Baby Memorial Hospital, Kozhikode, Kerala,
India. PIN: 673004
Abstract
Proper perioperative fluid management is critical to
maintain cardiovascular stability and adequate tissue
perfusion. The volume and composition of fluid should be
adapting to the physiology of the child and compensating for
the peri-operative events. Traditionally physicians were
calculating pediatric maintenance fluid requirements based on
studies conducted on healthy children more than 50 years ago
by Holliday and Segar. But a search of literature failed
to reveal a relevant prospective study critically evaluating
the content and volume of Holliday and Segar prescription. But
off late there has been a major debate and re-evaluation about
this concept because of serious concerns regarding development
of hyponatremia and hyperglycemia. This can result in serious
neurological damage or even death in a sick child. This brief
review is an attempt to explain how the original concept was
formed and what is the current thinking?
Key Words: Peri-operative Fluid Therapy, Pediatric
Original concept
Credit for introducing a systemic approach in calculating both
volume and composition of peri-operative intravenous fluids
goes to Holliday and Segar. In 1957 they have introduced
practical methods for prescribing parenteral fluids based on
the metabolic needs of a child at rest [1]. The caloric
requirement for infants weighing up to 10 kg was 100 kcals/kg,
for children of 10-20 kg, 1000 kcals+50 kcals/kg for each kg
over 10kg and in above 20 kg category, 1500 kcals+20 kcals for
each kg over 20 kg [1]. To establish water requirements,
Holliday and co-workers have taken into consideration the
physiological fluids needed for energy expenditure [3]. For
that it was assumed that under normal circumstances, 1ml of
water is required to metabolize 1 kcal. This includes presumed
insensible losses across skin, respiratory tract
and urinary water. So by correlating the energy requirement
with the corresponding water consumption, Holliday and Segar
introduced 4/2/1 rule for the hourly fluid infusion in the
peri-operative period[1]. In the same study, Holliday and
Segar introduced the concept regarding maintenance electrolyte
composition of peri-operative fluids [1]. The idea for which
was derived from the electrolyte contents in the same volume
of human milk. Based on this, it was recommended that an
intake of 2 meq/100kcals/day of both potassium and chloride
and 3meq/100kcals/day of sodium. So this maintenance fluid and
electrolyte solution resulted in infusion of hypotonic
electrolyte solution. For many decades the fluids prescribed
by the physicians was one-fourth to one-third strength saline
based on this concept [4].
However with reports of critical hyponatraemia or hypoglycemia
emerging, these hypotonic solutions are now considered
suboptimal for pediatric peri-operative use [5,6].
Iatrogenic hyponatremia
It is now clear that the main deterrents for iatrogenic
hyponatraemia are 1) Stress induced secretion of anti diuretic
hormones (ADH). 2) Administration of hypotonic solutions
peri-operatively [7,8]. ADH secretion can result in impaired
ability to excrete free water by increasing resorption in the
distal renal tubules and collecting duct [7,8]. There are many
commercially available glucose containing isotonic solutions
which have technically limited sodium content. But these
solutions will be soon converted to be hypotonic as soon as
glucose is transported intracellular and metabolized [8]. In
order to safe guard against overhydration and hyponatremia
many authors have suggested to restrict administration of
postoperative fluids by 33-50% in view of stress induced ADH
response [9,10]. If not child can easily go for over hydration
and hyponatraemia. In a recent editorial, Karen Choong
et al attributed iatrogenic hyponatraemia to maintenance
solution tonicity rather than to volume [11]. Hyponatraemia if
not detected and corrected can result in cerebral oedema,
brain stem herniation or even death. In comparison to adults,
children are more prone to acute encephalopathy probably
because of their bigger brain size with respect to skull size
[12].
Should we give glucose supplementation?
In pediatric patients, hypoglycemia can cause devastating
effects especially in the setting of hypoxia with serious
neural injuries [13]. There is also practical considerations
of detecting hypoglycemia in an anesthetized child. So routine
administration of dextrose was considered as a standard
practice once. On the other hand, risk of perioperative
hyperglycemia was underestimated at that time. Intraoperative
administration of 5% dextrose for prevention of hypoglycemia
will result in hyperglycemia due to stress induced insulin
resistance [14]. Hyperglycemia can also result in osmotic
diuresis, electrolyte disturbances, dehydration, impaired cell
function and even cell death [3]. So taking into consideration
these contradictory views, there was a complete re-evaluation
on this concept.
Presently the well accepted compromise between avoiding
hypoglycemia and hyperglycemia is to use isotonic fluids with
lower glucose concentration (1-2.5%) [15]. There are also
certain situations wherein glucose supplementation is
recommended. These are children with high risk of developing
hypoglycemia as in preterm neonates, children receiving
hyperalimentation, patients with mitochondrial diseases and
those with endocrinopathies [16]. Other than these special
circumstances, routine dextrose administration is now no
longer advised for healthy children receiving anaesthesia even
in neonatal period [17].
Do we need to correct fasting deficit?
It was presumed that as a result of fasting, child may develop
pre-operative fluid deficits secondary to continuing
insensible losses and urine output. So to correct this
deficit, a fluid formula was put forwarded by Furman et al
[18]. It was proposed to calculate the fluid needs by
multiplying the hourly fluid requirement rate, as dictated by
the Holliday and Segar method with the hours of fasting [18].
This was further simplified by Berry et al by 25ml/kg for
children 3 years and younger and 15 ml/kg for children 4 years
and older [19]. The basic assumption in both these fluid
guidelines is that children were fasting for at least 6-8
hours. But with new fasting guidelines by American society of
Anaesthesiologists (ASA), which allow children to have clear
fluids up to 2 hours before surgery, dehydration secondary to
nil per oral (NPO) status has become less relevant [20]. But
despite these, occasionally children may still present for
surgery with prolonged fast. This can result in significant
volume deficits especially in sick children. Correcting fluid
status in such situations should be based on clinical and
laboratory evidence of dehydration and electrolyte imbalances.
But most paediatric anaesthesiologists will agree that even
after 4-6 hours of fast, older infants and children usually do
not have any evidence of volume compromise.
Summary
An appropriate solution for pediatric intraoperative use
should have sodium content close to physiological range. For
half a century content and volume was based on Holliday and
Segar recommendation. But use of hypotonic solution with 5%
dextrose added is found to result in serious hyponatremia,
hypoglycemia or even death in a sick child. Because of these
concerns, current thinking favors use of isotonic solutions
with a glucose requirement of 1-2.5%. For a healthy child
following ASA guidelines of fasting dehydration becomes an
unlikely event.
References
1. Holliday MA, Segar WE.The maintanence need for water in
parenteral fluid therapy.Pediatrics 1957; 19:823-32.
2. Moritz ML, Ayus JC. Prevention of hospital acquired
hyponatremia: A case for using isotonic saline. Pediatrics.
2003; 111:227-30.
3. Ann G. Bailey, Peggy P. McNaull, Edmund Jooste, Jay B
Tuchman. Perioperative Cystalloid and Colloid Fluid Management
in Children: Where are we and how did we get here? Pediatric
Anaesthesiology 2010; 110:375-89.
4. Isabelle Murat, Dubois M. Perioperative fluid therapy in
paediatrics. Pediatr Anesth. 2008;18:363-70.
5. Choog K, Kho ME, Menon K, Bohn D. Hypotonic versus isotonic
saline in hospitalised children: a systemic review. Arch Dis
Child 2006;91:828-835.
6. Robert Sumpelmann, Karin Becke, Peter Crean, Martin Johr,
Per-Arne Lonnqvist et al. European consensus statement for
intraoperative fluid therapy in children. Eur J
Anaesthesilogy2011;28:637-9.
7. Arieff AI. Post operative hyponatraemic encephalopathy
following elective surgery in children Pediatric Anaesthesia
1998; 8:1-4.
8. Per-Arne Lonnqvist. Inappropriate perioperative fluid
management in children: time for a solution? Pediatric
Anaesthesia 2007; 17:203-05.
9. Holliday M, Segar W. Reducing errors in fluid management.
Pediatrics 2003;111:424-5.
10. Paut O, Lacroix F. Recent developments in the
perioperative fluid management for the paediatric patient.
Curr Opin Anaesthesiol 2006; 19:268-77.
11. Karen Choong, Sarah Mc Nab.IV fluid choices in
children:have we found the solution? J Pediatr 2015; 9:5407-9.
12. Moritz ML, Ayus JC. Lacrosse Encephalitis in children. N
Eng. J Med 2001;345:148-9.
13. Inder T. How low can I go? The impact of hypoglycaemia on
the immature brain. Pediatrics. 2008; 122:440-1.
14. Wellborn LG,McGill WA,Hannallah RS et al. Perioperative
blood glucose concentrations in pediatric
outpatients.Anesthesiology 1986;65:543-7.
15. Murat I, Dubois M. Perioperative fluid therapy in
paediatrics. Paediatr Anaesth. 2008;18:363-70.
16. Nishina K, Mikawa K, Maekawa N, Asano M, Obara H. Effects
of exogenous intravenous glucose and lipid homeostasis in
anesthetized infants. Anesthesiology. 1995;83:258-63.
17. Virendra K Arya. Basics of fluid and blood transfusion
therapy in paediatric surgical patients. Indian J Anaesth.
2012; 56:454-62.
18. Furman E, Roman DG, Lemmer LA, Jairabet J, Jasinska M,
Laver MB. Specific therapy in water, electrolyte and blood
volume replacement during pediatric surgery. Anesthesiology.
1975;42:187-93.
19. Berry F. Practical aspects of fluid and electrolyte
therapy. Berry F, editor. Anesthetic management of difficult
and routine pediatric patients. New York:Churchill
Livingstone; 1986.pp.107-35.
20. ASA Task force on preoperative fasting. Practice guidlines
for preoperative fasting and the use of pharmacological agents
to reduce risk of pulmonary aspiration: application to healthy
patients undergoing elective procedure. Anaesthesiology.
1999;90:896-905.