Chapter 17: Burns Flashcards by P H

Burn: sunburn (epidermis)

First degree

How well did you know this?

Not at all

Perfectly

Burn: painful to touch; blebs and blisters; hair follicles intact; blanches (do not need skin grafts)

2nd degree burn: superficial dermis (papillary)

How well did you know this?

Not at all

Perfectly

Burn: decreased sensation; loss of hair follicles (need skin grafts

2nd degree burn: deep dermis (reticular)

How well did you know this?

Not at all

Perfectly

Burn: leathery (charred parchment); down to subcutaneous fat)

3rd degree burn

How well did you know this?

Not at all

Perfectly

Burn: down to bone; into adjacent adipose or muscle tissue

4th degree burn

How well did you know this?

Not at all

Perfectly

How do first and second degree burns heal?

By epithelialization (primarily from hair follicles)

How well did you know this?

Not at all

Perfectly

Can cause rhabdomyolysis with myoglobinuria - Tx: hydration, alkalinize urine

Extremely deep burns, electrical burns, or compartment syndrome

How well did you know this?

Not at all

Perfectly

Admission criteria for burns

2nd and 3rd degree burns: > 10% BSA in patients aged 50 years. > 20% BSA. To significant portions of hands, face, feet, genitalia, perineum or skin overlying major joints. - 3rd degree > 5% - Electrical and chemical - Concomitant inhalational injury, mechanical trauma, preexisting medical condition. - Injuries in patients with special social, emotional or long-term rehabilitation needs - Suspected child abuse or neglect

How well did you know this?

Not at all

Perfectly

MCC burns

Scald burns

How well did you know this?

Not at all

Perfectly

Burns: more likely to come to hospital and be admitted

Flamer burns

How well did you know this?

Not at all

Perfectly

Assessing percentage of body surface burned - Head - Arms - Chest - Back - Legs - Perineum

Head: 9 - Arms: 18 - Chest: 18 - Back: 18 - Legs: 36 - Perineum: 1

How well did you know this?

Not at all

Perfectly

When do you use Parkland’s formula?

Use for burns > 20% only

How well did you know this?

Not at all

Perfectly

What is the Parkland’s formula?

4cc/kg x % burn in first 24 hours, give 1/2 the volume in the first 8 hours

How well did you know this?

Not at all

Perfectly

What type of fluids should you use in burn resuscitation?

Lactated ringer’s solution (in the first 24 hours)

How well did you know this?

Not at all

Perfectly

Best measurement of resuscitation

Urine output - Adults: 0.5 - 1.0 cc/kg/hr - Children

How well did you know this?

Not at all

Perfectly

What are the disadvantages of the Parkland formula?

Can grossly underestimate volume requirements with inhalational injury, ETOH, electrical injury, post-escharotomy

How well did you know this?

Not at all

Perfectly

What can colloid (albumin) cause in first 24 hours of burn resuscitation?

Increased pulmonary / respiratory complications -> can use colloid after 24 hours

How well did you know this?

Not at all

Perfectly

Escharotomy indications (perform within 4-6 hours)

Circumferential deep burns - Low temperature, weak pulse, decreased capillary refill, decreased pain sensation, or decreased neurologic function in extremity - Problems ventilating patient with significant chest torso burns

How well did you know this?

Not at all

Perfectly

Risk factors for burn injuries

Alcohol or drug use, age (very young / very old), smoking, low socioeconomic status, violence, epilepsy

How well did you know this?

Not at all

Perfectly

What if compartment syndrome is suspected after escharotomy?

May need fasciotomy

How well did you know this?

Not at all

Perfectly

Accounts for 15% of burn injuries in children

Child abuse

How well did you know this?

Not at all

Perfectly

History and exam findings that suggest child abuse

History: delayed presentation for care, conflicting histories, previous injuries - Exam: sharply demarcated margins, uniform depth, absence of splash marks, stocking or glove patterns, flexor sparing, dorsal location on hands, very deep localized contact injury

How well did you know this?

Not at all

Perfectly

What primarily causes lung injury in burns?

Lung injury caused primarily by carbonaceous materials and smoke, not heat.

How well did you know this?

Not at all

Perfectly

Risk factors for airway injury in burns

ETOH, trauma, closed space, rapid combustion, extremes of age, delayed extrication

How well did you know this?

Not at all

Perfectly

Signs and symptoms of possible airway injury

Facial burns, wheezing, carbonaceous sputum

Indications ofr intubation after burn

Upper airway stridor or obstruction, worsening hypoxemia, massive volume resuscitation can worsen symtpoms

MC infection in patients with > 30% BSA burns

Pneumonia

MCC death after > 30% BSA burns

Pneumonia

Tx: acid and alkali burns

Copious water irrigation

Produce deep burns due to liquefaction necrosis

Alkali burns

Produce coagulation necrosis

Acid burns

Tx: hydrofluoric acid burns

Spread calcium on wound

Tx: powder burns

Wipe away before irrigation

Tx: tar burns

Cool, then wipe away with lipophilic solvent (adhesive remover)

rns: need cardiac monitoring

Electrical burns

Complications of electrical burns

Can cause rhabdomyolysis and compartment syndrome - Polyneuritis, quadriplegia, transverse myelitis, cataracts, liver necrosis, intestinal perforation, gallbladder perforation, pancreatic necrosis.

Cardiopulmonary arrest secondary to electrical paralysis of brainstem

Lightning

1st week: early excision of burned areas - Caloric Need

25 kcal/kg/day + (30 kcal x 30% burn)

1st week: early excision of burned areas - Protein need

1 g/kg/day + (3g x %burn)

Best source of nonprotein calories in patients with burns

Glucose - Burn wounds use glucose in an obligatory fashion

Excise burn wounds in > 72 hours (but not until after appropriate fluid resuscitation for)...

Used for deep for 2nd, 3rd, and some 4th degree burns

What is burn viability based on after excision?

Color, texture, punctate bleeding after removal.

When do you treat burn wounds to face, plans, soles and genitals?

Deferred for the first week

When are skin grafts contraindicated?

If culture is positive for beta-hemolytic strep or bacteria > 10^5.

Decreased infection, desiccation, protein loss, pain, water loss, heat loss, and RBC loss compared to dermal substitutes

Autografts (split-thickness [STSG] or full-thickness [FTSG])

What regenerates the donor skin site with autografts?

Donor skin site is regenerated from hair follicles and skin edges on STSGs

Vascularization of autografts - Days 0-3 - Day 3

- Days 0-3: Imbibition (osmotic) - Day 3: neovascularization

Sites: poorly vascularized beds are unlikely to support skin grafting

Includes tendon, bone without periosteum, XRT areas

Measurements of split-thickness grafts

12-15mm (includes epidermis and part of dermis

Not as good as autografts - Can be a good temporizing material; last two to four weeks

Homografts (allografts; cadaveric skin)

Vascularize and are eventually rejected at which time they must be replaced

Allografts (ex of Homografts)

Not as good as homografts; last 2 weeks; these do not revascularize

Xenografts (porcine)

Not as good as homografts or xenografts

Dermal substitutes

Reasons to delay autografting

Infection, not enough skin donor sites, patient septic or unstable, do not want to create any more donor sites with concomitant blood loss

Most common reason for skin graft loss

Seroma or hematoma formation under graft Need to apply pressure dressing (cotton balls) to the skin graft to prevent serum and hematoma buildup underneath the graft.

More likely to survive - Graft not as thick so easier for imbibition and subsequent revascularization to occur

Split thickness skin grafts (STSGs)

Have less wound contraction - Good for areas such as the palms and the backs of hands

Full thickness skin grafts (FTSGs)

How can you improve burn scar hypo pigmentation and irregularities?

Can be improved with dermabrasion thin split-thickness grafts.

Treatment 2nd to 5th week: - Face

Topical antibiotics for 1st week, FTSG for unhealed areas (ngnmeshed)

Treatment 2nd to 5th week: - Hands

Superficial: ROM exercises, splint in extension if too much edema - Deep: immobilize in extension for 7 days after skin graft (need FTSG), then physical therapy. May need wire fixation of joints if unstable or open

Treatment 2nd to 5th week: - Palms

Try to preserve specialized palmar attachments. Splint hand in extension for 7 days after FTSG.

Treatment 2nd to 5th week: - Genitals

Can use STSG (meshed)

Is there a role for prophylactic antibiotics in burns?

MC organism in burn wound infections

Pseudomonas (followed by Staph, E. coli, enterobacter)

When are burn wound infections more likely to happen?

> 30% BSA

Have increased incidence secondary to topical antimicrobials

Candida infections

Impaired in burn patients (leaves them more susceptible to infection)

Granulocyte chemotaxis and cell-mediated immunity

Do not use in patients with sulfa allergy - Limited eschar penetration; can inhibit epithelialization - Ineffective against some Pseudomonas; effective for Candida

Silvadene (silver sulfadiazine)

Adverse effects: silvadene (silver sulfadiazine)

Can cause neutropenia and thrombocytopenia

Discoloration - Limited eschar penetration - Ineffective against Pseudomonas species and GPCs

Silver nitrate

Adverse effects: silver nitrate

Electrolyte imbalances (hyponatremia, hypochloremia, hypocalcemia, and hypokalemia) - Methemoglobinemia (contraindicated in patients with G6PD deficiency)

Can cause metabolic acidosis due to carbonic anhydrase inhibition (decreased renal conversion of H2CO3 -> H2O + CO2) - Good eschar penetration; good for burns overlying cartilage - Broadest spectrum against Pseudomonas and GNRs

Sulfamylon (mafenide sodium)

ADRs: sulfamylon (mafenide sodium)

Painful application - Can cause metabolic acidosis

Signs of burn wound infection

Peripheral edema, 2nd to 3rd degree burn conversion, hemorrhage into scar, erythema gangrenosum, green fat, black skin around wound, rapid eschar separation, focal discoloration

Organism: burn wound sepsis

Pseudomonas

MC viral infection in burn wounds

HSV

Best way to detect a burn wound infection (and differentiate from colonization)

Biopsy of burn wound

Complications after burns (x10)

Seizures, peripheral neuropathy, ectopia, corneal abrasion, symblepharon, heterotopic ossification of tendons, fractures, curling's ulcer, marjolin's ulcer, hypertrophic scar

Why seizures after burns?

Usually iatrogenic and related to sodium concentration

Why ectopia after burns?

From progressive contraction of burned adnexa (Tx: eyelid release)

How do you detect eye injury with burns?

Fluorescein staining to find injury (Tx: topical fluoroquinolone or gentamicin)

What is a symblepharon and treatment?

Eyelid stuck to conjunctiva. - Tx: release with glass rod

Tx: heterotopic ossification of tendons

Tx: physical therapy; may need surgery

How do you treat fractures with burn injury?

Tx: often need external fixation to allow for treatment of burns

Gastric ulcer that occurs with burns

Curling's ulcer

Highly malignant squamous cell CA that arises in chronic non-healing burn wounds or unstable scars

Marjolin's ulcer

Usually occur 3-4 months after injury seconds to increased neovascularity. - More likely to be deep thermal injuries that take > 3 weeks to heal, heal by contraction and epithelial spread, or heal across flexor surfaces - Tx?

Hypertrophic scar Tx: steroid injection into lesion (best), silicone, compression; wait 1-2 years before scar modification surgery

What is the mechanism of hypertrophic scars?

Usually occur 3-4 months after injury secondary to increased neovascularity

Do you use steroids in erythema multiforme and variants?

Erythema multiforme Stevens Johnson syndrome Toxic epidermal necrolysis

Erythema multiforme: least severe form (self-limited, target lesions) - Stevens Johnson syndrome: (more serious) -

What do you see in EM, SJS, and TEN?

Skin epidermal-dermal separation

What causes staph scalded skin syndrome?

Caused by staphylococcus aureus

Tx: EM / SJS / TEN

Fluid resuscitation and supportive; need to prevent wound desiccation with homografts / xenograft wraps; topical antibiotics, IV antibiotics if due to Staphylococcus

Drugs that cause EM / SJS / TEN

Dilantin, Bactrim, penicillin

Chapter 17: Burns Flashcards

(94 cards)