Venous placement

Central PN refers to the administration of PN via a large central vein, and the catheter tip must be positioned in the vena cava. Central PN allows the infusion of a highly concentrated, hypertonic nutrient admixture. The typical osmolarity of a central PN admixture is about 1500 to 2000 mOsm/L. Central veins have much higher blood flow, and the PN admixture is diluted rapidly on infusion, so phlebitis is usually not a concern. Patients who require PN administration for longer periods of time (greater than 7 days) should receive central PN. One limitation of central PN is the need for placement of a central venous catheter and an x-ray to confirm placement of the catheter tip. Central venous catheter placement may be associated with complications, including pneumothorax, arterial injury, air embolus, venous thrombosis, infection, chylothorax, and brachial plexus injury.1,20... 

Patients receiving central PN are at increased risk of developing infectious complications caused by bacterial and fungal pathogens.1,50 Infections maybe related to placement of a central venous catheter, contamination of a central venous catheter or... 

Mechanical complications of PN are related to catheter placement and the system and equipment used to administer PN. A central venous catheter must be placed by a trained professional, and risks associated with placement include pneumothorax, arterial puncture, bleeding, hematoma formation, venous thrombosis, and air embolism.1,20 Over time, the catheter may require replacement. Problems with the equipment include malfunctions of the infusion pump, intravenous tubing sets, and filters. 

An important overall approach for treatment of sepsis is goal-directed therapy. Mortality can be reduced by early placement and use of a central venous catheter, increased fluid volume administration, dobutamine therapy if needed, and red blood cell transfusion, to achieve specific physiologic goals in the first 6 hours. Evidence-based treatment recommendations for sepsis and septic shock from the Surviving Sepsis campaign are presented in Table 45-3. 

The increased risk of thromboembolism associated with atrial fibrillation and with the placement of mechanical heart valves has long been recognized. Similarly, prolonged bed rest, high-risk surgical procedures, and the presence of cancer are clearly associated with an increased incidence of deep venous thrombosis and embolism. Antiphospholipid antibody syndrome is another important acquired risk factor. Drugs may function as synergistic risk factors in concert with inherited risk factors. 

Second- or third-degree burns greater than 10%-20% TBSA or patients with significant smoke inhalation injury will require fluid resuscitation. Peripheral IV catheters can be used, but placement of a central venous catheter is optimal. An indwelling urine catheter should be placed so that output measures can he used to monitor the status of fluid resuscitation. 

One form of monitoring that may take place in the emergency and operating rooms, as well as in the ICU, requires placement of a central venous pressure (CVP) line. Monitoring of CVP provides the clinician with an indirect and insensitive yet useful estimate of the relationship between increased right atrial pressure and cardiac output. ... 

Central catheter site of procedure (bedside vs. operating room), radiographic confirmation of placement, supplies used for site care Peripheral line nursing time, supplies used for site care Routine laboratory and clinical measurements, changes in therapy to prevent complications or toxicities, nutrition support clinician time Mechan/ca/ treatment of specific complication Infectious cost of antibiotic therapy or venous access replacement Metabolic increased clinical and laboratory measurements, possible waste of PN solution... 

C. Secure venous access. Antecubital or forearm veins are usually easy to cannulate. Alternative sites include femoral, subclavian, internal jugular, or other central veins. Access to central veins is technically more difficult but allows measurement of central venous pressure and placement of a pacemaker or pulmonary artery lines. 

FIGURE 61.6 Lymph flow rates in a prenodal afferent lymphatic draining the hind leg as a function of the frequency of a periodic surface shear motion (massage) without (panels a, b) and with (panels c, d) elevation of the venous pressure by placement of a cuff Zero frequency refers to a resting leg with a lymph flow rate, which depends on pulse pressure. The amplitudes of the tangential skin shear motion were 1 and 0.5 cm (panels a, b) and 1 cm in the presence of the elevated venous pressure (panels c, d). Note that the ordinates in panels c and d are larger than those in panels a and b. (From Ikomi E, Hunt J., Hanna G. et al. 1996. /. Appl Physiol 81 2060.)... 

Lead removal is reasonable in patients with ipsilateral venous occlusion preventing access to the venous circulation for required placement of an additional lead, when there is no contraindication for using the contralateral side... 

Removal of noninfected leads is not indicated (Class III) if patients have a life expectancy of less than 1 year and in patients with known anomalous placement of leads through structures other than normal venous and cardiac structures (e.g., subclavian artery, aorta, pleura, atrial or ventricular wall, or mediastinum) or through a systemic venous atrium or systemic ventricle. Additional techniques including surgical backup may be used if the clinical scenario is compelling. 

Oderich GS, Treiman GS, Schneider P et al (2000) Stent placement for treatment of central and peripheral venous obstruction A long-term multi-institutional experience. J Vase Surg 32 760-769... 

Known anomalous placement of the lead through structures other than the normal venous and cardiac structures (e.g., subclavian artery, pericardial space). 

Dinkel H-P, Triller J (2002) Pulmonary arteriovenous malformations embolotherapy with superselective coaxial catheter placement and filling of venous sac with Gug-lielmi detachable coils. Radiology 223 709-714... 

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