Ce diaporama a bien été signalé.
Nous utilisons votre profil LinkedIn et vos données d’activité pour vous proposer des publicités personnalisées et pertinentes. Vous pouvez changer vos préférences de publicités à tout moment.

The basics of peds anesthesia [autosaved]

3 082 vues

Publié le

125 slides about the updated topic in pediatric anesthesia,and laparoscopy in pediatrics

The basics of peds anesthesia [autosaved]

  1. 1. Pediatric anesthesiaThe Basics and Beyond Ahmad Abou Leila MD Dr.Roland Kaddoum
  2. 2. Presentation facts and objectives 125 slides(72+53)REVIEW the Peds anesthesia basics Updated Basics Some of the SVI mission in Egypt
  3. 3. Infants are not small adults
  4. 4. Different Anatomy Different PhysiologyDifferent Pharmacology Different psychology
  5. 5. Different Approach and preparationBetter understanding of peds anesthesia principles
  6. 6. The different Physiology
  7. 7. Limited blood volume 80ml/kg(full term)Limited stroke volume
  8. 8. CO=SV x HR
  9. 9. CO=SV x HRHigh Heart Rate to maintain CO
  10. 10. The parasympathetic system is mature in newbornsDominant Vagotonic50% of apparently healthy babies24 hours EKG recordingHave shown rhythm changes resembles complete 2:1 Block
  11. 11. Anything causes bradycardiaHypoxia,hypothermia,laryncoscopyAffect the CO
  12. 12. Pediatric Fundamentals – Heart and Circulation Normal heart rate Age (days) Rate 1-3 100-140 4-7 80-145 8-15 110-165 Age (months) Rate 0-1 100-180 1-3 110-180 3-12 100-180 Age (years) Rate 1-3 100-180 3-5 60-150 5-9 60-130 9-12 50-110 12-16 50-100
  13. 13. HIGH HR……..Risk of fatigue compensation LOW afterload
  14. 14. Lowest acceptable SBP=70 + (age x2)
  15. 15. CO can be assessed clinically by stethoscopeHeart sounds become softer and muffled in low CO states
  16. 16. Contractile element is 30% (60%in adults)Starling law is at maximumCannot tolerate volume overload
  17. 17. Thin wall atria and ventricleRisk of tamponade during central line insertion
  18. 18. Born T wave upright in all chest leads In few hours T wave isoelectric or inverted in left chestIn 7 days T wave inverted in the Right chest leads (V1-V4)Failure of T wave inversion in V1-V4 is the earliest sign of RV hypertrophy
  19. 19. Respiratory System
  20. 20. Almost all cardiac arrest due to respiratory problem
  21. 21. Limited AP expansionLimited Lateral expansionVentilation depend on the Diaphragm
  22. 22. Diaphragm in neonates and infants<2y easy fatigue(lacks the Type I muscle fibers )
  23. 23. Any restriction of the Diaphragm movement Results in respiratory difficultiesstomach inflation due to forceful inflation will hinder ventilation
  24. 24. High Risk of barotrauma on MV -PCV
  25. 25. Small lung volume relative to their body size Small FRCHigh RR to maintain the FRCHigh RR on MV
  26. 26. Under general anesthesia, FRC declines by 10-25% in healthy adults 35-45% in 6 to 18 year-olds
  27. 27. General anesthesia, FRC and PEEPPEEP important in children < 3 years essential in infants < 9 monthsMean PEEP to resore FRC to normal infants < 6 months 6 cm H2O children 6-12 cm H2O
  28. 28. Higher O2 Consumption 6ml-7ml/kg Adults (3-4ml/kg) rapid desaturation
  29. 29. Aspiration RiskChildren < 3 years at greater risk of aspiration
  30. 30. No muscle Higher relaxantsincidence of Inadequate GERD anesthesia Short esophagus Limited Excessive air stomach swallowingcompliance during crying Baby trust
  31. 31. 4 hours6 hours8 hours
  32. 32. Encourage water intake within two hours
  33. 33. Less dehydration (better inductionhemodynamic profile)Less agitation and crying Promotes motilityDecrease gastric volume
  34. 34. Neonatal period the HB is HBFHBF has high affinity to O2 ……P50 is ………
  35. 35. HBF decline with ageHBA peaks at 9 month
  36. 36. O2 dissociation curve shifts to the right by acidosis(more delivery)O2 dissociation curve shifts to the left by alkalosis (less delivery)
  37. 37. MV in neonates avoid the hyperventilation induced alkalosis
  38. 38. P50 Hgb for equivalent tissue oxygen deliveryAdult 27 8 10 12> 3 months 30 6.5 8.2 9.8< 2 months 24 11.7 14.7 17.6
  39. 39. Implications for blood transfusion older infants may tolerate somewhat lower Hgb levels at which neonates ought certainly be transfused
  40. 40. Maximal allowable blood loss MABL: EBV x (Hcti-Hctf)/averaage Hct
  41. 41. Neonates have immature WBCs function ..risk of infection is high
  42. 42. Vitamin k dependent factors(II,VII,IX,X) 20-60% of adult values Infants of mother who have received anticoagulation may develop severe bleeding like Vitamin K deficiencyBabies on MV showed significant thrombocytopenia
  43. 43. Large surface area relative to body weight(2-2.5x BW)Thin skin and subcutaneous fat( less insulation)Neonates no shiveringImmature thermoregulation center
  44. 44. Forced air warming systems always availableFluid warmerRoom temperature
  45. 45. Infant kidneysimmature function at birth:  GFR (‘til 2 years old)  concentrating capacity  Na reabsorption  HCO3 /H exchange  free H2O clearance  urinary loss of K+, Cl-
  46. 46. What it means:Newborn kidney has limitedcapacity to compensate forvolume excess orvolume depletion
  47. 47. Maintenance Fluid TherapyTerm Newborn (ml/kg/day) Day 1 50-60 D10W Day 2 100 D10 1/2 NS >Day 7 100-150 D5-D10 1/4 NSOlder Child: 4-2-1 rule
  48. 48. Hourly Maintenance Fluids 4:2:1 Rule4 ml/kg/hr 1st 10 kg +2 ml/kg/hr 2nd 10 kg +1 ml/kg/hr for each kg > 20
  49. 49. Rules 1 Always Use volumetric Chambers or Microdrip (infusion pumps may continue to infusethrough dislodged catheters with out alarm)
  50. 50. Rule 2 Warm up all infused fluid Crystalloids safe up to 54 CBlood safe up to 42 C..risk of hemolysis)
  51. 51. Rule 3Include dextrose in the maintenance hydration fluid (Dextrose 1% or Dextrose 2.5%) Risk of Hypoglycemia is higher in Premature Sick babies(malnutrition,cardiac) Regional anesthesia Glucose infusion
  52. 52. hypoglycemia Apnea CyanosisRespiratory distress Limpness Sweating Seizures
  53. 53. Rule 4Replace Deficits,losses, and bleeding by isotonic fluid (not glucose containing fluid) Risks of Hyperglycemia
  54. 54. Rule 5Monitor intravascular volume closely by BP UOP SVV Heart sounds Warm extremities Capillary refill
  55. 55. Rule 6 Montior electrolytes closelyRisk of Hyponatremia..Na losers Risk of hyperkalemia .. blood transfusion >1-2ml/kg/min
  56. 56. Different anatomy
  57. 57. Short distance between tongue and the glottis Tongue easily obstruct the airway Proximity of tongue to glottis visualization more difficultmore angulation between the oral axis and the laryngeal axis Straight blade preferred more effectively in tongue lift
  58. 58. Epiglottis axis acute angle with airway axis..more difficult to lift Stiff Omega shape ,touch the soft palate(easy airway obstruction)
  59. 59. Large occiput (flexed head) Till one year
  60. 60. Shoulder Roll(deflex the head + stabilize the head) Extreme extension will cause obstruction Head parallel to the ceiling
  61. 61. The narrowest area is…………………………….
  62. 62. MRI at level of cricoid cartilage (notMRI of sub vocal cords area ring)
  63. 63. Bronchoscopy of glottis areaand sub glottis Bronchoscopy of cricoid cartilage
  64. 64. Abide to the rules of ideal tube selection Tube Size Age(yrs)/4 +4(un cuffed) for cuffed tube Age(yrs)/4 +3.5
  65. 65. Subvocal cords area is the narrowest Don’t push the tube through tight glottis opening Prepare smaller tube size
  66. 66. un-CuffedCuffed
  67. 67. Radiologic evidence Airway is oval not circular Clinical evidenceNo difference in incidence of post intubation croup No complications in cuffed tube
  68. 68. Cuffed tubes can be used in kids< 8 years
  69. 69. Neonates have reduced incidence of subglottic stenosis Immature cartilage High water content in cartilage Less susceptible for ischemic injuries
  70. 70. Short NeckShort tracheaRisk of endobronchial Intubation
  71. 71. Airway management Depth of insertion Age/2 + 12 Age (yrs) + 10
  72. 72. Depth of insertion One study used CXR to confirm the correct placement of tube The foot length was accurate as weight based formulas Tube size X 3
  73. 73. Other uses of Tube size Tube size 2 X Tube size=size of NG tube 3 X Tube size =Depth of tube insertion 4 X Tube size =size of chest tube
  74. 74. Intubation using Left molar approach
  75. 75. 1. Left-molar Approach Improves the Laryngeal View in Patients with Difficult LaryngoscopyAnesthesiology. 2000 Jan;92(1):70-4 Full Text 2. Comparative Study Of Molar Approaches Of Laryngoscopy UsingMacintosh Versus Flexitip BladeThe Internet Journal of Anesthesiology 2007 : Volume 12 Number 1 3. The use of the left-molar approach for direct laryngoscopy combined with a gum-elastic bougieEuropean Journal of Emergency Medicine December 2010 ;17(6):355-356
  76. 76. Another anatomical difference Spinal cord ends at L3 In adults it ends at……..Be cautious in neuroaxial anesthesia Lumbar puncture
  77. 77. Epidural or caudal block LOR with saline LOR with air not recommended
  78. 78. Pharmacological difference
  79. 79. More free fraction of medication Greater effect Water soluble Drugs will distribute more Drugs high protein bound Higher loading dose to achieve desired serum Altered protein binding Barbiturates levels High Volume of Distribution Bupivacaine Muscle relaxants Alfentanil Antibiotics Lidocaine Drugs that redistribute to fat Have larger initial peak levels (Opioids) Small proportion of fat and muscles Immaturemetabolism and excretion Delayed Kidney and liver functionsLess muscle mass (more sensitive to muscle relaxants)
  80. 80. Inhalation agents
  81. 81. MAC HIGHER MACHighest MAC in infants 6 months and 1 year
  82. 82. Fast induction
  83. 83. Greater Alveolar High cardiac out Reduced tissueventilation to FRC put to vessel rich blood solubility ratio organs(brain) Fast inhalation induction
  85. 85. When to intubate?
  86. 86. Pediatric psychologyPediatric Perioperative anxiety
  87. 87. 40%-60% of infants experience perioperative anxietyHighest incidence 1-5 years
  88. 88. ConsequencesBad dreams, wake up crying or walking Disobeying parents New onset enuresis
  89. 89. Crying leads to aerophagia and then stomach inflation Higher risk of aspiration and inefficient ventilation
  90. 90. Parental presence induction anesthesia(PPIA) To date the experimental evidence doesn’t support the routine use of PPIA
  91. 91. Pharmacologic intervention superior to other intervention Parent are less anxious
  92. 92. Midazolam is most commonly used(85%)0.5mg/kg PO is the best dose(less side effects , and rapid onset)
  93. 93. Impulsive children shows paradoxicalresponse to Midazolam
  94. 94. Early infancy (neonate to about 7 months of age): Parents are the primary focus Comfortable separation in preop holding area usual
  95. 95. Later infancy to about 5 years: Separation anxiety major Selected parental presenceMidazolam 0.5 mg/kg orally 10 min before separation
  96. 96. >6 years: Child becomes primary focus. Explain exactly what will happen; what you will do Then do it that way. (Be trustworthy!)
  97. 97. Less insufflation pressure6mmHg for infants12mmHg for children
  98. 98. Abdomen insufflation causes vagal stimulation
  99. 99. Abdomen insufflation with Cold CO2Increase the risk of hypothermia
  100. 100. Abdomen insufflationTrend positionHigher risk of endobronchial intubation
  101. 101. Higher risk of HypovolemiaLonger time for bleeding control
  102. 102. Indication for Cuffed ET tubeHigher risk of aspirationAccurate CO2 sampling
  103. 103. Infants < 5 kgPeri-umbilical area shouldn’t be used for port accessRisk of umbilical artery injury
  104. 104. This lecture is posted onwww.anesthesia-resident.blogspot.com
  105. 105. Thank you allAnd have a nice day