Burn Shock: Difference between revisions
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== Introduction == | == Introduction == | ||
[[Shock]] is a medical emergency and it occurs when the body's tissues and organs are deprived of adequate oxygenated blood. Burn shock is a term used to describe certain signs such as: decreased cardiac output, increased vascular resistance, hypovolaemia and hypoperfusion that occur after severe [[Burns Overview|burn]] injuries have been sustained<ref name=":0">Schaefer TJ, Nunez Lopez O. [https://www.ncbi.nlm.nih.gov/books/NBK430795/#_NBK430795_pubdet_ Burn Resuscitation And Management]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2020 | [[Shock]] is a medical emergency and it occurs when the body's tissues and organs are deprived of adequate oxygenated blood. Burn shock is a term used to describe certain signs such as: decreased cardiac output, increased vascular resistance, hypovolaemia and hypoperfusion that occur after severe [[Burns Overview|burn]] injuries have been sustained<ref name=":0">Schaefer TJ, Nunez Lopez O. [https://www.ncbi.nlm.nih.gov/books/NBK430795/#_NBK430795_pubdet_ Burn Resuscitation And Management]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2020 | ||
</ref>. This incident leads to the release of inflammatory substances such as histamines and prostaglandins into the circulation resulting in large movements of fluid from the capillary space. Burn shock mostly occurs within the first | </ref>. This incident leads to the release of inflammatory substances such as histamines and prostaglandins into the circulation resulting in large movements of fluid from the capillary space. Burn shock mostly occurs within the first 24 hours after sustaining burn injuries with its peak levels at 6 to 8 hours after the injury<ref name=":0" />. It may extend up to 2 to 3 days and last longer in the elderly population<ref name=":4" />. | ||
==Pathophysiology of Burn Shock== | ==Pathophysiology of Burn Shock== | ||
The interaction between hypovolaemia, direct tissue and anti-inflammatory substances in the body cause burn shock<ref name=":4">Wurzer P, Culnan D, Cancio LC, Kramer GC. [https://www.sciencedirect.com/science/article/pii/B9780323476614000083 8-Pathophysiology of Burn Shock and Burn Edema.] In: Herndon DN. Total Burn Care (Fifth Edition). Elsevier, 2018. p66-76</ref>. Soon after burn injuries occur, Starling forces which determine the directionality of net water movement between different compartments begin to allow fluid to move from blood to both tissues that have and have not been damaged by burn injuries<ref name=":4" />. The formation of [[Edema Assessment|oedema]] (increased interstitial fluid) that soon follows burn injuries is mainly due to the creation of a strong negative interstitial fluid pressure and increased capillary permeability (otherwise known as capillary leakage syndrome)<ref name=":4" />. Oedema reaches maximal levels in burn areas after | The interaction between hypovolaemia, direct tissue and anti-inflammatory substances in the body cause burn shock<ref name=":4">Wurzer P, Culnan D, Cancio LC, Kramer GC. [https://www.sciencedirect.com/science/article/pii/B9780323476614000083 8-Pathophysiology of Burn Shock and Burn Edema.] In: Herndon DN. Total Burn Care (Fifth Edition). Elsevier, 2018. p66-76</ref>. Soon after burn injuries occur, Starling forces which determine the directionality of net water movement between different compartments begin to allow fluid to move from blood to both tissues that have and have not been damaged by burn injuries<ref name=":4" />. The formation of [[Edema Assessment|oedema]] (increased interstitial fluid) that soon follows burn injuries is mainly due to the creation of a strong negative interstitial fluid pressure and increased capillary permeability (otherwise known as capillary leakage syndrome)<ref name=":4" />. Oedema reaches maximal levels in burn areas after 24 hours of burn occurrence<ref name=":3">Ishikawa T, Maeda H. [https://doi.org/10.1016/B978-0-12-382165-2.00162-8 Sytemic Response to Trauma. In: Siegel JA, Saukko PJ, Houck MM. Encyclopedia of Forensic Sciences (Second Edition).] Academic Press, 2013. p47-53</ref>. Fluid loss from the blood is also accompanied by the extravasation of proteins and electrolytes<ref name=":2">Dean S. Management of burns and plastic surgery. In: Porter S editor. Tidy's Physiotherapy (14th Edition). Churchill Livingstone: Elsevier, 2009. p95-112.</ref> resulting in severe hypoproteinaemia and electrolyte imbalance. A reduction in cardiac output which is a notable feature of burn shock occurs from an interaction between hypovolaemia, an increase in ventricular afterload and a decreased contractility of the myocardium.<ref name=":3" /> | ||
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== Management of Burn Shock == | == Management of Burn Shock == | ||
Burn shock is better prevented or minimized than treated. The administration of fluid [[Cardiopulmonary Resuscitation|resuscitation]] promptly, within the first | Burn shock is better prevented or minimized than treated. The administration of fluid [[Cardiopulmonary Resuscitation|resuscitation]] promptly, within the first 24 hours of the occurrence of burn injuries is crucial, especially when burns are extensive and above 20% of the total burn surface area in both adults and children<ref name=":0" />. Fluid resuscitation is primarily aimed at the maintenance of vital organ function while also avoiding the complications that may stem from over and under resuscitation<ref>Dries DJ. [https://sjtrem.biomedcentral.com/articles/10.1186/s13049-020-00792-z#Sec3 Burn care: before the burn centre.] Scand J Trauma Resusc Emerg Med. 2020; 28(97)</ref>. The Parkland formula is mostly used to determine the amount of fluid to infuse. It is given as: | ||
'''Four mL lactated ringers solution × percentage total body surface area (%TBSA) burned × patient's weight in kilograms = total amount of fluid given in the first 24 hours.''' | '''Four mL lactated ringers solution × percentage total body surface area (%TBSA) burned × patient's weight in kilograms = total amount of fluid given in the first 24 hours.''' | ||
It is advised that one-half of the quantity of the fluid obtained from the formula be administered over the first | It is advised that one-half of the quantity of the fluid obtained from the formula be administered over the first 8 hours post thermal injury while the second half should be given over the next 16 hours<ref name=":1">Jeng JC, Bowyer MW. Burns. In: Parsons PE, Wiener-Kronish JP. [https://www.sciencedirect.com/science/article/pii/B9781416032069100679 Critical Care Secrets (Fourth edition)] Mosby: Elsevier, 2007.</ref>. The formula only serves to determine the initial fluid rate which is thereafter adjusted to achieve an hourly [[Urinary Tract Infection|urine]] output between 30 and 50 mL in a 70-kg adult with urine output being an important factor that guides fluid management <ref name=":1" /><ref>Tsarouhas N, Agosto P. Burns. In: Baren JM, Brennan JA, Rothrock SG, Brown L. [https://www.sciencedirect.com/topics/medicine-and-dentistry/burn-shock Paediatric Emergency Medicine]. Saunders: Elsevier, 2008. p1285-1320.</ref>. It is important to achieve optimal fluid resuscitation as an under-resuscitation can lead to acute kidney injury, reduced perfusion and death, while an over-resuscitation may result in: massive oedema formation, [[Compartment Syndrome|compartment syndrome]], [[Acute Respiratory Distress Syndrome (ARDS)|acute respiratory distress syndrome]] and multiple organ dysfunction<ref>Weavind L. Critical Care Medicine: Burn Shock, Resuscitation of Burn Shock, Burn Shock Resuscitation. Available from: https://www.cancertherapyadvisor.com/home/decision-support-in-medicine/critical-care-medicine/burn-shock-resus<nowiki/>citation-of-burn-shock-resuscitation/</ref>. | ||
====Contraindications to Fluid Resuscitation==== | ====Contraindications to Fluid Resuscitation==== | ||
Revision as of 05:13, 16 March 2022
Original Editor - Cindy John-Chu
Top Contributors - Cindy John-Chu, Kim Jackson, Chelsea Mclene and Lucinda hampton
Introduction[edit | edit source]
Shock is a medical emergency and it occurs when the body's tissues and organs are deprived of adequate oxygenated blood. Burn shock is a term used to describe certain signs such as: decreased cardiac output, increased vascular resistance, hypovolaemia and hypoperfusion that occur after severe burn injuries have been sustained[1]. This incident leads to the release of inflammatory substances such as histamines and prostaglandins into the circulation resulting in large movements of fluid from the capillary space. Burn shock mostly occurs within the first 24 hours after sustaining burn injuries with its peak levels at 6 to 8 hours after the injury[1]. It may extend up to 2 to 3 days and last longer in the elderly population[2].
Pathophysiology of Burn Shock[edit | edit source]
The interaction between hypovolaemia, direct tissue and anti-inflammatory substances in the body cause burn shock[2]. Soon after burn injuries occur, Starling forces which determine the directionality of net water movement between different compartments begin to allow fluid to move from blood to both tissues that have and have not been damaged by burn injuries[2]. The formation of oedema (increased interstitial fluid) that soon follows burn injuries is mainly due to the creation of a strong negative interstitial fluid pressure and increased capillary permeability (otherwise known as capillary leakage syndrome)[2]. Oedema reaches maximal levels in burn areas after 24 hours of burn occurrence[3]. Fluid loss from the blood is also accompanied by the extravasation of proteins and electrolytes[4] resulting in severe hypoproteinaemia and electrolyte imbalance. A reduction in cardiac output which is a notable feature of burn shock occurs from an interaction between hypovolaemia, an increase in ventricular afterload and a decreased contractility of the myocardium.[3]
Clinical Features of Burn Shock[edit | edit source]
- Hypovolaemia
- Increased blood viscosity due to increased ratio of red blood cells to plasma
- Reduced cardiac output
- Increased heart rate[4]
Management of Burn Shock[edit | edit source]
Burn shock is better prevented or minimized than treated. The administration of fluid resuscitation promptly, within the first 24 hours of the occurrence of burn injuries is crucial, especially when burns are extensive and above 20% of the total burn surface area in both adults and children[1]. Fluid resuscitation is primarily aimed at the maintenance of vital organ function while also avoiding the complications that may stem from over and under resuscitation[7]. The Parkland formula is mostly used to determine the amount of fluid to infuse. It is given as:
Four mL lactated ringers solution × percentage total body surface area (%TBSA) burned × patient's weight in kilograms = total amount of fluid given in the first 24 hours.
It is advised that one-half of the quantity of the fluid obtained from the formula be administered over the first 8 hours post thermal injury while the second half should be given over the next 16 hours[8]. The formula only serves to determine the initial fluid rate which is thereafter adjusted to achieve an hourly urine output between 30 and 50 mL in a 70-kg adult with urine output being an important factor that guides fluid management [8][9]. It is important to achieve optimal fluid resuscitation as an under-resuscitation can lead to acute kidney injury, reduced perfusion and death, while an over-resuscitation may result in: massive oedema formation, compartment syndrome, acute respiratory distress syndrome and multiple organ dysfunction[10].
Contraindications to Fluid Resuscitation[edit | edit source]
Haemodynamically stable patients may not benefit from fluid resuscitation as this may lead to oedema[1].
Complications of Burn Shock[edit | edit source]
May include:
- Acute renal failure
- Decreased perfusion
- Pulmonary oedema
- Liver failure
- Cardiac failure
- Occlusion of arteries
- Permanent brain damage
- Death[4]
Role of the Physiotherapist[edit | edit source]
Physiotherapists may not be directly involved in the management of burn shock but, it is pertinent to still have a knowledge about it since we will be involved in the rehabilitation of patients with burn injuries from their inception into the burn care unit.
References[edit | edit source]
- ↑ 1.0 1.1 1.2 1.3 Schaefer TJ, Nunez Lopez O. Burn Resuscitation And Management. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2020
- ↑ 2.0 2.1 2.2 2.3 Wurzer P, Culnan D, Cancio LC, Kramer GC. 8-Pathophysiology of Burn Shock and Burn Edema. In: Herndon DN. Total Burn Care (Fifth Edition). Elsevier, 2018. p66-76
- ↑ 3.0 3.1 Ishikawa T, Maeda H. Sytemic Response to Trauma. In: Siegel JA, Saukko PJ, Houck MM. Encyclopedia of Forensic Sciences (Second Edition). Academic Press, 2013. p47-53
- ↑ 4.0 4.1 4.2 Dean S. Management of burns and plastic surgery. In: Porter S editor. Tidy's Physiotherapy (14th Edition). Churchill Livingstone: Elsevier, 2009. p95-112.
- ↑ 100lyric. Easy Ways to Understand Pathophysiology of Burn. Available from: https://youtu.be/et-vGjKWYBc [last accessed 30/11/2020]
- ↑ Dr John Campbell. Burns 12, Systemic effects- Circulation. Available from:https://youtu.be/eLNbrCS_Ymg [last accessed 30/11/2020]
- ↑ Dries DJ. Burn care: before the burn centre. Scand J Trauma Resusc Emerg Med. 2020; 28(97)
- ↑ 8.0 8.1 Jeng JC, Bowyer MW. Burns. In: Parsons PE, Wiener-Kronish JP. Critical Care Secrets (Fourth edition) Mosby: Elsevier, 2007.
- ↑ Tsarouhas N, Agosto P. Burns. In: Baren JM, Brennan JA, Rothrock SG, Brown L. Paediatric Emergency Medicine. Saunders: Elsevier, 2008. p1285-1320.
- ↑ Weavind L. Critical Care Medicine: Burn Shock, Resuscitation of Burn Shock, Burn Shock Resuscitation. Available from: https://www.cancertherapyadvisor.com/home/decision-support-in-medicine/critical-care-medicine/burn-shock-resuscitation-of-burn-shock-resuscitation/
