Pre-hospital analgesia in pediatric trauma and critically ill patients: An analysis of a German air rescue service

The treatment of pain in pre-hospital pediatric emergencies continues to be a major challenge. In recent years, numerous studies have been conducted on this topic and the results have revealed that pre-hospital pain management in children is restrained and mostly inadequate [1‐7]. Several best-practice guidelines have made recommendations for better pre-hospital pain management in children and recognized the need to make this a prioritized research topic [8‐11]. The treatment of acute pain conditions is an elementary task of any emergency medical service (EMS). Pain therapy is particularly demanding in children because age, developmental stage, cognitive ability and communication skills must be taken into account [12]. Pre-hospitally, numerous measures are available to relieve pain, including non-pharmacological measures such as splinting, bandaging and cooling. If the pain is more severe, analgesia with medication is indicated; analgesics with varying degrees of effectiveness are always available for this purpose. Furthermore, many principles of pain management from existing recommendations for adults may also well apply to children. Inadequate pain management can have serious short and long-term consequences: Anxiety, fear of further medical treatment, post-traumatic stress disorder, development of chronic pain, and poorer recovery outcomes [13‐16]. Several research groups have tried to identify risk factors for poor pain management in children: age < 5 years and short care time have been reported clustered causal factors for poor pain management [4, 17, 18]. Even in children with severe pain, it has been repeatedly shown that children have not received adequate pain management [6]. The reasons for these results are manifold; as recently reported also the lack of training and skills (e.g. iv line), dosage uncertainties, fears of adverse effects (e.g. bradypnea) and the missing routine caused by the rarity of pediatric emergencies seem to cause major problems [19, 20].

In Germany, there have been no studies on the quality of pain therapy in the pre-hospital period in childhood. However, a few studies from all over the world clearly show that there are deficits in pediatric pain therapy in the emergency medical service (EMS) and that this topic should be given more attention in scientific studies, especially in a physician staffed EMS.

The objective of this study was to evaluate the management of acute pain in children in the pre-hospital setting. This study analyzed the assessment of pain in children and the effectiveness of the analgetic treatment by emergency physicians with reference to etiology of pain and pain severity.

Each EMS mission is documented in a standardized online-database (HEMSDER-Database, Convexis, Germany). The collected data includes basic patient demographics as well as diagnostical and therapeutical actions of the emergency physician on scene. The severity of pain is assessed on a 0 (no pain) to 10 (maximum of pain) scale and was collected twice: First at arrival of the emergency physician on scene and second at admission to hospital.

Various analgesics are available on the helicopters, including the opioids fentanyl, sufentanil, piritramide and morphine. Ketamine and various non-opioid analgesics, like non-steroidal anti-inflammatory drugs (NSAID), are also available. All analgesics can be administered at the discretion of the emergency physician.

In the retrospective study period from 2012 to 2020 all emergency medical missions of DRF helicopters were included. Furthermore, we defined children with ages ranging from 0—16 years. The Glasgow Coma Scale (GCS) was used to distinguish between awake and anaesthetized patients. Patients with a GCS 3 at hospital admission were excluded from the study because a GCS3 is associated with general anesthesia, therefore we excluded these patients from the analysis. Furthermore, patients were excluded if the documentation was incomplete in relevant variables (e.g. missing vital signs). Based on the major diagnosis the cases were divided into a trauma and a non-trauma (e.g. acute abdomen) group. Patients with both, trauma and non-trauma, were excluded from further analyses. A value of > 4 in NRS was regarded as being moderate-to-severe pain and analyzed more in detail. The primary outcome measure was effective pain management, defined as a reduction of >  = 2 points on the NRS. Secondary outcomes were the analysis of the given pain medication.

For the descriptive analysis of numerical variables, the mean and standard deviation were computed, for categorial and dichotomous variables the frequency and proportion in percent were calculated. For comparative analysis Mann–Whitney-U or Chi-Quadrat-test (respectively Fisher´s exact test for small sample sizes) were used if applicable. Tests were two sided. A p-value of 0.05 or less was considered statistically significant. Calculations were performed with IBM SPSS Statistics 26 (Armonk, NY, USA).

The study was approved by the Ethics Committee of the Christian-Albrechts-Universität Kiel (registration: D 424/22) and registered in the German Register of Clinical Studies (Trial registration: DRKS 00,026,222).

This study evaluated 20,405 pediatric emergencies with 12,000 children being affected by trauma and 8,108 children with acute pain due to non-trauma. 4,608 (38.4%) children with trauma had a NRS > 4 at first survey (mean 6.9 (SD 1.5)). Children with acute pain due to non-trauma were less likely to have moderate to high pain scores (3.5%) but if relevant pain was present (NRS > 4), it tended to be severe (mean NRS 6.7 (SD 1.5)) (Table 1). Surprisingly, analgetic treatment differed significantly despite similar NRS regarding trauma and acute pain due to non-trauma. Thus, children in the trauma group received opioids in 62.0% and ketamine in 34.5%. In the non-trauma group opioids (35.8%) and ketamine (2.8%) were administered significantly less frequent and paracetamol and metamizole were given instead.

Over the past decade, numerous recommendations have been published on pre-hospital pain management in children [10], which have not yet found widespread implementation. Different drugs for analgesia have been suggested and recommended depending on the severity of the pain. But this also raises the question which analgesics are available in the different ambulance systems and how experienced the users are with possible application routes (e.g. intravascular, nasal or intramuscular). For management of moderate to severe pain, fentanyl appears to be the first line treatment for children [10, 28]. In our study, fentanyl was primarily used for analgesia, with piritramide being the second most commonly opioid used. The results of our study show a trend towards restrained use of opioids in young children and an increase in opioid administration in children older than 6 years, these results are consistent with a recent study by Rugg et al. [29]. In children with an initial NRS > 4, an opioid was administered in 62% of all cases. In toddlers and infants with severe pain, ketamine is the most commonly used analgesic. We assume that there is a greater uncertainty in the treatment of younger children, especially regarding the side effects of opioids. Thus, it indeed seems convincing to rather use ketamine due to its lower side effect profile and/or to apply opioids intranasally with the aim of achieving a greater therapeutic breadth [28, 30, 31]. From the age of 6 years, opioids are more often administered for analgesia and the use of ketamine becomes less frequent.

The comparison of the trauma and the non-trauma group showed a lower NRS in trauma children at the time of hospital admission (mean NRS 1.9) than in children with non-trauma (mean NRS 2.7). When NSAID mono therapy or even no analgesics were administered, the results were poor: 10.4% NSAID resp. 15.7% (no analgesics) of the patients reported NRS > 4 at hospital admission (Table 2). Around 9,4% of all children with trauma and a total of 28,4% in the non-trauma group with NRS > 4 received no pain medication at all.

We consider these numbers to be worrying because they clearly reflect uncertainty in the treatment of children. We can only speculate about the causes of the inadequate pain therapy in our setting, as all emergency physicians on our helicopters are required to have expertise in pediatric analgetic treatment. However, our findings are consistent with those of many other studies that have drawn attention to inadequate pain management for children in emergency medicine worldwide. Another study of pre-hospital analgesia found that although pain was noted in 446 cases, analgesia was administered in only 3.3% [2]. In one Canadian study, children with fractures of the extremities received analgesia in 37%, but only 3.2% received opioids [3]. Lord et. al also reported that in the case of the most severe pain (NRS 8–10), only 45% of children received analgesia [6]. According to these findings, children are at comparatively high risk for inadequate pre-hospital analgesia. A comparison of the studies is difficult as the ambulance systems in the different countries are not necessarily identical and a distinction must be made between physician and non-physician care. We believe that the more appropriate pain management in our study compared to most other studies is related to the fact that an emergency physician (trained in pediatric emergencies) was always involved.

Murphy et al. describe possible reasons such as communication problems in infants and young children, inadequate training of emergency personnel, and uncertainty and lack of experience in the assessment and care of children [21]. Paramedics and physicians are trained in providing and treating children, but pediatric emergencies occur less frequently, and invasive procedures and therapies are rarely needed. Reluctance associated with placing intravenous access in children appears to be a significant concern for paramedics and physicians, leading to hesitation and ultimately contributing to lower administration of analgesics [17].

The difficulty of correctly assessing pain in children has been cited as another potential cause of inadequate pain management in children. The major problem in pain assessment appears to be subjectivity and finding an adequate scale for the age. In our study, NRS was reported for almost all children, which is possibly due to the electronic patient report form used, in which two documented NRS scores are mandatory, one at first contact on scene and one at hospital admission. A large proportion of our patients were younger than 8 years, limiting the applicability of the NRS. Certainly, some children were unable to assign a number to their pain, e.g. depending on their common status. Presumably, the reported value in these patients corresponded to the personal impression of the emergency physician. It remains unclear whether in some cases other scores were additionally collected but not documented. In several studies the NRS was validated in children aged 8 + years [22]. The minimal clinically relevant difference in the numerical rating scale is 2 points on a 10- point scale [23, 24]. Other authors define effective analgesia as a reduction in pain score by at least 30% [25]. In our study population, an effective reduction in pain (> = 2 scale points) was achieved in 95.9% for pediatric trauma and resp. 86.3% for children in the non-trauma group (Table 3).

For children, there are further scales according to their age, including the Wong-Baker faces scale, on which children are asked to select the face that best represents their pain; this scale has been validated from the age of 3 years [26]. The Children´s Discomfort and Pain Scale according to Büttner is used for pain assessment in children from neonatal age to the age of four and has been validated for postoperative pain [27]. To our knowledge, there are no validated pain scoring systems for children in the pre-hospital setting and there is no requirement at DRF to use one specific scoring method. Nevertheless, we are convinced that the common scales are also suitable for the assessment of pain in the pre-hospital setting. Furthermore, the available data show that the pain scale used reliably reflects the treatment success.

Overall, the results show that a sufficient pain therapy could be achieved especially in patients with NRS > 4. Children with trauma received more pain medication than in the context of non-trauma, even if the pain was comparably severe. In Germany the most common analgesic medications administered were ketamine and fentanyl, followed by piritramide. Ketamine was given more frequently to children under 6 years of age, while opioids were given more frequently with increasing age. To further improve sufficient pain management in children and reduce anxiety, dosing tools should be available in all settings and regular training with them should be provided.