Pathophysiology and types of burns

Understanding the pathophysiology of a burn injury is important for effective management. In addition, different causes lead to different injury patterns, which require different management. It is therefore important to understand how a burn was caused and what kind of physiological response it will induce. Burn injuries result in both local and systemic responses. ![][1] Clinical image of burn zones. There is central necrosis, surrounded by the zones of stasis and of hyperaemia ### Local response The three zones of a burn were described by Jackson in 1947. Zone of coagulation —This occurs at the point of maximum damage. In this zone there is irreversible tissue loss due to coagulation of the constituent proteins. Zone of stasis —The surrounding zone of stasis is characterised by decreased tissue perfusion. The tissue in this zone is potentially salvageable. The main aim of burns resuscitation is to increase tissue perfusion here and prevent any damage becoming irreversible. Additional insults—such as prolonged hypotension, infection, or oedema—can convert this zone into an area of complete tissue loss. Zone of hyperaemia —In this outermost zone tissue perfusion is increased. The tissue here will invariably recover unless there is severe sepsis or prolonged hypoperfusion. These three zones of a burn are three dimensional, and loss of tissue in the zone of stasis will lead to the wound deepening as well as widening. ![][2] ackson's burns zones and the effects of adequate and inadequate resuscitation ### Systemic response The release of cytokines and other inflammatory mediators at the site of injury has a systemic effect once the burn reaches 30% of total body surface area. Cardiovascular changes —Capillary permeability is increased, leading to loss of intravascular proteins and fluids into the interstitial compartment. Peripheral and splanchnic vasoconstriction occurs. Myocardial contractility is decreased, possibly due to release of tumour necrosis factor α. These changes, coupled with fluid … [1]: /embed/graphic-1.gif [2]: /embed/graphic-2.gif

[1]  T. Pickering,et al.  Management of hypertension in the elderly using home blood pressures , 2001, Blood pressure monitoring.

[2]  S. Stahl,et al.  Effects of home blood pressure measurement on long-term BP control. , 1984, American journal of public health.

[3]  John E. Stollerman,et al.  A telecommunications system for monitoring and counseling patients with hypertension. Impact on medication adherence and blood pressure control. , 1996, American journal of hypertension.

[4]  R. Agarwal,et al.  Home blood pressure monitoring in CKD. , 2005, American journal of kidney diseases : the official journal of the National Kidney Foundation.

[5]  B. Martina,et al.  Reliability of patients measuring blood pressure at home: prospective observational study , 1999, BMJ.

[6]  N. Poulter,et al.  Improved Hypertension Management and Control: Results From the Health Survey for England 1998 , 2001, Hypertension.

[7]  D. Kromhout.  Cholesterol, diastolic blood pressure, and stroke: 13 000 strokes in 450 000 people in 45 prospective cohorts , 1995, The Lancet.

[8]  M. Aylett,et al.  Home blood pressure monitoring: its effect on the management of hypertension in general practice. , 1999, The British journal of general practice : the journal of the Royal College of General Practitioners.

[9]  M. Rogers,et al.  Home Monitoring Service Improves Mean Arterial Pressure in Patients with Essential Hypertension: A Randomized Controlled Trial , 2001 .

[10]  H. Martin,et al.  Non-accidental burns in children. , 1998, Burns : journal of the International Society for Burn Injuries.

[11]  P. Mooney,et al.  Objective measurement of anxiety in hypertensive pregnant women managed in hospital and in the community , 1992, British journal of obstetrics and gynaecology.

[12]  J. Earp,et al.  The effects of family involvement and practitioner home visits on the control of hypertension. , 1982, American journal of public health.

[13]  D. Mant,et al.  Comparison of acceptability of and preferences for different methods of measuring blood pressure in primary care , 2002, BMJ : British Medical Journal.

[14]  E. MacLaughlin,et al.  Effect of Pharmacist Intervention and Initiation of Home Blood Pressure Monitoring in Patients with Uncontrolled Hypertension , 2000, Pharmacotherapy.

[15]  D. Burd,et al.  Hydrofluoric acid burns: a review. , 1995, Burns : journal of the International Society for Burn Injuries.

[16]  C. A. Nugent,et al.  The effects of self-monitoring by patients on the control of hypertension , 1975, The American journal of the medical sciences.

[17]  T. Vogt,et al.  Home Blood Pressure Monitoring: Effect on Use of Medical Services and Medical Care Costs , 1992, Medical care.

[18]  I. Rosenstock,et al.  Linking Research and Practice in Patient Education for Hypertension: Patient Responses to Four Educational Interventions , 1981, Medical care.

[19]  K. Zarnke,et al.  A randomized study comparing a patient-directed hypertension management strategy with usual office-based care. , 1997, American journal of hypertension.

[20]  L. Midanik,et al.  Home blood pressure monitoring for mild hypertensives. , 1991, Public health reports.

[21]  K R Abrams,et al.  Modelling publication bias in meta-analysis: a review. , 2000, Statistical methods in medical research.

[22]  L. Hess,et al.  Influence of self-measurement of blood pressure on the responder rate in hypertensive patients treated with losartan: results of the SVATCH Study , 2000, Journal of Human Hypertension.

[23]  Daniel W. Jones,et al.  The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure: the JNC 7 report. , 2003, JAMA.

[24]  D. Sackett,et al.  IMPROVEMENT OF MEDICATION COMPLIANCE IN UNCONTROLLED HYPERTENSION , 1976, The Lancet.

[25]  R. Collins,et al.  Blood pressure, stroke, and coronary heart disease Part 1, prolonged differences in blood pressure: prospective observational studies corrected for the regression dilution bias , 1990, The Lancet.

[26]  D. Mant,et al.  Comparison of agreement between different measures of blood pressure in primary care and daytime ambulatory blood pressure , 2002, BMJ : British Medical Journal.

[27]  D. Sackett,et al.  Self-recording of blood pressure in the management of hypertension. , 1978, Canadian Medical Association journal.

[28]  J. Staessen,et al.  How to use home blood pressure monitors in clinical practice. , 2002, American journal of hypertension.

[29]  N. Artinian,et al.  Effects of home telemonitoring and community-based monitoring on blood pressure control in urban African Americans: a pilot study. , 2001, Heart & lung : the journal of critical care.

[30]  K. Franklin,et al.  A comparison of compliance techniques on the control of high blood pressure. , 1988, American journal of hypertension.

[31]  J. Pierce,et al.  A controlled trial of health education in the physician's office. , 1984, Preventive medicine.

[32]  I. Mühlhauser,et al.  Evaluation of a structured treatment and teaching programme on hypertension in general practice. , 1993, Clinical and experimental hypertension.

[33]  A. Gillies,et al.  Antihypertensive drug treatment: A comparison of usual care with self blood pressure measurement , 1999, Journal of Human Hypertension.

[34]  W. Garner.  Total Burn Care, 2nd ed. , 2003 .

[35]  J. Hewison,et al.  Antenatal home blood pressure monitoring: a pilot randomised controlled trial , 2000, BJOG : an international journal of obstetrics and gynaecology.

[36]  David R. Jones,et al.  Empirical assessment of effect of publication bias on meta-analyses , 2000, BMJ : British Medical Journal.