shunt (redirected from portacaval shunt, postcaval shunt)

shunt (shunt)

1. to turn to one side; to bypass.

2. a passage or anastomosis between two natural channels, especially between blood vessels, formed physiologically or anomalously.

3. a surgically created anastomosis; also, the operation of forming a shunt.

---

arteriovenous shunt 

1. the diversion of blood from an artery directly to a vein.

2. a U-shaped plastic tube inserted between an artery and a vein; usually to allow repeated access to the arterial system for hemodialysis.

Blalock-Taussig shunt  see under operation.

cardiovascular shunt  diversion of the blood flow through an anomalous opening from the left side of the heart to the right side or from the systemic to the pulmonary circulation (left-to-right s.), or from the right side to the left side or from the pulmonary to the systemic circulation (right-to-left s.) .

left-to-right shunt  see cardiovascular s.

LeVeen peritoneovenous shunt  continuous shunting of ascites fluid from the peritoneal cavity to the jugular vein by means of a surgically implanted subcutaneous plastic tube.

portacaval shunt  surgical anastomosis of the portal vein and the vena cava.

Shunts diverting portal venous blood flow from the liver. (A), Portacaval shunt; (B), splenorenal shunt.

right-to-left shunt  see cardiovascular s.

splenorenal shunt  removal of the spleen with anastomosis of the splenic vein to the left renal vein.

Shunts diverting portal venous blood flow from the liver. (A), Portacaval shunt; (B), splenorenal shunt.

ventriculoatrial shunt  the surgical creation of a communication between a cerebral ventricle and a cardiac atrium by means of a plastic tube, to permit drainage of cerebrospinal fluid for relief of hydrocephalus.

ventriculoperitoneal shunt  a communication between a cerebral ventricle and the peritoneum by means of plastic tubing; done for the relief of hydrocephalus.

---

shunt (shnt)

n.

A passage between two natural body channels, such as blood vessels, especially one created surgically to divert or permit flow from one pathway or region to another; a bypass.

---

Shunt

A small tube placed in a ventricle of the brain to direct cerebrospinal fluid away from the blockage into another part of the body.

Mentioned in: Cardiac Catheterization, Hydrocephalus

---

shunt

Etymology: ME, shunten

1 to redirect the flow of a body fluid from one cavity or vessel to another.

2 a tube or device implanted in the body to redirect a body fluid from one cavity or vessel to another. See also left-to-right shunt, right-to-left shunt.

---

shunt,

n 1. a hole or passageway that allows the movement of fluid, such as cerebrospinal fluid, from one body part to another. The term is used to describe congenital or acquired shunts, which may be either mechanical or biologic.
2. a surgically implanted tube or catheter, such as those used to treat hydrocephalus, that allows the passage of fluid between body parts.

shunt, arteriovenous,

n (arteriovenous aneurysm, arteriovenous fistula), an abnormal communication between an artery and a vein; usually caused by trauma.

shunt, ventriculoatrial

n a surgically manufactured passage made of plastic tubing between a cardiac atrium and cerebral ventricle for the treatment of hydrocephalus. See also ventriculoureterostomy.

---

shunt

1. to turn to one side; to divert; to bypass.

2. a passage or anastomosis between two natural channels, especially between blood vessels. Such structures may be formed physiologically (e.g. to bypass a thrombosis), or they may be structural anomalies.

3. a surgical anastomosis.

---

arteriovenous (A-V) shunt

a U-shaped or straight tube inserted between an artery and a vein (usually between the radial artery and cephalic vein), bypassing the capillary network; commonly done to allow repeated access to the arterial system for the purpose of hemodialysis.

cardiovascular shunt

an abnormality of the blood flow between the sides of the heart or between the systemic and pulmonary circulation; see left-to-right shunt (below) and right-to-left shunt (below).

left-to-right shunt

diversion of blood from the left side of the heart to the right side, or from the systemic to the pulmonary circulation through an anomalous opening such as a septal defect or patent ductus arteriosus.

LeVeen shunt

a device whose purpose is to remove excess ascitic fluid from the peritoneal cavity and return it to the venous system. Called also peritoneal-venous shunt.

peritoneal-venous shunt

see LeVeen shunt (above).

pleuroperitoneal shunt

a catheter placed to transfer pleural fluid into the peritoneal cavity; requires manual pumping.

portacaval shunt, postcaval shunt

see portacaval shunt.

reversed shunt

right-to-left shunt.

right-to-left shunt

diversion of blood from the right side of the heart to the left side or from the pulmonary to the systemic circulation through an anomalous opening such as septal defect or patent ductus arteriosus.

ventriculovenous shunt

a surgical procedure used in the treatment of hydrocephalus.

---

shunt  

The diversion of the flow of a fluid from its normal pathway to another, which may be accidental, as in a traumatic AV aneurysm, or by design–eg, portocaval shunt or ventriculoperitoneal shunt. See Arteriovenous shunt, Nodovenous shunt, Denver shunt, Distal splenorenal shunt, LeVeen shunt, Perfusion shunt, Portacaval shunt, Transjugular intrahepatic portosystemic shunt Pediatric cardiology Bypassing the pulmonary circulation–shunting is a normal physiologic process in utero; it becomes abnormal after birth Types1. Those in which already oxygenated blood in the left heart passes back into the right heart–left-to-right shunt and 2. Those which partially bypass the lungs, with venous blood directly entering the systemic circulation–right-to-left shunt

Shunt-acyanotic, cyanotic

L→R shunt Acyanotic shunt Right and left sides of the heart communicate by an ASD or VSD and PDA; the blood flows from the region of highest–left heart to lowest–right heart and systemic circulation pressure, as occurs in VSDs and corrected transposition of great arteries; since the blood does not bypass the pulmonary circulation, it is well oxygenated Clinical The plethora of blood causes pulmonary congestion and HTN that becomes significant when the pulmonary blood flow is 1.5-2.0-fold greater than the systemic flow with diastolic overloading and cardiac dilatation which, without correction, results in cardiac failure; a late complication is bacterial pneumonia related to stasis within the pulmonary circulation; L →R shunts may be created surgically–eg, Blalock procedure

R→L shunt Cyanotic shunt Variable degree of pulmonary circulation bypass accompanied by obstruction of blood flow into the pulmonary circulation R→L shunts Fallot's tetralogy–VSD, pulmonary valve stenosis, overriding or dextroposed aorta and 2º right ventricular hypertrophy, transposition of great vessels, tricuspid valve atresia, truncus arteriosus and total anomalous return of pulmonary veins; pulmonary blood flow is less than in L→R shunts Clinical Cyanosis with limited exercise tolerance, neurologic damage and compensatory polycythemia; as children, these Pts are often very sick and by adolescence may suffer acquired coagulopathies