Mary-Ellen Hogan

Systematic Review and Meta-analysis of the Effect of Warming Local Anesthetics on Injection Pain

STUDY OBJECTIVE Local anesthetics are the main class of analgesics used for pain management during laceration repair and other minor surgeries; however, they are administered by injection, which is painful. Warming local anesthetics has been proposed as a cost-free intervention that reduces injection pain. A systematic review of the effectiveness of this technique has not yet been undertaken. We determine the effectiveness of warming local anesthetics to reduce pain in adults and children undergoing local anesthetic infiltration into intradermal or subcutaneous tissue. METHODS We used published articles from MEDLINE (1950 to June 2010), EMBASE (1980 to June 2010), CINAHL (1982 to June 2010), the Cochrane Library (second quarter 2010), International Pharmaceutical Abstracts (1970 to June 2010), and ProQuest Dissertations and Theses database (1938 to June 2010). We included studies with randomized or pseudorandomized designs and healthy subjects or patients receiving subcutaneous or intradermal injection of local anesthetics that were warmed (body temperature) or not (room temperature). Studies of regional anesthesia and intraarticular, spinal, or periorbital administration of local anesthetics were excluded. Data were extracted onto predesigned forms and verified by 2 reviewers. Quality was assessed with the Cochrane risk of bias tool. The primary outcome was self-reported pain as assessed by a visual analog or numeric rating scale. Data were combined with mean differences with 95% confidence intervals (CIs) by using a random-effects model. RESULTS Twenty-nine studies were retrieved for close examination and 19 studies met inclusion criteria. A total of 18 studies with 831 patients could be included in a meta-analysis. Seventeen studies had an unclear risk of bias and 1 had a high risk of bias. A mean difference of -11 mm (95% CI -14 to -7 mm) on a 100-mm scale was found in favor of warming local anesthetics. Subgroup analysis of 8 studies investigating the effect of warming on buffered local anesthetics yielded similar results: -7 mm (95% CI -12 to -3 mm). CONCLUSION Warming local anesthetics leads to less pain during injection and therefore should be done before administration.

Improvements in Pain Outcomes in a Canadian Pediatric Teaching Hospital Following Implementation of a Multifaceted, Knowledge Translation Initiative

BACKGROUND A previous audit performed at a tertiary ⁄ quaternary pediatric hospital in Toronto, Ontario, demonstrated suboptimal assessment and treatment of childrens pain. Knowledge translation (KT) initiatives (education, reminders, audit and feedback) were implemented to address identified care gaps; however, the impact is unknown. OBJECTIVES To determine the impact of KT initiatives on pain outcomes including process outcomes (eg, pain assessment and management practices) and clinical outcomes (eg, pain prevalence and intensity); and to benchmark additional pain practices, particularly opioid administration and painful procedures. METHODS Medical records at The Hospital for Sick Children (Toronto, Ontario) were reviewed on a single day in September 2007. Pain assessment and management practices, and pain prevalence and intensity in the preceding 24 h were recorded on a standardized data collection form. Where possible, pain outcomes were compared with previous audit results. RESULTS Records of 265 inpatients were audited. Sixty-three per cent of children underwent a documented pain assessment compared with 27% in an audit conducted previously (P<0.01). Eighty-three per cent of children with documented pain received at least one pain management intervention. Overall, 51% of children received pharmacological therapy, and 15% received either a psychological or physical pain-relieving intervention. Of those assessed, 44% experienced pain in the previous 24 h versus 66% in the previous audit (P<0.01). Fewer children experienced severe pain compared with the first audit (8.7% versus 26.1%; P<0.01). One-third of children received opioids; 19% of these had no recorded pain assessment. Among 131 children who underwent a painful procedure, 21% had a concurrent pain assessment. Painful procedures were accompanied by a pain-relieving intervention in 12.5% of cases. CONCLUSIONS Following KT initiatives, significant improvements in pain processes (pain assessment documentation and pain management interventions) and clinical outcomes (pain prevalence, pain intensity) were observed. Further improvements are recommended, specifically with respect to procedural pain practices and opioid utilization patterns.

A systematic review of vapocoolants for reducing pain from venipuncture and venous cannulation in children and adults.

BACKGROUND Studies of vapocoolants for pain reduction from venipuncture have demonstrated conflicting results. OBJECTIVE Our aim was to systematically review the literature regarding the analgesic effectiveness of vapocoolants in children and adults. METHODS We searched MEDLINE, EMBASE, CINAHL (Cumulative Index to Nursing and Allied Health Literature), and Cochrane Central Register of Trials using key words: vapocoolant, pain, venipuncture, and cannulation. We included randomized or quasi-randomized studies comparing vapocoolants to placebo or no treatment. Two authors reviewed titles and abstracts and extracted data. Quality was assessed by consensus using the Cochrane risk of bias tool. The primary outcome was self-reported pain using a 100-mm visual analog scale, a 0- to 10-point numerical scale, or observational scale for preverbal children. Data were pooled using a random effects model. RESULTS Twelve studies including 1266 patients (509 children, 757 adults) were identified. No significant pain reduction was found in children receiving vapocoolants vs. placebo or no treatment (mean difference -10 mm; 95% confidence interval [CI] -26 to 6). In adults, less pain was reported when vapocoolants were compared with no treatment: -10 mm on a 100-mm scale (95% CI -17 to -4); but not when compared to placebo (-12 mm; 95% CI -26 to 2). Pain from application of vapocoolants was greater than placebo (8 mm; 95% CI 4 to 2). CONCLUSIONS Vapocoolants were ineffective in children and adults when compared to placebo, and effective in adults only when compared to no treatment. The magnitude of effect was low and was offset by increased pain from application. They cannot be recommended for routine use in children or adults.

Evaluation of the reliability, validity and practicality of 3 measures of acute pain in infants undergoing immunization injections.

There is a need to identify a primary measure of infant pain that can be used to assess pain in infants undergoing vaccine injections in order to facilitate vaccine outcomes research. The aim of the present study was to determine the reliability, validity and practicality of 3 measures of acute pain in infants; the Modified Behavioural Pain Scale (MBPS), Neonatal Infant Pain Scale (NIPS), and Face Legs Activity Cry Consolability Scale (FLACC). Five raters rated pain from videotapes in 120 infants aged 2-6 months undergoing vaccine injections that participated in a randomized controlled trial designed to compare pain responses between two vaccines, DPTaP-Hib vaccine and PCV vaccine. Inter-rater reliability coefficients for baseline and vaccine injections were all greater than 0.85. Cronbachs alpha ranged from 0.83 to 0.94. Construct validity was demonstrated for all measures by vaccine injection scores that were higher (p<0.001) than baseline scores and by PCV scores that were higher than DPTaP-Hib scores. Concurrent validity was demonstrated by bi-variate correlation coefficients that ranged from 0.84 to 0.92. Intra-rater reliability coefficients for scores obtained after a single viewing (simulating real time assessment) versus multiple viewings were ≥ 0.96. All measures demonstrated a significant difference in pain scores between the more painful (PCV) and less painful (DPTaP-Hib) vaccine for scores obtained after a single viewing. The majority of raters (4 out of 5) preferred the MBPS. Together, these results provide preliminary support for the MBPS as the primary outcome of pain during vaccine injections in infants.

A systematic review of measures for reducing injection pain during adult immunization

OBJECTIVE To evaluate the effectiveness of different pain-relieving interventions to reduce pain from immunization in adults. DATA SOURCES MEDLINE (1950 to October Week 3 2008) PsycINFO (1967 to December Week 1 2008), CINAHL (1982 to October Week 4 2008), EMBASE (1980 to 2008 Week 43) and the Cochrane Central Register of Controlled Trials (3rd Quarter 2008). REVIEW METHODS Databases were searched for trials of pharmacological, behavioural, physical or operator-dependant techniques to reduce pain from immunization in adults. The primary outcome was pain as assessed by visual analogue scale or other numeric rating scale. RESULTS Six studies representing 853 participants were identified. One study evaluating pharmacological interventions (lidocaine-prilocaine) found them to be effective in reducing pain from immunization. Similarly, two studies evaluating physical pain relieving techniques, either skin cooling interventions (Fluori-Methane) or tactile stimulation (manual pressure at the site of injection) found them to reduce pain. One study of jet injectors found them to be more painful than conventional needle and syringe. Neither freezing needles nor warming vaccines was found to be effective in reducing pain. No studies investigated psychological interventions or oral analgesics (acetaminophen and ibuprofen). CONCLUSION There was limited evidence to support the use of lidocaine-prilocaine, Fluori-Methane and manual pressure for reducing immunization pain in adults. There was limited evidence of more pain with jet injectors compared to needle and syringe. Due to limited data, we recommend further investigation of methods to reduce immunization pain in adults, primarily psychological and physical techniques.

A randomized controlled trial of analgesia during vaccination in adults

Although immunization injections are the most common painful medical procedures, pain-relieving interventions are not routinely used. In this randomized controlled trial, we compared the effectiveness of topical anesthesia using liposomal lidocaine to: (1) vapocoolant spray using a proprietary blend of 1,1,1,3,3-pentafluoropropane and 1,1,1,2-tetrafluoroethane; (2) nurse-administered tactile stimulation; or (3) self-directed distraction by means of reading a magazine. Liposomal lidocaine was more effective (p<or=0.05) than distraction, as assessed by self-reported pain using the visual analog scale and global report, but did not differ from either vapocoolant spray or tactile stimulation. This information can be incorporated in immunization programs.

Addressing parental concerns about pain during childhood vaccination: is there enough time to include pain management in the ambulatory setting?

Objective:Pain from vaccine injections remains undertreated, despite the availability of numerous pain-relieving strategies. Healthcare providers report lack of time within current office workflows as a major barrier to routine pain management. The objective was to document the total time involved in outpatient vaccine appointments to test the hypothesis that offering pain-relieving strategies can be practically implemented when considering the element of time to vaccine injection. Patients and Methods:Prospective naturalistic study in 8 urban outpatient primary care clinics (4 pediatric and 4 family practice) in Toronto. For 48 to 59 consecutive childhood vaccination appointments at each site, child waiting time from clinic arrival until first vaccine injection was tracked. Results:Altogether, 405 vaccine appointments were included. The median age of the child undergoing vaccination was 12 months. The mean (SD) time from clinic arrival until first vaccine injection was 41.6 minutes (20.9), with a range of 7 to 132 minutes. Linear regression identified a significant (P<0.05) difference according to clinic [ranging from 19.4 min (6.5) to 57.5 min (20.2)] and number of family members in the appointment [ranging from 40.6 min (21.0) for an appointment in the index child only to 50 min (14.3) for an appointment in the index child and 2 other family members]. Conclusions:Contrary to healthcare provider perceptions, the timing of outpatient childhood vaccine appointments allows for the inclusion of pain management interventions. Efforts should now focus on educating healthcare providers and parents about the value of pain management and how to implement evidence-based strategies.

Effect of Liposomal Lidocaine and Sucrose Alone and in Combination for Venipuncture Pain in Newborns

OBJECTIVE: To determine the relative effectiveness of liposomal lidocaine, sucrose, and their combination for reducing pain in term newborns. METHODS: Ours was a double-blind, randomized, controlled, double-dummy trial of 330 healthy term newborns. Before venipuncture for the newborn screening test, neonates received (1) 1 g of liposomal lidocaine cream topically, (2) 2 mL of 24% sucrose solution orally, or (3) sucrose and liposomal lidocaine. The facial grimacing score (0–100) was used to assess pain. Adverse events and lidocaine levels were used to assess safety. RESULTS: Infant characteristics did not differ among groups. Facial grimacing scores were lower in the sucrose group compared with those in the liposomal lidocaine group (mean difference: −27 [95% confidence interval (CI): −36 to −19; P < .001) and for the sucrose plus liposomal lidocaine group compared with those in the liposomal lidocaine group (mean difference: −23 [95% CI: −31 to −14]; P < .001). The sucrose and sucrose plus liposomal lidocaine groups did not differ (mean difference: −5 [95% CI: −13 to 4]; P = .3). Local skin reactions were not observed, and the incidence of spitting up did not differ between sucrose-exposed and non–sucrose-exposed infants (1.4% vs 2.7%, respectively; P = .22). The mean (SD) plasma lidocaine level was 44.6 (55.3) ng/mL. CONCLUSIONS: Sucrose was more effective than liposomal lidocaine for reducing pain during venipuncture in newborns. The addition of liposomal lidocaine to sucrose did not confer any additional benefit to sucrose alone. There was no evidence of harm from liposomal lidocaine or sucrose.

A randomized-controlled trial of parent-led tactile stimulation to reduce pain during infant immunization injections.

Objective:To determine the effectiveness of parent-led tactile stimulation for pain reduction when added to a combination of evidence-based pain-reducing interventions in infants undergoing immunization injections. Methods:Healthy infants aged 4 to 6 months undergoing routine immunization at a primary care practice were eligible. Infants were randomized to tactile stimulation by a parent or usual care. Parents in the tactile stimulation group rubbed the ipsilateral thigh distal to the site for 15 seconds before, during, and after injections. In addition, all infants received evidence-based pain-relieving interventions including: sucrose solution, holding by a parent, and intramuscular injection without aspiration. The primary outcome was pain, measured by a validated tool, the Modified Behavioral Pain Scale (MBPS), by an observer unaware of treatment allocation using videotapes of the procedure. MBPS scores could range from 0 (no pain) to 10 (maximum pain). Parents, unaware of the study hypothesis, also rated infant pain in real time using a 100 mm visual analogue scale. Results:One hundred twenty infants participated. Infant characteristics did not differ (P>0.05) between the tactile stimulation and control groups. Mean MBPS scores and parent visual analogue scale scores did not differ between groups (8.2 [1.1] vs. 8.0 [1.3]; P=0.57) and (60 [20] vs. 53 [22] mm; P=0.10), respectively. Discussion:Parent-led tactile stimulation did not reduce pain in infants undergoing immunization injections when combined with other pain-relieving interventions. Potential reasons for the lack of effectiveness are discussed. Investigation of the effectiveness of clinician-led tactile stimulation in this population is recommended.

Incremental health care costs for chronic pain in Ontario, Canada: a population-based matched cohort study of adolescents and adults using administrative data.

Abstract Little is known about the economic burden of chronic pain and how chronic pain affects health care utilization. We aimed to estimate the annual per-person incremental medical cost and health care utilization for chronic pain in the Ontario population from the perspective of the public payer. We performed a retrospective cohort study using Ontario health care databases and the electronically linked Canadian Community Health Survey (CCHS) from 2000 to 2011. We identified subjects aged ≥12 years from the CCHS with chronic pain and closely matched them to individuals without pain using propensity score matching methods. We used linked data to determine mean 1-year per-person health care costs and utilization for each group and mean incremental cost for chronic pain. All costs are reported in 2014 Canadian dollars. After matching, we had 19,138 pairs of CCHS respondents with and without chronic pain. The average age was 55 years (SD = 18) and 61% were female. The incremental cost to manage chronic pain was