Morning Report: Inhalant Injuries

Thanks to Dr. Muhlfelder for today’s Morning Report!

Inhalant Injuries

Initial Mgmt: ABCs, IV, oxygen supplementation, monitor

Exam: bronchospasm, airway edema, nares +/- thermal injury

initial eval of airway is not good predictor of progressing edema/compromise, progresses over 24-72 hours
bronchopulmonary injury + cutaneous burns >30%BSA increases mortality to >70%

Common exposures/metal fumes: nitrogen oxides, cyanide, zinc, chlorine gas, ammonia, phosphorus, sulfur trioxides, Teflon

Immediate concern: reverse cellular asphyxia, CO and cyanide tox

Dispo:

Mild exposure: 4-6 hr observation, supplemental oxygen, nebulizers
Admission:
- closed-space exposure x 10 min+
- carbonaceous sputum production
- arterial p02 under 60mmHg
- metabolic acidosis
- COhgb >15%
- bronchospasm
- central facial burns

Indication for HBO:

CO tox w neuro abnml +LOC, profound acidosis, MI
CO>25%, or >15% in pregnancy (fetal hgb binds co more tightly)
Pulmonary edema

CO: causes tissue hypoxia by decreasing 02carrying capacity, hgb affinity x200 v 02, reduced 02 unloading, encephalopathy occurs 2/2 reperfusion injury w lipid peroxidation and free radical damage. Abnml exposure= >3%, >10% in smoker

CN: halts cellular respiration causing anaerobc metabolism and lactic acidosis

Zinc: decreased TLC, VC and CO diffusion leading to pulmonary edema, decreased compliance, increased airway resistance

Metal Fume Fever: fever, myalgias, headache, weakness, and nausea developing after 4-12 hrs s/p exposure. Self resolves within 2 days.

Complications: bronchiectasis, subglottic stenosis, PE, pneumonia, atelectasis, exacerbation of pre-existing respiratory dz (asthma, COPD)