BURNS, INTRODUCTION, PATHOPHYISOLOGY AND MANAGEMENT

A brief of management of burns from standard textbook for mbbs undergraduates and surgery residents and surgeons taken from standard textbook

1. BURNS Pathophysiology and principles of management Maj DS Dinakaran JR-II Gen Surgery

2. Pathophysiology and Principles of Management General Consideration Pathophysiology Management Chemical Burns Electric Burns

3. General Consideration In 2017, 400,000 burns cases - 3400 died (almost 1%) Over years (2001 – 2017) – incidence decreased (23%) , death from burns (10%) Children (0-18) – Decreasing Adults (19- 65) – Moderate decrease Elderly >65 years – Increasing Sabiston Textbook of Surgery, 21 st Edition

4. General Consideration Indian Statistics: - 70 lakh burn injury cases annually - 1.4 lakh people die of burn every year. - Around 4/5 are women & children. - As many as 80% of cases admitted are a result of accidents at home (kitchen-related incidents) - Around 70% of all burn injuries occur in most productive age group (15-35 years).

5. General Consideration Dr Basil A Pruitt “ Burns is a universal trauma model” Sabiston Textbook of Surgery, 21 st Edition

6. General Consideration Bimodal Distribution of Mortality Sabiston Textbook of Surgery, 21 st Edition

7. General Consideration 41 % Thermal 33% Scalding 9% Contact 3% Chemical 3% Electrical 2/3 rd Burns - Household Sabiston Textbook of Surgery, 21 st Edition

8. General Consideration Sabiston Textbook of Surgery, 21 st Edition Smoking- 22% of House fires

9. General Consideration Probit Analysis LD 50- 55% TBSA Sabiston Textbook of Surgery, 21 st Edition

10. General Consideration Baux Score: Dr Francis Baux 1960 Age + TBSA + (17 x R) R-1/0 Inference: Score > 150 little or no chance of survival LD 50 – 105 LD 90 – 130 Sabiston Textbook of Surgery, 21 st Edition

11. General Consideration Birmingham Burns Centre, UK (LD50) 1940 <14 year - 49% <15-44 – 46% < 45-65 – 27% >65 - 10% Latest <14 year - 85% <15-44 – 66% < 45-65 – 46% >65 - 23% Sabiston Textbook of Surgery, 21 st Edition

12. Burn Unit Sabiston Textbook of Surgery, 21 st Edition Gilles and Mcindoe in UK

13. Burn Unit Sabiston Textbook of Surgery, 21 st Edition Experienced burns surgeons Dedicated nursing personnel Physical and occupation therapist Social worker Dietician Respiratory therapist Psychiatrist and phycologist Prosthetics

14. Burn Unit Sabiston Textbook of Surgery, 21 st Edition Indication Partial thickness > 10%TBSA Any full thickness Electric burns including lightning injury Chemical burns Inhalational injury Face, hand, feet, genitalia, perineum or major joints Comorbidities that could affect outcome Burns and concomitant trauma (ex: fracture) Children in hospital without qualified personnel / equipment Patient benefitting for long term rehab

15. Pathophysiology Biological tolerance - Membrane Disruption - Protein Denaturation - Necrosis Injury - Temp - Duration Sabiston Textbook of Surgery, 21 st Edition

16. Pathophysiology Temp > 280° - Millard Type Reaction – Change in colour and consistency with full thickness burns Temp < 280° - Necrosis of the surface eg :- Scald burns Sabiston Textbook of Surgery, 21 st Edition

17. Pathophysiology Thermal Conductivity - Water – 0.61 w/m/°c - Cooking oil – 4.2 joules /g ° c - Grease – 1.8 joule /g °C Sabiston Textbook of Surgery, 21 st Edition

18. Classification Cause Plane – super heated oxidized air by convection / radiation Scald – hot liquid Contact – hot / cold solids Chemical – noxious chemical Electrical – conduction of electric current Sabiston Textbook of Surgery, 21 st Edition

19. Classification Superficial – epidermis Superficial partial thickness – epidermis/papillary dermis Deep partial – reticular dermis Full thickness – subcutaneous fat Sabiston Textbook of Surgery, 21 st Edition

20. Depth - Superficial Confined to epidermis Blanched to touch Erythematous Painful Sabiston Textbook of Surgery, 21 st Edition

21. Superficial Partial Thickness Blanch to touch Erythematous Painful Blisters Retention of hair follicles to gentle pulling Heal in 1-14 days Sabiston Textbook of Surgery, 21 st Edition

22. Superficial Partial Thickness Bailey & Love’s short practice of surgery Ed 28

23. Deep Partial Thickness Pale and Mottled Do not blanch on touch Painful to pin prick Heal in 14 to 21 days with severe scarring Sabiston Textbook of Surgery, 21 st Edition

24. Full Thickness Burns Hard leathery Eschar Painless Benefit from excision of Eschar May involve muscles and bone Sabiston Textbook of Surgery, 21 st Edition

25. Full Thickness Burns Bailey & Love’s short practice of surgery Ed 28

26. Zones Coagulation Necrotic area of burn, irreversibly damaged Stasis Moderate degree of insult with decreased tissue perfusion Tissue may either survive or Coagulative necrosis , Associated vascular damage or vessel leakage Hyperaemia Vasodilation Viable tissue Healing process begins Sabiston Textbook of Surgery, 21 st Edition

27. Zones Sabiston Textbook of Surgery, 21 st Edition

28. Burn Size RULE OF NINE Equate area of open hand ( palm & fingers ) to 1% TBSA Berkows used in children Sabiston Textbook of Surgery, 21 st Edition

29. Bailey & Love’s short practice of surgery Ed 28

30. Systemic Changes INFLAMMATION AND EDEMA - local mediators induces vasoconstriction, vasodilation, Increased capillary permeability, Edema (Plasma osmotic pressure decrease, interstitial osmotic pressure increases ) Sabiston Textbook of Surgery, 21 st Edition

31. Mediators Histamine Bradykinin Vasoactive amine Prostaglandin Leukotrienes Activated complexes Catecholamine Glycocalyx form plasma membrane Sabiston Textbook of Surgery, 21 st Edition

32. Effects on CVS Serotonin from Platelets - pulmonary resistance and increased vasoconstriction by vasoactive amines Loss of plasma volume Decreased cardiac output - Decreased blood volume - Increased viscosity - Decreased cardiac contractility ( due to circulating myocardial depressor factors in lymphatic fluid) Sabiston Textbook of Surgery, 21 st Edition

33. Effects on Renal System Decreased renal blood flow - Decrease in GFR  oliguria  Acute tubular necrosis  Renal failure Other hormones involved – angiotensin, aldosterone, vasopressin 28-day mortality and in hospital mortality in severe burns with renal failure Decreased by 50- 25% with Continuous venovenous hemofiltration Sabiston Textbook of Surgery, 21 st Edition

34. Effects of Immune System Global depression in immune function adaptive immunity down regulation Increased bacterial infection/ Pneumonia/ fungal / Viral infection Macrophage production decreases Neutrophils initially increases later decreased due to apoptosis Those present, dysfunctional in terms of – diapedesis , chemostasis , phagocytosis T cell function decreased in severe burns Sabiston Textbook of Surgery, 21 st Edition

35. Hypermetabolism 3-4 days after injury Tachycardia Increased energy expenditure Increased O2 consumption Massive proteolysis and lipolysis release of catecholamines, glucocorticoids, insulin, glucagon. Sabiston Textbook of Surgery, 21 st Edition

36. Hypermetabolism Massive weight loss Catecholamines  pancreas Beta receptors  Increase in glucagon/ Increase in insulin Alpha receptors  Decrease in insulin > glucagon - net effect increase in glucagon Increase in lipolysis  Compromise of processing lipid by liver -> fatty liver (NAFLD) Sabiston Textbook of Surgery, 21 st Edition

37. Sabiston Textbook of Surgery, 21 st Edition

38. Initial Treatment of Burns – Pre Hospital Remove from source & burning process stopped Rings / jewellery to be removed – prevent tourniquet effect Copious room temperature water < 3 hours of injury – decrease depth of wound , improve healing and scarring Water > 3 hrs may lead to hypothermia Transfer to hospital earliest Sabiston Textbook of Surgery, 21 st Edition

39. Initial Assessment Primary + secondary survey undertaken Inhalation injury – edema of airway (min- hour) Suspect inhalation when Facial burns Singed nasal hair Carbonaceous sputum Tachypnoea Progressive hoarseness Sabiston Textbook of Surgery, 21 st Edition

40. Initial Assessment Prophylactic intubation TBSA > 40% BP may not be accessed - Doppler distal examination - Arterial pressure measurement - Urine output monitoring Other injuries Cervical spine fractures Sabiston Textbook of Surgery, 21 st Edition

41. Resuscitation IV access Veins of burned skin may be used Saphenous vein cut down preferred over central venous catheter In children <6 years of age intramedullary access done in proximal tibia RL is fluid of choice except for children > 2 yrs 5% Dextrose for children <2 yrs Sabiston Textbook of Surgery, 21 st Edition

42. Resuscitation

43. Fluid Initial rate of fluid is TBSA ×10 , Example:- 40% TBSA = 400ml/h until formal calculation Parkland – 4ml /kg / % TBSA (max 50% TBSA) Brooks – 2ml /kg / % TBSA Galveston (children) – 5000ml/m2 burned + 1500ml /m2 TBSA

44. Fluid Colloid not used in 24hrs. Although fluid is Institutional policy - hourly urine output mandatory for assessing resuscitation Goal – 0.5ml/kg/hr in adult 1ml/kg/hr in children

45. Galveston 5000 ml/m2 per TBSA burn in m2 + 1500ml/m2 TBSA for maintainable in first 24h . Half given in 8 hour next ½ in rest 24 h

46. Other Precautions Aspiration – NG tube NPO till transport completed Apprehensive patient swallow air causing distended stomach TT immunization for pt >10 % TBSA LAST DOSE (not known /> 10years ) – 250U of tetanus immunoglobulin

47. Escharotomy With deep partial or full thickness encompassing complete circumference of extremity  peripheral circulation compromised  pressure > 30mmHg Bed side- lateral + medial aspect of extremity incised with scalpel/diathermy If reperfusion  increased edema  fasciotomy done . Constricting truncal escharotomy if decreased ventilation , decreased chest movement .

48. Escharotomy

49. Escharotomy Bailey & Love’s short practice of surgery Ed 28

50. Inhalational Burns One major cause of death Damage due to chemical burns due to inhalation of toxins Upper airway – dispersion of heat Lower airway – cooled particles + toxins Exception high pressure steam, 4000times heat than dry air

51. Inhalational Burns Bailey & Love’s short practice of surgery Ed 27

52. Effects Immediate effect Increased bronchial blood flow  edema  increased lung lymph flow Separation of ciliated epithelial cells from basement membrane  exudate formation Exudate consist protein which coalesce to form fibrin cast. These cast acts as ball and valve allow inspiration and not expiration causing pneumothorax and decreased lung compliance Definitive diagnosis- Bronchoscopy ( erythema , ulceration , infraglottic soot

53. Inhalational Burns Definitive diagnosis- Bronchoscopy (erythema, ulceration, infraglottic soot)

54. Initial Treatment Mechanical ventilation Repeat Bronchoscopy – continued ulceration Granulation tissue formation Exudate formation Inspisation of secretion Focal edema Eventually heals by sloughing of cuboidal ciliated epithelium with squamous cells and scar

55. CO and HCN- Systemic Effects Absorption may lead to death CO inhalation presumed in all cases – crosses pulmonary capillary membrane and bind to Hb with 200 times more affinity, conformational changes in Hb.

56. CO and HCN- Systemic Effects Diminishes off loading ability in peripheral tissues Intracellular CO, bind to cytoplasmic C oxidase, disrupt electron transport chain  shift from aerobic to anaerobic metabolism. Increase oxidative stress Affects high metabolic organs such as brain , heart , therefore manifest as neurological change such as arrhythmia and infraction .

57. HCN HCN used in synthetic material in construction and home furnishing Increased HCN poisoning during house fires

58. CO Poisoning Carboxyhemoglobin level with elevation >5 % Symptoms 10% Dizziness 20% impaired judgment 30% dyspnoea 40% seizure, syncope Inhalational Treatment Decrease ½ life of carboxyhemoglobin from 4h to 1h Hydroxycobalamine given IV

59. Stages of Inhalational Injury First Stage Acute pulmonary insufficiency – beginning of pulmonary failure No clinical feature of parenchymal damage not common

60. Second stage 72 – 96h Extravascular lung fluid  hypoxia Diffuse lobar infiltrates Similar to ARDS

61. Third stage 3- 10 days bronchopneumonia Org Staphylococcus species initially After7-8 days – Pseudomonas & Klebsiella

62. Management of Inhalational Injury Intubation if required Frequent Bronchoscopy to clear inspissated secretion Heparin nebulization- decrease tracheal bronchial cast formation NAC nebulization- decrease re-intubation, mortality rate

63. Management of Inhalational Injury Hypertonic saline Prophylactic antibiotics not indicated Empirical choice of Rx of Pneumonia- MRSA , Gram positive, Gram negative organisms Suctioning

64. Wound Care Splinting to maintain desired position of function Occlusive dressing to minimize evaporation, heat loss and minimize cold stress. Superficial wound no dressing indicated

65. Wound Care Partial thickness – daily dressing with topical antibiotics or long lasting dressing with silver Temporary cover- biologic/ synthetic cover Xenograft Allograft

66. Wound Care

67. Wound Care Deep partial and full thickness - Excision and grafting Antimicrobial Use Bacterial proliferation > 100/g of tissue-> penetrate into viable tissue Topical – Salve, Soaks, Antimicrobial dressing Salve silver sulphadiazine, mafenide acetate 11% Gram + - Bacitracin, neomycin Gram negative- polymyxin B Fungal – nystatin

68. Wound Care Solutions :- Silver nitrate 0.5% 5% mafenemic acetate Dakin solution – 0.5% sodium hypochlorite with buffers Domboro‘s solution – 0.25 % acetic acid with buffer Antimicrobial dressing:- Silver dressing Salve- applied over wound Soaks- poured into Colton dressing on ward

69. Wound Care

70. Chemical Burns More industrial than household. Tissue destruction  denaturation  oxidation  protein ester  desiccation of tissues Remove clothes Copious Water eg :- 10ml of 98% H2So4 in 12L in water  decrease pH to 5.0 18 to 20L of tap water Acid – coagulation necrosis Base – liquefaction necrosis ( penetrate deep)

71. Alkali Lime Potassium Hydroxide Bleach Sodium hydroxide

72. Hydrofluoric Acid Both industrial/ domestic Strongest inorganic acid Cause corrosion, with free hydrogen ion Systemic effects  fluoride ion caused intravascular calcium chelation  hypocalcemia  arrhythmia. Treatment- Copious tap water Wound with 2.5% calcium gluconate gel Intradermal + intramuscular Calcium gluconate in affected extremity All patient admitted for calcium monitoring

73. Chemical Burns

74. Electric Burns 3- 5 % patient admitted for electric burns Visible areas of necrosis, less compared to actual injury Current enter through finger/hand spreads through tissues with low resistance generally nerves, vessels, muscles Muscle damage is most prominent Blood vessel may get thrombosed leading to ischemia

75. High Voltage Burns Burns are both thermal and electric If VF  cardiac arrest  CPR

76. Low Voltage House hold current Children bite into wires (AC) burns mostly electric.

77. Treatment Chance of being thrown from electric jolt or falling Violent contraction cause- dislocation, fractures Deep tissue injury causes edema  vascular compromise May require escharotomy / fasciotomy If excessive muscle necrosis  amputation Early debridement  later SSG/ flap cover

78. 79

79. Treatment Muscle damage  myoglobin  filtered by glomeruli  obstructive nephropathy Treatment- hydration IV Sodium Bicarbonate 5% Mannitol 25g Q6H

80. Organ Failure 28% Pt with > 20% TBSA- MODS of which 14% patient severe sepsis and shock Renal FAILURE 1 ST HIT – Immediately 2 ND HIT – 2 -14 days after resuscitation Urine output 1ml/kg /hr in children 0.5ml /kg/hr in adults

81. Nutrition