Burns Flashcards
Direct airway injury - pulmonary changes in burns
Causes direct tissue damage to upper airways by trying to absorb heat before reaching lower airways – tissue destruction & massive edema
Indirect airway injury - pulmonary changes in burns
Inhalation of noxious by-products (wood = CO, sulfur or nitrous = corrosive acids)
Circumferential burns
Create tourniquet effect - if on chest reduces chest compliance, FRC & mVe. May have to do escharotomy to area to prevent compartment syndrome
Initial cardiac changes (24-48 hours) in burns
Decreased CO - loss of volume, tourniquet effect like clamp on vena cava, endotoxins
Later cardiac changes (3-5 days) in burns
Increased CO from hypermetabolism- monitor UOP for adequate hydration!
Renal changes in burns
Decreased GFR - hypovolemia, myoglobinuria (electrical), hemoglobinuria – oliguria is sign of inadequate fluid resus.
Diuretics with burns
High voltage electrical burn, muscle burns or oliquria despite adequate CVP
Hepatic changes with burns
Hepatic injury from reduction in CO, absorbed toxins + drug toxicity, blood borne illnesses from multiple transfusions
Neurological changes with burns
Cerebral edema or increased ICP - HOB to 30, hyperventilate, maybe mannitol
Hematological changes with burns
Increased blood viscosity from fluid shifts - falsely elevated hgb/hct, thrombocytopenia initially, elevated platelet counts long term, if persistent hemolytic anemia – hematopoietic system adversely effected by burn, thrombocytopenia indicates sepsis
GI changes with burns
Ischemia from high levels of catecholamines, early enteral feeding to attenuate hypermetabolic response
Dobhoff placement for burns & anesthesia
Past duodenal sphincter - will not aspirate - leave TF going t/o surgery
TPN (hyperalimentation) and anesthesia
Don’t let it run out while in OR, check frequent sugars
Skin changes with burns
Not able to thermoregulate, maintain fluid & e-lytes & fight infection. 0.58 calories for every mL of evaporative water loss– children have greater BSA:wt ratio - effects magnified
Acute burns & albumin
Decreased circulating albumin = increase in plasma free fraction of drugs = more bang for your buck benzos & barbs
Acute burns & alpha-1 acid glycoproteins (A1AG)
Decrease in plasma free fraction of drugs - give very high doses of analgesics, locals, NDNMBAs
Half life of morphine with burns
Less than 1/3 the half life in similar child without burn
Succinylcholine & burns
Should not be given after 24 hours until 2 years post burn injury – hyperkalemia & cardiac arrest
ND-NMBAs & burns
Increased doses (2-5x more) - probably don’t use intubating dose unless you know you are going to have a really long surgery
Exogenous catecholamines & burns
Pay attention to epi/phenylephrine soaked gauze sponges placement & when they stop placing them… serious hypotension may happen if you aren’t paying attention
Stress ulcers & burns
High risk! prophylaxis with H2-receptor antagonist
First 24 hours of burn
Stabilization - ABC - protect airway early bc of edema especially if perioral burns and supplemental O2 to avoid CO poisoning. Circulation: large boer IV access with large amounts of fluid resuscitation 20 mL/kg/hr (avoid IV access in burn location when possible, and not below circumferential burns), maintain UOP 0.5 mL/kg/hr
Fluid mgmt of burns
Half the fluid calculated is delivered in first 8 hours, other half is next 16 hours, then maintenance
1st degree burn
Superficial, partial thickness
2nd degree brun
Superficial partial thickness (steam or scald, has blisters)
3rd degree burn
Full thickness, extension into SQ fat
4th degree burn
Full thickness involving deep tissues (even down to bone)
Intubations with burn patients
Subgloticc stenosis may start occurring due to multiple intubations, make sure to record tube size & cuff inflation so next person will know if they need to start with smaller tube
Tangential excision of burns
Layers of eschar shaved off until briskly bleeding tissue – rapid blood loss
Fascial excision of burns
Take all tissue including lymph & fat down to muscle fascia
Pre-determined stopping points in burn surgery
No greater than 15% BSA per surgical procedure,
Electrical burns mechanism & effects
Flow of current through resistant tissue generates heat, deep tissue injury likely (arterial, nervous system). All tx consider protection of renal fxn - will likely get severe myoglobinuria, hyperkalemia & ART - give copious IVF, osmotic/loop diuretics, alkalinize urine, dialysis.
