Untitled

• Pediatric Anesthesia

  Has differing anesthetic requirements. Physiological, anatomic, and pharmacological characteristics of each group
• Age groups in pediatric anesthesia

  • Neonate (0–1 months)
  • Infant (1–12 months)
  • Toddlers (12–24 months)
  • Young children (2–12 years of age)
• Physiological differences in pediatric anesthesia

  • Reduced BP, Increase HR
  • Reduced FRC, Increased RR
  • Increased metabolic rate
  • Limited responses to cold, increased propensity to bradycardia
• Anatomical differences in pediatric anesthesia

  • Larger head, Small mandible, shorter neck, Shorter trachea and High larynx
  • Difficult venous and arterial cannulation
  • Greater resistance to airflow
  • Thin skin
• Pharmacological differences in pediatric anesthesia

  • Immature hepatic biotransformation pathways
  • Decreased blood protein for drug binding
  • More rapid induction and recovery from Inhaled anesthetic
  • Increased minimum alveolar concentration
• Total body water


  • 70-83% of weight in premature babies and neonates
  • 60% of weight in infants
• Estimating pediatric patient's weight based on age

  1. < 1 month ~ 3 kg

  2. 1-12 months ~ (0.5 x age In months) + 4

  3. 1-5 years ~ (2 x age In years) + 8

  4. 6-12 years ~ (3 x age in years) + 7

  5. 12 < years ~ Highly variable
• Jackson Rees modification of the Ayre's T piece


  Breathing system used for children, designed to be lightweight with minimal apparatus dead space, can be used for both spontaneous and controlled ventilation
• Tracheal intubation for children over 1 year

  1. Appropriate tube internal diameter (ID) can be approximately estimated by the formula: age / 4 + 4

  2. Appropriate tube length in cm. can be approximately estimated by the formula: age / 2 + 12 oral (+15 for nasal)

  
• Cuffed tubes

  Generally used only in children above the age of 8 years
• Why prefer un-cuffed tube in Pediatric patients under 8 years
• Laryngeal mask airway (LMA)


  Useful in short procedures with spontaneous ventilation
• Preoperative Assessment for pediatric

  1. Respiratory examination: focus on determining the presence of abnormal air movement

  2. Neurological examination: focus on the child's activity level and note any anomalies

  3. Cardiovascular examination: auscultation of the heart sounds, noting that heart murmurs are common in newborns
• Respiratory examination


  Nasal drainage (clear or discolored yellow/green), cough (dry or productive and color of sputum)
• Respiratory examination


  • Focuses on determining the presence of abnormal air movement, including absent breath sounds, wheezing, or coarse breath sounds
• Neurological examination


  Focuses on the child's activity level and notes any anomalies such as weakness of extremities, or abnormal appearance
• Cardiovascular examination

  Auscultation of the heart sounds, noting that heart murmurs are common in newborns
• Inhalation Induction of Anesthesia


  Has a number of advantages in children, it is painless and successful on the first attempt (whereas intravenous cannulation has failure)
• Intramuscular Induction


  IM injection of ketamine may be the best option in these circumstances
• Intravenous Fluid Requirements


  In fasting children are usually determined using the 4-2-1 rule, the hourly infusion rate is calculated
• Blood Loss Replacement and Transfusion

  Blood loss is replaced with crystalloids (without glucose) or colloid solutions
• Physiological Differences in pediatric

  • Reduced BP, Increase HR
  • The neonate has high responses to cold
  • Reduced FRC, Increased RR
  • Increased metabolic rate
• Pharmacological Differences in pediatric than in adult

  • Increased blood protein for drug binding
  • Immature hepatic biotransformation pathways
  • More rapid induction and recovery from inhaled anesthetic
  • Increased minimum alveolar concentration
• Breathing system used for children

  • Mapleson D and his modification Bain system
  • Mapleson A and his modification Lack system
  • Mapleson B
  • Ayre's T piece and his modification Jackson-Rees
• Anatomical Differences in pediatric than in adult

  • Small mandible
  • Shorter neck Shorter trachea
  • Thick skin
  • Difficult venous and arterial cannulation
• Regional anesthesia


  A local anesthetic given to a specific region of your body, leading to numbness or pain relief for patients to do operations
• Types of regional anesthesia


  • Spinal anesthesia (also called subarachnoid block)
  • Epidural anesthesia (inject in epidural space)
  • Peripheral nerve blocks (bier block)
• Epidural anesthesia


  Anesthesia involves the injection of medication into the "epidural space"
• Advantages of epidural anesthesia


  • Avoidance of Dural puncture
  • Catheter technique, allows control over onset, extent and duration of blockade
  • Used for peri- and postoperative analgesia, analgesia following chest trauma and treatment of chronic pain
  • Selective site and block
• Disadvantages of epidural anesthesia


  • Slower onset of anesthesia in the epidural space
  • Larger volume of local anesthetic is used
  • High risk of local anesthetic toxicity if a vein is entered with the needle or catheter
• Epidural set


  Tuohy needle, Syringe, Epidural catheter, Connecter, Filter
• Methods to detect epidural space


  • The loss of resistance techniques
  • Hanging drop techniques
  • Modern epidural set with EPI detection for monitoring negative pressure
• Anesthetic agents for epidural anesthesia


  • Lidocaine, and mepivacaine for short procedure
  • Bupivacaine 0.5%, levobupivacaine for long procedures
  • Addition of opioid to increase analgesia effect
  • Addition of adrenaline 5 μg/mL to increase duration of epidural anesthesia
• Equipment


  • Epidural set
  • Lidocaine 1.5 %, 5 mL for skin infiltration
  • Lidocaine 1.5 % with epinephrine 1:200,000, 5 mL amp. For epidural test dose
  • Povidone-iodine solution
• Technique


  1. Start a peripheral intravenous line

  2. Position patient in seated, lateral decubitus or sitting position

  3. Prepare the back with povidone-iodine solution

  4. Palpate the spinous processes

  5. Introduce the Tuohy needle into the lower part of the interspace and advance

  6. Attach the glass syringe and continue advancing, checking for loss of resistance

  7. If single shot, inject medication and remove needle

  8. If placing catheter, advance catheter through needle then remove needle

  9. Connect a connector to the end of the catheter and remove the sterile drape

  10. Secure the epidural catheter to the patient's back
• Regional anesthesia


  Spinal anesthesia: injection in subarachnoid space where CSF present to inhibit conduction in nerve roots
• Spinal cord


  • Usually ends at the level of L1 in adults and L3 in children
• Indications for spinal anesthesia


  • Lower abdominal surgery
  • Urogenital surgery
  • Rectal surgery
  • Lower extremity surgery
  • Lumbar spinal surgery

  
• Contraindications for spinal anesthesia


  • Patients refusal and uncooperative patient
  • Bleeding diathesis
  • Severe hypovolemia
  • Elevated intracranial pressure
  • Infection at the site of injection
  • Severe aortic or mitral stenosis
  • Sepsis
  • Prolong operation and major blood loss

  
• Patient positioning for spinal anesthesia


  • Sitting position
  • Lateral decubitus
  • Buies (Jackknife) position