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Em , Niederhuber et al. A retirada fica restrita aos casos em que o cateter perde o fluxo, o que acontece quando a TVP envolve a extremidade do dispositivo Fonte de financiamento: Nenhuma. Access to the venous system is of vital importance for diagnosis and treatment of patients with the most varied range of clinical conditions, whether for taking blood samples or for infusion of solutions.
In , Harvey described the circulatory system on the basis of studies in animals and 4 decades later Sir Christopher Wren conducted the first intravenous infusions in living beings. Since then there has been constant evolution in access technique and infusion devices.
Of particular note is the creation of long-term catheters in the s, particularly totally implantable devices, which revolutionized cancer treatment, increasing both safety and comfort for oncology patients. The objectives of this article are to review historical data on vascular access and discuss the implantation technique and the main complications associated with procedures for placement and use of totally implantable venous access devices.
The physiology of blood vessels began to be revealed in the seventeenth century when Harvey, who conducted experiments with animals, published a description of the circulatory system in the work Excercitatio Anatomica de Moto Cordis et Sanguinus in Animalibus. In , Robert Boyle and in , Richard Lower described blood transfusions from animals to humans. Access to the venous system by puncture was pioneered by the French military surgeon Robert Aubaniac, who described the technique in The technique described by Aubaniac involved a medial access, guiding the puncture laterally and inferiorly in the direction of the fossa adjacent to the sternum.
Postmortem dissections showed that the point at which the catheters entered the subclavian vein was close to the junction with the internal jugular vein. In , Seldinger 11 described intravascular insertion of catheters, advancing them along a flexible guidewire introduced by puncture.
This technique remains the basis for procedures used for endovascular access today. Insertion of central catheters via peripheral veins in the limbs was described in by Wilson, with the objective of monitoring the central venous pressure of critical patients. Percutaneous supraclavicular access to the subclavian vein was described in by Yoffa.
Evolution to long-term access routes began in , when Broviac created a silicone catheter that exited via the anterior wall of the thorax after subcutaneous tunneling from the puncture site. The device was synthesized in silicone and included a polyester cuff that provoked an inflammatory reaction, offering better fixation of the catheter by adhesion of the cuff to subcutaneous tissue. Another major step in the evolution of vascular accesses was the creation of totally implantable catheters.
This technique emerged during the s, after Belin et al. In , Niederhuber et al. Such totally implantable catheters are widely used today, primarily for cancer treatment, and are the subject of this article.
Different types of venous access can be classified in terms of duration of use, frequency of use, and the site at which the tip is positioned Table 1. Short-duration peripheral catheters are manufactured from teflon or silicone, are around 35 to 52 mm long, and are inserted via puncture of peripheral veins, in a low-risk procedure. They are inexpensive, offer short durability, and are most often used in clinical practice with hospitalized patients.
Short-duration central venous catheters are polyurethane devices of 20 to 30 cm in length and with calibers of up to 8 Fr, that are implanted via puncture of a central vein internal jugular, subclavian, axillary, or femoral , with the tip positioned close to the cavoatrial junction.
There are versions with single or multiple lumens, and they are always for continuous use, exclusively in patients who have been admitted to hospital.
The largest-caliber model 12 Fr , known as the Shilley catheter, offers the high flow rates needed for hemodialysis sessions or apheresis, with the drawback that they are short-duration. Peripherally inserted central catheters PICCs are also inserted by puncture of a superficial vein, generally in an upper limb antecubital, basilic, cephalic , or guided by ultrasonography US , also by puncture of the brachial vein.
These catheters are not tunneled, but they offer long duration and the tip is maintained in a central position. They can be used continuously or intermittently, for treatment at home or in hospital settings. The insertion procedure is low-risk and can be performed at the bedside, foregoing the convenience of controlling advancement of the catheter with imaging. Since these catheters are long 50 to 65 cm in length and of fine caliber up to 5 Fr , they are not appropriate for infusion of large volumes in short periods of time.
They offer the advantage of ease of removal, but there are disadvantages related to issues of esthetics and comfort. Tunneled catheters offer greater durability, because the subcutaneous path is a protective factor against infections, 18 in addition to providing better fixation for the device.
This cuff provokes an inflammatory reaction, leading to adherence, resulting in better fixation of the device around 1 month after implantation. Another type of long-stay catheter is the totally implantable version, known as a portacath.
These catheters have a diameter less than 10 Fr and can be implanted via a peripheral or central vein and, after taking a subcutaneous path, are connected to a reservoir port that is generally implanted over the muscular fascia of the site chosen for construction of the pocket that will accommodate the port. No part of the assembly is outside of the body and so this type of catheter has a lower risk of infection and greater durability than the semi-implantable type.
Devices are available with and without valves and in some valved models the valve is positioned in the port and in others it is at the catheter tip Figure 1. The theoretical advantage of valved catheters is to reduce the occurrence of malfunction caused by intracatheter thrombi, by preventing inadvertent reflux of blood.
However, the superiority of valved catheters has not been confirmed. Long-term catheters PICC, semi-implantable and totally implantable are manufactured from silicone or polyurethane, and each has different characteristics. While silicone offers better biocompatibility and lower risk of provoking thrombosis, 22 a polyurethane catheter has thinner walls, allowing a larger diameter internal lumen in relation to a silicone catheter with the same external diameter, resulting in a lower risk of obstruction.
Peripheral accesses are preferred for short-term infusion of solutions a few days in patients with a preserved venous network and for infusion of solutions that are not vesicant. If vesicant solutions leak, they cause intense irritation, formation of boils vesicles and tissue necrosis. Patients being treated with non-vesicant chemotherapy for shorter periods can benefit from this type of access.
Short-term central venous access should only be used with inpatients and for periods of less than 3 weeks. Nowadays, PICCs are increasingly fitted for patients on outpatient chemotherapy, because they allow intermittent use. Since part of the catheter remains outside of the body, exiting via the puncture site, they can cause discomfort.
High flow semi-implantable catheters permcath are indicated for patients who require hemodialysis for longer periods and for individuals on apheresis programs, which consists of a process for collecting peripheral stem cells mobilized into the blood circulation after treatment with granulocyte colony stimulating factor G-CSF , preparatory to bone marrow transplantation.
Hickman catheters offer the possibility of simultaneous infusion of different solutions, including blood products, in addition to their use for BMT. They also enable blood samples to be drawn for analysis, thereby offering increased comfort by avoiding frequent vein punctures, and can also be used for administration of prolonged intravenous parenteral nutrition.
The main indications for totally implantable catheters are a need for frequent venous access, use of vesicant drugs, and a peripheral venous system that cannot be used for access. These catheters require percutaneous puncture to access the port, which is why they are more indicated for intermittent use, allowing the skin to recover during intervals in treatment.
They are almost exclusively used for chemotherapy treatment of cancer patients. In general, this infrastructure is found in operating theaters and radiology suites. Generally, local anesthesia combined with sedation is sufficient. Since this is a clean operation, antibiotic prophylaxis is not required.
Choice of the implantation site is based on which vein will be used to insert the catheter and the site in which the port pocket will be created. The preference is for insertion into veins that drain to the superior vena cava system.
An anterior chest wall that does not offer adequate conditions is a relative indication for choosing veins of the inferior vena cava system, since the port can be placed in a number of alternative sites, such as the upper limbs.
The access technique is dependent of the vessel chosen. In general, superficial veins external jugular, cephalic, basilic, and saphenous are accessed by dissection, whereas deep veins internal jugular, subclavian, and femoral are reached by puncture 26 , 32 Figure 2. Refinements in materials needles, guidewires have resulted in puncture of deep veins becoming the procedure of choice in the majority of centers.
Utilization of ultrasonography in the operating room makes it possible to assess the vein chosen for puncture, allowing diagnosis of asymptomatic thrombosis before the operation is started. This resource also enables puncture to be guided by ultrasound, reducing the risk of accidents, such as arterial puncture and pneumothorax Figure 3.
When the option chosen is dissection of a superficial vein, a venotomy is performed to allow the catheter to be inserted and advanced until the tip reaches the central position.
The vessel is ligated distally and a proximal ligature is placed around the catheter, taking care not to constrict it. In the case of larger caliber veins, a suture around the incision, rather than ligature, allows maintenance of blood flow, avoiding thrombophlebitis Figure 4.
The venous path to the atrium is straighter on the right, which is why this side is preferred for insertion. The proximal extremity of the catheter is placed at the cavoatrial junction, carefully monitoring for possible arrhythmia provoked by the device. In many cases, the tip of the catheter may enter the right atrium, without harming the patient. The port pocket should be created in site that is firm and is distant from areas in which the skin has lost integrity, such as result from stoma, radiodermatits, or ulcerous tumoral lesions.
Whenever possible, the port is implanted in the anterior thorax wall, just above the fascia of the pectoral muscle Figure 5. In obese patients, very deep subcutaneous tissue could cause difficulties with puncturing the port, if it were placed directly against the muscle fascia. In such cases, the port pocket can be created more superficially, within the adipose plane, leaving subcutaneous tissue a minimum of 2 cm deep over the device.
When access is achieved via the internal saphenous or femoral veins, the port pocket can be constructed in the abdomen, medial of the anterior superior iliac crest, or on the anterolateral surface of the thigh Figure 5. After the port pocket has been correctly prepared, using rigorous hemostasis to reduce the risks of infection, the catheter is advanced along its subcutaneous path from the vein insertion site to the port pocket.
The port is then connected to the catheter and positioned in the pocket, where it is fixed with two non-absorbable sutures to the muscle fascia.
Intercurrent conditions caused by the operation to implant the device are related to accidents that occur during puncture to access a central vein, such as pneumothorax, hemothorax, and inadvertent arterial puncture, or to navigation of endovascular devices guidewire, introducer, catheter , which include venous drilling and myocardial injury. Hematoma and early infections at the pocket or along the catheter path are also adverse events that can be associated with the operation to place totally implantable catheters.
At our service, in a total of 1, procedures to implant totally implantable catheters, there were 18 1. Infectious complications are most frequently related with long-term catheters and are the principal cause for early removal before the end of the treatment of the catheter.
Diagnosis is by clinical examination when there are phlogistic signs pain, hyperemia, increased local temperature in the area of the port. There may be pus build up in the pocket, sometimes accompanied by dehiscence with drainage of purulent secretions.
Conservative treatment does not generally achieve good results, and in the majority of cases the catheter has to be removed and systemic antibiotic therapy given.
Diagnosis of bloodstream infections BSI in patients with long-term catheters is still a serious challenge. Fever and shivering are generally associated with BSI, but these are nonspecific symptoms. When a BSI is suspected, paired blood cultures BC should be conducted aerobic and anaerobic of samples from the central catheter and from the peripheral vascular access.
A diagnosis of BSI is confirmed in the following situations:. Time difference before positive result : central BC grows a microorganism at least 2 hours before the peripheral BC. While waiting for the BC results, empirical treatment should cover both Gram-positive and Gram-negative agents.
After identification of the infectious agent, treatment should be adjusted to match the culture results, 41 maintaining systemic antibiotics, combined with lock therapy for 7 to 14 days. After 72 hours of effective antibiotic treatment combined with lock therapy, a repeat pair of BCs should be conducted on samples collected via the catheter, irrespective of the clinical response observed.
If there are still positive results for the same infectious agent, then the catheter should be removed. Patients with bacteremia or fungemia that persists for 72 hours after removal of the catheter should be given antibiotic therapy for 4 to 6 weeks. Table 2 lists situations that demand immediate removal of the catheter, with no attempt to save it.
Lavado del catéter venoso central
Puertos para catéteres venosos centrales
Cateteres venosos totalmente implantáveis: histórico, técnica de implante e complicações