Pain is defined as ‘an unpleasant sensory and emotional experience associated with actual or potential tissue damage’ (International Association for the Study of Pain, 1994). The British Pain Society (2019) extends this a step further by stating that ‘pain is an emotion…’, and that ‘pain can be perceived as a warning of potential damage, but can also be present when no actual harm is being done to the body’.
The management of pain is complex—especially in children—as age, developmental level, cognitive and communication skills, and associated beliefs, must be considered (Srouji et al, 2010) Without effective pain treatment, children may suffer long-term physiological (e.g. stress hormone responses) or psychological (e.g. pain perception) changes (Finley et al, 2005), and are at risk of developing post-traumatic stress disorder (PTSD) (Saxe et al, 2001; Sheridan et al, 2014).
This comment aims to illustrate and discuss the complexity of the pain management process for children in the prehospital setting. We acknowledge the difficulty in defining the age range of ‘children’ (Whitley and Lord, 2018), but will consider the age of a child to be <18 years. Development of the process map illustrated in Figure 1 was based on existing literature, expert opinion and clinical experience.
Theory of pain
Fundamental to understanding the process of prehospital pain management in children is an appreciation of pain theory. A number of theories seek to explain the complex phenomenon of pain—the best known being Melzack and Wall (1965), who proposed gate control theory, which is widely accepted and combines earlier concepts of specificity and pattern theory.
Gate control theory of pain
Gate control theory (Melzack and Wall, 1965) explains that pain is controlled by a ‘gate’, where certain factors will either open or close the gate. This theory accepts the disparity between pain stimuli and pain perception, with psychological (e.g. previous experience of pain, level of concentration, and emotion) and physical (e.g. non-painful stimuli such as rubbing/vibration) factors influencing the ‘gate’, subsequently affecting the amount of pain perceived.
Having understood gate control theory, it is thereby possible to discuss the four main facets of the prehospital pain management process in children, as shown in Figure 1.
Illness/injury causing pain
Typically, within the prehospital setting, cause of pain is categorised as either trauma or medical. For example, a child may present with a fracture, sustain a burn injury or have a laceration to the skin. These would all be classified as ‘traumatic’ injuries. They influence the child's perception of pain as the child may have experienced an injury and may visually see the abnormality, perhaps a deformed limb or the presence of blood, in addition to feeling the pain. This differs to medical pain caused by headache or abdominal pain, for example, as the child cannot visually see any abnormality; they can only feel the pain.
Children in these different subgroups may have varying perceptions of pain. A child may be more likely to self-soothe or rub the site of a medical cause of pain, such as abdominal pain or growing pains, than they would traumatic pain from a burn or broken limb for example. This could be explained by gate control theory (Melzack and Wall, 1965), as non-painful stimuli such as rubbing ‘closes’ the gate, reducing perceived pain.
Different aetiologies also affect the clinician's perception. For instance, we know that children who suffer traumatic pain versus medical pain are more likely to receive effective pain management (Bendall et al, 2011; Jennings et al, 2015; Lord et al, 2017); therefore, the aetiology of pain is an important consideration.
Child's perception of pain
The child's perception of pain is likely to be influenced by many factors, including the child's developmental level and cognitive ability, their prior experience of pain, the reaction of the people around them (friends and/or family) and the appearance of the illness/injury as discussed. Prior experience has a significant potential to influence pain perception; pain can therefore be considered a ‘learned’ phenomenon. However, as each child's prior experience will differ, so will their perception and resultant behaviour. Clinicians should interpret behaviour with caution when assessing pain.
The culture and belief system of the child is important to consider. For example, some cultures (Givler and Maani-Fogelman, 2019) believe pain to be beneficial; it is viewed in a positive light rather than a negative one, as pain prevents further injury and promotes self-splinting. Paramedics in Japan, for example, do not carry analgesics (Igarashi et al, 2018), illustrating this alternative culture around pain. The environment (e.g. hot, cold, crowded, calm), in which the child experiences pain, along with their emotional state is likely to influence pain perception.
The assessment and management of pain by the clinician also influences the overall perception of pain by the child. As an example, when a child is suffering abdominal pain, the clinician may perform an abdominal assessment which will involve palpation. This may influence the perception of pain by increasing or decreasing its intensity. Also, the child may experience heightened states of emotion such as fear and anxiety during assessment, potentially changing the perception of pain by the child. Interventions such as analgesics and non-pharmacological techniques including slings and splints, distraction techniques and comfort, may also influence the perception of pain.
Ambulance clinician assessment of pain
The clinician's assessment of pain is influenced by prior clinical experience of assessing pain in children, education and training, the priority of the pain within the clinical situation, and the level of communication of the patient, the parent/guardian and the clinician. If, for example, a child was suffering hypovolaemic shock from an amputated limb, the highest priority would be to stop the bleeding and reverse the shock. Therefore, pain assessment would be less of a priority in this situation. However, communication is a significant factor during the assessment of pain. The clinician should be able to communicate effectively with the child or parent/guardian, and the child should be able to communicate effectively with the clinician or parent/guardian. Where communication is not an option (e.g. preverbal, poor cognitive function), clinicians must rely on behavioural pain scales such as FLACC [Face, Legs, Activity, Cry, Consolability] (Brown et al, 2016; Whitley, 2018).
Communication can be challenging, especially when a prehospital clinician may not have sufficient education and training in paediatric prehospital care, or is not exposed to children frequently from a social/family life perspective, or in a professional capacity. Lord et al (2017) reports a 7.1% incidence of children (patients <15 years) and Shah et al (2008) reports a 13% incidence of children (patients <19 years).
The clinician's assessment of pain is influenced by the child's perception, the source of pain and the clinician's initial management of pain. If the child has suffered multiple injuries in the past or has previously suffered cancer and undergone chemotherapy, for example, it is likely that their perception of pain may be different to that of a child experiencing pain for the first time (Cafasso, 2018). This may result in a higher or lower pain score when using objective tools.
Ambulance clinician management of pain
Pain management is influenced not only by the level of education and training, and scope of practice, of the clinician, but also how empathetic they are, their culture and belief system, their emotional state, prior experience of managing pain in children, parental approval, compliance of the child and the relative distance to hospital.
Qualitative research has found that one of the barriers to effective pain management in children is fear perceived by the clinician (Williams et al, 2012). Clinicians fear children having an allergic reaction to morphine, for example. Murphy et al (2014) found that another barrier was inhaled analgesics, as they are difficult to administer to distressed and uncooperative children.
The clinician's management of pain is influenced by the child's perception of pain, the clinician's assessment of the pain and the type of pain. Lord et al (2016) found that clinicians were significantly more likely to administer analgesia to children suffering traumatic pain versus medical pain, those with a high initial pain score versus no pain, male children versus female children, and children who were older (3+ years) versus younger (<3 years).
Conclusion
Prehospital pain management in children is extremely complex and multifaceted, with many influencing factors. Individual single-component strategies to improve pain management in this area are unlikely to have a significant impact, whereas multiple strategies or multifaceted strategies are more likely to succeed. Further research is required to explore the associations and influencing factors within this process map.