Chapter 24: Clinical measurement

1. What skills are needed to complete a full set of clinical measurements?

Answer: The ability to look, listen and feel combined with knowledge of normal physiology.

2. Why would you vary your approach to taking clinical measurements in different fields of nursing?

Answer: The approach you take is dependent on the age, mental capacity and understanding of the patient you are assessing. The different fields of nursing also require different measurements dependent on the circumstances.

3. When would gloves and aprons be worn to take clinical measurements?

Answer: Apron and gloves should only be worn if undertaking clinical measurements that require the handling of body fluids such as blood and urine.

4. In a patient’s home which clinical measurements would you be able to undertake without any equipment?

Answer: The patient’s respiratory rate, heart rate and capillary refill time.

5. Why are respiratory rates significant indicators of a patient’s deteriorating physiological condition.

Answer: They can be altered by respiratory, cardiovascular and metabolic failure.

6. What else would you observe when taking a respiratory rate?

Answer: As you approach the patient, observe for signs of hypoxia (central cyanosis – a blue/purple tint, around the lips, earlobes, nose and upper chest), does the patient appear to be breathing fast or slow, are they making any noises when breathing in or out and do they look as though the breathing is labored? Whilst taking the respiratory rate note the depth of the respirations, are they deep or shallow? is the breathing pattern regular? does the chest rise and fall equally on both sides (symmetry)? is the patient using any accessory muscles, such as shoulder and abdominals?

7. Explain why a patient with a good pulsatile waveform on a pulse oximeter giving an accurate normal SpO2 recording may be acutely ill?

Answer: SpO2 reflects the peripheral arterial oxygen levels obtained by non-invasive pulse oximeters attached to patients’ peripheral areas. They do not provide evidence of a patient’s ability to expire carbon dioxide. Pulse oximeters can give false readings in the presence of carbon monoxide and meth haemoglobin as both of these bind to haemoglobin and the pulse oximeter is unable to distinguish which of these substance the haemoglobin molecules are carrying. 

8. Why do pulse rates need to be taken manually?

Answer: To provide rate, rhythm and quality as the rate can be inaccurate if the pulse rate is irregular or if the patient has poor peripheral circulation and the pulse is weak and difficult to detect.

9. What might be the cause of a weak, thready pulse?

Answer: The most common causes of a weak, thready pulse are poor peripheral circulation caused by shock, hypothermia or a cold environment.

10. A ______ blood pressure less than ______ or a drop of ______ from the patient’s normal systolic blood pressure indicates ______ which is a ______ requiring rapid treatment and a search for the cause.

Answer: systolic, 90 mmHg, 40 mmHg, hypotension, medical emergency

11. Why would you try to use the same ear for tympanic temperature measurements?

Answer: Anatomical differences can account for a 1°C difference.

12. If a patient is not catheterised how do you ensure that they are passing adequate volumes of urine?

Answer: If they are alert and orientated and you are not concerned about their fluid status ask the patient if they have recently passed urine and was it the same amount as normal. If you are concerned about the patients fluid status ask them to pass urine into a bedpan or urine bottle and measure the amount or weigh the receptacle on the ward scales and minus the weight of the receptacle. The amount measured is divided by the number of hours since it was last measured and then recorded on the fluid chart at the time measured.

13. Why would you never squeeze the finger when taking a blood glucose sample?

Answer: This may result in inaccurate results from interstitial fluid in the sample.

14. Why are early warning scoring systems used in hospitals and in some areas of pre hospital emergency care?

Answer: Physiological track and trigger scoring systems provide early recognition of potential or established acute illness, with the aim of initiating early intervention and clinical decision making. They are used as surveillance systems for all patients in hospitals, tracking their clinical condition, alerting the clinical team to any clinical deterioration and triggering a timely clinical response