesaid objectives were assessed. SPSS (Version 15.0) statistical package was used. Comparison between Group L and P was by using student's unpaired t test for age and weight. Fisher's exact probability test was applied to compare percentages between groups. Results: Blocks of both groups were equally successful. No patient required intraoperative rescue analgesia. Duration of analgesia was comparable. Both groups had no major complications and similar postoperative pain scores. Conclusions: The success rate of infraclavicular brachial plexus block by aiming at the lateral and posterior cord was similar.

Avoidance of deep anesthesia and artificial airways in 1000 neonates and infants using regional anesthesia: A retrospective observational analysis.

BACKGROUND AND AIMS: Current concerns related to the anesthetic neurotoxicity have brought a renewed interest in regional anesthesia. Regional anesthesia reduces the need for opioids and inhalational anesthetics. The immaturity of the neonatal and infant nervous system may render them more prone to neurotoxicity. We describe our technique of anesthesia, which minimizes the exposure to general anesthetics and reduces airway instrumentation because the operability is rendered by the regional block. MATERIAL AND METHODS: This was a retrospective case series of neonates and infants undergoing common surface surgeries. We describe our technique of anesthesia where regional blocks are the mainstay. We also put up the data pertaining to block effectiveness, technique, end-tidal sevoflurane concentration and complications. RESULTS: One thousand patients, including neonates and infants, received central and peripheral nerve blockade. The failure rate in upper extremity blocks 0% without complications. 86.12% were given under ultrasonography (USG) guidance and 13.89% were given with peripheral nerve stimulation. The failure rate of sciatic block single shot and continuous was 0%. 92.53% were given with USG guidance while 7.46% received sciatic with nerve stimulation technique. Failure rate of caudal epidural block was 0. 78% requiring a rescue analgesic, 1.4% had blood in the needle. Out of the caudals, 33.33% were done with USG guidance and 66.67% blocks were given with traditional techniques. Out of the 322 penile + ring blocks given by traditional method, 1 block failed requiring rescue analgesics. The mean sevoflurane concentration was 1.2 +/- 0.32. CONCLUSION: It is feasible to conduct surface surgeries in the most vulnerable population such as neonates and infants under regional anesthesia without intubation and airway instrumentation.

Does ultrasound guidance add accuracy to continuous caudal-epidural catheter placements in neonates and infants?

BACKGROUND: Caudo-lumbar and caudo-thoracic epidural anesthesia is an established technique that carries a low risk of dural puncture or spinal cord trauma in infants. Traditionally catheter advancement is based on external measurements. However, malpositioning of catheters are known to occur. We hypothesized that caudal-epidural catheters inserted under real-time ultrasound guidance may be more accurate than the accuracy of the measurements traditionally used for their placement. METHODS: We studied 25 patients, aged 2 days to 5 months, posted for abdominal or thoracic surgery, receiving general anesthesia followed by caudo-epidural continuous block. External measurement defined as the distance from the caudal space and the surgically congruent vertebral level was measured in centimeters with the back gently flexed. Subsequently, a caudo-epidural block was performed in the same position. The epidural catheter insertion was followed under real-time ultrasound guidance till the predetermined vertebral level was reached. The actual length placed under real-time ultrasound scan was defined as the actual length. The high-frequency probe was placed longitudinal and paramedian to the spine. The vertebral level was determined by identifying the lumbosacral junction in longitudinal saggital view and counting the vertebrae up from L5. The catheter length at the skin was compared with the length recorded by external measurement. RESULTS: The actual length placed under real-time ultrasound scan were consistently longer than the external distance between the caudal space and selected vertebral level. The mean values of ultrasound were higher than the mean values of external measurement with a difference of 4.28 cm. Accuracy was not affected by age or affected by the selected vertebral level in the age group we studied. CONCLUSION: We conclude that catheters placed under ultrasound guidance are more accurate than the traditional method developed before the advent of ultrasound in young infants.

Comparison of success rate of ultrasound-guided sciatic and femoral nerve block and neurostimulation in children with arthrogryposis multiplex congenita: a randomized clinical trial.

BACKGROUND AND OBJECTIVES: Arthrogryposis multiplex congenital is hallmarked with immobile joints and muscle fibrosis. The main objective of this study was to compare the success rate of ultrasound-guided sciatic and femoral nerve blocks with nerve stimulations in children diagnosed with distal arthrogryposis multiplex congenita. METHOD: Sixty children aged 8 months to 2 years posted for foot surgery were randomly assigned to group NS and group US of 30 each. Under general anesthesia, femoro-sciatic block was performed with nerve stimulator guidance in group NS and ultrasound guidance in group US. RESULTS: Group NS: 23 of 30 (76.7%) children showed ankle movement with sciatic neurostimulation. In 7 (23.6%), distal motor response could not be elicited and the block was abandoned. Out of 23 children who could be given femoral block, in 12 (52%) patients quadriceps contractions were not elicited and fascia iliaca block was given. All 23 blocks were successful. CHIPPS score at 1, 4, 6, 8, and 10 h was 1.05 ± 0.90, 1.82 ± 1.18, 3.36 ± 1.65, 2.23 ± 2.02, and 1.18 ± 1.14, respectively. Group US: In 29 of 30 patients (96.6%), sciatic nerve was visualized with ultrasonography. All 29 children received femoral block, and they were successful. The odds of success in group US were 8.9 (95% confidence interval [1.0, 77.9]) as compared with NS group. The difference in success rate was statistically significant (P = 0.026). The analgesic duration difference in the US and NS groups was a mean 7.62 ± 0.57 h in group NS and 8.60 ± 0.66 h in group US (statistically significant [P < 0.001]). CHIPPS score at 1, 4, 6, 8, and 10 h was 0.79 ± 0.96, 1.61 ± 0.92, 2.96 ± 1.04, 2.36 ± 2.54, and 1.14 ± 1.01, respectively. The difference between the CHIPPS score was not statistically significant. CONCLUSION: Ultrasonography significantly increases the success rate of sciatic and femoral block in arthrogryposis.

Echo-guided estimation of formula for paravertebral block in neonates, infants and children till 5 years.

AIMS: The aim of the study was to derive a clinically useful formula for paravertebral block for thoracic, lumbar (L1) and cervical level (C6) as per the ultrasound-guided measurements in neonates, infants and children up to 5 years of age. SETTINGS AND DESIGN: Observational study. METHODS: Seventy-five patients from 2 days to 60 months were included. Paravertebral transverse ultrasound scans at cervical (C6), thoracic (T1-12) and lumbar (L1) regions were viewed to determine the optimal insertion point and depth for performing paravertebral blocks. The lateral distance from the spinous process to the insertion point and the depth from the insertion point to the paravertebral space or reference point (point just anterior to the transverse process) were measured. STATISTICAL ANALYSIS: Data was analyzed using the SPSS (V 10.0) package. Preliminary data was collected with the actual values of paravertebral parameters and weight and age. Initially, Pearson Bivariate Correlation Coefficients were calculated between parameters and age and weight so as to predict paravertebral parameters with the help of weight and age. As there were statistically significant associations between parameters and age and weight, an attempt was made to predict parameters with the help of age and weight. Multiple regression method (forward) was applied by taking parameters as dependent variables and age and weight as independent variables. RESULTS: Age and weight correlated very well (statistically significant) with paravertebral parameters; hence, prediction (regression) equations were calculated as: Prediction (regression) equation: C6A=0.005 × wt + 0.005 × age + 1.31 C6B=0.009 × wt + 0.002 × age + 1.78 T1-12 A=0.02 × wt + 0.003 × age + 0.93 T1 to 12 B=0.03 × wt + 0.03 × age + 1.02 L1A=0.03 × wt + 0.02 × age + 0.91 L1B=0.05 × wt + 0.02 × age + 0.94 CONCLUSIONS: We could derive equations to predict the values for paravertebral blocks in centimetres at different levels in the study population.

Feasibility and efficacy of placement of continuous sciatic perineural catheters solely under ultrasound guidance in children: a descriptive study.

BACKGROUND: Placement of sciatic catheters with ultrasound and stimulating catheters is known. Literature regarding catheter placements with only ultrasound is limited. We aimed to investigate the feasibility of performing continuous sciatic nerve block exclusively with ultrasound guidance and minimal equipment. METHOD: Forty ASA 1 and 2 patients aged 8 months-10 years posted for congenital talipoequinovarus surgery were included in the study. Continuous sciatic catheters were placed under ultrasound guidance with 18- gauge Tuohy needle at the infragluteal fold. Then, 0.25% of bupivacaine 0.5 ml·kg(-1) bolus was injected followed by continuous infusion later. Half the volume of the drug was injected prior to catheter insertion to improve visibility. The sciatic nerve, needle tip and shaft, catheter tip and the drug spread were visualized. The efficacy of the block intraoperatively and postoperatively was evaluated. RESULTS: The sciatic nerve, needle shaft, and tip were well visualized in all 40 patients. The catheter tip was seen in 72.5% of patients. The effect of block was complete intraoperatively and postoperatively. Clinically significant complications were absent. CONCLUSION: We conclude that in children, continuous sciatic catheters can be accurately and efficaciously placed with minimal equipment with ultrasound alone.

Ultrasound-guided sciatic nerve block in infants and toddlers produces successful anesthesia regardless of the motor response.

BACKGROUND AND OBJECTIVES: The primary objective of this study was to assess the success rate of ultrasound-guided sciatic needle placement regardless of the motor stimulation in infants and toddlers. METHODS: Forty-five consecutive patients aged 7 months-2 years, scheduled for foot surgery, were included in this prospective, descriptive and blinded study. After induction of general anesthesia, sciatic nerve block was performed under ultrasound guidance in the subgluteal area using an insulated needle connected to a nerve stimulator, with the power off. At the precise point when it was presumed that the needle was touching the sciatic nerve, the peripheral nerve stimulator was turned on at 0.5 mA and the current was slowly decreased to 0.2 mA. Presence and location of any motor responses were observed and recorded. Statistical analysis was applied to compare the success rate in patients who did and did not exhibit a motor response to electrical stimulation. Postoperatively, block duration and analgesic consumption were recorded. RESULTS: The sciatic nerve could be distinctly visualized in 44 children, and all these blocks were successful. Only 22% patients showed any motor response to electrical stimulation. There was no significant difference in block characteristics between patients who exhibited a motor response with electrical stimulation and those who did not. CONCLUSION: Success rate of ultrasound-guided sciatic nerve block remains unaltered irrespective of motor response to neurostimulation.