- Jets are used often but the amount varies considerably depending on the type and brand of nebulizer used.
- In pediatrics, like adults, much of the medication is lost during expiration.
More drug is delivered when the volume of diluents is increased.
When administered to intubated infants, the dosages need to be increased due to the reduced deposition.
What will affect Particle characteristics?
Hygroscopic nature of particles.
Viscosity and concentration of the medication.
Velocity the drug (due to the administration device).
What are some affects of Airway anatomy?
The narrower the airway, the greater the deposition.
Neonatal airway is small to start with then add the ET tube, bronchoconstriction, and mucous.
Whitaker believes that the amount that the amount of drug reaching the terminal airways is negligible.
What are some affects of Ventilatory pattern on aerosol deposition?
Best pattern is with laminar flow in a slow deep inspiration with inspiratory pause.
This may be done on a ventilator but is near impossible with a breathing infant.
What are advantages of nebulizers?
Little patient coordination required
Effective in acute respiratory distress, flow, or volume
Ability to give either a large or small volume of aerosol
Drug dosage and/or particle size can be modified
What are disadvantages of nebulizers?
Less easily transported
Cleaning and preparation required
Amount of medication delivered is variable
Provides a medium for bacterial growth.
What are the advantages of MDI?
Efficient drug delivery
Short preparation and delivery time
Particles resist hygroscopic growth
Can be used on newborns/infants
What are the disadvantages of MDI?
Limited choice of drugs and concentrations.
Possible reaction to propellants.
Foreign body aspiration.
What are the advantages of DPI?
Similar to MDI
Limited hand breath coordination needed
Doses easily counted
What are the disadvantages of DPI?
Limited number of drugs
Possible airway irritation
Possible reaction to the carrier powder
Requires high inspiratory flow
Requires loading before use
Less useful in acute obstruction
Can only be used on ages 4+
What is the SPAG and what is it used for?
Designed to deliver Ribavirin for RSV bronchiolitis
Gas-powered jet nebulizer uses three jets
Uses drying chamber to shrink particles
Baffle is sides of container
Aerosolized Ribavirin has generally fallen out of favor as a treatment for RSV.
The exception being patients with chronic respiratory or cardiac anomalies who go on to develop RSV.
New research is looking at Ribavirin as a possible treatment for SARS.
What are the indications for Oxygen Therapy?
Treat and relieve documented hypoxemia
Decrease workload on heart
What are the contradications for Oxygen Therapy?
For Neonates less than 35 weeks gestation, what is expected PaO2 and SpO2?
Pao2 50 - 70 mmHg
Spo2 88 - 95%
For Larger infants and children greater than 35 weeks gestation, what is expected PaO2 and SpO2?
Pao2 > 60 mmHg
Spo2 > 95%
What are the signs of hypoxia in a newborn?
Apnea and/or bradycardia
- Because fetal Hb has increased affinity for 02 the newborn's pa02 may drop to 30-40 torr before cyanosis appears
What are the hazards of Oxygen Therapy in a new born?
What is the GOAL of Oxygen Therapy in a newborn?
Maintain pa02 of 50-80 torr based on the age of the newborn
Pa02 of pa02 of 100 torr may be required for PPHN (persistent pulmonary hypertension in the newborn)
What are common Oxygen Delivery Devices for neonatal and pediatric patients?
What is an Oxygen Hood and when are they used?
delivery device of choice in the preemie for the first days of life.
The oxygen is administered via a heated humidified hood via a blender.
- Both the fi02 and the air temperature must be controlled.
- An O2 analyzer should always be used.
Increased CO2 build up if the flow is too low is a potential hazard
What is an Oxygen Cannula and when are they used?
Newborns, even preemies can be given 02 by nasal cannula.
USED ON PATIENT with chronic oxygen needs or as weaning tool from other modes of delivery.
Because the infant's Ve is so low, the FI02 at a given flow rate differs drastically from the FI02 of adult 02 cannula.
Neonatal flow meters can be calibrated as low as 0.025 lpm.
Estimated FIO2 on the nasal cannula at various flowrates for patients under two years of age:
1/4 Lpm 25%
1/2 Lpm 30%
1 lpm 35%
What is a Mist Text and when are they used, and what is the disadvantage of it?
RARELY USED ANYMORE
Once the infant is old enough to roll over and sit up, he is too big for a O2 hood.
The disadvantage of a mist tent is that the infant will no longer get an exact fi02 inside the croup tent.
The fi02 of the mist tent runs between 21% and 50%, but there is little control because the enclosure is too large for fine-tuning.
Mist tents are more tolerated by the infant, since mom can get in tent to hold them
What is an Oxygen Mask, when are they used, and is it a good choice for oxygen delivery device?
The 02 mask is a poor choice for an infant because it can obstruct his/her airway.
It is a poor choice for the toddler because the child has an instinct to protect his/her face and nose and he/she will pull it off.
At about 3 years of age the child might wear a mask, but the nasal cannula is generally preferred.
Once a child is old enough to tolerate a mask, one has the same choices as with the adult.
As with the adult patient the entrainment mask is the only sure method of exact fi02 delivery because these are high flow systems.
What are the indications for Resuscitation bag?
Delivery of oxygen for short periods.
Delivery of oxygen during initial resuscitation.
FIO2 80-100% when used properly with reservoir.
What is thermoregulation?
The maintenance of equality between the heat dissipation and heat production from the body.
What is themal neutral zone?
When the infant is neither gaining nor loosing heat and the oxygen consumption is its lowest, then balance is achieved.
What is desired Rectal and Skin Temperature?
rectal temperature at 36.5-37.5
skin temperature 36-36.5
What is Internal Thermal Gradient, and what is it regulated by?
The difference in temperature between the warm core of the body and the cool skin
- Regulated by:
The metabolic rate.
The amount of subcutaneous fat.
The body surface area.
The distance from the body core to the skin surface
What is non shivering thermogenesis?
increased heat production due to burning of brown fat
Why do preemies have a difficult time regulating ITG (Internal Thermal Gradient)?
A large amount of skin surface to body weight.
Relatively thin layers of skin.
Low amounts of body fat.
A high metabolic rate and rarely get enough calories to keep them warm
What are the 4 types of heat loss that concerns us in the NICU?
What is Radiant heat loss?
Dissipation of heat to surrounding objects not in direct contact with them
What is Conductive heat loss?
Transfer of heat to cooler surfaces in contact with the infant like wet blankets or cold stethoscope.
What is Convective heat loss?
Loss of heat from the skin to surrounding air. Air currents carry away warm blanket of air around them
What is Evaporative heat loss?
As liquids (urine, sweat) evaporate, they carry away heat
What is Hypothermia in a newborn referred to as and hazards of it?
- Cold Stress:
The initial response to cold stress is vasoconstriction to shunt away from the skin.
- This leads to:
Anaerobic metabolism in shunted areas causing metabolic acidosis.
Pulmonary vasoconstriction and worsens the hypoxemia and acidosis but altering the V/Q ratio.
Hypoxemia, further worsening the response to hypothermia
___________ also triggers nonshivering thermogenesis and fat metabolism to produce heat resulting in further acidosis and hypoglycemia. All of these factors will keep the infant warm for a while. If the cold stress if corrected, the neonate may recover with no harm
___________ produces initial vasodilation to dissipate heat and is soon followed by increased metabolism and oxygen consumption
What cause Hyperthermia?
What is Insensible Water Loss?
Extra cellular fluid makes up 45% of body weight of a term infant vs. 60% of a 32 week infant.
This means that the more premature the infant, the more they are prone to insensible water loss
What are some factors the cause Insensible Water Loss?
Increased motor activity.
Skin break down.
Congenital skin defects.
What is an Isolette?
An Isolette (incubator) is an environmental containment chambers that contains the neonate in a controlled temperature, humidity, and oxygen.
What are the Advantages and Disadvantages of an Isolette?
They are easy to operate but hard to control due to frequent opening.
The neonate is not readily accessible inside the plastic case.
If the incubator can be left closed they work well and maintain temperature without undue increases in room temperature
What is a Radiant Warmer?
Radiant (i.e. open) warmers make the neonate more accessible.
What are the Advantages an Disadvatages of Radiant Warmers?
They are usually servo controlled to maintain the core temperature of the neonate.
However, the neonate is openly exposed to the environment.
Core temperatures of the maintained easily, but cold stress still may occur because the inability to control the environment
What are the effects of Overstimulation of a newborn?
Sensory overload from the noise, light, and activities of the NICU provide too much stimulation to the eyes, ears, and brain of the neonate.
This can interfere with both the development and organization of the central nervous system
What is behavioral-based care?
Handling only when the behavioral and physiological sign indicate.
Behavioral-based care seeks provide basic care during times of non-stress:
- In theory, this will reduce overstimulation
What can cause Skin Trauma to a newborn, and what are the risks of it?
Because the skin is so thin, removing tape, excessive handling, and other such activities may tear the skin.
This causes the break down the first barrier of their defense system.
This leaves the premature infant much more susceptible to infection.
How do we reduce the risks of Skin Trauma to a newborn?
Use mild soaps applied with cotton ball when cleaning.
Use ETT holders as opposed to taping.
Appropriate placement and relocation of devices like transcutaneous monitors.
Using elastic wraps rather than tape to hold pulse oximeter sensors in place.
Use of transparent IV dressings.
Increasing the infant's environmental humidity.
What are the different electrolytes that concern us and what do they do?
Sodium - water balance
Potassium - acid-base balance and hydrogen diffusion (both are positively charged)
Calcium - integral for heart function and bone integrity
Magnesium - necessary for calcium regulation
Chloride - anion gap and Hamburger phenomenon
Phosphate - essential in energy metabolism
Review Table 7-5 on slide 25.
Do it? Eright good.
What is Jaundice (Hyperbilirubanemia) and facts about it?
Jaundice is the yellow-orange skin color associated with abnormal levels of biliruban.
Most biliruban comes from the breakdown of old red blood cells.
It is common in neonates.
25 to 50% of all term infants.
Higher percentage in premies.
What causes an increase in biliruban (jaundice)?
The higher percentage of red blood cells.
The shorter life span of red blood cells.
The inability of the neonatal liver to conjugate the excess biliruban.
What are compications associated with Jaundice?
Encephalopathy is the most serious complication associated with pathologic jaundice.
This is because the fat from the unconjugated biliruban crosses the blood-brain and attaches itself to the brain cells.
Hyperbilirubanemia, untreated can then lead to permanent brain damage and developmental delay.
How do you treat Jaundice?
Phototherapy (mostly used), where blue light causes the biliruban to decompose into water-soluble particles with are excreted by the kidneys.
Phenobarbital, increases conjugation.
Exchange transfusion, replacing the effected RBC's.
What is Necrotizing Enterocolitis (NEC) characterized by?
NEC is characterized by ischemia and necrosis of the intestines.
Untreated it may lead to abdominal distention, perforation, sepsis, and maybe death
What is Necrotizing Enterocolitis (NEC) associated with?
Necrotizing entercolitis (NEC) is an idiopathic disorder associated with:
- Mucosal wall injury.
- Bacterial invasion of the damaged area.
- Formula feeding.
What is Necrotizing Enterocolitis (NEC)?
Break down and destruction of a portion of the intestines
What are Clinical signs of Necrotizing Enterocolitis (NEC)?
Blood in the stool.
Bile tinged vomiting.
Pneumatosis on x-ray (abnormal presence of air)
General signs of sepsis.
Poorly tolerated feeding.
Increased O2 requirements. (pressure pushes on lungs cause smaller Vt)
What is the Treatment for Necrotizing Enterocolitis (NEC)?
Prevention is the best treatment.
Good hand washing technique.
NG suctioning to remove bile residue.
Frequent abdominal x-rays.
Surgical intervention to repair perforated or necrotic intestines.