10 General Aspects of Head and Neck Brachytherapy

General Aspects of Head and Neck Brachytherapy

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THE GEC ESTROHANDBOOKOF BRACHYTHERAPY | Part II Clinical Practice Version 1 - 30/01/2019

position, the old days loops technique being a potential cause of kinking. After an HDR fraction, the catheters should be closed with dummy wires or nylon tubes after disconnection. This would not only avoid catheter kinking, but also ensure the cleanliness of the catheters. Potential displacement or kinking of the catheters has to be checked on a regular basis. This can be caused by the leaded protection device which can be modified by the prosthetist accordingly. Another cause is represented by post-implantation edema that may happen several hours after the implant and may require specific medication: steroids or anti-inflammatory treatment. In case of significant catheter displacement re-planning has to be considered. Before the first fraction takes place it is advisable to checkmanually the clearance of the catheter paths using a dummy wire. Too narrow catheter diameters or kinks can be detected in this way. This maneuver also allows checking the resistance to the passage of the source of each individual catheter. Resistance can be anticipated by the position and curvature of the catheters in the 3D image reconstruction. Sometimes it is necessary to implant catheters in a loop technique. If the loop diameter is close to the minimum allowed diameter of the afterloading unit for such techniques as described in the afterloader specification, care should be takenwhen treating with these tubes. Another alternative is to use one of the different non-looping techniques described in the literature [12]. If a leaded shielding is planned, this needs to be placed comfortably before the treatment making sure that this does not displace any of the catheters and does not represent any choking hazard in case of displacement. Connection and disconnection of the catheters to the transfer tubes must be done with care to avoid displacements of the implanted catheters. When a patient is disconnected after a treatment fraction, the implant tubes should be closed with metal dummies or nylon wires.This is to prevent kinking of the catheters and to keep the inner part of the catheters clean. 11.3. Medication and Nutrition Mouthwashes, usually a combination of antibiotics, antifungals and anti-inflammatory drugs are systematically prescribed. In patients who cannot rinse, an auxiliary suction device is helpful to maintain an adequate hygiene of the implanted area. Adapted analgesia has to be systematically offered to the patient with follow-up of potential secondary effects. Antibiotics can be necessary, depending on the tumor site and the risk of infection. Liquid or pureed diet can be possible in certain patients and in certain disease sites, however, some cases will require a nasogastric tube or percutaneous gastrostomy to avoid pain as well as to ensure proper nutrition and hygiene. If a nasogastric tube is anticipated, this should be placed during the general anesthesia required for the implant.

patient with air obstruction or a bleeding of the puncture zone. A severe bleeding inside the posterior oral cavity and oropharynx is not easy to manage and the radiation oncologist must always be aware of this possibility. An intravenous access is recommended as well as the presence of a nurse and/or an assistant close to the doctor. Aspiration, good light and clear vision of the buttons and oral cavity, with some device to keep themouth open aremandatory. The patient has to avoid eating and drinking at least 6 hours before catheter removal. The removal is usually done without general anaesthesia, under a soft sedation if necessary. Local anaesthesia with lidocaine spray in the oropharynx reduces the vomiting reflex. In cases of base of tongue, where the buttons can be situated deep and bleeding can be difficult to stop, a general anaesthesia should be considered to prevent complications. 12.2 Technique Disinfection of the skin is made before the removal of the tubes. Skin is easier to clean than the oral cavity. A previous mouthwash with diluted clorhexidine is useful. The tubes are usually removed one by one. The first button is identified and clamped with a small forceps. The tip of the finger is placed next to the button, and the aspirator in the posterior part. It is better to cut the external part of the tube on the skin, so the whole length of the tube cannot bring detritus into the mouth. With the forceps the tube is removed through the openmouth and press with the finger at the puncture site, without waiting for seeing if bleeding appears. A third person looks at the skin puncture, and if no bleeding happens, we move apart the finger slowly looking at the tongue and with the aspirator. If there is some bleeding, bimanual compression of the inner and outer puncture areas, tongue and skin, during a few minutes, is usually sufficient to stop it. The same action is repeated with every catheter. We wait for a while and finish with a simple dressing of the small holes on the skin. 12.3 Discharge orders A verification of the absence of bleeding and/or infection is mandatory before the patient returns back home. The patient must also be instructed about the inflammatory reaction, which occurs after the removal of the implants, and starts at about 7 days, increases until the third week, is stable for one week, and then decreases and finally disappears at the end of the sixth week. These reactions can be particularly severe in diabetic and/or high blood pressure patients. Specific dietetic recommendations with dietary supplements can be prescribed. Oral antiseptics are recommended during this time. If the patient has received antibiotics during the treatment, it is good tomaintain it for 2-3 more days. Anti-inflammatories or analgesics can be offered if required.

13. FOLLOW-UP

12. IMPLANT REMOVAL

13.1. Schedule Patients should be regularly followed-up by the radiation oncologist four to six weeks after treatment, to evaluate the efficacy of the treatment as well as acute local effects. Follow-up visits can be planned every three months during the first two-three years to

12.1. Safety concerns The removal of interstitial tubes is done in an operating theatre with Oxygen supply and the possibility tomanage a reaction of the