The Effects of Clonidine on Postoperative Analgesia After Peripheral Nerve Blockade in Children

Ultrasound-guided sciatic popliteal block performed at the Emergency Department in a patient with a scorpion bite and severe pain

We report the case of a paediatric patient who presented at the Emergency Department with severe pain in the right lower extremity caused by a scorpion sting. Analgesics were ineffective, so we decided to perform an ultrasound-guided popliteal block, which provided complete analgesia and allowed the patient to be followed up in the outpatient department, with no adverse effects. The sting of the species of scorpion found in Spain is not dangerous to human life; however, it causes self-limiting localised pain that lasts for 24-48h, and can be severe. The first-line treatment is effective analgesia. Regional anaesthesia techniques are useful in the control of acute pain, and are an example of effective collaboration between the Anaesthesiology and Emergency services.

The addition of clonidine to ropivacaine in rectus sheath nerve blocks for pediatric patients undergoing laparoscopic appendectomy: A double blinded randomized prospective study

STUDY OBJECTIVE

The primary goal of this study was to determine if the addition of clonidine to ropivacaine prolonged periumbilical numbness compared to ropivacaine alone in pediatric patients receiving ultrasound guided rectus sheath nerve blocks for laparoscopic appendectomy. The secondary goals were to evaluate differences in perioperative pain scores, analgesic consumption, sedation, anxiolysis, and hemodynamic effects from clonidine.

DESIGN

This was a single center, randomized, double-blinded prospective study.

SETTING

This study was conducted within the pediatric operating rooms at the Children's Hospital of Pittsburgh, a large university-based academic medical center.

PATIENTS

Fifty pediatric patients (ages 10-17 years old) without pre-existing cognitive impairment, developmental delay or chronic pain undergoing laparoscopic appendectomy during weekday hours were enrolled and randomized to control versus intervention groups.

INTERVENTION

Ultrasound guided rectus sheath nerve block injections were performed at the beginning of surgery with either ropivacaine 0.5% plus normal saline or ropivacaine 0.5% plus clonidine (2 mcg/kg, maximum of 100 mcg).

MEASUREMENTS

The duration of periumbilical numbness, Numeric Pain Rating Scale scores, University of Michigan Sedation Scale, State-Trait Anxiety Inventory for Children, analgesic consumption, heart rate, blood pressure, and mean arterial pressures, were recorded for each patient at several time points in the perioperative setting.

MAIN RESULTS

There were no significant differences in demographic characteristics between groups. The median duration of periumbilical numbness did not significantly differ between the ropivacaine only and the ropivacaine plus clonidine groups 540.0 minutes [360.0 -1015.0] (median [interquartile range (IQR)]) versus 823.5 minutes [509.5- 1080.0], p = 0.451. There were no significant differences in perioperative analgesic consumption, pain and anxiety scores, PACU sedation, or hemodynamic instability.

CONCLUSIONS

The addition of clonidine did not significantly prolong rectus sheath nerve block duration and was well tolerated in pediatric patients. Perioperative analgesia, hemodynamics, anxiety, and PACU sedation did not differ between groups.

TRIAL REGISTRATION

Clinical Trials NCT02439281.

Anesthetic Success Using Nitrous Oxide and a Combination of Lidocaine/Clonidine for the Inferior Alveolar Nerve Block and the Effects on Blood Pressure and Pulse in Patients with Symptomatic Irreversible Pulpitis: A Prospective, Randomized, Double-blind Study

INTRODUCTION

The pulpal anesthetic success rates for an inferior alveolar nerve block (IANB) alone in patients presenting with symptomatic irreversible pulpitis are less than adequate. Nitrous oxide and clonidine have shown increases in IANB success when administered individually, but their success has not been evaluated when used together. The purpose of this prospective, randomized, double-blind study was to determine the effect of nitrous oxide/oxygen plus an IANB using lidocaine/clonidine on the success of the IANB in patients with symptomatic irreversible pulpitis and to evaluate the effect of clonidine on blood pressure and pulse.

METHODS

Sixty-two emergency patients experiencing moderate to severe pain and a diagnosis of symptomatic irreversible pulpitis were enrolled. Subjects were randomly divided into 2 groups and received nitrous oxide/oxygen and an IANB using 2% lidocaine with either 27 μg clonidine or 18 μg epinephrine as vasoconstrictors. Blood pressure and pulse were recorded before and during the emergency endodontic treatment. Anesthetic success was defined as no or mild pain upon access and instrumentation of the canals.

RESULTS

The pulpal anesthetic success rate in both treatments was 58%, with no significant difference between the groups. There was no statistically significant difference in pulse or systolic blood pressure with the use of clonidine compared with epinephrine. Diastolic blood pressure was significant.

CONCLUSIONS

The use of nitrous/oxide plus the addition of lidocaine/clonidine for the IANB in teeth with symptomatic irreversible pulpitis resulted in no statistically significant difference in anesthetic success of the IANB. There were no statistically significant differences in pulse or systolic blood pressure with the use of clonidine compared with epinephrine; diastolic blood pressure was significant.

Clonidine as an Adjuvant to Bupivacaine for Suprazygomatic Maxillary Nerve Blocks in Cleft lip and Palate Repair: A Randomized, Prospective, Double-Blind Study

OBJECTIVES

Does clonidine, as adjuvant to bupivacaine for suprazygomatic maxillary nerve blocks, reduce emergence agitation in patients undergoing cleft lip and cleft palate surgery?

DESIGN

Randomized, controlled, and double-blind study.

SETTING

Guwahati Comprehensive Cleft Care Center, Guwahati (Assam, India).

PARTICIPANTS

A total of 124 patients; with a median age of 5 years in the clonidine group (CLG) and 7 years in the control group (CG), who underwent cleft lip or cleft palate surgery were included. Exclusion criteria included lack of consent from patients or their guardians, allergy to local anesthetics, coagulation disorders, local infection at the puncture site before performing the block, and language difficulties or cognitive disorders.

INTERVENTIONS

Patients were randomized into 2 groups to receive bilateral suprazygomatic maxillary nerve blocks with either a bupivacaine/clonidine mixture for the CLG or bupivacaine alone in the CG.

MAIN OUTCOME MEASURE

The primary end point was the incidence of emergence agitation.

RESULTS

There was a statistically significant difference in the incidence of emergence agitation (30.2% in the CG compared to 15.2% in the CLG; difference of incidences: 15%, 95% CI: 0.1-30.1). The percentage of patients requiring intraoperative Fentanyl was lower in the CLG (10.6% compared to 26.4%; difference of incidences: 15.8%, 95% CI: 1.8-29). No other differences were observed. Further research in a more typically aged children population undergoing cleft surgery is needed.

CONCLUSIONS

The use of clonidine as an adjuvant to bupivacaine in maxillary nerve block reduces the incidence of emergence agitation and intraoperative opioid consumption without hemodynamic or sedative side effects in patients undergoing cleft lip and palate surgery.

Trends in Pediatric Pain: Thinking Beyond Opioids

Trends in pediatric pain management are moving toward thinking beyond opioids. Regional anesthetic techniques, such as quadratus lumborum and erector spinae plane blocks, demonstrate efficacy and safety in pediatric populations. Extremity blocks with motor-sparing characteristics also are used. Adjuvants may be added to pediatric peripheral nerve blocks to increase duration of action and improve block efficacy. For medical management, pediatric pain management frequently uses nonopioid medications. These opioid-sparing medications and regional techniques are used to facilitate enhanced recovery after surgery in pediatric surgical patients. Virtual reality is a field where technology can aid in managing acute pain in pediatric patients.

The Effect of Gabapentin on Postoperative Pain of Orthopedic Surgery of Lower Limb by Sciatic and Femoral Blockage in Children: A Clinical Trial

Background

There are meta-analyzes in adults demonstrating the benefits of using gabapentin to improve postoperative pain in orthopedic surgeries. In pediatrics, it has never been studied.

Objectives

The aim of this study was to evaluate the use of gabapentin 10 mg/kg, orally, in postoperative analgesia, hemodynamic stability and its pre/postoperative anxiolytic effect in children subjected to unilateral inferior limb surgery.

Methods

We performed a double-blinded, randomized study. 84 patients in Albert Sabin Children's Hospital were selected for elective surgery that were divided into 2 groups: gabapentin group, who received gabapentin 1 to 2 hours before the procedure and the control group. Both groups were submitted to the same general anesthesia protocol with 0.125% bupivacaine femoral and sciatic block. Patients received scheduled dipyrone and morphine was used as the rescue analgesic up to 2/2 h. Postoperative pain was assessed using a scale appropriate for age (CRIES, CHIPPS or Wong-Baker face scale). We registered hemodynamic parameters, analgesic consumption and pre/postoperative anxiolytics.

Results

A decrease in pain intensity in the 4th and 8th postoperative hours was observed in gabapentin group, both groups had the same opioid consumption. Children in the gabapentin group had an odds ratio of 25.6 for preoperative sedation and gabapentin promoted reduction of postoperative agitation. During orotracheal intubation the gabapentin group exhibited attenuation of the hemodynamic response.

Conclusions

Gabapentin was superior to placebo in reducing postoperative pain. Children who received gabapentin were more sedated in the operating room, less agitated in the postoperative period and the autonomic response to intubation was reduced.

Efficacy of Clonidine as an Additive on the Duration of Action of Brachial Plexus Block Performed Under Ultrasound and Nerve Locator Guidance: A Prospective Randomized Study

Background

Clonidine, an alpha₂ agonist, when added to local anesthetics in different regional and neuraxial blocks reduces the onset time, improves the efficacy, and increases the duration of postoperative analgesia.

Aims

This study evaluated the effect of bupivacaine clonidine combination in ultrasound and nerve locator-guided supraclavicular brachial plexus block for upper limb surgeries.

Settings and Design

This was a prospective, randomized, controlled, double-blind study carried out in a tertiary care center in South India on 50 patients with American Society of Anesthesiologists (ASA) physical status classes I and II undergoing elective upper limb surgery under supraclavicular brachial plexus block.

Materials and Methods

Eligible participants were randomized equally to either Group B who received 20 ml of bupivacaine and 7 mL of 2% lignocaine or Group C who received 20 ml of bupivacaine, 7 ml of 2% lignocaine, and 100 μg of clonidine.

Statistical Analysis

Continuous outcome variables were tested for statistical significance using Student's t-test, and Mann-Whitney U-test was used for outcomes that were nonnormally distributed. Categorical variables were compared using Fisher's exact test. P <0.05 was considered as statistically significant.

Results

The onset of sensory and motor blockade was significantly faster (P < 0.05) in Group C compared to Group B. The duration of sensory and motor block and the duration of analgesia were significantly longer in Group C (P < 0.001). The sedation in Group C patients was significantly more (P < 0.05) when compared to Group B, but none of the sedation scores exceeded 3 on the Ramsay sedation score. Hemodynamic parameters did not differ between groups (P > 0.05).

Conclusion

The inclusion of 100 μg of clonidine with bupivacaine in ultrasound-guided supraclavicular brachial plexus blocks prolongs both sensory and motor blockade. It also provides significant postoperative analgesia and mild sedation which is beneficial in the immediate stressful postoperative period.

Pediatric Ambulatory Continuous Peripheral Nerve Blocks

Despite the widespread use of ambulatory continuous peripheral nerve blocks in adults, its use in children has been sporadic. Indications for the use of ambulatory continuous peripheral nerve block in children involve orthopedic procedure, where significant pain is anticipated beyond 24 hours. Techniques to place the perineural catheters in children are similar to that used in adults. The incidence of serious side effects in pediatric ambulatory continuous peripheral nerve block is extremely rare. When this is combined with the potential to increase patient and family satisfaction and decrease opioid-related side effects, ambulatory continuous peripheral nerve block become a compelling choice.

Preemptive Oral Clonidine Provides Better Sedation Than Intravenous Midazolam in Brachial Plexus Nerve Blocks

Background

Preemptive analgesia is the blocking of pain perception afferent pathways before noxious painful stimuli. Clonidine is an alpha agonist drug that is partially selective for α-2 adrenoreceptors. Clonidine is used as anti-anxiety medication and an, analgesic, and it prolongs the duration of the block in the brachial plexus block.

Objectives

To compare the effect of preemptive clonidine with midazolam on intraoperative sedation, duration of block, and postoperative pain scores.

Patients and Methods

In a randomized clinical trial, 80 patients with orthopedic fractures of an upper extremity who underwent supraclavicular nerve block were randomly assigned to receive 0.2 mg oral clonidine or 2 mg oral midazolam. Intraoperative sedation was measured at one hour after the start of urgery and again in the PACU (Post-Anesthesia Care Unit) using the Ramsay scale. The duration of sensory blockade was measured. Postoperative pain scores were measured using the VAS (Visual Analogue Scale) after entrance to recovery up to 2 hours.

Results

The percentages of patients in the calm and sedated scale were significantly higher in clonidine group (35 and 42.5%, respectively), compared to the midazolam group (17.5 and 17.5%, respectively) (P = 0.042, 0.029; respectively). Those administered fentanyl in the clonidine group 105 ± 30.8 was significantly lower than that for the midazolam group 165 ± 34.5 (P = 0.0018). The percentages of patients in the calm scale were significantly higher in the clonidine group (52.5), compared to the midazolam group (17.5) (P = 0.001) in the post-operative period. VAS scores were significantly lower at one (P = 0.01) and two hours (P = 0.001) after operation in the clonidine group, compared to the midazolam group.

Conclusions

Preemptive clonidine has many marvelous advantages over midazolam, including better sedation inside the operating room and then in the post-operative care unit, lower fentanyl doses are required during surgery, more stable heart rate and blood pressure are observed during the procedure, and patients report lower post-operative pain scores.

Alpha-2 adrenoceptor agonists as adjuncts to peripheral nerve blocks in children: a meta-analysis

BACKGROUND

Adult meta-analyses have verified that adjunct use of alpha-2 adrenoceptor agonists (A2AA) together with local anesthetics (LA) will prolong the duration of peripheral nerve blocks. The standard use of A2AAs for peripheral nerve blockade has recently been recommended also in children, but the evidence base in support of this suggestion has to date been equivocal. The purpose of this meta-analysis was to produce evidence-based data regarding the effect in children.

METHODS

Following a thorough literature search, five randomized controlled trials were included in a meta-analysis. Raw data from all studies were gathered and aggregated into patients randomized to receive plain LA (Group PLA) or LA mixed with either adjunct clonidine or dexmedetomidine (Group ADJ). The main outcome parameter was block duration (time to first administration of supplemental analgesic based on predetermined pain scores) analyzed by survival statistics. The total number of supplemental analgesic doses during the first 24 postoperative hours and serious side effects were included as secondary outcomes.

RESULTS

Pooling of the study data generated 141 patients in Group PLA and 142 patients in Group ADJ (overall n = 283; age: 0.8-13 years; weight 8-47 kg). Block duration was significantly prolonged (9.75 h vs 3.75 h) compared to the use of plain LA. Survival statistics verified a beneficial effect of using adjunct A2AAs [the log rank (Mantel-Cox) test (P = 0.0078), Gehan-Breslow-Wilcoxon test (P = 0.0027), and hazard ratio (1.653; 95% CI: 1.142 to 2.395)]. The number of patients that needed ≥ 2 doses of supplemental analgesics was higher in Group PLA (n = 19) compared to Group ADJ (n = 6) (P = 0.0088). No serious side effects were reported.

CONCLUSION

This meta-analysis provides evidence-based support for the use of adjunct alpha-2 adrenoceptor agonists when performing peripheral nerve blocks in children.

Comparison of different routes of administration of clonidine for analgesia following anterior cruciate ligament repair

Background and Aims:

A high percentage of patients undergoing arthroscopic repairs on day care basis complain of inadequate postoperative pain relief. Clonidine was evaluated for the best route as an adjuvant in regional anesthesia in anterior cruciate ligament (ACL) repair to prolong analgesia.

Material and Methods:

A prospective randomized double-blinded study was planned in a tertiary care hospital in North India in which 85 American Society of Anesthesiologists I and II patients undergoing ACL repair were enrolled. All groups received 0.5% hyperbaric bupivacaine intrathecally as in control group C. Group IT received intrathecal 1 μg/kg of clonidine along with hyperbaric bupivacaine, group IA received 0.25% bupivacaine and 1 μg/kg clonidine intra-articularly, and group NB received 0.25% bupivacaine and 1 μg/kg clonidine in femoro-sciatic nerve block (FSNB). Postoperative pain free interval and block characteristics were the primary outcomes studied.

Results:

Pain-free duration was 546.90 (±93.66) min in group NB (P < 0.001) in comparison to 234.90 (±20.99), 367.80 (±47.40) and 172.20 (±54.82) min in groups IA, IT and C, respectively. Sensory block and motor blockade in NB were 474.90 (±43.80) and 267.40 (±34.59) min, respectively, and were significantly prolonged (P > 0.001) in comparison to other groups. The mean rescue analgesic requirement and cumulative frequency of rescue analgesia were least in group NB, followed by groups IT, IA and C.

Conclusion:

Clonidine is safe and effective adjuvant with bupivacaine in prolonging analgesia through various routes employed for post knee surgery pain. The maximum prolongation of analgesia is achieved through FSNB with a risk of prolonging postanesthesia care unit stay.

Regional anesthesia for pediatric knee surgery: a review of the indications, procedures, outcomes, safety, and challenges

The indications for surgery on the knee in children and adolescents share some similarity to adult practice in that there are an increasing number of sports-related injuries requiring surgical repair. In addition, there are some unique age-related conditions or congenital abnormalities that may present as indications for orthopedic intervention at the level of the knee. The efficacy and safety of peripheral nerve blocks (PNBs) for postoperative analgesia following orthopedic surgery has been well established in adults. Recent studies have also demonstrated earlier functional recovery after surgery in patients who received PNBs. In children, PNB is gaining popularity, and increasing data are emerging to demonstrate the feasibility, efficacy, and safety in this population. In this paper, we will review some of the most common indications for surgery involving the knee in children and the anatomy of knee, associated dermatomal and osteotomal innervation, and the PNBs most commonly used to produce analgesia at the level of the knee. We will review the evidence in support of regional anesthesia in children in terms of both the quality conferred to the immediate postoperative care and the role of continuous PNBs in maintaining effective analgesia following discharge. Also we will discuss some of the subtle challenges in utilizing regional anesthesia in the pediatric patient including the use of general anesthesia when performing regional anesthesia and the issue of monitoring for compartment syndrome. Finally, we will offer some thoughts about areas of practice that are in need of further investigation.

Clonidine as an adjuvant to ropivacaine-induced supraclavicular brachial plexus block for upper limb surgeries

Background and Aims:

Ropivacaine is a new amide, long acting, pure S-enantiomer, local anesthetic, with differential blocking effect. The addition of clonidine to local anesthetic improves the quality of peripheral nerve blocks. This study was conducted to evaluate the effect of clonidine on characteristics of ropivacaine-induced supraclavicular brachial plexus block.

Material and Methods:

A total of 60 adult patients were randomly recruited to two groups of 30 each: Group I: 30 ml 0.75% ropivacaine + 1 ml normal saline. Group II: 30 ml 0.75% ropivacaine + 1 mcg/kg clonidine diluted to 1 ml with normal saline.

Results:

The onset of sensorimotor block was earlier in Group II (4.36 ± 0.81 min for sensory block and 9.83 ± 1.12 min for motor block) than in Group I (4.84 ± 0.65 min for sensory block and 10.85 ± 0.79 min for motor block). The duration of both sensory and motor block were significantly prolonged by clonidine (P < 0.001). The duration of analgesia was also prolonged in patients receiving clonidine (613.10 ± 51.797 min vs. 878.33 ± 89.955 min). Although incidence of hypotension and bradycardia was higher in Group II when compared to Group I, it was not clinically significant.

Conclusions:

Ropivacaine 0.75% is well-tolerated and provides effective surgical anesthesia as well as relief of postoperative pain. Clonidine as an adjuvant to ropivacaine significantly enhances the quality of supraclavicular brachial plexus block by faster onset, prolonged duration of sensory and motor block and improved postoperative analgesia, without associated adverse effects at the dose used.

Dexmedetomidine as adjunct to ilioinguinal/iliohypogastric nerve blocks for pediatric inguinal hernia repair: an exploratory randomized controlled trial

BACKGROUND

Adult meta-analysis has identified dexmedetomidine as a potentially useful adjunct to prolong the duration of peripheral nerve blocks. However, no data exist regarding the adjuvant use of dexmedetomidine in the setting of pediatric peripheral nerve blocks.

METHODS

Using a prospective, randomized, double-blind design, children (1½-8 years, ASA 1-2) scheduled for outpatient inguinal hernia repair were randomized to receive either an ultrasound-guided ilioinguinal/iliohypogastric nerve block (IINB) with plain ropivacaine 0.197% (Group LA; n = 21) or ropivacaine 0.197% with adjunct dexmedetomidine 0.3 μg·kg(-1) (Group LAD; n = 22). The primary endpoint of the study was time to first postoperative administration of supplemental analgesia (FPASA) triggered by a pain score ≥4 (CHIPPS or NRS scale). Intention-to-treat (ITT) analysis was decided as the primary statistical analysis of the data.

RESULTS

The median time to FPASA was prolonged by 88% following the use of adjunct dexmedetomidine (4.0 and 7.6 h in group LA and LAD, respectively) (P = 0.0717). Patients in Group LA displayed a significantly higher number of patients with a CHIPPS score ≥4 in the PACU (7 vs 0; P = 0.0029) as well as a higher incidence of PAED (4 vs 0; P = 0.0485) when compared to patients in Group LAD. No adverse events were recorded in any of the study groups.

CONCLUSIONS

The use of dexmedetomidine as an adjunct to an IINB resulted in reduced incidences of CHIPPS pain scores ≥4 and PAED scores of ≥11 during early recovery following pediatric inguinal hernia repair. In addition, the use of adjunct dexmedetomidine was associated with a prolongation of the period to first supplemental analgesia demand. The results of the present exploratory study must be viewed as preliminary and need further validation by future larger sized studies and/or meta-analysis.

Adjuncts should always be used in pediatric regional anesthesia

A number of different adjuncts to local anesthetics can be used to prolong and optimize postoperative pain relief following regional anesthesia in children. The present text provides a slightly opinionated but evidence-based argument in favor of this practice.

Association of clonidine and ropivacaine in brachial plexus block for shoulder arthroscopy

BACKGROUND AND OBJECTIVES

Arthroscopy for shoulder disorders is associated with severe and difficult to control pain, postoperatively. The addition of clonidine to local anesthetics for peripheral nerve block has become increasingly common, thanks to the potential ability of this drug to reduce the mass of local anesthetic required and to prolonging analgesia postoperatively. The present study aimed to evaluate the success of brachial plexus block for arthroscopic rotator cuff surgery using local anesthetic with or without clonidine.

METHOD

53 patients of both genders, between 18 and 70 years old, American Society of Anesthesiologists I or II, who were scheduled to undergo arthroscopic shoulder surgery were selected. Patients were then randomized into two groups. The verbal numerical pain scale and the presence of motor block were obtained in the post-anesthetic recovery room and 6, 12, 18 and 24h postoperatively.

RESULTS

The association of clonidine (0.15mg) to a solution of 0.33% ropivacaine (30mL) in brachial plexus block for shoulder arthroscopy has not diminished the visual numeric pain scale values, nor the need for opioid rescue postoperatively. There was a lower incidence of nausea/vomiting postoperatively and a significant motor block time prolongation in the group of patients who received clonidine as adjuvant.

CONCLUSIONS

The use of brachial plexus block with local anesthetic for analgesic postoperative control is well established in the literature. The addition of clonidine in the dose proposed for prolongation of the analgesic effect and reduction of opioid rescue proved unhelpful.

Adjuvants in pediatric regional anesthesia

SUMMARY Local anesthetics have a limited duration of action. Adjuvants are used to prolong the duration of action and to augment analgesia allowing lower concentrations of local anesthetic to be used. Adjuvants have been used more extensively with neuraxial blocks, particularly caudal epidural blocks, but more recently to supplement peripheral nerve blocks. Intrathecal adjuvants are not covered in this review since spinal anesthesia is not widely used in children except in ex-premature infants. Morphine is the historical gold-standard with which other adjuvants are compared. Clonidine is most useful and is becoming increasingly popular, while the side-effect profile of other agents reduces their utility. Concerns with regard to the neurotoxicity of ketamine in animal models has led to its withdrawal in some countries.

Prolonged nerve blockade in a patient treated with lithium

We report a case of a patient, chronically treated with oral lithium, who presented with an extremely prolonged (42-hour) duration of sensory and motor paralysis following an uneventful infraclavicular block for hand surgery that was performed under ultrasound guidance using bupivacaine and lidocaine. Due to its direct effect on nerve conduction of action potential, we propose that lithium may have had a role in the unusually prolonged duration of a peripheral nerve block.

Battlefield analgesia: a brief review of current trends and concepts in the treatment of pain in US military casualties from the conflicts in Iraq and Afghanistan

SUMMARY Battlefield analgesia and post-injury pain management is a high priority within the military medical community. The combined military services of the USA have developed a Pain Task Force and clinical practice guidelines to ensure that adequate analgesia is provided to our wounded soldiers as far forward as the point of injury on the battlefield. As a result of this emphasis, novel analgesic techniques and equipment have led to improved pain management. Continuous peripheral nerve blocks, intranasal ketamine, battlefield acupuncture and other adjuncts have all been utilized safely and successfully. The ability to provide rapid analgesia as early in the course of injury as possible not only helps with the immediate pain of the soldier, but potentially minimizes the risk of developing chronic postinjury pain. During the long medical evacuation system the risks of both undertreatment and overtreatment of pain are very real. Future studies and observation will help to delineate best treatment regimens and pave the way for the next generation of medical providers to positively impact a soldier’s recovery. This article is written from the perspective of the USA with a focus on the conflicts in Afghanistan (Operation Enduring Freedom) and Iraq (Operation Iraqi Freedom).

Clonidine does not improve quality of ropivacaine axillary brachial plexus block in children

BACKGROUND

The addition of clonidine to peripheral nerve blocks is controversial in children.

OBJECTIVE

The aim of our study was to evaluate the effect of clonidine added to ropivacaine in pediatric axillary brachial plexus block (ABPB).

METHODS

Children aged 1-6 years, scheduled to undergo forearm or hand surgery, were recruited into this prospective, double-blind controlled trial. Patients were randomly allocated to receive an ABPB either with ropivacaine 0.2% 0.4 ml · kg(-1) plus saline in 1 ml (RS) or ropivacaine 0.2% 0.4 ml · kg(-1) plus clonidine 1 μg · kg(-1) in 1 ml (RC). Primary endpoints were quality of postoperative analgesia as assessed by pain scores and total 24-h postoperative analgesia requirements. Secondary outcomes were time to first analgesia request and duration of motor blockade.

RESULTS

Sixty patients were recruited (n = 30 per group) into the study. Pain scores were comparable throughout the first 24 h between the two groups. Ten children in the (RS) and six in (RC) groups required supplementary analgesia during the first 24 h (P = 0.24). Children who required further analgesia did so after 288 ± 94 min in the (RS) and 437 ± 204 min in the (RC) group (P = 0.06). There was no difference in the duration of motor block [186 ± 71 and 154 ± 56 min, P = 0.12 for (RS) and (RC), respectively].

CONCLUSION

Ropivacaine (0.2% 0.4 ml · kg(-1) ) for ABPB provides sufficient postoperative analgesia in children scheduled for forearm or hand surgery. The addition of clonidine to ABPB does not improve overall postoperative analgesia but may increase the time to first analgesia request.

Sciatic lateral popliteal block with clonidine alone or clonidine plus 0.2% ropivacaine: effect on the intra-and postoperative analgesia for lower extremity surgery in children: a randomized prospective controlled study

BACKGROUND

The effect of adding clonidine to local anesthetics for nerve or plexus blocks remains unclear. Most of the studies in adults have demonstrated the positive effects of clonidine on intra- and postoperative analgesia when used as an adjunctive agent or in some cases as a single to regional techniques. In the pediatric population, there are only few trials involving clonidine as an adjunct to regional anesthesia, and the analgesic benefits are not definite in this group of patients. The evidence concerning perineural administration of clonidine is so far inconclusive in children, as different types and volume of local anesthetic agents have been used in these studies. Moreover, the efficacy of regional anesthesia is largely affected by the operator's technique, accuracy and severity of operation.

METHODS

The use of clonidine alone or combined with 0.2% ropivacaine for effective analgesia after mild to moderate painful foot surgery was assessed in 66 children, after combined sciatic lateral popliteal block (SLPB) plus femoral block. The patients were randomly assigned into three groups to receive placebo, clonidine, and clonidine plus ropivacaine. Time to first analgesic request in the groups was analyzed by using Kaplan-Meier and the log-rank test (mean time, median time, 95% CI).

RESULTS

In our study, clonidine administered alone in the SLPB seems promising, maintaining intraoperatively the hemodynamic parameters SAP, DAP, HR to the lower normal values so that no patient needed nalbuphine under 0.6 MAC sevoflurane anesthesia, and postoperatively without analgesic request for a median time of 6 hours. In addition, clonidine administered as adjuvant enhances ropivacaine's analgesic effect for the first postoperative day in the majority of children (p = 0.001). Clonidine and clonidine plus ropivacaine groups also didn't demonstrate PONV, motor blockade, and moreover, the parents of children expressed their satisfaction with the excellent perioperative management of their children, with satisfaction score 9.74 ± 0.45 and 9.73 ± 0.70 respectively. On the contrary all the patients in the control group required rescue nalbuphine in the recovery room, and postoperatively, along with high incidence of PONV, and the parents of children reported a low satisfaction score (7.50 ± 0.70).

CONCLUSIONS

Clonidine appears promising more as an adjuvant in 0.2% ropivacaine and less than alone in the SLPB plus femoral block in children undergoing mild to moderate painful foot surgery, with no side effects.

TRIAL REGISTRATION

ClinicalTrials.gov, ISRCTN90832436, (ref: CCT-NAPN-20886).

Intra and postoperative outcome of adding clonidine to bupivacaine in infraorbital nerve block for young children undergoing cleft lip surgery

Aims and Context:

To evaluate the efficacy of adding clonidine to bupivacaine in bilateral infraorbital nerve block for hemodynamic changes, requirement of opioids, volatile agent, and muscle relaxants intraoperatively and relief of pain postoperatively

Setting and Design:

Prospective, randomized, double-blind study.

Methods:

Fifty pediatric patients aged less than 24 months undergoing elective cleft lip repair were randomly allocated to two groups of 25 each. After tracheal intubation, group A received bilateral infraorbital nerve block with 1 ml solution of clonidine (1 μg/kg) and bupivacaine 0.25%, and group B received 1 ml of 0.25% bupivacaine. Hemodynamic parameters, intraoperative requirement of volatile anesthetic agent, muscle relaxant, and analgesic were recorded. Pain was assessed postoperatively using the Face, Legs, Activity, Cry, Consolability scale till the first rescue drug was given.

Statistical Analysis:

Two sample unpaired t-test and the correlation r test.

Results:

The duration of analgesia from the time of administration of block in group A was 667.72 ± 210.74 min compared to 558.48 ± 150.28 min in group B (P<0.05).

Conclusion:

Addition of clonidine as an adjunct to local anesthetic significantly decreased the requirement of other anesthetic drugs and significantly prolonged the duration of postoperative analgesia without any adverse effects.

A randomized controlled double-blinded prospective study of the efficacy of clonidine added to bupivacaine as compared with bupivacaine alone used in supraclavicular brachial plexus block for upper limb surgeries

We compared the effects of clonidine added to bupivacaine with bupivacaine alone on supraclavicular brachial plexus block and observed the side-effects of both the groups. In this prospective, randomized, double-blinded, controlled trial, two groups of 25 patients each were investigated using (i) 40 ml of bupivacaine 0.25% plus 0.150 mg of clonidine and (ii) 40 ml of bupivacaine 0.25% plus 1 ml of NaCl 0.9, respectively. The onset of motor and sensory block and duration of sensory block were recorded along with monitoring of heart rate, non-invasive blood pressure, oxygen saturation and sedation. It was observed that addition of clonidine to bupivacaine resulted in faster onset of sensory block, longer duration of analgesia (as assessed by visual analogue score), prolongation of the motor block (as assessed by modified Lovett Rating Scale), prolongation of the duration of recovery of sensation and no association with any haemodynamic changes (heart rate and blood pressure), sedation or any other adverse effects. These findings suggest that clonidine added to bupivacaine is an attractive option for improving the quality and duration of supraclavicular brachial plexus block in upper limb surgeries.

Regional anaesthesia and analgesia in the neonate

A large number of published studies have shown that the use of diverse regional anaesthetic techniques is associated with high-quality pain relief following the different types of surgery and painful procedures that are commonly performed in neonatal patients. Apart from pain, few studies have examined other outcomes in this setting. Some data suggest a benefit with regional anaesthesia. In a retrospective study, Bosenberg et al. found that the use of epidural analgesia in neonatal patients undergoing tracheo-oesophageal fistula repair resulted in a reduced need for postoperative mechanical ventilation. Furthermore, epidural analgesia was found to be associated with a significant and beneficial modification of the neuroendocrine surgical stress response after major abdominal surgery in infants when compared to postoperative morphine infusions. The use of local anaesthetics in association with neonatal circumcision has also shown a benefit as neonates not treated with eutectic mixture of lidocaine and prilocaine (EMLA) or a penile block had an exaggerated pain response to later vaccinations as compared with neonates treated with a local anaesthetic technique. Finally, safety data generated from large, prospective studies and audits clearly show that the use of paediatric regional anaesthetic techniques is associated with adequate safety also in neonatal patients. In conclusion, a large variety of local and regional anaesthetic techniques can be safely used in neonatal patients. The use of such techniques must obviously be associated with sufficient knowledge about the various techniques, as well as adherence to adequate dosage guidelines and other safety precautions. However, if these prerequisites are met, regional anaesthesia may offer great advantages to our smallest and most vulnerable patients.

Treatment of acute pediatric pain

Pediatric neurologists frequently treat acute pain in children. A broad range of medication options is available including nonsteroidal anti-inflammatory drugs, opioids, and other analgesic adjuvants, such as antidepressants and antiepileptics. This article reviews the physiology underlying the experience of pain and compares the pharmacologic mechanisms and properties of these medications, providing a framework for developing effective multimodal medical treatment approaches to pain in children.

Ultrasound guidance for pediatric peripheral nerve blockade

There is an increasing trend in the use of peripheral nerve blockade for postoperative analgesia in children, and the use of ultrasound guidance to perform peripheral nerve blocks is gaining popularity. A thorough knowledge of anatomy will help in performing the appropriate block, and will also aid in better use and understanding of ultrasound guidance. In this article, we briefly review the use of ultrasound guidance to perform common upper and lower extremity and truncal blocks.

Pharmacologic management of acute pediatric pain

The accurate assessment and effective treatment of acute pain in children in the hospital setting is a high priority. During the past 2 to 3 decades, pediatric pain management has gained tremendous knowledge with respect to the understanding of developmental neurobiology, developmental pharmacology the use of analgesics in children, the use of regional techniques in children, and of the psychological needs of children in pain. A wide range of medications is available to treat a variety of pain types. This article provides an overview of the most common analgesic medications and techniques used to treat acute pain in children.

Continuous peripheral nerve blockade for inpatient and outpatient postoperative analgesia in children

BACKGROUND

This is an audit of the continuous peripheral nerve blockade (CPNB) program that was implemented at our institution to provide postoperative analgesia after orthopedic procedures in children.

METHODS

We reviewed the departmental regional anesthesia registry and the medical records of consecutive children who received CPNB for postoperative analgesia at The Children's Hospital of Philadelphia between February 2003 and July 2006. Patients were prospectively followed until cessation of the effects of CPNB and/or resolution of any related complications. Data collected contemporaneously included presence of sensory and motor blockade, pain scores in inpatients, opioid administration, and complications related to CPNB.

RESULTS

A total of 226 peripheral nerve catheters were placed in 217 patients. One hundred eight patients (112 catheters) were discharged home with CPNB. The ages ranged from 4 to 18 yr (13.7 +/- 3.4). Local anesthetic solution (0.125% bupivacaine [n = 164], 0.1% ropivacaine [n = 12], or 0.15% ropivacaine [n = 27]) was infused at an initial rate of 2-12 mL/h based on patients' weights and locations of catheters. The mean duration of local anesthetic infusion was 48.4 +/- 29.3 h (range 0-160 h). The percentage of patients who did not require any opioids in the first 8, 24, and 48 h after surgery was 56%, 26%, and 21%, respectively. The incidence of nausea and vomiting was 14% (13% in outpatients, 15% in inpatients). Complications were noted in 2.8% of patients. Three patients had prolonged numbness (>24 h) that resolved spontaneously; one developed superficial cellulitis that resolved with a course of antibiotics; one had difficulty removing the catheter at home and one developed tinnitus 24 h after starting CPNB that resolved quickly after clamping of the catheter followed by removal.

CONCLUSION

It is feasible to implement a CPNB program to provide an alternative method of inpatient and outpatient postoperative analgesia after orthopedic surgery in children when appropriate expertise is available. Patient and family education along with frequent follow-up are crucial to detect and address adverse events promptly.