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Content Reviewed 09/30/2008



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Sonography


A successful sonographic scan depends on getting the transducer into an accurate position on the patient and being able to maintain that position for an appropriate period of time. Being able to accomplish this while protecting the sonographer depends on appropriate placement of the patient in relation to the sonographer. This placement can be highly variable depending on:

  • The procedure being performed.
  • The size of the patient and the sonographer.
  • The type, size and placement of the equipment used.
  • The size and layout of the exam room.

Songraphers must be diligent in positioning all equipment such as exam tables, chairs, lights, and carts to ensure the best possible ultrasound scan while minimizing risk to the patient and themselves. This section deals with positioning the patient and arranging the equipment within the exam room to minimize awkward postures.


Body Posture Concepts
 

No matter what equipment you use or building you work in, keeping basic safe work practices in mind can help you work more safely when performing a scan. All the work items that you use in your scanning techniques should be adjusted as much as possible to ensure proper body positioning.


Potential Hazard

  • Tipping the head back or forward places stress on the neck and shoulders.
     
  • Reaching that involves pulling the elbow away from the body can stress the shoulder and back.
     
  • Bending and twisting the torso places stress on the low back.
     
  • Bending and twisting the lower arm and wrist places stress on the hand and elbow.
     
  • Prolonged standing, sitting or holding the arm or neck in a static posture can fatigue the shoulder, leg, neck or hand, as well as create a contact stress on various body parts such as feet, buttocks and the legs.

Possible Solutions

Place the patient and equipment in a position to allow the sonographer to work, as much as possible, in neutral postures that include straight wrist, bent less than 15 degrees, back straight, elbow close to the body, and head balanced. The following can help maintain these postures:

  • Reposition the patient and equipment to allow the sonographer to alternate between right and left hand scanning. This provides periods of rest for the hand/arm not used during the scan.
     
  • The patient is close to the sonographer minimizing reach. The chair is higher and the sonographer's eyes are level with the top of the monitor.
    Figure 1. The patient is close to the sonographer, minimizing reach. The chair is higher and the sonographer's eyes are level with the top of the monitor.
  • Keeping the body part to be scanned directly in front of the sonographer. (Figure 1)
    • Instruct patients to orient themselves to assist the sonographer in using neutral postures while performing scans. For instance, while performing scans on the side of a patient, have them roll onto their side.
    • Instruct patients to move as close to the sonographer as possible during scans.
    • Move to the other side of the table rather than reaching over the patient.
    • Scan carotid arteries or thyroid glands from the head of the patient rather than reaching from the side.
    • Avoid working behind the mid-line of the body, especially when performing transvaginal exams. Move to the feet for better access.
  • Keeping the head balanced and looking essentially straight ahead. Do not turn head to the side or look up or down.
     
  • Keeping shoulders relaxed. Do not hunch or raise the shoulders up during the procedure.
     
  • Keeping the torso straight. Do not bend.
     
  • Keeping the elbow bent at about 90 to 110 degrees and close to the body. Do not reach out and away from the body. The elbow should not be farther from the torso than about 30 degrees.
     
  • Keeping the wrist straight, not flexed, extended or deviated to either side.
     
  • Minimizing sustained bending and twisting and exertions such as reaching and lifting.
    A natural reach zone where the most frequently accessed controls are easily accessed in the sitting or standing position, using the left or right hand.
    Figure 2. A natural reach zone where the most frequently accessed controls are easily accessed in the sitting or standing position, using the left or right hand.
  • Alternating between sitting and standing positions.
     
  • When sitting, ensure that feet and back and buttocks are supported.
     
  • Work in a standing position when performing procedures that require significant force or when working with bariatric patients. When standing:
    • Keeping both feet on the ground and weight evenly distributed.
    • Use anti-fatigue mat or cushioned insoles when standing on hard floors for prolonged periods of time.
  • After standing, work in a seated or sit/stand position which provides periods of rest for the feet, legs and back.
     
  • Grip the transducer with the whole hand as much as possible. Minimize using only the fingers to grip the handle. Take mini or working rest breaks.
     
  • Periodically look away and focus at a different distance for a few seconds to allow the eye muscles a period of rest and recuperation.
     


Positioning and Adjusting the Exam Table

The position of the table within the exam room is critical as is the table's design and adaptability. It should be positioned in an area where there is access to all sides of the patient, as well as to the other tools and devices needed for the scan. It should be adjustable a vertical height where it is convenient for a variety of sizes of sonographers. Drop-down sections or cutouts should be incorporated and used whenever appropriate to minimize stressful postures.


Potential Hazard

The table is too high, the chair too low, and the patient too far away.
Figure 3. The table is too high, the chair too low, and the patient too far away causing the sonographer to lean and reach.
  • Lack of adequate height adjustability for exam tables may cause the sonographer to:
    • Lean, twist and bend at the waist if the sonographer is too tall for the table height.
    • Tilt the head forward or to the side if table is too low.
    • Elevate and abduct (spread) the arm if table is too high. (Figure 3)
    • Use elevated arms to reach up and over patients.
  • Use of awkward postures such as extended and elevated reaches or bent wrists when accessing areas of the patient. This is especially the case if repositioning is limited by the exam bed being positioned close to obstructions such as walls or incompatibility of the chair and table.

Possible Solutions

  • Examination tables should be height-adjustable to minimize extended reaches, elevated arms and wrist deviation. The examination table should:
    • Elevate to allow taller sonographers or those that prefer to stand while performing procedures without bending at the waist.
    • Lower to allow shorter sonographers or those who prefer to sit while performing procedures without lifting the arm to reach up and over patients.
    • Elevate or lower so most scans can be performed with a minimum of bending of the wrist.
    • Lower so that patients can get onto the table with minimal effort and allow the sonographer to raise the table to perform the scanning task.
A removable or droppable footboard provides better access and allows the sonographer to avoid shoulder injury by keeping their arm by their side.
Figure 4. A removable or droppable footboard provides better access and allows the sonographer to avoid shoulder injury by keeping their arm by their side.
  • Examination tables should provide adequate access for a number of procedures and patient applications.
    • Cutouts on the side can provide improved access to the apical (heart) region for cardiac imaging.
    • Stirrups and removable dropped footboards provide improved access when performing certain gynecological procedures.
      (Figure 4)
  • Provide height-adjustable equipment (e.g., monitors, keyboards and beds) so sonographers can frequently change from a seated posture to a standing posture while still maintaining neutral body postures.
  • Ensure open access from all sides of tables and consoles to provide sonographers with sufficient space for the sonographer's legs. This allows the sonographer to get close enough to minimize extended reaches.
     
  • Be aware of and use ergonomic principles when moving heavy items such as exam tables or consoles.
    • Unlock wheels before attempting to move items.
    • Push rather than pull unless the item moves easily.
    • Try to push with the hands at about chest height.
    • Enlist the assistance of others if the object is difficult to move.


Positioning Seating

Since scans may be time-consuming, it is often appropriate to provide some kind of seating to allow the sonographer to have periods of rest and recuperation. If provided, the chair must be height-adjustable and movable to interface appropriately with the exam table and the ultrasound console. It must also accommodate a variety of sonographers and procedures.


Potential Hazard

Cardiac scanning without a height adjustable table and chair forces the sonographer to lift the arms away from the body.
Figure 5. Cardiac scanning without a height-adjustable table and chair forces the sonographer to lift the arms away from the body.
  • Sonographers may be required to perform extended reaches, elevated arms and possibly need to reach behind the plane of the torso (Figure 5) if:
    • Seating is positioned below the exam table or other items used during the scan.
    • Seating is improperly positioned in relation to the exam table or other items used during the scan.
    • There is inadequate room under the exam table due to obstructions that force the sonographer to sit away from the table.
  • Sonographers may experience contact stress to the back of the legs or wrists and forearms if:
    • Seating is positioned below the exam table or console so that the forearm rests on a hard or sharp work surface.
    • There is inadequate support for the feet when chairs are elevated.
  • Sonographers may work with a bent wrist if the seating is too high or low in relation to the patient or the console.

Possible Solutions

  • Provide height-adjustable chairs and exam tables so the height of the sonographer can be adjusted in relation to the patient and ultrasound equipment. The height should be adjustable so the sonographer can:
    • Keep the elbows close to the torso and the forearm approximately parallel with the floor. Reaching up to 20 inches can fatigue the arms in as little as 7 minutes. [Handbook of Human Factors and Ergonomics, 1997]
    • Keep the back straight and supported by the backrest of the chair.
    • Keep the wrist straight and inline with the forearm.
The knees are lower than the hips and the correct upright position is maintained. The back and torso hare supported for a variety of procedures. The knees are lower than the hips and the correct upright position is maintained. The back and torso hare supported for a variety of procedures.
Figure 6. Figure 7.
The knees are lower than the hips and the correct upright position is maintained. The back and torso are supported for a variety of procedures.
  • Provide seating with support for the buttocks, feet and torso (Figures 6 and 7).
    • Seating should have an adjustable foot ring if the sonographer's feet do not reach the floor.
    • Seating should have a height-adjustable backrest to support the back.
    • Seat pan should be padded and large enough to support the buttocks and thighs.
  • The configuration of the seating should be compatible with the other items in the exam room, such as tables and consoles.
    • Seating should generally not have armrests since these limit access to the patient and interfere with other items in the exam room.
  • A sit/stand seat or a chair with a saddle type configuration allows the knees to be lower than the hips. This can be beneficial in situations where there is restricted space under the table or console.
     
  • Provide height-adjustable equipment so that sonographers can frequently change from a seated posture to a standing posture while still maintaining neutral body postures.
A removable or droppable footboard provides better access and allows the sonographer to avoid shoulder injury by keeping their arm by their side.
Figure 8. A removable or droppable footboard provides better access and allows the sonographer to avoid shoulder injury by keeping their arm by their side.
  • Provide adequate space and maneuverability for placement of the chair, exam table and console so the sonographer can perform scans while maintaining neutral postures. (Figure 8)
     
  • Ensure open access from all sides of tables and ultrasound equipment to provide sufficient space for the sonographer's legs. This will allow the sonographer to get close enough to the patient to minimize extended reaches.
  • Reposition the seating as needed throughout the exam to minimize reaching. The chair may be the primary item for rearrangement, since the chair is probably easier to move than the console or exam table.
     
  • Provide a swivel seat on the exam chair so that the sonographer can easily turn from the ultrasound equipment to the exam table. This will allow the sonographer to keep the work directly in front of the body and minimize extended reaches and reaches behind the plane of the body.
     
  • Seating should have casters for ease of arrangement around the exam table but the casters should be lockable to prevent the chair from rolling backward.
     
  • Work from a seated posture to provide periods of rest for the feet and legs. Be aware that a standing posture is often better when performing tasks that require significant force or large range of motion.
     
  • Note: Use of insoles rather than fatigue matting may be preferable since fatigue matting can make moving items around the exam room difficult.


Positioning the Ultrasound Equipment

The keyboard and the monitor are the principle interface points between the sonographer and the ultrasound equipment. This section deals primarily with the keypad, toggle, thumbwheels or devices typically found on the keyboard. See Positioning the Monitor for information on the monitor.


Potential Hazard

  • Repeated reaching to the keyboard while performing ultrasound exams can stress the upper arm and shoulder.
     
  • Repeated toggling and keystrokes with the wrist in a extended posture can stress the wrist and hand.

Possible Solutions

User can maintain the arm close to the torso, while scanning and operating the console. The monitor can be viewed without tilting the head. Postures are maintained and the feet are firmly supported.
Figure 9. Sonographer can maintain the arm close to the torso while scanning and operating the console. The monitor can be viewed without tilting the head. Postures are maintained and the feet are firmly supported.
  • Provide adjustable chairs and exam tables so the posture of the sonographer can be properly adjusted in relation to the patient and ultrasound equipment (Figure 9). Adjustments should allow the sonographer to:
    • Keep the elbows close to the torso and the forearm approximately parallel with the floor by adjusting the height of the keyboard.
    • Keep the back straight and supported by the backrest of the chair by allowing the ultrasound equipment to be properly positioned horizontally and vertically in relation to the sonographer.
    • Allow the neck to balance comfortably on shoulders without twisting, leaning forward, tilting back or bending to the side. Position the keyboard in relation to the monitor.
    • Keep the wrist straight and inline with the forearm by raising, lowering or tilting the keyboard for both sitting and standing operations.
  • Place the ultrasound equipment as close to the exam table as possible to minimize the awkward postures, such as reaching and turning of the head, that must be used while performing the exam. Ideally, sonographers should be able to access all equipment and materials while keeping the elbows close to the body.
     
  • Position the ultrasound equipment as close to the sonographer as possible. The equipment should either be pulled closer to the sonographer or the sonographer should move the seating closer to the console.
     
  • The ultrasound equipment should be easily movable to allow for frequent changes between right- and left-handed scanning.
     
  • The keyboard should move independently of the monitor.
     
  • Be aware of and use ergonomic principles when moving heavy items such as exam tables or ultrasound equipment.
    • Unlock wheels before attempting to move items.
    • Push rather than pull.
    • Try to push with the hands at about chest height.
    • Enlist the assistance of others if the object is difficult to move.

 

Positioning the Monitor

The monitor is a critical part of the exam ultrasound equipment. Sonographers must view the monitor while operating the transducer to ensure that they are obtaining the proper visual scan. Older ultrasound equipment often provides little adjustment possibility, especially for the monitor which is often attached directly to the console.


Potential Hazard

Equipment and monitor in a fixed height.
Figure 10. Equipment and monitor at a fixed height.
  • Repeated use of awkward postures due to inappropriately placed monitors.
    • Repeated or prolonged looking to the side to view monitors.
    • Repeated or prolonged tilting of the head up or down to view monitors that are too high or too low. This is especially a problem for bifocal sonographers. (Figure 10)
    • Leaning forward to view distance monitors or monitors with image that are unclear due to poor resolution or excessive ambient lighting.
  • Eye strain, blurred vision, double vision, dry eyes and headache resulting from prolonged concentration to view images that are unclear or washed out on the monitor.

Possible Solutions

This monitor is independently adjustable from the console allowing it to be ideally positioned.
Figure 11. This monitor is independently adjustable from the console, allowing it to be ideally positioned. 
  • Provide a fully adjustable monitor on a monitor arm which is detached from the main console (Figure 11). It should be easily positioned for both sitting and standing postures and for a variety of procedures. The following can help maintain a correct body posture:
    • The monitor should be placed directly in front of the sonographer to minimize looking to the side.
    • The top of the monitor should be at about eye height with the viewing area slightly below eye height.
    • The monitor may need to be adjusted downward for bifocal wearers.
    • The monitor should be about 18 to 30 inches in front of the sonographer.
    • Generally, flat screen monitors are lighter and easier to adjust to varying positions for a variety of procedures.
  • Have a monitor on each side of the bed. These should be easily repositionable. LCD or plasma monitors are preferable in high light areas.
     
  • Consider the following measures to reduce eye strain when using the ultrasound monitor:
    • Use a flat screen LED monitor that will provide better contrast and picture in high ambient light conditions.
    • Close blinds or dim lights to lower ambient lighting.
    • Adjust illumination, brightness and contrast to improve visual clarity.
    • Use single vision or custom eyewear that is appropriate for the viewing distances found in most ultrasound procedures.
    • If possible, look away from the monitor for short periods during extended procedures.
  • Do not share the monitor with patients if this compromises proper placement of the monitor for the sonographer. Provide an additional monitor for patients if they need to view the procedure.

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