Transcript No Slide Title
FLUID AND ELECTROLYTES DISASTERS
JOSE-MARIE EL-AMM NEPHROLOGY DIVISION WSU/DMC/HUH AUGUST, 2006
COMPOSITION OF BODY FLUID COMPARTMENTS
COMPOSITION OF ECF AND ICF ECF ICF Na K Cl HCO 3 PHOSPHATE 141
4.1
113
26 2.0
10
120-150
3 10
140
(ORGANIC)
TOTAL BODY WATER= 0.6 X TOTAL BODY WEIGHT (0.5 IN THE ELDERLY OR OBESE, 0.7 IN INFANTS AND VERY YOUNG CHILDREN) ¼ IVV ¾ ISV 2/3 ICF 1/3 ECF
(Principal Cells)
CLINICAL APPROACH TO HYPONATREMIA
IS HYPONATREMIA REALLY HYPOTONICITY?
Translocational vs. isotonic WHAT IS THE VOLUME STATUS?
What are the physiological signals to the kidney and the brain WHAT IS THE URINE SODIUM AND OSMOLALITY?
Is ADH present and is it physiologically appropriate
CASE STUDY 1
A 30 year old woman is admitted for an increase in edema and worsening jaundice. She is a known alcoholic and has had several admissions for jaundice and ascites. She stopped taking her diuretic approximately 10 days ago.
Physical examination: blood pressure 128/80, heart rate 76 supine. No orthostatic change in BP noted. She has icteric sclera, ascites, sacral and pedal edema. Her liver span is 10 cm.
Labs: 125 89 bilirubin= 12mg/dL albumin= 2.5 g/Dl 3.2
28 5 80 0.8
U Na = 1mEq/L Uosm= 300mOsm/kg H 2 O What is her Posm? What is her cell size?
CASE STUDY 1
What is her effective arterial volume?
mild volume depletion( 4%) history change in body weight no orthostatic changes BP or pulse moderate volume depletion( 5% to 10%) HR 15/min on standing systolic BP 15mm Hg on standing severe volume depletion( 10%) supine hypotension supine tachycardia
CASE STUDY 1
Is her total body water high, low or normal?
Is her total body sodium high, low or normal?
EDEMA=
INCREASED TOTAL BODY SODIUM AND WATER BUT DOES NOT! NOT! NOT! TELL YOU THE PROPORTIONS (SODIUM CONCENTRATION)
ORTHOSTATIC HYPOTENSION=
DECREASED TOTAL BODY SODIUM AND WATER BUT DOES NOT! NOT! NOT! TELL YOU THE PROPORTIONS (SODIUM CONCENTRATION)
BODY COMPARTMENT VOLUMES
70 kg person 0.6 =42 liters total body water 25 liters intracellular (ICF)-3/5 TBW 28 liters intracellular (ICF)-2/3 TBW 17 liters extracellular (ECF)-2/5 TBW 14 liters extracellular (ECF)-13 TBW 3.5 liters intravascular (IVV)-1/5 ECF 3.5 liters intravascular (IVV)-1/4 ECF 13.5 liters interstitial (ISV)-4/5 ECF 10.5 liters interstitial (ISV)-3/4 ECF
PRINCIPAL SENSORS IN VOLUME REGULATION
EFFECTIVE CIRC VOL
/
/
SYMPATHETIC TONE VENOUS RETURN
/
/
CARDIAC OUTPUT
/
BP BARORECEPTOR STIMULATION
/
/
A II
/
ALDO VENOUS CONSTRICTION/ RELAXATION
/
CARDIAC CONTRACTILITY ARTERIAL CONSTRICTION or RELAXATION
/
RENIN SECRETION
/
TUBULAR Na + REABSORPTION
CASE STUDY 1
Can you tell if ADH is being secreted? How?
Why is her ADH status the way it is?
What turns ADH off?
What turns it on?
CONTROL OF ADH
ADH
ALL NONE P OSM U OSM 280 50 300 1200
CASE STUDY 1
A 30 year old woman is admitted for an increase in edema and worsening jaundice. She is a known alcoholic and has had several admissions for jaundice and ascites. She stopped taking her diuretic approximately 10 days ago.
Physical examination: blood pressure 128/80, heart rate 76 supine. No orthostatic change in BP noted. She has icteric sclera, ascites, sacral and pedal edema. Her liver span is 10 cm.
Labs: 125 89 bilirubin= 12mg/dL albumin= 2.5 g/dL 3.2
28 5 80 0.8
U Na = 1mEq/L Uosm= 300mOsm/kg H 2 O
CASE STUDY 1
Which IV fluids would you select?
CASE STUDY 1
What diuretic(s) would you use?
What would be the most likely or severe complications using diuretics in her case?
(Principal Cells)
CASE STUDY 1
CLARISSA’S TEAM HAVE BEEN WORKING ON HER FOR THE LAST WEEK. WITH ‘JUDICIOUS’ USE OF DIURETICS AND FLUID RESTRICTION, THEY HAVE DROPPED HER WEIGHT BY 12 LBS AND INCREASED HER SODIUM BY 5 MEQ/L. THE ON-CALL CHECK OUT TO YOU IS “DON’T WORRY ABOUT HER.” AT 2 AM YOU ARE CALLED BY THE NURSE BECAUSE CLARISSA’S BP IS 80/60 AND HER HR IS 110/MIN.
WHAT DO YOU DO?
CASE STUDY 1
1. DON’T WORRY ABOUT IT.
2. START AN IV OF NS AT 150CC/HR 3. BOLUS HER WITH NS IN 100CC INCREMENTS UNTIL HER BP INCREASES 4. GIVE 25 GRAMS OF ALBUMIN IVPB 5. START DOPAMINE
CASE STUDY 2
A patient with severe congestive heart failure and massive edema is admitted to the hospital complaining of progressive dyspnea. Laboratory values 125 94 40 4.1 25 2 What is his Posm?
What is his cell size?
CASE STUDY 2
1-Spironolactone is administered but no diuresis occurs despite 2 days of treatment. Why?
2-A thiazide diuretic is then added to spironolactone with equally discouraging results. Why?
3-What single diuretic might result in successful diuresis? Why?
(Principal Cells)
CASE STUDY 2
A loop diuretic is given with better results but still not impressive diuresis What diuretic might you add to the loop diuretic to increase the loop diuretic potency?
CASE STUDY 3
A 60 year old man was evaluated for persistent cough and a 25 pound weight loss over a 3 month period. He smoked a pack a day for 40 years. P.E.: BP sitting 110/70, no signs of dehydration and no evidence of edema.
A pleural effusion is present on the right. PPD was positive.
Weight 65 kg.
CASE STUDY 4
115 88 3.7
24 4 0.6
105 P osm 245 mOsm/kg H 2 O U osm 340 mOsm/kg H 2 O U Na 39 mEq/L
In order to get rid of a water load, one needs to produce very dilute urine. What are the requirements for such urinary dilution?
1)Extrarenal requirements adequate GFR adequate solute delivery 2)Intrarenal requirements intact vasa recta and loop function absence of ADH
CAUSES OF SIADH
Carcinomas (lung, pancreas, duodenum) Pulmonary disease(pneumonia, Tb, abscess, etc.) CNS disorders (meningitis, encephalitis, SDH, SAH, CVA, trauma, etc)
CASE STUDY 4
A 40 year old man is brought to the ER by EMS after a witnessed seizure. His family states that he has been complaining of a severe headache and has had progressive mental deterioration over the last week or 10 days. They say he takes no medications and has no significant medical history.
Physical exam is completely negative except for meningeal signs. There is no focal neurological deficit, no papilledema. He weighs 60 kg. Labs: 110 80 Uosm=275mOsm/kg 3.5
22 U Na =50 mEq/L CSF: 100WBC: 75%mononuclear
CASE STUDY 5
Is ADH present? (hint: look at U osm ) Why is this man hyponatremic?
(present TBW) (present S Na ) =present TBS (normal TBW) (normal S Na ) =normal TBS (0.6)(60kg) x (110) = (???) x (140) (36L)(110)/(140) = (???) = 28L 36 – 28 =
8 liters excess water
SYMPTOMS OF HYPONATREMIA
Mainly neurologic Symptoms of cerebral edema Nausea and malaise followed by headache, lethargy, obtundation, seizures, coma and death The rate at which the hyponatremia develops determines the degree and severity of the symptoms Several protective responses which act to minimize cell swelling Within four hours of hyponatremia developing the cells start to lose solutes & as intracellular solute amount decreases, water moves back out of the cells, returning the cell volumes toward normal
CASE STUDY 5
How would you treat this man?
For rapid correction of symptomatic euvolemic hyponatremia, hypertonic (3%) saline is used Hypertonic (3%) saline has about 0.5mEq/ml.
( 500mEq/L) What are your goals and end points?
Goal for rapid/initial S is lower Na is to increase S Na to 120 125mEq/L or until symptoms improve-whichever Overly rapid correction of hyponatremia can lead to an osmotic demylination state Patients should have plasma serum sodium concentrations increased at less than 12 mEq/L/day (0.5mEq/L/hr)
The amount of sodium needed to raise the serum sodium can be estimated by the
sodium deficit.
deficit per liter.
Multiply the total body water (0.5xlean body weight in kg in women, 0.6x weight in men) by the plasma sodium 36L x 15 mEq/L =
540 mEq Na need
At <0.5mEq/L/hour need to change over 30 hours 1000mL/30hours
30 mL/hour
CASE STUDY 6
A 30 year old man comes in complaining of polyuria and polydipsia for the previous two weeks. He has a history of sarcoidosis diagnosed 10 years ago for which he has been on Prednisone intermittently. Except for bilateral pulmonary crepitants and for uveitis, the physical exam is normal. Labs: 152 120 30 4 25 1.0
U/A: neg glucose, acetone Uosm=75 mOsm/kg H 2 O
What are the causes of polyuria?
1.Diabetes mellitus 2.Diabetes insipidus 3.Hypokalemia
4.Hypercalcemia
5.Psychogenic water drinking
HYPERNATREMIA
BY DEFINITION, HYPERNATREMIA IS A HYPERTONIC STATE. YOU STILL DON’T KNOW THE VOLUME STATUS WITHOUT EXAMINING THE PATIENT. IN A
VOLUME CONTRACTED
STATE, WATER AND SODIUM ARE LOST-JUST MORE WATER THAN SODIUM. IN AN APPARENTLY
EUVOLEMIC
PATIENT, PURE WATER IS LOST. THERE ARE FEW SIGNS OF VOLUME DEPLETION AS MOST OF THE WATER LOSS IS INTRACELLULAR.
VOLUME EXPANDED
STATES ARE THOSE IN WHICH HYPERTONIC VOLUME EXPANSION TAKES PLACE.
CENTRAL DIABETES INSIPIDUS:
Idiopathic Trauma Hypoxic encephalopathy Posthypophysectomy Neoplastic 1 :craniopharyngioma, pinealoma, cyst metastatic: breast, lung Misc: sarcoidosis , aneurysm, Histiocytosis X, encephalitis, meningitis
NEPHROGENIC DIABETES INSIPIDUS:
Hereditary: usually X-linked, very rare AR form Drugs: lithium , cidofovir, foscarnet Electrolyte disorders:
hypokalemia, hypercalcemia
Misc: sickle cell anemia or trait , renal amyloidosis, Sjögren’s syndrome, transient DI in pregnancy
DIABETES INSIPIDUS THERAPY
DDAVP
a 2 amino acid substitute of ADH with potent antidiuretic effect but little to no pressor effects
Mild volume depletion(1-2 kg), a low salt diet and a thiazide diuretic
increases proximal sodium and water resorption and decreases water delivery to the ADH sensitive collecting tubule
Don ’ t use loop diuretics
induce a relative resistance to ADH by decreasing the maximal interstitial concentration
NSAIDs
potentiate ADH and are additive to the thiazide effect(renal prostaglandins oppose ADH effects)
CASE STUDY 7
A 78 year old woman was admitted with right hemiparesis. She had a 9 year history of hypertension.
PE: Her BP was 190/95 mm Hg. Pulse 80 beats per min.
CASE STUDY 7
LABS: Hct 40%. Urine: SpGr 1.025, negative for protein and glucose. Sediment: Occasional WBC and RBC. BUN 17, Creat. 1.0 mg/dl. Glucose 140 mg/dL, Na 140 mEq/L, K 3.7 mEq/L, CO 2 24 mEq/L and Cl 103 mEq/L.
After admission she was managed with tube feedings and eventually transferred to a nursing home.
Three weeks later she was readmitted because of vomiting and tachypnea. PE: Wt. 67 kg., BP 115/80. P=120, Temp. = 101.6
unresponsive and had poor skin turgor.
F. She was LABS Urine: SpGr 1.022, protein 1+, glucose neg. Sediment: Few hyaline casts. BUN 120 mg/dl, creatinine 3 mg/dl, glucose 150 mg/dL, Na 160 mEq/L, K 5.9 mEq/L, Cl 125 mEq/L, CO 2 18 mEq/L. Hct 48%.
CASE STUDY 7
Is total body sodium increased, normal or decreased? It total body water increased, normal or decreased?
How did this occur?
Is total body sodium increased, normal or decreased?
BP 115/80 P=120 Is total body water increased, normal or decreased?
Normal Our patient Water Sodium
poor skin turgor
How did this occur?
Loss of sodium and water-more water than sodium
Water losses:
insensible (temp 101 F), urine ( conc.), GI
Sodium losses:
poor intake and vomiting
THE TRAGEDY OF THE VERY YOUNG & VERY OLD
Mobile people lose salt and water (N/V) but as IVV , ADH and they become thirsty/seek out fluids. fluid intake with ADH present can lead to hyponatremia Non-mobile people (playpens, restraints, strokes) cannot respond to thirst if they lose more water than sodium, they become hypernatremic
CASE STUDY 7
What is the first priority in her therapy?
IVV resuscitation
What IV would you first order?
0.9% NaCl
How much would you give?
Until she is better
CASE STUDY 7
Once she has a stable blood pressure, her total body sodium (TBS) has been returned to normal How much water would be needed to lower her serum sodium to 140 mEq/L?
PE: Wt. 67 kg.
LABS: BUN 120 mg/dl, creatinine 3mg/dl, glucose 150 mg/dL, Na 160 mEq/L, K 5.9 mEq/L, Cl 125 mEq/L, CO 2 18 mEq/L.
67kg x .5=33.5L=
TBW
160 x 33.5=140 x desired TBW desired TBW=38 liters She needs
4.5 liters of water
her serum Na to 140 mEq/L to drop
TREATMENT OF HYPERNATREMIA
Rates of correction should be carefully controlled as cerebral edema can occur with over-rapid corrections. Correcting at less than 0.5mEq/L/hr (12 mEq/day) is safe.
Eg: 5 liters of water need to be given to replace the water deficit.
Serum sodium 165 140mEq/L 25mEq/L This will take 50 hours to drop it less than or equal to 0.5 mEq/hour 5000mL/50hours = 100 mL/hour of D 5 W or 200 mL/hour of D 2 1/2NS