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20/07/2015

Dossier sauvetage au combat

 Dossier "Sauvetage au combat"

couv-4-2014.jpg

| Tags : sauvetage

11/07/2015

ATLS: Une vision archaïque ?

ATLS: Archaic Trauma Life Support?

Wiles MD Anaesthesia 2015, 70, 893–906

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Un éditorial décoifffant mais pas tant que cela. Une revue cochrane récente ne trouvait pas d'argument en faveur de l'intérêt de l'ATLS (1). Le bien fondé de ce type de fromation est très débattue dans les pays disposant d'une structure spécialisée de prise en charge de traumatisé( 2). Peu étonnant quand on connait l'histoire de l'ATLS censé apporter des connaissances et une méthode à des personnels et des structures hospitalières non spécialisées en traumatologie. Les conclusions de cet éditorial repositionne très bien ce type de formations courtes

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No one could have imagined that when a light aircraft crashed in rural Nebraska in 1976, the nature of global trauma management would be forever altered. James Styner, an orthopaedic surgeon, was piloting the plane in question and the accident resulted in the death of his wife and serious injuries to himself and his four children. The standard of care that he and his family received in the local hospital in the aftermath of the crash so horrified Styner that he decided to establish a new system for the management of major trauma...........................

Archaic ATLS.jpg

......So what direction should trauma training take in the future?

I would suggest the following:

1 Treat ATLS as a ‘basic’ trauma course, with attendance limited to junior medical staff with no trauma experience. Candidates will learn the common language and vocabulary of trauma management, which will be of benefit when they subsequently attend trauma calls in clinical practice. In the developing world, where resources and personnel are  limited, ATLS will continue to have a role.

2 Stop routine recertification of ATLS for individuals experienced in trauma management. Given the high cost of these courses (~£600 (€825; $918) for certification and £350 (€482; $535) for recertification) this practice will account for a significant proportion of an individual’s annual study leave budget. This time and money would be better invested in developing enhanced leadership, communication and teamworking skills.

3 In line with the Royal College of Anaesthetists, remove ATLS certification as a prerequisite for the completion of training in surgery and emergency medicine. Instead, focus on ensuring adequate experience in the management of major trauma.

4 Similarly, for consultant posts that include trauma management, remove ATLS certification as an appointment criterion.

Evidence of experience in trauma management, alongside formal training in leadership and/or human factors, would be of greater relevance.

5 Require regular team-training sessions for MTC staff, either by video review or utilising simulation, ideally within the team’s usual working environment. This would allow training to be institution-specific, with the potential to refine protocols and undertake focused debriefs of recent cases.

When introduced almost 40 years ago, ATLS represented the cutting edge of trauma management; unfortunately, the course has failed to evolve at a pace that allows it to be relevant to the care delivered in modern MTCs. This course without doubt revolutionised trauma care, but it should now be reserved for use in isolated rural centres or environments where trauma is managed infrequently and with limited resources. The King is dead, long live the King.

03/07/2015

Fibrinogène avec le TXA ?: Plutôt oui

Association of Cryoprecipitate and Tranexamic Acid With Improved Survival Following Wartime Injury: Findings From the MATTERs II Study

Morrison JJ et Al. JAMA Surg. 2013;148(3):218-225.

 

Objective To quantify the impact of fibrinogen-containing cryoprecipitate in addition to the antifibrinolytic tranexamic acid on survival in combat injured.

Design Retrospective observational study comparing the mortality of 4 groups: tranexamic acid only, cryoprecipitate only, tranexamic acid and cryoprecipitate, and neither tranexamic acid nor cryoprecipitate. To balance comparisons, propensity scores were developed and added as covariates to logistic regression models predicting mortality.

Setting A Role 3 Combat Surgical Hospital in southern Afghanistan.

Patients A total of 1332 patients were identified from prospectively collected UK and US trauma registries who required 1 U or more of packed red blood cells and composed the following groups: tranexamic acid (n = 148), cryoprecipitate (n = 168), tranexamic acid/cryoprecipitate (n = 258), and no tranexamic acid/cryoprecipitate (n = 758).

Main Outcome Measure In-hospital mortality.

Results Injury Severity Scores were highest in the cryoprecipitate (mean [SD], 28.3 [15.7]) and tranexamic acid/cryoprecipitate (mean [SD], 26 [14.9]) groups compared with the tranexamic acid (mean [SD], 23.0 [19.2]) and no tranexamic acid/cryoprecipitate (mean [SD], 21.2 [18.5]) (P < .001) groups. Despite greater Injury Severity Scores and packed red blood cell requirements, mortality was lowest in the tranexamic acid/cryoprecipitate (11.6%) and tranexamic acid (18.2%) groups compared with the cryoprecipitate (21.4%) and no tranexamic acid/cryoprecipitate (23.6%) groups. Tranexamic acid and cryoprecipitate were independently associated with a similarly reduced mortality (odds ratio, 0.61; 95% CI, 0.42-0.89; P = .01 and odds ratio, 0.61; 95% CI, 0.40-0.94; P = .02, respectively). The combined tranexamic acid and cryoprecipitate effect vs neither in a synergy model had an odds ratio of 0.34 (95% CI, 0.20-0.58; P < .001), reflecting nonsignificant interaction (P = .21).

Conclusions Cryoprecipitate may independently add to the survival benefit of tranexamic acid in the seriously injured requiring transfusion. Additional study is necessary to define the role of fibrinogen in resuscitation from hemorrhagic shock.

 

| Tags : coagulopathie

21/06/2015

Military Trauma System: Pour le civil ?

Military trauma system in Afghanistan: lessons for civil systems?

Bailey JA et Al. Curr Opin Crit Care. 2013 Dec;19(6):569-77

 

PURPOSE OF REVIEW:

This review focuses on development and maturation of the tactical evacuation and en route care capabilities of the military trauma system in Afghanistan and discusses hard-learned lessons that may have enduring relevance to civilian trauma systems.

 RECENT FINDINGS: 

Implementation of an evidence-based, data-driven performance improvement programme in the tactical evacuation and en route care elements of the military trauma system in Afghanistan has delivered measured improvements in casualty care outcomes.

MilitaryCivilian.jpg

 

SUMMARY: 

Transfer of the lessons learned in the military trauma system operating in Afghanistan to civilian trauma systems with a comparable burden of prolonged evacuation times may be realized in improved patient outcomes in these systems.  

Un nouveau concept de triage ?

Medical evacuation and triage of combat casualties in Helmand Province, Afghanistan: October 2010-April 2011

Clarke JE et Al. Mil Med. 2012 Nov;177(11):1261-6

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Un article de synthèse sur l'organisation de la chaîne de prise en charge des blessés par nos confrères anglais, avec notamment l'emploi d'une évolution majeure pour le un système anglo-saxon (lire ce document): le recours à des EVASAN médicalisées par des personnels ayant une pratique régulière de la prise en charge de patients en état critique. Cet article est intéressant car il insiste sur l'importance du triage et le rôe prééminent que peuvent jouer les role 2 notamment si les élongations sont importantes.

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Medical evacuation of combat casualties in Operation Enduring Freedom-Afghanistan is achieved primarily by helicopter, because of distances involved as well as ground-based threats. In Helmand Province, evacuation from the point of injury may occur on a variety of helicopter evacuation platforms with disparate levels of attendant medical expertise. Furthermore, triage to a medical treatment facility may involve varying echelons of care before definitive management. Consequently, considerable differences in medical care may be encountered between point of injury and definitive treatment. We discuss the role of helicopter-based medical evacuation in Helmand, Afghanistan, as well as triage and timelines to the most appropriate medical facilities. Based on our experience and available evidence, we have made recommendations to regional commanders which favor the utilization of prehospital critical care teams aboard helicopter-based evacuation platforms and direct triage to the highest echelon of care available when feasible

| Tags : triage, medevac, evasan

06/06/2015

Prise en charge d'un blessé: Ce n'est pas le SAMU, ni la catastrophe

Tactical medicine: a joint forces field algorithm.

Waldman M et Al. Mil Med. 2014 Oct;179(10):1056-61

 

Incident.jpeg

20/03/2015

Guidelines for field management of combat related head trauma

 

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07/03/2015

Mise en place du TCCC: Le point 2014

 SavingLife.jpg

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| Tags : tccc

06/03/2015

Mise en place du TCCC: Le point 2013

 

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| Tags : tccc

27/02/2015

Plaies par armes blanches

Elles ne sont pas très fréquentes dans notre contexte, le plus souvent accidentelles ou secondaires à des rixes entre villageois.

PlaieArmeBlanche.jpg

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23/02/2015

Pneumo suffocant: Oui

 

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Pneumothorax compressif, sous tension, tamponnade gazeuse. Autant de termes utilisés pour cette situation clinique à laquelle est souvent associé l'existence d'une hypotension artérielle, en fait surtout présente chez les patients ventilés. La détresse respiratoire est souvent au premier plan che le blessé non ventilé et le terme de pneumothorax suffocant adapté. Le document proposé est un peu ancien mais apporte une vision relativement didactique de la problématique séméiologique et physiopathologique.

| Tags : pneumothorax

13/01/2015

Attentats: Importance du garrot

The Initial Response to the Boston Marathon Bombing. Lessons Learned to Prepare for the Next Disaster 

Gates JD et AL. Ann Surg. 2014 Dec;260(6):960-6

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Le concept du garrot tactique est familier aux équipes militaires. L'expérience rapportée montre que ce concept doit également le devenir dans le monde de la médecine préhospitalière. 26 soit près de 10% blessés pris en charge ont fait l'objet d'une pose de garrot. Ainsi en cas d'attentat la pose précoce d'un garrot en cas d'hémorragie des membres est elle une mesure fondamentale de mise en condition de survie.

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OBJECTIVE:

We discuss the strengths of the medical response to the Boston Marathon bombings that led to the excellent outcomes. Potential shortcomings were recognized, and lessons learned will provide a foundation for further improvements applicable to all institutions.

BACKGROUND:

Multiple casualty incidents from natural or man-made incidents remain a constant global threat. Adequate preparation and the appropriate alignment of resources with immediate needs remain the key to optimal outcomes.

METHODS:

A collaborative effort among Boston's trauma centers (2 level I adult, 3 combined level I adult/pediatric, 1 freestanding level I pediatric) examined the details and outcomes of the initial response. Each center entered its respective data into a central database (REDCap), and the data were analyzed to determine various prehospital and early in-hospital clinical and logistical parameters that collectively define the citywide medical response to the terrorist attack.

RESULTS:

A total of 281 people were injured, and 127 patients received care at the participating trauma centers on that day. There were 3 (1%) immediate fatalities at the scene and no in-hospital mortality. A majority of the patients admitted (66.6%) suffered lower extremity soft tissue and bony injuries, and 31 had evidence for exsanguinating hemorrhage, with field tourniquets in place in 26 patients. Of the 75 patients admitted, 54 underwent urgent surgical intervention and 12 (22%) underwent amputation of a lower extremity.

Tourniquet Boston.jpg

CONCLUSIONS:

Adequate preparation, rapid logistical response, short transport times, immediate access to operating rooms, methodical multidisciplinary care delivery, and good fortune contributed to excellent outcomes.

12/12/2014

HEA: Possible pour les trauma ouverts

Differences between blunt and penetrating trauma after resuscitation with hydroxyethyl starch

Casey JA et Al. J Trauma Acute Care Surg. 2014;77: 859-864

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Ce travail effectué avec un HEA ancien (450/07: Hetastarch®, Hextent®) suggère que l'emploi des HEA lors de la prise en charge de trauma ouvert n'est pas associé à un risque accru de décès ou d'insuffisance rénale. On rappelle qu'il ne s'agit pas de la même classe d'HEA que celle que nous avons l'habitude d'utiliser (130/0.4: Voluven)

remplissage----------------------------------------------------------------

BACKGROUND: The purpose of this study was to test the hypothesis that a single bolus of 6% hydroxyethyl starch (HES 450/0.7 in lactated electrolyte injection) during initial resuscitation has a differential effect in blunt and penetrating trauma patients.
METHODS: Consecutive admissions to the trauma service were reviewed. Patients who died within 24 hours were excluded. Multivariate analysis defined individual predictors for the primary outcomes, acute kidney injury (AKI) and mortality within 90 days. Data were expressed as mean T SD, and significance was assessed at p G 0.05.
RESULTS: Therewere 1,410 patients (76% male; mean T SD, age 43 T 18 years; 68% blunt trauma; mean T SD Injury Severity Score [ISS] 14 T 11; AKI, 4.4%; and mortality, 3.4%). HES (0.5-1.5 L) was administered to 216 patients (15.3%). After multiple logistic regression, HES remained a significant independent predictor of AKI after blunt trauma (odds ratio [OR], 2.54; 95% confidence interval [CI], 1.24-5.19; area under the receiver operating characteristic curve [AUROC], 0.809) but not penetrating
trauma (OR, 0.90; 95% CI, 0.23-3.60; AUROC, 0.849). In separate logistic regression models, HES was a significant predictor of mortality after blunt trauma (OR, 3.77; 95% CI, 0.91-0.97; AUROC, 0.921) but not penetrating trauma (OR, 0.72; 95% CI, 0.13-3.94; AUROC, 0.904).

HES.jpg
CONCLUSION: HES is an independent risk factor for AKI and death after blunt, but not penetrating, trauma, which underscores a fundamental difference between these two injury types.

| Tags : remplissage

Prehospital management of chest injuries

The prehospital management of chest injuries: a consensus statement. Faculty of Pre-hospital Care, Royal College of Surgeons of Edinburgh

Lee C. et AL. Emerg Med J 2007;24:220–224

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Un document un peu ancien des nos confrères britanniques mais qui reste d'actualité.

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This paper provides a guideline for the management of prehospital chest injuries after a consensus meeting held by the

Faculty of Prehospital Care, Royal College of Surgeons of Edinburgh, Edinburgh, UK, in January 2005. An overview of

the prehospital assessment, diagnosis and interventions for life threatening chest injury are discussed, with the application of

skills depending on the training, experience and competence of the individual practitioner

| Tags : thorax

30/11/2014

ATLS ? Peut être mais pas pour les seniors !

Training to Manage Ballistic Trauma

Boffard KG et Al. in  Ballistic Trauma A Practical Guide 

La prise en charge d'un polytraumatisé nécessite une approche très structurée et coordonnée qui fait intervenir de multiples professionnels de la médecine d'urgence. L'ATLS est un cours qui fait référence en matière de traumatologie notamment dans les pays anglo-saxons. Son apport réel est discuté notamment dans les pays qui bénéficie d'un environnement hospitalier conséquent (1, 2). L'intérêt réel de cette formation est en train de se repositionner notamment du fait de nouveaux concepts de prise en charge et l'apparition des formation en équipe par simulation en mode immersif. Le document proposé fait le point sur les démarches actuelles de formation à un tel type de prise en charge. Il présente l'ATLS comme une formation plutôt destinée aux plus jeunes, l'expertise nécessaire tant individuelle que collective devant faire appel des des enseignements beaucoup plus conséquents. 

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Soutien médical des interventions à risque

Tactical Medicine: A Joint Forces Field Algorithm

Waldman M et Al. Military Medicine, 179, 10:1056, 2014

Les forces de l'ordre interviennent de plus en plus dans un contexte de violence extrême qui impose la planification du soutien médical de ces opérations selon des principes militaires. Une telle approche est fait par les équipes israélienne. Le document proposé détaille l'algorithme proposé ci dessous. 

Incident.jpeg

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17/11/2014

Pneumothorax et vol en altitude : Possible ?

Cleared for takeoff: The effects of hypobaric conditions on traumatic pneumothoraces

Majercik S. et All. J Trauma Acute Care Surg. 2014;77: 729-733

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La présence d'un pneumothorax traumatique non résolu ne serait pas (ou plus ) une contre-indication à un voyage aérien. C'est ce que suggère ce travail
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BACKGROUND: Current guidelines suggest that traumatic pneumothorax (tPTX) is a contraindication to commercial airline travel, and patients should wait at least 2 weeks after radiographic resolution of tPTX to fly. This recommendation is not based on prospective, physiologic study. We hypothesized that despite having a radiographic increase in pneumothorax size while at simulated altitude, patients with a recently treated tPTX would not exhibit any adverse physiologic changes and would not report any symptoms of cardiorespiratory compromise.

 

METHODS: This is a prospective, observational study of 20 patients (10 in Phase 1, 10 in Phase 2) with tPTX that has been treated by chest tube (CT) or high flow oxygen therapy. CT must have been removed within 48 hours of entering the study. Subjects were exposed to 2 hours of hypobaria (554 mm Hg in Phase 1, 471 mm Hg in Phase 2) in a chamber in Salt Lake City, Utah. Vital signs and subjective symptoms were recorded during the ‘‘flight.’’ After 2 hours, while still at simulated altitude, a portable chest radiograph (CXR) was obtained. tPTX sizes on preflight, inflight, and postflight CXR were compared.

 

RESULTS: Sixteen subjects (80%) were male. Mean (SD) age and ISS were 49 (5) years and 10.5 (4.6), respectively. Fourteen (70%) had a CT to treat tPTX, which had been removed 19 hours (range, 4Y43 hours) before the study. No subject complained of any cardiorespiratory symptoms while at altitude. Radiographic increase in tPTX size at altitude was 5.6 (0.61) mm from preflight CXR. No subject developed a tension tPTX. No subject required procedural intervention during the flight. Four hours after the study, all tPTX had returned to baseline size.

 

CONCLUSION: Patients with recently treated tPTX have a small increase in the size of tPTX when subjected to simulated altitude. This is clinically well tolerated. Current prohibitions regarding air travel following traumatic tPTX should be reconsidered and further studied.

 

| Tags : pneumothorax

12/06/2014

Traumatisé de guerre: Cela évolue

Systematic review of the prevalence and characteristics of battle casualties from NATO coalition forces in Iraq and Afghanistan

Hoencamp R. et All. Injury, Int. J. Care Injured 45 (2014) 1028–1034

Background: The North Atlantic Treaty Organization (NATO) coalition forces remain heavily committed on combat operations overseas. Understanding the prevalence and characteristics of battlefield injury of coalition partners is vital to combat casualty care performance improvement. The aim of this systematic review was to evaluate the prevalence and characteristics of battle casualties from NATO coalition partners in Iraq and Afghanistan. The primary outcome was mechanism of injury and the secondary outcome anatomical distribution of wounds.
 
Methods: This systematic review was performed based on all cohort studies concerning prevalence and characteristics of battlefield injury of coalition forces from Iraq and Afghanistan up to December 20th 2013. Studies were rated on the level of evidence provided according to criteria by the Centre for Evidence Based Medicine in Oxford. The methodological quality of observational comparative studies was assessed by the modified Newcastle-Ottawa Scale.
 
Results: Eight published articles, encompassing a total of n = 19,750 battle casualties, were systematically analyzed to achieve a summated outcome. There was heterogeneity among the included studies and there were major differences in inclusion and exclusion criteria regarding the target population among the included trials, introducing bias. The overall distribution in mechanism of injury was 18% gunshot wounds, 72% explosions and other 10%. The overall anatomical distribution of wounds was head and neck 31%, truncal 27%, extremity 39% and other 3%.
 

Battlefield .jpg

 
Conclusions: The mechanism of injury and anatomical distribution of wounds observed in the published
articles by NATO coalition partners regarding Iraq and Afghanistan differ from previous campaigns. There was a significant increase in the use of explosive mechanisms and a significant increase in the head and neck region compared with previous wars.

13/05/2014

Lésions rachidiennes: Plus fréquentes qu'envisagé

Spinal Injuries in United States Military Personnel Deployed to Iraq and Afghanistan

An Epidemiological Investigation Involving 7877 Combat Casualties From 2005 to 2009

Schoenfeld AJ et All. Spine 2013;38:1770–1778

Les lésions du rachis sont plus fréquentes que ce qui était supposé. Ce travail rapporte qu'une atteinte du rachis est présente dans 11% des cas. Une des explications est que l'amélioration des conditions de prise en charge permet la survie de blessés plus graves qu'auparavant, qui autrefois ne survivait pas à leurs blessures.

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In the years 2005 to 2009, 872 (11.1%) casualties with spine injuries were identified among a total of 7877 combat wounded. The mean age of spine casualties was 26.6 years. Spine fractures were the most common injury morphology, comprising 83% of all spinal wounds. The incidence of combat-related spinal trauma was 4.4 per 10,000, whereas that of spine fractures was 4.0 per 10,000. Spinal cord injuries occurred at a rate of 4.0 per 100,000.

SpinalAFGIRAK2.jpg

Spinal cord injuries were most likely to occur in Afghanistan (incident rate ratio: 1.96; 95% confi dence interval: 1.68–2.28), among Army personnel (incident rate ratio: 16.85; 95% confidence interval: 8.39–33.84), and in the year 2007 (incident rate ratio: 1.90; 95% confi dence interval: 1.55–2.32). Spinal injuries from gunshot were significantly more likely to occur in Iraq (17%) than in Afghanistan (10%, P = 0.02).

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| Tags : rachis

10/02/2014

Inhalation de fumées: Héparine en aérosol ?

Inhaled Anticoagulation Regimens for the Treatment of Smoke Inhalation–Associated Acute Lung Injury: A Systematic Review*

Miller AC et Al. Crit Care Med 2014; 42:413–419

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L'inhalation de fumées est fréquentes lors de la prise en charge de victilmes par explosion. Laprise en charge de brNébiliser 5000 à 1000U d'héparine inhalé avec 3ml de NacétylCystéine et de l'albuterol améliorerait la survie 

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OBJECTIVE:

Inhaled anticoagulation regimens are increasingly being used to manage smoke inhalation-associated acute lung injury. We systematically reviewed published and unpublished preclinical and clinical trial data to elucidate the effects of these regimens on lung injury severity, airway obstruction, ventilation, oxygenation, pulmonary infections, bleeding complications, and survival.

DATA SOURCES:

PubMed, Scopus, EMBASE, and Web of Science were searched to identify relevant published studies. Relevant unpublished studies were identified by searching the Australian and New Zealand Clinical Trials Registry, World Health Organization International Clinical Trials Registry Platform, Cochrane Library, ClinicalTrials.gov, MINDCULL.com, Current Controlled Trials, and Google.

STUDY SELECTION:

Inclusion criteria were any preclinical or clinical study in which 1) animals or subjects experienced smoke inhalation exposure, 2) they were treated with nebulized or aerosolized anticoagulation regimens, including heparin, heparinoids, antithrombins, or fibrinolytics (e.g., tissue plasminogen activator), 3) a control and/or sham group was described for preclinical studies, and 4) a concurrent or historical control group described for clinical studies. Exclusion criteria were 1) the absence of a group treated with a nebulized or aerosolized anticoagulation regimen, 2) the absence of a control or sham group, and 3) case reports.

DATA EXTRACTION:

Ninety-nine potentially relevant references were identified. Twenty-seven references met inclusion criteria including 19 preclinical references reporting 18 studies and eight clinical references reporting five clinical studies.

DATA SYNTHESIS:

A systematic review of the literature is provided. Both clinical and methodological diversity precluded combining these studies in a meta-analysis.

CONCLUSIONS:

The high mortality associated with smoke inhalation-associated acute lung injury results from airway damage, mucosal dysfunction, neutrophil infiltration, airway coagulopathy with cast formation, ventilation-perfusion mismatching with shunt, and barotrauma. Inhaled anticoagulation regimens in both preclinical and clinical studies improve survival and decrease morbidity without altering systemic markers of clotting and anticoagulation. In some preclinical and clinical studies, inhaled anticoagulants were associated with a favorable effect on survival. This approach appears sufficiently promising to merit a well-designed prospective study to validate its use in patients with severe smoke inhalation-associated acute lung injury requiring mechanical ventilation.

SmokeInhalation.jpg

Depiction of airway changes in the setting of smoke inhalation–associated acute lung injury. Trachea and bronchi injury is characterized by mucosal hyperemia, increased microvascular permeability, exfoliation of the epithelial lining, mucous secretion, and an acute inflammatory cell influx (A–C) (57). As early as 1 hr postexposure, affected respiratory tract epithelium may display clumping, swelling, loss of cilia, blebbing, and surface erosion (B) (55). Within hours, sloughing of the respiratory mucosa progresses, a fibrinocellular pseudomembrane begins to form, and neutrophils begin to influx into the major airways (55). By 6 hr postinjury, the injured bronchi and bronchiole epithelium remains largely intact with focal areas of necrosis and sloughing (A, B) (56). Surface lining cells appear enlarged with cytoplasmic vacuolization, and neutrophils have begun to marginate and focally concentrate at points of epithelial necrosis (56). In addition, basal cells are normal in appearance, and the subepithelial connective tissue may appear slightly edematous with contained neutrophil infiltrates (56). By 24 hr, the ciliated and secretory lining cells are largely destroyed (C) (56). Cellular debris is admixed with fibroid material, mucus, and neutrophils creating a pseudomembranous fibrinocellular network that is adherent to both the cell-denuded basal lamina and the intact basal cells (C, D) (56). By 72 hr, injured epithelial areas are largely resurfaced by a stratified reparative epithelium with interposed areas of fibrinocellular exudate (D) (56). This epithelium is three to five cells thick, with flattened, nonciliated cells along the surface, and these cells are likely derived from proliferating and migrating basal cells (56). Subepithelial edema and inflammatory cell infiltrates begin to diminish (56). Complete repair of the respiratory tract epithelium with return of normal cilia populations may take up to 2–4 wk depending on the severity of smoke exposure.

| Tags : brûlure