The Hazardous Area Response Team (HART) consists of specially trained paramedics—and in some trusts, ambulance service technicians—who deliver clinical care in potentially dangerous environments to increase survival rates and improve clinical outcomes. Each of England's ten NHS Ambulance trusts, as well as Wales, Northern Ireland and Scotland, all have at least one HART unit. This allows the team's capabilities to reach the whole of the UK (National Ambulance Resilience Unit (NARU), 2017). South Western Ambulance Service Foundation Trust (SWASFT) has two HART units—one based in Bristol and the other in Exeter.
It was deemed by SWASFT Special Operations that patient care could be improved, in both hazardous areas and regular pre-hospital clinical situations, by training and authorising HART operatives to autonomously administer ketamine up to 0.5 mg/kg for analgesia. The data available from the unit's ketamine usage were systematically audited and analysed with the aim of identifying current practice and developing recommendations for the future.
NHS departments require a comprehensive programme of quality improvement that should include the full participation of clinicians in clinical audit (National Institute for Health and Care Excellence (NICE), 2002). Embarking on this process enables clinicians to contribute to their organisation's clinical governance and thus promote a high quality of clinical care for patients (Benjamin, 2008).
Background
In the UK, ketamine is primarily used as an in-hospital anaesthetic agent; but when used in small doses, can be an effective and safe analgesic (Motov et al, 2015). Unlike morphine, ketamine maintains airway reflexes, respiratory drive and haemodynamic stability (Kurdi et al, 2014). Ketamine can be an effective substitute or adjunct to intravenous (IV) opioid pain medications and, in some instances, has shown superior efficacy (Hirota and Lambert, 2011; Duncan and Riley, 2016). Ketamine has long been identified as an appropriate analgesic for mass casualty situations and is frequently used by the United States (US) and UK armed forces in an array of austere environments (Kolawole, 2001; Svenson and Biedermann, 2011). This clearly demonstrates scope for inclusion of ketamine up to 0.5 mg/kg in the HART operational role to treat severe traumatic pain.
Training and education
HART paramedics from both SWASFT units received 2 days of classroom training from the Trust's Medical Director for Acute Care (MDAC). They subsequently carried out a written examination with an 80% pass mark based on the relevant Trust PGD (SWASFT, 2015), and scenario training, to demonstrate competency. Similar assessments are carried out on an annual basis to re-qualify personnel to continue to practise under the PGD. Under these conditions, 73 SWASFT HART paramedics were authorised from 4 July 2016 to administer ketamine, up to 0.5 mg/kg, for analgesia in the pre-hospital environment. Contact details for senior clinical advice ‘top cover’ were provided to all HART paramedics to support decision-making but not to authorise increased doses beyond the PGD. Top cover was provided 24 hours a day by one of four critical care doctors commissioned for the role from Great Western Air Ambulance Charity (GWAAC).
Methodology
Clinical audit is a process that seeks to improve patient outcomes through the systematic review of care against explicit standards and the implementation of change (NICE, 2002). With the aim of achieving this, HART paramedics were required to retrospectively self-report on a computerised auditing application called iAuditor on the details of ketamine administration after each use. The data attained were cross-referenced against controlled drug records to ensure all administrations were captured. To identify any complications or adverse events not detailed in the self-report system, any Datix® incident report forms relating to ketamine use that were completed during the audit period were also reviewed. All SWASFT HART paramedic ketamine administrations recorded between 4 July 2016 and 4 July 2017 were included in the review. Usage data were then collated using Microsoft Excel and analysed against the gold standard set out by the relevant trust PGD.
Findings and discussion
Sample and demographics
From a total of 759 incidents that SWASFT HART attended during the inclusion period, a sample size of 69 patients was achieved. In terms of gender, 58% (n=40) of patients attended were male, while 42% (n=29) were female. This is not surprising as trauma occurs predominantly in males (Collicott and Hughes, 1980). Kehoe et al (2015) found that in 2013, men accounted for 68% of all trauma cases in the UK; this was as a result of young males more often being involved in motor vehicle collisions and interpersonal violence.
The mean age for all patients was 49 years old (male: 43, female: 57) (Figure 1). When considering traditional opinions on trauma demographics, these ages are older than expected. Trauma has commonly been considered the leading cause of death and disability in the under-40 group (Krug et al, 2000) with the Trauma Audit and Research Network (TARN) (2017) revealing the mean age of trauma patients to be 36.1 years in 1990. These findings may be explained, however, by more recent statistics from 2013 (TARN, 2017) that suggest that the average age has now increased to 53.8 years.
The UK's ageing population means that elderly patients are making up an increasingly larger proportion of trauma incidents (Grossman et al, 2012). TARN (2017) reports that low falls are now the leading cause of trauma in elderly patients with Grossman et al (2012) adding that the likelihood of falls increases with age. The current audit found 32% (n=22) of patients to be 65 years of age or older.
Indications
Data were collected on the types of injuries for which HART paramedics were administrating ketamine (Figure 2). Unfortunately, in a small number of incidents, the administering clinician did not record the injury; these cases therefore form the ‘not stated’ category. A further omission was detail on incidents where ketamine was considered but not administered because of contraindications or complications. These data would have been useful to assess barriers experienced by HART paramedics during incidents. There should be scope for future audit or research to include this information.
The limb injury category displayed in Figure 2 is broken down into specific injury sub-categories inFigure 3, and is plotted against the patient age ranges that were encountered. Leg/hip injury makes up 63% (n=34/54) of the limb injury category. This sub-category includes any injury involving the long bones of the legs but excludes the ankle joint. This means that 49% of SWASFT HART's total ketamine administrations were for leg/hip injuries. The majority of these cases involved elderly patients.
A very small number of administrations involved cases where there was back, neck, pelvic, abdominal or chest trauma. There may be several reasons for this. Potentially, the presence of major trauma or serious injury in most cases leads to helicopter emergency medical service (HEMS) attendance and may result in HART not being required or, if on scene, not being involved in the pain management of the patient. It is also plausible that operational ambulance crews are requesting further analgesia or help with extrication for only simple and common fractures, but not for the trauma patient who is critically unwell.
To fully understand this, it would be useful to know in future whether HART are being requested for pain relief, or if the need for further analgesia is an incidental finding on scene when they were summoned for logistical support. Alternative explanations of the findings may be that the critically unwell patients encountered by HART are moved to hospital quickly in a ‘scoop and run’ fashion, or are so unwell that they have a lowered level of consciousness, which can contraindicate ketamine's use.
There may also be reluctance for paramedics to administer potent analgesic agents in incidents where injury is not obvious and the pain experienced by a patient is therefore poorly understood (Iqbal et al, 2012). Limb fractures, however, often present as a gross deformity; they may therefore provide more obvious and objective information and thus more readily promote the use of ketamine. Whatever the reason, more data are required to form a full picture of the situation, as the relatively small sample in the current audit may not provide generalisable data.
Administration and dosage
Mean ketamine dose calculations and administrations are displayed in Figure 4a and Figure 4b. Overall, HART paramedics reported that sufficient analgesia was achieved in 72% (n=50) of incidents where ketamine was administered (Table 1).
| Incidents where drug regime was carried out | Incidents where sufficient analgesia was achieved | Mean dose of Ketamine given to achieve sufficient analgesia | Mean percentage of maximum dose of Ketamine given to achieve analgesia | |
|---|---|---|---|---|
| Overall | N/A | 50 (72%) | 25 mg | 63% |
| Ketamine | 5 (7%) | 5 (100%) | 20 mg | 57% |
| Ketamine + Paracetamol | 6 (9%) | 5 (83%) | 31 mg | 70% |
| Ketamine + Morphine | 16 (23%) | 7 (44%) | 22 mg | 63% |
| Ketamine, Morphine + Paracetamol | 42 (63%) | 31 (74%) | 18 mg | 62% |
Although this appears to be a significant figure, it means that for every four patients encountered by HART, one did not have their analgesic needs met. This seems to be a poor rate of success for such a potent analgesic agent. In cases where analgesia wasn't sufficient, HART paramedics administered 82%, on average, of the maximum dose; this suggests that cautious use may be to blame. To investigate this further, analgesic drug regimes where ketamine was included were analysed.
The data suggest that ketamine used on its own, as well as a combination of paracetamol and ketamine, is more effective than any regime that involves morphine (Figure 5). Also, it appears that the addition of paracetamol to a morphine and ketamine regime dramatically improves that regime's efficacy. Both regimes involving morphine demonstrated the lowest efficacy.
Under the trust PGD (SWASFT, 2015), if morphine has been administered before, ketamine can only be given in 5 mg aliquots, which is half of the normal dose. This means that, in these cases, the normal dose of ketamine is administered at half the rate it normally is and may thus be proving ineffective. Continuing to administer 10 mg aliquots even when morphine has been administered could improve the effectiveness of the ketamine and morphine combination. Again, a larger sample size and a more reliable research methodology is needed before generalisations can be made. This may reveal data that are consistent with the current findings and promote a change in practice to a PGD with a higher ketamine dose.
Unfortunately, the success of the analgesia given was recorded by the clinician rather than the patient. This means that the HART paramedic's interpretation of whether a dose was sufficient was subjective, providing unreliable data. However, if a patient's pain score had been repeatedly recorded in all stages of analgesia administration, operator bias would have been reduced, making the data more reliable. Not including pain scores in the iAuditor template was a significant oversight of this project and has been fed back to the developers.
Clinical support
Access to top cover was provided to support HART paramedics' decision-making in relation to incidents where ketamine use was being considered. Although this service could provide advice, it could not provide verbal instruction to administer ketamine as this is prohibited for all Schedule 2 drugs under the Misuse of Drugs Regulations (The National Archives, 2001).
The audit review found that senior medical advice, or ‘top cover’, was sought in 23% (n=16) of cases (Figure 6). The author believes that this figure highlights HART's ability to operate autonomously in most cases, with only about one in four administrations requiring consultation. This number may decrease over time as experience and confidence grows. Of the 16 ‘top cover’ calls made, 100% were answered. This demonstrates reliable, consistent and easily accessible support and should serve as reassurance for HART paramedics in the future. Top cover call frequency did not reduce over the year so demonstrated no pattern of increasing confidence or autonomy.
The final aspect of clinical support was the requirement for HEMS to provide a higher dose of ketamine following administration by HART. This occurred in 9% (n=6) of cases. Of the incidents where a HART paramedic stated that the dose of ketamine was not sufficient to achieve appropriate analgesia (33%, n=2/6), HEMS were not present to provide further doses of ketamine. This means that only two of the patients enrolled had unmet analgesic needs caused by this situation.
Safety and complications
According to the iAuditor entries, no maximum dose of ketamine calculated by HART paramedics for a patient's weight was exceeded. It has been found, however, that the maximum dose has been calculated incorrectly in 13% (n=9) of incidents. Of these administrations, only 33% (n=3) exceeded the actual maximum dose for the patient weight reported under SWASFT (2015). Further investigation revealed that in all cases of miscalculation, patients exceeded 80 kg in weight. This suggests that, in some cases, the PGD is being misinterpreted for patients in the highest weight category. With regards to dose, the PGD guidelines appear in Figure 7.
It can be assumed that all miscalculated doses occurred because the HART paramedics involved were using the third point detailed in Figure 7 without considering the caveat of the fourth point, which supersedes it if the value calculated is less.’ Although most HART paramedics are calculating the maximum dose appropriately for this weight group (82%, n=40/49), this finding may represent confusion among some staff and thus a need for further clarification or simplification of the PGD's wording to prevent future occurrences. Three cases recorded on iAuditor stated complications of note and are detailed in Table 2.
| Complication post ketamine | Management | Outcome |
|---|---|---|
| Vomiting |
|
|
| Hypertension |
|
|
| Patient anxiety |
|
|
One incident involving ketamine administration was identified from the Datix incident reporting system. This was not identified by iAuditor report; this represents a further limitation of this method of data collection and indicates the potential for other incidences to have occurred that were not reported. This issue needs to be addressed for future audit.
The incident involved a patient with multiple fractures and significant pain management needs where attempts at IV and intraosseous (IO) access failed. The HART paramedic attending decided to administer ketamine intramuscularly (IM) which is outside of the scope of the PGD. Appropriate top cover could not be accessed on scene as a result of confusion over contact details, and the clinician subsequently aimed to act in the patient's best interests. As a result of the HART paramedic's actions, the patient experienced sufficient analgesia and was able to be moved from the scene comfortably. Although the care delivered was effective and within ketamine's license (Pfizer, 2018), the methods used fell outside of the local PGD. When practising under a PGD, health professionals are required to administer the medicine through the correct route (NICE, 2017). By not adhering to the conditions set out by the PGD, clinicians are in contravention of the Human Medicines Regulations (The National Archives, 2012). Ultimately, this incident resulted in no harm to the patient but was subsequently investigated via normal clinical governance channels. This resulted in the re-education of the HART paramedic and reiteration of the process for accessing clinical support to all HART staff.
Finally, there were no incidents reported on iAuditor where HART paramedics encountered a patient experiencing severe negative psychological symptoms after the administration of ketamine. This complication is often known as an emergence episode (Perumal et al, 2015). This is to be expected, however, as these side-effects are rarely encountered when using sub-anaesthetic doses (McGuiness et al, 2011).
Limitations
Self-report is a quick and inexpensive process that is potentially the only feasible method to collect data of this kind. The Trust's patient care records do not have scope to collect all of the data needed for the unit's ketamine audit and this is why a self-report methodology was chosen. The iAuditor template used, however, does require additional data fields to provide a more detailed clinical picture and thus produce more usable data. Despite its advantages, it provides very limited information on the incident and therefore makes it difficult to accurately analyse what happened. Furthermore, the methodology chosen by the developers for this project, means that the information gathered is subjective and open to bias with the potential for significant error.
This process was a clinical audit and not research. The World Health Organization (WHO) (2010) suggests that audit and feedback have only a small effect on improving professional practice. A clinical audit doesn't create best practice, it merely ascertains whether best practice is being followed (Smith, 1992). To identify true causal links between variables, robust research is required.
A recurring theme throughout the analysis is that a larger sample size is required to provide more data. Although this is an audit and not research with a high quality methodology, a larger sample size would inherently mean the findings would be more reliable and more representative of the population we encounter (Biau et al, 2008).
SWASFT is one of four HART units in the country that uses ketamine; accessing information on ketamine administration for all national units could potentially achieve more data. A standardised audit method could be adopted enabling detailed but homogenous data collection on a nationwide scale. Any required changes in practice could then be implemented on a much larger scale, improving care for a greater number of patients.
Conclusion
Despite the limitations of the current audit, this work provides potentially useful data. SWASFT HART demonstrated safe use of ketamine up to 0.5 mg/kg for analgesia with a high level of successful pain management. This adds to the evidence base demonstrating that paramedics are capable of administering ketamine autonomously. Some complications were recorded; however, the majority of these could have been encountered by even the most experienced clinician. Only one complication resulted from inexperience and it could be argued that this is to be expected during the bedding-in period of a new skill.
The Trust's ketamine for analgesia PGD requires improvement and simplification to prevent confusion. Ketamine dosage requires review by the appropriate facilitators as there is currently a number of patients who have unmet needs. The implementation of higher doses for analgesia also needs careful consideration.
Valuable learning points have been identified and proposed changes for practice now need to be discussed and agreed upon before any changes in practice can be made. Following this, a future audit needs to be carried out to assess the efficacy of these changes. There is potential scope for this to take the form of a national audit to achieve a greater and more generalisable sample. This must be done using a revised and more detailed audit template to extract as much information as possible from each incident.
This work has, at minimum, provided evidence that further clinical audit is both feasible and required. It has provided the foundations to further improve HART paramedic practice, while also adding to the evidence base for all trust paramedics to be able to administer ketamine. This may then pave the way for future, wider-reaching audit or high-quality research in this field.