Pediatric Preoperative Evaluation

1. Pediatric Preoperative Evaluation

3. Preoperative URI • Intubation increases the risk of these adverse effects Risk is 9 – 11 times greater up to 2 weeks following URI • Decreased O2 Diffusion Capacity • Decreased Compliance • Increased Resistance • Decreased Closing Volumes • Increased Shunting (V/Q Mismatch) • Increased Hypoxemia • Increased Airway Reactivity

4. Preoperative URI • Intubation increases the risk of these adverse effects Increased Risk of • Laryngospasm • Bronchospasm • Postintubation Croup • Atelectasis • Pneumonia • IntraoperativeDesaturation

5. Evaluation of the URI Patient Age Lung Sounds Nasal Secretions (quantity & quality) Spontaneous Cough Fever General Appearance Frequency of Illness / URI

6. Asthma Evaluation of Patient

7. Intraoperative Considerations of the Pediatric Airway

8. Pediatric Airway Obligate Nose Breathers with Narrow Airways Easy Obstruction with Secretions Large Tongue May Obstruct Airway while increasing difficulty of Laryngoscopy & Intubation Large Occiput Place Roll under shoulders Glottis Location C3 premature infants C3-C4 Infants C5 Adults Larynx More Anterior Crocoid Pressure Helpful Larynx & trachea Funnel Shaped Narrowest @ Cricoid ETT leak @ 30 cm H20 Vocal Cords Slant Anteriorly

9. Pediatric Airway Considerations • More anterior than the adult • less head tilt to open the airway • Smaller diameter of airway than the adult • easily blocked by secretions or blood • Large tongue in relation to jaw size • likely to cause obstruction when child is unconscious

10. Breathing Considerations • Small children are dependent on contraction of the diaphragm to breathe. • A child’s primary response to respiratory distress is to increase the rate and effort of breathing.

11. Pediatric Pulmonary Differences Decreased # & Smaller Aveoli • 13 X increase in alveoli between birth and 6 years of age • 3 X increase in size of alveoli Decreased Compliance & Elastin • Atelectasis Smaller Airways & Increased Resistance • Increased Work of Breathing • Atelectasis is significant Less type – 1 / High Oxidative Muscle • Fatigue Sooner Less FRC & TLC • More Rapid Desaturation Higher Closing Volumes • Lower Dead Space Ventilation

12. A child may have pronounced retractions of the chest wall because the chest wall is less muscular and has more flexible bones.

13.  Pediatric Respiratory Rates Age Rate (breaths per minute)  Infant (birth–1 year) 30–60 Toddler (1–3 years) 24–40 Preschooler (3–6 years) 22–34  School-age (6–12 years) 18–30 Adolescent (12–18 years) 12–16 Breathing Considerations A silent chest is an ominous sign of low blood oxygen in the pediatric patient.

14. Oxygenation Considerations • Children compensate efficiently in hypoxemia by increasing heart rate and vasoconstriction but then decompensate rapidly.

15. Pediatric Pulse Rates Age Low High  Infant (birth–1 year) 100 160 Toddler (1–3 years) 90 150 Preschooler (3–6 years)  80 140  School-age (6–12 years) 70 120 Adolescent (12–18 years) 60  100 Bradycardia is a late sign of low blood oxygen in the pediatric patient

16. Low-Normal Pediatric Systolic Blood Pressure Age* Low Normal Infant (birth–1 year) greater than 60* Toddler (1–3 years) greater than 70* Preschooler (3–6 years) greater than 75 School-age (6–12 years) greater than 80 Adolescent (12–18 years) greater than 90 *Note: In infants and children aged three years or younger, the presence of a strong central pulse should be substituted for a blood pressure reading.

17. Pediatric Cardiac Differences • Cannot Increase Contractility • Increase CO by Increasing HR only • Immature Baroreceptor Reflex • Limited Ability to Compensate for Hypotension by increasing HR • Susceptible to Cardiac Depressants (volatile anesthestics) • Increased Vagal Tone • Prone to Bradycardia • Major Causes of Bradycardia • Hypoxia • Vagal Stimulation (laryngoscopy, occulocardiac reflex) • Volatile Anesthetics • Multiple Doses of Succinylcholine

18. Anesthetic Management • Generally have higher drug requirements (mg/kg) because they have a greater volume of distribution • More Fat • More Body Water • Children less than age 1 have increased sensitivity to respiratory depressant effects of opiods

19. Normal Vital Signs by Age

20. Intubation • Picture showing layout of equipment

21. Complications of Intubation • Physiologic • - Hypertension • - Tachycardia • - Laryngospasm • - Intracranial HTN • - Intraocular HTN • Post Intubation Croup • Cuff (Age & Size) • Size of Tube • Malposition • Esophageal • Endobronchial • Trauma • Tooth/Teeth • Lip/Tongue/Mucosa • Sore Throat • Retropharyngeal Dissection • Bleeding (airway prep) • Nasal

22. Choosing the Correct ETT Size Size (Diameter) 16 + Patient Age 4 Length 12 + Patient Age 2 Roughly the size of patient’s pinky finger 3 X the internal diameter of ETT

23. Airway Complications • Laryngospasm • Positive Pressure O2 • Deepen Anesthesia • Succinylcholine • Bronchospasm • Inhaler (partial) • Epinephrine (full)

24. Advanced Airway Devices • ETT Insertion w/ Macintosh Blade • http://www.medicalgeek.com/animations/7886-intubation-animation.html • ETT Insertion w/ Miller Blade • http://www.doereport.com/generateexhibit.php?ID=12137&ExhibitKeywordsRaw=&TL=&A • Laryngeal Mask Airway (LMA) • http://www.doereport.com/generateexhibit.php?ID=12141 • Combitube • http://www.youtube.com/watch?v=MhRj6MLEVoE

25. Fluid Management • Estimated blood Volume • Fluid Management • “4-2-1” Rule • 0 – 10 kg: 4 ml/kg/hr • 10 – 20 kg: 2 ml/kg/hr • > 20 kg: 1 ml/kg/hr Replacement 1st Hour: ½ deficit + maint. 2nd Hour: ¼ deficit + maint. 3rd Hour: ¼ deficit + maint. 4th Hour plus: maint. only

26. PONV • Patient Factors • Age > 6 years • Hx of PONV • Hx of Motion Sickness • Preoperative Nausea • Extreme Preoperative Anxiety • Surgery / Anesthesia Factors • Surgery > 20 minutes • Opiod Use • Nitrous Oxide ??

27. Fever • Usually related to dehydration • Treatment • hydration • Acetaminophen or ibuprofen • Active Cooling Measures • PONV • Dehydration • Pain Postoperative Complications