Burns treatment, resuscitation in burns, formula, managing burn patients…..

Doc, you described the fluid requirement in the first 24 hrs, what happens in the next 24 hrs? How do we calculate the fluid requirements for that?

One more question- you gave a few formulas for the burn calculation, could you outline some more?

Surya, N Delhi, India

The formula for fluid resuscitation help to calculate the fluid requirements for the first 24 hours. It is during this period that the critical fluid displacements and loss occur. Loss of body fluids from the burn surface area as well as the leaking of intravascular fluids into the extracellular spaces account for the fluid loss that occur in burn patients. However the body regains its capacity to maintain its intravascular volume by avoiding the leaking of plasma proteins and in fact by the 2^nd 24 hours after the burn, the fluids from the extra vascular spaces start getting reabsorbed. Therefore at this stage it is not necessary to administer a lot of fluids as we do in the first 24 hours. During the second 24 hours the fluids are calculated from the normal daily requirements as any surgical patient and additional fluids are given to maintain the clinical parameters like the pulse, blood pressure and urine output (half ml/kg/hr in adults and one ml/kg/hr in children) as outlined in a previous post.

Some formulas advice cutting down the fluids to be administered in the 2^nd 24 hours to half that of the first 24 hours. This again is a guideline and one must not forget that the resuscitation process is a continuous process and no sudden changes must be attempted in fluid administered which must be very gradually reduced depending on the clinical parameters and patient response unless the patient is in shock or with volume overload.

The parkland formula has been described before in detail. Some of the other resuscitation formulas which were not mentioned in our previous articles are outlined below:

Resuscitation Formulas in burn patients

Formula	Fluid in First 24 Hours	Crystalloid in 2nd  24-Hours	Colloid in 2nd  24-Hours
Brooke (Yowler, 2000)	RL at 1.5 mL/kg per percentage burn, colloid at 0.5 mL/kg per percentage burn, - add  2000 mL D5W	50% of first 24-hour volume - add  2000 mL D5W	50% of first 24-hour volume
Modified Brooke	RL at 2 mL/kg per percentage burn
Evans (Yowler, 2000)	NS at 1 mL/kg per percentage burn, 2000 mL D5W*, and colloid at 1 mL/kg per percentage burn	50% of first 24-hour volume and add 2000 mL D5W	50% of first 24-hour volume
Monafo hypertonic Demling	250 mEq/L saline titrated to urine output at 30 mL/h, dextran 40 in NS at 2 mL/kg/h for 8 hours, RL titrated to urine output at 30 mL/h, and fresh frozen plasma 0.5 mL/h for 18 hours beginning 8 hours post burn	One-third NS titrated to urine output
Metro Health (Cleveland)	RL solution with 50 mEq sodium bicarbonate per liter at 4 mL/kg per percentage burn	Half NS titrated to urine output	1 U fresh frozen plasma for each liter of half NS used and add  D5W as needed for hypoglycemia
Slater (Yowler, 2000)	RL at 2 L/24 h  and add  fresh frozen plasma at 75 mL/kg/24 h

*D5W is  dextrose 5% with water 

(An original initiative in burn care and education from asktheburnsurgeon++)+

Burns in children……

Fluid resuscitation in pediatric population

Doc, are burns in small children more serious than in adults? Also please tell how does the resuscitation of burn patients differ in adults and in children?

Milnarnake p,

Sri Lanka.

Management of burns in children differs significantly from that in adults. This is because the fluid loss in burns depends on the total body surface area that is burnt and the calculation of the body surface area is different in adults and children. When compared to adults it has been found that children have larger head and smaller thighs. Thus while in adults the head is taken as 9 percent in a newborn or infant it is 20 percent TBSA. Similarly the lower limbs account for 18 percent in adults, however in an infant it accounts for only 13 percent TBSA, since the infant has a smaller limb size compared to adults in proportion to the head. Again the upper limbs account for 9 percent each in adults, but in children this is only eight percent. In adults the front and back of the body or trunk account for 18 percent but in infants it is 20 percent.

Thus in an infant

Head – 20

Both upper limbs – 8x2=16

Both lower limbs 13x2=26

Back of trunk -18-20

Front of trunk – 18-20

This all approximates to about 100 percent

To get the most accurate calculation in children the Lund and Browder chart should be used.

Urine output/hour which is one of the most important clinical parameter in monitoring burn patients should be 1 ml/hr in children as compared to adults (0.5 ml/hr). Children who are over 50 kg should be managed as adults for calculating the fluid requirement. Minor burns in children (less than 10% usually do not need any fluid resuscitation as the body can handle this fluid loss. However children with over 10% burns need fluid resuscitation as compared to adults over 15%. The requirements in children are higher and most centers add maintenance fluids to their resuscitation formula.

It is interesting to note that if the parkland formula as used in adults

 i.e. 4x %TBSA x body weight is used in children, the fluid calculated will be inadequate and therefore a modified parkland formula is used in children-

3 x %TBSA x body wt + daily maintenance fluid requirements

How do we calculate the daily fluid requirement in a child? Here’s a simple method:

First 10 kg- 100ml/kg

Second 10 kg- 50ml/kg

Rest of kgs- 20 ml/hr

This is the total maintenance fluid requirement for 24 hrs and this is divided by 24 or 25 to get the per hour calculation

Imagine a child with 25 kg- what is the maintenance fluid requirement for 24 hrs?

First 10 kg- 100ml/kg i.e.  10x100 =1000ml

Second 10 kg- 50ml/kg i.e. 10 x50= 500ml

Rest of kgs- 20 ml/hr i.e.      5x 20= 100ml

                                      Total = 1600ml for 24 hours

This maintenance fluid should be added to the burn fluid requirement – say for example this 25 kg child had 25 percent TBSA burn

i.e. using parkland formula

3x 25x 25

=1875ml add the maintenance 1600 ml

Total= 3475ml in 24 hrs

Divide by 2= 1738 ml in first 8 hrs or divide this by 8= 217 ml each hr for the first 8 hrs

For the next sixteen hrs the fluid will be 1738/16 i.e. 108ml per hour for the next sixteen hours.

This is only a calculation done as a guideline and should not be rigidly adhered to. We at asktheburnsurgeon are comfortable with the modified parkland formula and the fluid requirements as done above. We also add a small dose of albumin or fresh frozen plasma from the second eight hours to help build up the oncotic pressure that is lowered due to loss of plasma proteins.

Urine output in adult burn patients should be around 0.5ml/kg/hr- 1ml/kg/hr

In children this should be around 1ml/kg/hr

Therefore a 25kg child should produce at least 25 ml urine per hour

While in an adult of 50 kg a urine output of 25-30ml would be just acceptable

The clinical parameters and the urine output per hour should be kept in mind and the fluid requirement can be increased or decreased to maintain all the clinical parameters in the normal range. The monitoring should be done as in adults.

Children are more susceptible to burn shock and therefore IV access should be rapidly obtained. Rarely an interosseus live may be needed when these lines cannot be obtained. Glucose levels should be frequently checked since hepatic glycogen levels are limited in children, and addition of D5 Ringer lactate solution can help in preventing troublesome hypoglycemia.

 (An original initiative in burn care and education from asktheburnsurgeon++)

SEVERE BURNS HAND - THUMB WITH CONTRACTURES...

 Hello,

My daughter who is volunteering in Indonesia sent me a photo yesterday of a little girl with a deformed thumb from an untreated burn injury.  She is asking if anything can be done for the child.

I have attached some pictures.

My daughter writes, "L.. is a little over one year old and the first burn incident happened when she was about 4 months and the second incident happened when she was about 8 months (she rolled into the fire.)"

Can you make a recommendation whether or not surgical intervention would be of benefit to her?

Thanks for you time,

Dr D W

Dear Dr D W
Thanks you very much for your letter,
so sad to see this wonderful child suffer from this burn,
nice to hear your daughter is doing charity work abroad,

L...has a burn which is quite severe,
the burns must have been full thickness and would have needed a skin graft during the time of the burn episode ,
as no addition of tissue was done it healed secondarily causing very severe burn contractures,

presently the contracture is severe as it appears,

its has distorted the thumb joints and if untreated will end in severe deformities in the future and she will  be unable to effectively use the thumb,

she needs surgery which will involve ,

releasing the thumb from its present position and getting it back to its normal position,

once done i think a large area of tissue defect will appear and this may need a thick pad of tissue with skin ( flap cover as it is called in plastic surgery ) rather than a thin skin graft, 

choices of flaps include - radial artery flap, abdominal flap and free flap depending on the expertise available

sometimes if we are lucky we may be able to get away with a skin grafting procedure,(this can be made sure of only at surgery),

we at asktheburnsurgeon hope that this sweet child can be helped somehow to regain back her function ....

with best regards

and wishes

asktheburnsurgeon++

Role of colloids in burn resuscitation...........

Doc, what is the role of albumin in early burn resuscitation? Do we have to give it in all cases?

Jessie p,

Colorado, USA

When a patient suffers a burn injury there is a temporary loss of the integrity of the capillaries as we have discussed before. This loss leads to the leakage of plasma proteins like albumin into the interstitial space.  This loss continues for the first eight hours following which the capillaries start to regain their integrity. Therefore if one were to replace the colloids in the first eight hours they would obviously leak out. It seems reasonable that one may start to replace giving colloids in the 2nd eight hours of the burn.

Different types of colloids may be used for resuscitation in burns: fresh frozen plasma, albumin and Dextran. Fresh frozen plasma is often given at a rate of 0.5ml-1ml/kg %TBSA and has a theoretical advantage - it replaces other plasma proteins besides albumin.

Dextran, another colloid used in burn resuscitation increases capillary blood flow, reduces RBC aggregation and helps to reduce tissue edema though this effect is limited to the time that Dextran is being administered as the body will metabolize it eventually. Dextran is composed of polymerized high molecular weight glucose chains and has double the osmotic pressure of albumin.

Hypertonic saline (180-300 mEq/L) has been used in some centers as it helps to shift extracellular fluids ( third space fluid loss) back into the vascular space by osmosis resulting in a reduction of fluid requirements. However there are some disadvantages: hypernatremia and intracellular fluid depletion can occur and therefore serum sodium levels should be closely monitored and maintained below 160mEq/L.

Albumin which is a regular component of our plasma is a protein that maximally raises the intravascular oncotic pressure. When it is given intravenously fifty percent of it remains intravascular, when compared to other colloid solutions where only twenty to thirty percent remains intravascular. Albumin is often infused as the rate of 0.3-1ml/kg /% burn over 24 hours.

In many centers colloids are added in the 2^nd eight hours though Parkland formula advocates only crystalloids in the first 24 hours.  Colloids help to reduce the fluid load in the first 24 hours and they also help to increase the urine output which often tends to go down during resuscitation. Colloid resuscitation is of great benefit in geriatric patients, major burns (>40%), patients associated with inhalation injury and those with cardiac disorders as it is difficult to resuscitate them with limited fluids and they are constantly in the danger of being overloaded. Fluid infusion should be tapered off after the first 24-32 hrs, when one finds that the patient has been adequately resuscitated. Fluid administration should then be planned on the basis of requirements of albumin (keep>2) and free water requirements (electrolyte free) to counter   irreversible water loss. Free water requirement is estimated as (25% + % burn) x BSA (m²) = ml/hr free water. The maintenance of all the clinical parameters like the urine output at normal levels is critical to the continuation of the resuscitation process to its logical conclusion. Prudent use of fresh frozen plasma and albumin can be very helpful and safe when compared to other colloids in burn resuscitation.

(An original initiative in burn care and education from asktheburnsurgeon++)

Monitoring the burn patient during burn resuscitation….

 Doc, we recently had a patient with 80 percent burns. Though we calculated the fluid loss and replaced it adequately the patient died. Could you tell us why this may have happened?

Sohail k,

Karachi, Pakistan.

Patient with major burns have two major issues that need to be dealt with:

a) Calculating the fluid requirement and replacing it

b) Monitoring the burn patient to know if the fluids replacements are adequate

We have already seen the calculation of fluids requirements in a previous post. We shall have a look at how to monitor burn patients. With fluid replacements there can be two issues- inadequate fluid replacement or fluid overload. If the calculated fluids are less then the patient will end up in shock and deteriorate. If the fluids are over calculated then fluid overload, increased pulmonary complications and increased compartmental pressure will result and finally end in circulatory failure and collapse.

All burn patients must therefore be monitored with great care.  A number of clinical parameters that are commonly used in ICU monitored patients are also applicable here:

Pulse

Temperature

Respiration

Blood pressure

Oxygen saturation

Central venous pressure

 Hourly urine output

These are the most common clinical parameters used. As the body looses fluids from burns and the intravascular pressure falls from the fluids shifts the blood pressure tends to fall. However the human body has a lot of inbuilt mechanisms to control this fall and deceptively maintains the blood pressure by releasing catecholamines or chemicals which will cause contraction of the blood vessels and thereby maintain the blood pressure. The pulse also rises from the pain reaction (tachycardia). The body has a limit till which it can support the blood pressure, once the fluid loss crosses this limit the homeostatic mechanisms will fail and  burn shock will result. The increasing compartmental edema that results in burns can result in an erroneous blood pressure reading. Similarly the vasospasm that occurs in the extremities can lead to incorrect oxygen saturation reading by pulse oxymetry.

Urine output is one of the most important parameters while monitoring the burn patient and this should be 0.5ml (kg/hr) in adults and in children    about 1ml (kg/hr). In most cases if an adequate urine output is maintained one can assured of an adequate fluid resuscitation. Major burn patients will need placement of a urinary catheter to monitor the hourly urine output. The volume status can also be gained from the central venous pressure or CVP. Insertion of a cvp line helps in monitoring this pressure and helps prevent fluid overload in normal patients. However in patients with previous poor cardiac function or in geriatric patients one may need the use of a swan ganz catheter. Similarly diabetic patients and those using long term diuretics and also patients with resuscitation difficulties may benefit from the use of the swan ganz catheter. Pulmonary vasoconstriction may lead to faulty CVP or swan ganz measurements. Maintenance of the acid base balance in the body as seen from the various blood gas measurements and analysis suggest adequate resuscitation. Some patients with cardiac co morbidities may need invasive cardiac monitoring. In these patients one must be careful while increasing the fluid administered and should only be done gradually to maintain adequate urine output (0.5ml/kg/hr adult and 1ml/kg/hr in children).

The requirement of fluid may be higher than calculated in some patient groups. Those patients who have suffered inhalation injury need 30-40%more fluids than suggested by Parkland formula. Patients with electrical burns need more fluids as they have greater underlying tissue damage. Patients undergoing diuretic therapy have prior free water deficits and need more fluids for resuscitation. Patients who have undergone escharotomies and have large open wounds may have higher free water losses that need to be adequately replaced. Patients in whom resuscitation is delayed probably have higher inflammatory response, greater fluid needs and attempts should be made to replace the fluid deficit calculated by Parkland in the immediate resuscitation period without causing hemodynamic failure.

(An original initiative in burn care and education from asktheburnsurgeon++)

Factors affecting the depth of the burn………

Doc, besides actually looking and evaluating the burn area is there other ways of knowing that the burn area might be deep?

Marjorie A, Sidney, Australia

A number of factors should be considered while evaluating the burn depth- temperature at which the burn is caused, duration of contact, cause of burn and site of burn.

The area which is burnt is also important as the skin thickness varies at different sites (from 1 mm in the genitalia and eyelids to 5 mm in palms and soles).  The skin is relatively thinner in children and geriatric patients and therefore they tend to suffer a greater degree of burns.

Contact burns tend to be deeper since the burning object or the hot object like the exhaust of a motorcycle remains in direct contact and causes more damage to the skin.

 It must be noted that the lesser the duration of the burn, the lesser the degree of burn. Therefore it is recommended that the burn area be cooled at the earliest. Pouring cold water over burns areas works on this principle and one must within seconds carry out this maneuver to avoid severe burns. The home kitchen is one area where burns often occur. Fortunately water is always available in the kitchen and therefore quickly pouring cold or tap water over the burn area works wonders and one should let the cold water run over the burn area for a few minutes.

Application of oil or mint preparations as is often done by lay people should be avoided as oil stops the heat loss from the surface causing more damage and mint just gives cools the mind and not the burn area.

The cause of the burn should be inquired into as different modes of burns can cause different depths of burns. For e.g. hot water burns are less deep than hot frying pan oils, as the temperatures of hot oil touch 175-200 degrees compared to hot water which may be 75-100 degrees. Different acids and bases can cause different degree of burns depending on their strengths. Thus knowing the burn agent helps a lot in deciding the depth of the burn and predicting the outcome.

 We shall discuss how the monitor burn patients in our next post....

(An original initiative in burn care and education from asktheburnsurgeon++)

Resuscitation Fluids and formulae……….

Doc, how much fluids should be given to a burn patient and can a person survive if fluids are given if the patient comes to the hospital many hours after the burn incident?

Shawn, California

As we discussed in an earlier post, burn wounds loose body fluids from the wound surface as the skin integrity is damaged. Greater the surface area of the burn, more the fluid loss. In general the body is able to tackle the fluid loss that occurs from a less than 15 percent TBSA (total burn surface area) in an adult, and less than 10 percent TBSA in a child. Beyond this the body’s internal mechanisms are unable to handle this loss and the patient will end up in shock if the lost body fluids are not replaced. Once we understand this concept then we are faced with two questions:

a) At what rate should we administer the intravenous fluids?

b) What is the type of fluid that we should administer?

Parkland formula

Charles Baxter from parkland hospital (Texas, USA) made a large contribution to the management of burns by his studies on the fluid loss in burns and their replacement. He observed that the first 24 hours were critical to the survival of burn patients and the replacement of fluids was to be done in the first 24 hours itself. In this the first 8 hours were crucial as the blood vessels and capillaries lost their integrity totally and therefore the intravascular fluids leaked out on a large scale. In the second 8 hours after the burn the capillaries regained their integrity and the leaks were controlled to a great extent. Keeping this in mind Charles Baxter suggested a fluid resuscitation formula in burn patients at 4 ml/kg/TBSA for the first 24 hours. The type of fluid suggested was Ringer Lactate.  Of the total fluid calculated for 24 hours, half of the volume was to be given in the first 8 hours and the rest in the next sixteen hours. 

Why did Baxter suggest Ringer Lactate as the resuscitation fluid?

  Obviously because he observed that it was more physiological and had many advantages:

a) Ringer lactate has a lower sodium concentration (130mEq/L) than normal saline. 
b)The metabolized lactate had a buffering effect on associated metabolic acidosis in burns. 
c)Ringer lactate is an Isotonic crystalloid solution
 

Example for fluid calculation:

Let’s take an example here – a patient with a body weight of 65 kg  comes to the ER with flame burns of 45 percent TBSA.

TBSA 45%

Weight of the patient- 65 kg

Therefore the fluid calculation by parkland formula-

4x% TBSA x body weight

i.e. 4 x 45 x 65

i.e.  11,700 ml for 24 hours

Half of this has to be given in the first 8 hours

i.e. half of 11,700 – which is 5850 ml for 8 hours

Therefore for each hour in the first 8 hours the patient needs 5850/8 ie 731.25 ml or approximately 730ml per hour

For the next 16 hours the remaining 11700 ml needs to be spread out

So 5850/16 is 365 ml needs to be given each hour for the next 16 hours

Thus the patient must receive 730 ml per hour for the first 8 hours post burn and for the remaining 16 hours of the first day the patient must receive 365 ml per hour. 

Coming to the second part of the question- the fluid calculated has to be replaced in the time specified. However some patients appear later than the time of the burn and therefore the fluids which were not administered will have to be replaced at a higher rate but taking care to see that we do not overload the patient and put him into cardiac failure or pulmonary edema.

It must be noted that the calculation of fluids by this formula is only a guide line and a number of factors must be taken into consideration which administering fluids which we shall discuss in another post …..

(An original initiative in burn care and education from asktheburnsurgeon++)

Classification of burns...........

Doc, are there different ways to classify burns?

Mrs. Janice Parker. S. Africa.

Yes there are different ways to classify burns, but the whole purpose is to help in managing them in a better way.  Every burn must be mentioned by its degree or depth since it lets the surgeon know whether he should manage the patient conservatively or by surgery. Further classifying burns in major, minor or moderate helps to decide the level of management that they need. Thus a third degree burn even if it is one percent TBSA (total burn surface area) cannot be managed conservatively and will need surgery. Again a 5 percent TBSA can be managed on an outpatient basis, but a 50 percent TBSA will definitely need inpatient management.

degree of burns.

Degree of burn actually tells us about the depth of the burn. The burn depth is classified as follows.

a) First degree- superficial burns affecting the epidermis are referred to as first degree burns and are similar to sunburns.

 b) Second degree: both the epidermis and the superficial layer of the dermis are damaged in second degree burns.

c) Third degree burns: these burns affect the full thickness skin and often needs surgical management.

d) Fourth degree burns: these burns affect the full thickness of the skin and the underlying structures like nerves, muscles, tendons, vessels and may extend up to the bone.

We can also classify burns according to their size:

a)Major Burns: these consist of chemical or high voltage electrical burns, Inhalation injury, full thickness burns more than 10% TBSA or burns involving more than 25%TBSA.

b) Moderate Burns: these consist of Superficial or partial thickness burns of trunk, hands, feet, perineum or head involving 15-25% TBSA.

c) Minor Burns:  these consist of Burns not involving the hand, perineum, feet or head and must be less than 15% TBSA.

(An original initiative in burn care and education from asktheburnsurgeon+)

ASSESSMENT OF BURN SURFACE AREA……

Doc, what happens if I calculate the burn area wrongly? Is it really important?

Arthur A, Canada

As we have seen in previous posts the loss of fluid from the skin surface depends on the degree of burns and the area of the burns. One must evaluate the total burn surface area (TBSA) to calculate the fluid requirements. There are different methods of fluid calculation in burns.

a) Rule of nine

The rule of nine works well in adult patients. In this method the body surface is divided into various parts measuring in nines.

Rule of nine

Each arm - 9% TBSA

Head - 9% TBSA

Anterior thorax - 18% TBSA

Posterior thorax - 18% TBSA

Perineum - 1% TBSA

Each leg - 18% TBSA

Any burn surgeon will tell you that more often the burns are so irregularly placed that accurate calculation becomes difficult in different regions of the body. In such cases a simple trick is to use the palm of the hand as a method of calculation. At any age the palm of the hand is approximately 1% and can be used to measure the burn areas.  One must not forget that it is the patient’s hand that is used for the calculation and not the doctor’s. An approximate size of the palm of the patient is considered and the equivalent burn area is estimated. For e.g. lets say the burn area was 5 palm sizes of the patient over the body and lower limbs. Now we can assume that the patient has about 5% burns.

It should be noted that first degree burns do not produce fluid losses and therefore only 2^nd degree burns or more should be used for fluid calculation.

However in children the rule of nine can lead to serious errors as the head and body is larger in TBSA than the limbs and therefore the Lund and Browder charts work out to be more accurate while calculating the fluids to be administered.  The Lund and Browder chart is shown below. 

If the fluid calculation is wrong then the patient will be administered less fluids and this will result in shock or low volume circulatory failure and ultimately may be fatal.  The fluids calculated need to be replaced within a time limit as we shall discuss in the next post. Correct volume replacement and correct timing is what makes the resuscitation of burns patients successful.

(an original initiative in burn care and education from asktheburnsurgeon+)

How burns affect the tissues.....

Doc, could you please explain the cellular and chemical processes that occur when the tissues are burnt?

Rony v, Goa

A number of inflammatory processes both local (at the site of the burn) as well as systemic (in the rest of the body) take place when burns occur which eventually lead to the shifting of fluid from the vascular compartment to the interstitial spaces. Subsequent to the burn a number of cells like Neutrophils, macrophages, and lymphocytes cross over into the burned tissues and start releasing chemical mediators like histamine, serotonin, prostaglandins, kinins, platelet products and complement components. These chemical substances damage the normal blood capillary barrier which leads to an increase in the permeability of the vessels. Intravascular fluids therefore start to leak from the walls of the vessels and this ultimately leads to a decrease of the circulating intravascular blood volume. A fact that is not commonly recognized is that these processes that occur in the burn tissues also take place in the tissues that have not suffered any burns and therefore one can see edema in areas of the body that have not suffered burns. Thermal injury also ends up damaging the cell wall and collagen fibers which in turn lead to inadequacy of the cell wall transport mechanisms and buildup of sodium and water and eventual death of the cell if the fluid imbalances are not immediately corrected. In minor burns such as 10 percent in children and about 15 percent in adults these fluid balances are well adjusted and tolerated and therefore additional fluid replacements are not needed. However in patients with TBSA higher than the one’s mentioned above intravenous fluid resuscitation is needed.

The capillaries begin to regain their functional integrity and the leak eventually gets controlled, but this often takes more than 8 hours post burn. Crystalloids are usually given in the first 8 hours and one’s the integrity of the capillary wall is regained after 8 hours, colloid fluids are started since they will not leak out. Adding colloids also help to reduce the fluid overload that may result of excess of crystalloid infusions. Burn wounds are composed of three zones- a central zone of coagulation or severe tissue damage, a peripheral zone of hyperemia or vasodilatation, and an  intervening zone of stasis or low blood flow (ischaemia). If the fluid imbalances that occur from the fluid shifts as noted above are not corrected on time then these zones can extend and more tissue damage can result explaining the fact that some superficial burns on admission can end up as deep over period of time. This can also happen when burn wounds get infected.

(an original initiative in burn care education from asktheburnsurgeon)

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Burns, fluid therapy, burn management, fluid resuscitation in burns

Doc why is fluid therapy so important in burn patients?

Neeraj,

Pune, India

Till the nineteenth century burn patients had a high mortality rate. Why so many patients died in the early stage of burn treatment remained a mystery till the concept of body fluids in different compartments became clear. The body fluids lie in three different compartments- vascular (within the blood vessels), intracellular (within the cells) and extracellular space (outside the cells and blood vessels). A constant shift of fluids keeps occurring to maintain a balance between these three spaces and they remain in a state of equilibrium.

Among the organs of the body the skin is the largest – about 15% of body weight and roughly 1.7 sq meter in surface area. While the skin has a large number of functions like sensation, physical protection, temperature regulation and others, the function of prevention of fluid loss is critical to the burn management. Skin is made up of two critical components –dermis and epidermis.  Burns damage the integrity of the skin and destroy its ability to manage fluids effectively. A lot of chemical substances are released due to the burn injury which increases the leaking of fluids from the vascular compartment to the extracellular space causing edema or tissue swelling. This edema may be insignificant in small burns but in large burns or burns more than 10 percent in children and 15 percent in adults can lead to   loss of water, albumin, sodium  and red blood cells which can lead to a sudden fall in the vascular space compartment pressure and shock (burn shock)- culminating in death if not properly treated. The larger the TBSA of burn (Total body surface area) the greater the risk of death. The fluid loss need to be calculated correctly and has to be replaced. Some historic events like the coconut groove fires and other mass casualties led researches to understand the importance of fluid management especially in the initial stage of burn management.   

It is believed that every year, 2.5 million Americans sustain a significant burn injury of which about 100,000 are hospitalized, and around 10,000 die. Burn researchers - Underhill and Moore were the first to identify the concept of thermal injury- induced intravascular fluid deficits in the early nineteenth century, followed by Evans who introduced the fluid resuscitation formula in 1952. More than 50 percent of patients with 50% TBSA  or more died in the past and now this mortality has come down to less than 10 percent – all because of the clear understanding of fluid management in burn care. 

 (An original initiative in burn care education from asktheburnsurgeon!!!)

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