Case Based Learning in the New Year: pneumothorax & lung ultrasound

Last week we ran another case-based learning session. The session consisted of a short discussion based around a case that we were tasked that involved a patient with a suspected pneumothorax.

We discussed the issues and challenges of managing a patient on the ground and in-flight with a pneumothorax. In addition, we discussed then practiced how we can use ultrasound as an added tool in the diagnosis of a pneumothorax in the prehospital setting.

To briefly summarize, I’ve divided up some discussion points

Medical

  • Both paramedics and doctors discussed the most important aspect in the patient with a pneumothorax in the pre-hospital setting was the clinical status
  • The ultrasound was noted to be extremely helpful for diagnosis however, presence of pneumothorax didn’t necessarily warrant intervention
  • Clinical condition was the overwhelming driver for intervention. The question arose regarding the role of ultrasound – “if the presence of pneumothorax did not necessarily mean intervention required, why use it?” In general, clinicians felt that knowledge about the condition would help make subsequent decisions in the case of deterioration
  • One theoretical approach was proposed – in a patient with pneumothorax that was reasonably stable, consider anesthesitizing & exposing the site for a chest drain then proceed with finger thoracostomy if deterioration. Several clinicians felt that it there was such concern to proceed with local anesthesia then probably a drain should just be placed.
  • In the patient with a left sided pneumothorax, there was strong agreement that loading the patient feet first such that the clinicians would have access to the left side (of our typically starboard loaded patient)
  • The likelihood of needle decompression success is only 50% – brief discussion about an anterior approach vs. a lateral approach

Operational

  • Knowledge regarding pneumothorax is key depending on the location of the patient. In situations on the east coast of the Coromandel then altitude becomes extremely important.
  • The early rule out diagnosis that the ultrasound can provide is very useful for managing flight plans
  • Weather was decided as a key factor that would alter management and it would impact possibly both medical decision making and flight operations
  • Placement of ultrasound in the machine: crewman/paramedic at the head of patient holding the machine with doctor on the patient’s right side
A little in-situ training. Enabled us to figure out optimal ergonomics and positioning for in-flight ultrasound. In case you're wondering, I donated my chest to science for this ultrasound to be done

A little in-situ training. Enabled us to figure out optimal ergonomics and positioning for in-flight ultrasound.
In case you’re wondering, I donated my chest for this ultrasound to be done (free of charge!)

Summary

  • Overall based on our evaluations of the process, it was a successful event with more case-based learning sessions planned
  • Clinicians reluctant to intervene for pre-hospital pneumothorax unless unstable
  • Strong communication among the team about the presence of a pneumothorax is essential and ultrasound greatly aids with this – affects both medical & operational decision making
  • Ergonomics are important but dependent on each setting; however a standard approach in the machine might be appropriate for positioning of the ultrasound

 

New clinical simulation lab at ARHT and our newest team member!

Over the past few months at ARHT, we’ve been working to secure a location that can be used as our clinical sim lab. While most of our sim is done outside, this will allow for a “think tank” and location to keep all of our supplies. A spot like this will have a huge positive impact on improving our ability to run effective in-situ simulation.

Rossi, our Emergency Medicine award winning medical student (and newest team member) While it may not be the exact replica of the EM award...it's pretty close!

Rossi, our Emergency Medicine award winning medical student (and newest team member) While it may not be the exact replica of the EM award…it’s pretty close!

In addition, we plan to use this site for task training and trialling new equipment. While it has taken some time to get it organized, we’ve made huge progress recently. One of the main reasons we’ve had such success can be attributed to our newest education team member, Rossi, who is a senior medical student at the University of Auckland. She has a keen interest in emergency medicine, retrieval medicine and trauma. Her enthusiasm has been crucial to getting us up and running with a fully functional sim lab. We should also acknowledge her recent achievement as the recipient of a special mention in Emergency Medicine for dedication & teamwork at U of Auckland Medical school. Welcome Rossi, and we look forward to all that you bring!

I also felt it would be great to show the progress we’ve made with the sim lab. This will be an outstanding location to think, work and practice. We’ll be able to re-pack packs for simulations and engage in task training modules.

Here’s a few pics of the progress…and completion!

Sim lab: the beginning

Sim lab: the beginning

Rossi doing her best Vanna White impersonation

Rossi doing her best Vanna White impersonation

Sim Lab: the current state! Ready for use!

Sim Lab: the current state! Ready for use!

Sim Lab: airway task trainers...clearly needing a cric to be performed!

Sim Lab: airway task trainers…clearly needing a cric to be performed!

Prehospital Management of Traumatic Brain Injury

extradural-haematoma

To date, the most significant procedural capability the the addition of doctors to the ARHT Westpac Rescue Helicopter has provided has been RSI capability. Of the RSIs performed so far,  a significant proportion have been for severe traumatic brain injury (TBI).

With the exception of surgical intervention (which is required in a minority of cases of severe TBI), most other essential elements of severe TBI management can be provided in the prehospital setting – airway protection, optimisation of oxygenation, prevention of hyper- or hypo-carbia, support of cerebral perfusion pressure, and ICP control.

This paper, published in the Journal of Neurosurgery in 2008, reviews the evidence around the various elements of the pre-hospital severe TBI care ‘package’.

Take-home messages:

  • a period of hypoxia (PaO2<60mmHg) is associated with a 50% mortality rate and a 50% severe disability among survivors
  • in previous studies hypoxia has been a common complication of prehospital intubation for severe TBI, with up to 57% of patients experiencing transient hypoxia lasting a mean of 2.3 minutes (note – these studies frequently involved neither an RSI as we know it nor personnel who were appropriately trained and qualified; more recent evidence points to a benefit for prehospital RSI for severe TBI provided it is done well by appropriate people)
  • Tight control of CO2 after intubation has a significant effect on survival – in one large series patients with normal CO2 on arrival to ED had a 21% mortality, those with CO2 outside the normal range had a 34% mortality
  • Manual ventilation is associated with hypocarbia
  • A single episode of hypotension (systolic BP less than 90mmHG) doubles mortality
  • Management of hypotension in the field improves outcome
  • Transport by helicopter for patients with severe TBI improves odds of survival compared with ground transport (OR 1.6-2.25) – this may reflect the presence of more skilled personnel on the helicopter, careful attention to post-intubation ventilatory parameters, and transport to a trauma centre.