When they say blood pressure is 100 mmHg, that really means 100 mmHg higher than atmospheric pressure. It's a gauge pressure, not an absolute pressure. The corresponding absolute pressure would be about (760 + 100) mmHg.

^{Originally posted by Georg in a comment}

When they say blood pressure is 100 mmHg, that really means 100 mmHg higher than atmospheric pressure. It's a gauge pressure, not an absolute pressure. The corresponding absolute pressure would be about (760 + 100) mmHg.

^{Originally posted by Georg in a comment}