Airway edema from burn injuries can progress rapidly, so securing the airway early when trouble is indicated is key. The clearest signal that an airway needs immediate protection is signs that the airway is becoming obstructed. If a patient exhibits stridor, significant hoarseness or voice changes, use of accessory muscles, or other signs of evolving obstruction, intubation should be performed promptly while the airway is still manageable. This proactive approach prevents a potential airway collapse and hypoxia that can occur if you wait for full obstruction to develop. While extensive facial burns or burns inside the mouth raise concern for possible airway swelling and necessitate careful monitoring and early planning, they do not by themselves prove that obstruction is present. A very large burn surface area indicates severity but does not directly indicate airway status. The key factor guiding early intubation is actual or imminent airway obstruction.

Adenosine is used in stable narrow complex tachycardia to transiently block AV nodal conduction and interrupt AV-nodal dependent reentrant circuits, delivering rapid, short-lived effects that help reveal or terminate the rhythm. Because it acts very quickly and has a short half-life, dosing starts low and is given as a rapid IV push with a saline flush to ensure it reaches the heart promptly. The standard starting dose is 6 mg, and this is the maximum for the first administration. If there’s no response after a short interval, a second dose of 12 mg can be given, and sometimes a third 12 mg dose may be used, but the initial dose remains 6 mg to balance effectiveness with safety.

When cyanide poisoning from smoke inhalation is suspected, hydroxocobalamin is given IV to bind cyanide quickly. The standard emergent dose is 5 g administered over about 15 minutes, providing rapid cyanide sequestration so tissues can resume oxygen use. Intravenous delivery ensures fast onset; administering by intramuscular route would delay absorption and delay treatment. The other dosing options are not appropriate because they are either far too small or not delivered in a way that achieves rapid, sufficient cyanide binding. A 5 g IV dose over 15 minutes is the widely accepted approach, with a second dose sometimes considered per local protocols if needed.

Death pronouncement in the field relies on postmortem changes that prove circulation and metabolism have ceased. The two conclusive signs are dependent lividity and rigor mortis. Dependent lividity is the pooling of blood in the lowest parts of the body after circulation stops, producing a characteristic purplish discoloration. Rigor mortis is the progressive stiffening of muscles due to chemical changes in the muscles after death, beginning a few hours after death and reaching full rigidity within hours. When both signs are present, they together confirm that death has occurred, since they reflect ongoing cessation of circulation and metabolic processes beyond reversible states. One sign alone is not definitive, and timing can vary with temperature and other factors, but the combination of dependent lividity and rigor mortis is the best indicator in the field.