Paediatric anaesthesia

PAEDIATRIC ANAESTHESIA: 

PAEDIATRIC ANAESTHESIA DR .MIZANUR RAHMAN Anaesthesiologist Sher -E- Bangla Medical College Hospital,Barisal

Term: 

Term Neonate-0-1 month Infant-1-12 month Toddler-1-3 yrs Small child-3-8 yrs Large child-8-12 yrs Preterm-<37 wks

Anatomy in paediatric: 

Anatomy in paediatric Non compliant left ventricle Residual fetal circulation Difficult venous and arterial canulation Large head and tongue Narrow nasal passages Anterior and cephalad larynx Long epiglotis Short trachea and neck Prominent adenoids and tonsils Weak intercostal and diaphramatic muscles High resistance to airflow Vocal cords slant anteriorly Large occiput Obligate nasal breath and narrow nares Glottis located at C3 in premature ,C3-C4 in new born,C5 in adults Larynx and trachea are funnel shape

Physiology in Paediatric: 

Physiology in Paediatric Heart rate dependent cardiac output Faster HR Lower BP Faster RR Lower lung compliance Greater chest wall compliance Lower FRC Higher ratio of body surface are to body Wt Higher total body water content Higher closing volume Horizontal ribs , pliable ribs and cartilage Immature baroreceptor reflex , SNS Increased vagal tone

HR , rr: 

HR , rr Neonate-140 , 40 1 yr -120 , 30 3 yrs -100 , 25 12 -80 , 20

Metabolism and Temparature Regulation: 

Metabolism and Temparature Regulation Heat loss due to thin skin ,low fat content , higher surface related to Wt , cold operating room , wound exposure , IV fluid , dry anaes gases , anaesthetic agents Effect-Delayed recovery , cardiac irritability , respiratory depression ,increased pulmonary vascular resistance ,altered drug responses Heat production are nonshivering thermogenesis by metabolism of brown fat shunting of hepatic oxidative phosphorilation to thermogenic proton leak pathway

Renal and GIT function: 

Renal and GIT function Decrease creatinine clearance Impaired Na retention Glucose excretion Bicarbonate reabsorption Poor diluting and concentrating ability High incidence of gastroesophageal reflux Immature liver causes impaired hepatic conjugation

Pharmacology in paediatric: 

Pharmacology in paediatric Immature hepatic biotransformation Decreased protein binding Rapid induction and recovery Increased MAC Large volume of distribution for water soluble drugs Immature neuromuscular junction

Specific Drugs in Paedi Anaesthesia: 

Specific Drugs in Paedi Anaesthesia Inhaltional -Nitrous oxide,Halothane,Isoflurane,Sevoflurane,Desflurane Inravenous-Barbiturates,Propofol,Ketamine,Opioids Muscle relaxant- Succinylcholine,Rocuronium,Mivacurium,Atracurium,Vecuronium Anticholinergics

Anaesthetic Mx: 

Anaesthetic Mx

Preoperative Preparation: 

Preoperative Preparation Prepare the child and family for what is to be expected in the perioperative period Brochures , video tape ,Hospital tour Visited preoperatively by anaesthetist Allowing parents to OT Child is weighted before arrival in OT

Estimation of childrens Wt: 

Estimation of childrens Wt Neonate-3kg 4 months-6kg 1-8 yrs -2*age+9 9-13 yrs-3*age

Laboratory test: 

Laboratory test

Preoperative fasting: 

Preoperative fasting Clear fluid-2 hrs Solid foods or regular formula feedings including breast milk-4 hrs

Premedication: 

Premedication Midazolam-0.3mg/kg, max 15 mg Ketamine-2-3mg/kg Atropine-0.02mg/kg Fentanyl Diazepam

Induction: 

Induction Inhalational(<10 yrs) -70%N2O,30%O2 , Sevoflurane 8% Steal induction - sevoflurane , if child is already sleeping Intravenous(>10 yrs)-TPS-5-7 mg/kg,Propofol-2-3 mg/kg,Ketamine-2-5 mg/kg EMLA cream , Tetracaine gel b4 iv canula

Tracheal Intubation: 

Tracheal Intubation Preoxigenation Elevate the shoulder Uncuffed tube up to 8-10 yrs Tube size-age/4+4 mm id Tube length-age/2+12 cm for oral , age/2+15 cm for nasal Currect size-gas leak at15-20 cm H2O LMA – uswise when muscle relaxant are used Ayres T-piece <20 kg for controlled and spontaneous Minimum gas flow -3L/m FGF-300ml/kg for for spontaneous ,100ml/kg+1000ml for controlled ventilation Guodel airway Transparent Face Mask

Perioperative Fluid Requirements: 

Perioperative Fluid Requirements Maintenance-4:2:1 rule.BSS with or without glucose(LR,D51/2NS,D51/4NS) Estimated fluid deficits- maintenance + hrs last oral intake EBV-Premature-100ml/kg,Neonate-90ml/kg,infant-80ml/kg,>1yrs-70ml/kg ABL-[EBV*(pt hct -lowest acceptable hct )]/average hct Neonate require 3-5mg/kg/min glucose solution 3 rd space loss- o-2ml/kg/hr for atraumatic surgery,6-10 ml/kg/hr for traumatic procedure

Monitoring: 

Monitoring ECG electrode Precordial stethoscope Pulse oximeter Capnography Temparature probe :OT 26’C Arterial cnulation Central venous catheterization UO

Regional anaesthesia: 

Regional anaesthesia Peripheral nerve block-penile block , ilioinguinal block etc Neuroaxial block-Caudal , spinal anaesthesia

Postoperative Complications: 

Postoperative Complications PONV-iv fluid , limiting oral , antiemetics Laryngospasm - oxygen,PPV,jaw thrust ,IV lignocaine (1-1.5mg/kg) , suxa (0.5-1mg/kg) , Rocuronium (0.4mg/kg) , controlled ventilation Stridor - Oxygen ,steroid , racemic epinephrine Emergence agitation – Fentanyl -1-2 microgram/kg , morphine – 0.1mg/kg , meperidine – 0.5 mg/kg , ketorolac 0.5-0.75mg/kg ,rectal acetaminophane -40mg/kg

Reference: 

Reference Clinical anaesthesiology , Edward Morgan Textbook of Anaesthesia , G Smith Anaesthesia Secretes , James Duke Anaesthesia and Intensive Care A-Z

Slide 23: 

THANK YOU ALL