NOCTURNAL HOME PULSE OXIMETRY
O P Kapoor
Ex. Hon. Visiting Physician, Jaslok Hospital and Bombay Hospital, Mumbai,
Ex. Hon. Prof. of Medicine, Grant Medical College and JJ Hospital, Mumbai 400 008.
In the past I have written about pulse oximeter which is an essential instrument and all GPs should possess.
1. It helps in the differential diagnosis of chronic asthma and COPD.
2. Differentiates hysterical dyspnoea from pulmonary embolism3. Helps in evaluating patients of respiratory diseases who need immediate hospitalisation.
I am now mentioning about the use of this instrument in the diagnosis of some other conditions:a. Some patients of chronic congestive cardiac failure develop extra symptoms at night. In the past we usually thought of attacks of LVF or pulmonary embolism. Now we know that cheyne stokes breathing can also cause such symptoms at night. If the SP02 levels fall markedly, the diagnosis is confirmed and these patients are benefited tremendously by CPAP.
b. Sleep apnoea syndrome is too costly to be diagnosed by ‘Poly somnography’ for which the patient is admitted in the hospital and various procedures are done over-night to make the diagnosis. Simpler method is to use nocturnal home oximetery. If during snoring the SP02 falls makedly, the diagnosis of sleep apnoea syndrome is confirmed without spending any money.