PACT moduleEnviromental hazards

Intensive Care Training ProgramRadboud University Medical Centre Nijmegen

Content

• Infections

• Chemical warfare

• Burns

• Blast wounds

Anthrax

• Bacillus anthracis

• Aerobic, gram-positive spore-forming rod

• Found in soil with infection most commonly in herbivore mammals

• Human contact with contaminated animal products

Anthrax

Clinical infection

• Cutaneous (most frequent)

• Gastrointestinal

• Inhalational (pulmonary)

• Injectional (drug use)

Anthrax - pathogenesis

• Presence of a capsule

• Production of 2 exotoxins (lethal factor - inactivates MAPKK & edema factor - increases intracellular cAMP)

• High microbial concentrations in infected hosts

Cutaneous anthrax

• 95% of reported anthrax cases

• Subcutaneous introduction of spores

• Painless pruritic papule 3 - 5 days following infection developing in characteristic black eschar

• With appropriate antibiotics death uncommon

Cutaneous anthrax

Gastro-intestinal anthrax

• Ingestion of poorly cooked meat

• Oral-pharyngeal (oral or esophageal ulcer with lymphadenopathy, edema and sepsis) or lower GI form (nausea, bloody diarrhea, acute abdomen, ascites and sepsis)

• High mortality (may approach 100%)

Gastro-intestinal anthrax

Inhalational anthrax

• Inhalation of small spores < 5 μm

• Two-stage illness (modal incubation time of 10 days) with flu-like symptoms followed by second fulminant stage with high fever, dyspnea, cyanosis, shock and sometimes hemorrhagic meningitis - very high mortality

• Mediastinal adenopathy and hemorrhagic pleural effusions

Inhalational anthrax

Injectional anthrax

• Mostly after subcutaneous heroin injection

• Tissue swelling and soft tissue infection 1 - 10 days after injection - no black eschar

• Surgical debridement and fasciotomy often necessary

• Intermediate mortality

Injectional anthrax

Diagnosis

• Gram stain and culture from blood and different sites

• Real-time PCR

Treatment (CDC)

• Ciprofloxacin (2 dd 400 mg/iv) + Pen G (6 dd 4 × 106 U) + Clindamycin (3 dd 600 mg) for severe disease (60 days)

• Ciprofloxacin alone for cutaneous form

• Anti-toxin therapies still experimental

• Pleural fluid drainage with inhalational form

Hicks CW. Intensive Care Med 2012;38:1092-1104

Brandwonden - EMSB

• Eerste opvang (buiten ziekenhuis)

• Koelen door spoelen (10 min) met lauw stromend water

• Bij chemische brandwonden 45 minuten

• Koelingsdeken voor transport controversieel

• Ainhalatie-BCO/Cyanide-C-D-Ewarme omgeving

• Infuus vanaf 15% (kinderen 10%) TVLO

• 4 ml/kg/%TVLO per 24 uur waarvan de helft in 1ste 8 uur van af moment van verbranding

Wanneer naar brandwonden centrum?• > 10% TVLO (> 5% bij kinderen)

• > 5% 3de graads verbranding

• Bejaarden en kinderen

• In combinatie met ander trauma/inhalatie

• Verbranding functionele gebieden

• Electriciteit en chemische verbranding

Halfzittend

Beoordeling brandwond

• Uitgebreidheid

• Regel van 9 ( bij kinderen relatief groter hoofd)

• Lund en Browder Chart

• Eerste graad telt niet mee

Lund en BrowderVerbranding 1 jaar 1-4 jaar 5-9 jaar 10-14 jaar 15 jaar

Hoofd 19 17 13 11 9

Hals 2 2 2 2 2

Romp voor 13 13 13 13 13

Romp achter 13 13 13 13 13

Rechter bil 2.5 2.5 2.5 2.5 2.5

Linker bil 2.5 2.5 2.5 2.5 2.5

Genitaliën 1 1 1 1 1

Rechter bovenarm 4 4 4 4 4

Linker bovenarm 4 4 4 4 4

Rechter onderarm 3 3 3 3 3

Linker onderarm 3 3 3 3 3

Rechter hand 2.5 2.5 2.5 2.5 2.5

Linker hand 2.5 2.5 2.5 2.5 2.5

Rechter bovenbeen 5.5 5.5 5.5 5.5 5.5

Linker bovenbeen 5.5 5.5 5.5 5.5 5.5

Rechter onderbeen 5 5 5 5 5

Linker onderbeen 5 5 5 5 5

Rechter voet 3.5 3.5 3.5 3.5 3.5

Linker voet 3.5 3.5 3.5 3.5 3.5

Beoordeling brandwond

• Diepte

• Dynamisch proces

• 1ste graad - alleen epidermis (niet meetellen)

• 2de graad - dermis (glanzend, blaren, pijn, CR+)

• 3de graad - subcutis ( blaren kapot, CR-, geen pijn, dof)

• 4de graad - vaak verkoling

1ste graad

2de graad

3de graad

Inhalatie trauma

• Sterke toename morbiditeit en mortaliteit

• Indicatie overplaatsing centrum

• Bronchoscopie essentieel voor diagnose en vaststellen uitgebreidheid

• Hittetrauma mondkeelholte, chemische tracheobronchitis, CO/cyanide

Therapie

• Vroege intubatie

• Dagelijks bronchoscopie/lavage

Initiële resuscitatie

• Vocht toediening is essentieel maar gebruik geen rigide schema’s

• toename glottis oedeem

• ischemie bij circulaire verbrandingen

• abdominaal compartiment syndroom

• verdiepen van de brandwond

Initiële resuscitatie

• Bij ernstig inhalatietrauma neemt vochtbehoefte met 25% toe

• Vochtbehoefte neemt ook toe bij electriciteitsverbranding

• Oedeemvorming na 24 - 48 uur stop

• Herstel hierna colloïd osmotische druk

• Na 48 uur verdampingsverlies

• (25 + % TVLO) * lichaamsopp (m2) in ml/uur

Experimenteel

• Hoog gedoseerd vitamine C (< 2 uur na verbranding)

• Acetylcysteïne

Lichtenberg figuur

The explosion

3000 - 8000 m/s

Mechanisms

• Detonation resulting in shockwave

• Penetrating injury through bombfragments or material at the site of explosion

• Wind of the explosion - blunt trauma

• Burn wound (flash/clothes), inhalation, asphyxiation

85% of deadly injuries caused by shockwave

Explosion in closed space

• Higher mortality

• Higher ISS

• More damage through detonation

• More burn wounds

Detonation - blast wave

• Ear damage

➡ rupture tympanic membrane, dislocation and bleeding middle ear

• Intestinal damage

➡ contusion, intramural hematoma, perforation 0.1 - 1.2%, often delay between explosion and perforation, especially in colon

Detonation -blast wave

• Lungs

➡ 4.8 - 8.4%

➡ contusion, pneumothorax, lung bleeding, air embolus

➡ bilateral and diffuse with explosion in closed space

• CNS

➡ air embolus, diffuse axonal damage

Detonation - blast wave

• Trias of bradycardia/hypotension/hypoxia

➡ (vagal) pulmonary “defensive” reflex through C fibres in alveolar interstitium activated by acute pulmonary congestion (duration 1 - 2 hours)

Madrid• 243 victims

➡ 99 ruptured tympanic membranes

➡ 97 pulmonary trauma

➡ 89 bomb fragments

➡ 44 fractures

➡ 45 burn wounds

➡ 41 eye damage (rupture eye, retinitis)

➡ 12 abdominal damage

➡ 5 traumatic amputations

Tsokos M. Am J Respir Crit Care Med 2003;168:549-555

Tsokos M. Am J Respir Crit Care Med 2003;168:549-555

Tsokos M. Am J Respir Crit Care Med 2003;168:549-555

“Blast lung”

• Delay sometimes of 24 - 48 hours

• In closed space always < 6 hours

• Dyspnea, dry cough, hemorrhagic sputum and hemoptoe

• Lung protective ventilation ± preventive chest tube

Intensive Care

• Principes of ATLS + EGDT

• Damage control principles

• Standard intensive care treatment

• Intestinal perforation often after delay

• Unusual infections

➡ Candida, HIV, Hepatitis B

Inhalation trauma

• Especially in closed space

➡ Smoke

➡ Nitric oxides

➡ Phosgene

➡ Carbon monoxide

➡ Cyanide

➡ Heavy metals

Cyanide

• Cyanide often with CO after smoke inhalation

• Hypotension, coma and persistent acidosis despite adequate oxygenation

• Therapy with sodiumnitrite en thiosulfateHb Met

HbMetHb

CSodiumnitrite

C TCThiosulfate Hydroxycobalamine

5 gr

300 mg/iv

12.5 gr/iv

To remember

• Intestinal damage often after delay

• Lung damage most frequent cause of death in initial survivors

• Air embolus relatively frequent

• Remember toxic gasses

• Wounds often contaminated