Unless you do a lot of paediatrics, you often don’t think about the dose of blood products by body weight, and they can sometimes be difficult to find.

• Red Cells: 4ml X kg X Hb g/dL rise required. (1 unit/bag ~ 300mL)  
• Fresh frozen plasma: 10 - 20 ml/kg (1 bag ~ 230mL) 
• Cryoprecipitate: 5-10 ml/kg (1 bag ~ 20mL) 
• Platelets: 10ml/kg (1 unit ~ 60mL. 1 pooled bag = 5 units)
• Tranexamic acid: 100mg/kg then 10mg/kg/hr
• Factor 7: 90mcg/kg
• Prothrombin (factor 9) complex: 1mL/kg (25units/kg)

In the exam and even in real life, if you don’t know, then ring someone! (ie: the haemotologist)

PS - To make it easier to remember: FFP, cryo and platelets are all about 10ml/kg.

• 100% oxygen
• Hyperventilate to low normal CO2
• Sedate and paralyse to drop metabolic demand
• Keep warm
• Noradrenaline to improve perfusion of right ventricle
• Nitric oxide

PS -The usual starting dose of nitric oxide is dose 20ppm, which is easy to remember as the usual starting dose of PGE1 is 20ng/kg/min. Neonates with pulmonary hypertension are often on both.

Features of a pulmonary hypertensive crisis:

• These are a nerve wracking emergency
• Patient looks terrible. Pale and blue
• High CVP
• PA pressures nearing systemic pressures
• Decreased lung compliance
• Systemic hypotension
• Hypoxia
• Hypercarbia. Note ET CO2 will be low due to reduced pulmonary blood flow. PaCO2 will be high due to reduced elimination via the lungs
• Acidosis: Metabolic and respiratory 

Other things you can do once the patient is a bit more stable:

• Introduce pulmonary vasodilators: sildenafil, bosantan, phenoxybenzamine, prostacyclin
• get a new echo to see if anything is changed or can be improved

Suction catheter size (French) = Double the ETT size (internal diameter in mm)

For example:

• 3mm ETT = 6Fr sucker
• 4mm ETT = 8Fr sucker
• 6mm ETT = 12Fr sucker

• Difficult airway and other associated abnormalities
• South RAE tube and throat pack
• Nasal airways post op - Repair can cause upper airway obstruction in patients who were breathing though the cleft. Plus tongue can swell with gag
• Arm splints and respiratory monitoring post op

PS - For cleft lip use infraorbital nerve blocks via the mouth: Approach at the intersection of the mucobuccal fold and the junction of premolars 1 and 2. Palpate infraorbital foramen with 2nd finger and use to guide needle. 0.5 to 1ml of local is usually enough. See non-anatomical digram below.

For neonates anatomy is different: Halfway between the midpoint of palpebral fissure and the angle of the mouth.  Bosenberg. BJA 1995; 74: 506-508.

An easy way to remember the maximum dose of local anaesthetic in mililitres is: 1mL/kg of 0.25% bupivacaine/levobupivacaine/ropivacaine.

Surgeons often ask how much they can infiltrate safely and it’s easier to calculate this volume in your head, rather than calculate mg/kg and then convert to volume.

For example, a 15kg child could have up to 15mL of 0.25% bupivacaine, or 7.5mL 0.5% bupivacaine.  

• 100% O2
• Laryngospasm notch pressure
• CPAP or positive pressure ventilation
• Lignocaine on the cords
• Induction dose of propofol
• Suxamethonium IV (1 to 2mg/kg) or IM (4mg/kg)

PS - Laryngeal notch pressure: Firm pressure to the notch behind the earlobe, bounded by the mastoid process, base of skull and condyle of mandible. Pressure on both sides in a cephalad and medial direction can terminate laryngospasm. The jaw should move anteriorly. Mechanism unknown.

Larson C. Anesthesiology. 1998 Nov,(5):1293-4

• Occurs in about 10% of children
• Lasts about 20 minutes
• Characterised by crying, lack of eye contact, non purposeful actions/verbalisations
• Exclude other causes (pain, hypoxia, hypercarbia, hypotension, raised ICP, full bladder)
• Clonidine 1mcg/kg IV works well

PS - Getting parents in to calm a child with emergence agitation is not helpful, as the child is in a dissociated state and will not usually respond. You will just end up with distressed parents too.  

Ultrasound for vascular access in paediatrics can be really useful. The problem is that the distance between the probe and your target might be so small that you can’t see the needle on the screen before it has gone through the target!

To increase this distance put a thick layer of gel on the probe and use a clear dressing to keep it in place. You can almost get an extra 1cm to play with.

PS - Nick the skin with a sharp needle first to avoid tenting at the skin.

Use sterilisation solution (eg alcoholic chlorhexidine) as your interface between probe and skin to avoid getting slippery gel everywhere, which will make your job much harder. 

The magic number to remember is 4. 

4ml/kg of packed red blood cells will give you an increase of about 1g/dL of haemoglobin. 

For example a 9 kg child with an HB of 5g/dL will need 180ml of red cells to reach an HB of 10. (9kg X 4ml X 5g/L = 180ml)

PS - You can use this formula for adults too. 

An easy way to estimate the weight of a child without a formula:

- Term baby 3kg

- 1 year old 10kg

- 5 year old 20kg

Formulae can be hard to remember, especially in paediatrics where most of the terms of the various formulae are similar: Is it age/4+4, or 2(age+4), or 12 + (age/2)? The weight formula 2(age+4)kg is also becoming less accurate as the population becomes heavier and heavier. 

Endotracheal Tube Insertion Depth 

Forget those tricky formulae for uncuffed ETT insertion depth. They are too hard to remember.

Instead, put a size 3mm ETT 3cm at the cords. A size 4 ETT goes 4cm at the cords, etc… The trick is that you need to look at the tube first and follow it down with your eyes as you insert it through the cords, as it´s often hard to see the markings once the tube is in place. If your tube does not have cm markings, measure and draw one in the right spot with a felt-tipped pen first.

Next make sure you note what the distance is at the teeth or the lip so you know if your tube has moved. If you have a cuffed tube, insert so that the cuff is just beyond the cords.