Paediatrics Flashcards
Where does spinal cord end in children as compared to adults? (3)
• Premature infants: L2-L3
• newborns: L3
. Adults: L1
Name 7 factors that increase the risk of intraventricular haemorrhage in paediatrics
. Decreased oxygen
• increased c02
• increase sodium
• decease haematocrit
• awake airway manipulation
• rapid bicarbonate administration
• changes in blood pressure and cerebral flow
Why are children at high risk of high spinal block?
Lack of lordosis
Why may intubation be difficult in children? (6)
• Short neck
. Large tongue
• larynx high and anterior
• epiglottis long, stiff, u-shaped
• air way funnel shaped, narrowest at cricoid
• May have no or loose teeth
What is best way to intubate children? (4)
• Head in neutral position for ventilation. Head tilt chin lift may cause obstruction (sniffing position)
• use a straight blade
• ETT size uncuffed : premature <1kg 2; 1 kg - 3 months size 3; 3-18 months size 3,5 ; > 18 months =(age÷4) +4 (half a size smaller for cuffed or add 3 instead of 4)
• ETT depth: length at gums or incisors. Premature 8cm, neonate 10cm, thereafter (age ÷2) +12 (add 3cm for naso)
• raised shoulders help
What are children’s cardiac output dependent on?
Relatively fixed. Rely on heart rate. Can’t compensate with stroke volume.
At what age do infants present with physiological anaemia and why?
3 months.
Hbf, which has higher affinity for oxygen, being replaced by hba
How do paediatric patients respond to suxamethonium?
Require higher dose
Which ventilator setting/mode should be used for smaller paediatric patients eg neonates?
Pressure control 16-20 cm H2O because avoids barotrauma
Which ventilator setting/mode should be used for larger paediatric patients eg children?
Volume control tidal volume 5-7 ml /kg because can monitor lung compliance
Most ventilators minimum vt 20ml so make sure child weighs enough. Otherwise use pressure control
What should RR be on ventilator for patient aged 0-12 months?
30-36
What should RR be on ventilator for patient aged 12 months to 2 years?
25-45
What should RR be on ventilator for patient aged 2-6 years?
20-30
What should RR be on ventilator for patient aged 6-12 years?
20-25
How to calculate what minute ventilation should be for paediatric patients?
For first 10 kg, 200 ml/kg
For next 10-15kg, add 150 ml/kg
Then for every Kg there after, add 100 ml/kg
Indication for intraosseous line insertion?
Circulatory arrest or decompensated shock with failure to gain iv access
Name 2 contraindic to intraosseous line insertion
• fracture or vascular injury of that limb
• osteogenesis imperfecta
Name 3 sites an intraosseous line can be inserted
• Proximal tibia: anteromedial surface 2-3 cm below tibial tuberosity
• distal tibia: proximal to medial malleolus
• distal femur: midline, 2-3 cm above external condyle
What premedication should be given to children for uncooperation and separation anxiety
Only if absolutely necessary! Monitor strictly
• midazolam 0,5 mg/kg ( with paracetamol because very bitter taste) po 45 min pre-op (or 0,2 - 0,3 mg/kg nasally 20 min pre-op)
• ketamine 5 mg/kg IM only if very uncooperative
Which agents are preferred for paediatric induction?
• Volatile preferred: sevoflurane with or without n20
• if contraindicated, iv and emla cream (1h preop)
Which maintenance fluids and dose are given to paediatric patients?
• Ringer’s lactate. Only add dextrose 1% if risk hypoglycaemia, otherwise avoid hypertonic solutions! Many complications eg seizures
• maintenance: 421 rule
First 10 kg : 4 ml / kg / h
Next 1o - 2okg: 2 ml / kg / h
For every Kg above 2okg, add 1 ml / kg / h
Formula for maximum allowable blood loss (mabl)? NB
Mabl= EBV (estimated blood vol) x [ ( Hct initial - Hct final/trigger) ÷ Hct mean ]
Formula for blood volume to be transfused?
Weight Kg x increment (desired) in hb (g/dl) x ( 3/ hct of rbc)
Hct RBC =60%
In general 10 ml /kg raise hb by 2 g / dL!
Monitor calcium!
What can be used for post operative analgesia for Paeds? (6)
• regional technique
• Paracetamol 20mg/kg PO
• NSAIDs: diclofenac suppositories
• valaron (tilidine) drops (good option)
• ketamine for severe pain 0,25 mg/kg
• opiates last resort with intense monitoring in ICU
Describe the colds score
Score for child with URTI surgery risk. Higher score = higher risk
Based on current signs and symptoms, onset symptoms, lung disease, device used for airway, Surgery type
How should child with URTI be managed pre and intra op? (6)
• Nebulised beta 2 agonist pre-op
• consider antisialogogue
• nasal decongestant
• avoid airway instrumentation and anything in nose
• chest physio post-op
• glucocorticoids reserved for severe asthma
Avoid sedatives
Tidal volume used for children?
6-8 ml/kg/min (same as adults)
Formula to estimate weight in child?
(Age x2)+9
Oxygen consumption of infants as compared to adults?
VO2 infant: 6,5 to 8,5
VO2 adult: 3,5
Minute volume of infants as compared to adults?
Infants 100-150 ml/kg/min
Adults 70-100
Functional residual capacity of infants as compared to adults?
Same (30 ml/kg)
Dead space of infants as compared to adults?
Infants 2-2,5 ml/kg
Adults 2
PAO2 breathing room air of infants as compared to adults?
Infants 65-85 mmHg
Adults 85-100
paCO2 breathing room air of infants as compared to adults?
Infants 30-36 mmHg
Adults 35-45
ETT size premature babies <1 kg?
Cuffed 1,5
Uncuffed 2
ETT size babies > 1 kg up to 3 months?
Cuffed 2,5
Uncuffed 3
ETT size babies 3-18 months?
Cuffed 3
Uncuffed 3,5
ETT size kids > 18 months?
Uncuffed: (age ÷ 4)+4
cuffed: (age ÷ 4)+ 3 (or half a size smaller)
Depth ETT premature babies?
8 cm
Depth ETT neonates?
10 cm
Depth ETT > 28 days child?
(Age ÷2)+12
Depth nasotracheal tube > 28 days child?
(Age÷2) +15
Why are children at risk of aspiration?
Delayed emptying
Name 5 difficulties that can be expected during attempted paediatric intubation
• Identification of vocal cords more difficult: more anterior airway, larynx hidden behind large tongue
• desaturate, hypoxia, resp failure more quickly: decreased functional residual capacity, increased dead space, increased oxygen consumption and c02 production
• hypoxia leads to bradycardia quickly
• prone to laryngospasm
• upper airway prone to obstruction, blocking access to lower airway due to anatomical differences eg short neck
Name 11 anatomical factors that make the paediatric upper airway more prone to obstruction
• Short neck
• higher larynx
• vocal cords slant anteriorly
• epiglottis floppy
• large tongue
• occiput large and round , flexing head forward when supine
• larynx and tracheal cartilage soft and easily compressed
• narrow cricoid
• short trachea
• adenoids and tonsils fill past pharynx
• baby teeth can loosen
Name 5 advantages cuffed endotracheal tubes
. Better protection against aspiration
• allow higher ventilation pressures with poor pulmonary compliance
• more precise monitoring of ventilation
• provide more accurate tidal volume
• release less pollution from leaking and decrease risk fire
Name 2 disadvantages cuffed endotracheal tubes
• Higher risk plugging smaller lumen with secretions
• suctioning more challenging in because tubes are smaller
Maintenance fluids for children?
Ringers only. Only add dextrose 1% if risk hypoglycaemia
4:2:1 rule
4 ml/kg/h for the first 10 kg
2 ml/kg/h for the next 11-20 kg
1 ml/kg/h for each kg after 20
Name 8 physiological changes in paeds respiratory system
• nose breathers
• limited reserve
• Lower FRC
• minute ventilation rate dependent
• closing volume > FRC
• muscles easily fatiguable
• premature prone to apnoea
• high oxygen consumption (6-8 ml /kg/min): desaturate quickly, hypoxia → bradycardia
Most common cause bradycardia in paeds?
Hypoxia
Is muscle relaxant necessary to intubate children?
Long procedure: yes. If use high dose opioids required that long → bradycardia
Shorter :no. High concentration volatile and opioid good
How long should surgery be postponed in child with bad urti?
4 weeks
Name 3 anatomical cardiac differences in children
• Neonate: less contractile myocardium
• transitional circulation
• non-compliant, relatively fixed cardiac output
Name 4 physiological cardiac differences in children
• rate dependent cardiac output (prone to bradycardia)
• higher relative blood volume
• lower peripheral vascular resistance
• immature SNS and baro receptors
Name 2 renal system differences in children and consequences
•Immature kidney function: glomerular filtration better developed than tubular function (can handle volume loads better than solute loads); decreased clearance drugs
• dehydration poorly tolerated: large surface area relative to weight
Name a hepatic system differences in children and consequences
Immature with decreased function: drugs may accumulate
Name 2 haematological system differences in children and consequences
For survival in hypoxic intrauterine environment:
• HbF higher affinity for 02. Replaced by hba→physiological anaemia at 3 months
• less 2,3 DPG
Name 4 pharmacological differences and considerations in children
• immature renal and hepatic function: caution when drug dosing
• inhalation agents: require higher MAC. Quicker induction due to increased co
• opiates: more sensitive
• muscle relaxants: sux requirements higher
