Chapter 13. Assessment and monitoring
Clinical assessment
Colour
• Pallor: very pale appearance, best visualised in the conjunctivae or the mouth. Usually a sign of anaemia but may also be seen in vasoconstriction due to hypotension, hypothermia or severe pain
• Flushing or redness of the skin is caused by vasodilation and may be a sign of fever, extreme exertion or superficial burns
• Cyanosis refers to bluish-grey discolouration of skin or mucous membranes caused by an excess of deoxygenated haemoglobin:
Central cyanosis – imperfect oxygenation of the blood by the lungs or where deoxygenated blood bypasses the lungs for example in congenital heart defects.
Peripheral cyanosis – where slow blood flow leads to increased deoxygenation of the haemoglobin in the peripheries. May be a normal finding for example in patients who are cold.
Pulse
• In the collapsed patient, palpate for a pulse at the carotid or the femoral artery
• The brachial pulse is recommended for palpation in cardiac arrest in infants
• Consider the rate, strength and character of the pulse
• Heart rate can also be documented by the ECG or the pulse oximeter.
Respiratory rate
• Always measure the respiratory rate in breaths per minute
• Neonates have the highest normal respiratory rate and it falls progressively up to the adult range of 12–18 breaths/minute
• A rapid respiratory rate is known as tachypnoea. Rates >30 breaths/minute are usually a sign of serious illness
• Conscious patients may be using their accessory muscles of respiration, e.g. in severe asthma
• A low respiratory rate is bradypnoea, sometimes caused by opiate use
• Some patients with heart failure, neurological disease or drug intoxication demonstrate varying respiratory rate and depth known as Cheyne–Stokes respiration.
Blood pressure
• Accurate blood pressure measurement is important and allows successive readings to be compared to allow monitoring of the patient’s progress and response to treatment
• Most portable monitors now provide automatic blood pressure monitoring
• Anaeroid sphygmomanometers are used if electronic devices fail or are unavailable
• Where possible the patient should be seated comfortably, with the upper arm at the level of the heart
• The cuff must be correctly sized to the patient – small cuffs for children and large cuffs for the obese adult
• The ideal size of cuff is equal in width to approximately two-thirds of the length of the upper arm
• The blood pressure cuff is applied to the upper arm, in the absence of intervening clothing. Most modern cuffs have a method of indicating the correct position of the cuff over the brachial artery
• Portable monitors usually allow the interval between blood pressure measurements to be adjusted depending on the patient’s requirements
• Systematic errors are often seen when the pulse is irregular, such as in atrial fibrillation.
Intra-arterial blood pressure monitoring
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