TEST 1 Flashcards
1 KG = how many g?
1000
1 g = how may mg and how many mcg?
1000 mg
1,000,000 mcg
1 mg = how many mcg??
1000 mcg
0.1 mg = ____ mcg
100 mcg
0.01 mg = _____ mcg
10 mcg
0.001 mg = ____ mcg
1 mcg
How many mcg/ml of epi is in 1:200,000
1,000,000 divided by 200,000 = 5 mcg/ml
2% Lidocaine = _____mg/ml
20
0.25% Marcaine = ______ mg/ml
2.5 mg/ml
__________ characteristics have a strong influence on a child’s behavior during perioperative response
Parental
Children of parents who are more anxious, children of parents who use avoidance coping mechanisms, and children of separated/divorces parents appear to be at HIGH/LOW risk for developing preoperative anxiety
HIGH
What is PPIA?
Parental Presence during Induction of Anesthesia
Do most parent want to be present during induction? TRUE or FALSE
TRUE
One study found that mothers who were most highly motivated to be present at induction of anesthesia reported LOW/HIGH levels of anxiety and their children were LESS/MORE distressed at induction.
HIGH levels of anxiety
MORE distressed
More than ____% of parents report some degree of anxiety during induction
90%
What is the most upsetting actor for the parent during the induction process?
Seeing the child go limp and then having to leave them
What are some most commonly used pre-op medications that you can use if the child has pre-op anxiety?
Midazolam, Ketamine, Transmucosal fentanyl, Dexmedetomidine
What is the best way to reduce anxiety in your pediatric patient?
Establishing a rapport and telling the child in an appropriate way what is important for the child to know, can make a great difference.
Ask for the child’s favorite stuffed animal or toy.
Play with the child a little and establish good eye contact
What do you want to make sure to mention to the child when building a rapport?
Make sure to mention that NOTHING HURTS and there to keep the child comfortable, and at the end we are waking the child up to meet his or her parents in the “wake up room” PACU.
What is the utmost major importance when it comes to pediatric anesthesia?
The physiologic differences related to general metabolism and to immature function of various organs (heart, lungs, kidneys, liver, blood, muscles, and CNS)
What weight is prematurity usually?
less than 2500 gm (2.5 kg) at birth
A pre-term infant is born before ______ weeks of gestation
37
Term infant is born AFTER ________ wks and BEFORE _______ completed weeks of gestation.
37 weeks and before 42 weeks
Post term infant is born after _______ completed weeks of gestation
42
Neonate is defined as
< 30 days
Infant is defined as
1-12 months
Children is defined as
1-12 years
Adolescent is defined as
13-19 years
What is low birth weight (LBW)?
Less than 2.5 kg
What is Very Low Birth Weight (VLBW)?
Less than 1.5 kg
What is Extremely Low Birth Weight (ELBW)?
Less than 1 kg
What is a “Micro-preemie”?
Less than 750 gm
With a micro-preemie, when is it appropriate to go to surgery?
Emergent surgery
Duration of gestation and the weight of an infant have an important relationship. Deviations from this relation is associated with what (6) things
INADEQUATE MATERNAL NUTRITION (Malnutrion or placental insufficiency)
SIGN. MATERNAL DISEASE (pregnancy-induced HTN, DM, collagen disorders)
MATERNAL TOXINS (tobacco, alcohol, drugs)
FETAL INFECTIONS (toxoplasmosis, rubella, CMV, syphilis)
GENETIC ABNORMALITIES (Trisomy 21, 18, 13)
FETAL CONGENITAL MALFORMATION (Zika virus -> micro/macroencephaly)
What measurement is the most sensitive index of well-being, illness, or poor nutrition over length or head circumference?
WEIGHT
What is commonly used as a measurement of growth?
Weight
This indicates that there may be a serious underlying disorder in a child?
Failure to thrive
How do you calculate IBW for children <8 yrs?
2 x Age + 9
How do you calculate IBW for children > 8 yrs?
3 multiplied by age
At full-term birth, the infant has a _________ neck and a ____________ that often meets the chest at the level of what rib?
Short neck, and a chin at the level of the 2nd rib
Due to short neck and a chin that meets the 2nd level of the ribs, infants are prone to what?
Upper airway obstruction during sleep
In infants with tracheostomy, the orifice is often buried under ______ unless the head is __________ with a roll under the neck.
the chin; extended
In addition, infants are more prone to UPPER airway obstruction under this kind of anesthesia.
GETA
Why are infants more prone to upper airway obstructions under GETA?
Because upper airway muscles (which normally support the airway patency) are DISPROPORTIONALLY SENSITIVE TO THE DEPRESSANT EFFECT OF GETA = pharyngeal airway collapse and obstruction
What is the best thing for you to help the infant with upper airway obstruction?
Place in SNIFF position with JAW THRUST. DO NOT HYPEREXTEND especially with Down Syndrome patient
What are the major differences between neonatal and adult airway? (2)
Tongue: relatively large in proportion to the rest of the oral cavity —-> airway can easily obstruct
Position of larynx: Infants larynx is more cephalad (C2-C3) vs. and Adult (C4-C5)
What type of laryngoscope blade makes visualization of glottic opening easier than a curved bald?
A straight DL (either a Miller or Wis-Hipple)
Infants epiglottis is __________ and ___________-shaped and ________ into the lumen of the airway, making it EASIER/DIFFICULT to displace ANTERIORLY during laryngoscopy.
Narrower
Omega-snapped
Angled
DIFFICULT
The presence of _______________ tonsil and adenoid tissue can cause rapid development of upper airway obstruction after administration of GETA.
hypertrophied
Amount of primary teeth? Begin to erupt when? And shed at what age?
20 primary teeth
Erupt during the first year of life
Shed at age 6-12
What does pre-op physical exam of children include?
Search of loose teeth that could be dislodge during airway management and lost within the respiratory tract.
Examine braces, loose, or damaged pieces.
Amount of permanent teeth? Begin to appear when?
- When primary teeth shed.
When mask ventilating a neonate, what 3 things is associated with airway obstruction?
Unintentional jaw pressure from neck flexion
Submental pressure
Mandibular pressure
What is a common error that most CRNAs make when mask ventilating a pediatric patient?
Holding the mask TOO LOW over the nose and COMPRESS the nasal passages
Also, many infants have some degree of ___________, rendering the supraglottic structured prone to collapse during inspiration.
Laryngomalacia
What is the most effective mask ventilation technique for infants and young children?
For the anesthetist to hold the mask over the mouth and nose with thumb and index finger, while the middle finger is placed on the bony portion of the mandible ——> the chin can be lifted to provide head extension (but be careful) without compressing the soft tissues of the neck. SNIFF POSITION.
To improve airflow during upper airway obstruction in pediatrics, what steps can you do? (3)
Chin lift, jaw thrust, and apply some CPAP (5-15 cm H2O pressure at APL valve)
CPAP can unintentionally do what?
Inflate stomach
Chin lift will extend the head at the ____________________ joint, thus stretching and straightening the airway to DECREASE the severity of soft tissue obstruction
Atlanto-occipital joint
If a correct artificial airway is selected—-> what does it relieve?
Airway obstruction secondary to the tongue without damaging laryngeal structures. Should results in proper alignment with the glottic opening.
If TOO LARGE of an oral airway is inserted, what happens?
The TIP lines up posterior to the angle of the mandible and OBSTRUCTS the glottic opening by pushing the EPIGLOTTIS down.
IF TOO SMALL of an oral airway is inserted, what happens?
Tip lines up well ABOVE the angle of mandible; airway obstruction is thus exacerbated by KINKING the tongue
______ airway may relieve upper airway obstruction as well as provide a useful conduit for delivering O2 and anesthetic gases.
NASAL
To avoid trauma and bleeding of the nasal mucosa, nasal airway should be lubricated and inserted ________________ direction along the floor of the nasal cavity.
Posterior-caudad
When do you AVOID NASAL TRUMPETS in children? (2 things)
Bleeding -> coagulopathy and/or thrombocytopenia
Trauma -> Suspicion of traumatic basilar skull fracture
When compared with ETT, _______ is associated with LESS/MORE laryngeal stimulation and a decreased incidence of airway complications in children with upper respiratory tract infections
LMA;
LESS
Peak inspiratory pressure should not exceed ________ cmH2O to prevent gastric insufflation.
20
When is an LMA not indicated?
Children at risk for pulmonary aspiration of gastric content
What is the LMA size for a pediatric patient with a weight of < 5 kg?
LMA 1
LMA size for 5-10 kg?
LMA 1.5
LMA size for weight 10-20 kg
LMA 2
LMA size for 20-30 kg?
LMA 2.5
LMA size for 30-50 kg?
LMA 3
LMA size for 50-70 kg?
LMA 4
In neonates and small infants, DL is often challenging because of what 2 things?
Smaller and more cephalad location of the larynx; and narrower view through the oropharynx
How do you calculate a child 2-6 years of age for an UNCUFFED ETT?
Age (yrs) + 16
———————
4
CUFFED ETT?
Age (yrs) + 16
——————— - 1/2 size
4
Size of ETT (cuffed or uncuffed) And Depth of ETT for a preterm <1000g?
Uncuffed 2.0
Depth: 6 cm
Size of ETT (cuffed or uncuffed) And Depth of ETT for a preterm <2000g?
Uncuffed 2.5
Depth: 7-9 cm
Size of ETT (cuffed or uncuffed) And Depth of ETT for full term neonate?
Uncuffed 3.0-3.5
Depth: 9.5-10 cm
Size of ETT (cuffed or uncuffed) And Depth of ETT for a 1 year old?
Cuffed 3.0-3.5 (no air applied at times)
Depth: 11 cm
Size of ETT (cuffed or uncuffed) And Depth of ETT for a 2 year old?
Cuffed 4.0-4.5
Depth: 12 cm
Size of ETT (cuffed or uncuffed) And Depth of ETT for a 6 year old?
Cuffed 5.0-5.5
Depth: 14-15 cm
Size of ETT (cuffed or uncuffed) And Depth of ETT for a 10 year old?
Cuffed 6.0-6.5
Depth: 16-17 cm
Size of ETT (cuffed or uncuffed) And Depth of ETT for a 16 year old?
Cuffed 7.0-7.5
Depth: 18-19 cm
Size of ETT (cuffed or uncuffed) And Depth of ETT for a 20 year old?
Cuffed 7.0-8.0
Depth: 20-21 cm
ETT length, where should the black line marking rest?
At the level of the vocal cord, that means that the tip of the ETT is between the carina and VC
After successful intubation, what should you have the MDA do?
While assist-ventilating the child, the MDA slowly advances the ETT and simultaneously listens to breath sounds at the left chest wall
At the moment when the breath sounds are lost, the ETT is where? And what should you do?>
RIGHT MAIN BRONCHUS
Pull back a “centimeter” until bilateral breath sounds occurs
Where is the narrowest part of the infants larynx??
The CRICOID CARTILAGE
Both the adult and infant’s larynx are __________________-shaped, but is more __________ in the infant/toddler
funnel-shaped
Exaggerated
Because of the funnel shaped larynx, when a large diameter ETT is inserted through the glottic opening, the tube passes through the cords, but meets resistance where?
IMMEDIATELY BELOW THE CORDS (subglottic or cricoid ring)
UNCUFFED/CUFFED ETTs are used for premature and full-term neonates/small infants because the cone-shaped trachea will seal off the trachea.
UNCUFFED
CUFFED ETTs may cause what (5) things in premature and full-term neonates/small infants?
Mucosal trauma
Inflammation
Post-intubation croup
Potentially Malacia
And stenosis
Cuffed ETTs are use in children > ______ year with appropriate _________ test.
1 year
“Leak test”
Cuffed ETTs will allow what (3) things?
Adequate ventilation
Less OR pollution
Spares the child from extra DL attempts to change ETT if it is incorrectly sized
Where should your MDA auscultate for leak test?
Cricoid cartilage or sternal notch
What is the purpose of a leak test?
To assess for a leak at 18-20 cm H20 pressure to prevent airway edema/Post intubation stridor
What is occurring when your patient has a large leak around the cuff and you are unable to hold pressure at 20 cm H20? (Floppy green bag)
ETT is possibly too small with a LARGE LEAK
When there is a large Leak, what can your MDA do to your ETT?
The MDA adds first some air into the cuff to seal the leak, hold pressure at 20 cm H20 and then the MDA slightly deflates the air until air escapes (created leak)
What type of leak is occurring when after intubation, you are slowly and steadily closing the APL valve to 20 cm H2O pressure, MDA listens over the patients mouth/sternal notch, squeaky sounds occurs at that particular pressure?
ETT is appropriately sized
If the leak is around 18-20 cm H20 pressure, no air needs to be added
What type of leak is occurring when after intubation, you are slowly and steadily closing the APL valve to 20 cm H20 pressure, there is no leak. Increases to 25-30 cm H20 pressure, and still no leak?
ETT is TOO snug
If the ETT is too snug, what needs to be done?
Replaced by a smaller size
What laryngoscope blade can be used for a pre-term?
Miller 00
Miller 0
What laryngoscope blade can be used for a neonate?
Miller 0
What laryngoscope blade can be used for a neonate- 2 yr?
Miller 1
What laryngoscope blade can be used for a 2-6 yr old?
Wis-Hipple 1.5
MAC 1 or MAC 2 (usually for a McGrath)
What laryngoscope blade can be used for a 6-10 yr old?
Miller 2
MAC 2
What laryngoscope blade can be used for > 10 yr old?
Miller 2
Miller 3
MAC 3
For a nasotracheal intubation, what topical vasoconstrictor medication do you apply bilaterally after induction?
Oxymetazolin 0.05%
NASAL RAE should be placed where prior to use to make it more pliable?
In the OR warmer or placed packaged nasal RAE in a plastic bag in the nozzle of bair hugger
What should you insert before inserting a warmed, lubricated nasal Rae?
Lubricated nasal trumpet to dilate
What do you use to gently guide the nasal RAE into the glottic opening?
DL and Migill forceps
Nasal intubate may cause transient bacteremia, what kind of prophylaxis is indicated?
Endocarditis prophylaxis in susceptible children
What is a reflex closure of the upper airway (glottic musculature spasm)?
Laryngospasm
How is laryngospasm elicited?
Elicited by stimulation for the AFFERENT fibers contained in the INTERNAL BRANCH of SUPERIOR LARYNGEAL NERVE (SLN)
What type of laryngospasm has inspiratory stridor?
Partial laryngospasm
What kind of laryngospasm includes no air movement, tracheal tug, paradoxical movement of the chest/abdomen, desaturation, and bradycardia?
COMPLETE laryngospasm
What can laryngospasm lead to?
Serious morbidity: cardiac arrest, arrhythmia, pulmonary edema, bronchospasm, gastric aspiration
Laryngospasm can also be thought of what other airway obstruction?
Bronchospasm or supraglottic obstruction
What are (4) anesthesia-related factors of laryngospasm?
Insufficient depth of anesthesia during induction/emergence
Insufficient depth during tracheal intubation/extubation
Saliva/blood/mucus or airway manipulation (suction catheter or laryngoscope)
Violate agents (pungent DES/ISO)
What are (7) patient related factors contributing to laryngospasm?
Younger children= greater risk
URI
Active Asthmas
Airway hyperreactivity after respiratory infection (up to 6 weeks)
Smoking exposure
GERD
Hx of elongated uvula of choking during sleep
What are surgery-related factors contributing to laryngospasm?
T&A
Lap Appy
Thyroid surgery (injury to SLN)
Iatrogenic removal of parathyroid gland (hypocalcemia)
Esophageal procedures
What (4) measures can you take to to prevent laryngospasm?
Deepen anesthesia during airway manipulation and IV placement
Awake vs deep extubation
Positive inflation of lungs before extubation
Reduced salivation with small amounts of Glyco
What is the initial treatment for laryngospasm?
Identify and remove the offending stimulus, apply jaw thrust (pressure on laryngospasm notch), insert an oral airway, and apply positive pressure ventilation with 100% oxygen
What medications/actions can you do if laryngospasm persists?
Deepen anesthesia with SEVO
- 5 mg/kg Propofol IV
- 1-1.0 mg/kg SUCC IV
4 mg/kg IM SUCCS
What should you give before administering SUCCS?
Atropine 10-20 mcg/kg IV or 20-40 mcg/kg IM.
NOT LESS THAN 100 mcg
After laryngospasm, what should you assess for?
Gastric distension -> suction stomach with OGT
NPPE (usually occurs in large muscular males)
When do the anatomical structions for gas exchange occur?
Late in gestation
The LIMIT OF VIABILITY IS AROUND _______ WEEK, when the lungs develop a gas-exchanging surface and ________ production begins with what type of pneumocytes
24th week
Surfactant
Type II pneumocytes
From _______ to _______ weeks, Surfactant secretion into the amniotic fluid increases, providing a clinical useful indicator of lung maturity called?
30 to 36 weeks
Lecithin/Sphingomyelin (L/S) ratio
The incidence of respiratory distress syndrome DECLINES rapids during what period of gestation?
35-36 weeks
The infant’s rib cage is _________________ and the thorax is too compliant to resist IN/OUTWARD recoil of the lungs.
Cartilaginous; INWARD
The chest wall is easily deformed, tending to move inward on inspiration. Inspiration occurs almost entirely as a result of what?
Diaphragmatic descent
In the awake state, the chest wall is maintained relatively rigid with sustained inspiratory muscle tension, which maintains FRC. True or False
TRUE
Under GETA, what is abolished and causes the FRC the collapse leading to airway closure and atelectasis?
Muscle tension
How can you prevent airway closure and atelectasis?
Maintain CPAP or PEEP
Periodic breathing commonly occurs in newborns- recurrent pauses in ventilation lasting no more than ____ to _____ seconds with alternating bursts of respiratory activity. What is this pattern of breathing related to?
No more than 5 to 10 seconds.
Related to gestational age and the sleep state REM
What pattern of breathing is life threatening condition (25% of all pre-term infants, mostly premature) that involves desaturation of arterial oxygen, bradycardia and loss of muscle tone?
APNEA OF PREMATURITY
In non-severe cases, apneic episodes may be terminated by _________________ stimulation, but in severe cases, may require what?
Tactile stimulation
Require resuscitative effort with BMV.
What is the risky of postanesthetic respiratory depression INVERSELY relate to?
Gestation age and posconceptual age (PCA) at the time of Anesthesia thesis
What is the sum of gestational age and chronological age?
PCA
What (3) criteria must pre-term infants meets to be discharged from the PACU?
55-60 weeks PCS
NOT ANEMIC
Not experiencing APNEA
Observed for extended period of time, and stable to be LATER discharged
Infants who are younger than 55 weeks’ PCA, anemic wit a hematocrit of _____, and have ongoing apnea should be admitted for what after anesthesia?
<30%
Monitoring
Most URIs are short/long-lived, self-limiting, and may cause increase/decrease airway sensitivity to noxious stimuli?
SHORT-lived
INCREASE
What else can URIs cause? (5)
Arterial oxygen desaturation
Laryngospasm
Bronchospasms
Breath holding
Severe coughing
What kind symptoms present with UNCOMPLICATED URIs?
Afebile with clear secretion and otherwise healthy?
UNCOMPLICATED URI describes what typical patient and should you proceed with anesthesia as planned?
Chronic otitis media schedule for myringotomy (ear tube insertion)
YES, proceed as planned
What are some symptoms of COMPLICATED URIs? (4)
Mucopurulent secretions
Productive cough
Pyrexia > 38 C (100.4 F)
Pulmonary involvement
Elective surgery should be ________ in a child exhibiting complicated URIs?
Postponed
If a bacterial infection is suspected with URIs, what should be prescribed?
Appropriate antibiotics
Apart from URIs, what should you also consider? (6)
Asthma
Cardiac disease
Type and urgency of surgery
Child’s age
H/o prematurity
Frequency of URIs
If you are performing GETA with URI, what can you do as an anesthesia provider? (2)
Minimize secretion
Avoid stimulation of potentially sensitized and inflamed airway
___________ and ___________ are associated with fewer episodes of respiratory events than an ETT.
Mask ventilation and LMA
Depth of anesthesia needs to be __________ to obtund airway reflexes especially during intubation.
ADEQUATE
Removal of LMA/ETT under ______________ anesthesia and suctioning of secretion show LESS respiratory complications during emergence than awake extubation.
DEEP
What is a common CHRONIC disorder of the airways characterized by variable and recurring symptoms, airway obstruction, inflammation, and hyperresponsiveness of the airways?
ASTHMA
What are (5) pathophysiology that occurs with ASTHMA?
Contracted smooth muscle
Blood vessels infiltrated by immune cells
Decreased lumen diameter
Inflammation and swelling
Excess mucus
What are some clinical S/S that occurs with Asthma? (4)
Wheezing
Persistent dry cough
Chest tightness or discomfort
Dyspnea on exertion
Severe respiratory distress may be characterized by? (6)
Chest wall retraction
Use of accessory muscles
Prolonged expiration
Pneumothorax
Progression to respiratory failure
Death
What (2) bronchodilators should be given shortly after induction to attenuate the increase in airway resistance with an asthmatic?
B2 agonists
Corticosteroids
(2) triggers of bronchospasms include?
Airway stimulation during intubation (Mask/LMA preferred over ETT, if possible)
Surgical stimulation (requires adequate depth of anesthesia and analgesia)
If an ETT is mandatory with an asthmatic patient, what should be considered prior to emergence?
Deep extubation
Intra-op bronchospasm is characterized by (6) things?
Polyphonic expiratory wheeze
Prolonged expiration
Increased airway pressure
Slow upslope of ETCO2
Raised ETCO2
Hypoxemia
What other (5) potential causes of wheezing that have the same symptoms as intra-op bronchospasm?
Partial ETT obstruction
Mainstem intubation
Aspiration
Pneumothorax
Pulmonary edema
What potential (5) treatments of intra-op bronchospasm?
Deepen anesthesia/analgesia
Increase FiO2
Increase expiratory (1:2.5)
Repeat B2 agonists
If severe, small doses of Epi 10-20 mcg IV or via ETT
Pulmonary blood flow bypasses the lungs d/t LOW/HIGH PVR and flows via _______________ toward the systemic circulation due to LOW/HIGH SVR.
HIGH PVR
Ductus Arteriosus
LOW SVR
Blood flows toward systemic circulation via _______________ which bypasses the RV and pulmonary circulation.
Foramen Ovale
Blood flows toward systemic circulation via _______________ bypasses the pulmonary circulation due to LOW/HIGH PVR.
Ductus Arteriosus
HIGH PVR
What is between the RA and LA?
Foramen Ovale
What is between the PA and aorta?
Ductus arteriosus
The ductus arteriosus allows the blood to by pass what?
THE LUNGS
Fetal circulation: 1 umbilical vein (from mom) carries DEOXYGENATED/OXYGENATED blood and flows to where?
OXYGENATED
THE LIVER
As the blood flows in the liver, what two places does the blood go?
1) Stays in the liver in the small capillaries to be metabolized
2) through the DUCTUS VENOSUS
As the blood flows through the liver via small capillaries and ductus venosus, where does it eventually lead to?
IVC
The Ductus Venous allows blood to bypass what?
LIVER
The IVC contains what mixture of blood?
Mixed Oxygenated
THE SVC and IVC blood flows to ________; since the ________ pressure is higher than LA pressure; blood preferentially flows to the RV then to _______________ arteries then to the lungs.
RA
RA pressure
Pulmonary arteries
Some blood does flow to the LA from the RA via ______________ which then proceed to the LV and then the aorta and goes to the legs and _________________.
Foramen ovale
Internal iliac arteries
From the internal iliac arteries, the blood flows to the 2 ____________ arteries and back to _________________ due to low pressure?
Umbilical arteries
Placenta
After birth, the neonate takes its first breaths, the lungs INFLATE, and PVR INCREASES/REDUCES while the placenta is disconnected and blood is “not drained back to mom,” thus INCREASING/DECREASING SVR.
PVR REDUCES
INCREASING SVR
After birth, the pressure changes allows for easier blood flow into the lungs which allow the blood to become ______________
Oxygenated
Immediately after birth, the increase pressure in the LA compared with the RA pushes the flap of __________________ shut.
Foramen ovale
After birth, the increased pressure in the aorta allows some “back flow” of blood via ___________ back into the _____________ artery which causes additional oxygenation of the blood (may take hours to days)
Ductus Arteriosus
Pulmonary artery
The ductus arteriosus senses that the placenta is removed causing an INCREASE/DECREASE in prostaglandin levels?
DECREASE in PGs
After birth, the ductus ____________ eventually clots off and may take hours/days.
VENOSUS
Eventually after birth, the pressure changes within the two circulations and the reduced levels of PGs causes the closure of ductus arteriosus (DA) and foramen ovale (FO) IMMEDIATELY after birth. True or False
FALSE. Takes DAYS
In fetal cardiovascular circulation, the fetal lungs are limited by high vascular resistance, therefore the blood bypasses the lungs via _______________ (RA-LA) and ductus ___________ (PA-aorta).
Foramen ovale
Ductus arteriosus
What is the connection between the umbilical vein and IVC -most umbical venous blood from the placentaa bypass the liver to IVC then to RA?
Ductus VENOSUS
Blood supplied to the heart/upper body has LOWER oxygen content (55-60%) vs to abdominal organs, lower limbs, and placenta (65%). True or False
FALSE; HIGHER
65% to heart and upper body
55-60% to abd organs, lower limbs and placenta
After fetal birth, as the neonate transitions to air breathing, what two crucial events in the fetal circulation occurs immediately?
DECREASE PVR and INCREASED SVR
The increase in ______________ afterload causes and IMMEDIATE CLOSURE of the flap valve mechanism of the ____________ and reverses the direction of shunt through the ductus _____________.
Systemic
Foramen Ovale
Ductus arteriosus
During the early neonatal period, reversion to the fetal circulation can occur. If HYPOXIA occurs, _________ increases and reopens ductus arterious which lead to a decline in _____________ oxygenation which results in acidosis which further increases ____________ leading to _______________.
PVR increases
Arterial oxygenation
PVR
Hypoxemia
Until fetal shunt pathways close anatomically, the pattern of circulation is STABLE. True or False.
FALSE
Unstable
If SVR remains HIGHER than PVR, what kind of shunt will you see? And what color is the baby?
LEFT to RIGHT shunt
PINK baby -> transitionally ok
IF PVR becomes more increased due to ____________ and ____________, previous fetal circulation may occur via PATENT foramen ovale (PFO) and or PATENT ductus arterious (PDA), which results in what kind of shunt? And what color is the baby?
RIGHT to LEFT shunt
CYANOTIC
____________ causes pulmonary VASOCONSTRICTION, but systemic VASODILATION, bradycardia, and decreased cardiac output?
Hypoxia
Neonatal hypoxia necessitates? What (2) interventions do you do immediately?
RAPID Intervention to prevent this state to proceeding cardiac arrest.
Give atropine and 100% oxygen
In neonates, what autonomic system usually predominates?
PNS with slowly improving SNS
Stroke Volume is ________ due to less compliant LV and immature SNS, therefore CO is largely ________ dependent.
Fixed
Heart-rate dependent
Bradycardia is invariably accompanied with reduced ___________________.
Cardiac output
The less compliant LV of the neonate is also dependent on an adequate filling pressure, so that means ___________ is followed by a fall in CO.
Hypovolemia
The infants systolic arterial BP is closely related to the circulating blood volume. Blood pressure is an excellent guide to adequacy of blood replacement during anesthesia. TRUE OR FALSE.
TRUE
The hypovolemic infant is unable to maintain an adequate CO; hence accurate EARLY/LATE volume replacement is essential.
EARLY
What is estimated blood volume (EBV) for a preterm neonate?
90-100 ml/kg
What is estimated blood volume (EBV) for a full term neonate?
80-90 ml/kg
What is estimated blood volume (EBV) for an infant (<12 mo)?
70-80 ml/kg
What is estimated blood volume (EBV) for a school aged child (<12 yrs)?
70 ml/kg
What is estimated blood volume (EBV) for a teenager (>12 yrs/adult)?
65-70 ml/Jr
What is estimated blood volume (EBV) for an obese child?
60-65 ml/kg
What is the normal HCT and and HGB for a neonate?
HCT (60%) and Hgb (18-19 g/dL)
At birth: Hgb is __________ which has a higher affinity for oxygen -> picks up more oxygen but does NOT deliver it to the tissues shifting the oxygen-hemoglobin dissociation curve to the LEFT/RIGHT?
HgbF
LEFT
At 2-3 mo: H and H declines steady to a Hgb of _________ g/dL and HgbF is largely replaced by ______.
10-11 g/dl
HgbA
After the age of 3 mo- 1 year: HgbA increases to ?
12-13 g/dl
In preterm babies: earlier and greater fall in Hgb falls to what level?
8-9 g/dl
In preemies, despite the reduction of Hgb, the oxygen delivery to the tissues may NOT be compromised due to the oxygen hemoglobin shifting to the LEFT/RIGHT?
RIGHT (more midline) DUE TO MORE HgbA
Children exhibit different pharmacokinetics from adults because of (4) reasons
Altered protein binding
Larger volume of distribution (Vd)
Smaller proportion of fat and muscle stores
Immature renal and hepatic function
These factors and individual differences in metabolic enzyme may lead to (2)
REDUCE drug metabolism
DELAY metabolism
In some cases what medications may have INCREASE metabolism in neonates?
Extensive first pass metabolism with
PROPANOLOL
MORPHINE
MIDAZOLAM
To achieve the desire clinical response and avoid toxicity in neonates, what should the CRNA do?
Modify the dose and interval between doses
Physiologic jaundice is due to the breakdown of ________ (which release _____ into the blood) and to the IMMATURE/MATURE newborn liver.
RBCs
BILIRUBIN
IMMATURE
Due to the immaturity of the newborn’s liver, they cannot effectively metabolize __________ and prepare it for excretion in the urine.
Bilirubin
Normal physiologic jaundice of the newborn typically appears between _____ and _____ days of life and clears with time.
2nd and 5th
What is a grave from of jaundice characterized by very HIGH levels of UNCONJUGATED bilirubin in the blood, yellow staining, and degenerative lesions in the the cerebral GRAY matter?
Kernicterus (Bilirubin encephalopathy)
What is the treatment for kernicterus?
Phototherapy and exchange transfusion
Some medications may DISPLACE bilirubin from its proteins binding sites and may predispose an infant to ________.
Kernicterus
What drugs may cause kernicterus in the neonate?
Any drugs that competes for ALBUMIN binding sites that increases unconjugated bilirubin include:
Furosemide
Sulfonamides
Diazepam (preservative benzyl alcohol)
What causes kernicterus?
Caused by toxic effects of UNCONJUGATED BILIRUBIN on the CNS
What are the (3) S/S of kernicterus?
Hypertonicity
Opisthotonus
Spasticity
Unconjugated doesn’t normal cross the BBB, but neonates have ____________ BBB.
Immature
GI: Neonates have immature ____________ sphincter, frequent regurgitation or “spitting” of gastric contents even is observed even in healthy infants.
Pharyngo-esophageal
What condition is associated with apnea and bradycardia in preterm infants?
GERD
The placenta is permeable to both insulin and glucagon. TRUE OR FALSE.
FALSE
Impermeable
The islets of Langerhans in the fetal pancrease secrete insulin from the _________ week of fetal life.
11th week
Uncontrolled maternal hyperglycemia results in
Hypertrophy and hyperplasia of the fetal islets of Langerhans
Due to uncontrolled maternal hyperglycemia; this leads to increased levels of ___________ in the fetus, affecting lipid metabolism and giving rise to what size infant?
INSULIN
LARGE, OVERWEIGHT INFANT
Hyperinsulemia of the fetus persists AFTER BIRTH and may lead to rapid development of _______________ which could lead to ____________________.
Serious hypoglycemia (<30 mg/dl)
IRREVERSIBLE CNS damage
When is the cytochrome p450 Enzymes fully functional?
ONE MOS of AGE
________________ when plasma glucose > or equal to 150 mg/dl in neonates. Usually occurs in stressed neonates, particularly LBW infants infused with glucose-containing solution. ____________ has been associated with infection and INCREASED morbidity and mortality.
Hyperglycemia
Hyperglycemia
In order to prevent hyperglycemia during GETA, what kind of soul action should be used?
Dextrose-free solution (LR) to replace small amounts of blood loss, “third space,” and deficit fluid losses
Maintenance fluid requirements may be replaced with glucose-containing solution (D5/0.45 NS) administered with a _____________ infusion pump to ___________ glucose administration and requires a monitoring intraop glucose levels.
CONTINOUS infusion pump
AVOID bolus of glucose
In infants, fluid loss and replacement requirements is related to what (3) things
Insensible fluid losses
UOP
Metabolic rate
Insensible fluid losses are relatively LOW/HIGH during infancy.
HIGH
Insensible fluid losses are due to what (2) factors in infants?
High level of alveolar ventilation
Skin of LBW infants
Because of infants proportionally higher water turnover and the limited ability to concentrate urine and conserve water, ___________ develops rapidly when intake is restricted or losses occur.
Dehydration
Pre-Op NPO Recommendation for clear liquids and chewing gum
2 hrs
NPO requirement for breast milk
4 hrs (easier to break down than infant formula)
NPO requirement for infant formula and light meals (dry crackers/toast, no fat, no meat, no protein)
6 hrs
NPO Requirement for solids
8 hrs
What is the 4-2-1 Rule?
Fluid deficit and Replacement requirement
4 ml/kg for the first 10 kg
2 ml/kg for second 10 kg
1 ml/kg for the remaining kg
How do you calculate the fluid deficit?
Multiply the hourly requirement by the hours of being NPO
When do you give at least 50% of fluid deficit?
BEGINNING of surgery
Pre-term and full-term neonates and small infants have a ________________ compared to ____________ and increase thermal conductance (thin layer of SQ fat)
Large skin surface area COMPARED to body mass ratio
_______________ heat loss is greater in infants due to reduced _____________ content in the infant’s skin.
Evaporative
Keratin
Combination of increased heat loss and diminished efficacy of the thermorequlatory response with reduced ability to generate heat predisposed the infant to ________________.
HYPOTHERMIA.
Protective mechanism such as ___________ of peripheral vessels slows heat loss from our bodies; while _______________ promotes heat loss when exposed to a hotter environment.
Vasoconstriction
Vasodilation
What mechanism is disrupted under anesthesia (specifically since volatile and regional anesthesia causes vasodilation)?
Thermoregulatory mechanism
The initial repaid decrease in core temperature during the first hour of general anesthesia is due to?
Core-to-peripheral redistribution of body heat (normally maintained by thermoregulatory vasoconstriction)
Warms the arms and legs but does so at the expense of the core of the body.
What four primary process encourages heat loss?
Radiation
Convection
Conduction
Evaporation
What is the transfer of energy between 2 objects that are NOT IN DIRECT CONTACT but differe in temperature?
Radiation
What is the most significant mechanism of heat loss by our bodies, especilaly by patients under anesthesia?
Radiation
Radiation of infrared electromagnetic wavelength transfers heat energy from our warm __________ to the less warm __________ environment.
Bodies
OR environment (walls, ceiling, equipment)
Infrared radiation from our bodies is GREATEST in areas of _____________ blood flow.
HIGHEST
What loses the greatest amount of heat flow due to the highest percentage of blood flow?
HEADS
What intervention can reduce radiant heat loss?
Increasing ROOM TEMP, which diminishes the temperature gradient between the patient and the OR environment
Apart from increase room temp, what can also further dramatically reduce the loss of radiant energy?
A thin (plastic) cover
What is the process of creating air currents by heat? This is when our bodies transfer kinetic energy to air molecules on the surface of our skin. The heated air molecules move about with greater kinetic energy, rise and replaced by colder (less kinetic) air molecules.
Convection
When thinking of convection, it helps to think in terms of _______________.
Currents (wind chill factor)
Approximately what percent of heat loss from body normally occurs by radiation and convection combined?
70%
40% radiation
30% convection
What type of heat loss include moisture leaving from the patient’s skin as well the respiratory tract (exhaled water vapor)? This includes patients who are sweating as well as patients who have areas of their bodies surgically prepped with liquids (isopropyl alcohol, povidone-iodine, and chg).
Evaporation
Evaporation is usually NOT a high heat loss in adult patients, but is significant in pediatric patient when using what kind of flow rates?
HIGH GAS FLOW RATES
How can you prevent evaporation loss?
Low FHG (if appropriate)
Use of HME (in-line humidifying apparatus)
Through which route does a burn patient lose the highest percentage of body heat?
EVAPORATION
What type of heat loss is the transfer of heat by physically touching a less warm object? This is when two objects are in DIRECT CONTACT, heat exchange occurs from high to low concentration called entrophy.
Conduction
A patient on the cold OR table will conduct his heat to the less warm OR table wherever physical contact is present. True or False.
TRUE
Conduction is usually not a significant process in pediatric patients. True or False
FALSE
Pediatric patients have a large ____________ to mass, therefore conduction is significant.
Body surface area
What intervention can you apply to prevent conduction loss?
Use of warming blankets on OR table; this reverses the heat transfer.
Rate the four routes of heat loss from HIGHEST to LOWEST percentage
Radiation
Convection
Evaporation
Conduction
What are all (5) effective heat loss important to decrease higher morbidity experienced by hypothermic patients?
Using forced warm air devices
LOWER gas flow rates
Humidification systems
Warming the OR
Covering and insulating the patients
In adults and older children, heat production is principally a function of __________, accompanied by increased oxygen demand.
Shivering
In order to regulate temperature, infants PRIMARILY rely on
Non-shivering thermogenesis to generate heat
Where can you find brown adipose tissue?
Scapulae
Axillae
Mediastinum
Around kidney/adrenal glands
__________ fat is highly vascularized and richly innervated with sympathetic nerve fibers. The ________ color is caused by an abundance of ___________ which are able to uncouple oxidative phosphorylation, resulting in heat production.
Brown fat
Brown color
Mitochondria
Nonshivering thermogenesis is possible within hours after birth and may persist up to what age?
2 years
When is nonshivering thermogenesis reduced?
In infants anesthesized with inhalational agents, propofol, fentanyl
Sick infants are unable to compensate with __________ oxygen demand and glucose use/acidosis when exposed to low ambient temperature.
INCREASED
During anesthesia, what happened to normal thermoregulatory response of the infant? (3)
Normal thermoregulatory response of the infant to cold stress is loss
Skin vasoconstriction is inhibited
Redistribution of body heat away from central core
Cold stress and hypothermia affects?? (5)
Recovery from anesthetic and relaxant drugs
Impair coagulation
Depress ventilation
Dysrhythmias
Increase post op oxygen consumption
In order to maintain temperature homeostasis, what should you do?
PREVENT COLD STRESS and Avoid HYPOTHERMIA
What (5) interventions can you do to conserve body heat in infants?
Adjust OR temp to 24 C (75 F)
Use bair hugger (prevent direct heat blowing onto infants skin)
Use IV fluid warmer. Excess skin prep solution should be wiped off, avoid pooling of irrigation
Use esophageal(should be in the lower third of esophagus) or rectal temp probe
Increase OR temps before the drapes come off
What is the significance of brown fat?
Infants respond to COLD STRESS by increasing norepinephrine production which enhances metabolism of brown fat and increases body heat
What is far more dangerous than hypothermia? The body’s response is limited to active vasodilation and sweating.
HYPERTHERMIA
Hyperthermia sometimes develops during surgery if heat-conserving measure are used. What can you do to prevent hyperthermia?
Turn down the bair hugger or lower temp or ambient air
What are the (3) causes of hyperthermia?
Heat conserving measures (bair hugger)
Pyrexial reactions (manipulation of an infected organ or blood transfusion reaction)
And RARELY, malignant hyperpryrexia syndrome
We used to ignore the need for ______ during painful procedure and surgical operation in infants and children.
Analgesia
What are some S/S that can be seen in a pre-term infant in pain?
Crying
Grimacing
Restlessness
Tachycardia
HTN
IICP
Neuroendocrine response
There is NO evidence to suggest that infants who are subjects to painful procedure (eg circumsion) without anesthesia may experience increased sensitivity to pain as they grow older. TRUE or FALSE
FALSE, + evidence
The posterior fontanelle closes at what age?
4 months
The anterior fontanelle closes at age?
9-18 mos
The anterior fontanelle should be palpate to assess whether it is _____________ (dehydration) or ____________ _____________ (which suggest increase ICP such as in hydrocephalus, infection, hemorrhage of increased PaCO2)
Sunken
Or bulging abnormally
If the anterior fontanelle is bulging, what else should be palpated to ensure there is is no abnormal separation due to increased intracranial pressure?
The sutures (frontal and sagittal sutures)
Autoregulation of CBF is impaired in sick newborns- therefore blood flow is _____________ dependent.
Pressure
In a neonate, cerebral vessels are very fragile and ______________ of these vessels lead to intracranial hemorrhage (especially in the first days of life)
RUPTURE
What are (7) predisposing factors that can lead to intracranial hemorrhage in a newborn?
Hypoxia
Hypercapnia
Hypernatremia
Fluctuations in arterial/venous pressure or CBF
Low Hct
Overtransfusion and rapid administration of hypertonic fluids (dextrose/bicarb)
_________________ occurs in approximate 50% of extremely low birth weight (ELBW < 1 kg) infants with the incidence being INVERSELY proportional to birth weight and gestational age. The pathogenesis of this disease is not completely understood, but VARIATIONS IN ARTERIAL OXYGENATION (HYPOXIA OR HYPEROXIA) and exposure to bright light plays a big role.
Retinopathy of Prematurity (ROP)
One theory of ROP states that the combination of hyperoxic vasoconstriction of retinal vessels, induction of vascular growth factor and free oxygen radicals damage _________________________.
The spindle cells in the retina -> retrolental fibroblasts
To help prevent ROP, during anesthesia for premature and term neonates, we use the lowest __________________ that provides saturation between ______ and ______ and to strive to avoid _______________________.
Lowest inspired oxygen concentration
O2 says between 90-95%
To avoid significant fluctuations in oxygen saturations
The risk of ROP becomes neglible after what week? And why?
44 weeks because retinal vasculogenesis is complete between 42-44 weeks postconception.
Neonatal retrolental fibroblasts is a result of oxygen toxicity about what % of inspired oxygen?
Above 40%
Your ophthalmology surgeon might complain that the patient’s anesthesia depth is inadequate if the eyeballs are rotating UPWARD. (Especially when the eye is irritated or exposed to noxious stimuli) What is this called?
Bell’s phenomenon
For strabismus correction to maintain the eyeball midline, what should you do?
Increase the patient’s anesthesia depth
During ophthalmology surgery, if the eyeballs rotate DOWNWARD, what do you need to do?
Decrease the anesthesia depth
What five ways is the premature infant different from full term neonate? (5)
Suck
Swallow
Sustain ventilation
Maintain body temp
Eat
Which two muscle relaxants can be given IM to break laryngospasm (MM)/
Succs and Roc
3 mg/kg Succs= 85% relaxation
4 mg of Succs in deltoid = 20 minute duration
A 2 year old develops laryngospasm postoperatively and becomes bradycardic. Should atropine be give prior, concurrently, or after succs? Explain your answer (MM)
Atropine 0.02 mg/kg followed by succs
Bc succs mimics the effect of acetylcholine at cardiac muscarinic receptors, which can precipitate more severe bradycardia, junctional rhythms, or sinus arrest
Surgery in neonates poses a major concern-development of apnea in the post op period. Which neonate are the HIGHEST risk for post op apnea (4) (MM)
Premature
Multiple congenital anomalies
History of apnea and bradycardia
Chronic lung disease
At what conceptual age is surfactant developed? (MM)
Surfactant appears initially between 23-24 weeks gestational ages and increases in concentration in the last 10 weeks of gestational life.
The infant patient is high risk for postoperative apnea, which agent may be given prophylactically to decrease the risk of apnea? (MM)
Can give caffeine prophylactically to ensure adequate serum levels exist prior to surgery and during postop period. Caffeine is a RESPIRATORY AND CNS stimulant and is generally preferred to theophylline bc has a wider therapeutic margin
Loading dose: 10 mg/kg (usually obtaine from 20 mg of caffeine citrate)
Clinical effects may last several days, but do NOT administer caffeine and then discharge the patient assuming it will prevent apnea
How many breaths per minute should be produced by the ventilator for the neonate? Adult? (MM)
Neonate: 30-50 breaths/min
Adult: 12-16 breaths/min
