Case 10 Burns Flashcards
1
Q
What are some sub layers of dermis?
A
- Thin papillary layer
Fibroblasts arrange in papillae/finger like projections –> produce collagen
Papillae contains blood vessels and nerve –> nerve sense pain and fine touch - Deeper reticular layer (thicker)
Fibroblasts produce collagen (packed tightly together) and elastin (inc flexibility)
Oil glands, sweat glands, hair follicles, lymphatics and nerves
Nerve sense pressure/vibration
2
Q
What makes up hypodermis?
A
- Made of fat and connect tissue
- Insulate and pads deeper tissue
- Anchor skin to muscles
3
Q
What are some causes of burns?
A
thermal
electrical
chemical
4
Q
What is thermal burns?
A
- UV light, flame, steam
- Remove all clothing and jewellery + running cold water for 20 min (NO ICE) + cover burn with clingwrap NOT circumferentially
5
Q
What is electrical burns?
A
- Power source (lightning or electrical), voltage (high or low)
- Electricity travels along path of least resistance –> nerve tissues, muscles, blood vessels are easier to travel than fat/bones
- Entrance and exit wound –> skin look fine
- Greater skin resistance (dry skin) –> local skin burn, lesser resistance (wet skin) –> deep tissue and systemic effects
- Muscle is injured, heart can be damaged, brain/spinal cord damage
6
Q
What is chemical burns?
A
- Acids: drain cleaners, coagulative necrosis caused by ischemia/infarction + denature proteins
- Bases: rust removers, swimming pool cleaners, in CEMENT, can penetrate deeper than acids –> liquefactive necrosis + cells dehydrate and collagen are denatured
- Redness/irritation, pain and numbness, formation of blisters of black dead skin at the site of contact, vision changes if gets into eyes, SOB, vomiting
- Wear protective gloves and glasses, cold running water
7
Q
What are different severity of burns and which skin layers do they affect?
A
1st degree burns/Superficial burns –> only epidermis
2nd degree burns –> epidermis and dermis
- superficial partial thickness burn –> only affect papillary layer of dermis
- deep partial thickness burn –> affect papillary and reticular layer BUT NOT the whole thickness
3rd degree/full thickness –> all thickness of epidermis and dermis
4th degree/deeper injury –> epidermis, dermis and hypodermis
8
Q
What does 1st degree burn look like?
A
- Red, dry, localised pain
- Wound blanching on pressure + rapid refill, erythema, no blisters
- Replaced with cells from stratum Basale without significant scarring
- Healing within 3-6 days
9
Q
What does 2nd degree burn look like?
A
Superficial partial thickness burn: only affect papillary layer of the dermis
- Wound blanching on pressure + slow refill, more painful
- Red and with clear blisters, wet/weeping
- Healing within 1 to 3 weeks
Deep partial thickness burn: affect reticular layer but not the whole thickness
- Vary in colour from yellow to white to red
- Damage to nerve and blood vessels –> no wound blanching on pressure + sluggish refill, minimal pain on apply pressure
- 3 weeks to a few months + scar
10
Q
What does 3rd degree burn look like?
A
- Waxy white to grey or black
- Wound blanching doesn’t occur, Elastin damage causes the burn to be stiff or inelastic
- Pain feels like deep pressure –> relatively painless due to nerve damage
- Burn does not heal by itself
11
Q
What does 4th degree burn look like?
A
- Charred black, dry, painless, significant oedema, numbness
- Patches of dead skin
- Minor healing at edges, often require skin grafting or possible amputation
12
Q
What are different zones of burns?
A
Zone of coagulation
- A central zone of irreversible, coagulative necrosis (due to ischemia)
Zone of stasis
- Surrounds the central zone and is comprised of damaged but viable tissue with decreased perfusion
Zone of hyperaemia
- savable with enough fluid resus
- Surrounds the zone of stasis and is characterised by inflammation and inc blood flow
13
Q
What are some complications of burns?
A
- Infections ESPECIALLY pseudomonas aeruginosa 4 days after burns most common cause of sepsis Staphylococcus aureus is the first pathogen to enter - Water loss Systemic complications - Haemodynamic instability --> SHOCK - Resp function - Hypovolaemia - Hypothermia - Hypermetabolic state - Major organ dysfunction such as kidneys - Infection sepsis
14
Q
What are different stages of healing?
A
- Reactive
Haemostasis and inflammation - Proliferative/repair
Granulation tissue
- Vascular granulation tissue –> network of newly formed capillaries, macrophages
- Fibrovascular granulation tissue –> proliferating fibroblasts, capillaries and macrophages
- Fibrous granulation tissue –> fibroblasts synthesise collagen and align themselves into uniform pattern - Maturing/remodelling
- Macrophages move into the tissue to remove dead cells
- Fibroblasts create new collagen to heal the damaged skin
Collagen accumulation
15
Q
What are some ways to measure burns?
A
Rule of nines (11 regions of body parts, each is 9% + 1% of groin region)
Lund and Browder chart
Palmar method
16
Q
What is the Rule of nine?
A
- First degree of burns is not calculated, ADULT ONLY
- CHILDREN: larger head and smaller limbs –> LUND AND BROWDER CHART + age of the child
- Not suitable for children or obese people
head front back --> 9% (front: 4.5%) chest: 9% back: 9% front abdomen: 9% back abdomen: 9% left arm: 9% (front: 4.5%) right arm: 9% (front: 4.5%) left and right leg front: 9% EACH left and right leg back: 9% EACH
17
Q
Why is lund browder chart more accurate?
A
- Age specific
- More accurate methods for both adults and children
18
Q
What is palmar method?
A
- Palmar surface of the patient’s hand
- Including palm and fingers
- 1% of TBSA
19
Q
What are some clinical symptoms of shock?
A
Hypotension, poor urine output, dyspnoea
20
Q
What are some symptoms for circumferential burns?
A
Circumferential burns around limbs
- Compartment syndrome
- Features of acute limb ischemia: weak/absent pulse, paraesthesia, pallor
Circumferential burns around abdomen
- Abdominal compartment syndrome: oliguria, acute pulmonary decompensation, hypoperfusion
- Signs of inc intraabdominal pressure: raised JVP, hypotension, tachycardia
21
Q
How do u determine different burns?
A
Is there epidermis (skin looking)?
YES –> epidermal burn
NO
Is it slippery/blisters?
YES –> thin blisters –> superficial dermal burn
NO
What is the burn colour?
RED –> deep dermal
WHITE –> full thickness
22
Q
What is management of minor burns?
A
1st and 2nd degree superficial thickness burns
Majority of superficial burn should heal in 10-12 days without complications
- Re-epithelisation as surviving keratinocytes in injured skin proliferate to restore the epidermal barrier
FACADE
First aid
- 20 min of cool running water, effective for 3 hours after injury
- Remove jewellery
- Elevate limbs to reduce oedema formation
Analgesia
- Choice of NSAIDs, paracetamol and opioids depending on the level of pain
Clean
- Wash with normal saline
- Remove debris, loose skin, blisters and shave hair
Assess
- Assess for depth should be painful and have brisk capillary refill
- Assess for moisture
Dress
- Guided by burn depth and amount of moisture in the burn
Elevate
- Elevate the affected area to minimise oedema
Follow up within 48-72 hours
23
Q
what are some criteria for burn unit referral?
A
- Greater than 10% total body surface area, > 5 % in children
- Special areas: face, hands, major joints, feet and genitalia, circumferential burns on limb and chest
- Full thickness burn > 5%, electrical and chemical burns
- Burns with inhalation injury
- Burns at extremes of age
- Burns associated with pre-existing illness
- Burns associated with major trauma
- Burn injury in pregnant women
- Non-accident burn
24
Q
What is primary survey and secondary survey in burn management?
A
Primary survey
- ABCDE
Secondary survey
- AMPLE
- type of burns
25
What is first aid for burn management?
- Remove all clothing and jewellery
- Running cold water for 20 min (NO ICE), acidic (20-30 min), alkaline (for hours)
- Cover burn with clingwrap and dry clean linen NOT circumferentially
- Keep patient warm to prevent hypothermia
- Cool the burned area with cool running water or saline-soaked gauze/wet towels
26
What is airway management?
- Introduce C spine protection
- Signs of inhalation injury
laryngoscope to look for oedema/obstruction of airway, oropharyngeal swelling, stridor and respiratory distress causing hypoxemia
Hoarseness of voice, facial burns, drooling, soot in the airway, singed nasal or facial hair --> secure airway prophylactically
- Endotracheal incubation is advisable early if signs of inhalation present
If airway is already closed --> consider surgical cricothyroidotomy
- Administer oxygen
- Carbon monoxide --> 100% oxygen using non-rebreather mask + check carboxyhemoglobin
27
What are some signs of airway injury
laryngoscope to look for oedema/obstruction of airway, oropharyngeal swelling, stridor and respiratory distress causing hypoxemia
Hoarseness of voice, facial burns, drooling, soot in the airway, singed nasal or facial hair, burns to face --> secure airway prophylactically
28
What is breathing management?
Administer oxygen
Adequacy of breathing when circumferential burns on chest wall and consider escharotomy
Baseline ABG and SaO2 > 95%, COHb poisoning
PaO2/FiO2 ratio is the ratio of arterial oxygen partial pressure (PaO2 in mmHg) to fractional inspired oxygen
200-300 --> mild ARDS
< 200 --> moderate
29
What is circulation management?
- burn assessment so fluid resus can be calculated
- Colour, capillary refill, HR, BP
- Burns > 15%/slow capillary refill should be given IV fluid based on Parkland formula
- Insert 2 large bore cannula
- If body temp is < 35 --> warm IV fluids + warm room can be given to prevent hypothermia
- Once got the percentage, insert into Parkland formula --> how much IV Ringer’s lactate (crystalloids has saline water with small molecules whereas colloids have big proteins that could build up in extracellular environments as cells broken down during burns, similar composition to extracellular fluids)
30
What is Parkland formula?
fluid for the first 24 hours post burn
%TBSA * KG * 4 = [] mL/24 hrs
half of calculated volume in first 8 hours FROM THE TIME OF BURN
i.e., if the burn is 3 hours ago, then give fluids in the remaining 5 hours
second half in next 16 hours
URINE OUTPUT TO ASSESS ADEQUACY
31
urine output monitor management
Urinary catheter -->Adequacy of fluid resus --> urine output hourly
- In adult, 0.5 ml per KG per hour, In children, 1 ml per KG per hour
- Adequate fluid resus save the middle zones of stasis and outer zone of hyperaemia
- Under resus acute kidney injury
- Over resus worsen compartment syndrome and pulmonary oedema
32
Pain relief
- Minor burns: NSAIDS, paracetamol, ibuprofen
- Severe burns: IV opioids such as morphine/fentanyl
2-5 mg morphine repeated every 5 min
33
How to assess perfusion?
Assess capillary return and neurovascular perfusion regularly
Circumferential extremity burns may obstruct venous return and capillary flow
Elevate limbs
Contact burns unit
34
How to assess the effectiveness of ventilation?
- Full thickness burns --> leathery necrotic eschar
Covers and pressures neck, chest, extremities --> impaired perfusion --> compartment syndrome
Neck/chest --> compress trachea + breathing
Perform escharotomy
35
What are some lab investigations?
- Baseline CBE: Hb + haematocrits --> inc due to dehydration, haemolysis, neutropenia + thrombocytopenia --> sepsis
- EUC: hyperkalaemia and hyponatremia occur in acute phase due to cell lysis
- Inc Creatinine: acute renal injury
- Serum protein and albumin levels: hypoalbuminaemia --> due to inc cell permeability and loss through burn
- Blood group and hold
- Carboxyhaemoglobin --> CO poisoning, as CO has high affinity to haemoglobin --> haemoglobin hold onto oxygen more tightly not letting O2 diffuse into tissues
- ABG --> hypoxemia, metabolic/resp acidosis (inc anaerobic metabolism), inhalation injury
- Cardiac enzymes, ECG
- Urinalysis
- X-rays, FAST scan
- Electrical burns: continuous cardiac monitor --> cardiac arrhythmia, rhabdomyolysis --> myoglobin leads to acute renal tubules necrosis
36
tetanus
Give tetanus toxoid: if not received in past 5 years
| Tetanus immunoglobulin: not received primary series during childhood
37
What are nutritional and emotional support?
Insert naso-enteric tube: >20% burn
Nutritional support: Vit and trace elements: Vit A/C/D/E/K, folate, Fe, Zn
Emotional support
Clinical psychologist and social worker
38
What is escharotomy?
- Divide inelastic burned skin and incision DOE NOT extend deeply into underlying fat
- Eschar tissue should be debrided to prevent infection
Remove thin layers of necrotic tissue to show uniform capillary bleeding --> reach viable tissue
- Considerable damage to underlying structures: peroneal nerve outside the knee, radial nerve & cephalic vein at wrist, ulnar nerve at elbow, great saphenous vein and nerve at ankle
39
Why we need to administer PPI?
- Inc risk of stress peptic ulcer/Curling’s ulcer (hypovolaemia --> hypoperfusion --> mucosal ischaemia)
40
What are different ways of skin grafts?
split skin: relies on transplant site having dermal papillae --> not good for deep and full thickness burns --> better coverage and more readily available
full thickness --> good for face and special areas
- Allograft (from another person), autograft (from self), xenograft (from pig)
41
What are some post burn management
Skincare
- Avoid unnecessary sun exposure
- Avoid perfumed soap
- Apply moisturisers > twice daily
- Itch management including antihistamines, lukewarm water
Scar management
- Massage and compression, biobrane, surgery
Multidisciplinary approach of management
- Physiotherapy and rehab
- Occupational therapist minimise scarring and contractures
- Psychotherapy psychiatrists, psychologist
- Dermatologist
- Social worker financial and social circumstances
42
What is burn infection?
Risk factors for burn infections
- Loss of natural barrier, surrounding oedema, compartment syndrome
- Diabetes, renal failure, carriage of multi-resistant organisms: MRSA
Causative organisms
- G+: Staphylococcus aureus, MRSA (vancomycin), VRE (vancomycin-resistant enterococcus)
- G-: Pseudomonas aeruginosa (cefepime), E.coli, Klebsiella pneumoniae
- Fungal infections: candida, aspergillus
- Viral: herpes simplex virus, cytomegalovirus, varicella-zoster virus
First 48 hours, G+ staph + strep pyogenes
2-21 days G- pseudomonas aeruginosa
Later fungi and complicated earlier infections
Antibiotics
- Topical is preferred as systemic is less effective as blood flow might be compromised to bring about antibiotics
- ESPECIALLY pseudomonas aeruginosa 4 days after burns most common cause of sepsis
- Staphylococcus aureus is the first pathogen to enter
43
What are some topical agents?
Silver sulfadiazine
- G+ and G-, pseudomonas aeruginosa
- Leukopenia
Silver nitrate
- give to sulfa allergies (Silver sulfadiazine can’t be used)
- against aerobic G-, pseudomonas aeruginosa
- Electrolytes imbalance
Mafenide acetate
- Broad spectrum against aerobic G-, pseudomonas aeruginosa
- Metabolic acidosis
Nanocrystalline silver
- G-: pseudomonas aeruginosa
G+: MRSA, VRE
- Limited toxicity
44
How to investigate burn infections?
- Superficial swabs
| - Culture of burn biopsies
45
What are some prevention to burn infection?
- Handwashing
- Patient isolation in single room
- Gowns, gloves, masks while burn dressing
- Routine wound, sputum and urine culture
46
What are some pain medications?
Paracetamol
Opioids
- morphine
- codeine
- oxycodone
- fentanyl
47
What is paracetamol
MOA: UNCLEAR
MAX 4g per day for adult
Suitability: hepatic impairment --> low dose
Metabolised via liver. Metabolised to toxic metabolite --> hepatoxicity with moderate overdose
Side effect: therapeutic dose can raise LFT but not associated liver damage
48
What is opioids?
MOA: Work at opioid receptors, mainly mu receptor (high density in parts of brain, peripheral sites such as gut, bladder, vessels)
Suitability: Previous reaction (allergy is rare but intolerance is common), renal function
Side effect
Short term
- Acute: sedation, dysphoria, resp depression, nausea
Acute peripheral: constipation (prescribe laxatives as well), urinary retention, biliary spasm, itch/histamine release, vasodilation and hypotension
Long term
- tolerance, withdrawal (diarrhoea, sweating, chills, restlessness, craving), addiction, hyperalgesia (inc response to a stimulus which is normally painful) --> inc pain sensitivity to other painful stimuli --> chronic pain somewhere else
Long-term prescription short-term 1 or 2 weeks, NOT LONG TERM
49
What some types of opioids?
Codeine prescribed
- Weak affinity for mu acceptor
- 10% metabolised to morphine
- More likely to cause nausea self-limiting in overdose
Oxycodone
- Alternative to morphine
- Preferred to elderly patient with renal impairment
Fentanyl
- Potent, comes as IV and patch
- Rapid onset, tolerance issues when long-term use
50
How to choose to prescribe which opioids?
No evidence has shown one opioid is better than the other in terms of safety or efficacy, so selection is based on
- Previous patient experience: efficacy and adverse effects
- Other comorbidities: renal function
- Route: not all drugs
