Heart rate, Finger clubing, DOTS

1. What is the fastest, most common, efficient way to calculate the heart rate from ECG? (Hint: number 300)

2. How to diagnose finger clubbing and how to stage the finger clubbing? What are the possible cardiovascular causes of finger clubbing? (Hint: one of the test-> diamond window)

3. Once a patient is diagnosed TB, he/she has to follow DOTS. What is DOTS? He/she will given a small recordable TB book and there are 2 kinds of color for it. There will be white and yellow in color. What does the color mean? (Hint: the color has to do with sputum AFB)

1. Calculating heart rate (HR) from ECG

The most common way to calculate HR from ECG is by taking 300 and divide it RR interval (RRI) (represented by number of big boxes).
e.g. The RRI is 4 big boxes, so the HR = 300/4 = 75 beats per min (bpm).

If the patient has very fast HR and the RRI might be less than even 1 big boxes, HR can be calculated by taking 1500 and divide it by RRI (represented by number of small boxes).
e.g. The RRI is 4 small boxes, so HR = 1500/4 = 375 bpm.

However, personally I found out that the fastest and most efficient way to calculate HR is the triplet method. First memorise these 2 triplets:

300-150-100
75-60-50

Then try to find a R wave on a black line, then start counting the black lines after that R wave until u meet the next R wave. When you count, don't count by mentioning "1-2-3-4......", rather you should count by mentioning the triplets that you memorise, i.e. "300-150-100-75.....". So when the number of the black line that you mentioned hit the next R wave, that's the HR. I hope the illustration below helps to understand this concept.

You can make the most out of this triplets method by further memorised the numbers in between those triplets. This become handy when the next R wave falls in between the 2 black lines.

300-200-150-120-100-85
75-65-60-55-50-45

For e.g. when the next R wave falls in between the lines represent 300 and 150, so we can straight away know the HR = 200 bpm.

This method is efficient because it saves the trouble of calculating difficult mathematics, eg 300 divided by1.5 boxes, or 300 divided by 2.5 (either with your mind or with a calculator or the calculator in the handphone).

2. Finger / Digital Clubbing: There are 4 stages of finger clubbing.

1. Increased glossiness and cyanosis at the skin of the root of nail with increased fluctuation at the base of the nail bed. 
2. Lovinbond's sign : loss / reverse of hyponychial angle (angle between nail and nail bed).
3. Hippocratic finger / Parrot beak / Drum-stick: increased anterior-posterior (AP) curvature.
4. Hypertrophic osteoarthopathy (HOA).

• Schamroth's window test: bring the fingers from side together, with the nail facing each other. Loss of the kite-shaped window between the nail indicates finger clubbing.
  
  
  
• Interphalangeal depth ratio: DPD/IPD > 1 indicates finger clubbing.
  DPD : distant phalangeal depth, AP dimension measured at hyponychial angle.
  IPD : interphalangeal depth, AP dimension measured at the distal interphalangeal joint (DIPJ)
  
  
• Elicit fluctuation: I stage of clubbing can be checked by palpating the nail bed with both hands: 2 thumbs below the patient's finger; while 2 index fingers above the patient's finger, near the tip; 2 middle fingers above the patient's finger, at the end of the nail bed. Use your middle fingers to press the nail bed, check whether the distal part of the nail is fluctuating / ballotable.

Summary of the examination for digital clubbing

1. View the fingers from a dorsal and lateral view. Note the width of terminal portion and compare with the proximal part.
2. Look at the angle between the nail and skin (Schamroth's window test)
3. Inspect the periungual skin. Check for cyanosis, shiny, or stretched skin.
4. Elicit fluctuation of the nail bed.
5. Attempt to feel the posterior edge of nail.

Cardiac cause of finger clubbing: infective endocarditis (IE), cyanotic heart disease.

Need to exclude GI and respiratory cause: e.g. liver cirrhosis, bronchial CA.

3. DOTS is Directly Observed Treatment, Short-course. Consists of 5 elements:

1. Government commitment.
2. Detect case with sputum AFB of TB patients.
3. Standard short course of 6/12 TB treatment, with trained supervisor watching patients swallow their anti-TB drugs. DOTS is used with intermittent dosing (thrice weekly). 
4. Regular anti-TB drugs supply.
5. Monitor and report treatment outcome.

Not quite sure about the white and yellow booklet. Anyway this is my guess. Since the patient's sputum AFB need to be checked, so the booklet should be used to record the result of sputum AFB. Since only one booklet is given, and the container for sputum AFB collection is yellow in colour, so the yellow book should be given for patient with smear +ve PTB, while white book should be given to patient with smear -ve PTB. This is just my guess.

--- UPDATE ---

Stage of finger clubbing
I. Fluctuation and softening of finger nail bed
II. Loss of normal angle (Lovinbond's angle)
III. Increased convexity of nailbed
IV. Thickening of whole distal part of finger nail
V. Shiny aspect and striation of nail and skin (HPO)

Causes of FC with CVS origin
1. Artrial myoma
2. Cardiovascular disease with hypoxia
3. Congenital heart disease
4. Infective endocarditis

DOTS is directly observed therapy, short course
What you mentioned about DOTS is right. After a patient is diagnosed TB, he/she needs to come to KK(Klinik Kesihatan) to claim anti-TB medication daily, so that we can make sure the patient is taking medication.
White DOTS book means "smear -ve TB" and yellow one means "smear +ve TB".

Additional question: a senior MO asked me this question.

What are the two types of finger clubbing? (Hint: stage III of clubbing)

Types of finger clubbing:

1. Parrot-beak
2. Drumstick

According to that MO, certain type of clubbing is more common or dominant in certain diseases, due to different pathogenesis or mechanism. He wants me to find the answers myself, but honestly after I searched for few days still can't find the answer. Apparently this information is something that he learnt in India, since he graduated from there, and he asked me to find in Indian website.