From the Research
The most effective method for assessing clubbing of the nails in clients with chronic respiratory conditions, such as hypoxia, is by using the Schamroth's window test, which involves placing the nail beds of each index finger together to determine the angle of the nail plate, as this technique allows for the evaluation of the angle between the nail plate and nail bed, and is supported by the most recent study 1. This technique is crucial in identifying clubbing, which is characterized by an increase in the angle between the nail plate and nail bed, typically beyond 180 degrees, resulting in a convex appearance. The Schamroth's window test is a simple yet effective method for assessing clubbing, as it allows the nurse practitioner to evaluate the angle between the nail plate and nail bed, and is supported by the most recent study 1.
Some key points to consider when assessing for clubbing include:
- The angle between the nail plate and nail bed, which should be less than 180 degrees in normal nails
- The presence of a diamond-shaped window between the nail bases when the dorsal surfaces of opposite fingers are placed together, which disappears in clubbing
- The increase in soft tissue at the nail base, which can be measured using radiographic evaluation, as demonstrated in a study 2
- The association between clubbing and chronic respiratory conditions, such as hypoxia, which can stimulate the release of growth factors and cause vascular changes in the nail beds, as discussed in a study 3
It is essential to note that while other assessment techniques, such as measuring the nail bed thickness or evaluating the digital index, may provide additional information, the Schamroth's window test is the most effective method for assessing clubbing, as it is supported by the most recent study 1 and is a simple yet effective technique for evaluating the angle between the nail plate and nail bed.
In clinical practice, the nurse practitioner should prioritize the Schamroth's window test when assessing for clubbing, as it is a reliable and effective method for identifying this condition, which can be an early indicator of serious cardiopulmonary disease requiring further investigation, as highlighted in a study 1.