Radiology care post-trachestomy:
( Portable chest radiograph)
Among critically ill patients, tracheostomy is one of the oldest and most commonly performed surgical procedures. Tracheostomy creates an artificial opening, or stoma, in the trachea to establish an airway through the neck (Ron B,et al,(2012). The stoma is usually maintained by inserting a tracheostomy tube through the opening. Tracheostomy is performed on the intensive care units (ICUs) for upper airway obstruction, prolonged endotracheal intubation, and for those requiring bronchial hygiene. After the each surgery the patent need very careful care. Within the ICU the radiology care performing chest radiography (CR) immediately after tracheostomy tube placement (post-tracheostomy), by using of mobile radiography machine, that to evaluate for early detection unsuspected complications and improper instrumentation placement.
The Equipment and Radiation exposure
The patient in the ICU ward usually critical ill and supported by mechanical monitoring devices the position these devices an important component of critical care managements is best checked radiographically. Chest radiograph should obtained immediately after trachestomy to check tube position and to search for any possible complication such as pneumothorax, pneumomediastinum or pleural effusion. Mobile Radiography is using radiographic equipment which easy to transported allow imaging services to be brought to patient,( kari.J wetterlin,(2016). There are two types of mobile machines, battery operated and capacitor discharge (Power source). The main mobile radiography components are generator, tube, tube stand, high tension transformer, control unit, and wheeled base,(Dr.Frank, E.D.Long,B.W.and Smith, B.J.(2007). Mobile machine have direct flat panel detector where it connect the machine by a tethered cord or communicates wireless technology, the image will appear immediately in the mobile machine.
Mobile machine is not better than stationary machine which is in the radiology department but it able to image most body parts and they differ in exposure factor and power sources. The range of total power in the mobile unit is from 15 to 25 Kiowatts while in the stationary radiography unit reach 150 kilwatts. The range of milliampere-second (mAs) typically from 0.04 to 320, while the kilovolt (peak) (kVp) from 40 to 130, (kari.J wetterlin,(2016). The other equipment which may use post –trachestomy is computed tomography. CT-scan are require since chest radiograph are often difficult to detect the injury of the adjacent structures which one of the complication of trachestomy placement , ( Spencer.B el.al, (2013).
The accuracy and efficacy of portable chest radiography depend on the optimal radiographic technique and availability of images to evaluated and rapid reporting by the radiologist. Three main technique consideration in the mobile radiography are grid, anode heel effect, and Source image distance (SID). The grid must placed in the correct and centered to central ray to avoid grid cutoff and image density is lost so, post-trachestomy portable chest radiograph it must be centered to approximately 7cm below jugular notch of the sternum . The heel effect cause decrease of image density under the anode side of mobile x.ray tube. Short SID and large field size are common in the mobile x.ray, therefore correct placement of the anode cathode axis with regard to anatomy is essential. The third technique consideration is the SID which should be maintanines at a 100 cm but sometime the distance is increased which leads the mA to be increased and the portable machine has a limit means it gives a longer exposure which could causes motation artifact.
The good quality of chest radiograph depend on four main factor which are rotation, position, inspiration, and exposure. The patient and x.ray beam must be at right angle, any degree of deviation from the perpendicular will result in a rotated film. Post-trachestomy patient usually unconscious, difficult to give them the inspiratory instruction , so the radiographer should assess the patient chest wall when it become full with air, radiographer will expose.
Role of the radiographer and patient care
Radiographer should aware about the preparation for mobile examination. Pre examination preparation are first calling ICU ward to make sure patient is ready for x-ray and Getting full details of patient before going. Mobile machine should be ready and if battery operated machine is used making sure it is charge. Once arriving in ICU ward the radiographer should ask the nurse to check you have right patient to be x-ray. Set mobile in right position and exposure. One of the radiographer responsibility is to ask family members, visitors, staff there to wait outside the room as radiation protection for them. While the preparation during examination include explanation the procedure and communicate with patient if conscious, position the patient semi-erect but if cannot position patient supine Then put the cassette and tube in correct position. Also the radiographer should ask nurse for help if needed, explain breathing instruction if patient conscious and observe patient while exposing. The radiographer preparation after examination are taking detector and tube away from the patient, to keep patient in comfortable position radiographer should ask nurses for help. At the end, the radiographer must clean detector and mobile machine and keep it in proper parking position. Furthermore the very important role of the radiographer on the mobile radiography to keep himself, patient, staff and relative safe. The radiographer should stand away from radiations while exposing, proximately 2 meters and should stand at right angle to the primary beam and chest radiography. Patient must apply for him/her radiation protection such as gonad protection. While relative and staff must inform them to leave the room until exposing.
67year old male patient present to the AFH on 16/02/2018. Patient is on the bed, he is unresponsive, breathless, intubated and connected to mechanical ventilators. On 22.02.2018 portable chest radiograph is done pre-tracheostomy operation in the ICU ward. And on 26.02.2018 portable chest radiograph is done post-tracheostomy operation to be reviewed. On 01.03.2018 CXR is done to check the patient condition.
Cramberry.net. (2018). Physics – Chapter 29 (Merrill’s) – Mobile Radiography // Cramberry: Create ; study flash cards online. online Available at: https://cramberry.net/sets/29841-physics-chapter-29-merrills-mobile-radiograph Accessed 15 May 2018.
Kari.j wetterlin,(2016). MOBILE RADIOGRAPHY. online Radiology Key. Available at: https://radiologykey.com/mobile-radiography/ Accessed 11 May 2018.
Frank, E.D.Long,B.W.and Smith, B.J.(2007)Merrill’s Atlas of Radiographic Positions and Radiologic Procedures.V3, 11th ED.
Spencer.B el.al, (2013) Med-ed.virginia.edu. Chest Radiology. online Available at: https://www.med-ed.virginia.edu/courses/rad/cxr/technique3chest.html Accessed 11 May 2018.