Local anaesthetic (LA) agents are commonly used in all areas of healthcare, a fact that can be overlooked in maternity settings. The frequency of LA use in maternity care is significant, and includes epidural, spinal and pudendal nerve blocks, as well as subcutaneous infiltration before perineal tear repair. Care of patients using LA in maternity environments involves a particularly diverse multidisciplinary team, with a broad range of training backgrounds: midwives, maternity support workers (MSWs), anaesthetists (obstetric and general), obstetricians, junior doctors, and operating department practitioners, as well as midwifery and medical students, who may be involved in the care of a single woman to whom LA has been administered. It is therefore crucial that these agents and the risks associated with them are well understood by all groups.
Although LA is relatively safe (Skidmore et al, 1996), there are risks associated with its use, the most serious of which is local anaesthetic systemic toxicity (LAST). This is reported in up to 1 in 1000 peripheral blocks (van der Nest, 2012) and has resulted in maternal mortality and morbidity in the UK in recent years, although incidence is understood to be underestimated due to poor knowledge and recognition of LAST, and subsequent under-reporting (Collins, 2010). LAST represents a particular risk in the maternity setting, given the frequency of LA usage and the wide range of health professionals (and thus educational backgrounds) involved in patient care.
LAST awareness has been investigated and reported by a number of studies from across the globe and in various clinical settings (Jensen-Gadegaard et al, 2011; Walsh et al, 2012; Sagir and Goyal, 2015; Karasu et al, 2016). To date, however, this has largely been focused on doctors and emergency care settings, and has not extended to the higher-risk environment of maternity care. In fact, the epidural knowledge of maternity and midwifery staff has been identified as a particular concern in the past (Davies et al, 1993; Vandendriesen et al, 1998; Bird et al, 2009), but LAST has been seemingly overlooked even when LA knowledge was assessed.
This study aimed to investigate knowledge of LAST across all staff disciplines working at a maternity unity at Queen Elizabeth the Queen Mother Hospital, Margate, which is part of East Kent Hospitals University NHS Foundation Trust. The aim was to identify particular areas for future improvement through interprofessional educational intervention.
Methods
Participants
The survey was carried out in a district general hospital maternity unit and involved members of staff working in both midwifery-led and consultant-led areas. Staff in this clinical area consisted of MSWs, midwifery students, midwives, junior doctors, consultants in obstetrics and gynaecology and anaesthesia, and theatre staff. Due to high staff turnover, a result of both shift work and the presence of permanent and non-permanent (bank, locum or agency) employees, it was not possible to quantify the total population in this study. Ethics approval was not required, as service-users were not directly involved.
Survey
A brief questionnaire was adapted from a previous audit at another site in the hospital Trust. This comprised questions in four broad domains: LA safe maximum doses, recognition of LAST, immediate management of LAST and the use of lipid emulsion in reversal of LAST. Additional questions were included in the lipid emulsion domain in order to determine site-specific knowledge (location of this product in the unit). Maximum doses of common LA agents were determined according to advice from consultant anaesthetists elsewhere in the Trust. All questions had free-text answers and multiple choices were not provided.
Participants were also asked to indicate whether or not they used LA in their own practice or worked in an area in which LA was routinely used; if they were aware of guidelines relating to LAST; and whether or not they had knowingly encountered a case of LAST in the past. Attempts were made to anonymise responses: participant names were not collected and researchers were not present on the unit during the sampling period; however, clinical role and band/level were included in the survey, meaning that complete anonymity was not possible.
Surveys were printed and distributed throughout the maternity unit by the researchers on a single day, and a sealed box was provided for completed surveys. A 24-hour period was allocated for responses, in order to provide a representative sample. Data were then entered into Microsoft Excel manually and analysed.
Results
Participants
A total of 23 members of staff responded to the survey, representing all staff groups: doctors (17%), midwives (65%), midwifery students (9%) and MSWs (9%) (Figure 1). Two doctor respondents were consultants, both anaesthetists, and two were trainees in obstetrics and gynaecology. Midwife respondents were from Bands 5–8, with distribution shown in Figure 2. Overall, 83% of respondents reported that they used LA in their work; however, of those who did not, all reported working with LA or being responsible for patients to whom it had been administered. Only 17% were aware of any guidelines relating to LAST (13% midwives, 50% doctors: 100% consultant anaesthetists, 0% obstetrics and gynaecology trainees).
Overall performance
A scoring system was devised to enable crude comparison of overall performance between staff groups. Figure 3 shows average total scores according to clinical role as determined by this system. Average score across all respondents was 3.9. Consultant anaesthetists performed better than all other staff groups (mean=11); midwives scored 3.7, student midwives 2.5, junior doctors 2, and MSWs 1.
Figure 4 demonstrates the proportion of correct responses according to question domain. Knowledge of LAST signs and symptoms was particularly poor (8.7% correct responses); however, proportions were below 25% in all domains, with 17.4% of responses correct on safe maximum doses, 21.7% correct on questions of immediate management and 24.6% on questions related to the use of lipid emulsion.
Safe maximum doses
Respondents were asked for the maximum safe doses (mg/kg) of 5 common LA preparations: lignocaine (3 mg/kg), lignocaine with adrenaline 1:200 000 (7 mg/kg), bupivacaine (2 mg/kg), levobupivacaine (2-3 mg/kg) and ropivacaine (3-4 mg/kg). No member of staff provided accurate responses to all 5 questions; the two consultant anaesthetists responded with 60% and 80% accuracy.
In total, 57% responses regarding lignocaine were correct, with doctors scoring lowest (0% correct) and MSWs highest (100%). Overall, 50% of midwifery students and 67% of midwives provided correct answers. The correct maximum safe dose of lignocaine with adrenaline was provided by 4% of the total respondents, and 25% of doctors. Maximum safe doses of bupivacaine, levobupivacaine and ropivacaine were only provided by consultant anaesthetists (50% doctor respondents; 9% total respondents).
Recognising LAST
Respondents were asked to provide at least 3 clinical features of LAST. Acceptable answers were:
Knowledge of LAST signs and symptoms was poor across all disciplines and grades. Overall, 9% could identify 3 clinical features (50% doctors only), and only 48% could identify at least one feature (75% doctors; 47% midwives; 50% midwifery students; 0% MSWs).
Immediate management of LAST
Respondents were asked to list at least 3 actions that they would carry out in the immediate management of LAST. Acceptable answers were defined according to the Association of Anaesthetists of Great Britain and Ireland (AAGBI) guidance on immediate LAST management (AAGBI, 2010), which included:
All indicated that they had not knowingly encountered a case of LAST in the past.
Only 22% of respondents provided 3 correct answers (25% doctors, 27% midwives). Although 83% (75% doctors, 93% midwives, 100% midwifery students, 0% MSWs) were able to identify at least one of these immediate management steps, only 70% indicated that they would call for help in this scenario. Some 35% answered that they would stop LA administration, and only 17% indicated knowledge of lipid emulsion (in that they would locate or administer it).
Use of lipid emulsion
When asked directly to identify an appropriate antidote for LAST, 30% responded correctly (75% doctors, 27% midwives). In total, 39% correctly provided the route of administration of this antidote (50% doctors, 40% midwives, 50% midwifery students, 0% MSWs). Only one respondent (a Band 8 midwife/midwifery matron) correctly identified the location of the lipid emulsion antidote in their clinical area.
Discussion
All participants in this survey recognised that they worked with LA either directly or indirectly; however, awareness of guidelines and of LAST itself was poor across all staff groups and grades. This could in part reflect confusion as to what exactly constitutes LA. Further support for this idea came from informal conversations with various members of maternity unit staff after the data collection period. It transpired that many did not perceive epidural and spinal blocks as LA use in the same way that they did more superficial LA injections that were used in perineal repairs. It is now clear that assumptions were made in devising the survey, which could be easily modified in order to qualify and quantify the extent of such confusion.
The finding also suggested that guidelines may not have been accessible to staff. In similar post-survey conversation, it was reported that the AAGBI guidelines linked on the Trust intranet pages were perceived to be for specialist use and therefore overlooked by non-anaesthetists. This has highlighted a problem in communicating specialist recommendations to all members of a multidisciplinary team to whom they are relevant.
Overall survey performance was poor across all groups except consultant anaesthetists. This serves to highlight LA and LAST as an area of unmet educational need for all disciplines, corroborated by informal reports that LAST is not universally included in medical or midwifery undergraduate curricula or local postgraduate training. It is also worrying that, despite relatively high scores, specialists were not entirely accurate in their responses—particularly those relating to maximum safe doses of common LA agents. This may suggest that LAST education during specialist training is not sufficient and that regular revision is required to maintain an acceptable level of knowledge. On a local scale, LA and LAST could be included in induction teaching and annual mandatory and statutory training for all staff members with responsibility over patients using LA.
However, consideration must be given to the level of knowledge that is appropriate for different clinical roles. It became apparent, upon in-depth interrogation of our data and from post-survey verbal reports, that some of the examined knowledge was not relevant to all groups. For example, knowledge of maximum safe doses of LA agents other than lignocaine may not be required of midwifery staff due to non-routine use. The survey or the method of scoring could be modified in this way for future application.
Although this is not the first examination of LAST knowledge in a multidisciplinary setting, there is a paucity of such information in the context of maternity care. Concerns about poor knowledge of LA and LAST among non-specialist medical professionals and non-medical professional groups have previously been raised (Vandendriesen et al, 1998; Jensen-Gadegaard et al, 2011; Sagir and Goyal, 2015; Karasu et al, 2016) and both the frequency of LA use (Jenkins et al, 2003; Jadon, 2010; Lai et al, 2014) and the additional risks in maternity service-users are well-understood. These factors, as well as a number of high-profile incidents (Morgan, 1995; Morris, 2008; Neuhaus et al, 2016), make this clinical area one of particular concern.
The greatest concern identified in this study was that recognition of LAST was the domain of poorest performance. Recognising events is obviously a requirement for any immediate management and antidote therapy, and must be targeted as priority in educational intervention. It is relevant to all staff groups as all share responsibility for patients using LA and identified themselves as such. Upon examining free-text answers in this domain, widespread confusion of LAST with either an adverse drug reaction or with anaphylaxis was identified. This could have serious implications in the event of LAST, as the conditions have distinct management pathways. Further confusion was identified in the lipid emulsion domain, with some staff members suggesting naloxone or promethazine as the antidote in LAST. This lends further support to the inadequate coverage of LAST in medical and midwifery curricula, and it is therefore important at undergraduate level and above, as the widespread use of LA in healthcare make it relevant in all areas of patient care.
A final area of concern was in identifying the location of lipid emulsion on the maternity unit, to which only one participant (the maternity matron) responded correctly. Immediate action has been suggested at the site so that all staff members know the location of and have access to lipid emulsion.
Limitations
While this study adds to a growing body of literature concerning LAST awareness, and provides a crucial insight into problems particular to maternity care, there were a number of limitations. Firstly, the sample size was small and while efforts were made to take a representative sample, the authors were not able to confirm this by characterising the population. However, similar deficits have been identified in knowledge examining the issue in other areas of healthcare, particularly relating to specialist and non-specialist knowledge discrepancies (Karasu et al, 2016). Additionally, whether or not they are an accurate representation on a wider local or even national scale, these findings represent a real risk to patient safety: adverse events can occur on account of individual actions (Morris, 2008). Given the utility of data from this small pilot investigation, the authors would like to disseminate this survey more widely to generate more robust data.
In a similar vein, the data collection period was short. This was in part to try to provide proportional representation of staff groups working in this unit, but will have contributed to the small sample size.
There are also ways in which the survey itself could be improved for future use, which have been discussed above. In summary, questions could be included on awareness of what constitutes LA in maternity care, previous LAST education, attitudes towards guidelines and attitudes towards patient responsibility. Some insight into these areas was gained through informal verbal reports after the data collection period, although qualifying this would improve reliability. The scoring method could also be amended to take into account the levels of knowledge appropriate for different clinical roles.
Conclusion
These findings highlight the need for LAST to be included in education at all levels, from undergraduate curricula to postgraduate non-specialist training in medical and midwifery pathways. It would also be pertinent for LAST to be a mandatory and statutory training requirement for maternity unit staff. There is support in the literature for the use of simulation training, such as moulage, in improving cross-disciplinary education in maternity care (Crofts et al, 2007), which may be easily applied to LAST.
Several recommendations have also been made at a local level following this study, including that the location of lipid emulsion must be made clear and accessible to all staff, not just to specialists, and that guidelines be publicised. Information should also be made available in the unit for reference, so as to improve knowledge more immediately and to minimise the risk of maternity morbidity and mortality in the event of LAST. This could take the form of information sheets, departmental posters or personal reference aids. Further data could be collected to assess the impact of educational tools after their implementation.