Addition of clonidine or fentanyl to local anaesthetics prolongs the duration of surgical analgesia after single shot caudal block in children

Clonidine as an Additive to Local Anesthetics in Caudal Block for Postoperative Analgesia in Pediatric Surgery: A Systematic Review and Meta-Analysis

Background: Clonidine is an anesthetic with favorable efficacy and safety profiles for caudal epidural block, but comparisons with other adjuvants need to be confirmed in pediatric patients. Aim: To investigate the effects of clonidine as an adjuvant in caudal epidural block to improve the intraoperative and postoperative analgesia in pediatric surgery. Methods: PubMed, Embase, and the Cochrane Library were searched for available papers published up to February 2021. The outcomes were pain score, duration of analgesia, complications, and number of analgesic requirements. The meta-analysis was performed using random-effects models. Results: Fifteen randomized controlled trials (RCTs) were included. There were no differences between clonidine and the control drug regarding the duration of analgesia (SMD = -0.71, 95%CI: -1.64, 0.23; I ² = 95.5%, P_{heterogeneity} < 0.001), pain score (SMD = 0.35, 95%CI: -0.28, 0.98; I ² = 80.8%, P_{heterogeneity} < 0.001), and requirement for additional analgesia (OR = 8.77, 95%CI: 0.70, 110.58, I ² = 81.9%, P_{heterogeneity} = 0.004), but using clonidine resulted in fewer complications than the control drugs (OR = 0.33, 95%CI: 0.20, 0.54, I ² = 21.8%, P_{heterogeneity} = 0.217). The sensitivity analysis showed that the results were robust. A publication bias was observed. Conclusion: Clonidine has the same efficacy as the other adjuvants for caudal epidural block for pediatric surgery but fewer complications. These results support clonidine as an adjuvant to local anesthetic, but additional studies should be conducted.

Three-step tumescent local anesthesia technique for inguinal hernia repair

The optimal method of anesthesia for inguinal hernia repair is still controversial. We have developed "three-step tumescent local anesthesia (TLA) technique" for inguinal hernia repair, and recently showed that this technique is acceptable in view of short- and long-term clinical outcomes. Our study included 273 consecutive cases (290 sides) of elective inguinal hernia repair performed under the newly developed technique between September 2003 and May 2019, and overall clinical outcomes were considered to be safe and feasible. Herein, we report the surgical procedure of "three-step TLA technique." Briefly, we rapidly inject the diluted solution of local anesthetic and epinephrine step-by-step into the three following closed tissue space. Initially, 80 mL injection into the subcutaneous tissue before skin incision (Step 1). After the external oblique fascia is exposed, injection of 20 mL into the inguinal canal before the external oblique fascia is incised and opened (Step 2). The hernia sac and spermatic cord are then dissected, and the blunt dissection of the preperitoneal space is made by injecting 20 mL under the internal inguinal ring (Step 3), followed by placing a gauze into the preperitoneal space, creating the space for mesh placement. We consider that the most important point of this technique is achieved through the rapid injection of TLA solution into each closed tissue space, which makes for easier dissection, hemostasis, and good pain control.

Stepwise Local Anesthesia for Percutaneous Endoscopic Interlaminar Discectomy: Technique Strategy and Clinical Outcomes

BACKGROUND

Due to suboptimal pain control under conventional local anesthesia, percutaneous endoscopic interlaminar discectomy is typically performed under general anesthesia. The purpose of this study was to develop a stepwise approach of local anesthesia for endoscopic interlaminar discectomy and evaluate its efficacy.

METHODS

A stepwise local anesthesia was developed, which mainly includes 3 steps: conventional local anesthesia from skin to laminae, epidural injection, and nerve root block. From June 2015 to May 2017, consecutive patients who underwent endoscopic interlaminar discectomy were included. Local anesthesia or general anesthesia was used based on patients' preference. Anesthetic effectiveness was evaluated as excellent, good, or poor, and adverse events were recorded. Hospitalization expense was compared between the 2 groups. Clinical outcomes were assessed using the Visual Analog Scale and the Oswestry Disability Index.

RESULTS

There were 98 patients included in the study. Among them, 48 received stepwise local anesthesia and the other 50 received general anesthesia. In the stepwise local anesthesia group, 40 (83.3%) patients rated anesthetic effectiveness as excellent, 7 (14.6%) as good, and 1 (2.1%) as poor. Nine patients had complications that may be associated with local anesthesia, including dyspnea, temporary paresis of legs, and temporary worsened dysesthesia or numbness in legs. After surgery, the patients' leg pain and Oswestry Disability Index significantly improved in both groups. On average, hospitalization expense was approximately 20% less when local anesthesia was used, as compared with using general anesthesia.

CONCLUSIONS

The stepwise local anesthesia can achieve satisfactory pain control and seems to be a good choice for endoscopic interlaminar discectomy.

A Comparative Clinical Study between Clonidine and Tramadol with Bupivacaine in Caudal Epidural for Postoperative Analgesia in Pediatric Surgery

Context

Adjuvants to bupivacaine for single shot caudal block in children.

Aims

This study entitled was conducted to compare the effects of addition of tramadol to bupivacaine over addition of clonidine to bupivacaine as a single shot caudal block in children.

Settings and Design

Sixty children of ASA grade I and II in the age group of 2-12 years coming for various infra-umbilical surgeries were included.

Materials and Methods

They were divided into two groups of 30 each. Group BC received caudal bupivacaine 0.25% 0.5ml/kg with clonidine 2 mcg/kg Group BT received caudal bupivacaine 0.25% 0.5 ml/kg with tramadol 2 mg/kg. The main parameters studied were hemodynamic changes, duration of post-operative analgesia and incidence of adverse effects.

Statistical Analysis Used

The results of continuous variables are given as mean ± SD and proportion as percentage. The difference between the two groups was assessed by student's - t test and chi-square test.

Results

The mean duration of post-operative analgesia in group BT was statistically significant (P <0.001), reducing the requirement of analgesics in group BT. There was no difference in sedation score, nausea, vomiting, urinary retention.

Conclusions

The present study demonstrated that caudal administration of bupivacaine 0.25% 0.5 ml/kg with tramadol 2 mg/kg resulted in superior analgesia with longer duration of action and reduced requirement of analgesics in first 24 hours postoperatively when compared with 0.25% bupivacaine 0.5 ml/kg with clonidine 2 mcg/kg.

The Efficacy and Safety of Dexmedetomidine Combined with Bupivacaine on Caudal Epidural Block in Children: A Meta-Analysis

BACKGROUND This meta-analysis was conducted to evaluate the analgesics effect and safety of dexmedetomidine (DEX) combined with bupivacaine (BU) on caudal epidural block. MATERIAL AND METHODS Published studies were identified using the PubMed, EMBASE, Web of Science, and the Cochrane Library from inception until October 2017. Relative risk (RR), the standardized mean difference (SMD), and the corresponding 95% confidence interval (CI) were calculated using the STATA 12.0. RESULTS Ten randomized controlled trials (RCTs) were selected for this meta-analysis, involving a total of 691 patients. There was a longer duration of postoperative analgesia in children receiving DEX (SMD=3.19, 95% CI: 2.16-4.22, P<0.001). Furthermore, there was a lower number of patients requiring rescue analgesics in the (BU) + (DEX) group (6 hours: RR=0.09, 95% CI: 0.05-0.17, P<0.001; 12 hours: RR=0.50, 95% CI: 0.32-0.79, P=0.003; 24 hours: RR=0.66, 95% CI: 0.51-0.85, P=0.002). Finally, the occurrence of adverse events, between BU and DEX + BU group, was not statistically significant (RR=0.96, 95% CI: 0.58-1.58, P>0.05). CONCLUSIONS DEX seems to be a promising adjuvant to BU increase duration of caudal analgesia without an increase in side effects in children. However, the result may be influenced by clinical heterogeneity. More large-scale, multicenter, approaching, double-blinded RCTs are required to confirm our results.

Clonidine versus other adjuncts added to local anesthetics for pediatric neuraxial blocks: a systematic review and meta-analysis

Background

Clonidine is a common adjunct to local anesthetics for pediatric neuraxial block; however, the pros and cons between clonidine and other adjuncts remain unclear. Thus, we performed this meta-analysis of randomized controlled trials to assess the efficacy and adverse effects between clonidine and other adjuncts added to local anesthetics.

Materials and methods

The systematic search, data extraction, critical appraisal, and pooled analysis were performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Randomized controlled studies were searched in Cochrane (to present), Medline (1946 to present), Embase (1974 to present), and Biosis (1995 to present). Relative risks (RRs), standard mean difference (SMD), and associated CIs were calculated using RevMan statistical software to assess continuous and dichotomous data. Heterogeneity in studies was measured by forest plots and I² values. Subgroup analysis was performed for continuous and dichotomous variables, while meta-regression was applied for continuous data with high I² values.

Results

A total of 15 randomized controlled studies met the inclusion criteria. There was a longer duration of postoperative analgesia in the clonidine group than for other adjuncts (SMD=1.54, p=0.005, I²=96%). The number of patients requiring rescue analgesia was lower in the clonidine group without the addition of epinephrine (RR=0.55, p=0.0002, I²=0), while the RR for the comparison with epinephrine was significant (p=0.62, I²=95%). The duration of motor block was longer in the clonidine group (mean difference [MD]=1.06, p<0.00001, I²=0). The clonidine group also had a lower incidence of postoperative nausea and vomiting (PONV; RR=0.49, p<0.00001, I²=0). Postoperative bradycardia, hypotension, and urinary retention were not significantly different between clonidine and other adjuncts (p>0.05).

Conclusion

Clonidine, compared with other adjuncts, added to local anesthetics for neuraxial block, provides a longer duration of postoperative analgesia with lower incidence of PONV. However, the duration of motor block may also be prolonged by clonidine.

A Comparative Study for the Analgesic Efficacy and Safety Profile of Fentanyl versus Clonidine as an Adjuvant to Epidural Ropivacaine 0.75% in Lower Abdominal Surgeries

CONTEXT

Different adjuvants are coadministered with local anesthetics to improve the speed of onset and duration of analgesia, and to reduce the dose, the selection of which is often left to the choice of an anesthesiologist.

AIM

The aim of this study was to compare the analgesic efficacy and safety profile of fentanyl and clonidine as an adjuvant to epidural ropivacaine anesthesia.

SETTING AND DESIGN

With institutional ethical committee clearance, a prospective, randomized, placebo-controlled double-blind clinical study was conducted at Vivekananda Polyclinic and Institute of Medical Sciences, Lucknow.

MATERIAL AND METHODS

Two groups with thirty patients each were randomly allocated to receive 15-20 ml of 0.75% ropivacaine with 75 μg clonidine or 15-20 ml of 0.75% ropivacaine with 75 μg fentanyl, respectively. Block characteristics such as onset of analgesia, maximum level of sensory blockade, complete motor blockade, hemodynamic, time to two-segment regressions, time for rescue analgesia, time to complete motor recovery, and side effects were analyzed.

RESULTS

Results showed that the onset of blockade is faster when fentanyl is used as additives. Time for two-segment regression was earlier in fentanyl group but time for rescue analgesia was longer in clonidine group.

STATISTICAL ANALYSIS

Two groups were compared by Student's t-test and Chi-square test; ANOVA and significance of mean difference bet were done by Newman-Keuls test.

CONCLUSION

Addition of clonidine to epidural ropivacaine provides superior analgesia than the addition of fentanyl to epidural ropivacaine without much difference in side effect profile.

Lung or Heart-Lung Transplant in Pulmonary Arterial Hypertension: What Is the Impact of Systemic Sclerosis?

OBJECTIVES

Little is known about recipient characteristics and outcomes of patients with pulmonary arterial hypertension undergoing lung transplant, particularly those with systemic sclerosis-associated disease. Here, we describe the characteristics and outcomes of patients with pulmonary arterial hypertension undergoing lung transplant, focusing on systemic sclerosis-associated disease.

MATERIALS AND METHODS

This retrospective study included pulmonary arterial hypertension patients undergoing lung or heart-lung transplant between July 1992 and August 2013 at a single center.

RESULTS

We evaluated 51 patients with pulmonary arterial hypertension (37.3% males; mean age of 45.3 ± 11.9 y). Of 51 patients, 9 (17.6%) had systemic sclerosis-associated pulmonary arterial hypertension. Pulmonary arterial hypertension patients without systemic sclerosis-associated disease had higher mean pulmonary arterial pressure (P = .002), higher pulmonary vascular resistance (P = .008), and were more likely to have severe right ventricular systolic dysfunction (P = .006) than individuals with the disease. Mean hospital stay posttransplant was similar in the 2 groups (42.2 ± 43.3 vs 43.1 ± 19.4 d; P = .20). Higher pretransplant creatinine clearance (P = .0005), forced vital capacity (P = .01), and absence of vasopressor/inotrope use (P = .03) were associated with shorter hospital stay. Mortality for pulmonary arterial hypertension patients with versus without systemic sclerosis-associated disease was 0% versus 13% at 1 year, 29% versus 24% at 2 years, and 86% versus 53% at 5 years. Female sex (hazard ratio, 0.23; 95% confidence interval, 0.08-0.68) and less severe tricuspid regurgitation (hazard ratio, 0.31; 95% confidence interval, 0.11-0.89) were independently associated with long-term survival.

CONCLUSIONS

Pulmonary arterial hypertension patients with versus without systemic sclerosis-associated disease have comparable short-term and 2-year outcomes after lung or heart-lung transplant. Female sex and less severe tricuspid regurgitation were independently associated with better long-term survival. These outcomes did not vary when adjusted for the year of transplant.

Effect of Addition of Fentanyl and Clonidine to Local Anesthetic Solution in Peribulbar Block

Objective:

To compare the effect of addition of fentanyl and clonidine as adjuvants to bupivacaine and lignocaine in peribulbar block.

Methods:

The study was conducted on 105 adult patients of either sex, of ASA grade I and II undergoing ophthalmic surgeries. Patients were randomly divided into 3 groups of 35 each. All the patients were given peribulbuar block with 5ml lignocaine 2% +3 ml bupivacaine 0.5% +1 ml hyaluronidase (250 IU). In addition to this 1 ml normal saline was added to Group S, 25 μg fentanyl to Group F and 25 μg clonidine to Group C. Onset and duration of globe and lid akinesia, duration of sensory blockage and analgesia, hemodynamic parameters, number of rescue analgesic and visual analogue score were recorded.

Results:

The mean time of onset of globe and lid akinesia was significantly faster in group F and group C compared to group S, mean duration of globe and lid akinesia was longer in Group F (207.71 + 13.54 and 143.14 + 7.86 min) and group C (213.52 + 14.52 and 162.06 + 17.1 min) compared to group S (117.78 + 10.42 and 87.64 + 9.76 min). The mean duration of analgesia was significantly longer in group F (217.71 + 12.67) and C (258.82 + 14.50 min) as compared to group S (131.39 + 9.63 min).

Conclusion:

Addition of fentanyl or clonidine as adjuvant to local anaesthetic in peribulbar block provides faster onset and prolonged analgesia compared to local anaesthetic alone.

A Ropivacaine-Lidocaine Combination for Caudal Blockade in Haemorrhoidectomy

A single dose of caudal lidocaine does not provide a sufficiently long anaesthetic duration and is not generally used for complicated anorectal surgery. This study evaluated the safety and efficacy of a ropivacaine–lidocaine combination for caudal anaesthesia in patients undergoing haemorrhoidectomy. A total of 287 haemorrhoid patients with successful initial caudal anaesthesia were randomized to receive either a mixture of 0.375% ropivacaine and 1.0% lidocaine (ropi–lido group; n = 146) or 1.0% lidocaine alone (placebo-lido group; n = 141). Significantly fewer patients in the ropi–lido group required intra-operative supplemental anaesthesia than in the placebo-lido group. Patients treated with the ropivacaine–lidocaine combination had significantly lower scores for pain at each post-operative time point, and a longer mean time to the first requirement for post-operative analgesic than patients in the placebo-lido group. These results suggest that caudal anaesthesia with a combination of ropivacaine and lidocaine is a safe and effective method of inducing anaesthesia during haemorrhoidectomy.

Dexmedetomidine as an adjuvant to bupivacaine in caudal analgesia in children

Context:

Postoperative pain management is becoming an integral part of anesthesia care. Various techniques of pediatric pain relief have been designed among which the most commonly practiced is caudal epidural block. Several adjuvants have been used to prolong the duration of caudal analgesia such as clonidine, neostigmine, ketamine, opioids, and ephedrine. We have designed the study using dexmedetomidine as an adjuvant to assess analgesic efficacy, duration of postoperative analgesia, hemodynamic stability, postoperative sedation, and any adverse effects in children.

Aims:

The aim is to study the effects of dexmedetomidine as an adjuvant to bupivacaine in caudal analgesia in pediatric patients posted for infraumbilical surgeries.

Settings and Design:

This is a randomized, double-blind study in which effect of dexmedetomidine is studied when added to bupivacaine in the caudal epidural block. The observations are made intraoperatively for hemodynamic stability and postoperatively for the duration of analgesia.

Subjects and Methods:

This study was conducted in 100 children of American Society of Anesthesiologists physical status I and II, aged 2–10 years, undergoing elective infraumbilical surgeries. They were divided into two groups as follows: Group A: (0.25%) bupivacaine 1 ml/kg + normal saline (NS) 1 ml. Group B: (0.25%) bupivacaine 1 ml/kg + 1 μg/kg dexmedetomidine in 1 ml NS. As this study was double-blind, patients were randomly assigned to receive either (bupivacaine + saline) or (bupivacaine + dexmedetomidine) in each group. The patients were observed for hemodynamic stability, respiratory depression, and postoperative pain using face, legs, activity, cry, consolability (FLACC) pain scale for 24 h postoperatively.

Statistical Analysis Used:

Unpaired Student's t-test.

Results:

The mean duration of effective analgesia in Group A patients was 4.33 ± 0.98 h versus 9.88 ± 0.90 h in Group B patients. Likewise, the difference in mean FLACC score of both the groups was also statistically significant, 7.21 ± 0.76 and 6.49 ± 1.72 in Group A and Group B, respectively.

Conclusion:

Dexmedetomidine as adjuvant to Bupivacaine increases duration of caudal analgesia and improves hemodynamic stability without an increase in adverse effects in children undergoing infraumbilical surgeries.

A double-blind randomized controlled trial comparing dexamethasone and clonidine as adjuvants to a ropivacaine sciatic popliteal block for foot surgery

Background and aims

A popliteal block is effective in managing postoperative pain for foot surgery, but since the duration of analgesia is limited following a single-shot popliteal fossa block technique, methods to prolong effective postoperative analgesia are mandatory. The aim of this study was to assess the effect of adjuvants to ropivacaine on the duration of sensory and motor block.

Methods

In this double-blind randomized placebo-controlled study, we evaluated the analgesic effect of clonidine or dexamethasone (DXM) when added to ropivacaine for hallux valgus surgery. After obtaining institutional ethics research board approval and written informed consent, a total of 72 patients were randomly allocated. Fifty-seven of these patients were statistically analyzed. All patients received an ultrasound-guided single-shot popliteal fossa block with 30 mL of ropivacaine 0.75%, supplemented with saline, clonidine 100 µg, or DXM 5 mg. The primary end point was time to first pain sensation. Secondary end points were time to complete sensory and motor block regression.

Results

Compared to saline, duration to first pain sensation was prolonged by 9 hours (mean ± standard deviation: 31±9 hours) (42%) in the DXM group (P=0.024) and by 6 hours (28±10 hours) (27%) in the clonidine group (P=0.024). Compared to saline, DXM prolonged both complete sensory and motor blockade by 12 hours (25±7 hours) (46%) and 13 hours (36±6 hours) (55%), respectively, while clonidine prolonged complete sensory and motor blockade by 7 hours (30±7 hours) (27%) and 2 hours (22±5 hours) (10%), respectively. DXM prolonged sensory block regression time by 6 hours (21±7 hours) (41%) and clonidine by 2 hours (17±6 hours) (13%) compared to the control group (P=0.006). Similarly, DXM prolonged motor block regression by 7 hours (25±7 hours) (46%) and clonidine by 4 hours (21±4 hours) (19%) (P<0.0001).

Conclusion

Addition of DXM and clonidine to ropivacaine significantly prolonged the duration of postoperative sensory and motor block.

Addition of fentanyl to the ultrasound-guided transversus abdominis plane block does not improve analgesia following cesarean delivery

The present study aimed to investigate whether the addition of fentanyl to the transversus abdominis plane (TAP) block procedure may improve analgesic duration following cesarean delivery. A total of 147 nulliparous women with an American Society of Anesthesiologists physical status I-II, scheduled for elective cesarean delivery under spinal anesthesia, were enrolled in the present study. All patients underwent cesarean delivery under spinal anesthesia with 10 mg bupivacaine and 10 µg fentanyl, after which the patients underwent an ultrasound-guided bilateral TAP block with either 0.375% ropivacaine (group T_R; n=48), 0.375% ropivacaine and 50 µg subcutaneous fentanyl (group T_RS_F; n=49), or a mixture of 0.375% ropivacaine and 50 µg fentanyl (2.5 µg/ml; group T_RF; n=50) per side. The TAP block formed part of a multimodal analgesic regimen comprising patient-controlled analgesia (PCA) with intravenous fentanyl, and regular treatment with diclofenac and paracetamol. The TAP block was performed in the midaxillary line using an in-plane technique. The primary outcome was the time to the first PCA, whereas secondary outcomes were the cumulative and interval PCA consumptions, visual analogue scale (VAS) pain scores at rest and during movement, side effects assessed at 2, 6, 12, 24 and 48 h postoperatively, and patient satisfaction with postoperative analgesia. No significant differences were observed in the median time to the first PCA among the three groups (P=0.640), which were 150 min (70-720 min) in group T_R, 165 min (90-670 min) in group T_RS_F, and 190 min (70-680 min) in group T_RF. Fentanyl consumption, VAS pain scores, side effects and patient satisfaction were similar among the three groups; however, the demand for fentanyl was significantly decreased in the T_RS_F and T_RF groups at 2 h postoperatively (P=0.001 and 0.002, respectively), as compared with group T_R. No complications attributed to the TAP block were detected. In conclusion, the results of the present study suggested that the addition of 2.5 µg/ml fentanyl to the TAP block procedure was unable to improve analgesia following cesarean delivery under spinal anesthesia.

Comparison of caudal and intravenous dexamethasone as adjuvants for caudal epidural block: A double blinded randomised controlled trial

Background and Aims:

Dexamethasone has a powerful anti-inflammatory action with significant analgesic benefits. The aim of this study was to compare the efficacy of dexamethasone administered through intravenous (IV) and caudal route on post-operative analgesia in paediatric inguinal herniotomy patients.

Methods:

One hundred and five paediatric patients undergoing inguinal herniotomy were included and divided into three groups. Each patient received a single caudal dose of ropivacaine 0.15%, 1.5 mL/kg combined with either corresponding volume of normal saline (Group 1) or caudal dexamethasone 0.1 mg/kg (Group 2) or IV dexamethasone 0.5 mg/kg (Group 3). Baseline, intra- and post-operative haemodynamic parameters, pain scores, time to rescue analgesia, total analgesic consumption and adverse effects were evaluated for 24 h after surgery. Unpaired Student's t-test and analysis of variance were applied for quantitative data and Chi-square test for qualitative data. Time to first analgesic administration was analysed by Kaplan–Meier survival analysis and log-rank test.

Results:

Duration of analgesia was significantly longer (P < 0.001), and total consumption of analgesics was significantly lower (P < 0.001) in Group II and III compared to Group I. The incidence of nausea and vomiting was higher in Group I (31.4%) compared to Group II and III (8.6%).

Conclusions:

Addition of dexamethasone both caudally or intravenously as an adjuvant to caudal 0.15% ropivacaine significantly reduced the intensity of post-operative pain and prolonged the duration of post-operative analgesia with the significant advantage of caudal over IV route.

A comparative study of dexmedetomidine and fentanyl as adjuvants to levobupivacaine for caudal analgesia in children undergoing lower limb orthopedic surgery

Background:

Levobupivacaine is an effective local anesthetic agent with less systemic toxicity than racemic bupivacaine, but it has short postoperative analgesic duration. Dexmedetomidine and fentanyl are promising adjuncts to provide excellent and prolonged postoperative caudal analgesia. This study compared the effects of caudal levobupivacaine plus dexmedetomidine and levobupivacaine plus fentanyl for postoperative analgesia and sedation in children undergoing lower limb orthopedic surgery.

Patients and Methods:

Ninety children, whose age ranged from 1 to 7 years, American Society of Anesthesiologists I-II, undergoing orthopedic lower limb surgery under general anesthesia received caudal block for postoperative analgesia. The children were randomly allocated into three groups: Group L (control) received 0.75 ml/kg levobupivacaine 0.25% diluted in saline; Group LD received 0.75 ml/kg levobupivacaine 0.25% with dexmedetomidine 1 μg/kg; and Group LF received 0.75 ml/kg levobupivacaine 0.25% with fentanyl 1 μg/kg. Following the administration of the drugs; hemodynamic variables, the total anesthesia time, sedation score, Face, Legs, Activity, Cry, Consolability score, duration of analgesia, and side effects were recorded.

Results:

Demographically, all the groups were comparable, both the baseline and the intraoperative hemodynamic profile were similar in all groups. The mean duration of analgesia and the mean sedation score in the Group LD were significantly greater as compared to both the other groups.

Conclusion:

Dexmedetomidine may be a better additive to levobupivacaine than fentanyl for caudal postoperative analgesia, arousable sedation with comparable hemodynamic and side effect profile in children.

Caudal-epidural bupivacaine versus ropivacaine with fentanyl for paediatric postoperative analgesia

Background and Aims:

Caudal-epidural, the most commonly used regional analgesia technique, is virtually free of measurable hemodynamic effects, thus adding a new dimension to the evolving necessity of pediatric postoperative pain management. Though, bupivacaine is the most commonly used drug for this purpose, ropivacaine has emerged as a safer alternative, with the addition of opioids, like fentanyl, increasing the effective duration of analgesia. With this overview, our present study was designed to compare the postoperative analgesic efficacy of bupivacaine-fentanyl and ropivacaine-fentanyl combinations by caudal-epidural technique in pediatric infraumbilical surgeries.

Materials and Methods:

Totally, 60 pediatric patients, of either sex, aged between 2 and 8 years, American Society of Anesthesiologists physical status I and II, undergoing elective infraumbilical surgeries were assigned into two groups, Group BF receiving bupivacaine 0.25%, 0.7 ml/kg and Group RF receiving ropivacaine 0.25%, 0.7 ml/kg with fentanyl 1 μg/kg added to each group. Assessment of pain was done using “Hannallah pain scale.” Consumption of the total amount of rescue analgesic and time to requirement of the first dose, as also duration of motor blockade were noted. Perioperative hemodynamics and any adverse effects were monitored at regular intervals.

Results:

The RF Group experienced significantly longer duration of effective postoperative analgesia, with significantly shorter duration of motor blockade and lesser total analgesic requirement in comparison to the BF Group. Hemodynamically, patients in both the groups, were equally stable.

Conclusion:

Ropivacaine, with an equipotent analgesic efficacy and a lesser duration of motor block, can be used as an alternative to bupivacaine for pediatric postoperative pain care through the caudal route.

Efficacy of caudal fentanyl and ketamine on post-operative pain and neuroendocrine stress response in children undergoing infraumbilical and perineal surgery: A pilot study

BACKGROUND AND AIMS

It is well-known that neuroendocrine stress response (NESR) occurs in children and it can be modified by caudal block. However, there is paucity of literature comparing caudal fentanyl and ketamine on NESR. The present study was aimed to compare the analgesic efficacy of these caudal adjuvants and their effect on (NESR) in children undergoing infraumbilical and perineal surgery.

MATERIALS AND METHODS

A total of 60 children undergoing infraumbilical surgery were included in this randomized, double-blind study. Three groups of 20 each were assigned to receive caudal block with bupivacaine 0.25% 1 ml/kg along with either 0.9% normal saline (Group I) 1 μg/kg fentanyl (Group II) or 0.5 mg/kg ketamine (Group III). Modified visual analogue scale (VAS) was used for assessment of post-operative pain, and stress response was assessed by blood glucose, serum cortisol and insulin levels at various time intervals.

RESULTS

VAS scores were significantly lower in the ketamine group at all-time intervals upto 4 h (P < 0.05). Patients in ketamine group required rescue analgesia significantly later (8.23 h) when compared to fentanyl (5.95 h) and bupivacaine group (4.10 h). Caudal block led to significant decrease in cortisol and insulin levels within the groups however this significance was not achieved between groups.

CONCLUSION

Caudal ketamine in a dose of 0.5 mg/kg provides prolonged analgesia when compared to fentanyl 1 μg/kg. Blunting of the NESR was observed in all the groups though the indicators of the response were lowest with ketamine.

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.

Enhancement of ropivacaine caudal analgesia using dexamethasone or magnesium in children undergoing inguinal hernia repair

BACKGROUND

Caudal analgesia is the most commonly used technique providing intra- and postoperative analgesia for various pediatric infraumbilical surgical procedures but with the disadvantage of short duration of action after single injection. Caudal dexamethasone and magnesium could offer significant analgesic benefits. We compared the analgesic effects and side-effects of dexamethasone or magnesium added to caudal ropivacaine in pediatric patients undergoing inguinal hernia repair.

MATERIALS AND METHODS

A total of 105 (1-6 years) were randomly assigned into three groups in a double-blinded manner. After a standardized sevoflurane in oxygen anesthesia, each patient received a single caudal dose of ropivacaine 0.15% 1.5 mL/kg combined with either magnesium 50 mg in normal saline 1 mL (group RM), dexamethasone 0.1 mg/kg in normal saline 1 mL (group RD), or corresponding volume of normal saline (group R) according to group assignment. Postoperative analgesia, use of analgesics, and side-effects were assessed during the first 24 h.

RESULTS

Addition of magnesium or dexamethasone to caudal ropivacaine significantly prolonged analgesia duration 8 (5-11) h and 12 (8-16) h, respectively compared with 4 (3-5) h with the use of ropivacaine alone. The incidence of postoperative rescue analgesia was significantly higher in group R compared with groups RM and RD. The time to 1(st) analgesic dose was significantly longer in groups RM and RD (500 ± 190 and 730 ± 260 min) respectively compared with group R (260 ± 65 min). Group R patients achieved significantly higher Children's Hospital of Eastern Ontario Pain Scale and Faces Legs Activity Cry Consolability scores (4(th) hourly) compared with groups RM and RD patients (8(th) and 12(th) hourly, respectively).

CONCLUSION

The addition of dexamethasone or magnesium to caudal ropivacaine significantly prolonged the duration of postoperative analgesia in children undergoing inguinal hernia repair. Also the time to 1(st) analgesic dose was longer and the need for rescue postoperative analgesic was reduced and without increase in incidence of side effects.

Guided paravertebral blocks with versus without clonidine for women undergoing breast surgery: a prospective double-blinded randomized study

BACKGROUND

Paravertebral blocks (PVBs) have been introduced as an alternative to general anesthesia for breast cancer surgeries. The addition of clonidine as an adjuvant in PVBs may enhance quality and duration of analgesia and significantly reduce the consumption of analgesics after breast surgery. In this prospective randomized double-blind study, we assessed the significance of adding clonidine to the anesthetic mixture for women undergoing mastectomy.

METHODS

Sixty patients were randomized equally into 2 groups, both of which received PVB block, either with or without clonidine. Analgesic consumption was noted up to 2 weeks after the operation. A visual analog scale was used to assess pain postoperatively during the hospital stay, and a numeric rating scale was used when patients were discharged.

RESULTS

Analgesic consumption was significantly lower in the clonidine group 48 hours postoperatively with 95% confidence interval (CI) for the difference (-69.5% to -6.6%). Pain scores at rest showed significant reduction in the clonidine group during the period from 24 to 72 hours postoperatively with 95% CI for the ratios of 2 means (1.09-3.61), (2.04-9.04), and (2.54-16.55), respectively, with shoulder movement at 24, 48, and 72 hours postoperatively 95% CI for the ratio of 2 means (1.10-3.15), (1.32-6.38), and (1.33-8.42), respectively. The time needed to resume daily activity was shorter in the clonidine group compared with the control group with 95% CI for the ratio of 2 means (1.14-1.62).

CONCLUSION

The addition of clonidine enhanced the analgesic efficacy of PVB up to 3 days postoperatively for patients undergoing breast surgery.

Efficacy and safety of clonidine as additive for caudal regional anesthesia: a quantitative systematic review of randomized controlled trials

BACKGROUND

Clonidine is still the most popular additive for caudal regional anesthesia. Aim of the present quantitative systematic review was to assess the efficacy and safety of the combined use of clonidine and local anesthetics in comparison with caudal local anesthetics alone.

METHODS

The systematic search, data extraction, critical appraisal and pooled analysis were performed according to the PRISMA statement. The systematic search included the Central register of controlled trials of the Cochrane Library (to present), MEDLINE (1966 to present), EMBASE (1980 to present) and CINAHL (1981 to present). Relative risk (RR), mean difference (MD) and the corresponding 95% confidence intervals (CI) were calculated using the Revman(®) statistical software for dichotomous and continuous outcomes.

RESULTS

Twenty randomized controlled trials (published between 1994 and 2010) including 993 patients met the inclusion criteria. There was a longer duration of postoperative analgesia in children receiving clonidine in addition to local anesthetic (MD: 3.98 h; 95% CI: 2.84-5.13; P < 0.00001). Furthermore, there was a lower number of patients requiring rescue analgesics in the clonidine group (RR: 0.72; 95% CI: 0.57-0.90; P = 0.003). The incidence of complications (e.g., respiratory depression) remained very low and was not different to caudal local anesthetics alone.

CONCLUSIONS

There is considerable evidence that caudally administered clonidine in addition to local anesthetics provides extended duration of analgesia with a decreased incidence for analgesic rescue requirement and little adverse effects compared to caudal local anesthetics alone.

Involvement of imidazoline and opioid receptors in the enhancement of clonidine-induced analgesia by sulfisoxazole

Clonidine, an α2-adrenergic agonist, has been demonstrated to produce significant analgesia and potentiate morphine analgesia. Endothelin (ETA) receptor antagonists have also been found to potentiate the antinociceptive response to morphine. Clonidine and ET have been reported to have cardiovascular interactions involving the sympathetic nervous system, but it is not known whether ETA receptor antagonist affects clonidine analgesia. This study examined the influence of sulfisoxazole (ETA receptor antagonist) on clonidine analgesia. Male Swiss Webster mice were used to determine antinociceptive response of drugs by measuring tail-flick latency. The effect of clonidine (0.3, 1.0, and 3.0 mg/kg, i.p.) alone or in combination with sulfisoxazole (25, 75, and 225 mg/kg, p.o.) on analgesia and body temperature was determined. Clonidine produced a dose-dependent analgesia and hypothermia. Sulfisoxazole (25, 75, and 225 mg/kg), when administered with clonidine (0.3 mg/kg), significantly potentiated (31% increase in area under the curve (AUC)) the analgesic effect of clonidine. Yohimbine (α2-adrenergic receptor antagonist) did not affect analgesic effect of clonidine plus sulfisoxazole. Idazoxan (I1-imidazoline and α2-adrenergic receptor antagonist) reduced (47% decrease in AUC) the analgesic effect of clonidine plus sulfisoxazole. Treatment with naloxone reduced (46% decrease in AUC) the analgesic effect of clonidine plus sulfisoxazole. The effect of another ETA receptor antagonist, BMS-182874 (2, 10, and 50 µg, i.c.v.) was studied, and it was found that the dose of 10 µg significantly potentiated (26% increase in AUC) the analgesic effect of clonidine. These results indicate that sulfisoxazole, an ETA receptor antagonist, potentiates the analgesic effect of clonidine, which could be mediated through I1-imidazoline receptors and opioid receptors.

The addition of fentanyl to 1.5 mg/ml ropivacaine has no advantage for paediatric epidural analgesia

BACKGROUND

Epidural opioids are frequently combined with local anaesthetics for an additive antinociceptive effect. We investigated the efficacy of epidural fentanyl to 1.25 or 1.5 mg/ml ropivacaine for post-operative epidural analgesia in children.

METHODS

One hundred and eight children undergoing hypospadias repair were randomized to receive 1.25 mg/ml ropivacaine (R1.25 group), 1.25 mg/ml ropivacaine with 0.2 mcg/kg/h of fentanyl (R1.25F group), 1.5 mg/ml ropivacaine (R1.5 group) or 1.5 mg/ml ropivacaine with 0.2 mcg/kg/h of fentanyl (R1.5F group) for post-operative epidural analgesia. The epidural catheter was threaded caudally through the L4-5 interspace. The face, legs, activity, cry, consolability (FLACC) score was assessed at every hour and at FLACC score >4, an epidural bolus of 0.5 ml/kg of ropivacaine 1.5 mg/ml was given as the rescue analgesia. The incidence of side effects such as hypoxia, sedation, pruritus, nausea and/or vomiting was recorded.

RESULTS

The need for rescue analgesia was higher in the R1.25 group compared with that in the other three groups (all P<0.05). The incidence of side effects was higher in the R1.5F group compared with that in the R1.25 and R1.5 groups (both P=0.010).

CONCLUSION

The addition of 0.2 mcg/kg/h fentanyl to 1.5 mg/ml ropivacaine increased the incidence of side effects without improvement of analgesia in infants and children undergoing hypospadias repair. The use of plain 1.25 mg/ml ropivacaine increased the need for rescue analgesia and this could be compensated by addition of fentanyl.

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.

Dose-response study of intrathecal fentanyl added to bupivacaine in infants undergoing lower abdominal and urologic surgery

BACKGROUND

Intrathecal (IT) adjuncts often are used to enhance the duration of spinal bupivacaine. Fentanyl is a spinal analgesic that could be a useful adjunct, and enhances the duration and quality of sensory block in adult surgical and obstetric population. However, no data exist to assess the dose-response characteristics of IT fentanyl when added to bupivacaine in infants.

METHODS

Fifty-eight infants undergoing lower abdominal and urologic procedures were randomized into four groups to receive plain 0.5% hyperbaric bupivacaine F0 (<5 kg = 0.5 mg.kg(-1); 5-10 kg = 0.4 mg.kg(-1)). Groups F0.25, F0.5, and F1 groups received bupivacaine added with 0.25, 0.5, and 1 mug.kg(-1) of fentanyl, respectively. Duration of spinal anesthesia (SA) as assessed by the recovery of hip flexion in the postoperative period was the primary variable analyzed. In addition, the duration of analgesia in the postoperative period, rescue postoperative analgesic requirements and hemodynamic changes were recorded.

RESULTS

Fifty-six infants were studied. The four groups were similar for age, weight, duration of surgery, onset of sensory, motor block, and the highest level of analgesia attained. The addition of 1 mug.kg(-1) fentanyl (F1) significantly increased the duration of SA (74.27 +/- 6.1 min) compared to the control group (51.21 +/- 5.2 min) (P = 0.001). Postoperative pain-free interval was prolonged (P = 0.004) and significantly less rescue analgesics were required after 1 mug.kg(-1) IT fentanyl (P = 0.032). These parameters did not show any significant difference among groups F0, F0.25, and F0.5.

CONCLUSIONS

The addition of 1 mug.kg(-1) IT fentanyl to spinal bupivacaine prolonged the duration of spinal block in infants undergoing lower abdominal and urologic procedures.

A Comparison of Single-Dose Caudal Clonidine, Morphine, or Hydromorphone Combined with Ropivacaine in Pediatric Patients Undergoing Ureteral Reimplantation

BACKGROUND

Caudal blockade is a common technique for pediatric postoperative analgesia. While safe and effective, caudal opioids are associated with troublesome side effects. Caudal clonidine may offer significant analgesic benefits. We prospectively compared the analgesic, side effect, and rehabilitation profiles of caudal clonidine, hydromorphone, or morphine in a group of 60 pediatric patients undergoing ureteral reimplantation.

METHODS

Patients aged 6 mo to 6 yr were evenly and randomly enrolled in a double-blind manner. Patients received a single caudal dose of 2 mcg/kg of clonidine, 10 mcg/kg of hydromorphone, or 50 mcg/kg of morphine, combined with 1.0 mL/kg of 0.2% ropivacaine with epinephrine. After sevoflurane in oxygen/air anesthesia, all subjects received proxy nurse-controlled analgesia with morphine. Postoperative pain intensity, use of IV morphine, and side effects were assessed during the first 24 h. Oral intake and discharge home were recorded.

RESULTS

Caudal clonidine resulted in less postoperative nausea and vomiting (P = 0.01) and pruritus (P = 0.007) than did caudal hydromorphone or caudal morphine. Caudal morphine produced more sustained initial analgesia than did caudal clonidine (P = 0.02). No difference was observed in pain scores, total morphine use, time to first oral intake or discharge home. No postoperative respiratory depression, excessive sedation, hypotension, or bradycardia was identified.

CONCLUSIONS

Although caudal morphine may result in more sustained initial analgesia, caudal clonidine combined with nurse-controlled analgesia appears to provide comparable analgesia with fewer side effects. Based on these results, the use of caudal clonidine may be superior to caudal opioids after pediatric ureteral reimplantation.

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

BACKGROUND

The effect of clonidine on the duration of sensory blockade after peripheral nerve blockade is controversial. We evaluated the effects of clonidine on the duration of sensory and motor block and analgesia time in children who underwent a variety of peripheral nerve blocks.

METHODS

We reviewed the regional anesthesia database that contains data on children who underwent an infraclavicular, lumbar plexus, femoral, fascia iliaca or sciatic nerve block for postoperative analgesia at The Children's Hospital of Philadelphia between October 2002 and December 2005. Patients were prospectively followed after the nerve block.

RESULTS

Two hundred fifteen patients (47%) received either bupivacaine or ropivacaine local anesthetic (LA) and 220 (53%) a combination of local anesthetic and clonidine (LAC). The duration of sensory block was significantly longer in the LAC (17.2 +/- 5 h) compared with that in the LA group (13.2 +/- 5 h) (P = 0.0001). The increase in duration was independent from the type of peripheral nerve block, local anesthetic used and operation performed. The motor block duration was significantly longer in the LAC group (9.6 +/- 5 vs 4.3 +/- 4 h, P = 0.014). Two patients in the LAC and one in the LA group experience prolonged numbness (max 72 h). No paresthesia or dysesthesia was observed.

CONCLUSION

The addition of clonidine to bupivacaine and ropivacaine can extend sensory block by a few hours, and increase the incidence of motor blocks.

Could adding magnesium as adjuvant to ropivacaine in caudal anaesthesia improve postoperative pain control?

Recently, most studies reported magnesium as a N-methyl-D-aspartate receptor antagonist and its analgesic and perioperative anaesthetic effects have been discussed with central desensitization pathway. We investigated the effects of caudal ropivacaine plus magnesium and compared with ropivacaine alone on postoperative analgesia requirements. After hospital ethic committee's consent, 60 patients (ASA I-II, 2-10 years old) who had lower abdominal or penoscrotal surgery were enrolled in the study. After general anaesthesia induction, caudal blockage was applied. Patients were randomly assigned in two groups. Ropivacaine 0.25% was administered to Group R (n=37), ropivacaine 0.25% plus 50 mg magnesium to Group RM (n=23) in 0.5 ml kg-1 volume. Postoperative analgesia level was recorded at 15 min and 1, 2, 3, 4, 6 h by using Paediatric Objective Pain Scale (POPS) and The Children's Hospital of Eastern Ontoria Pain Scale (CHEOPS). Postoperative motor blocks were evaluated with Modified Bromage Motor Block Scale. According to demographic characteristics, there were no significant differences between the two groups (P>0.05). POPS, CHEOPS, Bromage Motor Scales, analgesia duration and adverse effects were similar in Group R and Group RM. It has been shown that addition of magnesium as an adjuvant agent to local anaesthetics for caudal analgesia has no effect on postoperative pain and analgesic need.

Management of the newborn infant affected by maternal opiates and other drugs of dependency

Illicit drug use during pregnancy is common and probably underestimated in the majority of published studies. The infant exposed to opiates or other drugs of dependency during intrauterine development is at risk for post-natal withdrawal as well as to long-term problems that are associated with drug-effects and often, adverse social circumstances. This article examines the early management of the infant and mother for detection and monitoring of drug-exposure, pharmacological intervention for withdrawal and the management of associated, particularly infective and psychosocial, problems. Practical concerns surrounding these issues are discussed and further research on psychosocial intervention to improve long-term outcome are much needed.

A prospective, double-blind, randomized trial of caudal block using ropivacaine 0.2% with or without fentanyl 1 microg kg-1 in children

BACKGROUND

It has been reported that ropivacaine produces vasoconstriction in contrast to vasodilation produced by bupivacaine. It is possible that additives to ropivacaine can provide further analgesic advantages compared with bupivacaine. We thus evaluated whether the addition of fentanyl to ropivacaine prolonged the duration of analgesia after a single shot caudal block.

METHODS

A total of 36 children undergoing surgical procedures below the umbilicus were randomly allocated to one of two groups: Group F received ropivacaine 0.2%, 1 ml kg(-1) with fentanyl 1 microg kg(-1) and Group S received ropivacaine 0.2%, 1 ml kg(-1) with saline. The analgesic effect of the caudal block was evaluated using the Children's Hospital of Eastern Ontario Pain Scale (CHEOPS) and sedation was assessed using the Steward score at 30 min after extubation and at 1, 2, 4, 6, 12 and 24 h. The first analgesic requirement time and side-effects in a 24 h period were also recorded.

RESULTS

There were no differences in characteristics between the groups. The end-tidal concentration of sevoflurane at extubation in Group F was significantly lower than in Group S. However, there was no significant difference in time from discontinuation of the volatile anaesthetics to tracheal extubation. No statistical differences were found in the CHEOPS and Steward score, and the time to first analgesia. The incidence of postoperative vomiting was not significantly different.

CONCLUSION

We found that the addition of fentanyl 1 mug kg(-1) to ropivacaine 0.2% for caudal analgesia provides no further analgesic advantages over ropivacaine 0.2% alone.

Analgesia and local anesthesia during invasive procedures in the neonate

BACKGROUND

Preterm and full-term neonates admitted to the neonatal intensive care unit or elsewhere in the hospital are routinely subjected to invasive procedures that can cause acute pain. Despite published data on the complex behavioral, physiologic, and biochemical responses of these neonates and the detrimental short- and long-term clinical outcomes of exposure to repetitive pain, clinical use of pain-control measures in neonates undergoing invasive procedures remains sporadic and suboptimal. As part of the Newborn Drug Development Initiative, the US Food and Drug Administration and the National Institute of Child Health and Human Development invited a group of international experts to form the Neonatal Pain Control Group to review the therapeutic options for pain management associated with the most commonly performed invasive procedures in neonates and to identify research priorities in this area.

OBJECTIVE

The goal of this article was to review and synthesize the published clinical evidence for the management of pain caused by invasive procedures in preterm and full-term neonates.

METHODS

Clinical studies examining various therapies for procedural pain in neonates were identified by searches of MEDLINE (1980-2004), the Cochrane Controlled Trials Register (The Cochrane Library, Issue 1, 2004), the reference lists of review articles, and personal files. The search terms included specific drug names, infant-newborn, infant-preterm, and pain, using the explode function for each key word. The English-language literature was reviewed, and case reports and small case series were discarded.

RESULTS

The most commonly performed invasive procedures in neonates included heel lancing, venipuncture, IV or arterial cannulation, chest tube placement, tracheal intubation or suctioning, lumbar puncture, circumcision, and SC or IM injection. Various drug classes were examined critically, including opioid analgesics, sedative/hypnotic drugs, nonsteroidal anti-inflammatory drugs and acetaminophen, injectable and topical local anesthetics, and sucrose. Research considerations related to each drug category were identified, potential obstacles to the systematic study of these drugs were discussed, and current gaps in knowledge were enumerated to define future research needs. Discussions relating to the optimal design for and ethical constraints on the study of neonatal pain will be published separately. Well-designed clinical trials investigating currently available and new therapies for acute pain in neonates will provide the scientific framework for effective pain management in neonates undergoing invasive procedures.

Anesthesia and analgesia during and after surgery in neonates

BACKGROUND

Historically, the use of anesthetics and analgesics in neonates and infants has been based on extrapolations from studies performed in adults and older children. Over the past 20 years, there has been a growing body of research on the clinical pharmacology and clinical outcomes of these agents in neonates and infants.

OBJECTIVE

This article summarizes clinical pharmacology and clinical outcomes studies of opioids, opioid antagonists, sedative-hypnotics, nonsteroidal anti-inflammatory drugs and acetaminophen, and local anesthetics in neonates and infants to highlight gaps in the available knowledge, review some concerns about study design, and identify drugs that should receive high priority for future study.

METHODS

Relevant studies were identified through a search of MEDLINE and a review of textbooks, conference proceedings, and abstracts. The available literature was subjected to expert committee-based review.

CONCLUSIONS

There is a growing body of information on analgesic and anesthetic pharmacokinetics, pharmacodynamics, and clinical outcomes in neonates and infants, permitting safe and effective use in some clinical settings. Major gaps in knowledge persist, however. Future research may involve a combination of clinical trials and preclinical studies in suitable infant animal surrogate models.

Clonidine addition prolongs the duration of caudal analgesia

BACKGROUND

In this study, using a dose-ranging design, we examined the effects of clonidine with 0.125% bupivacaine on the duration of post-operative analgesia in caudal anaesthesia in children.

METHODS

We conducted a controlled, prospective study of clonidine in caudal anaesthesia in 60 children, aged 1-10 years, undergoing elective inguinal hernia repair. Induction and maintenance of anaesthesia were performed by inhalation of sevoflurane and nitrous oxide. The children were randomized in a double-blind fashion to four groups, and were given a caudal anaesthetic with either 0.125% plain isobaric bupivacaine (1 ml/kg) or bupivacaine plus 1, 1.5 or 2 microg/kg of clonidine. The blood pressure and heart rate were recorded peri-operatively. Analgesia was evaluated by the modified Children's Hospital of Eastern Ontario Pain Scale (mCHEOPS) or a visual analogue scale (VAS). Paracetamol was given when the mCHEOPS score was greater than five or when the VAS score was greater than 30 mm. The monitoring of scores for pain, haemodynamic changes and post-operative nausea and vomiting was performed by nurses blind to the study allocation.

RESULTS

The duration of analgesia was found to be significantly longer in the group given bupivacaine plus 2 microg/kg of clonidine (median, 650 min; range, 300-900 min). Peri-operative hypotension and bradycardia, post-operative respiratory depression and motor block were not recorded in any patient.

CONCLUSIONS

The addition of clonidine to 0.125% bupivacaine prolongs the duration of post-operative analgesia without any respiratory or haemodynamic side-effects.

Pediatric acute pain management

Children are benefiting from the advances made in developmental neurobiology and analgesic pharmacology over the past few decades. Heightened public awareness and increased political pressure from external regulatory agencies are helping to maintain the momentum in improving pediatric pain management. As a result, methods of assessing and managing children's pain are being refined, and new modalities of pain relief are being explored. This review summarizes selected current topics in pediatric acute pain management, with the major emphasis on acute postoperative pain management.

Caudal anesthesia for vascular access procedures in two extremely small premature neonates

With advances in neonatology, there is an increasing need for central vascular access in extremely small (<1,000 g) premature infants. Although the use of peripherally inserted central venous lines have become common practice, surgeons still frequently perform central venous line placements via cut-down in difficult access patients. The advantages of general anesthesia for vascular access procedures are obvious for optimal pain control and ideal operative exposure; however, extremely premature infants are at significant risk for prolonged endotracheal intubation with postoperative apneas. We report two cases where regional caudal anesthesia with bupivacaine and clonidine without intubation was successfully utilized at bedside during central venous line placements in premature infants weighing <600 g. The operative field was ideal with adequate motor and sensory block with caudal anesthesia and both infants received only oxygen by nasal cannula.

The addition of clonidine 2 microg.kg-1 does not enhance the postoperative analgesia of a caudal block using 0.125% bupivacaine and epinephrine 1:200,000 in children: a prospective, double-blind, randomized study

BACKGROUND

In this prospective, randomized, double-blind study, we compared the efficacy of 0.125% bupivacaine and epinephrine 1:200,000 with and without clonidine 2 microg.kg-1 for 'single shot' pediatric caudal analgesia.

METHODS

Thirty ASA I and II children, ages 2-8 years, undergoing outpatient surgical procedures below the umbilicus received 1 ml.kg-1 0.125% bupivacaine with fresh epinephrine 1:200,000 and clonidine 2 microg.kg-1 (group-C) or 1 ml.kg-1 0.125 % bupivacaine with epinephrine 1:200 000 (group-NC). All patients received a standardized general anesthetic (induction with 67% N2O in O2 and sevoflurane followed by isoflurane maintenance). Primary outcome measures were time to first rescue analgesic and number of patients requiring rescue analgesic at 4, 6, 8, 12, and 24 h after caudal placement. Secondary outcome measures included: extubation times, Objective Pain Scale (OPS) scores, sedation scores, time in postanesthesia care unit (PACU), discharge time, number of analgesic doses given in 24 h following caudal blockade, and adverse effects (vomiting, hypotension, and bradycardia).

RESULTS

There were no differences in demographics, investigated parameters, or adverse effects between groups.

CONCLUSIONS

We found that the addition of clonidine 2 microg.kg-1 to 0.125% bupivacaine with fresh epinephrine 1:200,000 for caudal analgesia did not significantly delay the time to first rescue analgesic or decrease the overall need for rescue analgesics in children 2-8 years undergoing surgical procedures below the umbilicus.

Therapy of the neonatal abstinence syndrome with tincture of opium or morphine drops

BACKGROUND

Treating opioid-addicted women with methadone in pregnancy increased the number of newborns suffering from neonatal abstinence syndrome (NAS). High-pitch crying, insomnia, tremor, myoclonic jerks, vomiting, diarrhoea and poor weight gain were reported symptoms, which were evaluated using the Finnegan (F)-score. Earlier phenobarbital or paregoric had been used to suppress symptoms. We surveyed the administration of pure mu-agonist morphine (MO) in comparison to the alcoholic opioid mixture in tincture of opium (TO). Thirty-three newborns were included in the survey, after informed consent by their parents.

RESULTS

NAS started 3-5 days after delivery and lasted for 27 or 30 days (mean) in the TO and MO groups, respectively. In either of the tested parameters, we found no significant differences between the two groups (2P < 0.05). The maximum F-score was similar in both groups, but the dose to suppress NAS was higher in the MO group (0.6-0.5 mg/day; total dose 61.6-42.7 mg of morphine). The duration of the therapy was longer in the MO than in the TO group (37.5-32.4 days). On the other hand the weight gain was better in the MO group than in the TO group (25-19 g/day), but was reduced in both groups compared with healthy newborns.

CONCLUSIONS

Morphine is suitable to treat NAS in a similar manner as tincture of opium, but avoids unwanted effects of the alcoholic extracts with various alkaloids in the tincture of opium and allows better weight gain of the newborns.