IV Fluids

Determine HOW you want to give the patient fluids:

• IV bolus?

• Maintenance fluids?

• Fluid Replacement from GI/Urinary/CSF losses?

Once you decide HOW you want to give IV fluids, then you must choose WHAT TYPE.

IV Bolus: 

• Isotonic fluids

• for fluid resuscitation needs

• Monitor for signs of fluid overload after a IV bolus - pulmonary edema, hepatomegaly, volume status

Lactated Ringer (LR)

• Fluid composition below, but note sodium composition and less acidic pH 

• Now recommended in pediatric sepsis guidelines, and ongoing clinical trial looking at buffered fluids vs saline in pediatric sepsis  - study protocol here

• Administer for first line fluid resuscitation in sepsis, hypovolemic shock, hypotension 

• Can not run in the same IV as many drugs (compatibility issues)

Normal Saline (NS)

• Fluid composition below, but note sodium composition and more acidic pH 

• NS is still indicated in liver patients (no lactate), DKA (no studies in peds with LR, and sodium is 130 mEq, hypotonic compared to human plasma sodium), and TBI (want more sodium for hyperosmolar effects, thus NS with 154mEq of Na)

  • • • NS is still widely used due to its easy accessibility, high compatibility with other medications, and low cost 

PlasmaLyte 

• Balance crystalloid solution resembling  human plasma, see fluid composition below

• Expensive $$$, not widely used in peds …yet! 

Maintenance Fluids (mIVF)

• Calculate with the  Holiday-Segar method to calculate

• Definition: IV fluid that replaces the ongoing daily losess of water and electolytes from physiological processes (sweat, respirations, stool, urine, and insensibles) 

• Typically isotonic fluids - NS, LR

• mIVF can contain dextrose

  • • • Infants under 2months of age typically need 10% Dextrose fluid if NPO

• Can calculate a glucose infusion rate (GIR)- the rate of carbohydrates administered to the patients

  • • • this is age dependent

      • neonates and infants typically need 4-8 mg/kg/min

      • Healthy children < 4 mg/kg/min

      • If has high metabolic demands or on TPN, will need higher GIR

• can run up to 12.5% Dextrose fluids peripherally 

Hypoglycemia

• essentially give 25-50g of glucose for blood glucose < 50-60 mg/dL

• If working patient up, grab "critical labs" listed below

• Will need to calculate GIR to understand current glycemic needs

• Acute Treatment of Hypoglycemia:

  • • • • Peripheral line: give D5NS @ 10 ml/kg or D10W @ 5 ml/kg

        • Central line: give D25W @ 2 ml/kg or D50W @ 1 ml/kg (emergency, code dosing)

Metabolic Acidosis

• pH < 7.40

• To determine the type of metabolic acidosis, calculate the  the anion gap: Na+ - (Cl- + HCO3-)

  • • • normal anion gap 8-12 mEq/L

      • If elevated, manes there are unmeasured ions in blood

• Treatment:

  • • • TREAT THE UNDERLYING PROBLEM 

      • Sodium bicarbonate is not the answer to acidosis - it is a temporary fix UNLESS the cause of acidosis is due to ongoing bicarbonate loses

        • • • • • Learn more about sodium bicarbonate here

      • Servere cases causes hemodynamic instablity can be an indication for dialysis 

Dysnatremias

• Serum sodium abnormalities can develop in critical illness 

• 3 common Dysnatremias:

1. DI: Can either be central (pituitary does not secrete ADH) or nephrogenic (kidney receptors do not recognize ADH) and so free water is lost in urine, but sodium is reabsorbed by kidneys, leading to hypernatremia and volume depletion. Central is more common and is often seen after certain brain tumor resections (ex craniopharyngiomas), after severe brain injuries, or due to other pituitary issues.

• Common clinical sign is UOP > 4ml/kg/hr.

• Evaluation:  serum Osm, RFP, UA, and urine Osm/electrolytes

• Treatment: IV vasopressin, DDAVP

2. SIADH: The body secretes an inappropriate amount of ADH so the kidneys retain excess free water leading to hyponatremia and fluid overload. This is seen in many types of critical illness -- especially CNS and pulmonary infections. It is important to diagnose this because these patients can have low UOP, but giving fluid boluses will just make them more fluid overloaded and can worsen hyponatremia.

• Treatment: water restriction, diuresis

3. CSW: Controversial but can occur following neurosurgery or other neurologic insult. In these patients, excessive sodium is excreted by the kidneys leading to hyponatremia and volume depletion as excessive free water is also lost. 

• Treatment: sodium repletion

• Correct sodium slowly (typically by 10-12 mEq over 24 hours) to prevent cerebral edema or central pontine myelinolysis. 

  • • • • An exception to this rule is for seizures secondary to hyponatremia -- GIVE 3% sodium chloride (3-5 mL/kg)

        • 5 mL/kg of hypertonic 3% saline will generally raise the serum sodium by 5 mEq/L

Hyperkalemia 

• Typically  K> 6.0

• Causes: hemolysis, cell lysis, cell injury/crush injury, renal failure, toxic ingestion, aldosterone deficiency (adrenal insufficiency), medication side effect (spironolactone)

• Symptoms: peaked T waves eventually devolving into wide complex QRS arrhythmias and then cardiac arrest 

• Treatment: 

  1. Calcium Chloride/Calcium Gluconate to stabilize cardiac myocytes

  2. IV insulin bolus = 0.1units/kg, max 10 units ALONG WITH  0.5g/kg of glucose (D10 or D25)

  3. Sodium Bicarbonate (1mEq/kg)

  4. Loop Diuretics 

  5. Nebulized Albuterol 

  6. Hemodialysis 

Electrolyte Repletion

• Critically ill patients often have electrolyte disturbances and these should be replaced as needed.

• Goals:

  • • K >4

    • Mg > 2

    • Phos > 4 (many will tolerate lower values

    • iCal > 1.2 for neonates, 1.1 for everyone else

• Clinical Pearls:

  • •  KCl has more potassium, KPhos has more phosphate

    • Low magnesium can impair both potassium and calcium repletion, so consider checking a magnesium level/replete it if <2 prior to giving other replacements if you are having to give frequent replacements.

Nutrition 

• In addition to glucose (discussed above) other elements of nutrition are essential such as fats, proteins (amino acids)

• Increased energy vs decreased energy needs based on illness

• Typical Energy Needs (non- cardiac patients)

  • • • •  Term Infant                             90‐120 kcal/kg/day

        • 1‐3 yrs                                       75‐90  kcal/kg/day

        • 4‐6 yrs                                       65‐75  kcal/kg/day

        • 7‐10 yrs                                     55‐75  kcal/kg/day

        • 11‐18 yrs                                   40‐45  kcal/kg/day

        • >18 yrs                                      20‐35  kcal/kg/day

• Protein (Amino Acid) Needs

  • • • • <1 yr                                            2‐4 g/kg/day

        • 1‐10 yrs                                     1‐1.2 g/kg/day

        • Adolescent                               0.8‐0.9 g/kg/day

        • > 1 yr Critically ill               1.5 times normal

• Lipids (Fat) Needs

  • • • • Typically start 0.5‐1g/kg/day and can increase to maximum of 3g/kg/day

• Pediatric Critically Ill Nutrition Guidelines/Recommendations

  • • • • RBC Intranet has PICU-specific protocols, look there

        • ASPEN Guidelines

        • ESPNIC Guidelines 

• Nutrition Options 

  • • TPN - higher osmolarity so need to be given with central access

      • • also given with lipids

    • PPN - lower osmolarity so can be given via peripheral IV

      • • also given with lipids

    • Enteral Feeds

      • • NG feeds, Post Pyloric feeds (ND, NJ, GJ etc)

• Prefer to start enteral nutrition over parenteral nutrition 

  • • • • Late Parenteral Nutrition maybe superior than Early Parenteral Nutrition - SOURCE

        • Early Enteral Nutrition was associated with better clinical outcomes - SOURCE 

• Vasoactives and enteral nutrition

  • • • • Generally we do not feed patients on vasoactives  due to risk of hypoperfusion to guy via splanchic vasoconstriction 

        • However, if patients are on stable, low doses of a single vasoactive, and overall are hemodynamically intact, can considering feeding

• Non-Invasive Positive Pressure Ventilation (NIPPV) and enteral nutrition

  • • • • In acutely ill patients on NIPPV, enteral feeds are held and they are kept NPO

        • Patients who are recovering from illness or have neuromuscular disease and will be on NIPPV for extended periods of time, can consider gastic vs post-pyloric feeds 

Acute Liver Failure

• Pediatric acute liver failure (PALF) is a diverse, quickly progressing syndrome that accounts for about 8%-15% of pediatric liver transplants in the US.

  • • • < 8 weeks of onset

      • Common causes: Tylenol overdose, medication side-effects, infection (usually viral), metabolic, immunologic, and unfortunately, often idiopathic

      • Work Up: RFP, HFP, Ammonia, Coagulation study, CBC, GGT, lipase, Factor V level, type + screen, liver US with dopplers, may need liver biopsy/MRI after this

      • Complications:      

o   CNS – cerebral edema, hepatic encephalopathy, intracranial hypertension

o   CV – hypovolemia, hypotension, cardiac dysfunction

o   RESP: pulmonary edema, pulmonary hemorrhage, ARDS

o   FEN/GI: GI bleeding, hypoglycemia, hyperammonemia, alkalosis, acidosis, hyponatremia, hypokalemia, hypoMg, hypoCa, hypoPhos

o   RENAL: AKI, hepatorenal syndrome

o   ENDO: adrenal insufficiency,

o   HEME: coagulopathy, DIC, factor levels

o   ID: hyperinflammation, SIRS, and at risk for Gram + and Gram – invasive infection

• Hepatic Encephalopathy is important to categorizing degree of liver failure and has potential ramifications on transplant implications