April 25 (Reuters) - ResMed beat Wall Street estimates for quarterly profit on Wednesday due to strong demand for its sleep apnea devices, sending shares 9% higher in extended trading.

The California-based company reported adjusted profit of $2.13 per share for the quarter ended March 31, compared with average analysts' estimate of $1.91 per share, according to LSEG data.

ResMed makes ventilators and machines that provide continuous and bilateral positive airway pressure - known as CPAP and BIPAP - and they are used for non-invasive treatment of sleep apnea, a condition in which the airway gets blocked multiple times while sleeping.

Rival Philips is facing a years-long halt in sales of its machines until certain improvements are made in its Respironics plant in the United States, bolstering ResMed's market position.

Resmed's sales rose 7% to $1.2 billion, narrowly beating estimates of $1.17 billion.

(Reporting by Unnamalai L in Bengaluru; Editing by Alan Barona)