The use of a topical refrigerant anesthetic to reduce injection pain in children

The efficacy of vapocoolant spray for the improved tolerance of catheter pain in emergency patients

OBJECTIVES

This study aimed to determine if dogs and cats presenting as an emergency had improved tolerance of intravenous catheterisation following the application of vapocoolant spray when compared to a saline control.

MATERIALS AND METHODS

A randomised controlled trial of client-owned dogs and cats presenting as an emergency and requiring intravenous catheterisation was performed. Patient signalment and mentation score were recorded. All animals were restrained and had their fur clipped over the catheterisation site. They were then randomly allocated to either have a swab saturated with vapocoolant spray (treatment) or a swab saturated with saline (control) applied to the clipped area before intravenous catheterisation. The procedure was video recorded and a single blinded observer reviewed the recordings and assigned reaction scores (0 to 3) at four time points (initial restraint, limb handling, swab application and skin puncture).

RESULTS

Between October 2020 and January 2021, a total of 100 patients (79 dogs, 21 cats) were enrolled, with 50 in each group. No significant difference in species, age, breed, sex or mentation score was detected between the two groups. There was no significant difference in reaction scores between the groups at any time point with the exception of a significantly increased swab application reaction score in the treatment group compared to the control group.

CLINICAL SIGNIFICANCE

The indirect application of vapocoolant spray via a swab before catheterisation does not significantly reduce the reaction of dogs and cats to intravenous catheterisation in an emergency setting.

Effect of precooling on pain during local anesthesia administration in children: a systematic review

This study was conducted to determine how precooling reduces the subjective reported pain and objective pain and to evaluate the effectiveness of precooling the injection site before administration of local anesthesia in children. Electronic databases (PubMed, Ovid SP, Cochrane Central Register of Controlled Trials) were searched for publications from 1980 to 2020. Studies were screened for titles and abstracts, followed by full-text evaluation of included reports. Six studies were included in this systematic review. The primary outcome evaluated was the pain perception or the subjective pain reported by the child receiving the injection. The secondary outcome evaluated was objective pain evaluated in each study. Among 5 studies that evaluated child reported pain scores on a visual analogue scale (VAS), 4 studies reported lower scores in the precooling group and one study reported a higher VAS score in the precooling group than in children treated with 20% benzocaine topical anesthesia. Among 6 studies that evaluated the pain reaction of children by Sound Eye Motor (SEM) score, 4 studies reported a lower SEM score in the precooling group, one study reported no significant difference between the precooling and control groups, and one study reported higher SEM scores in the precooling group than in children treated with 20% benzocaine topical anesthesia. Within the limits of this systematic review, evidence suggests that precooling the injection site with ice can be an effective adjunct to topical anesthesia in reducing both subjective and objective pain during local anesthesia administration in children.

Pharmacological interventions for reducing pain related to immunization or intramuscular injection in children: A mixed treatment comparison network meta-analysis of randomized controlled clinical trials

Various interventions were observed to reduce pain following vaccination in children. This study is a network meta-analysis comparing pharmacological interventions. Electronic databases were searched for appropriate randomized controlled clinical trials comparing active pharmacological agents to reduce pain following vaccination or intramuscular injection in neonates, infants, or children. Pain score was the primary outcome measure. Random effects model was used for generating pooled estimates. A total of 23 studies were included in the network meta-analysis. Topical eutectic mixture of local anesthetics (EMLA) significantly reduced pain scores. Crying time was also observed to be lower with vapocoolant spray and 25% sucrose and glucose solutions. Quality of the evidence was observed to be either low or very low. Topical EMLA significantly reduce pain following intramuscular injections particularly vaccination. However, due to low grade quality of the evidence, more studies are obligatory.

Improving vaccine-related pain, distress or fear in healthy children and adolescents-a systematic search of patient-focused interventions

OBJECTIVE

The WHO recently highlighted the need for research into potential interventions that can be used to mitigate pain during mass vaccinations, in addition to interventions specific for adolescents. The current review examines the literature on potential interventions that can be used during mass vaccination settings in healthy individuals between the ages of 4 and 15 years old.

METHODS

Criteria for inclusion were: 1)participants between the ages of 4-15 years, 2)interventions that were patient-focused, 3)vaccinations in healthy individuals, 4)outcome measures to include self-reported pain, fear or distress.

RESULTS

Twenty-seven articles were identified with a total of 31 interventions. Eleven interventions used injection-site specific interventions, 17 used patient-led interventions and three used a combination of both site-specific and patient-led interventions.

CONCLUSION

Interventions using coolant and vibration together, as well as a combination of site-specific and patient-led interventions, showed the most consistent effects in reducing self-reported pain, fear or distress.

Ethyl chloride spray for musculoskeletal ultrasound-guided injections: An alternative to subcutaneous injection of local anesthetic solution

Ultrasound-guided injections such as steroid injections are common procedures involving the musculoskeletal system. They are usually performed after a subcutaneous injection of local anesthetic (LA), which can be painful. In 126 consecutive patients, local anesthesia was performed using ethyl chloride spray prior to a therapeutic ultrasound-guided injection in joints, tendons, or bursae. Ninety-nine (78.5%) patients found the use of ethyl chloride spray helpful. The use of ethyl chloride spray is an effective, patient-friendly alternative to the standard injection of local aesthetic for ultrasound-guided therapeutic musculoskeletal injections with the advantage of a lower cost of $0.18 per procedure.

Clinical Comparison: Fast-Acting and Traditional Topical Dental Anesthetic

A randomized, nonblinded clinical trial compared the effectiveness of an application method of a fast-acting refrigerant topical agent to a 20% benzocaine gel topical. In a split-mouth design, right and left anterior middle superior alveolar injections (N = 30) were administered with a 27-gauge needle at least 24 hours apart with preinjection topicals. Using a cotton-tipped applicator, a refrigerant topical was applied for 5 seconds and 20% benzocaine gel for 2 minutes on opposite sides at 2 separate appointments. Subjects self-reported pain perception after each injection using a visual analog scale (VAS). The mean VAS ratings demonstrated no significant difference between the 5-second application of the refrigerant (M = 16.2, SD = 17.7) and the 2-minute application of 20% benzocaine topical gel anesthetic (M = 17.9, SD = 18.2). Fifty-seven percent of the subjects reported greater pain reduction with the refrigerant, 33% reported greater pain reduction with 20% benzocaine, and 10% reported no difference. Results suggest the described method of application of a refrigerant as an oral topical anesthetic has a faster onset and provides similar benefit in pain reduction compared with 20% benzocaine gel. The refrigerant was easy to accomplish and well received by subjects, indicating potential for routine use in dentistry.

Pharmacological and Combined Interventions to Reduce Vaccine Injection Pain in Children and Adults: Systematic Review and Meta-Analysis

BACKGROUND

This systematic review assessed the effectiveness and safety of pharmacotherapy and combined interventions for reducing vaccine injection pain in individuals across the lifespan.

DESIGN/METHODS

Electronic databases were searched for relevant randomized and quasi-randomized controlled trials. Self-reported pain and fear as well as observer-rated distress were critically important outcomes. Data were combined using standardized mean difference (SMD) or relative risk with 95% confidence intervals (CI).

RESULTS

Fifty-five studies that examined breastfeeding (which combines sweet-tasting solution, holding, and sucking), topical anesthetics, sweet-tasting solutions (sucrose, glucose), vapocoolants, oral analgesics, and combination of 2 versus 1 intervention were included. The following results report findings of analyses of critical outcomes with the largest number of participants. Compared with control, acute distress was lower for infants breastfed: (1) during vaccination (n=792): SMD -1.78 (CI, -2.35, -1.22) and (2) before vaccination (n=100): SMD -1.43 (CI, -2.14, -0.72). Compared with control/placebo, topical anesthetics showed benefit on acute distress in children (n=1424): SMD -0.91 (CI, -1.36, -0.47) and self-reported pain in adults (n=60): SMD -0.85 (CI, -1.38, -0.32). Acute and recovery distress was lower for children who received sucrose (n=2071): SMD -0.76 (CI, -1.19, -0.34) or glucose (n=818): SMD -0.69 (CI, -1.03, -0.35) compared with placebo/no treatment. Vapocoolants reduced acute pain in adults [(n=185), SMD -0.78 (CI, -1.08, -0.48)] but not children. Evidence from other needle procedures showed no benefit of acetaminophen or ibuprofen. The administration of topical anesthetics before and breastfeeding during vaccine injections showed mixed results when compared with topical anesthetics alone. There were no additive benefits of combining glucose and non-nutritive sucking (pacifier) compared with glucose or non-nutritive sucking (pacifier) alone or breastfeeding and sucrose compared with breastfeeding or sucrose alone.

CONCLUSIONS

Breastfeeding, topical anesthetics, sweet-tasting solutions, and combination of topical anesthetics and breastfeeding demonstrated evidence of benefit for reducing vaccine injection pain in infants and children. In adults, limited data demonstrate some benefit of topical anesthetics and vapocoolants.

Microcirculatory effect of topical vapocoolants

BACKGROUND

Vapocoolant sprays are commonly used to minimize pain following minor interventions such as venipuncture, shave biopsy or needle insertion. Although these sprays have been widely used in clinical practice, little is known about their effect on microcirculation or cutaneous blood flow.

OBJECTIVE

To evaluate the real-time effect of a topical vapocoolant using a well-established, rat cremaster muscle microcirculatory model, allowing direct measurement of changes in vessel diameter, capillary density and leukocyte behaviour.

METHODS

Fifty rats were divided into a control and four experimental groups: group 1: 4 s spray with vapocoolant at 18 cm distance; group 2: 10 s spray at 18 cm distance; group 3: 4 s spray at 8 cm distance; and group 4: 10 s spray at 8 cm distance. Vessel diameters, capillary density and leukocyte behaviour were monitored for 1 h thereafter. Muscle was harvested for immunohistochemistry analysis of proangiogenic markers (vascular endothelial growth factor and von Willebrand factor), leukocyte behaviour markers (E-selectin, vascular cell adhesion molecule, intercellular adhesion molecule), pimonidazole-hypoxia staining and ApopTag (Millipore, USA) staining for apoptosis. Gene expression for inflammatory markers (interleukin [IL]-1β, IL-2, IL-4, IL-6, IL-10, tumour necrosis factor-alpha and interferon-gamma) was evaluated using polymerase chain reaction and myeloperoxidase assay for inflammation was performed.

RESULTS

The use of refrigerant spray decreased vessel diameter and capillary density initially, although none of these decreases were statistically significant. Polymerase chain reaction showed no significant changes. The myeloperoxidase assay showed statistically significant increase in myeloperoxidase activity in groups 2, 3 and 4. Immunohistochemistry was negative for angiogenic and proinflammatory markers.

CONCLUSIONS

The lack of statistically significant changes in vessel diameter and inflammatory markers corroborated the safety on microcirculation.

Microcirculatory effect of topical vapocoolants

Background

Vapocoolant sprays are commonly used to minimize pain following minor interventions such as venipuncture, shave biopsy or needle insertion. Although these sprays have been widely used in clinical practice, little is known about their effect on microcirculation or cutaneous blood flow.

Objective

To evaluate the real-time effect of a topical vapocoolant using a well-established, rat cremaster muscle microcirculatory model, allowing direct measurement of changes in vessel diameter, capillary density and leukocyte behaviour.

Method

Fifty rats were divided into a control and four experimental groups: group 1: 4 s spray with vapocoolant at 18 cm distance; group 2: 10 s spray at 18 cm distance; group 3: 4 s spray at 8 cm distance; and group 4: 10 s spray at 8 cm distance. Vessel diameters, capillary density and leukocyte behaviour were monitored for 1 h thereafter. Muscle was harvested for immunohistochemistry analysis of proangiogenic markers (vascular endothelial growth factor and von Willebrand factor), leukocyte behaviour markers (E-selectin, vascular cell adhesion molecule, intercellular adhesion molecule), pimonidazole-hypoxia staining and ApopTag (Millipore, USA) staining for apoptosis. Gene expression for inflammatory markers (interleukin [IL]-1β, IL-2, IL-4, IL-6, IL-10, tumour necrosis factor-alpha and interferon-gamma) was evaluated using polymerase chain reaction and myeloperoxidase assay for inflammation was performed.

Result

The use of refrigerant spray decreased vessel diameter and capillary density initially, although none of these decreases were statistically significant. Polymerase chain reaction showed no significant changes. The myeloperoxidase assay showed statistically significant increase in myeloperoxidase activity in groups 2, 3 and 4. Immunohistochemistry was negative for angiogenic and proinflammatory markers.

Conclusions

The lack of statistically significant changes in vessel diameter and inflammatory markers corroborated the safety on microcirculation.

Evaluation of methods to relieve parental perceptions of vaccine-associated pain and anxiety in children: a pilot study

INTRODUCTION

The pain and anxiety associated with vaccination is a significant reason why parents are reluctant to have their children vaccinated. Distraction methods and vapocoolant sprays may be use to modify the parent's perceptions of their child's pain and anxiety, thus encouraging parents to return for the child's next vaccination.

METHODS

A convenience sample of 68 parents with children ranging in age from 2 to 12 years was selected. The parents and the child were randomly assigned to three groups: a control group, a DVD distraction group, or a vapocoolant spray group. After the child was vaccinated, parents evaluated the child's pain and anxiety.

RESULTS

No significant difference in the parents' perception of their child's pain or anxiety was found between the two treatment groups compared with the control group. Some parents expressed the desire to be able to choose the type of distraction method their child received rather than having them randomly assigned to a group.

DISCUSSION

Although quantitative results were not statistically significant in this pilot study, parents commented that the DVD distraction method seemed helpful before and/or after vaccination, but not during vaccination, and parents appreciated the distraction. Parents, however, would prefer to choose the intervention rather than being randomly assigned to a group. The effectiveness of interventions with regard to parental perceptions of pain or anxiety warrants further study.

Using cold air for reducing needle-injection pain

BACKGROUND

Pain is associated with skin injections. Reducing injection-associated pain is important especially when multiple injections are needed in difficult areas, such as the palms. We present a new safe application for cold air used in laser therapy.

OBJECTIVE

The main objectives of this study are to see whether cold air can reduce needle-injection pain and to evaluate the safety of this new application.

MATERIALS AND METHODS

Patients undergoing skin injection (n=40) were included. Assessment of pain level using visual analog scale (VAS) was done using cold air and again without cold air in the same patient. Comparison of pain scores was performed.

RESULTS

Thirty-three patients had lower VAS scores using cold air. Five patients had worse VAS scores, and two patients did not have any change in their pain score. In the group of patients where injections were made to the palms (n=5), there was even more reduction in VAS scores. There were no significant immediate or delayed side effects.

CONCLUSIONS

Cold air seems to be useful in reducing needle-injection pain in the majority of patients, especially in the palms. This procedure is safe, apart from immediate tolerable discomfort when used around the nose.

Placebo interventions for all clinical conditions

BACKGROUND

Placebo interventions are often claimed to substantially improve patient-reported and observer-reported outcomes in many clinical conditions, but most reports on effects of placebos are based on studies that have not randomised patients to placebo or no treatment. Two previous versions of this review from 2001 and 2004 found that placebo interventions in general did not have clinically important effects, but that there were possible beneficial effects on patient-reported outcomes, especially pain. Since then several relevant trials have been published.

OBJECTIVES

Our primary aims were to assess the effect of placebo interventions in general across all clinical conditions, and to investigate the effects of placebo interventions on specific clinical conditions. Our secondary aims were to assess whether the effect of placebo treatments differed for patient-reported and observer-reported outcomes, and to explore other reasons for variations in effect.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library Issue 4, 2007), MEDLINE (1966 to March 2008), EMBASE (1980 to March 2008), PsycINFO (1887 to March 2008) and Biological Abstracts (1986 to March 2008). We contacted experts on placebo research, and read references in the included trials.

SELECTION CRITERIA

We included randomised placebo trials with a no-treatment control group investigating any health problem.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trial quality and extracted data. We contacted study authors for additional information. Trials with binary data were summarised using relative risk (a value of less than 1 indicates a beneficial effect of placebo), and trials with continuous outcomes were summarised using standardised mean difference (a negative value indicates a beneficial effect of placebo).

MAIN RESULTS

Outcome data were available in 202 out of 234 included trials, investigating 60 clinical conditions. We regarded the risk of bias as low in only 16 trials (8%), five of which had binary outcomes.In 44 studies with binary outcomes (6041 patients), there was moderate heterogeneity (P < 0.001; I(2) 45%) but no clear difference in effects between small and large trials (symmetrical funnel plot). The overall pooled effect of placebo was a relative risk of 0.93 (95% confidence interval (CI) 0.88 to 0.99). The pooled relative risk for patient-reported outcomes was 0.93 (95% CI 0.86 to 1.00) and for observer-reported outcomes 0.93 (95% CI 0.85 to 1.02). We found no statistically significant effect of placebo interventions in four clinical conditions that had been investigated in three trials or more: pain, nausea, smoking, and depression, but confidence intervals were wide. The effect on pain varied considerably, even among trials with low risk of bias.In 158 trials with continuous outcomes (10,525 patients), there was moderate heterogeneity (P < 0.001; I(2) 42%), and considerable variation in effects between small and large trials (asymmetrical funnel plot). It is therefore a questionable procedure to pool all the trials, and we did so mainly as a basis for exploring causes for heterogeneity. We found an overall effect of placebo treatments, standardised mean difference (SMD) -0.23 (95% CI -0.28 to -0.17). The SMD for patient-reported outcomes was -0.26 (95% CI -0.32 to -0.19), and for observer-reported outcomes, SMD -0.13 (95% CI -0.24 to -0.02). We found an effect on pain, SMD -0.28 (95% CI -0.36 to -0.19)); nausea, SMD -0.25 (-0.46 to -0.04)), asthma (-0.35 (-0.70 to -0.01)), and phobia (SMD -0.63 (95% CI -1.17 to -0.08)). The effect on pain was very variable, also among trials with low risk of bias. Four similarly-designed acupuncture trials conducted by an overlapping group of authors reported large effects (SMD -0.68 (-0.85 to -0.50)) whereas three other pain trials reported low or no effect (SMD -0.13 (-0.28 to 0.03)). The pooled effect on nausea was small, but consistent. The effects on phobia and asthma were very uncertain due to high risk of bias. There was no statistically significant effect of placebo interventions in the seven other clinical conditions investigated in three trials or more: smoking, dementia, depression, obesity, hypertension, insomnia and anxiety, but confidence intervals were wide.Meta-regression analyses showed that larger effects of placebo interventions were associated with physical placebo interventions (e.g. sham acupuncture), patient-involved outcomes (patient-reported outcomes and observer-reported outcomes involving patient cooperation), small trials, and trials with the explicit purpose of studying placebo. Larger effects of placebo were also found in trials that did not inform patients about the possible placebo intervention.

AUTHORS' CONCLUSIONS

We did not find that placebo interventions have important clinical effects in general. However, in certain settings placebo interventions can influence patient-reported outcomes, especially pain and nausea, though it is difficult to distinguish patient-reported effects of placebo from biased reporting. The effect on pain varied, even among trials with low risk of bias, from negligible to clinically important. Variations in the effect of placebo were partly explained by variations in how trials were conducted and how patients were informed.

A randomized controlled trial of vapocoolant for pediatric immunization distress relief

OBJECTIVES

The purpose of this study was to evaluate the effectiveness of vapocoolant for preschoolers' immunization injection pain relief.

METHODS

Fifty-seven 4 to 6-year-old children were randomized into vapocoolant alone or typical care conditions. Pain was measured at the baseline and at injection via self-report, caregiver report, nurse report, and by an observational scale.

RESULTS

Self-report of pain suggested that children in the vapocoolant alone condition demonstrated stronger increases in pain from baseline to injection than children in the typical care condition. All other measures showed significant increases in pain from baseline to injection, but no other measures indicated treatment effects.

DISCUSSION

This study revealed that vapocoolant is not an effective pain management intervention for children's intramuscular injections.

Efficacy of ShotBlocker in reducing pediatric pain associated with intramuscular injections

OBJECTIVE

The aim of the study was to determine the efficacy of ShotBlocker (Bionix, Toledo, Ohio) in reducing pediatric pain with intramuscular (IM) injections.

METHODS

A prospective randomized controlled trial was conducted in children aged 2 months to 17 years who required an IM injection. Children were randomized to the no-intervention group or the ShotBlocker group. Demographic data and the number of IM injections were recorded. Perceived pain scores were obtained from nurses and caregivers using a 6-point Likert-type scale. Baker Wong Faces scale was used in children 36 months or older. Difficulty using the device was also rated by nurses on a 6-point scale.

RESULTS

One hundred sixty-five children were enrolled with 80 in the no-intervention arm and 85 in the ShotBlocker arm. The mean age of children was 45 months and 56% were male. Perceived pain scores by nurses were higher for the no-intervention group (2.6 vs 1.8, P < .001) as well as by caregivers (2.6 vs 2.1, P = .04). Children aged 36 months and older (n = 64) did not report a difference in pain scores (1.5 vs 1.3, P = .6); however, in a subgroup of children 72 months or older, pain scores trended higher in the no-intervention group (1.3 vs 0.5, P = .051). Nurse-perceived difficulty of ShotBlocker use was low 1.39 (+/-1.1).

CONCLUSIONS

Nurses and caregivers noted lower pain scores in children assigned to the ShotBlocker group. These differences were not as evident when children rated their own pain.

The effect of vapocoolant spray on pain due to intravenous cannulation in children: a randomized controlled trial

BACKGROUND

Established noninvasive pharmacologic means of alleviating pain and anxiety in children undergoing intravenous cannulation are time-consuming, and thus impractical for routine use in the emergency department. Vapocoolant sprays provide transient skin anesthesia within seconds of application. We compared the effect of a new vapocoolant spray to placebo on pain due to intravenous cannulation in children.

METHODS

In this double-blind randomized controlled trial, which we conducted between June 1 and Sept. 12, 2006, 80 children aged 6-12 years received either vapocoolant spray or placebo before cannulation. Children rated their pain using a 100-mm colour visual analogue scale. Secondary outcomes included success rate on first attempt at cannulation and pain ratings by the children's parents, nurses and child life specialists.

RESULTS

We found a modest but significant reduction in pain with the use of vapocoolant spray (mean difference 19 mm, 95% confidence interval [CI] 6-32 mm; p < 0.01). Cannulation on first attempt was more often successful with the use of vapocoolant spray (85.0%) than with placebo (62.5%) (mean difference 22.5%, 95% CI 3.2%-39.9%; p = 0.03). The number needed to treat to prevent 1 cannulation failure was 5 (95% CI 3-32). Parents (p = 0.04), nurses (p = 0.01) and child life specialists (p < 0.01) considered the children's pain to be reduced with the use of vapocoolant spray.

INTERPRETATION

The vapocoolant spray in our study quickly and effectively reduced pain due to intravenous cannulation in children and improved the success rate of cannulation. It is an important option to reduce childhood procedural pain in emergency situations, especially when time precludes traditional interventions. (http://ClinicalTrials.gov trial register no. NCT00130650.).

Pain reduction during pediatric immunizations: evidence-based review and recommendations

The pain associated with immunizations is a source of anxiety and distress for the children receiving the immunizations, their parents, and the providers who must administer them. Preparation of the child before the procedure seems to reduce anxiety and subsequent pain. The limited available data suggest that intramuscular administration of immunizations should occur in the vastus lateralis (anterolateral thigh) for children <18 months of age and in the deltoid (upper arm) for those >36 months of age. Controversy exists in site selection for 18- to 36-month-old children. A number of studies suggest that the ventrogluteal area is the most appropriate for all age groups. Longer needles are usually associated with less pain and less local reaction. During the injection, parental demeanor clearly affects the child's pain behaviors. Excessive parental reassurance, criticism, or apology seems to increase distress, whereas humor and distraction tend to decrease distress. Distraction techniques vary with the age, temperament, and interests of the child, but their efficacy is well supported in the literature. Sucrose solution instilled directly into the mouth or administered on a pacifier reduces evidence of distress reliably in children <6 months of age and should be used routinely. Although there is no perfect topical anesthetic available at this time, selective use for children who are particularly fearful or who have had negative experiences in the past is highly endorsed. Pressure at the site, applied with either a device or a finger, clearly reduces pain. Finally, in the era of multiple injections, it seems that parents prefer that multiple injections be given simultaneously, rather than sequentially, if there are enough personnel available. Immunizations are stressful for many children; until new approaches are developed, systematic use of available techniques can significantly reduce the burden of distress associated with these procedures.

Ethyl vinyl chloride vapocoolant spray fails to decrease pain associated with intravenous cannulation in children

The purpose of the study was to determine the effect of ethyl vinyl chloride vapocoolant spray on pain reported by children undergoing intravenous cannulation. A randomized, double-blinded, placebo-controlled trial was conducted on eligible children between the ages of 9 and 18 years seen in a pediatric emergency department and requiring intravenous cannulation. Informed consent was obtained, and children were randomized to receive ethyl vinyl chloride spray, isopropyl alcohol spray, or no spray (control group). Patient demographics and information pertaining to each intravenous cannulation were recorded. Children indicated the degree of pain associated with intravenous cannulation on a 100-mm visual analog scale (VAS) compared to a baseline pain score of "zero." Statistical analysis was performed by using Stata version 7. One hundred twenty-seven subjects were enrolled: 37 received ethyl vinyl chloride vapocoolant spray, 48 received isopropyl alcohol spray (placebo), and 42 received no pretreatment. Mean VAS scores for pain experienced during cannulation were 34, 33, and 31 mL for each group, respectively. Ethyl vinyl chloride vapocoolant spray failed to measurably reduce pain associated with intravenous cannulation when compared to those pretreated with isopropyl alcohol spray or receiving no intervention.

Cancer pain management in children

Unrelieved pain may have a major impact on the care of children with cancer. The type and severity of pain experienced by children with cancer varies from acute, procedure-related pain to progressive chronic pain associated with the progression of the disease or sequelae of treatment. Drugs are the mainstay of treatment. Regular pain assessments combined with appropriate analgesic administration at regular dosing intervals, adjunctive drug therapy for control of adverse effects and associated symptoms, and nonpharmacological interventions are recommended. Although standard dosing of opioids adequately treats most cancer pain in children, more complex treatment is required by a significant group. Strategies to improve analgesia include the use of epidural or intrathecal infusions of a combination of opioids and other adjuvants, or other regional anaesthesia techniques. Procedure- and treatment-related pain is an even greater problem than cancer pain. Recommendations have been published with regard to the monitoring and personnel required when children are sedated which aim to set the standard of care and minimize both physical discomfort or pain and negative psychological responses, by providing analgesia; and to maximize the potential for amnesia; and to control behaviour.

Topical vapocoolant quickly and effectively reduces vaccine-associated pain: results of a randomized, single-blinded, placebo-controlled study

BACKGROUND

Comprehensive international travel preparation often requires several vaccines. Up to 90% of adults have some fear of injections, mostly due to injection-related pain. Pediatric studies with routine vaccines have shown topical anesthetic EMLA cream (lidocaine and prilocaine, Astra Pharmaceuticals, Inc.) and the topical vapocoolant Fluori-Methane (dichlorodifluoromethane and trichlorodifluoromethane, Gebauer Co.) to be equally effective in reducing pain from vaccinations. EMLA cream is expensive and requires a 60-min application, while Fluori-Methane (FM) is immediate in onset of action and inexpensive. Skin anesthesia begins at 10 degrees C. Fluori-Methane can briefly cool the skin to 0 degrees C.

METHODS

We studied the effectiveness of topical vapocoolant on adult clients at our international travel clinic in a randomized, controlled trial of topical FM vs. cold (4 degrees C) saline placebo. Using a preset randomization table, participants served as their own controls, receiving placebo/control or active agent (participant blinded) in one arm (left or right), and a similar number of vaccines in the untreated arm. Vaccines were administered according to a set protocol per arm to minimize the risk of bias. Pain was measured using a modified McGill present pain intensity (PPI) pain index. Subjects rated their pain immediately and at 5 min on a six-level scale, noting treated and untreated arms separately. A questionnaire was completed on intervention preferences. Sample size was predetermined to achieve 90% statistical power estimating 25% efficacy (minimum n=172).

RESULTS

One hundred and eighty-five participants were enrolled; 93 FM and 92 cold saline placebo. FM-treated arms had a significant reduction in immediate pain compared to untreated arms (pain scale mean 2.2 vs. 3.1; p<.0001), and compared to placebo (mean 2.2 vs. 2.8; p<.01). Delayed pain at 5 min was not affected by FM or control (mean 1.9 vs. 2.0) compared to no intervention (pain scale 1.9). The intervention preference questionnaire indicated that participants did not find FM therapy uncomfortable. They would choose FM therapy in the future, over a cream, especially if a wait was involved.

CONCLUSION

The topical vapocoolant Fluori-Methane is an effective, quick, preferred, inexpensive agent for reducing vaccine-associated injection pain for international travel clients.

Placebo interventions for all clinical conditions

BACKGROUND

Placebo interventions are often claimed to improve patient-reported and observer-reported outcomes, but this belief is not based on evidence from randomised trials that compare placebo with no treatment.

OBJECTIVES

To assess the effect of placebo interventions.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 4, 2002), MEDLINE (1966 to 2002), EMBASE (1980 to 2002), Biological Abstracts (1986 to 2002), and PsycLIT (1887 to 2002). We contacted experts on placebo research, and read references in the included trials.

SELECTION CRITERIA

We included randomised placebo trials with a no-treatment control group investigating any health problem.

DATA COLLECTION AND ANALYSIS

Two reviewers independently assessed trial quality and extracted data. We contacted study authors for additional information.

MAIN RESULTS

Outcome data were available in 156 out of 182 included trials, investigating 46 clinical conditions. We found no statistically significant pooled effect of placebo in 38 studies with binary outcomes (4284 patients), relative risk 0.95 (95% confidence interval (CI) 0.89 to 1.01). The pooled relative risk for patient-reported outcomes was 0.95 (95% CI 0.88 to 1.03) and for observer-reported outcomes 0.91 (95% CI 0.81 to 1.03). There was heterogeneity (P=0.01) but the funnel plot was symmetrical. There was no statistically significant effect of placebo interventions in the four clinical conditions investigated in three trials or more: pain, nausea, smoking, and depression, but confidence intervals were wide. We found an overall effect of placebo treatments in 118 trials with continuous outcomes (7453 patients), standardised mean difference (SMD) -0.24 (95% CI -0.31 to -0.17). The SMD for patient-reported outcomes was -0.30 (95% CI -0.38 to -0.21), whereas no statistically significant effect was found for observer-reported outcomes, SMD -0.10 (95% CI -0.20 to -0.01). There was heterogeneity (P<0.001) and large variability in funnel plot results even for big trials. There was an apparent effect of placebo interventions on pain (SMD -0.25 (95% CI -0.35 to-0.16)), and phobia (SMD -0.63 (95% CI -1.17 to -0.08)); but also a substantial risk of bias. There was no statistically significant effect of placebo interventions in eight other clinical conditions investigated in three trials or more: nausea, smoking, depression, overweight, asthma, hypertension, insomnia and anxiety, but confidence intervals were wide.

REVIEWERS' CONCLUSIONS

There was no evidence that placebo interventions in general have clinically important effects. A possible small effect on continuous patient-reported outcomes, especially pain, could not be clearly distinguished from bias.

The use of botulinum toxin in pediatric disorders

Botulinum toxins have an exciting and important role in treating the child with hypertonia. The guidelines presented in this article are those that have been published representing the safe use of botulinum toxins in children. Experience and a decade of research have provided the framework for using botulinum toxins in decreasing deformity and promoting function. In children, a window of opportunity exists with botulinum toxin that allows improved motor control and elongation of shortened muscles. Although 3 to 4 months in an adult life is short, for a child it is a relatively greater proportion of their life experience and may be long enough for skill development. The improvement noted in function after botulinum toxin use is facilitated by comprehensive rehabilitation. The pediatric physiatrist has a unique role in the management of children with cerebral palsy and other conditions with hypertonia. Their knowledge and training reflect an understanding of anatomy and development that allows accurate evaluation of specific functional problems in children related to hypertonia. The pediatric physiatrist has experience in localization of muscles by EMG, nerve stimulation, and surface anatomy. Although many other physicians inject botulinum toxins, goal-directed management is the cornerstone to the physiatrist's thinking and treatment plan. Orthopedic surgery ultimately may be the intervention of choice if persistent contracture or progression of contractures occurs. Working in collaboration with an orthopedist identifies the timing of optimal surgical intervention for alignment. For persistent and severe hypertonia, the treatment team includes a neurosurgeon. All options for spasticity, such as selective posterior rhizotomy and intrathecal baclofen, should be considered. Re-evaluation of the child after selective dorsal rhizotomy or intrathecal baclofen is appropriate and should be discussed with therapists for focal intervention. Communication between members of the team and the family is desirable and frequently is one of the major contributions of the pediatric physiatrist. For children with focal hypertonia, botulinum toxins offer a dramatic but temporary repeatable change that affects rehabilitation. Research rapidly has captured the positive effect of the toxins on impairment and functional limitations. Not to be overlooked are outcomes related to quality of life. The long-term use of botulinum toxins and the role the toxins play throughout the life span of the person with a childhood hypertonic disorder are yet to be determined.

Placebo treatment versus no treatment

BACKGROUND

Placebo interventions are often believed to improve patient reported and observer reported outcomes, but this belief is not based on evidence from randomised trials that compare placebo with no treatment.

OBJECTIVES

To assess the effect of placebo interventions.

SEARCH STRATEGY

We searched the Cochrane Controlled Trials Register (The Cochrane Library, issue 3, 1998), MEDLINE (Jan 1966 to Dec 1998), EMBASE (Jan 1980 to Dec 1998), Biological Abstracts (Jan 1986 to Dec 1998), PsycLIT (Jan 1887 to Dec 1998). Experts on placebo research were contacted and references in the included trials were read.

SELECTION CRITERIA

Randomised placebo trials with a no-treatment control group investigating any health problem were included.

DATA COLLECTION AND ANALYSIS

Two reviewers independently assessed trial quality and extracted data. Study authors were contacted for additional information.

MAIN RESULTS

Outcome data were available in 114 out of 130 included trials, investigating 40 clinical conditions. Outcomes were binary in 32 trials (3795 patients) and continuous in 82 (4730 patients). We found no statistically significant pooled effect of placebo in studies with binary outcomes, relative risk 0.95 (95 per cent confidence interval 0.88 to 1.02). The pooled relative risk for subjective (patient reported) outcomes was 0.95 (0.86 to 1.05) and for objective (observer reported) outcomes 0.91 (0.80 to 1.04). There was statistically significant heterogeneity (P < 0.03), but no evidence of sample size bias (P = 0.56). We found an overall positive effect of placebo treatments in trials with continuous outcomes, standardised mean difference -0.28 (95 per cent confidence interval -0.38 to -0.19). The standardised mean difference for subjective outcomes was -0.36 (-0.47 to -0.25), whereas no statistically significant effect was found for objective outcomes, standardised mean difference -0.12 (-0.27 to 0.03). There was statistically significant heterogeneity (P < 0.001), and evidence of sample size bias (P = 0.05). There was no statistically significant effect of placebo interventions in eight out of nine clinical conditions investigated in three trials or more (nausea, relapse in prevention of smoking and depression, overweight, asthma, hypertension, insomnia and anxiety), but confidence intervals were wide. There was a modest apparent analgesic effect of placebo interventions, standardised mean difference -0.27 (-0.40 to -0.15), but also a substantial risk of bias.

REVIEWER'S CONCLUSIONS

There was no evidence that placebo interventions in general have clinically important effects. A possible moderate effect on subjective continuous outcomes, especially pain, could not be clearly distinguished from bias.

Making vaccines more acceptable--methods to prevent and minimize pain and other common adverse events associated with vaccines

The growing abundance of highly immunogenic vaccines has arrived with a burden of pain, distress, and common adverse reactions that in turn may interfere with parental compliance and aggravate anti-vaccine sentiment. In a study of 150 children in each of 2 age-groups, we found that approximately 20% of the subjects suffered serious distress or worse. During the procedural phase, approximately 90% of the 15-to-18 month old children and 45% of the 4-to-6 year old children showed serious distress or worse. To address non-adherence with pediatric vaccine schedules, we must consider all of the possible issues that might prevent a parent from taking a child to a health care provider for vaccination. In that same study we identified useful predictors for both preparatory and procedural distress - predictors that might be used in identifying children who might benefit from preventive interventions. Vaccine providers might consider a variety of interventions. Attitude, empathy, instruction, and practice have all been shown to have a salutatory effect upon pain and anxiety with medical procedures in general and specifically with vaccinations. Distraction has also been found to be an effective method for distress and pain prevention in children. More formal methods of clinical hypnosis which combine a deep state of relaxation with focused imagery and suggestion have also been found to be effective in helping children and adolescents prepare for, cope with, and tolerate the pain and anxiety associated with medical procedures. So-called 'sugar nipples' delivering small amounts of sucrose orally at the time of a painful procedure in an infant has been not been shown to decrease vaccination pain and studies on refrigerant topical anesthetics are mixed. Studies have found a eutectic mixture of 2.5% lidocaine and 2.5% prilocaine (EMLA) effective in providing adequate local anesthesia in children, but it suffers from problems in practical application. Studies with various injection techniques have not identified ready solutions, and although jet injection appears to provoke less anxiety and cause less immediate pain, studies also indicate a somewhat greater incidence of delayed local reactogenicity including soreness and edema. Other measures to prevent or rapidly treat other common adverse events have been shown effective and should be considered as well.

Taking the "ouch" out of injections for children. Using distraction to decrease pain

PURPOSE

This research compared the effect of two forms of distraction on injection pain in a convenience sample of preschool children.

DESIGN

A quasi-experimental study of 105 children (53 girls and 52 boys) ages 4 to 6 years needing DPT immunizations. Data were collected at three sites: two school-based immunization clinics and one public health center with a walk-in immunization program.

METHODS

Study children were randomly assigned to receive one of three treatments with their DTP injection: touch, bubble-blowing, or standard care. Prior to injection, a measure of medical fear was obtained (Child Medical Fear Scale) and pain was measured through use of the Oucher Scale.

DATA ANALYSIS

Planned comparisons within analysis of variance (ANOVA) tested the differences in pain scores by treatment. Factorial ANOVA was used to determine the influence of age or gender on treatment, and the effect of medical fear on pain was analyzed using correlational statistics and factorial ANOVA.

RESULTS

Both forms of distraction, touch and bubble-blowing, significantly reduced pain perception. There were no interaction effects of either age or gender. Fear was a significant covariate, but distraction was effective even when fear was not held constant.

CLINICAL IMPLICATIONS

Distraction appears to be an effective method for decreasing injection pain in young children. It is an easy, practical nursing intervention to help children cope with this common, painful experience.

Topical anesthetics in dermatology

Topical anesthetics are valuable tools for the dermatologists. The purpose of this study is to educate dermatologists about the pharmacology and clinical applications of topical anesthetics. A review of the current topical anesthetics was conducted. Several topical anesthetics are available to provide safe and effective cutaneous analgesia. Patient care can be improved by reducing the discomfort of local procedures and by minimizing the side effects of the anesthetics.

Reducing children's immunization distress in a primary care setting

The purpose of this study was to compare two brief, inexpensive distraction techniques for children receiving immunizations during a county-sponsored immunization clinic. Preschool children (n = 80) were assigned to a party blower intervention, a pinwheel intervention, or a control group. Nurses were instructed to use "standard instructions" for the control group, and to simply provide the distracter and encourage use, but not to spend time trying to train the child or force them to use it, for the other groups. Results of planned comparisons indicated significant party blower results in the children's ratings of reduced distress (P < .01) and the parents' ratings of having to hold their child less strongly (P = .04), and showed it to be more distracting than the pinwheel (P < .02). The overall pattern of results on all rating scales supports the efficacy of using a party blower for reducing children's immunization distress, with minimal staff training and no procedural delay.

The effectiveness of ice as a topical anesthetic for the insertion of intravenous catheters

In a paired clinical trial, the effectiveness of ice in reducing the pain of intravenous catheter placement was assessed in 28 adult volunteers. An ice pack was placed over one arm for 10 minutes, followed by insertion of an 18-gauge angiocatheter in both arms. Patients recorded their pain assessment after each venipuncture on a previously validated 100-mm visual analog scale (VAS) and identified their preferred method for the procedure (pretreatment with ice or no pretreatment). The mean pain score for catheter placement on arms pretreated with ice was 27.5+/-15.9 mm; the mean pain score for the control arms was 34.2+/-21.6 mm (P = .17). Most patients (61%) preferred no pretreatment (P = .014). Although most men (75%) preferred no pretreatment, 75% of women preferred pretreatment with ice (P = .014). Future studies should examine whether ice is effective at reducing pain from other more painful procedures and whether the response to ice is gender-related.