A comparison between local anaesthetic dorsal nerve block and caudal bupivacaine with ketamine for paediatric circumcision

BACKGROUND: Ketamine has been shown to prolong analgesia produced by caudal local anaesthetic block and is now in common use. This study compares caudal block using bupivacaine/ketamine with dorsal nerve block of the penis. METHODS: Sixty boys undergoing elective circumcision were given either 0.5 ml x kg-1 of bupivacaine 0.15% with ketamine 0.5 mg x kg-1 (n = 30) or dorsal nerve block of the penis with bupivacaine 0.5% (n = 30) as a supplement to general anaesthesia. Postoperative pain was assessed by parents using a modified objective pain score, and the time taken to first requirement of analgesia was recorded. Motor weakness, time to first micturition, postoperative nausea and vomiting (PONV), eating habits, sleep disturbance and behaviour were also assessed. RESULTS: There was no difference between the groups in time to first requirement for analgesia or number of doses of paracetamol given in the first 24 h. Almost half the boys in the caudal group had motor weakness, and there was a significant increase in time to first micturition in that group. There was no difference between the groups in PONV, eating, sleeping or behavioural disturbance. CONCLUSIONS: Caudal anaesthesia with bupivacaine/ketamine does not confer any advantage over a dorsal nerve block with the doses used in this study. Because of the higher incidence of side-effects and technique failure in the caudal group, dorsal nerve block is perhaps the preferred technique.     

Unilateral groin surgery in children: will the addition of an ultrasound‐guided ilioinguinal nerve block enhance the duration of analgesia of a single‐shot caudal block?

Background: Inguinal hernia repair, hydrocelectomy, and orchidopexy are commonly performed surgical procedures in children. Postoperative pain control is usually provided with a single‐shot caudal block. Blockade of the ilioinguinal nerve may lead to additional analgesia. The aim of this double‐blind, randomized controlled trial was to evaluate the efficacy of an adjuvant blockade of the ilioinguinal nerve using ultrasound (US) guidance at the end of the procedure with local anesthetic vs normal saline and to explore the potential for prolongation of analgesia with decreased need for postoperative pain medication. Methods: Fifty children ages 1–6 years scheduled for unilateral inguinal hernia repair, hydrocelectomy, orchidopexy, or orchiectomy were prospectively randomized into one of two groups: Group S that received an US‐guided ilioinguinal nerve block with 0.1 ml·kg^?1 of preservative‐free normal saline and Group B that received an US‐guided nerve block with 0.1 ml·kg^?1 of 0.25% bupivacaine with 1 : 200 000 epinephrine at the conclusion of the surgery. After induction of anesthesia but prior to surgical incision, all patients received caudal anesthesia with 0.7 ml·kg^?1 of 0.125% bupivacaine with 1 : 200 000 epinephrine. Patients were observed by a blinded observer for (i) pain scores using the Children and Infants Postoperative Pain Scale, (ii) need for rescue medication in the PACU, (iii) need for oral pain medications given by the parents at home. Results: Forty‐eight patients, consisting of 46 males and two females, with a mean age of 3.98 (sd ± 1.88) were enrolled in the study. Two patients were excluded from the study because of study protocol violation and/or alteration in surgical procedure. The average pain scores reported for the entire duration spent in the recovery room for the caudal and caudal/ilioinguinal block groups were 1.92 (sd ± 1.59) and 1.18 (sd ± 1.31), respectively. The average pain score difference was 0.72 (sd ± 0.58) and was statistically significant (P < 0.05). In addition, when examined by procedure type, it was found that the difference in the average pain scores between the caudal and caudal/ilioinguinal block groups was statistically significant for the inguinal hernia repair patients (P < 0.05) but not for the other groin surgery patients (P = 0.13). For all groin surgery patients, six of the 23 patients in the caudal group and eight of the 25 patients in the caudal/ilioinguinal block group required pain rescue medications throughout their entire hospital stay or at home (P = 0.76). Overall, the caudal group received an average of 0.54 (sd ± 1.14) pain rescue medication doses, while the caudal/ilioinguinal block group received an average of 0.77 (sd ± 1.70) pain rescue medication doses; this was, however, not statistically significant (P = 0.58). Conclusions: The addition of an US‐guided ilioinguinal nerve block to a single‐shot caudal block decreases the severity of pain experienced by pediatric groin surgery patients. The decrease in pain scores were particularly pronounced in inguinal hernia repair patients.     

Regional techniques for pediatric day surgery

Regional blocks provide effective pain relief in pediatric day surgery, but local anesthetics are part of a concept that also includes nonsteroidal anti-inflammatory drugs. The choice of the regional technique is crucial to avoid unnecessary motor blockade and other side effects leading to prolonged hospital stay. For many interventions simple wound infiltration is therefore the optimal choice. For inguinal incisions, caudal anesthesia with approximately 1 mL/kg of bupivacaine 0.125% with epinephrine or ilioinguinal nerve block is widely used. Although ilioinguinal nerve block is preferable in older children, caudal anesthesia seems preferable for infants and toddlers. For penile surgery, penile block is the gold standard; the subpubic technique is described in detail. For extremity procedures, axillary brachial plexus block or intravenous regional anesthesia can be used in selected children. Copyright © 2000 by W.B. Saunders Company     

Other techniques for obstetric pain management: Caudal, paracervical, and pudendal blocks

The use of paracervical, pudendal, and caudal anesthesia in the obstetric population has declined over the past 30 years. However, each technique offers the unique advantage for regional anesthesia when central axial blockade is not possible or when obstetric anesthesia services are not available. Paracervical blockade inhibits pain arising from cervical dilation and uterine contractions; therefore, it is useful to relieve the pain of the first stage of labor or to provide anesthesia for postpartum dilation and curettage. The major limitation of this technique is the potential for fetal bradycardias after local anesthesia injection; therefore, it may be most useful when the fetus is not a consideration (eg, stillbirth in pregnancy). Pudendal nerve blockade provides anesthesia for the lower vagina and perineum, which is most commonly used during the second stage of labor. This block is useful for low-outlet, operative vaginal deliveries or for postpartum perineal trauma repairs. The caudal block provides epidural anesthesia of the sacral roots, although large local-anesthetic volumes anesthetize the thoracic and lumbar levels. Currently, the most favored technique of caudal anesthesia is a single-shot bolus of local anesthesia because it provides profound and expedient saddle block anesthesia/analgesia. Both anesthesiologists and delivering health care providers should be aware of these alternatives for their obstetric patients. Copyright © 2001 by W.B. Saunders Company     

髂腹下及髂腹股沟神经阻滞用于小儿腹

目的：探讨小儿腹股沟区手术麻醉安全便利的麻醉方法。方法：小儿腹股沟部手术40例．随机分成二组．1组20例以氯胺酮肌注后行髂腹下及髂腹股沟神经阻滞：Ⅱ组20例以氯胺酮胍注后行骶管阻滞麻醉。监测Bp、P．R．SpO2变化,及术毕清醒时间、术中不良反应。结果：平均年龄、手术时间两组无统计学意义（P〉0．05）．所有病例均较好地完成手术。两组生命体征．清醒时间无明显差异;切皮时Ⅱ组有4例出现肢体躁动;处理疝囊及牵拉精索时Ⅰ组中有4例出现肢体躁动;Ⅱ组有4例经多次穿刺成功．1例局部血舯。结论：作者认为髂腹下及髂腹股沟神经阻滞操作简单,穿刺引起的并发症及危险性少,麻醉效果与骶麻相似,可作为小儿腹股淘部手术的麻醉方法之一,特别是骶管阻滞困难时。     

Postoperative analgesia in children day surgery circumcision: Comparison of three methods

Objective: To compare three methods of postoperative analgesia in children who underwent day surgery circumcision. Methods: One hundred and eighty‐five boys who were admitted for day surgery circumcision were randomly allocated to one of three groups. Group 1 received caudal block, group 2 received dorsal penile nerve block and group 3 received a combination of rectal diclofenac and intravenous fentanyl (RD/IVFENT). Oral paracetamol was given to relieve postoperative pain; its requirement and postoperative complications were recorded. Results: There were no significant differences found among the three groups regarding post‐circumcision paracetamol requirements in the first 2 h and day of operation, and duration of analgesia. There was no increased wound bleeding and vomiting seen for group 3. Conclusion: RD/IVFENT is a useful alternative to caudal block and dorsal penile nerve block for providing post‐circumcision pain relief. Also, it is easier to administer and appears safe.     

Pubic tubercle side approach to the obturator nerve block

BACKGROUND: The authors describe the pubic tubercle side approach of the obturator nerve block for the management of adductor muscle constriction associated with the transurethral resection of the lateral wall bladder tumor. METHODS: The pubic tubercle side approach of the obturator nerve block was performed by a inserting needle at the midpoint of the femoral artery and the pubic tubercle. After the needle encountered the superior ramus of pubis, the needle was redirected vertical or slightly caudal, passeing the vicinity of the inferior margin of the superior ramus of pubis, and then advanced to the trunk of the obturator nerve. The obturator nerve was identified by its response to nerve stimulation. The pubic tubercle side approach using more than 5 ml of 1.0% lidocaine was performed by a single injection until there was no response to nerve stimulation. On the other hand, by the traditional approach to the obturator nerve block, after the initial local anesthetic injection the needle was redirected lateral and slightly caudal. If the response to nerve stimulation was still elicited, more local anesthetic was administered. RESULTS: Evaluation of the efficacy of the pubic tubercle side approach was performed in-terms of quantity of the local anesthetic used and the success rate. In comparison with the traditional approach, a smaller dose of local anesthetic was used in spite of the higher success rate. CONCLUSIONS: The pubic tubercle side approach of the obturator nerve was useful and without complications in comparison with the traditional approach.     

Techniques of epidural block

Epidural blocks are used for relief of chronic pain, labour pain and postoperative pain as well as for surgical anaesthesia. The effect can be targeted at the insertion level which can be from cervical spine level all the way to the sacral hiatus in the case of a caudal epidural block. Catheter insertion means doses can be repeated and the effect maintained. This contrasts with the typical single-shot spinal/subarachnoid injection primarily used for surgical anaesthesia. Specifically avoiding dural puncture also contrasts with the spinal’s simple endpoint of detecting CSF. Accurate epidural needle insertion is therefore technically more difficult. The variety of methods available to identify if the needle tip is in the epidural space highlights this much less certain endpoint. With epidural injections, drug solutions need to physically spread to access each intended nerve root. This makes epidurals less reliable than spinals, where simply depositing the solution in the CSF rapidly enables it to bathe all the nerve roots encountered. Serious risks such as direct damage to nerve tissue, infection and epidural haematoma are shared with spinal anaesthesia but may be more likely with epidural techniques. Epidural needles are wider bore and more likely to damage tissue and vessels. They are sometimes directed close to the spinal cord itself. In-dwelling catheters can move and traumatize vessels and act as a focus for infection. Despite these potential drawbacks, careful selection, skilled placement and management mean patients can safely derive the intended benefits and epidurals and caudal blocks continue to be popular.     

Techniques of epidural block

Epidural blocks are used for relief of chronic pain, labour pain and postoperative pain as well as for surgical anaesthesia. Effect can be targeted at the insertion level which can be from cervical spine level all the way to the sacral hiatus in the case of a caudal epidural block. Catheter insertion means doses can be repeated and the effect maintained. This contrasts with the typical single-shot spinal/subarachnoid injection primarily used for surgical anaesthesia. Specifically avoiding dural puncture also contrasts with the spinal's simple endpoint of detecting CSF. Accurate epidural needle insertion is therefore technically more difficult. The variety of methods available to identify if the needle tip is in the epidural space highlights this much less certain endpoint. With epidural injections, drug solutions need to physically spread to access each intended nerve root. This makes epidurals less reliable than spinals, where simply depositing the solution in the CSF rapidly enables it to bathe all the nerve roots encountered. Serious risks such as direct damage to nerve tissue, infection and epidural haematoma are shared with spinal anaesthesia but may be more likely with epidural techniques. Epidural needles are wider bore and more likely to damage tissue and vessels. They are sometimes directed close to the spinal cord itself. In-dwelling catheters can move and traumatize vessels and act as a focus for infection. Despite these potential drawbacks, careful selection, skilled placement and management mean patients can safely derive the intended benefits and epidurals and caudal blocks continue to be popular.     

Intérêt de l’échographie en ALR pédiatrique

The use of ultrasonographic guidance for regional anaesthesia has known recently a big interest in children in recent years. The linear ultrasound probes with a 25 mm active surface area (or probes with 38 mm active surface area in older children), with high sound frequencies in the range 8–14 MHz, allow a good compromise between excellent resolution for superficial structure and good penetration depths. In children, the easiest ultrasound guided blocks are axillar blocks, femoral blocks, fascia iliaca compartment blocks, ilio-inguinal blocks and para-umbilical blocks, caudal blocks. They permit a safe and easy learning curve of these techniques. The main advantage of ultrasound guided regional anaesthesia is the visualization of different anatomical structures and the approximate localization of the tip of needle. The other advantages for ultrasound guided peripheral nerve blocks in children are: faster onset time of sensory and motor block, longer duration of sensory blockade, increase of blockade quality and reduction of local anesthetic injection. The use of ultrasonographic guidance for central block allows to visualize different structures as well as spine and his content. Spinous process, ligament flavum, dura mater, conus medullaris and cerebrospinal fluid are identifiable, and give some information on spine, epidural space and the depth between epidural space and skin. At last, in caudal block, ultrasounds permit to evaluate the anatomy of caudal epidural space, especially the relation of the sacral hiatus to the dural sac and the search of occult spinal dysraphism. Benefit of this technique is the visualization of targeted nerves or spaces and the spread of injected local anaesthetic.     

Effect of ilioinguinal nerve block on the catecholamine plasma levels in orchidopexy: comparison with caudal epidural block

BACKGROUND: Both caudal epidural and ilioinguinal/iliohypogastric nerve blocks have been used to provide effective intra- and postoperative analgesia. Stress response hormone levels can be used as an objective method to assess the analgesic efficacy of the anaesthetic techniques used in infraumbilical surgery in children. In this study, we compared catecholamine blood levels in children undergoing these two different supplementary analgesic/anaesthetic techniques. METHODS: Thirty male paediatric patients undergoing orchidopexy, ASA I, received inhalation general anaesthesia, and were randomly allocated to one of two groups: a caudal group (n = 15) and an ilioinguinal/iliohypogastric nerve block group (n = 15). Plasma epinephrine and norepinephrine concentrations were measured at the induction time, at the end of surgery, and in the postanaesthesia care unit. Postoperative pain score was also assessed in the postanaesthesia care unit. Results: In both groups, there was a substantial decrease in the catecholamine blood levels; however, there were significantly higher levels of epinephrine in the ilioinguinal group at the end of surgery (P = 0.008) and in the recovery room (P = 0.02) and a significant higher level of norpinephrine in the recovery room (P = 0.008). CONCLUSIONS: The result of this study revealed that caudal epidural block was more effective than ilioinguinal block in suppressing the stress response as reflected in epinephrine and norepinephrine blood levels in orchidopexy patients.     

Paediatric regional anaesthesia--what makes a difference?

Regional anaesthetic techniques are useful for providing post-operative pain control for ambulatory surgery in children. This chapter focuses on unique features of paediatric anatomy and physiology that allow successful performance of these techniques. An overview of the effective use of long-acting local anaesthetics in children is presented. Combinations of local anaesthetics and adjunct medications that prolong caudal blockade, the most commonly performed paediatric block, are reviewed, with a goal of providing prolonged analgesia with minimal side-effects. An overview of the use of peripheral nerve blockade and specific recommendations for the use of these blocks in children is also presented.     

Caudal anaesthesia as a treatment for penile ischaemia following circumcision

We report an ischaemic penile glans following circumcision and a dorsal penile nerve block in a 9-year-old boy. Ischaemia of the glans penis is a rare complication associated independently with both circumcision and dorsal penile nerve blocks. There are a number of pathophysiological mechanisms of this ischaemia and its management is varied and not well recorded. We report the successful management of this complication using a caudal epidural block and also discuss technical aspects of penile nerve blocks.     

Confirmation of caudal needle placement using nerve stimulation.

BACKGROUND: The study was designed to examine a new method of confirming proper caudal needle placement using nerve stimulation. METHODS: Thirty-two pediatric patients were studied. A 22-gauge insulated needle was inserted into the caudal canal via the sacral notch until a "pop" was felt. The needle placement was classified as correct or incorrect depending upon the presence or absence of anal sphincter contraction (S2-S4) to electrical simulation (1 to 10 mA). RESULTS: Three patients were excluded, two because they inadvertently received neuromuscular blockers and one because the patient's anatomy precluded any attempt at a caudal block. The sensitivity and specificity of the test were both 100% in predicting clinical outcomes of the caudal block. Six patients had a negative stimulation test after the first attempt to place the needle. Four of these went on to receive a second attempt of needle insertion after a subcutaneous bulge or resistance to local anesthetic injection were observed. Following needle reinsertion, positive stimulation tests were elicited. These patients received the local anesthetic injection with ease and had good analgesia postoperatively. No attempt was made to reinsert the needle in the remaining two patients with a negative stimulation test, as they did not show subcutaneous bulge or resistance upon injection. These patients had poor analgesia postoperatively. The positive predictive value of the test was greater than the presence of a "pop" alone (P < 0.05) but not significantly different (P = 0.492) over the presence of "pop" and easy injection. CONCLUSION: This test may be used as a teaching and adjuvant tool in performing caudal block.     

Ultrasound-guided sciatic nerve block

Theoretically, sciatic nerve block can be used alone or in combination with lumbar plexus block or femoral nerve block for anesthesia and/or analgesia of lower limb surgery. However, clinical use of sciatic nerve block was limited by technical difficulties in performing the block since techniques used relies only on surface anatomical landmarks. Recent advances in ultrasound technology allow direct visualization of nerves and other surrounding structures and have increased the interest in performing many kinds of peripheral nerve blocks including sciatic nerve block. Preliminary data suggest that ultrasound-guided technique can help perform the sciatic nerve block more reliably and safely. In this article we describe the anatomy of the sciatic nerve, sonographic features, and technique of three major approaches including subgluteal, anterior, and popliteal approaches. The use of this technique for postoperative analgesia is also discussed.     

Plasma bupivacaine concentrations during caudal analgesia and ilioinguinal-iliohypogastric nerve block in children

Plasma bupivacaine concentrations were measured in 27 children aged 3-7 years who received one of two analgesic regimens for herniotomy or orchidopexy. Analgesia was provided either by caudal epidural bupivacaine 0.2% 2 mg/kg (n = 14) or by ilioinguinal-iliohypogastric nerve block with bupivacaine 0.5% 1.25 mg/kg (n = 13). Mean (SD) peak venous bupivacaine concentrations were 0.57 (0.17) microgram/ml and 0.79 (0.38) microgram/ml respectively. Time to peak plasma concentrations were 29.6 (7.9) and 22.3 (10.9) minutes respectively. These concentrations are well below the potentially toxic level of 4.0 micrograms/ml, but suggest that uptake of bupivacaine is more rapid after ilioinguinal-iliohypogastric nerve block than during caudal analgesia.     

Sonographic visualization and ultrasound-guided block of the third occipital nerve: prospective for a new method to diagnose C2-C3 zygapophysial joint pain

BACKGROUND: Chronic neck pain after whiplash injury is caused by cervical zygapophysial joints in 50% of patients. Diagnostic blocks of nerves supplying the joints are performed using fluoroscopy. The authors' hypothesis was that the third occipital nerve can be visualized and blocked with use of an ultrasound-guided technique. METHODS: In 14 volunteers, the authors placed a needle ultrasound-guided to the third occipital nerve on both sides of the neck. They punctured caudal and perpendicular to the 14-MHz transducer. In 11 volunteers, 0.9 ml of either local anesthetic or normal saline was applied in a randomized, double-blind, crossover manner. Anesthesia was controlled in the corresponding skin area by pinprick and cold testing. The position of the needle was controlled by fluoroscopy. RESULTS: The third occipital nerve could be visualized in all subjects and showed a median diameter of 2.0 mm. Anesthesia was missing after local anesthetic in only one case. There was neither anesthesia nor hyposensitivity after any of the saline injections. The C2-C3 joint, in a transversal plane visualized as a convex density, was identified correctly by ultrasound in 27 of 28 cases, and 23 needles were placed correctly into the target zone. CONCLUSIONS: The third occipital nerve can be visualized and blocked with use of an ultrasound-guided technique. The needles were positioned accurately in 82% of cases as confirmed by fluoroscopy; the nerve was blocked in 90% of cases. Because ultrasound is the only available technique today to visualize this nerve, it seems to be a promising new method for block guidance instead of fluoroscopy.     

Information and consent sheet of caudal block in the University of Tokyo Hospital

Caudal block with a local anesthetic through the hiatus sacralis has been performed in patients with chronic low back pain, lower limb pain, anal pain, and pelvic pain due to spinal canal stenosis, lumbar disc herniation, lumbar spondylolisthesis, postherpetic neuralgia, peripheral vascular disease, complex regional pain syndrome and so on. We prepar- ed an information and consent sheet on caudal block in The University of Tokyo Hospital. In the information sheet, we included disease, purpose, methods, outcome, accidental complications of caudal block, other treatments, progress on unperformed case, questions and answers, influence of rejection, and doctor's name. We experienced some cases of boring pain, deterioration of low back pain and lower limb pain, headache, nausea, hypertension, hypotension, and tachycardia as accidental complications of caudal block. In describing some accidental complications, we included boring pain, high intracranial pressure, dural puncture, nerve injury, infection, hemorrhage, embolism, allergy, and heart, lung, brain, liver, and kidney failures. Further, we could refer to the accidental complications of epidural block. However, the rate of each accidental complication has not been known in detail. We should survey the outcome and accidental complication of caudal block prospectively in multiple facilities and provide the patients with useful information.     

Nerve blocks in palliative care

Although between 85% and 90% of patients with advanced cancer can have their pain well controlled with the use of analgesic drugs and adjuvants, there are some patients who will benefit from an interventional procedure. This includes a variety of nerve blocks and also some neurosurgical procedures. Approximately 8-10% of patients may benefit from a peripheral nerve block and around 2% from a central neuraxial block. The most common indication is because opioid dose escalation is limited by signs of opioid toxicity but some patients will benefit from one component of their pain being relieved by a simple peripheral block. Most patients about to undergo these procedures are already taking high doses of opiods and obtaining valid consent may pose problems. The use of peripheral nerve blocks, epidural and intrathecal infusions, and plexus blocks is discussed.     

Comparison of anesthetic solutions used in lumbar and caudal peridural anesthesia

Clinical observations on peridural anesthesia were made in 466 patients. The spread of various concentrations of anesthetics injected into the lumbar and caudal peridural space were followed by plotting analgesia-time profiles. Onset of anesthesia and the volume required to provide one dermatome of anesthesia varied little among different anesthetics given in different concentrations. The sequence of appearance of analgesia was also similar, with longer times being required to block larger roots. Quality of anesthesia was judged by the penetration of anesthestic solutions into the largest spinal nerve root (S1); rate of penetration depended on the type of drug and concentration. No drug concentration combination included all the ideal characteristics for block: minimal mass of anesthetic, maximum spread, long duration (minutes of anesthesia per milligram of drugs per segment), low incidence of failure, and fast stabilization time. However, depending on the surgical needs and the characteristics of the patients, some drugs and concentrations may be preferred. Stabilization and onset were slower and drug requirements larger for caudal than for lumbar peridural anesthesia.