Mr Potter is from the School of Exercise Science and Athletic Training, West Virginia Wesleyan College, Buckhannon, West Virginia; and Dr Sibold is from the Department of Rehabilitation and Movement Science, University of Vermont, Burlington, Vermont.
The authors have no financial or proprietary interest in the materials presented herein.
Address correspondence to Brian Potter, MS, ATC, EMT-B, School of Exercise Science and Athletic Training, West Virginia Wesleyan College, MSC 1796, 59 College Avenue, Buckhannon, WV 26201; e-mail: email@example.com.
Throughout the course of their education, athletic trainers are taught a number of skills related to clinical evaluation and testing, including the capture and interpretation of vital signs. Vital signs assessment is a core educational competency that is reinforced and mastered through practice in both the classroom and clinical settings. The mechanics of taking vital signs is not difficult; however, prudent interpretation of vital signs requires a great deal of training and practice. Vital signs are only a piece of the evaluation puzzle, and the ability to interpret the findings as part of the clinical decision paradigm is a skill that every athletic trainer needs. The purpose of this Pearls of Practice article is to review the basic vital signs, highlight the importance of vital signs trending, and discuss the concept of the “Rule of 100s.”
Assessment of Vital Signs
It is important to first review vital signs assessment. Heart rate (HR), blood pressure (BP), respirations, skin and body temperature assessment, and pupil assessment are considered the 5 basic vital signs. In many arenas, pulse oximetry is added to this list as a sixth vital sign.1–3 Standard techniques for vital signs assessment and accepted normal findings for vital signs are well documented in the literature (Table). However, an alternative technique of obtaining BP by palpation may not be as familiar or as commonly used. This technique involves inflating the BP cuff while simultaneously palpating the radial artery. The cuff is inflated approximately 40 mmHg beyond the point at which the radial pulse disappears, then the valve is released. The point at which the radial pulse returns is recorded as the systolic BP.2,4 Although a diastolic measure cannot be obtained using the palpation method, the systolic measure is still useful.
Table: Normal Vital Signs
Some clinicians may also be less familiar with pulse oximetry. Pulse oximetry provides a measure of the percentage of oxygen within the blood, obtained through use of an electronic finger sensor. Under normal conditions, the pulse oximetry reading will generally be between 96% and 100%, with patients exhibiting a reading of <90% usually requiring treatment.4 However, it is important to note, that the pulse oximetry reading obtained should be correlated closely with the patient’s signs and symptoms, and treatment should not be based on the oximetry reading alone.5
Vital Signs Trending and the Rule of 100s
The first set of vital signs obtained from a patient provides a baseline from which to compare subsequent sets of vital signs. This process of serial assessment is commonly known as “vital signs trending.”2 As described by emergency department physician Jim Kyle, MD (personal communication, March 1998), the Rule of 100s is a simple framework to provide guidance when trending vital signs for clinical decisions. The rule states that if, on initial assessment of vital signs, HR is >100 beats per minute (bpm), systolic BP is <100 mmHg, and/or body temperature is >100°F, vital signs trending should be initiated, repeating assessment every 10 minutes. If after 30 minutes of trending, the patient’s HR is still >100 bpm, systolic BP is still <100 mmHg, and/or body temperature is still >100°F, the athlete should be referred to the emergency department.2 It is important to note that the Rule of 100s should be used when signs or symptoms warranting immediate transport to a hospital emergency department have been ruled out, but the potential that the athlete’s condition might deteriorate remains.
Subtle trends in vital signs can be critical clues to a significant injury or illness in the athlete. Many variables can affect vital signs, such as medications, performance-enhancing substances, underlying clinical pathology, and the athletic activity itself. During exercise, elevations in HR, BP, and respirations are expected; however, after exercise has been discontinued, vital signs typically return to normal ranges in a relatively short period of time. Vital sign trending is important to document this return to accepted norms following exercise or to identify persistent abnormal findings, thus prompting referral of the athlete.
Consider the following example in further understanding vital signs trending: An athlete is evaluated for “feeling weak” immediately on leaving the field or court and exhibits a HR of 135 bpm on assessment of vital signs. Assuming no other findings in the initial examination warrant referral, vital signs trending would be initiated due to a HR >100 bpm and numerous potential medical causes of feeling weak. Under normal circumstances, over the course of the 30-minute period of vital signs trending, the athlete’s HR should return to a normal range of 60 to 100 bpm. After 30 minutes, if the HR remains >100 bpm, the athlete should be referred to the emergency department for further evaluation to determine the cause of the persistent tachycardia.
Although in this simulated case HR was the criteria for initiating vital signs trending, it is not difficult to imagine similar case scenarios where the same course of action would occur in response to persistent abnormalities in other vital signs.
Athletic trainers are the central component of the sports medicine team, ensuring that athletes experiencing injuries or acute illnesses receive appropriate evaluation, management, and referral as needed. It is not necessary for the athletic trainer to derive the precise diagnosis of an athlete’s condition; however, it is critical for the athletic trainer to be able to recognize the need for immediate referral to a hospital’s emergency department.
This article has discussed vital signs trending and the Rule of 100s as a method of determining the presence of underlying injury or illness in the athlete. It is important to note that the Rule of 100s is a set of guidelines based on the consensus of experts in the field and is not an evidence-based guideline. However, using these simple concepts can be a key component of sound, and in some cases, life-saving clinical decisions.
- Mistovich JJ, Krost WS, Limmer DD. Beyond the basics: interpreting vital signs. Emerg Med Serv. 2006;35(12):194–199.
- Rehberg RS. Sports Emergency Care: A Team Approach. Thorofare, NJ: SLACK Incorporated; 2007.
- Limmer DD, Mistovich JJ, Krost WS. Beyond the basics: putting the vital back in vital signs. EMS Mag. 2008;37(9):71–75.
- Pollack AN, ed. Emergency Care and Transportation of the Sick and Injured. 10th ed. Sudbury, MA: Jones & Bartlett; 2011.
- Greenwald I, O’Shea J. Measuring & interpreting vital signs: an in-depth discussion of the objective data points that lead to a presumptive diagnosis & treatment plan. JEMS. 2004;29(9):82–97.
Normal Vital Signs
|VITAL SIGN||NORMAL FINDING(S) FOR ADULTS|
|Heart rate||60 to 100 bpm|
|Blood pressure||90 to 140 mmHg systolic|
|60 to 90 mmHg diastolic|
|Respirations||12 to 20 per minute|
|Skin||Color: pink; temperature: warm; condition: dry|
|Body temperature||Approximately 98.6°F|
|Pupils||Equal, round, and reactive to light|
|Pulse oximetry||95% to 100%|