Catheter Balloon-tipped

Note Balloon angioplasty is a noninvasive procedure in which a balloon-tipped catheter is introduced into a diseased blood vessel. As the balloon is inflated, the vessel opens further, allowing for placement of a stent and improved flow of blood.]... 

Cardiac output, pulmonary artery pressure (PAP) and stroke volume are measured by a thermodilution technique using a Cardiac Output Computer (Gould/Statham SP 1245) and a balloon-tip triple lumen catheter (Gould SP 5105, 5F) with the thermistor positioned in the pulmonary artery via the jugular vein. 

The left ventricular (LV) end-diastolic pressure is set at 10 mm Hg, utilizing a water-filled balloon-tipped catheter attached to a pressure transducer. Baseline hemodynamic measurements are recorded on a strip-chart recorder (Hewlett-Packard 7754A) for a 10-min stabilization period. 

Pulmonary artery occlusion pressure—It is usually determined by a balloon-tipped Swan-Ganz catheter that is advanced into a distal branch of the pulmonary artery. Inflation of the balloon at the catheter tip occludes the pulmonary artery and allows measurement of the left atrial pressure which reflects the left ventricular diastolic pressure. Therefore, it is a measure of the left ventricular preload. 

Once venous access is obtained, the pacing catheter must be placed into the appropriate intracardiac position to begin pacing. A variety of leads that range from 3 to 6Fr in diameter can be nsed for transvenous temporary pacing. Balloon-tipped flotation electrode catheters nse vascular and intracardiac blood flow to direct them into the right ventricle. Balloon-tipped pacing catheters are very pliable and are also available with preformed curvature to facilitate placement from the femoral vein. Traditional temporary electrode catheters are relatively stiff, and must be placed in the ventricle with the aid of fluoroscopy. Traditional electrode catheters come in a variety of shapes... 

One such catheter, a balloon-tipped catheter, is used to open a blocked artery. When the catheter with a balloon fitted on its tip reaches the site of a blockage, the balloon is inflated to enlarge the interior of the artery by flattening plaque deposits s ainst the vessel wall. In 1977, German cardiologist Andreas Gruentzig performed the first balloon angioplasty in a human in Zurich, Switzerland. 

The basic equipment required for the CT colonography examination is little more than a red rubber catheter with a hand held insufflation bulb similar to that used for barium enema examinations. There are a variety of rectal catheters available of varying size, typically 5-15 mm in diameter. Although we routinely use a balloon-tipped enema catheter, many researchers now avoid balloon insufflation. Traditionally room air has been the gas of choice for colonic insufflation at CT colonography due to its availability and lack of additional expense. However, there is a growing body of evidence advocating the use of carbon dioxide (COj) which is associated with less abdominal cramps and is more rapidly reabsorbed (Yee and Galindo 2002). COj is supplied from a refillable cylinder via a disposable administration set which allows constant gas pressure influx with the facility to record both gas pressures and the volume of COj administered. 

Fig. 11.4. a Oesophageal adenocarcinoma Injection of contrast through the catheter (arrow) shows the typical distal oesophageal stricture (arrowheads). The extent is indicated by paperclips on the patient s skin, b A stiff wire has been inserted deep into the stomach (arrowheads) and the catheter is removed, c A Boubella anti-reflux stent with a balloon tip inflated with contrast (arrowheads) is inserted. Note the gap in the delivery sheath between the balloon and the distal end of the stent, which contains the anti-reflux valve and a retrieval string with a metal marker (arrow), d The stent is inserted a little too far and the distal basket deployed (arrowheads). Note the middle stent marker (arrow), which needs to be above the upper end of the stricture, e The part-deployed stent is then pulled back into final position. The deflated balloon tip is just seen in the stomach (arrowheads), f Immediate appearance after stent release... 

Hywel Davies reported of temporarily treatment of aortic regurgitation with a parachute valve mounted onto a catheter tip in 1965 (34). Twenty-seven years later Andersen and his colleagues described the first experience with a bioprosthetic valve attached to a wire-based stent and mounted on a balloon valvuloplasty catheter (35). In 2002, Alain Cribier performed the first transcatheter valve implantation in an elderly patient with inoperable aortic stenosis using a prototype of a stent-mounted, pericardial, tricuspid aortic valve (36). 

Figure Ic. With catheter in place balloon is inflated to block blood flow and catheter tip freezes damaged tissue.

Figure 4 Balloon angioplasty with and without stent deployment, (a) In balloon angioplasty, a thin catheter is threaded through the circulatory system until the uninflated balloon at its tip penetrates the diseased artery at the point of blockage, as shown in the top diagram. The balloon is then inflated to expand the artery, as shown in the middle, before being deflated and withdrawn to allow blood flow to resume (bottom panel). (b) An increasingly common feature of angioplasty involves deployment of an expandable wire structure to help keep the artery from collapsing after the balloon is withdrawn. The procedure is the same as in (a), except that a wire stent is placed over the balloon before insertion (top). The stent expands when the balloon is inflated (middle) and retains its expanded form after the balloon and catheter are withdrawn (bottom), remaining in place after the procedure is complete to provide a permanent structural support for the arterial wall.

If occlusive coronary sinus venography is performed, care must be exercised to assure the relatively stiff tip of the balloon catheter does not engage a small lateral branch vessel or dissect the wall of the coronary sinus before balloon... 

Fig. 16.14 Dislodgment of newly implanted atrial and ventricular pacemaker leads (white arrows) during placement of a Swan-Ganz catheter (black arrow). Both leads are looped up into the right internal jugular vein (white arrowhead) revealing the mechanism of dislodgment the balloon at the tip of the Swan-Ganz catheter was left inflated while it was pulled back towards the venous sheath.

Perhaps the simplest catheter is a thin plastic or rubber tube, for example a standard 14F rectal tube (Jacques Nelaton rectal catheter Rusch, Bucks, UK) or a Foley catheter. The former was shown to be as effective as a standard inflatable rectal balloon catheter (Trimline DC E-Z-EM, Westbury, NY) for achieving adequate distension (Taylor et al. 2003). Alternatively, the Foley catheter is almost ubiquitous and can be used effectively when attached to a bulb insufflator. The soft tip allows safe insertion and it... 

Automated insufflation systems demand specific tubes which are designed to simply plug into the front of the device. Even here there is a choice of both standard larger bore balloon catheter and the slimmer so-called paediatric tip. In our experience, insertion of the larger catheters is, for many patients, the most uncomfortable part of the study. In response to this, the manufacturers have recently developed thin balloon catheters. 

Hydraulic mechanisms have also been used to control the bending motion of the catheter, where positioning of the catheter in a blood vessel is realized by varying the size of inflatable balloons installed at the tip of the catheter [2]. The balloons are inflated individually using electro-thermally controlled microvalves and the degree of catheter bending is controlled by the size of the balloons [2]. This mechanism is cumbersome and controlling the microvalves is slow hence it is not suitable for many applications. 

This technique can be used to form metallic electrodes on catheter tips and balloons as well as on flexible sheets which can contour to body surfaces. 

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