An Approach to Fluid Management in Paediatrics

Topics / Paediatrics / Fluids and Electrolytes

Summary This article attempts to summarize paediatric fluid management in a more practical manner. We begin by learning how to assess a dehydrated child using descriptive terms such as mild, moderate or severe dehydration. We touch on what basic investigations we need to perform and on how to manage the patient. We used the R-R-M-O method and end the article with some examples.

Basics

When I was a student, I really struggled to understand pediatric fluid management in a practical way. The other issue is that there are different “methods” to approach this topic and I will try to highlight some important differences. Antibiotics are not routinely used, and if given for a systemic infection they should preferably be given parenterally. Some of the patients that will benefit from antibiotic use: Dysentery, cholera, typhoid, and patients with severe acute malnutrition (SAM). Patients may also benefit from other supplements, such as Zinc. This article will focus on fluid management, for the management of acute diarrheal disease read the following article here.

Assessment

The patient should be examined from top to bottom to assess for signs of dehydration and shock. In this state of shock, the patient will have a depletion of fluids from the intravascular space. While in dehydration, there is a reduction in total body water, mainly affecting the intracellular fluid compartment. This usually occurs when the patient has lost more fluids (due to vomiting, diarrhea) compared to their fluid intake. One should also remember that this loss of fluid will also result in an electrolyte imbalance which may also need to be corrected. Keep in mind that when the child is malnourished, the assessment of dehydration is much more difficult and some findings are less reliable.

Starting from the top:

Check the fontanelles: Are they sunken?
Check the eyes: Are they sunken? Is the child producing tears?
Check the mouth: Is the mucosa dry, or moist?
Check the hands: Is the capillary refill < 2 seconds, is there a tachycardia (check brachial pulse if needed), blood pressure?
Check the abdomen: Is there good skin turgor?
Check the “nappy”: Is there adequate urine output? Is there loose stools in the nappies?
Check the heel: Is the capillary refill < 2 seconds?

The following are signs of shock:

Delayed capillary refill time > 3 seconds
Rapid, weak pulse rate
Cool peripheries
Decreased level of consciousness
Hypotension
Decreased pulse volume

Degree of dehydration
Classification
	Mild	Moderate	Severe
Infant	5%	10%	>15%
Adolescent	3%	6%	>9%
Infants and young children	Thirst, ALERT, restless	Thirsty, LETHARGIC, irritable	DROWSY, COMATOSE, cold
Older Children	Thirsty, alert	Thirsty, alert (usually)	Usually alert (but may be reduced), cold
Signs and Symptoms
Fontanel	Normal	Slightly depressed	Sunken
Eyes	Normal	Sunken	Markedly Sunken
Tears	Present	Present or Absent	Absent
Mucous membranes	Moist	Dry	Very Dry
Cutaneous perfusion	Normal	Normal	Reduced, Mottled
Tachycardia	Absent	Present	Present
Palpable pulses	Present	Present (weak)	Decreased
Blood pressure	Normal	Orthostatic hypotension (difficult to assess)	Hypotension
Skin turgor	Normal	Slight reduction	Reduced
Urine output	Normal	Oliguria	Anuria and severe oliguria

This is a very detailed classification, and it includes common findings that assist in the classification of dehydration. It is very important to learn how to classify the patient as this will help you manage the patient later. The EML guidelines simplify this process by dividing the patient into two, instead of three. This classification goes as follows:

1. Severe dehydration: These patients have sunken eyes, very decreased skin turgor (skin pinch lasts ≥ 2 seconds) and they also drink poorly

2. Some dehydration: These patients have sunken eyes, decreased skin turgor (skin pinch < 2 seconds) and they drink eagerly, but they are also irritable/restless.

So it seems like this is a more simpler way to assess a dehydrated patient. However, I prefer to use the classification described above: mild, moderate, severe dehydration.

Investigations

The investigations done will depend on the severity of the illness

Formal Blood: Infective markers, electrolytes
Blood gas, helps to correct acute electrolyte imbalances and acid-base disturbances
HIV status, remember to request for consent
Urinalysis: leucocytes, nitrites and blood
Stool culture: If one suspect dysentery, typhoid or cholera

Management

It is important to keep in mind that these patients need frequent re-assessment. You perform an initial assessment and then you keep re-assessing the patient at certain intervals. For instance, if the patient is in shock, the EML guidelines advices a continuous re-assessments. While if the patient is not in shock but remains dehydrated, then the patient should be monitored at 4-hourly intervals.

What to monitor at every assessment:

State of hydration
Blood glucose
Review blood electrolytes and correct
Review acid-base status and correct
Urine output should be > 1ml/kg/hour – however, keep in mind that urine output measurements may be difficult to assess in smaller children due to various reasons.
Daily weight measurements or measuring the weight at 6 hourly intervals may assist with the hydration status in smaller children
Assess child’s ability to continue oral feeds: If the child is severely dehydrate or in shock one may without feeding the child until stable. Otherwise, one should always promote oral hydration either with breastmilk (if the child is breastfed) with/without the addition of oral rehydration solution (ORS).

Keep in mind that children who are malnourished should not be given too much IV fluids as this may cause more harm than good. This is because children with severe malnutrition have poor cardiac reserve.

Step 1: Resuscitation

Here, you want to replenish the intravascular space with fluid to improve perfusion to the organs.

The first problem we must address is hypovolemic shock.
Fluid of choice according to the EML guidelines: Normal Saline
Route: First attempt should be with intravenous, but if you cannot manage to get intravenous access within the first 5 minutes one should set up an intra-osseous infusion.
The patient should be given boluses of fluids: This is calculated as 20ml/kg boluses, then you re-assess the patient’s clinical condition. You may repeat these boluses around three (3) times, however, by the time you are giving the third bolus this patient should be taken to ICU for more intensive management (CVP, Inotropic support). One should also monitor the patient for fluid overload (respiratory distress, increased liver span, gallop rhythm) after each bolus.
If the patient has severe malnutrition, reduce the dose of each bolus to 10ml/kg and administer it over a period of 10minutes. In this case, you may give up to four (4) boluses but as above, further treatment should be done in ICU. These patient’s may deteriorate due to septicemia and fluid overload.
Keep in mind that IV boluses is technically when you set up the IV line to be “open”. While an IV push is when you give a medication/fluids very rapidly over a period of 30 seconds. Be careful with giving too much fluid over a short period of time eg IV push.
Only once shock has been managed, then proceed to the next step.

Step 2: Rehydration

Here you want to replace the fluid that the child has already lost, called the fluid deficit. This fluid needs to cover the patient water, electrolyte and energy needs. Hence, the fluid of choice is Oral Rehydration Solution or half Darrows/Dextrose 5% (half DD).

The EML approach:

I am going to cover this here because as a student I always struggle to correlate the EML with my lecture notes or books. The EML approach provides a more simpler approach, and it provides a more general rate/hour for fluids. However, the concepts for the management patient remain the same.

If the child WAS not in shock AND has not failed oral hydration, provide the child with oral rehydration solution. Alternatively, a nasogastric tube may also be used at a reduced dose.
If the child WAS in shock AND/OR has failed oral hydration, then provide the patient fluids via an intravenous line.
1. Fluid of choice according to the EML guidelines: For oral fluids (ORS) and if IV (half Darrows/Dextrose 5%
2. Here is where the management differs a little bit. The EML guidelines provide a simpler way to manage the rehydration part.
  1. They state that if the child can take oral fluids, one should give:
    1. PO ORS @ 80ml/kg (20ml/kg/hour) for 4 hours then re-assess or
    2. NGT ORS @20ml/kg for 4 hours then re-assess
  2. They state that if the child cannot take oral fluids, or was in shock, one should give:
    1. IV half Darrows/Dextrose 5% (half DD) @ 10ml/kg/hour for 4 hours then re-assess
  3. Keep in mind that if the child is given ORAL FLUIDS: Give more if the child wants more, teach the caregiver how to continue providing the child fluids, if the child vomits wait for 10minutes and continue more slowly. At any time the child begins to tolerate oral fluids, one should begin ORS at the rate prescribed above. Oral feeding should also begin at normal volumes and times once the child has normal level of consciousness, is not in severe distress, is not in shock and does not have a surgical abdomen.
3. If the child has no dehydration at presentation or the dehydration is resolved after treatment: Show the caregiver how to manage ongoing losses with 10ml/kg after each bowel movement until the diarrhea stops. Homemade sugar salt solution (SSS) may also be used.

The non-EML approach:

This is my preferred approach. Here you manage the patient according to the percentage of dehydration. You need to start by calculating the fluid deficit. This is calculated as: “(the percentage of dehydration multiplied by the weight in kilograms * 1000) – (Any bolus give in Resuscitation)”. For instance, a 5% (0.05) dehydrated; 10kg child has a fluid deficit of [(0.05 x 10 *1000) – (0ml bolus) = 0.5L. Hence, this is 500ml of fluid deficit. We then divide this over a 24 hour period so 500ml/24 = 20.83ml/hour of fluids.

It is important to note that according to the mild-moderate-severe dehydration classification, patients who have mild dehydration may be rehydrated using oral fluids. Patients who have severe dehydration need to be rehydrated using IV fluids. While patients who have moderate dehydration may be rehydrated with oral fluids, this group is just on the border and may also benefit from IV fluids depending on the particular patient. In this situation, the EML’s approach on seeing whether the patient “tolerates oral fluid” or does “not tolerate oral fluids” may help you identify the patient that will require IV fluids.

One additional note to add, according to the book Nelson Essentials of Pediatrics 6^th edition, mild and moderate dehydration will benefit from oral hydration. They also state that children who are mildly dehydrated should receive 50ml/kg ORS over 4 hours. While patients with moderate dehydration should receive around 100ml/kg ORS over 4 hours. Ongoing losses, described below, is then also treated with ORS at 10ml/kg for each stool.

Step 3: Maintenance

Here you want to provide the patient with fluids that will replace the fluid/electrolytes lost due to insensible losses (skin and lungs) and urinary losses. The fluid given usually contains water, electrolytes and glucose. The glucose in this fluid will prevent a state of starvation for the patient and will decrease the chance of developing hypoglycemia. Maintenance fluids are also usually given to patients who are often nil per os (NPO).

The fluid of choice is Oral Rehydration Solution or half Darrows/Dextrose 5% (half DD). The rate at which the fluid is given depends on the body weight of the patient. Due to practical reasons, the patient’s actual body weight is used (instead of the ideal or dry body weight).

Maintenance fluids will not cover fluid loses that are seen “excessive” e.g from lose stools, NGT. These losses will be covered under “ongoing losses” below. Maintenance fluids also provides “too much” fluid in patients with fluid overload, for instance in cases where the patient has impaired kidney function. Therefore patients with anuria due to chronic kidney disease will benefit from an adjusted rate of maintenance fluid.

Most institutions have charts that have a predetermined value for the fluid rate for children who are are neonates, and sometimes for older children. For children that are not neonates, one may easily use the Holliday-Segar Formula for maintenance fluids. This formula is also known as the 4-2-1 rule. It works in the following way: You multiply by x4 the first 10kg of the child, then you multiply by 2 the next 10kg of the child and then you multiply by 1 the weight that remains. This value is the added up and it results in a rate/hour. For instance, a child who is 23kg will require a rate of: (10kg x 4) + (10kg x 2) + (3kg x 1) = 63ml/hour.

In the case that the child’s weight is less than 20kg, you simply multiply the first 10kg by 4, then the remainder of the weight by the next value, which is 2. A child with a weight of 14kg, will require a rate of: (10kg x 4) + (4kg x 2) = 48ml/hour.

Standard Maintenance Fluids
Neonate	Age	Volume(ml/kg/day)
	Day 1	>60
	Day 2	90
	Day 3	120
	Day 4	150
	Day 5+	150 - 180
Infants & Children	< 6 months	150
	6 months - 1 year	120
	1 - 2 years	100
	2 - 4 years	85
	4 - 10 years	70
	> 10 years	2 - 3 liters a day
Kindly note that the volume is given as ml/kg/day, and therefore you will need to divide by 24 to get the volume in ml/hour

Holliday-Segar Formula
Up to 10kg	4ml/kg
10kg - 20kg	40ml + 2ml/kg (for each kg above 10kg)
> 20kg	60ml + 1ml/kg (for each kg above 20kg)

Step 4: Ongoing Losses

In this section, you will replace the ongoing losses. Ideally, the fluid that comes out of the patient should be measured and replaced. For instance, if the patient had a 100ml of fluid drained from a nasogastric tube (NGT), then this 100ml should be replaced. It is a general rule that children should have around 10ml/kg replaced for each lose stool.

Notes:

When to stop: The patient is fully hydrated. The patient develops signs of fluid overload eg periorbital oedema.
When to resume normal diet: Patient should resume normal diet after they have been rehydrated.

Examples

Example 1

An 18 kg child with 10% dehydration, not feeding well and no signs of shock. Requires the following:

Resuscitation: No IV boluses needed
Rehydration [(0.1 x 10 x 1000) – (0ml boluses) ]/24 = 41.66ml/hour
Maintenance: (10 x 4) + (8 + 2) = 24ml/hour
Ongoing Losses: Currently there are no ongoing losses that need to be corrected.

Therefore, we have insert an IV line a setup ½ DD as the fluid of choice @ (41.66+24) 65ml/hour AND we continue to monitor the child around 4 hourly. The next time we see the child, it is reported that the child had a lose stool x1, so we add 10ml x 18 = 180ml to the fluid that needs to be given to the child.

Example 2

A 25kg child with 15% dehydration (has signs of shock), requires the following:

Resuscitation: IV boluses needed to be give, in this example we gave two boluses and the patient responded [(20ml x 25) x 2 ] = 1000ml! Wow! Do you see how much fluid we are giving this child. This is why we should be careful and be cautious with fluid overload. The fluid of choice here being normal saline, then once the patient responds we continue with the IV fluids as rehydration and maintenance but we will be using ½ DD.
Rehydration: [(0.15 x 25 x 1000)- (1000ml)]/24 = 114.58ml/hour.
Maintenance: (10 x 4) + (10 x 2) + (5 x 1) = 65ml/hour.
Ongoing losses: Currently there are no ongoing losses that need to be corrected.

Therefore, we have inserted an IV line and already changed the normal saline to ½ DD and set the rate at 114.58+65 = 179.58ml/hour. We then continue to monitor the child and correct any ongoing losses.

References and Further Reading 1. Greenbaum, L., 2022. Maintenance Fluids and Replacement Fluids in Children. [online] Cancer Therapy Advisor. Available at: [Accessed 17 September 2022].
2. Georgopoulos, G. and Novak, C., 2022. [online] Pedscases.com. Available at: [Accessed 17 September 2022].
3. Jefferies, C. and Bhopal, S., 2022. Paediatric IV Fluid Prescribing | Geeky Medics. [online] Geeky Medics. Available at: [Accessed 17 September 2022].
4. Drip Hydration Mobile IV Therapy | NAD, Dehydration, Hangover, Flu, Myers Cocktail. 2022. IV Bolus Vs Push: What's The Difference And Which Do You Need?. [online] Available at: [Accessed 17 September 2022].

Published on September 14, 2022

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