Ultrasound Guided Peripheral Vascular Access

Cite this article as:
Trent Calcutt. Ultrasound Guided Peripheral Vascular Access, Don't Forget the Bubbles, 2021. Available at:
https://doi.org/10.31440/DFTB.23253

One of my favourite things in paediatrics is the expanding role of ultrasound guided vascular access.

When I started as a paediatric registrar, I’d just finished an adult ICU term where I’d become spent a majority of time supporting provision of a vascular access service, and as part of this had become a PICC line insertion instructor. Eventually, I got to the point where I dreamt of abstract grey shapes. But then I started a paediatric job in a regional hospital where it seemed that ultrasound was used for vascular access rarely if at all. Initially, I thought there must have been something different about paediatric vascular access that I was unaware of. One day, when looking after a young lady with Rett’s who was known to be difficult to cannulate, I reached for the ultrasound. In the five years since, ultrasound has been a standard part of my practice in achieving vascular access in children, with technique adapted to fit the age of the patient.

Ultrasound-guided vascular access and paediatrics seem like such a natural partnership. The concept of a DIVA (“difficult IV access”) patient is receiving increasing interest and research. Criteria for a DIVA can include prematurity, inability to see or feel a vessel, or an episode of multiple prior attempts. These criteria would be met by a huge number of the kids we care for, in particular toddlers or the previously premature infant. 

Chonky baby arm
Spot the veins

Why is ultrasound not the first-line adjunct in these tricky kids? It’s probably multifactorial, but certainly, ultrasound is more difficult in children than adults. Its utility is varied in the NICU context and for infants under 2.5kg, although can still have a role with a modification to technique. It’s also harder to learn ultrasound in a population who are scared, angry, impatient and poorly tolerant of a prolonged period of needle-through-skin. For these reasons, I think that there is less appeal to replace the familiar (cannulating without an ultrasound), with the unfamiliar (cannulating with an ultrasound). As I’d experienced, this also leads to a culture where ultrasound is infrequently utilized, decreasing the likelihood of implementation by new or more junior staff.

Once the learning investment is made to reach a proficient level of ultrasound competency (about 20 cannulas in adults) the potential benefits are significant. Decreased time spent performing a procedure, decreased number of attempts and subsequent patient trauma, and increased cannula longevity are all achievable.

I’ve spent a lot of time thinking success optimisation in paediatric ultrasound guided cannulation, both during my own development of proficiency and then in an effort to verbalize this skill when educating others. Below are my 5 top tips to enhance your ultrasound-guided cannulation skills:

I’m hoping that some of these words may help avoid some bits of the inevitable trial and error process that comes with learning a new skill.

There is sometimes a general impression of both practical and personal inconvenience in using ultrasound for vascular access. An ultrasound may not be nearby. There is the fear of “looking silly” in front of other people, as turning on, adjusting, and then physically coordinating the use of the ultrasound may be unfamiliar. During the period of establishing proficiency, an approach to decreasing this sense of unfamiliarity is to get in the habit of bringing the ultrasound with you do a cannula. Turn on and optimize the ultrasound to view vessels, and spend a period mapping out candidates for cannulation using your non-cannulating hand. Draw on the patient with a skin pen if you want to keep track of the best sites. Then, discard the ultrasound and cannulate using whatever technique is most familiar to you, but with the added knowledge of vessel location, depth, size, and direction. If this becomes a routine and almost ritualistic process, the mental barrier created by a lack of familiarity with ultrasound settings and holding the transducer should decrease over time. It is a relatively small step from performing vascular mapping to placing a cannula under real-time ultrasound guidance.

The preparation otherwise is quite straightforward. In addition to the set up that you use for all other cannulas, you need the following four things:

  • An ultrasound with a linear array probe (the smaller the footprint and the higher the frequency, the better)
  • Sterile lubricating gel and some form of sterile barrier to cover your probe (this varies institutionally)
  • Cavilon wipe or skin prep (securement devices / dressings / tape doesn’t like to stick to ultrasound gel so will need some encouragement)
  • An extra person (one of your hands is out of action, so you need an additional person to perform the task that your non-dominant hand would normally do; this is typically stabilization of the distal limb)

The ultrasound sits on the opposite side of the bed to the operator, so as to minimize truncal movement in looking from the puncture site to screen. Aside from making sure the correct probe is selected, the only 3 settings you need to know how to adjust are depth (typically as shallow as possible), gain (similar to a ‘brightness’ setting to highlight blood-filled vessels), and a midline marker (for physical-digital landmark referencing).

As alluded to above, pre-scanning is a useful skill even in the absence of cannulating under real-time ultrasound guidance. It’s a good idea to scope out the most appropriate vessels and puncture sites prior to picking up your cannula. Essentially the objective is to place a cannula within a vessel with as few attempts as possible, as quickly as possible, with as little pain as possible, and in a site that will provide the greatest longevity. Characteristics of vessels that tend to correlate with these outcomes are:

  • long and straight stretches
  • vessel 6mm or less below the surface
  • vessels greater than 2mm in diameter
  • vessels that don’t cross a joint (provides freedom of movement and less extravasation)
  • vessels without upstream thrombosis or obstruction

Mid-forearm vessels often meet the above criteria.

The greater length of cannula able to be placed within the vessel can correlate with longevity, however larger cannula diameter may increase the phlebitis and decrease longevity. This requires consideration of the balance between length and diameter of device. Of the commonly available devices, a good balance is a blue cannula (22G). There are several specialised less widely available devices that are longer versions of small diameter cannulae (24G and 22G).

In practical terms, to find these vessels you can start in the antecubital fossa (more familiar area for most of us) and track them down, or plonk down on the forearm and pan circumferentially. Scanning in the short axis / transverse axis / cross-sectional view tends to work best in kids. To assess suitability, translate the probe up and down along a vessel to get an idea of the direction. If it’s running diagonally, rotate your probe until it’s running along the same plane as the vessel to act as a mental reminder of the angle/direction that you need to insert your cannula. Pick the specific spot on the vessel that you’d like to puncture, bearing in mind that you will be puncturing the skin millimetres back from that point. Pick the patch of the vein that is the longest, straightest, shallowest, and biggest. Have a second fallback site planned out elsewhere for if required. Lastly, make sure to track the vein proximally as far as you can to ensure that it doesn’t run into a large thrombosed/occluded/recannalizing patch of vessel.

Obscure angles make things more challenging, in my experience. Right angles and parallel lines are your friends because they assist in mental unburdening and allow you to devote energy to troubleshooting issues. As mentioned above, map the vessel prior to puncture. Part or all of a vein will often wander diagonally along its journey, so approaching from the wrong direction increases the likelihood of punching through the side of the vessel. The centre of the image corresponds to the arrow/marker along the long edge of the probe, so you have a reference point between digital (screen) and physical (skin). Use the ultrasound as a mental reminder of your plane of approach; rotate the probe until the vessel is consistently sitting in the very centre of your image as you plane up and down. In other words, the ultrasound image is perfectly perpendicular to the plane of the vessel.

Speaking of right angles, I prefer to keep the ultrasound at right angles to the surface that you’re scanning. Angling back and forth creates a loss of contact and a distorted image as the ultrasound bounces of structures and does not return to the transducer. This creates a less clear image where vessels artificially look larger. If you need to change your view, translate/glide the probe along the skin, rather than introducing angle. It can be useful to temporarily angle the transducer perpendicular to the shaft of the cannula if you lose sight of it as this will light it up more clearly.

This is a big one. Thinking of your cannulation as a two-phase puncture process is something that I find extremely helpful. Your objective is not to puncture the skin and end up inside the vessel in a single action, and in fact, attempting to do this seems decrease the likelihood of success. 

 

Puncture Phase 1

Puncture 1 is the process from skin puncture to positioning the tip of your cannula on the superficial wall of the vessel. To achieve this, align your probe to achieve a view with the vessel in the centre of the image. Puncture the skin with the cannula a few millimetres distal to the probe. This bit is painful, so do this with a decisive action so that 2-3 mm of the cannula is within the soft tissue. Increase your angle of insertion to 30-45°. Your next objective is to find the tip of the cannula. Moving your non-dominant (ultrasound) hand, translate/slide the probe towards the puncture site until a glimmering white dot becomes apparent in your image. Once you are convinced that you are viewing your cannula, you need to ensure that you are viewing the tip at all times.

The most important thing to remember is the only way to be certain that you are viewing the tip of your cannula is when the glimmering dot disappears when you move the probe 1mm proximally (away). It is frustratingly easy to think that you are viewing your cannula tip when instead you are halfway along the shaft, with the tip out the deep wall of the vessel. Maintain this view via a “walking” approach. For each 1-2mm advancement (step) of the cannula, make an equivalent proximal movement with your ultrasound probe (step). Move the ultrasound away so that you cannot see cannula tip anymore, and then advance the cannula into view. If needed, intermittently stop advancing your cannula and check your tip position as described above. I find advancing at 30-45° until you reach the vessel works well as minimal cannula is wasted on the journey there.

If you find yourself wandering off track, keep the ultrasound focused around the vessel as the centre of your image (as this is your target). Correcting if off centre is slightly counterintuitive. Move your cannulating hand away from the direction that you want to move your cannula tip (ie- moving right will move the tip left). Continue inserting until your cannula tip is sitting at 12 o’clock on top of your vessel. As you reach this point, the tip of the cannula may gently tent the roof of the vessel, turning an “O” shape into a “❤️” shape. This is a good test of correct positioning. Once you’ve reached this point, you’re ready for puncture phase 2!!

 Puncture Phase 2

Puncture 2 is the process of entering the vessel to feeding your cannula fully in. With the tip of your cannula in view and the roof of the vessel tented (❤️), continue incrementally advancing your cannula with tiny movement, walking the ultrasound forward to ensure the tip remains in view (as above). Gently decrease your angle of insertion so that the superficial wall is not tenting towards the deep wall but rather into the potential space of the proximal vessel. Eventually, your tented vessel (❤️) will suddenly encompass the cannula and return to a circular shape (O). This may be associated with a tactile pop. You can check for flashback for additional confirmation of vessel puncture, but I prefer to not take my eyes off the ultrasound screen at this point.

Continue decreasing your angle of insertion to maintain the tip of the cannula in the top 50% of the vessel (keep the sharp bevel away from the deep wall). This may eventually require you be pushing the cannula into the skin, which really requires your assistant to get out of the way. Don’t lose site of your tip! Continue to step forward; cannula then ultrasound. To check whether you are in the vessel and not in soft tissue or dragging on the vessel wall, waggle the tip of the cannula around gently (left, right, up, down). There should be absolutely no distortion of the soft tissue surrounding the vessel; completely free cannula tip movement. I tend to leave the metal stylet in until the plastic catheter is fully inserted to the hub because of greater visibility and added rigidity. This does, however, carry the risk of puncturing the back or sidewall of the vessel if you don’t keep a close eye on your cannula tip. At the very least, ensure 3-4mm of the cannula is inside the vessel lumen prior to gliding the plastic catheter off (to avoid tissuing / tearing the vessel roof). Once this is done, you’ve just successfully place a real-time ultrasound-guided cannula! Well done!

I think it’s reasonable with each healthcare interaction to measure success both in the resolution of issue (beneficence) and in minimization of harm / traumatic experience (non-maleficence). Vascular access is our commonest painful procedure, hence representing a significant potential burden of pain, anxiety, and trauma. Undertaking steps to minimize vascular access attempts, maximize speed/efficiency, and maximize cannula longevity are important considerations in the healthcare interaction. Even if we manage to achieve the elusive goal of a single puncture hospital admission, this still requires a single puncture. 

This discussion is not really directed towards addressing the specifics of analgesia and sedation but suffice to say that time permitting these should be used and optimized readily. A topical anaesthetic is valuable, although in the case of an ultrasound-guided cannula application by the operator is useful in ensuring good placement. Evidence is increasingly suggesting that topical anaesthetic is appropriate in all ages including neonates.

The power of social stories, rehearsal, music therapy, and just general distraction cannot be undervalued. There is a multitude of approaches to this. 

Unfortunately, it is not an uncommon experience to be in a situation where vascular access is required with a degree of clinical urgency. In this circumstance, oral/intranasal/topical medication may have not had time to work, and a specialist in distraction may not be readily available.

In this circumstance, I have found that playing calm and quiet music more useful than positioning a video in front of a child. Maintaining a minimum of people speaking, and using quiet calm voices is valuable. I have had some success using the ultrasound itself as a distraction modality while telling the child a story of the “doughnut that has lost its hole” (vein and cannula tip respectively) as the tip tracks toward the vessel. A variant is the “star that fell from the sky into the lake” (cannula tip and vein respectively). There are many approaches to pain reduction through distraction.

It is my sincere hope that these tips are of some practical and clinical value in your cannulating endeavours. If it makes a difference for a single child, then surely it’s worth it. Good luck!

The 49th Bubble Wrap

Cite this article as:
Currie, V. The 49th Bubble Wrap, Don't Forget the Bubbles, 2021. Available at:
https://dontforgetthebubbles.com/the-49th-bubble-wrap/

With millions upon millions of journal articles being published every year it is impossible to keep up.  Every month we ask some of our friends from PERUKI (Paediatric Emergency Research in UK and Ireland) to point out something that has caught their eye.

Article 1: The associations between initial serum pH value and outcomes of paediatric out-of-hospital cardiac arrest

Okada A, Okada Y, Kandori K, Nakajima S, Okada N, Matsuyama T, Kitamura T, Hiromichi N, Iiduka R. Associations between initial serum pH value and outcomes of pediatric out-of-hospital cardiac arrest. Am J Emerg Med. 2021 Feb;40:89-95. doi: 10.1016/j.ajem.2020.12.032. Epub 2020 Dec 17. PMID: 33360395.

What’s it about? 

This paper reviewed the association between initial pH, obtained via intra-arrest VBG, and patient outcomes to evaluate if pH can be used to prognosticate in paediatric out of hospital cardiac arrest.

The authors reviewed a large, multicentre, prospective register of out-of-hospital cardiac arrests in 87 hospitals in Japan. They included paediatric out-of-hospital cardiac arrest patients younger than 16 between June 2014- December 2017 (458 patients included in the analysis – however over 35,000 listed in the registry). The primary outcome was 1-month survival. They divided the patients into four groups (based on initial pH on blood gas) and compared this to the patient’s ultimate outcome.

Interestingly, the median age of the patients was one year of age. Just over 6 in 10 of the patients were male. In 7 out of 10 patients, the first monitored rhythm was asystole. Cardiogenic arrest occurred in 4 out of 10 patients.

Mortality, and survival with good neurologic function, were lookd for. The overall survival rate at one month was just over 1 in 10 patients. In the group with pH > 6.82 survival rate was around 4 in 10 patients. However, with a pH< 6.47, thesurvival rate was 1 in 100 patients.

Of particular interest, in the entire study population of 458 patients, there were no patients who survived with good neurological function with a pH <6.8.

Why does it matter? 

Deciding when to stop resuscitation in a paediatric cardiac arrest can be difficult. Guidance is sparse and there are no universally recommended measures to help providers decide when to stop resuscitative measures. This is a stark contrast to adult cardiac arrest management where there are many validated termination of resuscitation rules based on measurements such as end-tidal CO2 s.

This is the first study to assess the association between pH and prognosis in paediatric out-of-hospital cardiac arrest. It presents robust evidence to support an objective, easily obtained measure that can be used to assist decision making around the termination of resuscitation. Important exclusions in this study were patients where resus was not attempted at a hospital, unknown age, traumatic or arrest secondary to hanging and those with no pre-hospital data.

This is an exciting paper providing guidance in an area sorely lacking any previous data. It gives providers a valuable tool that can substantially assist when making a difficult decision.

Clinically Relevant Bottom Line:

In out of hospital paediatric cardiac arrest, according to this study, no patients with a pH <6.8 survived with a neurologically favourable outcome. Survival in general was significantly lower in patients with an initial pH <6.8.

Reviewed by: Sean Croughan

Article 2: Should we be using focused cardiac ultrasound to guide therapy in children with sepsis?

Arnoldi s, Glau CL et al. integrating focused cardiac ultrasound into Pediatric septic shock assessment. Pediatr Crit Care Med. 2021 mar 1;22(3):262-274

What’s it about? 

This paper looks at whether the integration of FCU (focused cardiac ultrasound) in clinical assessment of children with sepsis would alter clinician’s evaluation of their haemodynamic characteristics.

The authors conducted a retrospective, observational study from January 2014 – December 2016 in a large PICU in America. They reviewed 74 PICU patients who received FCU within 72 hours of sepsis pathway initiation. Assessment by clinicians prior to FCU was compared to assessment after FCU in 46 patients, to determine if there was a difference in the haemodynamic characterisation of patients.

They demonstrated that incorporation of FCU changed the clinician characterisation of haemodynamic assessment made prior to FCU in more than 2 out of 3 of cases. The most common new finding identified post-FCU was myocardial dysfunction in (7 out of 22) cases. The most commonly ruled-out physiologies by clinician after FCU performance were obstructive physiology (5 in 8 cases), fluid responsiveness (13 in 26 cases).

Why does it matter? 

Sepsis in children continues to be one of the leading causes of mortality and morbidity worldwide.  Most children who die of sepsis suffer from refractory shock and/or multiple organ dysfunction within the initial 48 -72 hours of treatment, thus demonstrating the need for early and targeted interventions.

The previous method of classifying patients as having either ‘warm shock’ or ‘cold shock’ to guide therapy has been demonstrated to have poor correlation with cardiac function and systemic vascular resistance, and has not led to improved outcomes. It is now recommended that more advanced techniques such as focused cardiac ultrasound (FCU) be used alongside clinical assessment to identify haemodynamic status and direct therapy.  This is already widely the case in adult practice and algorithms have been created for its integration into patient management. 

Although this is a small study, it makes us think about the use of cardiac ultrasound alongside clinical assessment of children with sepsis in order to understand the haemodynamic characterisation of these patients.

This may be particularly useful in relation to fluid responsiveness, as half of the children who were thought to be fluid responsive pre-FCU, were found not to be after a FCU was performed. We know that children with sepsis often receive significantly more fluid per kilogram than adults which is associated with worse outcomes.

Clinically Relevant Bottom Line:

FCU, when incorporated into shock assessment, has the potential to identify myocardial dysfunction earlier and could result in reduced fluid administration as well as more targeted therapy based on haemodynamic status. However, further work is needed to determine how this can be used within paediatric practice.

Reviewed by: Laura Duthie

Article 3: Don’t forget the planet

Di Cicco, M.E., Ferrante, G., Amato, D., Capizzi, A., De Pieri, C., Ferraro, V.A., Furno, M., Tranchino, V., La Grutta, S. (2020) Climate Change and Childhood Respiratory Health: A Call to Action for Paediatricians. Int J Environ Res Public Health, Vol 24;17(15):5344

What’s it all about?

The authors conducted a systematic review looking at papers which examined the connection between respiratory illnesses in children aged 0 – 18 years. Keywords used separately and in combination were (allergic rhinitis, rhinitis, asthma, bronchitis, pneumonia, infections) and key environmental phrases (climate change, pollution, particulate matter, ozone, nitrogen dioxide, allergen, pollen). There was no limitation on the date of paper or country of origin.

Whilst much of the research at this stage is not completely conclusive key points from the review include:

  • Several studies from different countries found a connection between the increased prevalence of rhinitis and asthma, as well as the frequency of symptoms with increased global temperatures, which has changed many plant species’ lifecycles and led to longer pollen seasons
  • Positive correlations between the incidence of pneumonia and other acute respiratory tract infections in the context of increased extreme weather events such as heatwaves, fires and floods
  • Positive associations between the increased relative humidity and increased activity of respiratory viruses such as respiratory syncytial virus

Why does it matter?

Climate change is the long-term shift in weather conditions (temperature, humidity, winds and extreme weather events) and is often talked about in regards to protecting our wildlife or preventing further damage to our oceans and forests. It is less talked about when considering the impact on our own health. A child born in 2020 will live in a world that is more than 4 degrees warmer than the pre-industrial average, and subsequently will be at greater risk of a variety of acute illnesses as well as long term health consequences.

The Bottom Line:

More research needs to be done to accurately define the burden of climate change on our health. In the interim, we can all be environmental champions, from making changes in our own lives to reduce our carbon footprint as well as educating and influencing our colleagues and patients to do the same.

 …And for those with spare time; conducting research into the direct effects of climate change on specific health conditions along with contributing to government policies to create change at a higher level and reducing the carbon footprint of our healthcare systems are excellent places to start! 

Reviewed by: Tina Abi Abdallah

Article 4: Domo arigato, Mr Roboto

Littler BKM, Alessa T, Dimitri P, et al Reducing negative emotions in children using social robots: systematic reviewArchives of Disease in Childhood  Published Online First: 08 March 2021. doi: 10.1136/archdischild-2020-320721

What’s it about?

The paper looks at a number of studies that have used social robots in paediatric outpatient settings to interact and provide multi-sensory experiences to patients. The author postulates that using social robots provides better interaction and distraction for children, thus reducing anxiety and distress during the visit.

This systematic review managed to find ten studies that used social robots ranging from humanoid-based robots to ones simulating toy bears, dinosaurs and seals. The robots interact verbally and physically, and can respond to patient cues and tactile stimulation. They were used before or during the intervention. The studies included randomised controlled trials, exploratory trials, pilot and an observational study, with patient numbers varying from 2 to 73 (320 in total).

Why does it matter?

For lots of children a visit to the hospital can be a stressful and anxiety inducing event. There has been research to suggest that social robots have a positive impact on supporting adults with dementia and in children with autism they have been a useful tool in conducting therapy. The outcomes of this study were measured by observation, and by recording levels of distress, anxiety, pain and emotion using a variety of behavioural questionnaires. Overall, the feedback from the studies showed positive engagement from patients with their robots, reducing negative emotions, distress and pain.

The bottom line

There is promising data to suggest that robots may improve the experience of children in the healthcare environment. However, the evidence is weak due to the nature of the studies, lack of uniformity in the measurements, and low patient numbers. More research is needed on this topic to be able to really change practice but this sci-fi intervention may well become a reality in the not so distant future.

Reviewed by: Laura Riddick

Article 5: Children visiting the Paediatric emergency department during Ramadan

Sawaya,R., Wakil, C., et al (2021) Pediatric emergency department utilisation during Ramadan: a retrospective cross- sectional study. Archives of Disease in Childhood 2021;106:272-275.

What’s it about?

 This study looks to investigate the impact of Ramadan on patient characteristics, diagnoses and metrics in the paediatric emergency department (PED). There is limited data on how Ramadan impacts paediatric ED’s.

Why does it matter?

The authors looked at patient and illness characteristics as well as PED metrics including peak patient load, presentation timings, length of stay, time taken to order tests, receive samples and reporting of results to see how these were affected during the months of Ramadan and those before and after. 

This is a retrospective cross-sectional study on paediatric patients from 0 – 18 years presenting to a PED tertiary centre in Lebanon. Data was collected from all PED visits with any complaint at any time during Ramadan and the months (30days) before and after in 2016 and 2017. A bivariate analysis was performed between the Ramadan and non-Ramadan groups. The main outcomes were illness severity, chief complaints, final diagnoses, PED metrics including peak patient load, presentation timings, length of stay, and PED efficiency metrics such as time to order tests, times to samples being received and reported. 5711 patients were included and 1672 of these presented during Ramadan. There was no significant difference between age, gender or illness severity between the Ramadan or non-Ramadan group. This study found a significant difference in the number of GI complaints during Ramadan (39%) compared with the non-Ramadan group (35%). 

Trauma related complaints increased during Ramadan (3 in 100) vs (2 in 100) in non-Ramadan periods. Especially during the non-fasted periods of Ramadan (4 in 100) vs (2 in 100) during the fasted period of Ramadan. The number of daily visits during Ramadan (28.3) was reduced compared with non-Ramadan attendances (31.5). The Ramadan group did not have to wait longer for tests to be ordered or to have samples collected. 

This study was a single centre- and the charts that were reviewed did not have information on the patients individual fasting status. This would be interesting to see if the patient’s individual status affected diagnosis. The team used months immediately before and after Ramadan to reduce the confounding effects of seasonal bias.

Clinically Relevant Bottom Line:

This study revealed that there were some changes in GI and trauma presentations during the Ramadan period. There was also a reduction in cases presenting in this centre- this could help to influence staffing during this time if the patient population reflected that of the population in this study.

Reviewed by: Vicki Currie

If we have missed out on something useful or you think other articles are absolutely worth sharing, please add them in the comments!

That’s it for this month. Many thanks to all of our reviewers who have taken the time to scour the literature so you don’t have to.

All articles reviewed and edited by Vicki Currie

POCUS: Russ Horowitz and Cian McDemott at DFTB19

Cite this article as:
Team DFTB. POCUS: Russ Horowitz and Cian McDemott at DFTB19, Don't Forget the Bubbles, 2020. Available at:
https://doi.org/10.31440/DFTB.22174

Where would the world of paediatrics be without POCUS? We’d still be trying (and failing) to cannulate chubby toddlers by feel alone, we’d still be using radioactive waves to determine if the child in front of us has pneumonia and we wouldn’t have this eye-opening talk from Russ and Cian.

©Ian Summers

 
Russ and Cian co-ordinated the wonderful pre-conference ultrasound workshop in London.  Here is one of our favourite pearls is you want to help identify the bladder before performing a SPA. The bladder, looking just like a slice of toast, makes the perfect target.
 
 
 
If this talk has whetted your appetite then why not sign up for one of the www.dftb20.com ultrasound workshops.

This talk was recorded live at DFTB19 in London, England. With the theme of  “The Journey” we wanted to consider the journeys our patients and their families go on, both metaphorical and literal.

If you want our podcasts delivered straight to your listening device then subscribe to our iTunes feed or check out the RSS feed. If you are more a fan of the visual medium then subscribe to our YouTube channel. Please embrace the spirit of FOAMed and spread the word.

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Selected References

Sii F, Barry RJ, Abbott J, Blanch RJ, MacEwen CJ, Shah P. The UK Paediatric Ocular Trauma Study 2 (POTS2): demographics and mechanisms of injuries. Clinical ophthalmology (Auckland, NZ). 2018;12:105.

Imaging in COVID

Cite this article as:
Nuala Quinn, Cian McDermott and Gabrielle Colleran. Imaging in COVID, Don't Forget the Bubbles, 2020. Available at:
https://doi.org/10.31440/DFTB.24680

The current pandemic is providing a challenge in healthcare settings whose resources are rapidly becoming strained. From the early experiences in China, it appears that children who are infected with COVID-19 have a milder course typically than that seen in adults. The radiological findings in adults include multifocal bilateral ground-glass opacities and consolidation. This is often peripheral or basal in distribution. They tend to evolve from either these bilateral ground-glass opacities on the periphery to consolidation then crazy paving. The limited initial data in children suggest that multi-lobar involvement is much less common. This is consistent with the hypothesis that children appear to have milder disease. Findings peak at 7 to 14 days and then gradually resolve. We do not yet know the radiologic sequelae.  Experience taken from the adult population in Ireland has also noted air leak complications including pneumomediastinum and pneumothorax. Pleural effusions, lymphadenopathy, and tiny lung nodules seem to be less common manifestations.

 

X-ray

The chest x-ray is, in general, the first-line imaging in children with respiratory pathology. And it is being used in COVID-19. This (pre-publication) CXR is from a case in a tertiary paediatric hospital. It shows bilateral mid-zone and left lower zone patchy consolidation and pneumomediastinum.

Ming-Yen et al describe five patients who had both chest x-rays and a CT of the thorax. Two patients showed normal CXR findings, despite having a CT examination on the same day showing ground-glass opacities. The positive CXR findings seem to appear later in the disease progression. Within the Guangdong province of the authors, a CT of the thorax is now being requested on every patient suspected of having COVID-19 regardless of risk. However, the radiation associated with CT in children does not, and cannot, support this in the paediatric setting. In sticking to the ALARA (As Low As Reasonably Achieivable) we should consider the use of another evidence-based resource – point-of-care ultrasound (POCUS).

Point of care ultrasound (POCUS) is fast becoming an established part of paediatric emergency medicine. Lung ultrasound is a mainstay of POCUS for a variety of diagnoses including pneumonia and pleural effusion. Now, there is rapidly evolving evidence on COVID-19 and POCUS lung findings.

So, how do we use ultrasound to look for ground-glass opacification and consolidation in children with suspected viral respiratory tract infection?

 

Sonographic characteristics

 

Lung US is more sensitive than CXR for interstitial patterns, small effusions, and subpleural thickening. The POCUS characteristics are similar to other causes of viral pneumonia, but in COVID-19, two studies (Huang et al and Peng et al) also described localized pleural effusions. They are more often seen with bacterial pneumonia in children, rather than viral. Large volume pleural effusions are uncommon – if you are seeing this then you need to consider other pathology.

B-lines are short-path reverberation artefacts that are found in many pathological and nonpathological states. *ISP is interstitial syndrome pattern, i.e. extensive B lines which may coalesce. This pattern is not unique to COVID-19. It is also commonly seen in pulmonary oedema. In COVID-19 these may appear in characteristic focal, multifocal and confluent patterns.

Small subpleural consolidations may be also seen. These are small hypoechoic areas inferior to the pleural line. If there is bibasal consolidation on the ultrasound, there may also be dynamic bright air bronchograms present. In COVID-19, a pleuropathy develops. This results in a thickened, irregular appearance of the pleura. There may also be skip lesions – normal pleura alongside thickened pleura with associated B-lines.

It is important to note that children may be clinically well with any of the positive lung POCUS findings.

Technique tips

The technique for POCUS lung is well described. However, for children and COVID, the following may be helpful:

  • Use the linear probe to assess pleura and look for pleural line thickening, small superficial effusions, skip lesions and B-lines.
  • Use the curvilinear or phased for lung windows. It may also be better for posterior pathology such as consolidation and air bronchograms.
  • Turn off the harmonics and spatial functioning.

And if you don’t know what any of that means then head over to Practical Pocus for a free online course and follow @Zedunow for their daily updates.

 

Decontamination and machine preparation

Infection control measures are key – the machine should go in clean and come out clean! ACEP have published an excellent COVID US cleaning protocol which is really worth a look at.

Remember to strip the machine of all non-essential items such as trays, holders and inserts and where possible avoid keyboards and use the touchscreen. Rather than multi-use bottles of gel, you should be using single-use sachets.

Handheld devices provide an alternative, with less cleaning required.

 

Photo courtesy of Cian McDermott

A word on CT

The CT findings associated with COVID-19 have been widely described: ground-glass opacities and consolidation with or without vascular enlargement, interlobular septal thickening ,and air bronchograms. Most of the studies are in affected adults and the high reported sensitivity will be affected by patient selection bias. Like the chest x-ray, it may be falsely negative in the first few days of illness. A normal CT early in disease could be falsely reassuring. Indeed, the general guidance from numerous faculties of radiology does not currently recommend CXR or CT to diagnosed COVID-19. Viral testing remains the gold standard.

 

Finally, a word on ALARA

ALARA, or making every effort to limit exposure to radiation As Low As Reasonably Achievable, is particularly relevent in COVID-19. Imaging should only be conducted for those patients where imaging will impact management of the condition. These recommendations may change as our knowledge of COVID evolves. CXR, CT and POCUS each have their own limitations, but there is emerging evidence that POCUS, in the hands of a competent practitioner, is superior in ease of access, diagnostic ability and ease of decontamination, particularly at a time when infection control is so crucial.

 

Selected references

Kanne JP, Little BP, Chung JH, Elicker BM, Ketai LH. Essentials for Radiologists on COVID-19: An Update-Radiology Scientific Expert Panel. Radiology. 2020 Feb 27:200527. https://pubs.rsna.org/doi/pdf/10.1148/radiol.2020200527.

Liu M, Song Z, Xiao K.High-Resolution Computed Tomography Manifestations of 5 Pediatric Patients With 2019 Novel Coronavirus.J Comput Assist Tomogr. 2020 Mar 25.

Ming-Yen N et al. Imaging Profile of the COVID-19 Infection: Radiologic Findings and Literature Review. Radiology 2020 Feb 13 https://doi.org/10.1148/ryct.2020200034

Huang Y et al. A Preliminary Study on the Ultrasonic Manifestations of Peripulmonary Lesions of Non-Critical Novel Coronavirus Pneumonia (COVID-19) SSRN 2020 Feb 28 https://dx.doi.org/10.2139/ssrn.3544750

Peng, Q., Wang, X. & Zhang, L. Findings of lung ultrasonography of novel corona virus pneumonia during the 2019–2020 epidemic. Intensive Care Med (2020). https://doi.org/10.1007/s00134-020-05996-6

Li Y, Xia L. Coronavirus Disease 2019 (COVID-19): Role of Chest CT in Diagnosis and Management. AJR Am J Roentgenol. 2020 Mar 4:1-7. doi:10.2214/AJR.20.22954

 

International Society Guidelines

Royal Australian and New Zealand College of Radiologists

Canadian Association of Radiologists 

American College of Radiology statement on CXR and CT findings in COVID19

Royal College of Radiology statement on CT in COVID

We’ve only just begun…

Cite this article as:
Andrew Tagg. We’ve only just begun…, Don't Forget the Bubbles, 2019. Available at:
https://doi.org/10.31440/DFTB.19490

As we prepare for the opening of #DFTB19 and meeting friends from all over the world it’s great to see everyone getting stuck into the workshops.

The Compassion Lab

Mary Freer is the Fairy Godmother of the DFTB conferences. Since she spoke at DFTB17 we have been awed at her passion for compassion. This year she ran a boutique Compassion Lab to help bring a little more kindness to our workplace.

In our time poor, resource poor workplaces it can be a challenge to be kind, both to ourselves, each other, and our patients.

If you couldn’t make it over to London then there are still some tickets left for her Compassion Revolution in Melbourne.

Presentation skills 2.0

We like to challenge our speakers to step out from behind the lectern and bring their ‘A’ game. This can be quite confronting when you are used to watching the usual ‘death-by-powerpoint’ type of talk. To make it easier for our speakers Grace Leo and Ross Fisher have, once again, acted as speaker coaches. But we didn’t want only just our speakers to benefit from their wisdom.

Over the course of the day they took delegates from the basics of the P3 methodology to the next level of presenting. We are really looking forward to hearing their pitches for next year.

The Power of POCUS

Ultrasound is the way forward in paediatric imaging and for our two workshops Cian McDermott and Russ Horowitz had an amazing team to help them. With the support of GE Healthcare and Jon Robinson delegates were rotated around a variety of stations to test their ultrasound chops.

They were joined by Resa Lewiss, Mike Griksaitis, Avi Sarfatti and Toni Hargadon-Lowe.

We were lucky to have some very patient paediatric models to tell our ultrascoundrels if they were pushing too hard or putting the probe in the wrong place. We even managed to come up with a new US sign – let’s hope the Toast sign of a full bladder catches on.

Let’s Play Make Believe

A crack team of simulationistas led by Ian Summers ran two sessions on Sunday. Starting with a simulation design workshop and ably abetted by Sandra Viggers, Camille Sorensen, Morten Lindkvist, Damian Roland and LifeCast the group were set the task of designing in situ simulation scenarios with the child in mind.

The afternoon session was led by Walter Eppich who took the delegates through the power of debriefing. He is a man who has spent a lot of time thinking about debriefing.

Bajaj K, Meguerdichian M, Thoma B, Huang S, Eppich W, Cheng A. The PEARLS Healthcare Debriefing Tool. Acad Med. 2018, 93(2), 336.

The day ended with another storytelling evening. Old friends and new gathered at the Sway Bay in central London to share tears and laughter.

What happens at Storytelling stays at Storytelling!

DFTB go to SMACC

Cite this article as:
Andrew Tagg. DFTB go to SMACC, Don't Forget the Bubbles, 2019. Available at:
https://doi.org/10.31440/DFTB.18334

Without SMACC there would be no Don’t Forget the Bubbles. But little did Tessa and I know that despite being at the same conference it would be another four years before we actually met in person at DFTB17 in Brisbane.

Nobody knew what to expect at that first SMACC as we sat in the dark waiting for the conference to begin.  I had just signed up with Twitter and was just excited to be in the company of people who thought the same as me, who were excited to learn, and were using this new thing called #FOAMed. As I am the shy retiring type I barely said hello to people that now, a lifetime later, I would be proud to call friends. Instead, I just sat in the audience and absorbed all the knowledge and positivity that flooded my way.

Flash forward a few years and those friendships, forged online, have grown as Twitter avatars are replaced with real people. No longer am I as shy to go up to someone I have never met in real life and I’m glad others have taken up the challenge too (Andrew and Sarah,  I am looking at you).

Tessa and I feel very privileged to have played some small part in the success of SMACC as we run the very final SMACCmini paediatric workshop. If you couldn’t come along then here are some of the things you missed.

 

Sweet Child O’ Mine (A neonates journey) – Trish Woods

Trish is no stranger to the DFTB ethos and as a neonatologist stopped to make us reflect on one of our basic assumptions – just who is the patient.  Just because our tiniest patients lie in their cribs, helpless, requiring help with all of their daily cares, does not mean that we should not consider them as people. It might be an alien thought to some – that the patient in front of us hears what we say, and how we say it, but they are not just a disease or a problem to be dealt with or the one in pod 3. They are a person with a name.

Seeing the team through the eyes and ears of the patient, Trish helps us enter the sensory (and often-overstimulating) world of the NICU.

Why not take a look at this paper on some of the ways we can start treating the patient and not the disease.

Roué JM, Kuhn P, Maestro ML, Maastrup RA, Mitanchez D, Westrup B, Sizun J. Eight principles for patient-centred and family-centred care for newborns in the neonatal intensive care unit. Archives of Disease in Childhood-Fetal and Neonatal Edition. 2017 Jul 1;102(4):F364-8.

I Want Candy (neonatal pain relief) – Justin Morgenstern

Justin Morgenstern, one of everyones favourite Canadians, has recently relocated to our side of the world and is practicing in New Zealand. Knowing that he is such a fan of evidence based medicine we set him the task of finding out if sucrose is as good as we think it is as an analgesic in neonates.

Here, for your delectation, is his take on analgesia for kids.

I don’t want to spoil his conclusion but this slide might give you just a little clue…

He started by challenging a fundamental assumption – that we can accurately tell whether a neonate is in pain or not. Or, more accurately, he challenged our assumption that we could tell when a medication worked.  We know the limitations of the traditional Wong-Baker Faces scale in older children and most of us probably use some combination of our clinical gestalt and the FLACC (Face/Legs/Arms/Cry/Consolation) score in neonates. But is it some sort of surrogate marker for distress, rather than pain? If fMRIs show no difference in an infants brain when they receive sucrose does that mean it does nothing for pain?

Of course there are a lot of things we can do that we know do work:-

  • Limit painful procedures
    • If venipuncture is less painful than a heelprick why not use it.
  • Let nurses treat the pain
    • Nurses are amazing (full stop) but they are also so much better at giving analgesia by the clock than any doctor
  • Address the underlying issues
    • Splint the obviously broken arm  before x-ray rather than waiting for them to get some imaging and then feeling guilty about it.
  • Consider non-pharmacological adjuncts
    • Dogs, clowns and bubbles are all powerful distractors.

 

Straight Up (bilious babies) – Camille Wu

Camille Wu last spoke for us at DFTB17 on testicular tribulations so it was a pleasure to welcome her back to join us to talk about surgical causes of bilious vomiting.

Rather than put words in a parents mouth she suggested asking exactly what colour was the vomit. If they answer Pantone 2565C then you are in trouble. Green vomit suggests a higher up obstruction that might require surgical intervention and certainly requires surgical assessment. Likewise rather than asking if the vomit was projectile, it is better to ask “How far did it go?

Whilst it is important to remember that there are a number of significant medical causes of bilious vomit (such as sepsis and CPAP belly) we really need to be concerned about surgical causes. Camille broke these down into mechanical causes and functional causes.

Mechanical causes

Intrinsic

  • Duodenal atresia
  • Small bowel atresia
  • Ano-rectal malformation

Extrinsic

  • Malrotation/volvulus
  • Congenital bands
  • Intestinal duplication

Functional causes

  • Hirschsprung disease
  • Meconium ileus/plug
  • Necrotising enterocolitis

The more proximal the obstruction the less bubbles of gas you will see on initial imaging. Camille reminded us that early imaging and intervention can make all the difference. If in doubt, pick up the phone, no matter the time of day or night.

The Safety Dance – Linda Durojaiye

Linda Durojaiye is a staff specialist at Sydney’s Children’s Hospital at Randwick. In her talk on leadership and patient safety she owned up to mistakes that have been made and shared some lessons from her department on how they have created a safer environment where everyone is accountable. Given that we have no control over who comes in we need to take ownership of what happens to them once they pass through our doors.

Linda and her team created a culture of safety – starting with regular team huddles to identify potential threats to safety. Using a strong leadership team they created a model of care that engaged both medical and nursing staff as well as the patient/parent consumer. She highlighted the resources freely available on the Institute for Healthcare Improvement website.

If you want to know more about the Clinical Emergency Response System then you can find it here.

 

One Vision (VR in paediatrics procedures) – Andy Weatherall

If your idea of virtual reality is still stuck in the last century and The Lawnmower Man (a poor 34% on Rotten Tomatoes) then you might not be aware of some of the advances that are putting the technology in the hands of normal people. Andrew Weatherall is the co-chair of paediatric anaesthesia at the Children’s Hospital at Westmead and has been looking at the role virtual reality may play as an adjunct to standard anaesthesia techniques.

He has written about his experiences here. Whether as a means to reduce anxiety before a procedure or as a distraction from the procedure itself virtual reality is no longer priced out of possibility. With Google Cardboard costing just a few bucks and lots of open source software available it won’t be long before we see more departments trying it out. We hope to hear more from Andrew and his team in the near future to see how they are going.

The Model (3D printing in paeds) – Jasamine Coles-Black

Carrying in on with technological advancements in paediatrics Jas Coles-Black from the 3D lab at the Austin in Melbourne made the audience realise just how affordable 3D printing can be. A technology that once cost six figures is now cheaper than the average consultants coffee habit. After a quick jaunt through the various methods of printing she went through some of applications relevant to paediatric practice. With printable task trainers costing just a couple of dollars (after the capital expenditure) we could all have our own paediatric can’t intubate – can’t oxygenate model. Or perhaps you want your trainees to learn how to ultrasound the neonatal spine to improve their success at lumbar puncture – a task trainee is yours for less than a latte.

3D printing can also be used to help patients understand complex ideas and a number of cardio-thoracic surgeons have used 3D printed models of congenital heart defects to help explain complex anatomy. We are looking forward to hearing more from Jas about this exciting technology and how it can benefit all of us. And, if people are interested, we could create our very own DFTB 3D printing workshop at a future conference.

Jas' favourite 80s movie

https://www.youtube.com/watch?v=1g3_CFmnU7k

(Yes – I know it was 1977 – Ed)

Sound and Vision (Critical care ultrasound) – Tom Rozen

SMACCmini was competing against the very practical paediatric ultrasound workshop but we couldn’t make it through without mentioning it at least once. Tom Rozen, intensivist at the Royal Children’s Hospital, used the example of René-Théophile-Hyacinthe Laennec’s (yes, really!) most famous invention, the stethoscope, to demonstrate how medical fashion has changed. A device that once took up an entire room can now fit in your pocket and with ultra-cheap, ultra-portable devices entering the market it will not be long before clinicians can have a device of their very own.

If you want to know what all the fuss is about then why not sign up for one of our pre-DFTB19 workshops.

Too Shy (20 minutes of bottom jokes) – Ross Fisher

Mr Fisher was set the challenge of making talking about constipation interesting and he succeeded. From his opening Limahl tribute to the crowd singalong he soon had us tapping our toes to the 1983 Kajagoogoo classic. He began by asking us to turn to the person sitting next to us and take a bowel history. After a round of sniggers a fair percentage of the delegates were unable to complete the task. Fortunately I was sitting next to Tessa and we know each others bowel habits intimately. If we are too shy shy to ask a grown up about what they get up to in the toilet no wonder we are pretty awful at asking children. Most children are all smell, noise and little substance in the bathroom so the only way to really find out what they are up to is to ask them, in their own language.

Constipation and its consequences can be stigmatising to a child and so the mindful clinician should sit and listen to the parent and their concerns, without judgement. Treatment can be a long and drawn out affair taking as long to fix as the child has had the problem for.  Take a look at our series on constipation here.

Faith (It takes a team) – Bec Nogajski

The final talk of the morning, by Bec Nogajski, brought it all together and reminded us of the importance of teaming. We’ve all been a part of dysfunctional teams and Bec challenged us to look at our role in the team, not as a passive sheep to be lead around, but as an integral unit with worth. There are many ways of finding out how you might fit in the team – Belbin’s team roles, DISC, Myers-Briggs (INTJ in case you were wondering) – but it is worth considering  that there is no perfect recipe for an effective team.

The team sets the behaviour, what is tolerated and what is not. As David Morrison said, “The standard you walk past is the standard you accept.” So do you check your mobile phone during clinical handover, and allow others to do the same or is this type of behaviour below the line?

 

 

Our eternal thanks, as always, to the SMACC OC throughout the years, especially, Chris, Roger and Oli who made such an impact on four aspiring paediatricians that they decided that they could run their own conference. If you want to see what all the fuss is about then there are still a handful of tickets left for www.dftb19.com in London, this June.