Age Temperature Blood Pressure, Lower Limit (mm Hg)   Pulse (Heart) Rate, Upper Limit (beats/min) Respiratory Rate, Upper Limit (breaths/min) Weight (kg)
0–1 mo   60/40   180 60 3–4
2–12 mo   70/45   160 50 5–10
12–24 mo   75/50   140 40 10–12
2–6 y   80/55   120 30 13–25
6–12 y   90/60   110 20 25–40
>12 y   90/60   100 20 140–60

 

Temperature Heart Rate, Upper Limit (beats/min) Respiratory Rate, Upper Limit (breaths/min) Blood Pressure,* Lower Limit (mm Hg)
  180 60 60/40

 

  • Temperature
  • Pulse Rate
  • Respiratory Rate

    Temperature Heart Rate, Upper Limit (beats/min) Respiratory Rate, Upper Limit (breaths/min) Blood Pressure,* Lower Limit (mm Hg)
    Less than 38.5°C/101.3°F      

 

 

 

 

 

Always include BP and heart rate supine and after the patient has been standing 1 min if volume depletion (GI bleeding, pancreatitis, diarrhea, or vomiting) or autonomic insufficiency is suspected, especially if the patient reports dizziness or syncope.

The blood pressure is recorded as two readings:

1. Systolic pressure, which occurs during the maximal contraction of the heart

2. Diastolic or resting pressure.

Reference ranges for blood pressure
Stage Approximate age Systolic Diastolic
Range Typical example Range Typical example
Infants 1 to 12 months 75-100 85 50–70[17] 60
Toddlers 1 to 4 years 80-110 95 50–80[17] 65
Preschoolers 3 to 5 years 80-110[17] 95 50–80[17] 65
School age 6 to 13 years 85-120[17] 100 55–80[17] 65
Adolescents 13 to 18 years 95-140[17] 115 60–90[17] 75

 

 

Mean Arterial Pressure (MAP)

Calculated as DBP + [(SBP – DBP)/3]

 

 

Pulse Pressure (SBP – DBP)

The difference between the systolic and diastolic pressure is called the pulse pressure.

Wide Pulse Pressure:

(> 40 mm Hg) associated with:

  • Thyrotoxicosis
  • Arteriovenous fistula
  • Aortic insufficiency
Narrow Pulse Pressure:

(< 25 mm Hg) associated with:

  • Significant tachycardia
  • Early hypovolemic shock
  • Pericarditis
  • Pericardial effusion or tamponade
  • Ascites
  • Aortic stenosis
Paradoxical Pulse:

Systolic BP changes during the respiratory cycle as a function of changes in intrathoracic pressure (ee Chapter 13 for measurement technique)]. Normally, systolic BP falls 6–10 mm Hg with inspiration. If this variation occurs over a wider range (> 10 mm Hg), the patient is said to have a paradoxical pulse (Figure 20–1, below). Associated conditions include:

Image not available.

Paradoxical pulse.

  • Pericardial tamponade
  • Asthma and COPD
  • Ruptured diaphragm
  • Pneumothorax

Technique

The measurement of these pressures is now usually done with an aneroid or electronic sphygmomanometer.

The classic measurement device is a mercury sphygmomanometer, using a column of mercury measured off in millimeters.

In the United States and UK, the common form is millimeters of mercury, whilst elsewhere SI units of pressure are used.

There is no natural 'normal' value for blood pressure, but rather a range of values that on increasing are associated with increased risks. The guideline acceptable reading also takes into account other co-factors for disease. Therefore, elevated blood pressure (hypertension) is variously defined when the systolic number is persistently over 140–160 mmHg. Low blood pressure is hypotension. Blood pressures are also taken at other portions of the extremities. These pressures are called segmental blood pressures and are used to evaluate blockage or arterial occlusion in a limb (see Ankle brachial pressure index).

 

Hypertension is defined as a systolic blood pressure of ≥140 mm Hg or a diastolic blood pressure of ≥90 mm Hg measured on two occasions at least 6 hours apart.

Guidelines for measuring Blood Pressure1

• The patient should sit for several minutes in a quiet room before BP measurements are taken. Pain, stress, a full urinary bladder, a recent meal, and talking or active listening during measurement affect BP. Having smoked a cigarette within 15–20 minutes can elevate the BP by 5–20 mm Hg.
• Take at least 2 measurements spaced by 1–2 minutes and additional measurements if the first 2 are quite different.
• Using a bladder that is too narrow yields false high readings. Instead of the standard cuff (12–13 cm long, 35 cm wide) use an appropriate larger cuff in patients with increased arm circumference.
• Use phase I (first tapping sound) and V (disappearance) Korotkoff sounds to identify systolic and diastolic BP values, respectively.
• Do not deflate the cuff too rapidly, otherwise individual Korotkoff sounds are missed and too low a value is measured; start with a deflation rate of 2 mm/s.
• Measure the heart rate by palpation and watch out for arrhythmia, which mandates repeated BP measurements.
• At the first visit, measure BP in both arms and take the higher value as the reference; measure BP at 1 minute and 5 minutes after standing upright if the patient has a disorder that frequently causes orthostatic hypotension.

Between 50 and 80 beats per minute.

The pulse is commonly taken from the radial artery at the wrist.

Sometimes the pulse cannot be taken at the wrist and is taken at the elbow (brachial artery), at the neck against the carotid artery (carotid pulse), behind the knee (popliteal artery), or in the foot dorsalis pedis or posterior tibial arteries. The pulse rate can also be measured by listening directly to the heartbeat using a stethoscope.

Normal is 16–20 breaths/minute.

<