Medical Encyclopedia P: Medical Terms Explained

Package leaflet

The leaflet enclosed with a medicine, with information on use, dosage, contraindications and side effects.

Painful urination (alguria)

Painful urination, usually a burning sensation in the urethra. A common cause is cystitis, but stones or sexually transmitted infections are also possible.

Pallor

Noticeably pale skin and mucous membranes, for example in anaemia, circulatory weakness, shock or cold. The conjunctiva and nail beds are better for assessment than the facial skin.

Pancreatic cancer

A malignant tumour of the pancreas that often causes symptoms only late and is therefore usually detected late.

Pancreaticoduodenal arteries

Arterial arcades around the head of the pancreas and the duodenum, fed by the coeliac trunk and the superior mesenteric artery. They connect both supply territories.

Paracentesis (ascitic tap)

Puncture of the abdominal cavity with a needle to obtain ascitic fluid for testing or to drain larger amounts for relief. It is diagnostically important in newly developed ascites.

Parietal cells

Cells of the stomach lining that produce hydrochloric acid and intrinsic factor, which is needed to absorb vitamin B12. Proton pump inhibitors act on their acid pump.

Pelvic binder

A wide belt applied at the level of the greater trochanters when an unstable pelvic fracture is suspected. It stabilises the pelvis and can reduce dangerous bleeding.

Pelvic floor

A layer of muscles and connective tissue that closes the pelvic outlet and supports the bladder, bowel and uterus.

Pelvic floor training

Targeted exercises to strengthen the pelvic floor against incontinence and prolapse symptoms.

Pelvic floor weakness

Declining strength of the pelvic floor muscles, for example after childbirth, with age or with obesity. Consequences can be urinary incontinence and prolapse symptoms; targeted pelvic floor training helps many people.

Pelvic fracture

A fracture of a bone of the pelvic ring, in younger people usually from high-speed accidents, in older people from falls. Unstable fractures can cause life-threatening bleeding.

Pelvic inflammatory disease (adnexitis)

Inflammation of the fallopian tube and ovary, usually caused by ascending bacteria such as chlamydia. Untreated, it can lead to infertility.

Pelvis

The bony ring of hip bones and sacrum that connects the spine with the legs and protects the pelvic organs.

Perianal haematoma

A painful, bluish lump at the anus caused by a blood clot; often mistaken for haemorrhoids.

Pericallosal artery

The continuation of the anterior cerebral artery over the corpus callosum, supplying the inner surface of the frontal and parietal lobes. Aneurysms occasionally form at its origin.

Pericardiacophrenic artery

A thin artery from the internal thoracic artery that runs with the phrenic nerve between the pericardium and pleura to the diaphragm.

Peritoneum

The thin membrane lining the abdominal cavity and covering most abdominal organs. Its inflammation is called peritonitis.

Pes anserinus bursa

A bursa beneath the pes anserinus on the inner side of the head of the shin bone. Its irritation causes pain on the inner knee, for example in runners or knee osteoarthritis.

Pharmacy

A facility that dispenses medicines and provides pharmaceutical advice.

Pharmacy-only medicine

Medicines that may only be sold in pharmacies, even if they do not require a prescription.

Phlebotomy (bloodletting)

Deliberate removal of a larger volume of blood from a vein to remove excess iron or too many red blood cells. Today it is used mainly in haemochromatosis and polycythaemia vera.

Physical inactivity

Too little physical activity; the WHO recommends at least 150 minutes of moderate activity per week.

Popliteal artery

The artery behind the knee, continuing from the femoral artery and dividing below the knee into the lower leg arteries. Aneurysms and injuries in knee dislocations can occur here.

Post-acute rehabilitation

Medical rehabilitation that starts immediately or within a few weeks after a hospital stay, for example after a heart attack, joint replacement or cancer surgery. It is usually applied for while still in hospital.

Posterior auricular artery

A branch of the external carotid artery that rises behind the ear and supplies the ear and scalp.

Posterior cerebral artery

The artery from the basilar artery that supplies the occipital lobe, parts of the temporal lobe and the thalamus. Its occlusion often causes loss of half of the visual field in both eyes.

Posterior ciliary arteries

Branches of the ophthalmic artery that enter the back of the eyeball and supply the choroid and optic nerve head. Their occlusion causes anterior ischaemic optic neuropathy.

Posterior circumflex humeral artery

The artery that passes with the axillary nerve through the quadrangular space and supplies the deltoid and shoulder joint. It can be injured in fractures of the humeral head.

Posterior communicating artery

A connecting vessel between the internal carotid artery and the posterior cerebral artery in the circle of Willis. An aneurysm at its origin can press on the oculomotor nerve and cause a dilated pupil with a drooping eyelid.

Posterior inferior cerebellar artery

Usually a branch of the vertebral artery. Its occlusion causes Wallenberg syndrome with dizziness, swallowing difficulties and crossed sensory disturbances.

Posterior intercostal arteries

Paired arteries arising mainly from the thoracic aorta and running along the lower edge of the ribs. This is why pleural taps are performed at the upper edge of a rib.

Posterior tibial artery

The artery running down in the deep calf muscles whose pulse can be felt behind the inner ankle. It supplies the calf and sole; its pulse is checked when poor leg circulation is suspected.

Prepatellar bursa

A bursa between the skin and kneecap that reduces friction when bending the knee. It can become inflamed with frequent kneeling.

Prepatellar bursitis

Inflammation of the bursa in front of the kneecap, often from frequent kneeling, hence also called “housemaid’s knee”. A firm, elastic swelling appears; with redness and fever, bacterial infection must be considered.

Pressure-relieving mattress

A special mattress that distributes or alternates pressure on vulnerable body areas to prevent pressure ulcers.

Primary nursing

A form of nursing organisation in which one nurse is responsible for particular patients throughout their stay, from admission to discharge. It promotes continuity, trust and clear responsibilities.

Primary visual cortex (striate area)

The primary visual cortex in the occipital lobe, where visual input is first processed in the cerebral cortex. Damage on both sides leads to cortical blindness.

Princeps pollicis artery

A branch of the radial artery in the palm that supplies both sides of the thumb. In thumb injuries its course is important for reconstruction.

Prolonged grief disorder

Grief that remains so intense long after a loss that it severely impairs daily life.

Prone positioning

Positioning on the stomach, which in intensive care can improve oxygen uptake in severe lung failure because more lung regions are ventilated. It requires careful padding to protect against pressure damage.

Proper hepatic artery

The artery arising from the common hepatic artery and running with the portal vein and bile duct to the liver hilum. It delivers about a quarter of the liver’s blood but a large share of its oxygen.

Prussian blue (antidote)

Iron(III) hexacyanoferrate, which binds thallium and radioactive caesium in the gut and speeds their excretion. It turns the stool blue.

Prussian blue staining

A stain that makes ferric iron in tissues and cells visible in blue. It is used, for example, to detect iron stores in the bone marrow or ring sideroblasts.

Pulsus bisferiens

A pulse wave with two palpable peaks during the ejection phase. It occurs, for example, in marked aortic regurgitation or hypertrophic obstructive cardiomyopathy.

Pyloric antrum

The lower part of the stomach just before the pylorus. Here food is mixed and passed on in portions; special cells produce the hormone gastrin.

Pain on movement

Pain that occurs during active or passive movement of a joint or body part. It helps narrow down the affected structure during examination.

Parotid duct (Stensen’s duct)

Excretory duct of the parotid gland that runs over the masseter muscle and opens into the mouth opposite the second upper molar. Salivary stones can obstruct the flow here.

Pelvic obliquity

Uneven height of the two sides of the pelvis, for example due to unequal leg lengths, muscle tension or scoliosis. It can contribute to back, hip or knee pain.

Pencil-thin stools

Noticeably thin, pencil-shaped stools. They can indicate narrowing in the rectum, for example due to a tumour, and should be investigated if they persist.

Pericoronitis (difficult tooth eruption)

Difficult eruption of a tooth, usually a wisdom tooth, with inflammation of the surrounding gum. Pain, swelling and restricted mouth opening are typical.

Perineal body

Connective tissue junction in the perineum between the vagina or scrotum and the anus where several pelvic floor muscles attach. Injury during childbirth weakens the pelvic floor.

Perineal tear

Tear of the tissue between the vagina and anus during childbirth, graded into four degrees according to depth. Minor tears usually heal well after stitching; deep tears involving the anal sphincter need careful repair and follow-up.

Periodontal ligament

Connective tissue in the gap between tooth root and bone whose fibres suspend the tooth elastically in the jaw and absorb chewing forces. It contains nerves through which fine pressure differences during chewing are perceived.

Plantar wart (verruca)

Wart on the sole of the foot that grows inwards under body weight and can hurt when walking. It is caused by human papillomaviruses.

Posterior commissure

Cross-connection of nerve fibres at the junction of the diencephalon and midbrain that mediates, among other things, the bilateral pupillary reflex.

Pouch of Douglas

Deepest point of the abdominal cavity between the uterus and rectum (in men between the bladder and rectum). Free fluid, blood or pus collects here first, which is visible on ultrasound.

Pressure bandage

Dressing in which a pad over the wound is firmly fixed with a bandage to stop heavy bleeding. Fingers and toes should still have blood flow afterwards.

Pressure ulcer (bedsore)

Sore in bedridden people caused by sustained pressure; regular repositioning helps prevent it.

Pressure ulcer prevention

Nursing measures to prevent pressure sores, such as regular repositioning, pressure-distributing mattresses, skin checks and encouraging movement. Adequate nutrition and fluids are also part of it.

Pressure-volume loop

Representation of ventricular pressure and volume during a heartbeat as a closed loop. The enclosed area corresponds to the work of the heart; changes show disorders of filling or pumping.

Prevention of sensory deprivation

Measures against lack of stimulation and social isolation in people needing care, such as conversation, activities and sensory stimulation. It helps prevent withdrawal and confusion.

Pterygoid canal

Narrow canal at the base of the pterygoid process of the sphenoid bone that carries the Vidian nerve to the pterygopalatine fossa. This nerve supplies the lacrimal and nasal glands, among others.

Pudendal canal (Alcock’s canal)

Connective tissue tube on the side wall of the ischioanal fossa in which the pudendal nerve and vessels run. Compression here can cause chronic perineal pain.

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