Search Histology Slides

Search Our Huge Database of Histo-Slides     



Common Formulae for use in Paeds


Many Drugs are given according to Surface Area of Pt.
Formula to Calculate Surface area from weight (x)  is :

S.A = (4x + 7) / (90 + x)
       = _____ m2

Fluid  rate

what are the formulas to calculate drops rate of a simple dripset, B.T set , and microburette ???

 In in simple drip set 15 drops = 1 ml
 In Blood Tx Set 12 drops = 1ml
 In microdrip set (pediadrip) 60 micro-drops =1 ml

Various Formulae are given below.

 1)   Simple Calculation Formula is:

                    Fluid in ml *drops/time in min

2) Drop index Formula is :

                   Fluid in ml ×drop index/time in min                    

  the drops will come out for one minute !
  drop index is 15 for dripset ,, 60 for M.B (pediadrip) and 10 or BT set.


4) for DRIP.............FLUIDS(ml)/TIME(hrs) MULTIPLY BY 1/4.....e.g to give 500 ml in 8 hrs it will be approx 62 micro drop/min or 15 macrodrops.

Calculation of GFR
Many drugs , specially antibiotics need adjustment in their DOSES, or their INTERVALS of administration . This is decided on the basis of  GFR , which may be calculated as:

GFR = kL/SrCreatinine

Where K is constant
L is length/height
Sr creatinine

K values:

LBW infants in 1st year
Term AGA in first yr
Children and adolescent girls
Adolescent boys

Check at the end of Harriet Lane : Drugs in Renal Failure to see adjustment of DOSES, or intervals or BOTH.

No comments:

Post a Comment