Inferior vena cava syndrome
|Inferior vena cava syndrome|
|Classification and external resources|
Inferior vena cava syndrome (IVCS) is a result of obstruction of the inferior vena cava. It can be caused by invasion or compression by a pathological process or by thrombosis in the vein itself. It can also occur during pregnancy.Pregnancy can lead to problems with blood return due to high venous pressure in the lower limbs, failure of blood return to the heart, decreased cardiac output due to obstructions in inferior vena cava, sudden rise in venous pressure which can lead to placental separation, and a decrease in renal function. All of these issues can arise from lying in the supine position during late pregnancy which can cause compression of the inferior vena cava. Symptoms of late pregnancy inferior vena cava syndrome consist of intense pain in the right hand side, muscle twitching, drop of blood pressure, and fluid retention.
Epidemiological data is elusive owing to the wide variety of clinical presentation. In the U.S., incidence is estimated to be at 5–10 cases per 100,000 per year. Minor compression of the inferior vena cava during pregnancy is a relatively common occurrence. It is seen most prevalently when women lie on their back or right side. 90% of women lying in the supine position during pregnancy experience inferior vena cava syndrome; however, not all of the women display symptoms.
- Obstruction by deep vein thrombosis or tumors (most commonly renal cell carcinoma)
- Compression through external pressure by neighbouring structures or tumors, either by significantly compressing the vein or by promoting thrombosis by causing turbulence by disturbing the blood flow. This is quite common during the third trimester of pregnancy when the uterus compresses the vein in the right side position.
- Iatrogenic causes may be suspected in patients with a medical history of liver transplantion, vascular catheters, dialysis and other invasive procedures in the vicinity
- Budd-Chiari syndrome
IVCS presents with a wide variety of signs and symptoms, making it difficult to diagnose clinically.
- Edema of the lower extremities (peripheral edema), caused by an increase in the blood pressure in the veins.
- Tachycardia. This is caused by the decreased preload, causing the heart to increase its frequency.
- In pregnant women, signs of fetal hypoxia and distress may be seen in the cardiotocography. This is caused by decreased perfusion of the uterus, resulting in hypoxemia of the fetus.
- Supine hypotensive syndrome
- D.B. Scott; M.G. Kerr (1963). "Inferior vena cave pressure in late pregnancy". BJOG. 70: 1044–1049. PMID 14100067. doi:10.1111/j.1471-0528.1963.tb15051.x.
- B. Howard; J. Goodson; W. Mengert (1953). "Supine hypotensive syndrome in late pregnancy". Obstetrics and Gynecology. 1: 371–377. PMID 13055188.
- M.G. Kerr; D.B. Scott; Eric Samuel (1964). "Studies of the inferior vena cava in late pregnancy". British Medical Journal. 1: 532–533. PMID 14101999. doi:10.1136/bmj.1.5382.522.