Fluid and Electrolyte Balance Objectives PEDIATRIC FLUID AND ELECTROLYTE BALANCE AND DEHYDRATION FLUID AND ELECTROLYTE BALANCE IN CHILDREN

Fluid and Electrolyte Balance Objectives PEDIATRIC FLUID AND ELECTROLYTE BALANCE AND DEHYDRATION Mary Fran Hazinski, RN, MSN, FAAN, FAHA Professor, Va...
Author: Lewis Whitehead
3 downloads 3 Views 4MB Size
Fluid and Electrolyte Balance Objectives PEDIATRIC FLUID AND ELECTROLYTE BALANCE AND DEHYDRATION Mary Fran Hazinski, RN, MSN, FAAN, FAHA Professor, Vanderbilt University School of Nursing Nashville, Tennessee

At the end of the presentation the participant will be able to:   

Describe the normal distribution of body water and factors causing free water shift into and out of the vascular space Describe calculation of estimated fluid requirements using body weight and body surface area Describe the management of sodium and potassium imbalances

© Mary Fran Hazinski: Please do not reproduce without permission

© Mary Fran Hazinski

FLUID AND ELECTROLYTE BALANCE IN CHILDREN

For further information see

Distribution of Body Water  Calculation of Fluid Requirements  Electrolyte Imbalances 

From: Hazinski, MF (Ed)., Nursing Care of the Critically Ill Child, edition 3, Saint Louis, 2012, Mosby/Elsevier. © Mary Fran Hazinski

FLUID AND ELECTROLYTE BALANCE IN CHILDREN Distribution of Body Water  Calculation of Fluid Requirements  Electrolyte Imbalances 

© Mary Fran Hazinski

TOTAL BODY WATER Location Beyond 6 Weeks of Age EXTRACELLULAR 33%

8% VASCULAR SPACE © Mary Fran Hazinski

25% INTERSTITIAL SPACE

INTRACELLULAR 67%

67% CELLULAR SPACE

© Mary Fran Hazinski from Roberts KE. Fluid, electrolyte and endocrine problems, In Hazinski MF (Ed), Nursing Care of the Critically Ill Child, edition 3. Saint Louis, 2012, Mosby

1

From Guyton, Textbook of Physiology

© Mary Fran Hazinski From Guyton, Textbook of Physiology

© Mary Fran Hazinski

EXTRAVASCULAR FLUID SHIFT

INTRAVASCULAR FLUID SHIFT

With Acute FALL in Serum Osmolality

With Acute RISE in Serum Osmolality

EXTRACELLULAR

VASCULAR SPACE

INTERSTITIAL SPACE

INTRACELLULAR

CELLULAR SPACE

© Mary Fran Hazinski from Roberts KE. Fluid, electrolyte and endocrine problems, In Hazinski MF (Ed), Nursing Care of the Critically Ill Child, ed. 3. Saint Louis, 2012, Mosby

EXTRACELLULAR

VASCULAR SPACE

INTRACELLULAR

INTERSTITIAL SPACE

CELLULAR SPACE

© Mary Fran Hazinski from Roberts KE. Fluid, electrolyte and endocrine problems, In Hazinski MF (Ed), Nursing Care of the Critically Ill Child, ed. 3. Saint Louis, 2012, Mosby

BRAIN CELL PROTECTION

POTENTIAL BRAIN CELL INJURY

With Intravascular Fluid Shift

With Extravascular Fluid Shift

EXTRACELLULAR

INTRACELLULAR

EXTRACELLULAR

Other Cells

VASCULAR SPACE

INTERSTITIAL SPACE

BRAIN CELLS

© Mary Fran Hazinski from Roberts KE. Fluid, electrolyte and endocrine problems, In Hazinski MF (Ed), Nursing Care of the Critically Ill Child, ed. 3. Saint Louis, 2012, Mosby

INTRACELLULAR

Other Cells

VASCULAR SPACE

INTERSTITIAL SPACE

BRAIN CELLS

© Mary Fran Hazinski from Roberts KE. Fluid, electrolyte and endocrine problems, In Hazinski MF (Ed), Nursing Care of the Critically Ill Child, ed. 3. Saint Louis, 2012, Mosby

2

ESTIMATION OF SERUM OSMOLARITY

ANTIDIURETIC HORMONE (ADH/AVP) Normal Function 

2 x [Na+]

=

_______

+ [Glucose] ÷ 18 =

_______

+ [BUN] ÷ 2.8 NORMAL

_______ 280-295 mOsm/L

= =

Produced in hypothalamus, released by pituitary in response to: - rise in serum osmolality - hypovolemia - hypotension



Increases permeability of renal collecting ducts and distal tubule to water, producing renal water retention, fall in serum osmolality

© Mary Fran Hazinski

© Mary Fran Hazinski

URINE AND SERUM OSMOLALITY Normal and SIADH and CSW

SYNDROME OF INAPPROPRIATE ADH SECRETION (SIADH)    

Na+

High circulating levels of ADH in absence of physiologic stimulus Produces dilutional hyponatremia (water intoxication) Typically urine output is low (< 1 mL/kg/hr) Can be associated with CNS disorders, respiratory disorders, ectopic autonomous ADH secretion



Serum Urine 

500 mOsm/L**

CEREBRAL SALT WASTING SYNDROME Typically develops 2-7 days after CNS injury Probably caused by abnormal secretion of natriuretic peptide  Produces sodium diuresis, volume contraction and hyponatremia  Typically urine output is high

Restrict water intake





Administer isotonic saline





Monitor neurologic status; administer 3% saline if neurologic symptoms develop



Consider diuresis

© Mary Fran Hazinski

260 mOsm/L < 260 mOsm/L

© Mary Fran Hazinski

SYNDROME OF INAPPROPRIATE ADH SECRETION: Management 

1 Low Increased

>1 High Increased



Administer fluids and sodium (aggressive fluid resuscitation)



Monitor neurologic status; administer 3% saline if neurologic symptoms develop



Treatment with high-dose fludrocortisone (0.2-0.4 mg/day) may be effective

© Mary Fran Hazinski

© Mary Fran Hazinski

DIABETES INSIPIDUS (DI) Management

DIABETES INSIPIDUS (DI): Pathophysiology 

Decreased secretion (central/neurogenic) or



Replace urine fluid losses (q 10-15 minutes) plus maintenance fluid requirements



Administer ADH (central/neurogenic)



Monitor electrolyte balance



Identify, treat cause

decreased renal response (nephrogenic)to ADH 

Urine not concentrated by kidneys



Significant water loss in urine can rapidly produce hypovolemia, hemoconcentration



Urine volume high with low urine specific gravity, osmolality and sodium © Mary Fran Hazinski

© Mary Fran Hazinski

Slide courtesy of Dr. Norman Staub, UCSF,

© Mary Fran Hazinski

© Mary Fran Hazinski

4

FLUID AND ELECTROLYTE BALANCE IN CHILDREN Distribution of Body Water  Calculation of Fluid Requirements  Electrolyte Imbalances 

From Winters, RW, The Body Fluids in Pediatrics, 1973, Little Brown

© Mary Fran Hazinski

© Mary Fran Hazinski

© Mary Fran Hazinski

© Mary Fran Hazinski

INTRAVASCULAR VOLUME Assessment Systemic perfusion  Skin turgor, mucous membranes, conjunctiva, fontanelle  Systemic and pulmonary edema  Laboratory data (BUN, serum Na+, serum osmolality, urine specific gravity, possible urine chemistries) 

© Mary Fran Hazinski

© Mary Fran Hazinski

5

© Mary Fran Hazinski

© Mary Fran Hazinski

INTRAVASCULAR VOLUME Factors Influencing Fluid Shifts Absolute volume status  Osmotic gradients (sodium)  Capillary pressure, permeability  Colloid osmotic pressure (proteins) 

© Mary Fran Hazinski

© Mary Fran Hazinski

From Elaine Daily, Bedside Hemodynamic Monitoring, Mosby

Slide courtesy of American Edwards

© Mary Fran Hazinski

© Mary Fran Hazinski

6

DAILY MAINTENANCE FLUID REQUIREMENTS WEIGHT First 72 hrs

DAILY BASE RATE 60-100 ml/kg/day

0-10 kg

100 ml/kg/day

11-20 kg

1000 ml + 50 ml/kg/day for kg 11-20

21-30 kg

1500 ml + 25 ml/kg/day for kg 21-30

© Mary Fran Hazinski

© Mary Fran Hazinski

HOURLY MAINTENANCE FLUID REQUIREMENTS WEIGHT First 10 kg + Second 10 kg + Third 10 kg

HOURLY BASE RATE 4 ml/kg/hour + 2 ml/kg/hour + 1 ml/kg/hour

© Mary Fran Hazinski

© Mary Fran Hazinski

MAINTENANCE FLUID REQUIREMENTS 1500 ml/m2 body surface area (BSA)/day  Insensible water losses: 300-400 ml/m2 BSA/day 

Formula to estimate BSA: (4 X kg wt) + 7 = m2 BSA 90 + (kg wt) © Mary Fran Hazinski

FLUID ADMINISTRATION RATE Tailoring Fluid Administration 

Consider clinical condition



Potential increased requirements for dehydration, phototherapy (non LED bililight)



Fever increases IWL 0.42 ml/kg/hr/o C > 37o C



Once patient euvolemic, reduce intake for: congestive heart failure, respiratory failure, renal failure or increased intracranial pressure © Mary Fran Hazinski

7

© Frank Netter

© Mary Fran Hazinski

© Mary Fran Hazinski

FLUID AND ELECTROLYTE BALANCE IN CHILDREN Distribution of Body Water  Calculation of Fluid Requirements  Electrolyte Imbalances 

© Mary Fran Hazinski

HYPONATREMIA Potential Causes Sodium loss  Adrenocortical hyperplasia  Water intoxication  SIADH  Severe hyperglycemia 

© Mary Fran Hazinski From Guyton, Textbook of Physiology

EXTRAVASCULAR FLUID SHIFT With Acute FALL in Serum Osmolality EXTRACELLULAR

VASCULAR SPACE © Mary Fran Hazinski

INTERSTITIAL SPACE

INTRACELLULAR

CELLULAR SPACE

© Mary Fran Hazinski from Roberts KE. Fluid, electrolyte and endocrine problems, In Hazinski MF (Ed), Nursing Care of the Critically Ill Child, ed. 3. Saint Louis, 2012, Mosby

8

Correction of Sodium for Hyperglycemia For every 100 mg/dl rise in glucose above normal, expect serum sodium to fall 1.6 mEq below 135 mEq/L  When serum glucose falls, serum sodium should rise proportionately 

HYPONATREMIA Management Administer sodium or eliminate free water or both  Calculate estimated deficit (use 0.5 below for women) and replace  Correct hyponatremia at rate of 0.5 mEq/L/hour or 10-12 mEq/L/day  Monitor neurologic status; administer 3% saline if needed (3-5 ml/kg, 513 mEq/L) 

© Mary Fran Hazinski

© Mary Fran Hazinski

HYPERNATREMIA Potential Causes

INTRAVASCULAR FLUID SHIFT With Acute RISE in Serum Osmolality EXTRACELLULAR



Salt gain



Free water loss



Diabetes insipidus

VASCULAR SPACE

INTRACELLULAR

INTERSTITIAL SPACE

CELLULAR SPACE

© Mary Fran Hazinski from Roberts KE. Fluid, electrolyte and endocrine problems, In Hazinski MF (Ed), Nursing Care of the Critically Ill Child, ed. 3. Saint Louis, 2012, Mosby

© Mary Fran Hazinski

EXTRAVASCULAR FLUID SHIFT With Acute FALL in Serum Osmolality EXTRACELLULAR

VASCULAR SPACE

INTERSTITIAL SPACE

INTRACELLULAR

CELLULAR SPACE

© Mary Fran Hazinski from Roberts KE. Fluid, electrolyte and endocrine problems, In Hazinski MF (Ed), Nursing Care of the Critically Ill Child, ed. 3. Saint Louis, 2012, Mosby

From Guyton, Textbook of Physiology © Mary Fran Hazinski

9

INTRAVASCULAR K+ SHIFT With Acidosis and Fall in Serum pH K+ concentration changes in a direction opposite the pH change H+ K+ H+ K+ H+ K+ H+

K+

H+

H+

H+ K+ H+H+ K+ H+

VASCULAR SPACE

K+

INTRACELLULAR K+ SHIFT With Alkalosis and Rise in Serum pH K+ DECREASES ~ 0.3 mEq/L for every 0.1 unit increase in pH K+

H+

H+

H+ K+ K+

H+ H+

H+

Dilution  Excessive potassium loss renal tubular acidosis hypomagnesemia and renal potassium loss  extrarenal losses  

 

Inadequate potassium administration Alkalosis/rising pH © Mary Fran Hazinski

HYPERKALEMIA Potential Causes Decreased potassium excretion  Excessive potassium administration  Significant hemolysis (tumor lysis syndrome)  Redistribution  Acidosis 

© Mary Fran Hazinski

K+

K+ H+

K+

CELLULAR SPACE

© Mary Fran Hazinski from Roberts KE. Fluid, electrolyte and endocrine problems, In Hazinski MF (Ed), Nursing Care of the Critically Ill Child, ed. 3. Saint Louis, 2012, Mosby

HYPOKALEMIA Potential Causes 

K+

H+

VASCULAR SPACE

CELLULAR SPACE

© Mary Fran Hazinski from Roberts KE. Fluid, electrolyte and endocrine problems, In Hazinski MF (Ed), Nursing Care of the Critically Ill Child, ed. 3. Saint Louis, 2012, Mosby

K+

K+ K+ H+ K+

HYPOKALEMIA Management Administer potassium infusion over 1-3 hours (0.5-1 mEq/kg)  Monitor ECG (U wave, arrhythmias)  Consider central IV administration  Label IV tubing  Consider addition to daily intake 

© Mary Fran Hazinski

08:23am: 16 year-old patient with end-stage renal failure with complaint of weakness after missing last dialysis appointment. Patient alert,talking; weak, BP=80/55 mmHg. Case details and slide courtesy of Richard Cummins, MD University of Washington, Seattle, WA

© Mary Fran Hazinski

10

HYPERKALEMIC ECG CHANGES: Peaked T waves, Flattened or absent P waves, Prolonged P-R, Prolonged QRS, “Sine wave”, VT, VF

• 08:27am : now 4 minutes later. Why such marked improvement?

Slide courtesy of Richard O. Cummins, MD, Seattle

Slide courtesy Richard O. Cummins, MD, Seattle

O8:23 08:27

(continuous strip)

O8:27

Rx??

© Mary Fran Hazinski

• 08:31am: final strip; 8 minutes from start. • What is full regimen for this problem?

© Mary Fran Hazinski

Slide courtesy of Richard O. Cummins, MD, Seattle

HYPERKALEMIA Management Stabilize Excitable Tissues: CaCl or Ca Gluconate  Shift K+ Into Cells: Sodium bicarbonate, Glucose + insulin, Beta-agonist (albuterol)  Remove K+ From Body: Furosemide, Cation exchange resins, Dialysis Note: Low level evidence (chiefly small case series) supports recommendations 

O8:31 am

© Mary Fran Hazinski

© Mary Fran Hazinski

Hyper- and Hypoglycemia Infants have high glucose needs and low glycogen stores, so can rapidly become hypoglycemic  Hyperglycemia associated with worse neurologic outcome in children  Glucose control in critically-ill adults associated with reduced mortality; hypoglycemia also problematic 

© Mary Fran Hazinski

© Mary Fran Hazinski

11

Glycemic Control in Children

Intensive insulin therapy for pediatric intensive care, Vlasselaers et al, Lancet 2009

Recent publications 

 

© Mary Fran Hazinski

Hirshberg EL, Sward KA, Faustino EVS, Nadkarni VM, Agus MSD, Morris AH, Lacroix J. Clinical equipoise regarding glycemic control: a survey of pediatric intensivist perceptions, Pediatr Crit Care Med 2013; 14:0-0 (published online ahead of print). Tofil NM, Prabhakaran P. Glucose—more data, still no answers (editorial). Pediatr Crit Care Med 2013; 14:1:111-112. Ulate KP. A critical appraisal of Vlasselaers D, Milants I, Desmet L et al: intensive insulin therapy for patients in paediatric intensive care: a prospective, randomized controlled study. Lancet 2009; 373:547-556. Pediatr Crit Care Med 2011; 12:455-458.

© Mary Fran Hazinski

Vlasselears, Lancet, 2009

FLUID AND ELECTROLYTE BALANCE IN CHILDREN

Conclusions   



Hyperglycemia is common in children requiring mechanical ventilation and/or vasoactive infusions Hyperglycemia is independently associated with mortality Glycemic control in many pediatric critical care units maintains serum glucose < 150 mg/dL but not as low as fasting serum glucose. More data needed

Distribution of Body Water  Calculation of Fluid Requirements  Electrolyte Imbalances  Dehydration 

© Mary Fran Hazinski

© Mary Fran Hazinski

DEHYDRATION

MILD ISOTONIC DEHYDRATION

Definitions and Classifications

Clinical Description

Definition: Total output of all fluids and electrolytes exceeds intake  Classified by severity: mild, moderate, severe  Classified by effect on serum sodium: 

hypotonic/hyponatremic isotonic  hypertonic/hypernatremic  

© Mary Fran Hazinski

Eyes sunken, mucous membranes dry Tachycardic but BLOOD PRESSURE AND RESPIRATORY RATE NORMAL  Child irritable, ill  5% Weight loss or less (3% in adolescents)  Estimated 50 ml/kg fluid deficit  

© Mary Fran Hazinski

12

MODERATE ISOTONIC DEHYDRATION: Clinical Presentation Signs of peripheral circulatory failure present (cool extremities, decreased urine output) but BLOOD PRESSURE NORMAL  5-10% Weight loss (4-7% in adolescent)  Estimated 100 ml/kg deficit 

SEVERE ISOTONIC DEHYDRATION: Clinical Presentation DECOMPENSATED SHOCK PRESENT, including hypotension  Child appears moribund  > 10 % Weight loss (> 7% in adolescent)  Estimated 150 ml/kg fluid deficit 

© Mary Fran Hazinski

© Mary Fran Hazinski

ISOTONIC DEHYDRATION

HYPOTONIC DEHYDRATION

Pathophysiology and Management Priorities

Pathophysiology and Management Priorities

Loss of sodium proportional to loss of water so serum sodium normal  Fluid loss proportional from all compartments  Clinical signs as described  Replace deficit while giving maintenance fluids and maintaining electrolyte balance over 24-48 hours 

  

 

© Mary Fran Hazinski

Loss of sodium > loss of water Serum sodium < 125-130 mEq/L Fluid loss predominantly from intravascular compartment so clinical signs worse for any fluid deficit (severe signs with moderate deficit) Fluid resuscitation often necessary Replace deficit over 24 hours (50% first 8 hrs)

© Mary Fran Hazinski

HYPERTONIC DEHYDRATION Pathophysiology and Management Priorities

EXTRAVASCULAR FLUID SHIFT With Acute FALL in Serum Osmolality EXTRACELLULAR

INTRACELLULAR

  



VASCULAR SPACE

INTERSTITIAL SPACE

CELLULAR SPACE

© Mary Fran Hazinski from Roberts KE. Fluid, electrolyte and endocrine problems, In Hazinski MF (Ed), Nursing Care of the Critically Ill Child, ed. 3. Saint Louis, 2012, Mosby

Loss of water > loss of sodium Serum sodium > 150-155 mEq/L Fluid loss predominantly from extravascular compartment so clinical signs less severe despite significant fluid deficit (moderate signs despite severe deficit) Replace deficit over 48 hours--prevent rapid fall in serum sodium concentration © Mary Fran Hazinski

13

INTRAVASCULAR FLUID SHIFT

EXTRAVASCULAR FLUID SHIFT

With Acute RISE in Serum Osmolality

With Acute FALL in Serum Osmolality

EXTRACELLULAR

VASCULAR SPACE

INTRACELLULAR

INTERSTITIAL SPACE

EXTRACELLULAR

CELLULAR SPACE

© Mary Fran Hazinski from Roberts KE. Fluid, electrolyte and endocrine problems, In Hazinski MF (Ed), Nursing Care of the Critically Ill Child, ed. 3. Saint Louis, 2012, Mosby

VASCULAR SPACE

Summary  Questions 

© Mary Fran Hazinski

© Mary Fran Hazinski

Website for Hazinski MF, Nursing Care of Critically Ill Child, ed 3

References  

http://portals.elsevier.com/portal/hazinski 

This custom website provides 20% discount and free shipping





© Mary Fran Hazinski

CELLULAR SPACE

FLUID AND ELECTROLYTE BALANCE AND DEHYDRATION

Principles of Therapy Achieve, maintain IV/IO access  Support systemic perfusion  Replace volume deficit  Administer maintenance fluids  Replace ongoing losses  Restore, maintain electrolyte balance  Monitor organ system function

INTERSTITIAL SPACE

© Mary Fran Hazinski from Roberts KE. Fluid, electrolyte and endocrine problems, In Hazinski MF (Ed), Nursing Care of the Critically Ill Child, ed. 3. Saint Louis, 2012, Mosby

PEDIATRIC DEHYDRATION 

INTRACELLULAR

Blaney, F. Renal problems. In In Hazinski MF (Ed), Nursing Care of the Critically Ill Child, ed 3, Saint Louis, 2012, Mosby. Choong K, Kho ME, Menon K, Bohn D. Hypotonic versus isotonic saline in hospitalized children: a systematic review. Arch Dis Child, 91:828-835, 2006. Levin DL. Cerebral edema in diabetic ketoacidosis. Pediatr Crit Care Med 2008;9(3): 320-329. Roberts K. Fluid, electrolyte and endocrine problems. In Hazinski MF (Ed), Nursing Care of the Critically Ill Child, ed 3, Saint Louis, 2013, Mosby. See, also, articles on glycemic control cited in section regarding serum glucose.

© Mary Fran Hazinski

14

Diabetic Ketoacidosis Cerebral Edema Diagnostic Criteria Abnormal motor, verbal response to pain Decorticate or decerebrate posture  Cranial nerve palsy (esp III, IV, VI)  Abnormal neurogenic respiratory pattern  Major criteria:  

  

Altered mentation, fluctuating LOC Sustained HR deceleration (>20/min)not associated with improvement Age-inappropriate incontinence Levin, 2009 from Muir, 2004

ANION GAP Definition: Difference between positivelycharged ions (Na+ and K+) and negativelycharged ions (Cl- and NaHCO3-) GAP = { [Na+] + [K+]} -- { [Cl-] + [HCO3 -]}  Normal gap = 10-12 mEq/L  Lactic acidosis associated with shock produces an increased anion gap 

© Mary Fran Hazinski

15

Suggest Documents