Docstoc

Fluid and Electrolyte Emergencies in Critically Ill Children

Document Sample
Fluid and Electrolyte Emergencies in Critically Ill Children Powered By Docstoc
					Fluid & Electrolyte Emergencies
         In Critically Ill


         Dr.Patibandla.Sowjanya
  Dept Of Accident , Emergency & Critical Care Medicine
 Vinayaka Missions Kirupanandavariyar Medical College




                                           A&E(VINAYAKA)
        Introduction

• Total body water (60%)
• Two third is intracellular fluid (40%)
• One third is extra cellular fluid (20%)
  - Interstitial fluid (15%)
  - Intravascular fluid (5%)



                                  A&E(VINAYAKA)
Fluid shifts



                           EXTRACELLULAR
INTRACELLULAR 30 LIT
        40%
                       INTERSTITIAL 9 LIT
                                          IV 5 LIT
                             15%
                                            5%


                                        A&E(VINAYAKA)
Electrolyte Components
mEq/L          ICF     ECF
                      Plasma     Interstitial
   Na+          15       142
                        142          144
   K+           150
               150        4           4
  Ca2+           2        5          2.5
  Mg2+          27        3          1.5

  Cl-           1      103             114
  HCO3-         10      27              30
  HPO42-       100      2               2
  SO42-         20      1               1
Organic acid     -      5               5
                               A&E(VINAYAKA)
 Protein        63      16              6
               ICF         ECF

Major Cation   Potassium   Sodium
               Magnesium

Major Anion    Phosphate   Chloride
               Sulphate    Bicarbonate
               Protein


                                A&E(VINAYAKA)
   Osmolarity
 Measurement of the total solutes in a water solution per
  liter.
 Osmolarity = [sodiumx2 ]+urea/2.8+glucose/18
 Serum osmolarity is 280-300 mOsm/L
 280-300 mOsmol/L- Isotonic
 > 300 mOsmol/L – Hypertonic
 < 280 mOsmol/L - Hypotonic
                                           A&E(VINAYAKA)
       Three categories of fluids

• Isotonic - Fluid has the same
 osmolarity as plasma
 Eg: Normal saline
     Ringers lactate



                             A&E(VINAYAKA)
• Hypotonic - Fluid has fewer solutes
  than plasma

Eg : Water, 1/2 N/S (0.45% NaCl)



                             A&E(VINAYAKA)
• Hypertonic - Fluid has more
 solutes than plasma

 Eg:5% Dextrose in Normal Saline
 (D5 N/S) , 3% saline solution.


                       A&E(VINAYAKA)
                   Isotonic
                   Infusion


                          2 litres of
                            blood




30 litres   9 litres          3 litres




                       A&E(VINAYAKA)
        Intravascular Volume increases to 5 liters




30 litres               9 litres           5 litres




                                   A&E(VINAYAKA)
                       Hypertonic
                        Infusion


                          2 litres of
                            colloid




30 litres   9 litres          3 litres




                        A&E(VINAYAKA)
     Initially it becomes 5 L




30 litres             9 litres           5 litres




                                 A&E(VINAYAKA)
Hypertonicity of Colloid shifts I/C fluid into I/V




     29 litres                 8 litres              7 litres




                                            A&E(VINAYAKA)
 If 2 L of Crystalloid infused…


                                      2 litres of
                                      0.9% saline




30 litres                9 litres         3 litres




                                    A&E(VINAYAKA)
Initially I/V becomes 5L




30 litres                  9 litres           5 litres




                                      A&E(VINAYAKA)
Isotonicity of Crystalloid shifts I/C & I/V volume into interstitial space




           29 litres                     10.5 litres              4.5 litres


                                                         A&E(VINAYAKA)
               Hypotonic
                Infusion


                        2 litres of
                        5%dextrose




30 litres   9 litres         3 litres




                       A&E(VINAYAKA)
Hypotonicity Shifts the fluid into the I/C space




31 litres                 9.7               3.3
                                            litres
                          litres

                                       A&E(VINAYAKA)
        Signs of Volume depletion

•   Postural hypotension
•   Tachycardia
•   Absence of JVP
•   Dry mucosa
•   Decreased skin turgor
•   Oliguria
                              A&E(VINAYAKA)
    Signs of Volume overload
•   Hypertension
•   Raised JVP/gallop
•   Pedal edema
•   Pulmonary edema
•   Ascites
•   Organ failure

                        A&E(VINAYAKA)
Basic principles of fluid therapy
            Abnormal loss: GIT, 3rd
Replace     space,Ongoing loss, septic and
            Hypovolemic shock

Maintain    Insensible water loss +
            urine

Repair      Acid base, electrolyte
            imbalances

                               A&E(VINAYAKA)
    The rules of fluid replacement
•   Replace blood with blood
•   Replace plasma with colloid
•   Resuscitate with colloid / crystalloid
•   Replace ECF depletion with saline
•   Rehydrate with dextrose



                                     A&E(VINAYAKA)
Case Scenario
 45 yr old was brought to ER with h/o loose
  stools & vomiting since 2 days

 Drowsy and lethargic with signs of severe
  dehydration, BP-80/50 , PR-120

      What is initial fluid of choice?


                                  A&E(VINAYAKA)
• Isotonic saline / Ringer’s lactate

• No dextrose containing fluid initially


               Why?

                                   A&E(VINAYAKA)
A&E(VINAYAKA)
               Case Study #1
• HPI:
  – A 55 year old man is in the Neuro ICU for acute non
    hemorrhagic stroke.

• Hospital course:
  – Decreasing urine output (< 0.5 ml/kg/hr) over the last 24
    hours.

    What is your differential diagnosis?

     What diagnostic studies would you order?

                                           A&E(VINAYAKA)
               Case Study #1

  Differential diagnosis
Oliguria
  1) Pre-Renal (decreased effective renal blood flow)
     Diminished intravascular volume, cardiac
      dysfunction, vasodilatation
  2) Post-Renal
     Outlet obstruction (intrinsic vs. extrinsic),
      foley catheter occlusion
  3) Renal
     Acute tubular necrosis, acute renal failure,
      SIADH, ...
                                               A&E(VINAYAKA)
                 Case Study #1

        Laboratory studies
Serum studies
Sodium 120 mEq/L            BUN 4 mg/dL
Chloride 98 mEq/L           Creatinine 0.4 mg/dL
Potassium 3.7 mEq/L    Glucose 129 mg/dL
Bicarbonate 25 mEq/L        Osmolality 260 mosmol/kg
Urine studies
Specific gravity 1.025  Sodium 58 mEq/L
Osmolality 645 mosmol/kg

What are the primary abnormalities?



                                      A&E(VINAYAKA)
                         Case Study #1

               Laboratory studies

Major abnormalities
 1) Hyponatremia
 2) Oliguria (inappropriately concentrated urine)




 What is the most likely explanation for these
  findings?


                                               A&E(VINAYAKA)
In Hyponatremia……




                A&E(VINAYAKA)
                       Case Study #1

Syndrome of Inappropriate Antidiuretic Hormone
                  (SIADH)
  Variable etiology
     ▪ Trauma
     ▪ Infection
     ▪ Psychosis
     ▪ Malignancy
     ▪ Medications
     ▪ Diabetic ketoacidosis
     ▪ CNS disorders
     ▪ Positive pressure ventilation
     ▪ “Stress”
                                       A&E(VINAYAKA)
                     SIADH
 By definition, “inappropriate” implies having excluded normal
  physiologic reasons for release of ADH:

  ▪ 1) In response to hypertonicity.

  ▪ 2) In response to life threatening hypotension.

 Hyponatremia

 Oliguria

 Concentrated urine

  ▪ elevated urine specific gravity

  ▪ “inappropriately” high urine osmolality in face of hyponatremia

 Normal to high urine sodium excretion

                                                 A&E(VINAYAKA)
                     Case Study #1

                     SIADH
• Diagnosis
  – Critical level of suspicion.
  – Demonstration of inappropriately concentrated urine in
    face of hyponatremia
           urineosmolality,  SG,  urine
           sodium excretion
  – Be certain to exclude normal physiologic release of ADH



                                          A&E(VINAYAKA)
                       Case Study #1

                       SIADH
• Treatment
 – Fluid restriction
 – Avoid hypotonic fluids
 – Hypertonic saline / oral sodium chloride
 – Frusemide.




                                          A&E(VINAYAKA)
   Cerebral Salt wasting Syndrome

• Development of excessive natriuresis with
  hyponatremic dehydration in patients with
  intracranial disease
• Seen in Head injury, Brain tumor,
  Intracranial Surgery or stroke



                                   A&E(VINAYAKA)
                           CSW vs SIADH
features             CSW              SIADH
Volume status        Low              Normal
Wt                   Loss             No change
Orthostatic signs    Present          Absent
Sr Na                Decreased        Decreased
Hematocrit           Increased        Normal
Uric acid            Normal or inc    Decreased
Resp to hydration    Improvement      Dec Na
Resp to fluid rest   Possible shock   improve
Urine Na             >100             >20
                                       A&E(VINAYAKA)
                   Case Study #1

      The saga continues….
Hospital course:
    Four hours after beginning fluid restriction, you are
    called because the patient is having a generalized
    seizure. There is no response to two doses of IV
    lorazepam and a loading dose of fosphenytoin


What is the most likely explanation?



                                          A&E(VINAYAKA)
                          Case Study #1

               The saga continues
Seizure
  1) Worsening hyponatremia
  2) Intracranial event
  3) Meningitis
  4) Other electrolyte disturbance
  5) Medication
  6) Hypertension

What diagnostic studies would you order?
                                           A&E(VINAYAKA)
                     Case Study #1

             The saga continues
Stat labs:
  Sodium 110 mEq/L




What would you do now?




                                     A&E(VINAYAKA)
                       Case Study #1

          Hyponatremic seizure
• Treatment
   – Hypertonic saline (3% NaCl) infusion

   – To correct sodium to 125 mEq/L, the deficit is equal to
          0.6 X weight[kg] X (125 - measured sodium)


            0.6 X 60 X (125-110)      = 54O mEq




                                              A&E(VINAYAKA)
                    Newer method
• Rate of infusion of 3%NaCl       = Na Requirement x 1000
                                       infusate sodium x time
•                      (Desired-Actual Na) x 0.6.body wt x 1000
                         513 x no of hours
•   As patient is symptomatic, rate of correction is 1 mEq/hr,
•   Required rate of infusion of 3% NaCl = 1 x 0.6 x 60 x 1000
                                            513 x 1
                                         = 70 ml/hr
•   Check sodium after 4 hours and correct accordingly


                                                A&E(VINAYAKA)
Hyponatremia




A&E(VINAYAKA)
                  Case Study # 2

• 60 year old retired engineer presented to ER with
  history of inability to speak and move all 4 limbs since
  today morning. Detailed history revealed that he has
  been on naturopathy diet since 6 months and had
  developed GTCS 2 days back. He was treated outside
  for GTCS and following the treatment he is unable to
  communicate or use his limbs
                                             A&E(VINAYAKA)
• His previous lab reports showed Na is 117
  mEq/L and rest of the parameters are within
  normal Limits
• Repeat Sodium in our hospital showed 145
  mEq/L

• What could be the possibility?

                                   A&E(VINAYAKA)
     Central Pontine Myelinolysis

• Develops with
 1. Aggressive treatment of Chronic
    hyponatremia
 2. Raising Sr.Na >25mEq/L in first 48 hours
 3. Raising Sr.Na to Normal or Above normal
    in 48 hours


                                   A&E(VINAYAKA)
                      CPM

• Focal demyelination in the Pons &
  extrapontine areas.
• Causes  Mutism / dysarthria
            Spastic Quadriplegia
            Pseudobulbar palsy
            Seizures
            Altered Mental Status
           Coma & Death             A&E(VINAYAKA)
      Principles of Hyponatremia
             Management
• Asymptomatic Hyponatremia Use
  0.9%NaCl
• Symptomatic Hyponatremia Use 3% NaCl
• Correct only 12mEq/L defecit only perday
• Chronic Hypernatremia with severe
  symptoms should receive hypertonic saline
  only to arrest the symptoms and followed by
  slow correction @ 0.5 mEq/L
                                   A&E(VINAYAKA)
Hyponatremia Management is Double Edged Sword



                         Knowledge




         Wisdom



                                     A&E(VINAYAKA)
                 Case Study #3

HPI:
      A 5 month-old girl presents with a one day history of
      irritability and fever. Mother reports three days of “bad”
      vomiting and diarrhea.
Home meds:
      Paracetamol and ibuprofen for fever
PE:
      BP 70/40, HR 200, R 60, T38.3 C. Irritable, sunken eyes
      and fontanelle.

                                              A&E(VINAYAKA)
          Case Study #3



No one can obtain IV access after 15 minutes,
what would you do now?




                                 A&E(VINAYAKA)
                Case Study #3

Place intraosseous line
  Bolus 40 ml/kg of isotonic saline
  Reassessment (HR 170, RR 40, BP 75/40)
Serum studies
  Sodium 164 mEq/L                    BUN 75 mg/dL
  Chloride 139 mEq/L                  Creatinine 3.1 mg/dL
  Potassium 5.5 mEq/L           Glucose 101 mg/dL
  Bicarbonate 12 mEq/L
  pH 7.07   pCO2 11
  pO2 121   HCO3 8

                                                    A&E(VINAYAKA)
          Case Study #3



What is the most likely explanation of this
patient’s Condition?




                                  A&E(VINAYAKA)
                     Case Study #2

   Treatment of Hypernatremia
• To stop ongoing fluid loss
• To correct water deficit
  = plasma Na – 140 x 0.6 x body wt. in kg
         140
• Water deficit can be replaced with water by mouth or IV 5%
  dextrose or 0.45% NaCl




                                             A&E(VINAYAKA)
           Rate Of Correction

• Acute Hypernatremia ½ body water defecit
  in 24 hours
• Chronic Hypernatremia ½ body water
  defecit in 48 hours

• Rapid correction  cerebral edema &
  Neurological deterioration

                                  A&E(VINAYAKA)
              Case Study #4
• HPI:
  – A 50 year old man was involved in a motor vehicle
    accident two days ago. He sustained an isolated head
    injury with intraventricular hemorrhage and multiple
    large cerebral contusions. Three hours ago, he had an
    episode of severe intracranial hypertension (ICP 90mm
    Hg, MAP 50mm Hg, requiring volume plus epinephrine
    infusion for hypotension. Over the last two hours, his
    urine output has increased to 150 - 200 ml/hour

                                         A&E(VINAYAKA)
What is your differential diagnosis?
What test would you order?




                            A&E(VINAYAKA)
                             Case Study #4

            Differential diagnosis
Polyuria
  1) Central diabetes insipidus
     Deficient ADH secretion (idiopathic, trauma, pituitary surgery, hypoxic
     ischemic encephalopathy)

  2) Nephrogenic diabetes insipidus
      Renal resistance to ADH (X-linked hereditary, chronic lithium, hypercalcemia,
     ...)

  3) Primary polydipsia (psychogenic)
     Primary increase in water intake (psychiatric), occasionally hypothalamic
     lesion affecting thirst center

  4) Solute diuresis
     Diuretics (lasix, mannitol,..), glucosuria, high protein diets, post-obstructive
     uropathy, resolving ATN, ….

                                                             A&E(VINAYAKA)
                 Laboratory studies
Serum studies
Sodium 155 mEq/L                  BUN 13 mg/dL

Chloride 114 mEq/L                Creatinine 0.6 mg/dL

Potassium 4.2 mEq/L               Glucose 86 mg/dL

Bicarbonate 22 mEq/L              Serum osmolality: 320 mosmol/kg

Other
Urine specific gravity 1.005, no glucose.

Urine osmolality: 160 mosmol/kg

What are the main abnormalities?
                                                         A&E(VINAYAKA)
                              Case Study #4

                  Laboratory studies
Major abnormalities


  1) Hypernatremia
  2) Polyuria (inappropriately dilute urine)



What is the most likely explanation?




                                               A&E(VINAYAKA)
                               Case Study #4

                  Diabetes Insipidus
Diagnosis

  Central Diabetes insipidus

     1) Polyuria
     2) Inappropriately dilute urine (urine osmolality < serum
     osmolality)

     May be seen with midline defects
     Frequently occurs in brain dead patients



  What should you do to treat this
                                A&E(VINAYAKA)
  patient?
                    Case Study #4

            Diabetes Insipidus
• Treatment
  – ADH preparations - dDAVP nasal spray 2-4 μg/dl
  – Potentiate ADH effect – chlorpropamide,
    carbamazepine, NSAID’s.
  – Increase ADH release – Clofibrate
  Warning
  – Closely monitor for development of hyponatremia



                                         A&E(VINAYAKA)
Hypernatremia




A&E(VINAYAKA)
                Case Study #4
• HPI:
  – An 35 year old lady with Chronic kidney disease presents
    with irritability. She is on nightly peritoneal dialysis at
    home. The lab calls a panic potassium value of 7.1 meq/L.
    The tech says it is not hemolyzed.



What do you do now?


                                                A&E(VINAYAKA)
                        Case Study #4

                  Hyperkalemia

 Treatment


  Immediately repeat serum potassium.
      Do not wait for confirmatory labs especially if ECG
       changes present.



  Anticipatory
      Stop potassium administration including feeds

                                               A&E(VINAYAKA)
                ECG




• What is this rhythm?
• What is your immediate treatment?
                                A&E(VINAYAKA)
                 Case Study #5

            Hyperkalemia
 Control effects
  Antagonism of membrane actions of potassium
    ▪ 10% Calcium gluconate 10-20 ml over 5 -
      10 minutes; may repeat x2

  Shift potassium intracellularly
    ▪ Glucose   1 gm/kg plus 0.1 unit/kg regular
      insulin
    ▪ Alkali therapy - Sodium bicarbonate 1
      mEq/kg IV
    ▪ Inhaled 2 adrenergic agonist
                                     A&E(VINAYAKA)
–Removal of potassium from the body
   –Loop / thiazide diuretics
   –Cation exchange resin: sodium
    polstyrene sulfonate (Kayexelate) 1
    gm/kg PO or PR (or both)
   –Dialysis


                              A&E(VINAYAKA)
A&E(VINAYAKA)
Hyperkalemia R
                x




A&E(VINAYAKA)
                Case Study #5

• HPI:
  – A three year old boy is recovering from septic shock. He
    received 150 ml/kg in fluid boluses in the first 24 hours
    and has anasarca. You begin him on a frusemide infusion
    for diuresis. He develops severe weakness and begins to
    hypoventilate. You notice unifocal premature ventricular
    beats on his cardiac monitor.



                                               A&E(VINAYAKA)
What is your differential diagnosis?
What tests would you order?




                                       A&E(VINAYAKA)
                       Case Study #6

                 Laboratory studies

Serum studies
Sodium 134 mEq/L         BUN 11 mg/dL
Chloride 98 mEq/L        Creatinine 0.4 mg/dL
Potassium 2.4 mEq/L      Calcium 9.2 mg/dL
Bicarbonate 27 mEq/L     Phosphorus 3.2 mg/dL

Other
ECG: Unifocal PVC’s




What is the main abnormality?

                                                A&E(VINAYAKA)
                    Case Study #6

             Laboratory studies
Major abnormality


 1) Hypokalemia


What would you do now?




                                    A&E(VINAYAKA)
                     Case Study #6

                Hypokalemia
 Treatment
   Oral
    ▪ Safest, although solutions may cause
      diarrhea
   IV
    ▪ do not exceed 40 mEq/L or 10 – 20
      mEq/hr potassium.
     - never give inj.Kcl directly
      intravenously.
   Replace magnesium also if low
    ▪ (25-50 mg/kg MgSO4)
                                     A&E(VINAYAKA)
A&E(VINAYAKA)
                   Summary
• Disorders of sodium, water, and potassium regulation are
  common in critically ill.


• Diagnostic approach must be considered carefully for each
  patient


• Strict attention to detail is important in providing safe and
  effective therapy


                                              A&E(VINAYAKA)
A&E(VINAYAKA)

				
DOCUMENT INFO
Shared By:
Categories:
Tags:
Stats:
views:14
posted:1/18/2013
language:Unknown
pages:78