A Bit Early and A Bit Far Away

We welcome another new contributor to the site with this post. Jodie Martin is a clinical educator and flight nurse working in the Top End of Australia. She has just finished up a Masters which included looking at a big retrieval challenge – preterm births in the wild reaches of the Northern Territory. 

Which retrieval taskings scare you the most? Is it the paediatric trauma patient in the prehospital setting, a long way away from the nearest trauma setting? Or perhaps the critically unwell and septic neonate in a remote clinic, which you know will take you 6 hours to retrieve to a hospital?

For me, it’s the women in preterm labour. Even after 10 years of flight nursing, it’s the women in preterm labour that make me nervous.  And before I became a flight nurse I’d been a midwife for several years, working in rural and remote settings where I became fairly comfortable caring for obstetric patients in an isolated setting, because you had to be really. Aeromedical retrieval teams are rarely as quick as you’d like out there.

So even after a lot of exposure to obstetric patients in isolated areas, it is the preterm labour cases which make me sit on the edge of my seat. These are the cases I really want that crystal ball so we can foresee what is going to happen; is this woman going to deliver before we get there? Do we need to spend time on the ground to wait for birth or can we risk it and transfer her in labour and get her to hospital in time to allow preterm birth in a tertiary health centre? How will I manage an unexpected birth of a preterm baby during flight? Do I need to take all of the 100kg+ neonatal equipment to care for a preterm neonate? Do we need a paediatrician, just in case?

A Brief History of Stopping Labour in the Top End

In 2009 or there about, obstetric services in the Top End of the NT moved away from using IV salbutamol and started using nifedipine as the tocolytic of choice.  This was because nifedipine was seen as a safer tocolytic with less adverse maternal side effects. In particular, there is a high incidence of rheumatic heart disease in the NT and we now had a better option of avoiding the negative effects IV salbutamol can have on cardiac function.

We already knew that facilitating in utero transfer of preterm babies improves their outcomes so that was still our aim. 1 However, I was yet to be convinced nifedipine was a superior choice for the aeromedical transfer of women in preterm labour.

So we turned to the literature to find out about the incidence of inflight births and to determine what happens to the women in preterm labour transported by aeromedical retrieval. Some studies reported no births occur in flight.2 However these studies utilise different types of tocolytics than our aeromedical retrieval service. A Canadian aeromedical retrieval service did report inflight births. 4 of these births occurred despite tocolysis but that tocolytic was not a calcium channel blocker such as nifedipine and the other births received no tocolysis at all 3. Anecdotally we knew at CareFlight NT we’d had 3 inflight preterm births despite nifedipine being administered. In three different Australian based studies which reviewed the transfer of rural and remote women, approximately 50% are in fact discharged.2,4,5

So what about the risks for pregnant women in the Northern Territory? Unfortunately, the news is not good. The NT has the highest rate of preterm births in Australia with 10% of all births occurring before arrival to hospital.6 Indigenous women and newborns do worst on some birth outcomes if they live in a remote area of the Top End of the NT7 and the NT has the highest maternal death rate in Australia.8 So being an Indigenous pregnant woman in a rural remote area of the NT is a combination of a lot of significant risk factors.

Let Me Paint You a Picture of Where We Work

The Top End is a geographical area twice the size of the UK & a just a little smaller than Texas, so around 400,000km2. There are two small rural hospitals which undertake planned low risk, term births. Both hospitals have emergency obstetric and caesarean capability along with the ability to provide immediate neonatal emergency care, but have limited resources to care for a preterm newborn for any extensive period of time.

There are over 35 small remote health centres we service. These health centres have no inpatient facilities and do not perform planned births. These centres can sometimes manage an unexpected normal birth but have no theatre or neonatal nursery care resources. Sometimes there is a remote area midwife available.

There’s only one NICU, which is located at Royal Darwin Hospital. The next closest NICU is 3,027km away in Adelaide. So when a woman presents in preterm labour in a rural or remote area in the Top End of the NT there is a natural level of anxiety as resources are limited, retrieval times can be long and we know we have a high risk obstetric population.

So I thought it was worth looking at our own data on the women we transport in preterm labour to find out more about their outcomes. Plus I needed to do a research project to complete a Masters’ degree.

The aim of our 3 year retrospective study was to determine the outcomes of women in preterm labour transported by aeromedical retrieval. We reviewed all the cases of preterm labour referred to CareFlight NT. Preterm labour was defined as 23+6 to 36+6 weeks gestation with a viable pregnancy. We excluded those women who had been referred after a preterm birth had already occurred. After exclusions for missing & incomplete data, we ended up with a sample of 304 women referred in preterm labour. We examined discharge data at Royal Darwin Hospital to review the outcomes.

What we found

Demographics and retrieval times
The average gestation was 32+2 week and 90% of the women we transferred were Indigenous (there’s that high risk obstetric factor again I mentioned previously).

Retrieval time was taken from time of referral to our logistics coordination unit (LCU) to time of handover at the receiving hospital. Average retrieval time was 5.55hrs. Those women who proceeded to a preterm birth had an average time of birth following referral as 5hrs. Therefore there will be times when a preterm birth occurs before we can get to our destination.

Where preterm birth occurred
The places where women did give birth to a preterm baby:

16% in a remote health clinic

7% in a rural hospital

73% in RDH – the only tertiary health centre in the Top End with neonatal intensive care capabilities

4% elsewhere -3 births occurred in flight, 1 on the tarmac of a remote airstrip and 1 interstate.

Preterm birth remote airstrip-2
Yes of course, this is exactly where we’d like to be setting up for a preterm delivery.

Nearly half of all preterm births which occurred in a rural hospital had been transferred from a remote community to a rural hospital instead of the tertiary centre. It is thought the rural hospital may have been chosen as a destination on occasions it was closer than Royal Darwin Hospital from the referral site and the long transfer was thought likely to end with an inflight birth. This reflects the decision making clinical crews have to be able to make on the run. Detailed midwifery and obstetric assessments and sound judgement are vital skills that the teams have to deploy when faced with the aeromedical retrieval of pregnant women in preterm labour.

Who went on the flights
79% of all retrievals in this cohort were conducted by a flight nurse/midwife alone; 15 (or 44%) of all preterm births occurred outside of any hospital (being a rural or tertiary hospital) with a flight nurse/midwife only crew. This certainly highlights the importance and requirements for ongoing education and training in midwifery, obstetric emergencies and neonatal resuscitation for our flight nurse/midwives plus our rural and remote health colleagues.

Neonatal resus eduation and training-2
Slightly less pressure here.

14% (n=42) of all preterm labour referrals included a CareFlight flight doctor + flight nurse/midwife mix, with 12 preterm births occurring prior to arrival to a tertiary health centre. A paediatrician/paediatric registrar went on 23 taskings (7%) and their skills were required in 5 cases where a preterm birth occurred whilst another 6 of these cases with a paediatrician/paediatric registrar resulted in the woman being discharged with no preterm birth occurring.

Tocolysis
What about the transfer of women in labour after they’d had nifedipine? About half of the women were still contracting upon handover at the receiving hospital whilst 42% had stopped contracting upon handover. 13% of referrals of women in preterm labour delivered a preterm baby prior to arrival at a tertiary health centre despite tocolysis, which could reflect women presenting late in labour & nifedipine not being useful in these and other instances.

Birth outcomes
In aiming to facilitate preterm birth in a tertiary hospital, there will always be a proportion of women who are subsequently transferred and do not go onto give preterm birth. We had a discharge rate of 49% where no preterm birth occurred. Our findings are comparable to other Australian studies. One previous study reported 53% of women in Western Australia transferred by aeromedical retrieval were discharged without birth occurring2 and another study reported 46% of women from rural areas in New South Wales were discharged following transfer to a tertiary centre.5

Yet another study reported 42% of women were discharged without birth occurring following transfer and the authors suggested that remoteness was associated with increasing rates of antenatal transfer.4  This is evident in the results of our study as we found 4% of women were transferred two or more times during a current pregnancy, reflecting the remote nature of the area we service and the high risk obstetric population. We need to expect that in the interest of maximising outcomes for mothers and babies from rural and remote areas, facilitating preterm birth in a tertiary hospital will result in some unnecessary yet costly aeromedical retrievals.

Triage and priority coding

The majority of women were triaged and retrieved appropriately to facilitate aeromedical retrieval in a timely fashion to enable a preterm birth in a tertiary hospital (73%). Five out of the 11 preterm births in a rural hospital were initially planned for retrieval from a remote health centre to the tertiary hospital but were transferred to a rural hospital instead. This may have occurred as the aeromedical crew found the woman was in more advanced labour than anticipated and elected to choose the closer rural hospital. Other aviation factors such as adverse weather may also play a role in these decisions.

Thus triage and priority coding for women in preterm labour reflects accuracy in the need for prompt retrieval, but also sometimes later decisions by the retrieval team who are required to make judgements upon arrival as to whether to allow birth to proceed in an environment with limited resources or risk inflight birth. Decision making on triage and priority coding will always revolve around the facilities and skill of personnel at the referring site, distance, gestational age, cervical dilation, labour advancement and maternal and fetal risk factors.

Stuff this bit of research didn’t tell us

There were several limitations in our study, namely the small sample size and lack of stratification of obstetric risk factors. It was intended at the commencement of this study to report on the doses of nifedipine administered. However, due to lack of documentation and ability to clarify the doses administered, it was decided early in the data collection process to discontinue recording the doses. Thus it has been assumed the dose administered is in accordance with local clinical guidelines (oral nifedipine 20mg given 20-minutely to a maximum of 3 doses in 1 hour then 20mg 3 hourly)10. The doses of nifedipine actually administered may be different to that recommended and therefore the success of in-utero transfer may be dependent on the dose of nifedipine administered.

The Bit for the Fridge Magnet

So, the take home points when it comes to the aeromedical retrieval of women in preterm labour:

  • Prompt retrieval of women in preterm labour is vital to facilitate preterm birth in a tertiary health centre with neonatal intensive care facilities to improve neonatal outcomes or at least get the neonatal intensive care unit to the neonate in a timely manner;
  • Early and aggressive management of preterm labour with nifedipine improves the success of an in-utero transfer;
  • We have a high risk obstetric population in the NT – remember the importance of other preterm labour clinical guidelines such as the administration of steroids and IV antibiotics;
  • Send the right team at the right time. One member of the aeromedical retrieval should have an obstetric/midwifery background. It’s the detailed obstetric assessment which will assist a crew to make that decision of whether to stay and play or scoop and run, hopefully avoiding inflight birth and facilitating a successful inutero transfer to a hospital;
  • Ongoing regular education and training in neonatal resuscitation, neonatal care and obstetric emergencies is paramount for our flight nurses and flight doctors;
  • In the interests of improving maternal and neonatal outcomes, we have to accept that there will be some retrievals of women in preterm labour which weren’t required as a half of them will end up being discharged;
  • Flight crews and retrieval consultants make some tough decisions when it comes to the aeromedical retrieval of women in preterm labour…if only we could have that crystal ball. But at least we know we’re making the right decisions regarding flight crew mix, triage and whether to put a woman in preterm labour on an aircraft or wait on the ground for birth to occur.

And for more details I’ll just have to let you know when the publication hits the journals (very soon I hope …)

 

Notes:

The staff in those photos are OK with those being shared.

The image of MKT airstrip is a Creative Commons one from flickr and is unchanged from the original Ken Hodge posting.

References:

  1. Tara P, Thornton S. Current medical therapy in the prevention and treatment of preterm labour. Seminars in Fetal and Neonatal Medicine. 2004;9(6):481-489. doi:10.1016/j.siny.2004.08.005
  2. Akl N, Coghlan E, Nathan EA, Langford SA, Newnham J. Aeromedical transfer of women at risk of preterm delivery in remote and rural Western Australia: Why are there no births in flight? Australian and New Zealand Journal of Obstetrics and Gynaecology. 2012;52(4):327-333. doi: 10.1111/j.1479-828X.2012.01426.x
  3. McCubbin K, Moore S, MacDonald R, Vaillancourt C. Medical transfer of patients in preterm labour: Treatments and tocolytics. Prehospital Emergency Care. 2015;19(1):103-109. doi:10.3109/10903127.2014.942475
  4. Hutchinson F, Davies M. Time-to-delivery after maternal transfer to a tertiary perinatal centre. Biomed Res Int. January 2014:1-6. doi: 10.1155/2014/325919
  5. Badgery-Parker T, Ford J, Jenkins M, G. Morris J, Roberts C. Patterns and outcomes of preterm hospital admissions during pregnancy in NSW, 2001-2008. Med J Aust. 2012; 196(4):261-265.
  6. Barclay L, Kruske S, Bar-Zeev S, Steenkamp M, Josif C, Narjic C, Kildea S. Improving Aboriginal maternal and infant health services in the ‘Top End’ of Australia; synthesis of the findings of a health services research program aimed at engaging stakeholders, developing research capacity and embedding change. BMC Health Services Research. 2014; 14(1):241.
  7. Steenkamp M, Rumbold A, Barclay L, Kildea S. A population-based investigation into inequalities amongst Indigenous mothers and newborns by place of residence in the Northern territory, Australia. BMC Pregnancy and Childbirth. 2012;12(44): doi:10.1186/1471-2393-12-44. http://www.biomedcentral.com/1471-2393/12/44. Accessed August 13, 2015.
  8. Li Z, Zeki R, Hilder L, Sullivan E. Australia’s mothers and babies 2011 Perinatal statistics series no. 28. 2013. http://www.aihw.gov.au/publication-detail/?id=60129545702. Accessed August 10, 2015.
  9. Roberts C, Henderson-Smart D, Ellwood D. Antenatal transfer of rural women to perinatal centres. High Risk Obstetric and Perinatal Advisory Working Group. Aust N Z J Obstet Gynaecol. 2000;40(4):377-384.
  10. Alukura C. Minymaku Kutju Tjukurpa – Women’s Business Manual (6th Ed). Alice Springs: Centre for Remote Health; 2015

The Elephant in the Room: Airway Stuff for Non-Intubators

Tim Wallace, emergency nurse, midwife and flight nurse from the Top End, returns to the blog with a different look at a popular topic – airway management. 

Some stuff to ponder for the non-intubators…

 Do you routinely assess, plan and prepare for airway issues in patients with a risk of airway compromise?

Could you honestly say you would be able to reliably manage A and B on your own?

Who does the work?

Emergency airway and ventilation management is routinely performed by a group of providers that it would be reasonable to call airway non-experts. This group includes paramedics, nurses, lifeguards and community first responders. Amongst these individuals there is significant variability in initial & ongoing training, experience and exposures to relevant simulated and actual airway/ventilation management.

A 2011 audit using data from 16 US states (Wang et al table 1) reveals 23% of interventions that could be classified as ‘critical care’ level, and while it is impossible to determine the skill level of the providers who performed the other 77%, it is reasonable to assume that they were not all critical care clinicians.

Conversely, the narrative and evidence base is dominated by the group who probably perform the lowest volume of work (the intubators). While I’m not arguing that we’ve heard the final word on interventions like pre-hospital RSI, I figured it was time to talk about the non-intubators, which for the purposes of this discussion I’m going to limit to paramedics and nurses – not necessarily novices and not necessarily inexperienced.

Whilst I have ignored endotracheal intubation (ETI) and those trained to do it as any casual observer will recognise the internet is bursting at the seams with content on advanced airway management. At times I get the impression from the blog/social media world that intubation (with ketamine) is some kind of panacea. If we glance over at the situation for our “occasional intubator” (typically medical or paramedic) who performs between 1 and 50 people per year (Reeves & Skinner 2008), there is  acknowledgment of and significant controversy in the state of affairs around procedural success and risk.

I think it’s reasonable that we apply the same scrutiny to the non-intubators.

Really Simple Things

Simple airway management and bag-valve-mask (BVM) ventilation are simple yeah?

I’ll try to avoid the term ‘basic airway management’ because I don’t really think it’s very basic; positioning, manoeuvres, suction, BVM, oral and nasal airways etc. I’ll also chuck in intermediate-advanced airways like LMAs (laryngeal mask airways) as we are generally all trained and expected to use them if required. 

Despite how these skills are represented in many courses and the common fallacy within the health system that completion of an Advanced Life Support course confers reliable competence in advanced life support (alluded to by Kidner and Laurence, 2006), it turns out in the hands of the less skilled/experienced operator, it can be very difficult to achieve airway control and maintain ventilation. Anaesthetists don’t really represent basic airway management as basic, so the rest of us probably shouldn’t either.

The Literature and BVM

Unsurprisingly, Walsh et al (2000) demonstrated anaesthetists were better at BVM ventilation than other doctors, supporting the notion that training, experience and exposures matter when it comes to this skillset. The evidence-based consensus (e.g. Otten et al, 2014) is that 2 handed (versus 1 handed C-grip) BVM technique is superior. However, while 2-person BVM (outside the OT) should be the stated aim, this is not an option on a nurse-only retrieval or in the back of a moving ambulance. Interestingly, in this experiment subjects with more experience bagging people in emergencies did not perform better than inexperienced subjects, though you would imagine this might change if you introduced a toothless bearded man with down syndrome into the mix.

In Noordergraaf et al’s useful 2004 study on real (anaesthetised) people, fire-fighters with 3 hours training on airway/ventilation management attempted to maintain airway patency and deliver BVM ventilation. Up to 23% of the time, they could not maintain an airway using BVM, simple manoeuvres and adjuncts. Additionally, half the time the patients received ineffective ventilation.

In 2011, Adelborg et al evaluated professional life-guard resuscitation performance, comparing mouth to mouth/pocket mask and BVM ventilation. Noting that amongst some lifeguards it was “common sense that BVM [was] superior” (despite the fact that it wasn’t a mandatory part of lifeguard training), their results demonstrate that this is probably a flawed assumption.

Finally, the Finns revealed ‘basic airway management’ for what it is, amongst a cohort of new/clinically inexperienced paramedics, who were allocated a cardiac arrest scenario utilising either BVM, LMA or ETI management after initial training – the group that achieved the poorest ventilation (and by inference airway control) were in the BVM arm! (Kurola et al 2004).

That’s OK, these days we don’t even bother with BVM …

The literature generally suggests LMA devices (v BVM) are easier to learn to use and are superior for airway control / ventilation with a number of people pretty much advocating canning the BVM and going straight for a LMA. Rechner et al (2007) showed that Critical Care Nurses with one hour of training on LMA insertion were able to maintain airway control and ventilate children 82% of the time using LMAs compared to 70% using BVM/adjuncts. Further, utilising LMAs (as opposed to BVM) in initial airway management of cardiac arrests appears to protect arrestees from gastric aspiration (Stone, Chantler, Baskett 1998).

However, while LMAs are undoubtedly the shizz and minimally experienced providers can generally insert them easily enough while supervised in the OT or during manikin simulation, success with this device does not appear to reliably carry over to the real life setting e.g. Hein et al 2008 with 65% success within 2 attempts during out of hospital cardiac arrest.

Now here’s a few useful acronyms I first came across at Life in the Fast Lane:

Difficult BVM = BONES

  • Beard
  • Obese
  • No teeth
  • Elderly
  • Sleep Apnea / Snoring

Difficult LMA = RODS

  • Restricted mouth opening
  • Obstruction
  • Distorted airway
  • Stiff lungs or c-spine

I was at a recent conference ‘show and tell’ type talk from a representative of a very high-performance paramedic based EMS system. Amongst other things, he talked about the level of audit and scrutiny applied to pre-hospital RSI performed by his service. At the end I asked if they audited the airway interventions/management of their non-RSI accredited providers (no). Realistically this group of providers will still be called upon to manage A and B, and when they do it’s likely to be because there is no backup available – I’m picturing a patient in some kind of extremis. Due to the clinical characteristics of this patient group (cardiac arrest, neurological emergencies, respiratory decompensation etc.), I’d imagine that if there was a negative outcome, it may be difficult to trace it back to a failure of some basic intervention in the kind of way you could if they were performing intubation +/- RSI.

In an methodologically dodgy study conducted by me (2016), non-physician providers (n=I can’t remember), were asked “if you were by yourself and had to bag someone, would you be confident that you could do it successfully?” The responses were generally polarised reflecting unflinching confidence in their abilities or cautionary pessimism that they would give it their best shot but were not optimistic – one told me “if they were honest with themselves most people would

”. This observation appears to mirror the findings of Kidner and Laurence (2006), who evaluated the basic airway and ventilation competence of junior doctors (n=20) on anaesthetized theatre patients. While pre assessment 85% said they were confident in their ability, only 40% demonstrated initial competence to the minimum standard.

Mr Tusko copy
I’d imagine some of my colleagues with smaller hands might be concerned about getting a good seal on Mr Tusko.

 

Where do you work?

There is a certain irony in our office at work. Over the way in aviation, our pilots are becoming more skilled and experienced almost every shift undertaking high risk, single pilot operations day and night. Yet they still have high volume training and re-currency requirements. Arguably, if they crash the plane we’re all screwed, but I’m not the first person to articulate the idea that we medical people have some lessons to learn from aviation. Raatiniemi et al (2013) have some suggestions about how to rectify the current state of affairs (from a setting that has practical similarities with EMS operations in rural and remote Oz):

– targeted airway management courses (not that such a thing actually exists!)

– simulation and manikin training

– supervised hands on time in OT (probably the gold standard)

– registering / auditing procedures to target training and supervision.

Care to Read More?

Here’s a good blog post on two v one person BVM and some other BVM stuff.

Flavel and Boyle’s excellent 2010 LMA vs BMV is worth a read (the full reference is below).

Additionally, Dr Aaron Conway’s research project “Survey to improve the quality of the training and education that nurses receive about conscious sedation” is worth pondering for the non-airway experts and I imagine the results of this study will provide an important contribution to this discussion. Check it out in detail here

Now the bibliography:

Adelborg, K., Dalgas,C.,  Lerkevang Grove, E., Jørgensen, C.,Husain Al-Mashhadi, R., Løfgren, B. (2011) Mouth-to-mouth ventilation is superior to mouth-to-pocket mask and bag-valve-mask ventilation during lifeguard CPR: A randomized study. Resuscitation 82, 618–622.

Flavel, E, Boyle, M. (2010) Which is more effective for ventilation in the prehospital setting during cardiopulmonary resuscitation, the laryngeal mask airway or the bag-valve-mask? – A review of the literature. Journal of Emergency Primary Health Care. 8(3)

Hein C, Owen H, Plummer J. (2008) A 12-month audit of laryngeal mask airway (LM) use in a South Australian ambulance service. Resuscitation;79:219–24.

 Kidner ,K. Laurence, A. (2006) Basic airway management by junior doctors: assessment and training on human apnoeic subjects in the anaesthetic room. Anaesthesia, 2006, 61, pages 739–742

Kurola, J. Harve, H. Kettunen, T., Laakso J.-P. Gorski, J. Paakkonen,H. Silfvast, T. (2004) Airway management in cardiac arrest—comparison of the laryngeal tube, tracheal intubation and bag-valve mask ventilation in emergency medical training Resuscitation 61 149–153

Noordergraaf, G, van Dun, PJ, Kramer, BP, Schors, MP, Hornman, HP, de Jong, W, Noordergraaf, A. (2004) Airway management by first responders when using a bag-valve device and two oxygen-driven resuscitators in 104 patients. European Journal of Anaesthesiology, 21(5)

Otten, D, Liao, M, Wolken, R, Douglas, I, Mishra, R, Kao, A, Barrett, W, Drasler, E, Byyny, R, Haukoos, J (2014) Comparison of Bag-Valve-Mask Hand-Sealing Techniques in a Simulated Model. Annals of Emergency Medicine, 63(1)

Raatiniemi L1, Länkimäki S, Martikainen M. (2013) Pre-hospital airway management by non-physicians in Northern Finland — a cross-sectional survey.. Acta Anaesthesiol Scand. May;57(5):654-9

Rechner JA, Loach VJ, Ali MT, Barber VS, Young JD, Mason DG. (2007) A comparison of laryngeal mask airway with  facemask and oropharyngeal airway for manual ventilation by critical care nurses in children. Anaesthesia. 62:79.

 Stone, BJ., Chantler, PJ, Baskett, PJF. (1998) The incidence of regurgitation during cardiopulmonary resuscitation: a comparison between the bag valve mask and laryngeal mask airway Resuscitation 38 3–6

Walsh K, Cummins F, Keogh J, Shorten G  (2000) Effectiveness of mask ventilation performed by hospital doctors in an Irish tertiary referral teaching hospital. Irish Medical Journal 93(2)

Wang, H., Mann, N., Mears, G., Jacobson, K., Yeal, D. (2011) Out-of-hospital airway management in the United States Resuscitation, 82 (2011) 378–385