A machine that does the work both of the heart (pump blood) and the lungs (oxygenate the blood). Used, for example, in open heart surgery. Blood returning to the heart is diverted through the machine before returning it to the arterial circulation. Also called a heart-lung machine. John H. Gibson invented the heart-lung machine which was first successfully used in open-heart surgery in 1953.
- Punch biopsy
A biopsy that is performed by using a punch, an instrument for cutting and removing a disk of tissue. For example, a punch biopsy of the skin may be done to make a diagnosis of skin cancer.
- Puncture wound
An injury that is caused by a pointed object that pierces or penetrates the skin. Puncture wounds carry a danger of tetanus.
- Puncture, lumbar
A procedure in which cerebrospinal fluid is removed from the spinal canal for diagnostic testing or treatment. Abbreviated LP. The patient usually lies sideways for the procedure, although LPs in infants are often done upright. After local anesthesia is i
The opening of the iris. The pupil may appear to open (dilate) and close (constrict), but it is really the iris that is the prime mover; the pupil is merely the absence of iris. The pupil determines how much light is let into the eye. Both pupils are usually of equal size. If they are […]
- Pupil dilation test
An procedure that enables an eye care professional to see more of the retina, the light-sensitive layer of tissue at the back of the eye. Dilating (widening) the pupil permits the retina to be examined for signs of disease. To do this, drops are placed into the eye to dilate the pupil. After the examination, […]