Paediatric Anaesthesia Formulas

Transcription

1 Paediatric Anaesthesia Formulas Fluid requirements Fasting Guidelines for Pediatric Patients TYPE Fasting Time (hr) Clear liquids* 2 Breast milk 4

2 TYPE Infant formula 6 Solid (fatty or fried) foods 8 Fasting Time (hr) *Includes only fluids without pulp; clear tea or coffee without milk products. The American Society of Anesthesiologists guideline allows a light breakfast (tea and plain toast) 6 hours before anesthesia; however, determining what a light breakfast means for a child is difficult. Maintenance Requirements in Children Weight (kg) Maintenance Requirements in Children (ml/hour) (ml/kg) (ml/kg) > 20 kg (ml/kg) Replacement of Losses Procedure Non-invasive (inguinal hernia, clubfoot) Mildly invasive (uteteral reimplantation) Moderately invasive (bowel reanastamosis) Significantly invasive (NEC) Insesnsible losses 0-2 cc/kg/hr 2-4 cc/kg/hr 4-8 cc/kg/hr > 10 cc/kg/hr Intraoperative Glucose Infants: 4 mg/kg/min = 240 mg/kg/hr maintenance requirements D5 = 50 mg/ml Delivery of > 4 ml/kg/hr may lead to hyperglycemia Catheter sizes and their flow rates Catheter Size (gauge) Length (inches) Crystalloid (gravity) MEAN FLOW RATE RANGE (ml/min) Crystalloid (pressure) Blood (pressure) to to to to to to to 2 38 to to to to 2 55 to to to to to to 286

3 Catheter Size (gauge) Length (inches) Crystalloid (gravity) MEAN FLOW RATE RANGE (ml/min) Crystalloid (pressure) Blood (pressure) to to to Data summarized from Hodge D III, Fleisher G: Pediatric catheter flow rates. Am J Emerg Med 3:403, Paediatric Airway Equipments Pediatric Endotracheal Tube Size Age Internal Diameter (mm) Depth (cm) Preterm Term months years years years years Pediatric Endotracheal Tube Depth For preemies and neonates (cm) = weight (in kg) + 6 For 1 year or older (cm) = age + 10 cm Pediatric Airway Equipment Age Miller Blade < 32 weeks 00 Term 0 (< 3 kg)

4 3-18 mo. 1 (3-10 kg) > 18 mo 2 (> 12 kg) Pediatric LMA Size LMA sizes ~ weight (kg) / (round to nearest 0.5) Laryngeal mask airway size characteristics Laryngeal Mask Airway Size Approximate Weight (kg) Cuff Volume (ml) 1 <5 2 to to 10 3 to to 20 5 to to to to to to to > Pediatric-sized laryngeal mask airways and compatible endotracheal tubes [*] Laryngeal Mask Airway Size Maximum Lubricated Uncuffed Standard Endotracheal Tube Inner Diameter (mm) Maximum Lubricated Cuffed Standard Endotracheal Tube Inner Diameter (mm) Maximum Flexible Bronchoscope Size [ ] [ ] [ ] [ ] 5.0 Litman RS: The difficult pediatric airway. In Litman RS, editor: Pediatric anesthesia: The requisites, St. Louis, 2004, Mosby. *Based o eperiets perfored the author, As per LMA North Aeria, Largest availale uuffed endotracheal tube available at The Children's Hospital of Philadelphia.

5 Laryngoscope blade types and sizes BLADE TYPE AND SIZE Age Miller Wis-Hippel Macintosh Premature neonate 0 Term neonate 0 to 1 1 to 12 mo to 2 yr to 6 yr to 12 yr 2 3 Endotracheal tube size [*] Age Weight (kg) ID (mm) Length (OT) (cm) Length (NT) (cm) Suction Catheter (F) Premie 0.7 to to Premie 1.0 to to 9 9 to 10 5 Newborn 2.5 to to to mo 3.5 to to to 9 mo 5.0 to to to to to 18 mo 8.0 to to to to to 3 yr 11.0 to 4.5 to to to to 5 yr 15.0 to 5.0 to to to to 7 yr 19.0 to 5.5 to to to to 10 yr 24.0 to 6.0 to to to to to 6.0 to 20 to to yr [ ] 12 to to 6.5 to 20 to to yr [*] 14 to 16 yr 45.0 to to 7.5 [*] 20 to to Data modified from Smith RM: Anesthesia for infants and children. CV Mosby, 1980, St. Louis; Davenport HT: Paediatric anaesthesia. Year Book Medical Publishers, 1973, Chicago. ID, inner diameter; OT, orotracheal tube; NT, nasotracheal tube; F, French size (number is approximately equal to ID 4).

6 * The endotracheal tube should fit so as to allow full normal expansion of both lungs with positive airway pressure ut to perit a gas leak aout the tue at 20 to 25 H2O. Cuffed tue. Recommended nasotracheal tube dimensions TUBE LENGTH (L) (cm) Age (yr) Tube Size (S) (ID, mm) Yates et al. (1987) Rees (1966) Steward (1979) 0 to 3 mo 2.5 to to to 7 mo 3.5 to to to to to to to to to to to to Medications for Children Preoperative Medication in Children PO Nasal IV IM Midazolam mg/kg mg/kg Fentanyl 1-3 ucg/kg Morphine mg/kg Sufentanil ucg/kg Ketamine 2-4 mg/kg 4-6 mg/kg Resuscitation Medication in Children

7 Epinephrine = ucg/kg for arrest (100 ucg/kg in ETT), 1-4 ucg/kg for hypotension Atropine = mg/kg (0.3 mg/kg in ETT) - actual dose mg Adenosine = 0.1 mg/kg (max dose 6 mg) Lidocaine = mg/kg SCh = 2-3 mg/kg Rocuronium 1 mg/kg Calcium chloride = mg/kg (dilute to 10 mg/cc or else veins will sclerose, try to give centrally if possible) Bicarbonate = 1 meq/kg (dilute to 1 meq/cc or else veins will sclerose) Naloxone = 0.1 mg/kg DEFIBRILLATION = 2 J/kg (can increase up to 4 J/kg) Preoperative Medication in Children Midazolam mg/kg IV (0.5-1 mg/kg PO, 15 mg max) Methohexital 1-2 mg/kg IV (25-30 mg/kg PR, 500 mg max) Ketamine 1-2 mg/kg IV, 10 mg/kg IM, 5-8 mg/kg PO Sodium Pentothal 1-2 mg/kg IV (separation), 4-6 mg/kg IV (induction) Propofol mg/kg IV (separation), 2-4 mg/kg IV (induction) Etomidate mg/kg IV Antibiotic Doses in Children Cefazolin 25 mg/kg q6-8h up to 1-2 grams Cefotaxime mg/kg q6h Ampicillin mg/kg q6h up to 3 grams Gentamicin mg/kg q8h (must monitor serum levels, longer interval in renal impairment) Clindamycin 5-10 mg/kg q6-8h up to 900mg Mezlocillinn mg/kg q6h up to 2g Vancomycin 10 mg/kg q6h up to 1g Other Useful Medication in Children Glycopyrrolate 0.01 mg/kg IV, IM, ETT (max 0.4 mg) Morphine mg/kg IV (max 0.4 mg/kg) Fentanyl 1-5 ucg/kg IV Ketorolac 0.5 mg/kg IV Tylenol 20 mg/kg PO, 40 mg/kg PR Zofran mg/kg Droperidol ucg/kg Dexamethasone mg/kg for pain, N/V prophylaxis Neostigmine 0.07 mg/kg Dexamethasone mg/kg for tracheal edema Solumedrol 1 mg/kg IV

8 Characteristics of volatile anesthetics MAC (%) Infant (1 to 6 mo) Child (3 to 10 yr) Adult Halothane Enflurane 1.6 Isoflurane Desflurane Sevoflurane Adapted in part from Jones RM: Desflurane and sevoflurane; inhalation anesthetics for this decade? Br J Anaesth 65:527, Copyright The Board of Management and Trustees of the British Journal of Anaesthesia. Reproduced by permission of Oxford University Press/British Journal of Anaesthesia. Intravenous dosage of opioids in children Drug As Major Anesthetic As Adjunct As Postoperative Analgesic Morphine 2 to 3 mg/kg 0.05 to 0.1 mg/kg per hr 0.05 to 0.1 mg/kg Fentanyl 50 to 100 mcg/kg 1 to 3 mcg/kg per hr 1 to 2 mcg/kg Sufentanil 10 to 15 mcg/kg 0.1 to 0.3 mcg/kg per hr Alfentanil 150 to 200 mcg/kg 1 to 3 mcg/kg per min Remifentanil 0.2 to 1.0 mcg/kg per min 0.1 to 0.4 mcg/kg per min Hydromorphone 5 to 10 mcg/kg 3 to 5 mcg/kg per hr 3 to 5 mcg/kg Intravenous doses of muscle relaxants in children MAINTENANCE ED 95 (mg/kg) Drug Intubation (mg/kg) Bolus (mg/kg) Continuous Infusion (mcg/kg/m) Infants Children Mivacurium 0.2 to to Cisatracurium to

9 Vecuronium 0.05 to Rocuronium 0.8 to to Pancuronium Pipecuronium Nonsteroidal anti-inflammatory drugs (NSAIDs) Drug Age Group Dose (mg/kg) Interval Acetaminophen Preterm Term Load: 20; 15(PO), 20 (PR) q12h >3 mo Load: 20 to 30; 20 (PO) q8h Load: 20 (PO); 15 (PO) q4h 40 (PR), 20 (PR) q6h Diclofenac >1 yr 1 (PO) q8h Ibuprofen >6 mo 10 to 15 (PO) q6h Ketorolac >6 mo 0.25 to 0.5 (IM, IV) q6h Naproxen >6 mo 5 to 10 (PO) q8 12h Celecoxib >1 yr 1.5 to 3 (PO) q12h Regional Anaesthesia I. DOSES OF EPIDURAL ANALGESICS Usual Doses and Infusion Regimens for Epidural Anesthesia in Pediatric Patients Agent Initial Dose Continuous Infusion (Max. Doses) Repeat Injections Bupivacaine, levobupivacaine Solution: 0.25% with 5 µg/ml (1/200,000) <4 mo: 0.2 mg/kg/hr (0.15 ml/kg/hr of a 0.125% 0.1 to 0.3 ml/kg every 6-12 hr of a

10 Agent Ropivacaine Adjuvants Initial Dose epinephrine Dose: <20 kg: 0.75 ml/kg kg: 8-10 ml (or 0.1 ml/year/number of metameres) >40 kg: same as for adults Solution: 0.2% Dose: same regimen in ml/kg as for bupivacaine (see above) Avoid in infants < 6 mo Fentanyl (1-2 µg/kg) or sufentanil ( µg/kg) or clonidine (1-2 µg/kg) Continuous Infusion (Max. Doses) solution or 0.3 ml/kg/hr of a % solution) 4-18 mo: 0.25 mg/kg/hr (0.2 ml/kg/hr of a 0.125% solution or 0.4 ml/kg/hr of a % solution) >18 mo: mg/kg/hr (0.3 ml/kg/hr of a 0.125% solution or 0.6 ml/kg/hr of a % solution Same age-related infusion rates in mg/kg/hr as for bupivacaine (usual concentration of ropivacaine: 0.1%, 0.15%, or 0.2%) Do not infuse for more than 36 hr in infants < 3 mo Select only one additive: Fentanyl: 1-2 µg/ml Sufentanil: µg/ml Morphine: 10 µg/ml Hydromorphone: 1-3 µg/ml Clonidine 0.3 at 1 µg/ml of solution Repeat Injections 0.25% or 0.125% solution (according to pain scores) 0.1 to 0.3 ml/kg every 6-12 hr of a 0.15% or 0.2% solution (according to pain scores) Morphine (without preservatives): µg/kg every 8 hr Recommendations for dosing caudal and epidural blocks. Single-dose caudal Continuous caudal or lumbar epidural catheters Concentration Dose Possible Additives 0.175% to 0.5% 0.75 to 1.25 ml/kg not to exceed 3 mng/kg 0.1% to 0.25% 0.4 ml/kg per hr or 0.2 to 0.4 mg/kg per hr Continuous thoracic epidural 0.1% to 0.25% 0.3 ml/kg per hr or 0.1 to 0.2 mg/kg per hr Epinephrine 2.5 to 5 mcg/ml Clonidine 1 to 2 mcg/kg Morphine 30 to 70 mcg/kg Fentanyl 2 to 5 mcg/ml Hydromorphone 5 to 10 mcg/ml Fentanyl 2 to 5 mcg/ml Hydromorphone 5 to 10

11 mcg/ml Bupivacaine, levobupivacaine, or ropivacaine may be used. Greater concentrations and larger doses should be reserved for levobupivacaine or ropivacaine. Doses and concentrations should be reduced in infants. Children less than 2 years of age who receive morphine centrally require 24-hour monitoring after its delivery. II. SPINAL ANAESTHESIA DOSES Volumes of local anesthetic solutions for peripheral nerve blocks and regional anesthesia in children Block Volume (ml/kg) Axillary 0.2 to 0.5 Interscalene 0.33 Sciatic 0.15 to 0.2 Femoral 0.5 Intravenous 0.5 to 10 Caudal 0.5 to 1.0 Intrapleural (infusion) 0.5 (per hr) Usual Doses of Local Anesthetics for Spinal Anesthesia in Neonates and Former Preterm Neonates Younger than 60 Weeks of Preconceptual Age (up to a Weight of 5 kg) Local Anesthetic Dose (mg/kg) Volume (ml/kg) Duration (min) Tetracaine 1% Tetracaine 1% with epinephrine Bupivacaine 0.5% isobaric or hyperbaric Levobupivacaine 0.5% Ropivacaine 0.5% Usual Doses of Local Anesthetics for Spinal Anesthesia in Children and Adolescents Local Anesthetic 0.5% Isobaric or hyperbaric bupivacaine 0.5% Isobaric or hyperbaric tetracaine Usual Dose(s) 5 to 15 kg: 0.4 mg/kg (0.08 ml/kg) >15 kg: 0.3 mg/kg (0.06 ml/kg) 5 to 15 kg: 0.4 mg/kg (0.08 ml/kg) >15 kg: 0.3 mg/kg (0.06 ml/kg) 0.5% Isobaric levobupivacaine 5 to 15 kg: 0.4 mg/kg (0.08 ml/kg)

12 Local Anesthetic Usual Dose(s) kg: 0.3 mg/kg (0.06 ml/kg) >40 kg: 0.25 mg/kg (0.05 ml/kg) 0.5% Isobaric ropivacaine 0.5 mg/kg (max 20 mg) III. RECOMMENDATIONS FOR DOSING OF PERIPHERAL NERVE BLOCKS Recommended Volumes of Local Anesthetic for Single-Shot Upper Limb Blocks with Neurostimulation by Patient Weight Patient Weight Conduction Block 10 kg kg kg >60 kg Brachial plexus above clavicle Brachial plexus below clavicle Any nerve trunk at elbow Any nerve trunk at wrist 1 ml/kg 0.5 ml/kg 10 ml ml/kg 5 ml ml/kg 20 ml ml/kg above 30 kg 10 ml ml/kg above 30 kg 30 ml 15 ml 0.2 ml/kg 0.15 ml/kg 0.15 ml 10 ml 0.05 ml/kg 0.05 ml/kg 0.05 ml/kg Recommended Volumes of Local Anesthetic for Single-Shot Lower Limb Blocks with Neurostimulation 3-5 ml Conduction Block 10 kg kg kg >60 kg Lumbar plexus (psoas compartment) Femoral Fascia iliaca Proximal sciatic Sciatic in popliteal fossa 1 ml/kg 0.5 ml/kg 1 ml/kg 1 ml/kg 0.3 ml/kg 10 ml ml/kg 5 ml ml/kg 10 ml ml/kg 10 ml ml/kg 3 ml ml/kg 20 ml 20 ml 12 ml ml/kg above 30 kg 20 ml ml/kg above 30 kg 20 ml ml/kg above 30 kg 25 ml 30 ml 30 ml 6 ml ml/kg 12.5 ml

13 Usual Local Anesthetic Infusion Rates with or without Bolus Doses of Either Ropivacaine 0.2%, Bupivacaine 0.125%, or Levobupivacaine 0.15% to 0.2% for Continuous Peripheral Nerve Blocks Techniques Infusion rate Bolus doses Plexus and Proximal Conduction Nerve Blocks * 0.2 ml/kg/hr up to 10 ml/hr 0.2 ml/kg up to 5 ml Axillary and Popliteal Blocks 0.1 ml/kg/hr up to 5 ml/hr 0.1 ml/kg/hr up to 3 ml/hr Maximum bolus doses per hour 3 3 Regional Technique Bolus Dose (mlμ/kg) [*] Continuous Infusion (mlμ/kg per hr) Axillary Parascalene 0.2 to to to to 0.2 Femoral or lateral femoral 0.3 to to 0.3 cutaneous Fascia iliaca 0.5 to to 0.3 Lumbar plexus 0.5 to to 0.3 Sciatic 0.3 to to 0.3 Ilioinguinal/iliohypogastric 0.25 NA Penile block 0.1 NA Paravertebral to 0.25 NA, not applicable. Bupivacaine, levobupivacaine, or ropivacaine may be used. For bolus dosing, lower concentrations such as 0.2% to 0.25% should be used in infants and young children, whereas concentrations of 0.375% to 0.5% should be used in children >5 to 8 years of age. For continuous infusions, lower concentrations such as 0.1% to 0.2% of all agents are acceptable Ref: 1. SMITH'S Anesthesia for Infants and Children, Seventh Edition. 2. Miller's Anesthesia - 8th ed.