- Email: [email protected]
Clinically meaningful reduction in pain severity in children treated by paramedics: a retrospective cohort study
American Journal of Emergency Medicine 33 (2015) 1587–1590
Contents lists available at ScienceDirect
American Journal of Emergency Medicine journal homepage: www.elsevier.com/locate/ajem
Original Contribution
Clinically meaningful reduction in pain severity in children treated by paramedics: a retrospective cohort study Paul A. Jennings, PhD a,b,c,⁎, Bill Lord, PhD d, Karen Smith, PhD b,e,f a
Department of Community Emergency Health and Paramedic Practice, Monash University, Caulfield East, Victoria, Australia Ambulance Victoria, Doncaster, Victoria, Australia Emergency & Trauma Centre, The Alfred Hospital, Melbourne, Victoria, Australia d School of Nursing, Midwifery and Paramedicine, University of the Sunshine Coast, Sippy Downs, Queensland, Australia e Department of Epidemiology and Preventive Medicine, Monash University, Melbourne, Victoria, Australia f Discipline–Emergency Medicine, University of Western Australia, Crawley, Western Australia, Australia b c
a r t i c l e
i n f o
Article history: Received 21 April 2015 Received in revised form 15 June 2015 Accepted 16 June 2015
a b s t r a c t Introduction: Pediatric pain is a common presenting symptom in the prehospital setting; however, there is a lack of data identifying factors associated with effective pain management in this population. We sought to identify the factors associated with clinically meaningful pain reduction in children. Methods: An analysis of electronic patient care records of all patients younger than 15 years presenting with pain to the emergency medical service of Victoria, Australia, over a 4-year period (2008-2011). Data were analyzed using descriptive statistics and multivariate regression to assess predictors of clinically meaningful pain reduction. Clinically meaningful pain reduction was defined as a reduction of 2 or more points on an 11-point scale. Results: A total of 92378 children were transported, of whom 15016 (16.3%) met the inclusion criteria. The median age was 11 (interquartile range, 9-13) years, and 59.2% were male. Patients older than 9 years were less likely (adjusted odds ratio [AOR], 0.5; 95% confidence interval [CI], 0.4-0.6) and boys were more likely (adjusted odds ratio, 1.1; 95% CI, 1.0-1.3) to have a clinically meaningful reduction in pain. Patients with pain classified as musculoskeletal were more likely to achieve a reduction in pain score of 2 or more when compared with pain due to other medical causes (AOR, 1.7; 95% CI, 1.5-1.9). Conclusions: Factors other than the type of analgesia are important determinants of prehospital pain relief and are likely to impact on clinical care and research. Clinical audit and research projects should stratify patients according to patient as well as management factors to maximize service improvement. © 2015 Elsevier Inc. All rights reserved.
1. Introduction Exposure to children with pain is very common in the prehospital and emergency setting. Despite being a frequent presentation, there is limited evidence regarding factors associated with the likelihood of a clinically meaningful reduction in pain severity in the paramedic practice setting. Early, effective pain management in both the emergency medical service (EMS) and emergency department settings is an important component of care and may play a role in reducing the likelihood of chronic pain syndromes and pain-related anxiety and posttraumatic stress after the acute phase [1–6]. Paramedics generally have a range of pharmacologic and nonpharmacologic pain management strategies available. An ability to identify demographic, injury, and management factors that are associated with the likelihood of successfully achieving clinically important pain reduction is important to clinicians. Knowledge of factors which improve or inhibit the likelihood of clinically important pain reduction ⁎ Corresponding author at: Monash University, Building C (503), Level 4, 900 Dandenong Rd, Caulfield East, VIC 3145, Australia. Tel.: +61 3 9904 4264. E-mail address: [email protected] (P.A. Jennings). http://dx.doi.org/10.1016/j.ajem.2015.06.026 0735-6757/© 2015 Elsevier Inc. All rights reserved.
in children allows the clinician to focus their attention on strategies to optimize their pain management plan. Barriers to adequate analgesia administration have been previously reported in the provision of analgesia to both adults and children [7,8]. Qualitative studies have suggested that paramedics decision making around the provision and type of analgesia to be administered can be influenced by the patients' age [8], concern of adverse effects, organizational norms and beliefs about opioids, and provider knowledge of pediatric parenteral analgesia options [7]. This study aims to identify the factors associated with the clinically meaningful reduction in pain severity in children who were treated by paramedics in a busy EMS.
2. Methods 2.1. Study design This retrospective cohort study analyzed pediatric patients 14 years or younger who were treated and transported by paramedics in Victoria, Australia, between January 1, 2008, and December 31, 2011.
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P.A. Jennings et al. / American Journal of Emergency Medicine 33 (2015) 1587–1590
Ethics Committee approval was received by the Monash University Human Research Ethics Committee (A/12/383), and access to deidentified patient data was approved by Ambulance Victoria.
measure was the proportion of patients with a clinically meaningful reduction in pain severity defined as a pain rating reduction of 2 or more points on an 11-point VNRS.
2.2. Study population and setting
3. Results
Ambulance Victoria is the sole statewide provider of emergency ambulance services for a population of approximately 5.5 million people in a region that covers more than 227 000 km2, with more than 4.3 million residing in metropolitan Melbourne [9]. Paramedics responded to approximately 800 000 incidents in 2001 [10], resulting in 360 766 patients being transported. Pediatric patients represented 7.1% (n = 25 563) of this caseload. The scope of practice for paramedics used in this jurisdiction includes inhaled methoxyflurane, parenteral morphine sulphate or fentanyl according to clinical practice guidelines. There are no age restrictions placed on the administration of opioids, the drugs are indicated for pain of any cause, and medical consultation is not required. Fentanyl via the intranasal route was added to the pain management guideline for children in 2009. All patient-level data are collected via an in-field electronic patient care record (ePCR) system (VACIS, VACIS Collaboration, Melbourne). Paramedics enter scene findings, patient demographic data, clinical observations, and treatment data directly into the ePCR both during and after the episode of care. Clinical, administrative, and operational data are then maintained in a data warehouse [11]. Paramedics use several pain severity rating scales in this setting, most commonly the verbal numeric rating scale (VNRS), which is an 11-point scale whereby the patient is required to rate their pain severity between 0 and 10, with 0 meaning no pain and 10 the worst pain imaginable [12]. In young children, the Wong-Baker Faces pain scale is used to assess pain severity, and the Face, Legs, Activity, Cry, Consolability scale is recommended for pain assessment in infants and preverbal children [13,14]. Where that patient has difficulty in reporting a numerical rating, paramedics may record an adjective to rate the pain [15]. The adjective is subsequently converted to a numeric pain severity rating, where “none” represents 0; “mild, ”2; “moderate, ” 5; and “severe,” 8. Clinically meaningful pain reduction was defined as a final pain severity score recorded on VACIS as 2 or more less than the initial pain severity score. A reduction of 2 or more was selected, as a visual analog pain score reduction of 10 mm in children has been previously shown to be the minimum clinically significant difference whereby a patient is likely to report feeling “a bit better” or “a bit worse” [16]. Another study reported a reduction of 2 points was required for a child to recognized a difference in pain severity [17]. Cases were included if the patient was transported between January 1, 2008, December 31, 2011; the patient was younger than 15 years; “pain” was recorded in secondary survey, assessment, or patient complaint field; or a pain score higher than 0 was reported at any time during care. Cases were excluded if the initial or final pain score was missing, or the initial pain score was less than 3.
During the study period, January 1, 2008, December 31, 2011, 92 378 children aged less than 15 years had an ambulance dispatched and AV paramedics attend, 38 167 (41.3%) of which reported pain at any time after ambulance arrival. Of the children presenting with pain, 23 151 (60.6%) were excluded based on study criteria (Figure). This left 15 016 children for inclusion in the analysis. The demographics of those who achieved and did not achieve clinically meaningful pain severity reduction are provided in Table 1. Of the 15 016 children who were attended by paramedics with an initial pain score greater than 3 and available initial and final pain scores, 12 346 (82.2%) of 15 016 achieved clinically important pain reduction. Most of the children presenting with a VNRS of 3 or greater were male (60.7%) and aged between 10 and 14 years (70.2%). The median time to first analgesia was 11 minutes (interquartile range [IQR], 9-13 minutes), and there was little difference between those who achieved clinically important pain reduction and those who did not. The etiology of the children's pain was assigned a category based on the paramedic's assessment of case nature and is presented in Table 1, categorized by pain severity improvement. Musculoskeletal injury was the most common case nature encountered in this cohort (74.2%). The group of children who achieved clinically important pain severity reduction presented with a higher median (IQR) initial pain score than the group who did not (7 [5-8] vs 5 [4-7]; P b .001; Table 1). Most of the children with pain (78.8%) received an analgesic agent (either methoxyflurane or morphine sulphate or fentanyl). A small number (3.8%; 575/15 016) of children (or their parents/guardians) were reported to have refused the offer of analgesia, and paramedics reported withholding analgesia when indicated in 1.0% (147/15 016) of cases, which is most often due to contraindications. Inhaled methoxyflurane was the most common agent administered to children reporting pain (69.8%; 10 483/15016), followed by intranasal or intravenous fentanyl (16.5%; 2480/15 016) and intravenous morphine (6.6%; 996/ 15 016). More male than female children received an analgesic agent (79.8% vs 77.1%; P b .001). The odds of achieving clinically significant pain reduction was more than 6 times greater in children who received analgesia when compared with those who did not (adjusted odds ratio [AOR], 6.6; 95% CI, 5.9-7.3). Of all the analgesic agents, methoxyflurane was associated with the greatest odds of achieving clinically important pain reduction (AOR, 5.3; 95% CI, 4.8-5.9; Table 2).
Considered for inclusion N = 92,378
2.3. Statistical analysis Descriptive statistics and logistic regression were used to test the association between clinically meaningful pain reduction and the independent variables. The χ 2 test was used to test associations between categorical variables and the Wilcoxon rank sum test for associates between continuous variables that were not normally distributed. The independent variables used in the multivariate regression analysis were age, sex, pain cause, initial pain score, administration of any analgesia, and case year and were selected as univariate analysis indicated that they were statistically associated with the dependent variable at the .05 significance level. Odds ratios and their associated 95% confidence intervals (CIs) were calculated. All statistical analyses were considered to be significant at the .05 level. Stata Statistical Version 12 (StataCorp, College Station, TX) was used for data analysis. The primary outcome
• Did not meet inclusion criteria =54,211 • Initial Pain Score < 3 = 14,372 • Initial OR final Pain Score not available = 8,779 Total N = 77,362
Final cases included in analysis N = 15,016
Figure. Flowchart for included patients.
P.A. Jennings et al. / American Journal of Emergency Medicine 33 (2015) 1587–1590 Table 1 Characteristics of children by pain improvement Characteristic
Age (y), median (IQR) Age, n (%) 0-4 y 5-9 y 10-14 y Sex, n (%) Female Male Case nature (musculoskeletal), n (%) Other (including medical cause) Unknown Trauma other Burns Poisoning Cardiac Time to first analgesia (min), median (IQR)b Pain score, median (IQR) Initial pain Final pain Pain difference
No clinically meaningful improvement (n = 2670) 12 (10-13)
Clinically Total meaningful (n = 15 016) improvement (n = 12 346)
Pa
11 (9-13) b.001
11 (9-13)
114 (4.3) 540 (20.2) 408 (75.5)
644 (5.2) 3182 (25.7) 8520 (69.0)
758 (5.0) 3722 (24.8) 10 536 (70.2)
b.001
2016 (42.8) 1526 (57.2) 1572 (58.9)
4764 (38.6) 7582 (61.4) 9578 (77.6)
5908 (39.3) 9108 (60.7) 11 150 (74.2)
b.001
820 (30.7)
1711 (13.9)
2531 (16.9)
101 (3.8) 87 (3.3) 36 (1.4) 33 (1.2) 21 (0.8) 6 (3-12)
342 (2.8) 338 (2.7) 306 (2.5) 23 (0.2) 48 (0.4) 4 (2-7)
443 (3.0) 425 (2.8) 342 (2.3) 56 (0.4) 69 (0.4) 4 (3-7)
5 (4-7) 5 (4-7) 0 (0-1)
7 (5-8) 2 (1-3) 5 (3-6)
7 (5-8) 2 (1-4) 4 (2-6)
b.001
b.001
b.001 b.001 b.001
a
Association between no clinically important pain reduction and clinically important pain reduction. b Time interval between patient access by the paramedic and time of first analgesic administration.
The odds of achieving clinically important pain reduction were also associated with other patient characteristics. Children aged 5 to 9 years (AOR, 0.7; 95% CI, 0.6-0.95) and aged 10 to 14 years (AOR, 0.5; 95% CI, 0.4-0.6) had less odds of achieving clinically important pain reduction than their young (b3 years) counterparts. Boys had slightly greater odds than girls of experiencing clinically important pain reduction (AOR, 1.1; 95% CI, 1.1-1.3). Case nature was also associated with the odds of achieving clinically important pain reduction. The initial pain severity reported by children was a strong independent predictor of the odds of achieving clinically important pain reduction. Those with more severe pain were more likely to have their pain relived (Table 3). Furthermore, more severe pain was associated with the likelihood of receiving analgesia. Almost all children reporting severe pain received analgesia (91.7%; 5846/6375), whereas only 39.0% (363/930) received analgesia where their initial pain severity was reported as mild. 4. Discussion This study reports on more than 15 000 children presenting to a single EMS over a 4-year period and identified 6 factors that were associated with the odds of children 14 years or younger achieving a pain score reduction of 2 or more points during their prehospital care. A pain score reduction of 2 points or more was considered clinically important and was likely to be associated with the patient experiencing the pain to Table 2 AORs of achieving clinically important pain reduction by analgesic agent (compared with no analgesic agent) Analgesic agent
Any analgesic Methoxyflurane Fentanyl Morphine
Eligible patients (n = 15 016) n (%)
AOR (95% CI)a
P
11 828 (78.8) 10 483 (69.8) 2480 (16.5) 996 (6.6)
6.6 (5.9-7.3) 5.3 (4.8-5.9) 2.8 (2.3-3.3) 2.8 (2.2-3.6)
b.001 b.001 b.001 b.001
a Adjusted model includes analgesic administered, analgesic agent, sex, case nature, case year, and initial pain score. Pseudo R2 for the model = 0.22.
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Table 3 AORs of achieving clinically important pain reduction by demographic factor and case nature
Age (y) 0-4 5-9 10-14 Sex Female Male Case Nature Medical Musculoskeletal Burns Poisoning Trauma other Cardiac Unknown Initial pain score category Mild (3) Moderate (4-7) Severe (8-10) Case year 2008 2009 2010 2011
AOR (95% CI)a
P
1 0.7 (0.6-0.95) 0.5 (0.4-0.6)
.020 b.001
1 1.1 (1.0-1.3)
.007
1 1.7 (1.5-1.9) 1.6 (1.1-2.5) 0.4 (0.2-0.8) 1.4 (1.1-1.9) 1.7 (0.9-3.1) 1.4 (1.0-1.8)
b.001 .017 .005 .012 .102 .028
1 3.9 (3.3-4.6) 7.5 (6.2-9.0)
b.001 b.001
1 1.3 (1.2-1.5) 2.0 (1.8-2.4) 2.0 (1.7-2.2)
b.001 b.001 b.001
a Adjusted model includes analgesic administered, analgesic agent, sex, case nature, case year, and initial pain score. Pseudo R2 for the model = 0.22.
be at least “a little better.” Overall, the cohort presented with severe pain (median VNRS, 7; IQR, 5-8) from a range of causes, predominately musculoskeletal injury. The majority achieved clinically important pain severity reduction (82.2%; 12346/15 016). Those who achieved pain reduction reported quite a substantial reduction (median VNRS reduction, 4; IQR, 2-6). Most of the children presenting with pain received an analgesic agent and, not surprisingly, those children who received any analgesic agent were 6.6 times more likely to report clinically important pain than those who were not. After adjusting for confounders, methoxyflurane had the strongest association with the clinically important reduction pain in children. Morphine and fentanyl had equivalent odds of reducing pain in children by 2 points or more. Methoxyflurane was the most commonly administered analgesic agent and was administered 10 times more often than intravenous morphine. One reported barrier to effective analgesia administration in children by paramedics [8] and emergency department staff [18] is the placement of an intravenous cannula due to concerns related to inflicting pain. This concern may at least partly explain the substantially lower use of parenteral analgesic agents in this cohort. It may be worth considering the addition of other enteral analgesic agents for those children where intravenous access is otherwise not required. Sublingual ketorolac or sublingual tramadol are 2 agents shown to be equally effective for pain management in children with suspected fractures or dislocations [19]. Children older than 9 years were the least likely to report a clinically important pain severity improvement. In fact, when compared with children 4 years or younger, each ascending age category was less likely to report clinically important pain reduction. It has been previously reported that age may be a factor in the experience of pain severity in the elderly [20], yet little has been reported for children. Male children were slightly more likely to achieve clinically important pain reduction than young females. Although more male children were administered an analgesic agent, this effect remained after adjusting for the administration of an analgesic agent. Sex differences have been reported as being associated with differences in the type of analgesia administered in the prehospital setting [21] and the severity of pain reporting [22]; however, to our knowledge, this is the first time that sex has been associated with the odds of achieving clinically important pain severity reduction in children.
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The more severe the initial report of pain, the greater the odds of achieving clinically important pain reduction. Those with an initial pain report of “severe” (VNRS 8-10) were 7.5 times more likely to achieve clinically important pain reduction than those reporting mild pain initially (VNRS 1-3). This is not a new phenomenon and has been previously reported in adults presenting to EMS with pain [23]. This may be related to the paramedics' willingness to treat pain based on their initial assessment of pain severity (through pain report and observed discomfort). In this cohort, more than 9 of 10 children who reported their initial pain as severe received analgesia, whereas less than 4 of 10 received analgesia where their initial pain was rated as mild. The type of pain categorized by case nature reported by the children was independently associated with the odds of achieving clinically important pain reduction. When compared with “other pain” which was predominantly of a medical etiology, children with musculoskeletal, burns, and other traumatic injuries had significantly greater odds of achieving clinically important pain reduction. Differences in the likelihood of achieving meaningful pain reduction in adults have also been reported, reporting that medical and “unknown” pain etiology has less odds of clinically meaningful pain reduction than pain of a traumatic nature [23]. It was clear in this population that the current treatment regime was not adequately managing pain of a medical etiology. One prehospital study reported that patients with traumatic injury were as likely to have their pain successfully managed as pain of other causes; however, the trauma group required larger doses of morphine [24]. Future research and audit should take these factors into account, targeting groups within the pediatric population which are at risk for inadequate analgesia. Older children and children with nontraumatic injury pose a distinct risk of poor pain management, and the barriers to effective pain management and most appropriate analgesic agents for this population require further investigation. 5. Limitations This retrospective study relies on ePCR data recorded by paramedics during or shortly after patient care. It is possible that errors of documentation or omission have occurred. Also, there was a large number (23.0%; 8779/38167) of cases that were missing either initial pain or final pain scores which were excluded prior to analysis. Finally, this study did not take into account the effect of any nonpharmacologic pain reduction strategies or the total doses of analgesic agents administered. 6. Conclusion This study provides new knowledge regarding factors associated with the management of pain in children. Despite few of the factors that have been shown to be independently associated with clinically important pain reduction being modifiable, they serve as characteristics of which clinicians and educators should focus attention. These factors should also inform strategies that aim to reduce barriers to effective management of pain in this vulnerable population.
Acknowledgments Removed to allow for blinded review. References [1] Turturro MA. Pain, priorities and prehospital care. Prehosp Emerg Care 2002;6(4): 486–8. [2] Thomas SH, Shewakramani S. Prehospital trauma analgesia. J Emerg Med 2008;35: 47–57. [3] Weisman SJ, Bernstein B, Schechter NL. Consequences of inadequate analgesia during painful procedures in children. Arch Pediatr Adolesc Med 1998;152(2):147–9. [4] Lavand'homme P. The progression from acute to chronic pain. Curr Opin Anaesthesiol 2011;24(5):545–50. [5] Voscopoulos C, Lema M. When does acute pain become chronic? Br J Anaesth 2010; 105(Suppl. 1):i69–85 [PubMed PMID: 21148657, Epub 2010/12/22. eng]. [6] Saxe G, Stoddard F, Courtney D, Cunningham K, Chawla N, Sheridan R, et al. Relationship between acute morphine and the course of PTSD in children with burns. J Am Acad Child Adolesc Psychiatry 2001;40(8):915–21 [PubMed PMID:11501691, Epub 2001/08/15. eng]. [7] Williams DM, Rindal KE, Cushman JT, Shah MN. Barriers to and enablers for prehospital analgesia for pediatric patients. Prehosp Emerg Care 2012;16(4): 519–26. [8] Watkins N. Paediatric prehospital analgesia in Auckland. Emerg Med Australas 2006; 18(1):51–6. [9] Australian Bureau of Statistics. 3218.0—Regional population growth, Australia, 201213. ‘Table 2: Estimated Resident Population, Statistical Areas Level 2, Victoria’. viewed 8 December 2014 http://wwwabsgovau/AUSSTATS/abs@nsf/DetailsPage/ 321802012-13?OpenDocument; 2014. [10] Ambulance Victoria. Ambulance Victoria 2011-2012 annual report. Doncaster: Ambulance Victoria; 2012. [11] Cox S, Martin R, McCabe N, Somaia P, Smith K. The development of a data-matching algorithm to define the ‘case patient’. Aust Health Rev 2013;37:54–9. [12] von Baeyer CL, Spagrud LJ, McCormick JC, Choo E, Neville K, Connelly MA. Three new datasets supporting use of the Numerical Rating Scale (NRS-11) for children's selfreports of pain intensity. Pain 2009;143(3):223–7. [13] Tomlinson D, von Baeyer CL, Stinson JN, Sung L. A systematic review of faces scales for the self-report of pain intensity in children. Pediatrics 2010;126(5): e1168–98. [14] Merkel S, Voepel-Lewis T, Malviya S. Pain assessment in infants and young children: the FLACC scale. Am J Nurs 2002;102(10):55–8. [15] Jennings PA, Cameron P, Bernard S. Measuring acute pain in the prehospital setting. Emerg Med J 2009;26(8):552–5. [16] Powell CV, Kelly AM, Williams A. Determining the minimum clinically significant difference in visual analog pain score for children. Ann Emerg Med 2001;37(1): 28–31 [PubMed PMID:11145767, Epub 2001/01/06. eng]. [17] Bulloch B, Tenenbein M. Assessment of clinically significant changes in acute pain in children. Acad Emerg Med 2002;9(3):199–202. [18] Babl FE, Mandrawa C, O'Sullivan R, Crellin D. Procedural pain and distress in young children as perceived by medical and nursing staff. Paediatr Anaesth 2008;18(5): 412–9. [19] Neri E, Maestro A, Minen F, Montico M, Ronfani L, Zanon D, et al. Sublingual ketorolac versus sublingual tramadol for moderate to severe post-traumatic bone pain in children: a double-blind, randomised, controlled trial. Arch Dis Child 2013; 98(9):721–4. [20] Gibson SJ, Helme RD. Age-related differences in pain perception and report. Clin Geriatr Med 2001;17(3):433–56. [21] Lord B, Cui J, Kelly A-M. The impact of patient sex on paramedic pain management in the prehospital setting. Am J Emerg Med 2009;27:525–9. [22] Paller CJ, Campbell CM, Edwards RR, Dobs AS. Sex-based differences in pain perception and treatment. Pain Med 2009;10(2):289–99. [23] Jennings PA, Cameron P, Bernard S. Determinants of clinically important pain severity reduction in the prehospital setting. Emerg Med J 2012;29(4):333–4. [24] Ricard-Hibon A, Belpomme V, Chollet C, Devaud ML, Adnet F, Borron S, et al. Compliance with a morphine protocol and effect on pain relief in out-of-hospital patients. J Emerg Med 2008;34:305–10.
Contents lists available at ScienceDirect
American Journal of Emergency Medicine journal homepage: www.elsevier.com/locate/ajem
Original Contribution
Clinically meaningful reduction in pain severity in children treated by paramedics: a retrospective cohort study Paul A. Jennings, PhD a,b,c,⁎, Bill Lord, PhD d, Karen Smith, PhD b,e,f a
Department of Community Emergency Health and Paramedic Practice, Monash University, Caulfield East, Victoria, Australia Ambulance Victoria, Doncaster, Victoria, Australia Emergency & Trauma Centre, The Alfred Hospital, Melbourne, Victoria, Australia d School of Nursing, Midwifery and Paramedicine, University of the Sunshine Coast, Sippy Downs, Queensland, Australia e Department of Epidemiology and Preventive Medicine, Monash University, Melbourne, Victoria, Australia f Discipline–Emergency Medicine, University of Western Australia, Crawley, Western Australia, Australia b c
a r t i c l e
i n f o
Article history: Received 21 April 2015 Received in revised form 15 June 2015 Accepted 16 June 2015
a b s t r a c t Introduction: Pediatric pain is a common presenting symptom in the prehospital setting; however, there is a lack of data identifying factors associated with effective pain management in this population. We sought to identify the factors associated with clinically meaningful pain reduction in children. Methods: An analysis of electronic patient care records of all patients younger than 15 years presenting with pain to the emergency medical service of Victoria, Australia, over a 4-year period (2008-2011). Data were analyzed using descriptive statistics and multivariate regression to assess predictors of clinically meaningful pain reduction. Clinically meaningful pain reduction was defined as a reduction of 2 or more points on an 11-point scale. Results: A total of 92378 children were transported, of whom 15016 (16.3%) met the inclusion criteria. The median age was 11 (interquartile range, 9-13) years, and 59.2% were male. Patients older than 9 years were less likely (adjusted odds ratio [AOR], 0.5; 95% confidence interval [CI], 0.4-0.6) and boys were more likely (adjusted odds ratio, 1.1; 95% CI, 1.0-1.3) to have a clinically meaningful reduction in pain. Patients with pain classified as musculoskeletal were more likely to achieve a reduction in pain score of 2 or more when compared with pain due to other medical causes (AOR, 1.7; 95% CI, 1.5-1.9). Conclusions: Factors other than the type of analgesia are important determinants of prehospital pain relief and are likely to impact on clinical care and research. Clinical audit and research projects should stratify patients according to patient as well as management factors to maximize service improvement. © 2015 Elsevier Inc. All rights reserved.
1. Introduction Exposure to children with pain is very common in the prehospital and emergency setting. Despite being a frequent presentation, there is limited evidence regarding factors associated with the likelihood of a clinically meaningful reduction in pain severity in the paramedic practice setting. Early, effective pain management in both the emergency medical service (EMS) and emergency department settings is an important component of care and may play a role in reducing the likelihood of chronic pain syndromes and pain-related anxiety and posttraumatic stress after the acute phase [1–6]. Paramedics generally have a range of pharmacologic and nonpharmacologic pain management strategies available. An ability to identify demographic, injury, and management factors that are associated with the likelihood of successfully achieving clinically important pain reduction is important to clinicians. Knowledge of factors which improve or inhibit the likelihood of clinically important pain reduction ⁎ Corresponding author at: Monash University, Building C (503), Level 4, 900 Dandenong Rd, Caulfield East, VIC 3145, Australia. Tel.: +61 3 9904 4264. E-mail address: [email protected] (P.A. Jennings). http://dx.doi.org/10.1016/j.ajem.2015.06.026 0735-6757/© 2015 Elsevier Inc. All rights reserved.
in children allows the clinician to focus their attention on strategies to optimize their pain management plan. Barriers to adequate analgesia administration have been previously reported in the provision of analgesia to both adults and children [7,8]. Qualitative studies have suggested that paramedics decision making around the provision and type of analgesia to be administered can be influenced by the patients' age [8], concern of adverse effects, organizational norms and beliefs about opioids, and provider knowledge of pediatric parenteral analgesia options [7]. This study aims to identify the factors associated with the clinically meaningful reduction in pain severity in children who were treated by paramedics in a busy EMS.
2. Methods 2.1. Study design This retrospective cohort study analyzed pediatric patients 14 years or younger who were treated and transported by paramedics in Victoria, Australia, between January 1, 2008, and December 31, 2011.
1588
P.A. Jennings et al. / American Journal of Emergency Medicine 33 (2015) 1587–1590
Ethics Committee approval was received by the Monash University Human Research Ethics Committee (A/12/383), and access to deidentified patient data was approved by Ambulance Victoria.
measure was the proportion of patients with a clinically meaningful reduction in pain severity defined as a pain rating reduction of 2 or more points on an 11-point VNRS.
2.2. Study population and setting
3. Results
Ambulance Victoria is the sole statewide provider of emergency ambulance services for a population of approximately 5.5 million people in a region that covers more than 227 000 km2, with more than 4.3 million residing in metropolitan Melbourne [9]. Paramedics responded to approximately 800 000 incidents in 2001 [10], resulting in 360 766 patients being transported. Pediatric patients represented 7.1% (n = 25 563) of this caseload. The scope of practice for paramedics used in this jurisdiction includes inhaled methoxyflurane, parenteral morphine sulphate or fentanyl according to clinical practice guidelines. There are no age restrictions placed on the administration of opioids, the drugs are indicated for pain of any cause, and medical consultation is not required. Fentanyl via the intranasal route was added to the pain management guideline for children in 2009. All patient-level data are collected via an in-field electronic patient care record (ePCR) system (VACIS, VACIS Collaboration, Melbourne). Paramedics enter scene findings, patient demographic data, clinical observations, and treatment data directly into the ePCR both during and after the episode of care. Clinical, administrative, and operational data are then maintained in a data warehouse [11]. Paramedics use several pain severity rating scales in this setting, most commonly the verbal numeric rating scale (VNRS), which is an 11-point scale whereby the patient is required to rate their pain severity between 0 and 10, with 0 meaning no pain and 10 the worst pain imaginable [12]. In young children, the Wong-Baker Faces pain scale is used to assess pain severity, and the Face, Legs, Activity, Cry, Consolability scale is recommended for pain assessment in infants and preverbal children [13,14]. Where that patient has difficulty in reporting a numerical rating, paramedics may record an adjective to rate the pain [15]. The adjective is subsequently converted to a numeric pain severity rating, where “none” represents 0; “mild, ”2; “moderate, ” 5; and “severe,” 8. Clinically meaningful pain reduction was defined as a final pain severity score recorded on VACIS as 2 or more less than the initial pain severity score. A reduction of 2 or more was selected, as a visual analog pain score reduction of 10 mm in children has been previously shown to be the minimum clinically significant difference whereby a patient is likely to report feeling “a bit better” or “a bit worse” [16]. Another study reported a reduction of 2 points was required for a child to recognized a difference in pain severity [17]. Cases were included if the patient was transported between January 1, 2008, December 31, 2011; the patient was younger than 15 years; “pain” was recorded in secondary survey, assessment, or patient complaint field; or a pain score higher than 0 was reported at any time during care. Cases were excluded if the initial or final pain score was missing, or the initial pain score was less than 3.
During the study period, January 1, 2008, December 31, 2011, 92 378 children aged less than 15 years had an ambulance dispatched and AV paramedics attend, 38 167 (41.3%) of which reported pain at any time after ambulance arrival. Of the children presenting with pain, 23 151 (60.6%) were excluded based on study criteria (Figure). This left 15 016 children for inclusion in the analysis. The demographics of those who achieved and did not achieve clinically meaningful pain severity reduction are provided in Table 1. Of the 15 016 children who were attended by paramedics with an initial pain score greater than 3 and available initial and final pain scores, 12 346 (82.2%) of 15 016 achieved clinically important pain reduction. Most of the children presenting with a VNRS of 3 or greater were male (60.7%) and aged between 10 and 14 years (70.2%). The median time to first analgesia was 11 minutes (interquartile range [IQR], 9-13 minutes), and there was little difference between those who achieved clinically important pain reduction and those who did not. The etiology of the children's pain was assigned a category based on the paramedic's assessment of case nature and is presented in Table 1, categorized by pain severity improvement. Musculoskeletal injury was the most common case nature encountered in this cohort (74.2%). The group of children who achieved clinically important pain severity reduction presented with a higher median (IQR) initial pain score than the group who did not (7 [5-8] vs 5 [4-7]; P b .001; Table 1). Most of the children with pain (78.8%) received an analgesic agent (either methoxyflurane or morphine sulphate or fentanyl). A small number (3.8%; 575/15 016) of children (or their parents/guardians) were reported to have refused the offer of analgesia, and paramedics reported withholding analgesia when indicated in 1.0% (147/15 016) of cases, which is most often due to contraindications. Inhaled methoxyflurane was the most common agent administered to children reporting pain (69.8%; 10 483/15016), followed by intranasal or intravenous fentanyl (16.5%; 2480/15 016) and intravenous morphine (6.6%; 996/ 15 016). More male than female children received an analgesic agent (79.8% vs 77.1%; P b .001). The odds of achieving clinically significant pain reduction was more than 6 times greater in children who received analgesia when compared with those who did not (adjusted odds ratio [AOR], 6.6; 95% CI, 5.9-7.3). Of all the analgesic agents, methoxyflurane was associated with the greatest odds of achieving clinically important pain reduction (AOR, 5.3; 95% CI, 4.8-5.9; Table 2).
Considered for inclusion N = 92,378
2.3. Statistical analysis Descriptive statistics and logistic regression were used to test the association between clinically meaningful pain reduction and the independent variables. The χ 2 test was used to test associations between categorical variables and the Wilcoxon rank sum test for associates between continuous variables that were not normally distributed. The independent variables used in the multivariate regression analysis were age, sex, pain cause, initial pain score, administration of any analgesia, and case year and were selected as univariate analysis indicated that they were statistically associated with the dependent variable at the .05 significance level. Odds ratios and their associated 95% confidence intervals (CIs) were calculated. All statistical analyses were considered to be significant at the .05 level. Stata Statistical Version 12 (StataCorp, College Station, TX) was used for data analysis. The primary outcome
• Did not meet inclusion criteria =54,211 • Initial Pain Score < 3 = 14,372 • Initial OR final Pain Score not available = 8,779 Total N = 77,362
Final cases included in analysis N = 15,016
Figure. Flowchart for included patients.
P.A. Jennings et al. / American Journal of Emergency Medicine 33 (2015) 1587–1590 Table 1 Characteristics of children by pain improvement Characteristic
Age (y), median (IQR) Age, n (%) 0-4 y 5-9 y 10-14 y Sex, n (%) Female Male Case nature (musculoskeletal), n (%) Other (including medical cause) Unknown Trauma other Burns Poisoning Cardiac Time to first analgesia (min), median (IQR)b Pain score, median (IQR) Initial pain Final pain Pain difference
No clinically meaningful improvement (n = 2670) 12 (10-13)
Clinically Total meaningful (n = 15 016) improvement (n = 12 346)
Pa
11 (9-13) b.001
11 (9-13)
114 (4.3) 540 (20.2) 408 (75.5)
644 (5.2) 3182 (25.7) 8520 (69.0)
758 (5.0) 3722 (24.8) 10 536 (70.2)
b.001
2016 (42.8) 1526 (57.2) 1572 (58.9)
4764 (38.6) 7582 (61.4) 9578 (77.6)
5908 (39.3) 9108 (60.7) 11 150 (74.2)
b.001
820 (30.7)
1711 (13.9)
2531 (16.9)
101 (3.8) 87 (3.3) 36 (1.4) 33 (1.2) 21 (0.8) 6 (3-12)
342 (2.8) 338 (2.7) 306 (2.5) 23 (0.2) 48 (0.4) 4 (2-7)
443 (3.0) 425 (2.8) 342 (2.3) 56 (0.4) 69 (0.4) 4 (3-7)
5 (4-7) 5 (4-7) 0 (0-1)
7 (5-8) 2 (1-3) 5 (3-6)
7 (5-8) 2 (1-4) 4 (2-6)
b.001
b.001
b.001 b.001 b.001
a
Association between no clinically important pain reduction and clinically important pain reduction. b Time interval between patient access by the paramedic and time of first analgesic administration.
The odds of achieving clinically important pain reduction were also associated with other patient characteristics. Children aged 5 to 9 years (AOR, 0.7; 95% CI, 0.6-0.95) and aged 10 to 14 years (AOR, 0.5; 95% CI, 0.4-0.6) had less odds of achieving clinically important pain reduction than their young (b3 years) counterparts. Boys had slightly greater odds than girls of experiencing clinically important pain reduction (AOR, 1.1; 95% CI, 1.1-1.3). Case nature was also associated with the odds of achieving clinically important pain reduction. The initial pain severity reported by children was a strong independent predictor of the odds of achieving clinically important pain reduction. Those with more severe pain were more likely to have their pain relived (Table 3). Furthermore, more severe pain was associated with the likelihood of receiving analgesia. Almost all children reporting severe pain received analgesia (91.7%; 5846/6375), whereas only 39.0% (363/930) received analgesia where their initial pain severity was reported as mild. 4. Discussion This study reports on more than 15 000 children presenting to a single EMS over a 4-year period and identified 6 factors that were associated with the odds of children 14 years or younger achieving a pain score reduction of 2 or more points during their prehospital care. A pain score reduction of 2 points or more was considered clinically important and was likely to be associated with the patient experiencing the pain to Table 2 AORs of achieving clinically important pain reduction by analgesic agent (compared with no analgesic agent) Analgesic agent
Any analgesic Methoxyflurane Fentanyl Morphine
Eligible patients (n = 15 016) n (%)
AOR (95% CI)a
P
11 828 (78.8) 10 483 (69.8) 2480 (16.5) 996 (6.6)
6.6 (5.9-7.3) 5.3 (4.8-5.9) 2.8 (2.3-3.3) 2.8 (2.2-3.6)
b.001 b.001 b.001 b.001
a Adjusted model includes analgesic administered, analgesic agent, sex, case nature, case year, and initial pain score. Pseudo R2 for the model = 0.22.
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Table 3 AORs of achieving clinically important pain reduction by demographic factor and case nature
Age (y) 0-4 5-9 10-14 Sex Female Male Case Nature Medical Musculoskeletal Burns Poisoning Trauma other Cardiac Unknown Initial pain score category Mild (3) Moderate (4-7) Severe (8-10) Case year 2008 2009 2010 2011
AOR (95% CI)a
P
1 0.7 (0.6-0.95) 0.5 (0.4-0.6)
.020 b.001
1 1.1 (1.0-1.3)
.007
1 1.7 (1.5-1.9) 1.6 (1.1-2.5) 0.4 (0.2-0.8) 1.4 (1.1-1.9) 1.7 (0.9-3.1) 1.4 (1.0-1.8)
b.001 .017 .005 .012 .102 .028
1 3.9 (3.3-4.6) 7.5 (6.2-9.0)
b.001 b.001
1 1.3 (1.2-1.5) 2.0 (1.8-2.4) 2.0 (1.7-2.2)
b.001 b.001 b.001
a Adjusted model includes analgesic administered, analgesic agent, sex, case nature, case year, and initial pain score. Pseudo R2 for the model = 0.22.
be at least “a little better.” Overall, the cohort presented with severe pain (median VNRS, 7; IQR, 5-8) from a range of causes, predominately musculoskeletal injury. The majority achieved clinically important pain severity reduction (82.2%; 12346/15 016). Those who achieved pain reduction reported quite a substantial reduction (median VNRS reduction, 4; IQR, 2-6). Most of the children presenting with pain received an analgesic agent and, not surprisingly, those children who received any analgesic agent were 6.6 times more likely to report clinically important pain than those who were not. After adjusting for confounders, methoxyflurane had the strongest association with the clinically important reduction pain in children. Morphine and fentanyl had equivalent odds of reducing pain in children by 2 points or more. Methoxyflurane was the most commonly administered analgesic agent and was administered 10 times more often than intravenous morphine. One reported barrier to effective analgesia administration in children by paramedics [8] and emergency department staff [18] is the placement of an intravenous cannula due to concerns related to inflicting pain. This concern may at least partly explain the substantially lower use of parenteral analgesic agents in this cohort. It may be worth considering the addition of other enteral analgesic agents for those children where intravenous access is otherwise not required. Sublingual ketorolac or sublingual tramadol are 2 agents shown to be equally effective for pain management in children with suspected fractures or dislocations [19]. Children older than 9 years were the least likely to report a clinically important pain severity improvement. In fact, when compared with children 4 years or younger, each ascending age category was less likely to report clinically important pain reduction. It has been previously reported that age may be a factor in the experience of pain severity in the elderly [20], yet little has been reported for children. Male children were slightly more likely to achieve clinically important pain reduction than young females. Although more male children were administered an analgesic agent, this effect remained after adjusting for the administration of an analgesic agent. Sex differences have been reported as being associated with differences in the type of analgesia administered in the prehospital setting [21] and the severity of pain reporting [22]; however, to our knowledge, this is the first time that sex has been associated with the odds of achieving clinically important pain severity reduction in children.
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The more severe the initial report of pain, the greater the odds of achieving clinically important pain reduction. Those with an initial pain report of “severe” (VNRS 8-10) were 7.5 times more likely to achieve clinically important pain reduction than those reporting mild pain initially (VNRS 1-3). This is not a new phenomenon and has been previously reported in adults presenting to EMS with pain [23]. This may be related to the paramedics' willingness to treat pain based on their initial assessment of pain severity (through pain report and observed discomfort). In this cohort, more than 9 of 10 children who reported their initial pain as severe received analgesia, whereas less than 4 of 10 received analgesia where their initial pain was rated as mild. The type of pain categorized by case nature reported by the children was independently associated with the odds of achieving clinically important pain reduction. When compared with “other pain” which was predominantly of a medical etiology, children with musculoskeletal, burns, and other traumatic injuries had significantly greater odds of achieving clinically important pain reduction. Differences in the likelihood of achieving meaningful pain reduction in adults have also been reported, reporting that medical and “unknown” pain etiology has less odds of clinically meaningful pain reduction than pain of a traumatic nature [23]. It was clear in this population that the current treatment regime was not adequately managing pain of a medical etiology. One prehospital study reported that patients with traumatic injury were as likely to have their pain successfully managed as pain of other causes; however, the trauma group required larger doses of morphine [24]. Future research and audit should take these factors into account, targeting groups within the pediatric population which are at risk for inadequate analgesia. Older children and children with nontraumatic injury pose a distinct risk of poor pain management, and the barriers to effective pain management and most appropriate analgesic agents for this population require further investigation. 5. Limitations This retrospective study relies on ePCR data recorded by paramedics during or shortly after patient care. It is possible that errors of documentation or omission have occurred. Also, there was a large number (23.0%; 8779/38167) of cases that were missing either initial pain or final pain scores which were excluded prior to analysis. Finally, this study did not take into account the effect of any nonpharmacologic pain reduction strategies or the total doses of analgesic agents administered. 6. Conclusion This study provides new knowledge regarding factors associated with the management of pain in children. Despite few of the factors that have been shown to be independently associated with clinically important pain reduction being modifiable, they serve as characteristics of which clinicians and educators should focus attention. These factors should also inform strategies that aim to reduce barriers to effective management of pain in this vulnerable population.
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