In true FOAMed style, the organisers of the Graz summer school in POCUS have offered their handouts free for download.
In a similar vein, the WINFOCUS abstracts, 128pages of information!
And this set from Ultrafest,
well worth lesson, this is a presentation at SMACCDUB from Resa Lewiss, a real promotor of POCUS through her work with WINFOCUS and PURE
If you want more, she also talks in this Jellybean podcast with Doug Lloyd (only on Soundcloud, no download)
Probe positioning is very well defined for echocardiograpy, FAST and vascular scanning. However with the thorax there is a lot of real estate, and a lot of lung. Is there an agreed plan and language for scanning the lungs?
First a surface anatomy refresher:
For lung ultrasound assessment for assessment of interstial oedema there seems to be two main methods, following Volpicelli (Italy)or Lichenstein (France). Great slides by Lichenstein here.
First I present the 4 lung zones for each hemithorax described by Volpicelli from 2006:
With two zones anteriorly and two under inferior to the axilla. Different articles seem to variously place the horizontal line at the 3rd or 5th intercostal space.
And the three zones of Lichenstein and the BLUE (Bedside Lung Ultrasound In Emergency) protocol (really six as they divide the three zones into upper and lower, without setting out anatomical borders for upper/lower) from 2008.
In 2008 there were also two of the Italian workers Copetti & Cattarossi who described POCUS zones for paediatric lung infections were “The probe was placed perpendicular, oblique and parallel to the ribs in the anterior, lateral and posterior (lower and upper) thorax.”, creating six zones on each hemithorax, they don’t provide any guiding images.
Then there are various EM/ICU/CC/Anaesthesia protocols eFAST, RUSH, CCUS,FATE, F-LUS:
If you want to really wig out there is a 28 zone protocol to use:
I really just like this pragmatic approach:
What will I be using in general practice? As per my positioning post, clothing access and patient positioning and room ergonomics play a large part of the scanning process for me. The questions I want to address pneumothorax yes/no, B-lines/interstial oedema yes/no, consolidation yes/no and effusion yes/no would be well answered by any of these however the CCUS five zones (1R, 2R, 3R, 4R, 5R) modification of Volpicelli’s zones seems clear and allow me to have a re-producible note for myself in the patient record and onscreen comments for review scans. For on-referred patients (usually going to the ED for LRTI) I will still use word descriptors because we do not yet have a lingua franca for lung ultrasound zones.
I have not talked about probe selection or probe orientation (mostly perpendicular to ribs to achieve the Bat Wing sign, the FATE low pleural views are parallel to ribs to view lung/diaphragm/liver or spleen) or lung scoring systems.
Another learning point from my reading around these zones was something I have not been doing – scan low on the back to get kidney and then work up when patient is sitting. You will ensure you are low, below diaphragm and as you scan up in area 5R you give yourself the best chance of spotting the curtain sign of the diaphragm and then a dependent effusion.
Traditional sonography has the patient on a examination couch, usually in the centre of the room with machine on the patients right. POCUS in the ED can replicate this, or for procedures have the screen on the patients left, operator on the patients right however access around the patient on the hospital trolley bed is preserved.
In general practice we are often more constrained. Rooms can be small, beds are often fixed or too heavy to move easily and if not electric can be hard/unsafe for the elderly to climb.
Time constraints of a consultation also come into play – it can take a very long time for someone in winter layers to take everything off, lie down on the examination couch and then dress again.
So for pure reasons of anatomical access, safety, timeliness and privacy there are some scans that just need to go to the formal sonographer due to pure patient positioning reasons.
I have also been using a sitting position for lung POCUS, the patient sitting sideways on a chair without arms, allowing access to the back and infra-axillary lung windows. This however must affect rib spacing and ?increased lower zone consolidation compared to the ideal lying down with hands behind head in a trolley. Some articles do suggest a lying or sitting position equally valid and points out that sitting is preferred for the very dyspnoeic. This is another article from a early researcher/adopter of LungPOCUS, Volpicelli, who states there is no difference in lying/sitting/standing as fluid shifts occur slowly in the lungs.
Despite some discussion about benefit of imaging guided versus non-guided injection of the greater trochanter, I have swapped from a non-guided to guided approach as the Trochanteric Bursa is a good location to experience probe and needle control skills to assist with trickier areas like shoulder and knee.
For the elderly infirm, getting to the practice and then on to pathology/radiology can be a real expedition for the patient and the family. GP’s are perfectly poised to be doing this for the select patient.
Was the SOB COPD or CCF? a quick look with the US confirmed the clinical suspicions with oedema in Zones 2 left, Blines (lung rockets)
and Zone 3 left:
Similar picture on the right, so fitting more with a picture of mild interstitial oedema than COPD and ACEI/Beta Blocker directed therapies.
(patient consent for image and photograph use was obtained)