Random APLS equations

Question 1

Corrected Na in DKA

Answer 1

Corr Na = Measured Na + [0.3 x (serum glucose - 5.5)] mmol/L

Question 2

Average age for weight formula

Also equation for 0-12 months

Answer 2

Weight = (age + 4) x 2
*in years

0-12 months: weight = ( 0.5 x age in months) + 4

Question 3

Uncuffed tracheal tube for age >1year

1. Internal diameter
2. length of oral tube
3. length of nasal tube

Answer 3

1. interna diameter (mm) = (age/4) +4
2. length (cm) = (age/2) + 12
3. length (cm) = (age/2) + 15

Question 4

Neonate internal tube diameter of tracheal tube

Answer 4

3-3.5mm

Question 5

Cuffed tracheal tube Internal diameter from 2 years

Answer 5

Internal diameter (mm) = (age/4) +3.5

Question 6

Serum osmolality

Answer 6

serum osmolality = (Na x 2) + glu + urea

Normal (270-295 mmol/L)

Question 7

Average age for weight formula

Answer 7

Weight = (age + 4) x 2

*in years

Question 8

Uncuffed tracheal tube for age >1year

1. Internal diameter
2. length of oral tube
3. length of nasal tube

Answer 8

1. interna diameter (mm) = (age/4) +4
2. length (cm) = (age/2) + 12
3. length (cm) = (age/2) + 15

Question 9

Neonate internal tube diameter of tracheal tube

Answer 9

3-3.5mm

Question 10

Cuffed tracheal tube Internal diameter from 2 years

Answer 10

Internal diameter (mm) = (age/4) +3.5

Question 11

Serum osmolality

Answer 11

serum osmolality = (Na x 2) + glu + urea

Normal (270-295 mmol/L)

Question 12

Fluid requirement in Burns (>10%)

Answer 12

in first 24 hours (first half given in first 8 hours). Hartmanns
Percentage of burn x weight (kg) x 4

subsequent therapy guided by urine output.
1ml/kg/h (range 0.5-2)

Question 13

Cerebral perfusion

Answer 13

CPP = MAP - ICP