Prospective evaluation of complications of dorsal penile nerve block for neonatal circumcision

OBJECTIVE: To evaluate the complications of the dorsal penile nerve block (DPNB) when used for routine neonatal circumcisions. METHODS: All male newborns born in a community hospital between November 1, 1989 and August 31, 1990, and circumcised after DPNB were evaluated. Questionnaires were completed at the time of hospital discharge and at a health supervision visit 2 weeks later. RESULTS: Questionnaires were returned for 491 (85%) eligible patients. The only complication of DPNB found was bruising at the site of injection in 54 patients (11%). All bruising had resolved by the 2-week visit, and none was thought to have any clinical significance. CONCLUSION: DPNB is a safe method of decreasing the pain and stress of neonatal circumcision.     

A blinded, randomized, paired, placebo-controlled trial of 20-minute EMLA cream to reduce the pain of peripheral i.v. cannulation in the ED

A eutectic mixture of local anesthetics (EMLA) in cream form has been used as a topical anesthetic to reduce the pain of procedures penetrating the skin. It is generally applied for 45 to 60 minutes before the painful procedure. The purpose of this study was to determine whether a 20-minute application of EMLA is useful in reducing the pain of routine peripheral intravenous cannulation in the emergency department (ED). A blinded, randomized, placebo-controlled, paired trial compared the pain of intravenous cannulation in both hands of study subjects: one hand was treated with 20-minute EMLA cream and the other hand was treated with 20-minute placebo cream. Forty subjects identified the more painful hand and scored pain measurements of each hand using a 10-cm visual analog scale. These data failed to demonstrate any significant benefit of EMLA compared with placebo. EMLA is not useful for intravenous cannulation when used for 20-minute application times. There may be more effective and less costly ways of reducing the pain of intravenous cannulation that patients would prefer.     

Alleviation of the pain of venepuncture in neonates

A recent study has shown venepuncture to be more effective and less painful than heel-lancing when a single blood test is performed in neonates [Larsson, Pediatrics (in press)]. The aim of the present study was to investigate the value of EMLA applied on the dorsum of the hand when sampling blood in neonates. METHODS: This was a controlled randomized and double-blinded study. One hundred and twenty neonates were randomly allocated to two groups, EMLA or placebo. Five hundred milligrams (0.5 ml) of EMLA or placebo was placed on the dorsum of the hand, covered with an occlusive dressing, and left in place for 60 minutes. For venepuncture, a needle measuring 0.9 x 40 mm was used. The two groups were also compared as regards the total time needed to complete the PKU test and the number of skin punctures required. The facial reaction was videotaped and later analysed by two blinded observers using the Neonatal Facial Coding System (NFCS). RESULTS: No side effects occurred, except for a temporary blanching or redness of the skin, which disappeared within minutes. Nociceptive response: After skin puncture, the NFCS scores were significantly lower in the EMLA group than in the placebo group (median 287 and 374, respectively). After the first skin puncture, a cry was recorded in 35/55 cases (64%) in the EMLA group and in 38/56 cases (68%) in the placebo group, this difference was not significant. The duration of the first cry was significantly shorter in the EMLA than in the placebo group (median 12 and 31 s, respectively). CONCLUSION: In comparison with a placebo, EMLA significantly reduces the pain caused by venepuncture on the dorsum of the hand and does not complicate puncture of the vein.     

Magnetic resonance imaging of epilepsy in multiple sclerosis: a case control study. Implications for treatment trials with 4-aminopyridine

A statistically significant (p = 0.049) increase in methemoglobin (MetHb), which did not exceed normal values, was noted 8 h after application of 1 g of EMLA (Eutectic Mixture of Local Anesthetics) to the foreskin of 10 normal newborns to reduce pain associated with circumcision. The highest MetHb concentration observed was 3 g/l (toxic > 50 g/l). No infant showed clinical signs of methemoglobinemia. We conclude that EMLA is safe to use as a local anesthetic in term neonates.     

Ocular toxicity following topical application of anesthetic cream to the eyelid skin

BACKGROUND AND OBJECTIVE: The use of topical anesthetic cream in the periorbital region may be of clinical value. The potential for toxic effects from such use has not been studied in a controlled manner. This study was performed to evaluate the potential ocular toxicity of anesthetic cream topically applied to the eyelid in an animal model. MATERIALS AND METHODS: Ten rabbits underwent periorbital eutectic mixture of local anesthetics (EMLA) (2.5 percent lidocaine and 2.5 percent prilocaine) application and were observed for evidence of gross or microscopic ocular toxicity. Baseline external and anterior segment examinations were performed, including biomicroscopy and fluorescein staining, after which a standard quantity of EMLA cream (0.75 g) was applied along the upper eyelid and covered with an occlusive dressing. After 1 hour of treatment, the eyelid and anterior segment were examined for evidence of adverse reaction. The eyelids were excised and examined histopathologically. RESULTS: No significant adverse effects were noted on external lid and anterior segment examination. The histopathologic findings were within normal limits. CONCLUSIONS: This study suggests that external application of EMLA cream to the eyelid does not induce local toxicity in the rabbit model. The external application of EMLA cream may be safe in the periorbital region.     

Randomized clinical trial of local anesthetic versus a combination of local anesthetic with self-hypnosis in the management of pediatric procedure-related pain.

A prospective controlled trial was conducted to compare the efficacy of an analgesic cream (eutectic mixture of local anesthetics, or EMLA) with a combination of EMLA with hypnosis in the relief of lumbar puncture-induced pain and anxiety in 45 pediatric cancer patients (age 6-16 years). The study also explored whether young patients can be taught and can use hypnosis independently as well as whether the therapeutic benefit depends on hypnotizability. Patients were randomized to 1 of 3 groups: local anesthetic, local anesthetic plus hypnosis, and local anesthetic plus attention. Results confirmed that patients in the local anesthetic plus hypnosis group reported less anticipatory anxiety and less procedure-related pain and anxiety and that they were rated as demonstrating less behavioral distress during the procedure. The level of hypnotizability was significantly associated with the magnitude of treatment benefit, and this benefit was maintained when patients used hypnosis independently. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Regional deposition and retention of particles in shallow, inhaled boluses: effect of lung volume

We evaluated the effects of volatile anesthetics on T-type calcium current (ICa,T) present in four different cell types using the whole cell version of the patch clamp technique. In dorsal root ganglion neurons and in two neuroendocrine cells--adrenal glomerulosa cells (AG) and thyroid C-cells--ICa,T was reversibly decreased by volatile anesthetics at clinically relevant concentrations, with isoflurane and enflurane being more potent that halothane. In AG cells, the most sensitive cell type tested, ICa,T was reduced 47%+/-4% (n = 6) by isoflurane (0.7 mM) and 56%+/-2% (n = 5) by enflurane (1.2 mM), but by only 24%+/-1% (n = 5; P < 0.05) by halothane (0.7 mM). Isoflurane caused a significant increase in the rate of deactivation of ICa,T in AG cells. In ventricular myocytes, however, ICa,T was much less sensitive to both isoflurane and halothane. The differential sensitivity of ICa,T in various cell types to the anesthetics may reflect differences in the channels expressed in these tissues or differences in the cellular intermediates involved in anesthetic action. Depression of ICa,T in neuronal cells may contribute to anesthetic action through decreases in cellular excitability. IMPLICATIONS: Using the patch clamp technique, we showed that T-type calcium channels, which promote cellular excitability, are inhibited by volatile anesthetics in neuronal and neuroendocrine cells, but not in ventricular myocytes. Inhibition of neuronal T-type channels may contribute to the mechanism of action of volatile anesthetics.     

Patients treated by cardiologists have a lower in-hospital mortality for acute myocardial infarction

Local anesthetics suppress excitability by interfering with ion channel function. Ensheathment of peripheral nerve fibers, however, impedes diffusion of drugs to the ion channels and may influence the evaluation of local anesthetic potencies. Investigating ion channels in excised membrane patches avoids these diffusion barriers. We investigated the effect of local anesthetics with voltage-dependent Na+ and K+ channels in enzymatically dissociated sciatic nerve fibers of Xenopus laevis using the patch clamp method. The outside-out configuration was chosen to apply drugs to the external face of the membrane. Local anesthetics reversibly blocked the transient Na+ inward current, as well as the steady-state K+ outward current. Half-maximal tonic inhibiting concentrations (IC50), as obtained from concentration-effect curves for Na+ current block were: tetracaine 0.7 microM, etidocaine 18 microM, bupivacaine 27 microM, procaine 60 microM, mepivacaine 149 microM, and lidocaine 204 microM. The values for voltage-dependent K+ current block were: bupivacaine 92 microM, etidocaine 176 microM, tetracaine 946 microM, lidocaine 1118 microM, mepivacaine 2305 microM, and procaine 6302 microM. Correlation of potencies with octanol:buffer partition coefficients (logP0) revealed that ester-bound local anesthetics were more potent in blocking Na+ channels than amide drugs. Within these groups, lipophilicity governed local anesthetic potency. We conclude that local anesthetic action on peripheral nerve ion channels is mediated via lipophilic drug-channel interactions. IMPLICATIONS: Half-maximal blocking concentrations of commonly used local anesthetics for Na+ and K+ channel block were determined on small membrane patches of peripheral nerve fibers. Because drugs can directly diffuse to the ion channel in this model, these data result from direct interactions of the drugs with ion channels.     

Effect of topical anesthetic use on initial patient satisfaction and overall success with rigid gas permeable contact lenses

BACKGROUND: Rigid gas permeable (RGP) contact lenses have numerous benefits; however, RGP lens use is not increasing in the United States. An important factor for this trend has been initial comfort. Studies have demonstrated that how RGPs are presented to patients, in addition to lens design, can play an important role in the initial comfort process. Another important factor could be the use of a topical anesthetic during the fitting and dispensing visits. The purpose of this study was to use a multicenter format to determine if topical anesthetic use increased the likelihood of patient satisfaction and success. METHODS: A total of 80 subjects, with no previous rigid lens wear experience, was entered into this 1-month study, including 20 subjects from each of 4 institutions. Subjects were randomly divided into the following two groups: (A) anesthetic or (B) placebo, with the former group receiving one drop of a topical anesthetic before lens insertion at both the diagnostic fitting and dispensing visits, whereas the latter group received a placebo. Subjects completed a questionnaire on their perception of rigid lens wear both immediately before fitting and at the 1-month visit. After diagnostic fitting with rigid lenses, subjects completed an adaptation questionnaire after 15 min, 1 week, 2 weeks, and 1 month of lens wear. RESULTS: Seventy of the 80 subjects completed the study and, of the 10 subjects who discontinued, 8 were in the placebo group. In all categories evaluated, the anesthetic group experienced a more optimum adaptation experience at each visit vs. the placebo group. Specifically, overall comfort was rated significantly higher at both dispensing and 2 weeks. In addition, the anesthetic group exhibited significantly greater overall satisfaction with rigid lens wear at 2 and 4 weeks. Also, the anesthetic group perceived their adaptation, sensitivity, and adaptation time to be significantly better at the 1-month visit. There was no significant difference in corneal staining between these two groups at each visit, with the exception of a greater amount of staining in the central quadrant for the placebo group at the 1-month visit. CONCLUSIONS: The use of a topical anesthetic at the fitting and dispensing visits for first-time wearers of RGP lenses resulted in significantly fewer dropouts, improved initial comfort, an enhanced perception of the adaptation process, and greater overall satisfaction after 1 month of lens wear as compared to the use of a nonanesthetizing placebo at those visits. This result, in combination with both presenting RGP lenses in a nonthreatening manner and optimizing the lens design and fitting relationship, should result in a positive adaptation process and successful wear of RGP contact lenses.     

Studies of drug delivery systems for a therapeutic agent used in osteoporosis. II. Enhanced absorption of elcatonin from nasal mucosa in rabbits

EMLA cream 5% (a eutectic mixture of lidocaine and prilocaine) is a topical anaesthetic that has become widely used to minimize pain from venipuncture in children. It has not, however, been recommended in neonates owing to the potential risk of methaemoglobinaemia induced by prilocaine. The aim of this study was to establish the safety of 1 g EMLA cream 5% used on intact skin in term neonates. Forty-seven neonates, aged 0-3 months, with a postconceptual age of > or = 37 weeks and a body weight between 2.8 and 5.7 kg, were included in a double-blind, randomized, placebo-controlled study. After baseline observations a total dose of 1.0 g EMLA/placebo was applied to two sites (0.5 g site(-1)) for 60-70 min. Venous methaemoglobin (metHb) levels were determined in each patient at baseline and at three randomly assigned times, 0.5-18 h after application. Following application of the cream, the mean metHb levels were 1.17% (range 0.50-2.53) in the EMLA group and 0.96% (range 0.50-1.53) in the placebo group. The metHb concentrations were significantly higher in the EMLA group in the intervals from 3.5 to 13 h after application than in the placebo group, but were well below potentially harmful levels. Based on these results, a 1-h application of 1 g EMLA cream is safe when used on the intact skin of term neonates below 3 months of age.     

Comparison of iontophoresis of lidocaine with a eutectic mixture of lidocaine and prilocaine (EMLA) for topically administered local anesthesia

BACKGROUND: Almost all dermatologic surgery is accomplished using local anesthesia. To make our patients more comfortable, there is a constant search for less painful methods of administering anesthetic agents. Topical EMLA as well as iontophoresis are both useful in this regard. OBJECTIVE: In this study we compared topical EMLA with lidocaine delivered by iontophoresis in a double-blind placebo-controlled trial. Our goal was to assess the degree of anesthesia obtained as well as the relative rapidity of onset. METHODS: A double-blind controlled study was performed on 10 healthy volunteers between 26 and 37 years of age. Three test sites were placed on each forearm. EMLA or a moisturizer control was placed on two of the three test sites on each arm. Each site was wiped free of cream and tested for sensitivity to pinprick 30 and 60 minutes after cream placement. One iontophoretic unit was placed on each forearm. Both units were saturated with anesthesia with the control unit being turned off. Sensitivity to pinprick was evaluated at the iontophoretic sites and one of the EMLA sites 30 minutes after site placement on the subject. The additional EMLA-treated site was tested in the same manner 60 minutes after placement. RESULTS: Both EMLA cream and the iontophoretic unit delivered topical anesthesia greater than the control. Significantly more anesthesia was acquired 1 hour after application of EMLA than was seen 30 minutes earlier. The iontophoretic patch-treated area provided greater anesthesia than the EMLA-treated sites evaluated 30 and 60 minutes after placement. Both modalities provided significant anesthesia when left in place for 60 minutes. CONCLUSION: Both iontophoresis of lidocaine and topical EMLA delivered significant, and sometimes complete, local anesthesia. A greater degree of anesthesia is delivered via iontophoresis after 30 minutes as compared with EMLA left on the skin for 30 or 60 minutes. Both modalities have important and unique advantages and disadvantages. Topical EMLA and iontophoretically delivered lidocaine are both valuable tools for the dermatologic surgeon.     

A comparison of topical anaesthesia and electronic nerve stimulation for reducing the pain of intra-oral injections

This paper describes a model for investigating the efficacy of different methods of alleviating the pain of intra-oral injections. The efficacies of the topical anaesthetic EMLA cream and electronic nerve stimulation as means of reducing the discomfort of palatal injections prior to the extraction of maxillary teeth were investigated using the model in one hundred patients. EMLA reduced the pain of injection compared with placebo (P < 0.05) whereas the pain reported after electronic nerve stimulation did not differ significantly from placebo. It is concluded that EMLA is useful in reducing the pain of palatal injections.     

Comparative study of distraction versus topical anesthesia for pediatric pain management during immunizations.

This study compared distraction, an anesthetic (eutectic mixture of local anesthetics [EMLA]), and typical care during pediatric immunizations. Participants were 39 4th graders receiving a 3-injection vaccination series over a 6-month period. Children displayed low distress despite reporting moderate anxiety and pain. Distraction resulted in more nurse coaching and child coping and less child distress than did EMLA or typical care on an observational measure. EMLA did not result in increased child coping or decreased distress. In fact, the nurse coached more, and trends suggested that children coped more with typical care than with EMLA. Whereas participant ratings and heart rate did not differ among conditions, all 3 conditions demonstrated improvements over time with these measures. Satisfaction ratings suggested that children preferred the treatments to typical care, whereas the nurse appreciated aspects of each of the conditions. Finally, distraction was more economical than EMLA. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Epididymitis in children: the circumcision factor?

PURPOSE: Recommendations for circumcision have significantly altered in the last several years. Studies have objectively established an increased risk of urinary tract infection in uncircumcised boys. We evaluated the relationship between epididymitis and circumcision status. MATERIALS AND METHODS: We studied the relationships among the circumcision status of 36 consecutive boys with epididymitis in a review of 128 with acute scrotal inflammation (group 1), circumcision status of 43 in whom the diagnosis of epididymitis at discharge home had been made elsewhere (group 2), New York State hospital discharge figures for circumcision in newborns (group 3) and the regional prevalence of circumcision in 200 consecutive pediatric emergency department patients at the same institution with nonurological diagnoses (group 4). RESULTS: New York State Department figures indicate that 70% of male newborns are discharged home with a hospital code for circumcision. Similarly an evaluation of 200 consecutive male patients without urological diagnoses younger than 18 years in the emergency department revealed that 131 (65%) were circumcised. Comparatively in groups 1 and 2 only 25 and 26% of patients, respectively, were circumcised. The statistical difference in circumcision status among the 4 groups was significant (p >0.0004). CONCLUSIONS: These data demonstrate with highly statistical significance that a relationship exists between epididymitis and the presence of a foreskin. We found that an intact foreskin is an important etiological factor in boys with epididymitis.     

Lucigenin as mediator of superoxide production: revisited

PURPOSE: To evaluate whether a very slow injection of local anaesthetics during dorsal penile nerve block for circumcision causes less pain than a more rapid injection. METHODS: In a prospective, double-blind, randomized study, 75 patients aged 15 to 53 yr (mean +/- SD = 22 +/- 8.4 yr) were randomized into two groups. A solution of 2% lidocaine, 1 mg.kg-1, and 0.5% bupivacaine, 0.5 mg.kg-1 without epinephrine to a maximum dose of 10 ml was injected using either a very slow rate (injection time 100 to 150 s, Group A) or a faster rate (injection time 40 to 80 s, Group B). Patients were questioned regarding pain by a physician who was blinded to the mode of therapy. Pain was rated as 1) mild (negligible), 2) moderate (non-negligible, but easily endurable), 3) intense (but endurable) and 4) total refusal to continue. RESULTS: A significant pain score difference was found between Groups A and B (median = 1 vs. 2, P = 0.0006) as well as a significant correlation between pain score and the rate of infiltration (rs = -0.394, P < 0.0001). CONCLUSIONS: Slow injection is an important factor in reducing pain during penile block.     

Regional nerve block for total knee arthroplasty

Femoral and sciatic nerve blocks have been used occasionally for unilateral total knee arthroplasty (TKA). In order to evaluate the effectiveness of this technique, combined femoral 3-in-1 and sciatic nerve blocks were performed in 20 cases of TKA, by the same surgeon. This surgeon also performed unilateral TKA under spinal anesthesia in another 20 cases. The anesthetic effectiveness of the two types of anesthesia was compared in terms of the time needed to complete the surgery, amount of intraoperative blood loss, and time interval until the first dose of analgesic. The results showed that the two types of anesthesia had comparable anesthetic effects. Ten of the 20 patients who had spinal anesthesia complained of postoperative urinary retention, while none of those who had nerve block had this complaint. Neither group experienced postpunctural headache, neurovascular damage, or drug-over-dose toxicity. We conclude that combined femoral 3-in-1 and sciatic nerve block is an effective anesthetic alternative for unilateral TKA.     

Learning about reflection

Circumcision performed using the Gomco clamp is usually quick and effective, and results in very little bleeding. However, every clinician performing circumcision occasionally has concerns or questions regarding the procedure. Some of the more common concerns regarding the use of the Gomco clamp are technique-related, including choosing the correct size of the Gomco bell and clamp for the procedure, choosing the right method of getting the foreskin properly through the hole of the Gomco base plate, and assessing how much foreskin to remove. Other concerns include poor cosmetic results, contraindications to routine circumcision, and circumcision in an infant whose mother has human immunodeficiency virus. This article reviews the technique of circumcision using the Gomco clamp and answers some of the more common questions.     

Ultrathin endoscopy in the assessment and treatment of upper and lower gastrointestinal tract strictures

BACKGROUND AND OBJECTIVES: Superior hypogastric plexus block has been used to treat cancer pain of the pelvis. METHODS: A patient with severe chronic nonmalignant penile pain after transurethral resection of the prostate underwent a single superior hypogastric plexus block with local anesthetic and steroid. The patient was also started on medications that treat neuropathic pain a few hours after the procedure was finished. RESULTS: The superior hypogastric plexus block resulted in complete pain relief immediately after the procedure. The pain relief continued at 1, 2, 4, and 8 months follow up. CONCLUSIONS: In this case of severe penile pain the superior hypogastric plexus block was useful diagnostically and therapeutically.     

Suprascapular nerve block for postoperative pain relief in arthroscopic shoulder surgery: a new modality?

Arthroscopic shoulder surgery has a 45% incidence of severe postoperative pain. Opiates and interscalene nerve blocks have a high incidence of side effects, and intraarticular local anesthetic has been shown to be ineffective when used for postoperative pain relief. The suprascapular nerve supplies 70% of the sensory nerve supply to the shoulder joint, and local anesthetic block of this nerve is effective in certain shoulder pain disorders. To determine the efficacy of a suprascapular nerve block, subcutaneous saline was compared with a suprascapular nerve block using 10mL of 0.5% bupivacaine with 1:200,000 epinephrine before general anesthesia was induced. In the immediate postoperative period, a 51% reduction in demand and a 31% reduction in consumption of morphine delivered by a patient-controlled analgesic system was demonstrated. There was more than fivefold reduction in the incidence of nausea, as well as reduced visual analog and verbal pain scores for patients who received a suprascapular nerve block. The duration of hospital stay was reduced by 24% in the suprascapular nerve block group. A 24-h phone call interview revealed a 40% reduction in analgesic consumption and a reduction in verbal pain scores at rest and on abduction. There were no complications from the suprascapular nerve block. This study demonstrates that a suprascapular nerve block for pain relief in arthroscopic shoulder surgery is an effective and safe modality of postoperative pain relief.     

Comparison of the clinical efficacy of three perivascular techniques for axillary brachial plexus block

BACKGROUND AND OBJECTIVES: This study compared the efficacy of three perivascular techniques of axillary block. METHODS: In group 1, all of the local anesthetic was injected after advancing the needle through the axillary artery (back of artery, n = 20); in group 2, after withdrawing slightly from the artery (front of artery, n = 20); and in group 3, half of the anesthetic was injected after advancing through and half after withdrawing from the axillary artery (half and half, n = 20). The local anesthetic used for the axillary block was 50 ml of 1.5% mepivacaine with epinephrine 1:200,000. RESULTS: The groups did not differ significantly in the incidence of analgesia or anesthesia expected in the median nerve distribution, where there was a significantly lower incidence of anesthesia in the back of the artery group. This group also had a slower onset of anesthesia for the median and the medial antebrachial cutaneous nerves. CONCLUSIONS: There was no significant difference in the number of patients requiring supplementation, with five patients in the back group (25%), three patients in the front group (15%), and one patient in the half and half group (5%) requiring supplementation for the surgical procedure.