OFF THE PRESS….”In case of a Fire, don’t freak out and run like hell!”
Dr Malcolm provides this great summary of burns management…
In this You’ll find plenty of key exam fodder:
Burns resuscitation
Fluid management
Tertiary Referral Criteria
And to keep you warm on this wonderful Summer’s day, a stylised Final FRCA SAQ:
A 23 year old woman is brought in to the Ed with sever dermal burns limited to her chest, face and hands. She is 60kg. Her GCS is 14.
- List the reasons a burns patient may require intubation and ventilation (20%)
- What difficulties may be encountered in routine monitoring of these patients? (10%)
- What are the referral criteria for a burns patient to a specialist burns centre? (15%)
- Describe the “Rule of nines” and Parkland formula. Estimate the fluid resuscitation required by this patient. (20%)
- List the complications which can result from severe burn injury (15%)
- What are the key principles of ICU (intensive care unit) management in a patient with severe burns? (15%)
Anaesthetic teaching 
1) Airway protection (due to upper airway swellings caused by superheated air), oxygenation management (lower airway damage could result in the disruption of alveolar integrity resulting in surfactant elimination and noncardiogenic pulmonary edema), ventilation management (lung protective strategies needed to prevent against possibility of a restrictive component).
2) Difficulties in monitoring patients with burn injuries include infection control, airway management, and pain control. Routine examinations become complicated due to burn exposure to bacteria and the possibility of nosocomial infections. The risk and benefits of invasive monitoring techniques/lines should be considered.
3) The American Burn Association identifies several factors that meet the criteria of specialty burn care: Partial thickness >10%; burns in face, hands, genitalia, feet, perineum, joints; third degree for any age; electrical, chemical, inhalation burns; comorbidities; co-injuries; pediatric patient; other special needs not provided at nearby or present facility.
4) Rule of Nines described regions of the body and their value in determining TBSA%. The parkland formula is used to determine fluid resuscitation amounts. 23 yo female with burns to chest, face, hands=18+9+1+1=29% (I use 1% for the patient’s hands; perhaps I should used 2% for anterior/posterior?). Parkland formula: 4 x 60 kg x 29 = 6960-7000 ml of fluid to be administered in the first 24 hours after insult.
5) From High to Low: airway collapse, cellular hypoxia (due to CO poisoning, metabolic acidosis, systemic inflammatory response, acute respiratory distress syndrome, multiple organ dysfunction syndrome, infection, electrolyte imbalance, to name a few….
6) Not sure what ITU is, but key principles in my head include (for a paramedic): initial scene size up and safety, removal of patient to safe arena, stopping any current burning process (remove burning clothes, tissue still burning, etc), treatment of any apnea or ventilatory insufficiency, high flow oxygen via NRB/BVM, cardiac and ETCO2 monitoring, thorough assessment of airway, lungs, and TBSA, calling for additional resources (helicopter), treatment of other injuries (spinal immobilization?), IV access and immediate fluid administration, pain management/sedation if necessary, prepare for intubation if necessary and rapid sequence intubation if airway compromise is a possibility.
LikeLike
I would also like to add that as a respiratory therapist, I have another set of principles surrounding mechanical ventilation. Since inhalation injuries and upper airway issues are a concern, my initial thought is of course airway protection with the possibility of emergency cricothyrotomy in rare cases (or emergency tracheostomy). My deep concerns with mechanical ventilation involve a lung protective strategy to prevent further ALI that may lead to ARDS. This of course includes low Tv (4-8 ml/kg) and PEEP therapy (as much as 15 cmH2O). Although I am no expert in respiratory management of burn victims, I would imagine that APRV and HFOV is definitely a great ventilatory strategy that will prevent such ALI. With conventional mechanical ventilation, I would definitely utilize ventilators that could provide autoflow should volume control be used. APRV would be a great tool to utilize early on in the management process, as well as pressure control even sooner.
LikeLike
Thanks dbritt0044, although the OSCAR and OSCILLATE trials published in the NEJM aren’t directly related to burns, patients with burns would have fit their inclusion criteria and the results didn’t show benefit in Oscar and Oscillate stopped early due to higher mortality in the HFOV group. Do you know of any large trials that might support it’s use in this group? Equally I would, having no experience of APRV, be very interested to know about any data to support its use? Presumably the benefit being reduced peak pressures thus reduction in barotrauma?? Thanks again. Interesting thoughts.
LikeLike
DrTBaker,
Thanks for the reply! I honestly couldn’t help but grin when you mentioned the OSCAR and OSCILLATE trials. As I am responding to you, I actually have them out right beside me. To be quite frank, I am actually a fan of APRV as opposed to HFOV. Much of any defense I have of HFOV comes from anecdotal and clinical experience given to me by instructors and mentors that are much more knowledgeable on the subject. However, I understand that this has little value when it comes to hard core evidence.
Let me just quickly comment on the OSCAR and OSCILLATE trials. We know that the OSCILLATE trial was associated with higher mortality than the OSCAR trial which showed equal benefit to conventional MV. Here are just some quick recaps on the studies that kind of put things in perspective for me:
From OSCILLATE: *In the patients that were classified in the intervention group (HFOV), 81% actually survived and were subsequently transitioned to conventional ventilation (222/275). However, there was actually a subgroup that transitioned from conventional ventilation to HFOV, and these individual experienced 71% mortality.
Here is a pretty well balanced website article that comments on these studies: http://www.medscape.com/viewarticle/782130
Of course, we must also remember that the patients receiving HFOV were placed on high levels of sedation, NMBAs, and vasopressors.
Now for APRV… I’m not sure what you’re background in APRV is, so just humor me and let me briefly describe it. Airway Pressure Release Ventilation is basically an inverse ratio. For adults, we’re talking >4 secs of inspiratory time with as little as 0.5 secs for expiration. The idea? Open lung ventilation, recruitment, decrease in atelectrauma. You mentioned barotrauma. I totally agree that APRV decreases peak pressures, but for me as a therapist, the real benefit from APRV and especially from HFOV is the decrease in atelectrauma (the microstrains on alveoli from the opening and closing during PPV). We both know that baro/atelect/volutrauma is was precipitates ARDS/MODS/SIRS/sepsis…. So by taking away that mechanism, we could potentially stop the process. APRV significantly increases mean airway pressure to improve oxygenation. Next time you got a pair of test lungs and a Servo I, check out how much the MAP increases from volume control to Bi-Vent (the trade name for Maquet).
In addition (and you can compare this to HFOV) APRV is showed to reduce the need for sedation and NMBAs (and we know how much is needed for HFOV).
A REALLY good review on APRV comes from Crit Care Med 2005 Vol 33 No 3: Other approaches to open-lung ventilation: Airway pressure release ventilation. By Nader M. Habashi, MD. DEFINITELY worth the read. A good quote from this article: “The mortality rates after the implementation of APRV in patients meeting criteria for ARDS were lower than reported in the ARDSNet trial, 21.4% vs. 31%. In addition, sedation requirements were reduced and NMBA use essentially eliminated from routine practice…”
In regards to burn/smoke inhalation patients, there seems to be some interesting evidence that supports the use of high frequency percussive ventilation: In the following study, patient groups who received HFPV experienced 28% mortality and those who received conventional had 43% mortality. (Use of high-frequency percussive ventilation in inhalation injuries. J Burn Care Res. 2007; 28(3):396-400 (ISSN: 1559-047X) Hall JJ; Hunt JL; Arnoldo BD; Purdue GF. Department of Surgery, Division of Trauma, Burns, and Critical Care, UT Southwestern Medical Center at Dallas, 5323 Harry Hines Boulevard, Dallas, Texas 75390-9158, USA.)
Here’s a really great review on APRV for the burn patient (coming from a respiratory therapy magazine!): http://www.rtmagazine.com/2007/02/aprv-for-the-burn-patient-population/
I apologize that I can’t provide more hard core literature or studies, especially for burn/smoke injury patients.
So take home points for me:
*Don’t be scared of PEEP
*HFOV is not dead, it’s still an option, but perhaps not first in line for treatment modalities
*Can the increased use of sedation and NMBA be the cause of mortality in these studies?
*When all else fails, HFOV has anecdotally been shown to save the day…
This seems to be a never ending battle between doctors and respiratory therapists. For me, the use of HFOV no longer needs evidence to show its benefit in neonatal population. We just have to find its role in adults and what the appropriate cointerventions are.
Great discussions though. Really jogs my brain!
(Besides our little “ICU round”, I hope my prehospital assessment and treatment was spot on!)
LikeLike
Thank you for your comments and for taking the time to answer the questions. Your prehospital assessment and treatment was indeed spot on.
LikeLike