Vital sign normal ranges and the technique errors that fake them

Half of these items are a number you either know or you do not. The other half hand you a normal patient plus one sloppy step and ask what the reading does. Nearly every blood pressure technique error pushes the number the same way: up.

Adult pulse	60–100 bpm. Under 60 is bradycardia, over 100 is tachycardia. An irregular rhythm means an apical count at the fifth intercostal space, left midclavicular line, for a full 60 seconds.
Adult respirations	12–20 per minute. Under 12 is bradypnea, over 20 is tachypnea. Count without announcing it, because breathing is partly voluntary and a watched patient changes it.
Adult SpO2	95–100% on room air; under 90% is hypoxemia. Dark or acrylic nails, cold fingers and motion corrupt the reading, and carbon monoxide holds it falsely normal.
Adult BP (ACC/AHA)	Normal under 120 and under 80; elevated 120–129 and under 80; stage 1 130–139 or 80–89; stage 2 at or above 140 or at or above 90; crisis over 180 and/or over 120. When the two numbers land in different categories, the higher one wins.
Temperature	Fever is a measured 100.4 °F (38.0 °C) or higher (CDC). Rectal runs 0.5–1 °F above oral and is closest to core; axillary runs 0.5–1 °F below oral and is the least accurate route.
Tympanic and oral technique	Pull the pinna down and back under age 3, up and back at 3 and older. Wait 15–30 minutes after hot or cold liquids, gum or smoking before an oral reading, and always chart the route.
Pediatric ranges (AHA PALS)	Infant 1 mo–1 y: RR 30–53, HR 100–180 awake. 1–2 y: 22–37, 98–140. 3–5 y: 20–28, 80–120. 6–11 y: 18–25, 75–118. 12–15 y: 12–20, 60–100.
Cuff and position	Bladder length about 80% of arm circumference, width at least 40%. A cuff that is too small reads falsely high, and the AHA calls it the single largest source of measurement error. So do an arm below heart level, an unsupported back, crossed legs, talking and a full bladder.
Manual technique	Five minutes of quiet seated rest, and no caffeine, smoking or exercise for 30 minutes. Palpate the radial pulse and inflate 30 mm Hg past the point it disappears so an auscultatory gap cannot pose as the systolic, then deflate 2–3 mm Hg per second.
Orthostatics	Supine for 5 minutes, then standing at 1 minute and again at 3. Positive is a sustained fall of at least 20 mm Hg systolic or 10 mm Hg diastolic within 3 minutes of standing.

Where the point is lost: Miscuffing is measurable: in the Cuff(SZ) randomized trial (JAMA Internal Medicine, 2023) a regular cuff on an arm that needed a large one overstated systolic pressure by about 5 mm Hg, and on an arm that needed an extra-large one by about 20. The fix is never arithmetic. You do not subtract a correction and you do not chart the number and let the provider allow for it — you get the correct cuff, support the arm at heart level, let the patient rest, and repeat the measurement. The value that goes in the chart has to be one that was obtained correctly.