Pediatric Anesthesia Flashcards
When does organogenesis of the fetus take place?
In the first eight weeks
When does fetal organ function develop?
During the second trimester
When does the fetus begin to gain weight?
During the third trimester
When do genetic malformations occur in the developing fetus?
They can occur at any time during the pregnancy
What type of circulation occurs in the fetus?
Serial circulation
Where is oxygenated blood directed in fetal circulation?
Placenta –> umbilical vein –> ductus venosus into IVC –> RA–> foramen ovale –> LA –> LV –> Ascending aorta to brain
Where is deoxygenated blood directed in fetal circulation?
SVC –> RA –> RV –> pulmonary artery –> PDA –> Aorta where blood is directed to the lower body
What physiological changes occur when the infant breaths for the first time?
Decreased pulmonary vascular resistance
PVR decreases increased blood flow to the lungs
LA pressures increase which closes the foramen ovale
What physiological processes occur when the placenta is clamped from the newborn?
Increased SVR and decreased IVC blood flow and RA pressure
What causes the ductus arteriosus to close?
Increased SVR and aortic pressure above pulmonary pressure reverse blood flow through DA
Decreased prostaglandins from additional O2 concentration
When should permanent closure of the PDA occur?
Usually completed within 5-7 days but may persist until three weeks
What is the difference between a functional and anatomical closure of the PDA?
Functional = immediate Anatomical = 2-3 weeks
What features cause the change of fetal circulation to adult like circulation?
The placenta is removed, lungs expand, pulmonary VR decreases, SVR increases, blood oxygenated through the lungs, portal BP falls, DA, PDA and DV close
What term is used to describe the critical period when an infant can readily revert from adult circulation to fetal type circulation?
Transitional circulation
What can cause transitional circulation to occur?
Hypoxia (increases pulmonary VR and can cause PDA to reopen) Acidosis Hypothermia CHD Infection
What can occur if the PFO is reopened?
R –> L shunt leading to hypoxemia
What can occur if the PDA is reopened?
L –> R shunt leading to pulmonary overload
How much of the infants myocardium is non contractile?
60% compared to adults is 30%
What is the significance of the large amount of non contractile myocardium of an infant?
Stroke volume is fixed, non compliant and poorly developed left ventricle
What factor determines CO of an infant?
Heart rate since stroke volume is fixed
What is the hallmark sign of hypovolemia in an infant?
HoTN without tachycardia
What factors can cause bradycardia in an infant?
Hypoxia
Vagal stimulation (DL)
Volatiles
What should be considered the first cause of bradycardia in an infant?
Hypoxia, however consider anticholinergics if bradycardia is severe and symptomatic
What is a good rule of thumb in calculating a SBP and DBP in a pediatric patient?
SBP = (age x 3) + 90 DBP = (age x 1.5) +50
Why isn’t extrauterine life not possible until after 24-25 weeks gestation?
Lung maturation occurs much later in fetal development
When does surfactant production begin to occur in the fetus and what type of cells produce it?
22 weeks surfactant production begins from the type II pneumocytes
What is the function of surfactant?
Alveolar lining layer that stabilizes the alveoli, preventing their collapse on expiration
Why might infants delivers via c-section have more residual fluid in the lungs compared to vaginal deliveries?
During vaginal delivery approximately 90mL of fluid is forced from the lungs via the vaginal squeeze
Why do infants tire quickly from respiration thus leading t apnea?
They have a low number of type I muscle fibers which are marathon muscles
When are type I muscle fibers developed in the pediatric patient?
At least 6-8 months of age
What cause diaphragmatic breathing in children?
Their chest wall is more horizontal and pliable, minimal vertical movement causes decreased room for lung expansion
What is the oxygen consumption requirement of a child compared to an adult?
O2 consumption is 2-3x higher in a child compared to an adult
Why do children have increased resistance to air flow?
Smaller diameter of the airways
How is FRC different in pediatric patients?
It is decreased and the closing capacity is increased
How does CO2 production vary between pediatric and adults?
Peds 6mL/kh
Adults 3mL/kg
Its doubled in the pediatric patient
Why are pediatric patients more sensitive to drugs that affect the CNS?
The BBB is immature, rendering the developing brain more vulnerable to drugs or toxins
How is autoregulation impacted in a sick neonate?
It is impaired and therefore dependent on pressure for blood flow
Why are pre term neonates at risk for intraventricular hemorrhage?
They have very fragile cerebral vessels
What factors predispose a pre term neonate to IVH?
Hypoxia, hypercarbia, hypernatremia, fluctuations in pressure, low HCT, over transfusion and rapid administration of hypertonic fluids
What causes retinopathy of prematurity?
Hyperoxgenation, maintain sats 90-95% to avoid giving too much O2
What is retinopathy of prematurity?
The arrest of normal retinal vascular development in exchange for retinal vessel proliferation
What are the consequences of retinopathy of prematurity?
Fibrous tissue formation and retinal detachment
What does the terms periodic breathing indicate in an infants?
Rapid ventilation with periods of 5-10 second apnea occurs in preterm infants and some full term infants
When should periodic breathing cease in an infant?
44-46 weeks post conceptual age
What is considered apnea in an infant?
No breathing for greater than 20-30 seconds
What symptoms can accompany apnea in an infant?
Bradycardia less than 80bpm
Desaturations
What pediatric age group is most likely to experience post op apnea?
Preterm infants up to 60 weeks post conceptual age
What pharmacologic intervention could help to prevent apnea in the infant?
Caffeine 10mg/kg (preservative free)
How long does an infant have fetal hemoglobin?
In utero and persists until roughly six months of age
What is the difference between adult hemoglobin and fetal hemoglobin?
Fetal hemoglobin can binds to oxygen with a greater affinity which allows the mothers oxygen to be delivered across the placenta
How is the oxyhemoglobin dissociation curve affected by fetal hemoglobin?
Causes a leftward shift
What is the P50 of fetal hemoglobin?
19 compared to adult Hgb 26
What causes physiologic anemia in the infant?
Fetal Hgb synthesis deactivated and adult Hgb synthesis activated, Hgb levels begin to decline around week three
What is usually the goal Hct in an infant?
30%
Why pediatric patients have a increased risk for heat loss?
Larger surface area
Thin skin
Lower fat content
What are the four routes of heat loss?
Radiation (39%)
Evaporation (24%)
Convection (34%)
Conduction (4%)
How does hypothermia affect the pediatric patient?
Delayed awakening from anesthesia Cardiac instability Respiratory depression Increased PVR Altered drug response
Why is shivering severely limited in premature infants?
Small amount of brown fat stores
When does normal kidney function occur in the pediatric patient?
Not present until greater than six months of age
How did the kidneys function in utero?
Passive, reduced GFR and RBF
When are infants able to concentrate urine?
At about one month old
When is phase II metabolism (making drugs more water soluble) functional?
At about 1 year old
Why do pediatric patients have a greater level of unbound drug?
Limited ability to handle large protein loads and have low albumin
Why are neonates predisposed to hypoglycemia?
Neonates have very low glycogen stores
At what level are pediatric patients considered to be hypoglycemic?
At less than 40mg/dL
What can be done to avoid hypoglycemia in a neonate required to be NPO?
Maintained on IV dextrose infusions when NPO
How is calcium homeostasis maintained after birth?
Reliance on calcium reserves however, parathyroid function is not fully established and vitamin D stores may be inadequate
How should hypocalcemia be treated in the neonate?
SLOW infusion of calcium chloride or calcium gluconate
Why do pediatric patients have a larger volume of distribution for water soluble drugs?
They have greater total body water content
Less muscle mass and fat
How can weight of a child generally be estimated?
(Age x 2) + 9 OR
if they are less than 1 (mos/2) + 4
What are common water soluble dugs we use in anesthesia that would require a larger dose in the pediatric population?
Succinylcholine
Bupivicaine
most Antibiotics
At what age does the BBB begin to mature?
By the age of 2
What type of drugs do pediatrics have a decreased volume of distribution to?
Fat soluble drugs due to decreased fat and muscle mass (fentanyl & thiopental)
How is does onset of volatile anesthetics change in the pediatric population?
Inhaled anesthetic concentration in the alveoli increases more rapidly with decreasing age (infants > children > adults)
What factors contribute to the rapid rise of volatile anesthetics in pediatrics?
Increased RR (high minute ventilation)
Decreased FRC
Increased cardiac index, high blood flow to vessel rich organs
Why are blood pressures in pediatric patents so sensitive to volatile anesthetics?
Lack compensatory mechanisms
Immature myocardium
Reduced calcium stores
In what way does MAC change with age?
Infants have higher MACs than older children and adults
What is the blood gas partition coefficient and MAC of N2O?
B/G: 0.47
MAC: 104%
What types of cases is N2O contraindicated?
Pneumothorax, NEC, and bowel obstruction
What gas law explains the second gas effect?
Daltons Law of partial pressure
What is the volatile agent of choice in pediatrics?
Sevoflurane because it is less pungent and less irritating to the airways
What is the blood gas partition coefficient and MAC of Sevo?
B/G: 0.68
MAC: 2%
What can occur if low flows are used with Sevo?
CO2 absorbers containing barium hydroxide or soda lime can increase the production of Compound A
What is the B/G coefficient of Isoflurane and its MAC?
B/G: 1.4
MAC: 1%
What is the B/G coefficient and MAC of Desflurane?
B/G: 0.42
MAC: 6%
Why is it controversial to use Desflurane with a LMA?
There is a high probability of laryngospasm
What is the IV induction dose of Propofol in the pediatric patient?
2.5-3mg/kg IV
At what dose of Propofol infusion does nerve monitoring become an issue?
Greater than 120-130mcg/kg/min
What are the doses of Ketamine used in the pediatric population?
1-2mg/kg IV Induction
2-5mg/kg IM sedation
What medication should always be given with ketamine in pediatric patients?
Glycopyrrolate 0.01mg/kg IV to prevent excessive secretions
Why isn’t Etomidate widely used in peds?
Pain on injection Anaphylactoid reactions Suppression of adrenal function Myoclonus Laryngospasm
What dose of Morphine is typically used in peds?
0.025-0.05mg/kg
Why do some providers prefer not to use Morphine in peds?
Histamine Release, Hepatic conjugation is reduced and Renal clearance is decreased
What is the dose of Hydromorphone in peds?
5-10mcg/kg IV
What is the dose of Fentanyl given to peds?
0.5-1mcg/kg
What is the pediatric dose of Naloxone?
0.5-1mcg/kg
What is the dose of Midazolam given to a pediatric patient for premedication?
0.5mg/kg PO
What is the IV dosing of Midazolam for pediatric patients/
0.05mg/kg IV
What is the pediatric dose of Flumazenil?
2-20mcg/kg IV
What is the dose of Clonidine given to pediatric patients for premedication?
4mcg/kg PO
How much Clonidine can be added to a block in a pediatric patient for prolonged effects?
1-2mcg/kg
Why is Dexmedetomidine preferred for sedation in pediatric patients compared to Clonidine?
It is eight times more specific for the Alpha 2 adrenergic Receptor than Clonidine
Why must Dexmedetomidine be administered slowly when given IV?
It can cause bradycardia
What is the dose of Dexmedetomidine for pediatric patents?
- 25-1mcg/kg IV OR
0. 2-2mcg/kg/min for continuous drip
How is the onset of muscle relaxants different in the pediatric population?
All relaxants have a shorter onset because of shorter circulation times
Why is it difficult to assess the effects of relaxants with a PNS in peds?
Electrodes may over lap or be too close
What is the dose of Succinylcholine in the pediatric population?
2mg/kg IV
4mg/kg IM
What is the IV dose of succinylcholine in a pediatric patient who has laryngospasmed?
0.25-0.5mg/kg
Why might pediatric patients have increased sensitivity to non-depolarizing NMBA?
Immaturity of the neuromuscular junction and increased exntrajunctional receptors
Why cant cisatracurium be given IM like all the other muscle relaxants?
Undergoes Hoffman Elimination
What is the dose of Toradol in pediatric patients?
0.5mg/kg IV, should not be given to patients less than two years old
What type of procedures is Toradol contraindicated in?
ENT and some orthopedic procedures
What should be given to pediatric patients if hypoglycemia occurs?
10% Dextrose 1-2mL/kg
Why should D50 never be given to pediatric patients?
Vessel necrosis and High osmolarity can cause cerebral edema
How should D50 be diluted to get a concentration of D10?
D50 = 50g/100mL = 0.5g/mL
Take 1mL of D50 and dilute it into 4mL of sterile water
Final concentration 0.1g/mL –> D10
What is the code dose of Epinephrine for pediatrics?
10mcg/kg
How do we calculate maintenance IVF rate in the pediatric patient?
4mL/kg for the first 10kg
2mL/kg for the next 10kg
60mL + 1mL/kg after 20kg
How should NPO deficit be replaced?
NPO hours times maintenance
50% given in first hour
25% given second hour
25% given third hour
How much fluid should be given to a pediatric patient prior to induction?
10-20mL/kg bolus
What is a risk factor for pediatrics receiving 5% dextrose in 0.45% NS for maintenance?
Risk for hypoglycemia
Why is it so important not to overload the pediatric patient with fluid?
The kidneys are unable to excrete large amounts of excess water or electrolytes
The volume in the extracellular fluid space is larger than adults
What should always be used when transfusing a pediatric patient with RBCs?
Filter and Warmer
How do you calculate the max allowable blood loss?
[EBV x (starting Hct - target Hct)] /starting Hct
How do you calculate the volume of PRCs transfused to a pediatric patient?
[(desired Hct-present Hct) x EBV] / Hct of PRC which is about 60%
When is fresh frozen plasma given to a pediatric patient?
To replenish clotting factors lost during massive transfusion often when EBL exceeds 1-1.5 the EBV
What should be used when administrating FFP to a pediatric patient?
Filter and Warmer
At what point will we transfuse a pediatric patient with platelets when ITP or chemo has been used?
Tolerate platelet counts as low as 15,000mm3
At what point will we transfuse a pediatric patient whose platelet count is decreased because of dilution?
Generally require transfusion when the count is less than 50,000mm3
What devices should be used when transfusing platelets to a pediatric patient?
Filter only warmer will cause the platelets to stick together
What electrolyte is often depleted after major transfusions?
Calcium binds to citrate preservative
What are often indications that the patient may be hypocalcemic after transfusion?
Cardiac depression with hypotension
What blood products contain calcium citrate?
PRBC and FFP
What can be done to blood products to prevent graft versus host disease in cancer and immunocompromised patients?
Irradiated blood products
What infection can be avoided by filtering blood products?
CMV infection
What can be done to blood products to prevent life threatening allergic reactions to blood products?
Washing products
What is the dose of calcium that should be given if hyperkalemia results from massive blood product transfusion?
Calcium Gluconate 30-100mg/kg (max 3g)
Calcium Chloride 10-20mg/kg (max 1g)
What is the dose of bicarb that should be given if hyperkalemia results from massive blood product transfusion?
1mEq/kg IV
What is the dose of glucose and insulin that should be given if hyperkalemia results from massive blood product transfusion?
Dextrose 1-2g/kg (use 10 or 25%)
Insulin 0.1 units/kg
What is the dose of Kayexalate that should be given if hyperkalemia results from massive blood product transfusion?
1-2g/kg via NG tube or PR
What can be done to help with hyperkalemia if the patient is mechanically ventilated?
Hyperventilate the patient
What inhaled medication can help in lowering K in a hyperkalemic crisis?
Albuterol (beta agonist)
What is the most common indication for a T&A in North America?
OSA
What would make you admit a patient who had a T&A?
Less than 3 y/o Abnormal bleeding tendencies Significant OSA Airway abnormalities Systemic disease Live an excessive distance
What are strong recommendation post T&A?
Single dose of decahedron 0.5mg/kg
No antibiotics
Pain Management
What pain medications should be avoided with T&A procedure?
Avoid codeine (active metabolite morphine) and ketorolac (increased hemorrhage rate)
Why must patients be at an adequate level of anesthesia before incision?
Mouth gag is extremely stimulating
Why might breath sound be lost after placement of a out gag?
Can dislodge ETT
What may be a major cause of nausea in patients after a T&A?
Swallowing lots of blood, ensure to suction GI contents prior to extubation
What is the pediatric position after extubation?
On one side with the head slightly down, allows contents to drain away from the vocal cords
What is considered a primary hemorrhage post T&A?
Occurs within 24hrs of surgery
What is considered a secondary hemorrhage post T&A?
Occurs after 24hrs (5-10days)
Why is a myringotomy and tympanstomy usually preformed?
To alleviate pressure from the middle ear
What kind of anesthetic can be preformed with BMT?
Mask anesthetic, d/c Sevo when working on second ear
What is the most common CNS defect that occurs during the first month of gestation?
Mylomeningocele (spine bifida)
What is the difference between meningocele and myelomeningocele?
Meningocele only contains meninges
Myelomeningocele contains meninges and neural elements
Where is the most common place for a mylomeningocele to occur?
In the lumbarscral region
Why is a mylomeningocele considered an emergency case?
Risk of infection or worsening cord function
Why would a VA shunt revision be done compared to a VP shunt?
If there was infection or pathology in the abdomen
What is a major benefit to using a VP shunt versus a VA shunt?
It allows room for growth
What should be avoided in placements of CSF shunts if the ICP is elevated?
Avoid premeds if ICP is increased
What anesthetic intervention can cause difficulty when cannulating the ventricle for a VP shunt?
Hyperventilation
What is important to do when the surgeon is tunneling for a VP shunt?
Maintain paralysis, extremely stimulating
What are the most common elbow fractures in children?
Supracondylar fractures of the humerus
What are complications associated with a humerus fracture in kids?
Compartment syndrome (NO regional) Nerve palsies Late deformities
When is surgical intervention required in patients with scoliosis?
Patients whose curves are greater than 45 degrees while still growing or are continuing to progress greater than 45 degrees when growth has stopped
What interventions can be done to decrease the amount of blood loss in a spinal instrumentation?
HoTN technique on dissection (maintain 20% baseline)
Use of TXA, cell saver and autologous blood
In patients with scoliosis, what can impair respiratory function?
Cobb Angle which is the degree of lateral curvature
What type of restrictive respiratory pattern is usually seen with scoliosis?
Decreased TLC and VC
What drug affects the amplitude of both SSEPs and MEPs?
Ketamine
What dose of dexmedetomidine will not interfere with MEPs and SSEPs?
Less than 0.3mcg/kg/hr
After an X-ray is completed with spinal surgery, what should be done prior to extubation?
Ensure the surgeon has seen the X-ray prior to extubation in the case that he may have to reenter
What is the suggested intraabdominal pressure for a pediatric patient?
10-12mmhg
What surgical intervention can be done when medical management of reflux has failed?
Abdominal Nissen
What is a nissen procedure?
Mobilizing the muscles around the esophagus at the level os the LES
What are indications for a circumcision?
Phimosis, recurrent balanitis and parental preference
What are the landmarks for caudal anesthesia?
Sacral Hiatus and two PSIS
How are caudal blocks dosed for dental and anal surgery?
0.5-0.75mL/kg (sacral)
How are caudal blocks dosed for lower abdominal and extremity procedures?
1mL/kg (sacral up to low thorax)
How are caudal blocks dosed for abdominal procedures?
1-1.25mL/kg (sacral up to mid thorax)
How much epinephrine should be added to a caudal block?
0.5mcg/kg
How much clonidine should be added to a caudal block in order to increase its duration?
1-2mcg/kg
What problems are often associated with cleft lip and cleft palate in the pediatric patient?
Difficulty feeding
Malnutrition
Speech development
Congenital heart defects
How does an IO needle function?
The needle is injected through the bone’s hard cortex and into the soft marrow interior which allows immediate access to the vascular system
Where is the most common site to place an IO in a pediatric patient?
Antero-medial aspect of the upper tibia
What is the preferred induction agent in peds with hypovolemia?
Ketamine 1-2mg/kg IV
In an airway emergency, how might the provider secure the airway?
Awake fiberoptic
Awake Tracheostomy
Blind nasal
What is a Laryngospasm?
Involuntary spasm of the laryngeal musculature caused by stimulation of the superior laryngeal nerve
What are preoperative factors that can contribute to the cause of a laryngospasm?
Exposure to second hand smoke Concurrent or recent URI Reactive airway disease GERD Irritants such as secretions
What are intraoperative factors that can contribute to the cause of a laryngospasm?
Excitement phase of inhalation induction
Tracheal intubation/extubation during light anesthesia
Upper airway surgical procedures (T&A)
What time is laryngospasm most common in the child?
During induction, but can occur at any time
What are clinical signs of a laryngospasm?
High pitch inspiratory stridor
Progress to silence
Suprasternal and supraclavicular retractions
Paradoxical chest movement
Desaturation –> bradycardia –> asystole
How should a laryngospasm be treated?
Remove any precipitating factors
Positive pressure with 100% FiO2
Jaw thrust
Deepen the anesthetic
What are the IV and IM doses of succinylcholine in the pediatric patient experiencing a laryngospasm?
0.5-1mg/kg IV
4mg/kg IM
What dose of Propofol should be given if a pediatric patient is experiencing a laryngospasm?
Propofol 1-2mg/kg
What dose of Lidocaine should be given if a pediatric patient is experiencing a laryngospasm?
1-1.5mg/kg
What dose of Atropine should be given with Succinylcholine if a pediatric patient is experiencing a laryngospasm?
0.02mg/kg
What is postintubation croup?
Subglottic edema
When would the provider start to see symptoms postintubation croup?
Usually symptomatic within the first hour after extubation with maximum edema usually occurring at 4hrs after extubation and resolving by 24hrs
What are clinical manifestations of postintubation croup?
Braking Stridor Retractions Hypoxemia Mental status changes
What are the main causes of postintubation croup?
Traumatic or repeated intubations Tight fitting ETT Prolonged intubations Surgery of head/neck Coughing or bucking on the tube
How is post intubation croup treated?
Humidified oxygen by mask, can add recemic epinephrine
Consider decadron
May keep over night for observation
What dose of decahedron should be given for postintubation croup?
0.5mg/kg
What dose of recemic epi should be given to a patient with post intubation croup?
0.25-0.5mL of 2.25% solution in 3mL of NS administer via nebulization facemask
What is acute epiglottitis?
An inflammation of the supraglottic structures that can occur at any age
What pathogen most commonly causes acute epiglottitis?
Haemophilus influenza type B
What are the most common clinical manifestations of patients with acute epiglottitis?
Rapid onset over 24hrs
Sitting forward, leaning forward, drooling and tri pod position
Sore throat, fever, muffled voice and dysphagia
What is seen on an X-ray in a patient with acute epiglottitis?
Thumb sign, epiglottis swollen and looks like a thumb
Why is the population shifting from peds to adult patients in acute epiglottitis?
Due to the Hib vaccine
What are two common diagnoses that can be falsely diagnosed when acute epiglottitis is present?
Croup and Foreign body in the airway
Why shouldn’t an airway assessment be performed on a patient with suspected acute epiglottitis?
Potential for irrevocable loss of the airway
How should an airway be established in patients with suspected acute epiglottitis?
Strict monitoring conditions in the operating room, while maintaining spontaneous ventilation
Readiness of a team capable of performing an immediate tracheostomy
What are ideal intubation conditions in patients with acute epiglottitis?
Inhalation induction or IV induction sitting with spontaneous respirations, avoid muscle relaxants
Fiberoptic nasal or rigid bronchoscopy using ETT with reduced diameter
What symptoms are associated with aspiration of a foreign body?
Respiratory distress Cough Stridor Drooling Aphonia
What symptoms are associated with unwitnessed foreign body in the airway?
Fever
Chest pain
New onset of asthma
What are items commonly aspirated into the right side of the bronchus compared to the left side?
The angle is less on the right (20-30 degree) compared to the left (40-50 degree)
Why do you want to keep the child spontaneously breathing if there is a foreign body aspiration?
Could push the object further into the lungs
What should be done if complete airway obstruction occurs?
Requires CPR and ECMO
What type of anesthesia should be done for a foreign body aspiration?
TIVA with propofol, preceded, ketamine or remifentanyl
What additional drugs can be given for a foreign body aspiration?
Glycopyrrolate reduction of vagal tone and antisialagogue
Corticosteroids
Recempic epi
What are the clinical manifestation of MH?
Increased ETCO2
Increased HR and RR
Muscle rididity
What is a late sign of MH?
Rapid rise in temperature
What is the dose of dantrolene?
2.5mg/kg
What dose of bicarb can be given for acidotic patients with MH?
1-2mEq/kg, maintain pH >7.2
How is hyperkalemia treated in MH?
CaCl 10mg/kg or Ca gluconate 30mg/kg
Regular insulin 0.1u/kg and 1mL/kg D50
How is dantrolene mixed?
20mg vial mixed with 60mL sterile water
How does dantrolene treat MH?
A postsynaptic muscle relaxant that lessens excitation contraction coupling in muscle cells
Inhibits calcium ion release from the SR stores by antagonizing the ryanodine receptors
What characterized emergence delirium?
Postoperative phenomenon of aberrant cognitive and psychomotor behavior
What are clinical manifestation of emergence delirium?
Disorientation
Non purposeful movements
Failure to establish eye contact
Inconsolable
What population is most at risk for emergence delirium?
Children younger than six
Prep anxiety
Rapid emergence from GA
What is the most common cause of bradycardia in the pediatric population?
Hypoxemia until proven otherwise
What are other causes of bradycardia in peds?
Vagal reflexes
Excessive potent anesthetic agent
What is the treatment for bradycardia in pediatric patients?
Administer 100% O2
Stop procedure
IV atropine 0.02mg/kg, if unresponsive 2-10mcg/kg of epinephrine
When should compressions be initiated in pediatric patients with bradycardia?
HR less than 60bpm, infants HR less than 80bpm
What is the appropriate amount of joules a pediatric patient should be shocked with during resuscitation?
2-4j/kg
What is the dose of amiodarone for a pediatric patient?
5mg/kg bolus may repeat x2
What age group is not usually upset by separation from parents prior to surgery?
0-6mos old
What age group is less upset by separation from parents but asks a lot of questions and would like choices?
School aged children
What age group experiences separation anxiety prior to surgery?
6months-4yrs old
What age group fears the process of narcosis and loss of control they also value modesty?
Adolescents
What are NPO guidelines for children?
Clear liquids 2hrs
Breast milk 4hrs
Formula 6hrs
Solid food 8hrs
How frequently is a heart murmur detected in pediatric patients?
Detected up to 50% of pediatric patients
When is it necessary for a heart murmur to be investigated?
Difficulty feeding, SOB
Poor exercise tolerance
Family history CHD
Cyanotic episodes
What labs are indicated prior to surgery for the pediatric population?
Often unnecessary
May consider HH on neonates especially in prematurity
When is it contraindicated to do a mask induction in a pediatric patient?
Full stomach
Difficult airway
Cardiac instability
What types of conditions seen in pediatric patients may indicate a potential unstable cervical spine?
Down syndrome or Marfans syndrome
How much of a IVF bolus is given with pediatric inductions?
10-20mL/kg
At what point would you switch from using a pediatric circuit to an adult circuit?
25-30kg and up use an adult circuit
What contributes to easy airway obstruction of the infants airway?
The tongue is relatively large in proportion to the rest of the oral cavity
Where is the larynx in the pediatric patient compared to the adult patient?
C3-4 compared to C4-5 and seems more anterior
How does the epiglottis of a child differ from an adult?
The epiglottis is narrower, omega shaped and angled away from the axis of the trachea
Often obstructs the view of the vocal cords and is more difficult to lift
Why might the ETT be more difficult to advance through the cords compared to an adult?
Vocal cords have a lower attachment anteriorly, the tip of the ETT can get held up at the anterior portion of the folds
What is the narrowest portion of the child’s larynx?
Cricoid cartilage until about age 8
What can occur if the ETT fits too tightly at the cricoid cartilage?
It compresses the tracheal mucosa at this level may cause edema and result in post extubation croup
Why do pediatric patients have an increased oxygen requirement?
2-3x higher than adults because of increased metabolic rate
How does pulmonary physiology differ in the pediatric patent?
Decreased FRC and Increased closing capacity
Trachea, larynx and bronchi are highly compliant
Why do pediatric patients belly breathe?
Chest wall is more horizontal and pliable which allows for minimal vertical movement
What is used to align the OLP axes in pediatric patients?
Shoulder roll
What is the most common error in mask ventilating a pediatric patient?
Compressing the submental triangle below mandibular ridge
How should we size an oral airway?
Lips to the angle of the mandible
How should we size a nasopharyngeal airway?
The tip of the nose to the tragus of the ear
Why are NPAs often avoided in pediatric patients?
To prevent trauma and bleeding from hypertrophied adenoids
What is the formula for the depth insertion of an ETT?
10 for newborns
11 for 1y/o
12 for 2y/o
Greater than 2y/o tube size times three
What intervention has shifted the thought away from kids under eight should receive uncuffed ETTs?
The replacement of high pressure low volume cuffs with low pressure, high volume cuffs
When should the provider change to a smaller tube after a leak check?
If there is no air leak around the tube below 20-25cm H2O the ETT should be changed to the next half size smaller
What is the perfusion pressure of the tracheal mucosa?
30-40cmH2O, if ETT exerts more pressure than the perfusion pressure ischemia may occur
What air leak is associated with risk for aspiration?
Less than 18cmH2O
What is typically the cause of laryngotracheal (subglottic) stenosis?
Ischemic injury of lateral wall pressure from the ETT
When does granulation begin to form after tracheal ischemia has occurred?
Within 48hrs resulting in narrowing of the airways
When are infants able to convert to oral breathing?
By 5 months of age
How should the cuff of an ETT be inflated for the pediatric patient?
Leak check with 20cmH2O
Why should cuff pressure be checked more frequently in cases using N2O?
N2O can diffuse into the cuff causing an increase in pressure
How can you judge an awake child or infant?
Eye opening
Moves all limbs
Can pull legs to chest
Regular respirations after stimulation
What are two primary factors of low or no cardiac output?
Loss of pulse oximeter and inability to measure blood pressure
What may be happening if the pulse oximeter is still picking up but the BP won’t pick up?
Likely hypovolemia or anesthetic overdose
What is the gold standard for confirming successful endotracheal intubation?
Capnography
What can cause changes on the wave of the capnograph?
Bronchospasm
Endobronchial intubation
Kinked ETT
Low pulmonary blood flow
What can be a problem with capnography in small children?
Inaccuracy of recording especially with high fresh gas flow rates
