6.2 Measurement & Documentation

Why Measurement Accuracy Matters

Measurements drive medical decisions. A sudden weight gain of two to three pounds in a day or five in a week can signal fluid retention from heart or kidney failure; a steady weight loss can signal poor nutrition, swallowing trouble, or illness. Low urine output can signal dehydration or kidney problems. Because the nurse and physician act on the numbers the CNA records, accuracy and honesty are non-negotiable. Measurement and documentation sit squarely in the Basic Nursing Care domain and recur on the Florida written exam.

Height and Weight

To make weights comparable over time, control every variable so that a real change — not a measurement artifact — is what you detect:

Use a chair scale, bed scale, or standing lift scale for residents who cannot stand safely; never let a resident stand on a scale unsupported if they are a fall risk. Measure height with the resident standing straight against a measuring rod, or, if bedbound, using the facility's approved tape-measure method. Never estimate a height or weight — an estimate is not a measurement and can mislead the care team.

Intake and Output (I&O)

Intake is everything the resident takes in that is liquid or liquid at room temperature: water, juice, milk, coffee, tea, soda, soup, gelatin, ice cream, sherbet, and popsicles, plus IV or tube fluids that the nurse records. Output is everything the body puts out: urine, emesis (vomit), liquid stool, and wound or drainage-tube output. (Formed stool is not measured as fluid output.)

I&O is recorded in millilitres (mL), also called cubic centimetres (cc). Memorize the common conversions — they appear directly on the exam:

To record intake, note how much of a known container the resident actually consumed — for example, half of a 240 mL cup equals 120 mL. To record output, pour urine into a graduate (measuring container) and read it at eye level on a flat surface; never estimate. Report a large imbalance (much more in than out, or vice versa), very low urine output, repeated refusals to drink, or any vomiting to the nurse.

A Worked I&O Example

A resident drinks a full 8 oz cup of coffee (240 mL), eats all of a 4 oz gelatin (120 mL), and drinks half of a 6 oz juice (6 oz = 180 mL, so 90 mL). Total intake = 240 + 120 + 90 = 450 mL. If she then voids 300 mL measured in the graduate, output for that period is 300 mL. Record each as you go, not from memory at shift's end.

Learn the standard container sizes your facility uses — a coffee cup, a juice cup, a soup bowl, a water pitcher — because the I&O sheet usually lists those sizes in millilitres so staff can record consistently. If a resident is on a fluid restriction (a capped daily intake ordered for heart or kidney conditions) or push fluids (encouraged to drink more), the CNA follows that order and reports when the resident is far above or below the goal. Reduced intake combined with reduced output is an early warning of dehydration that the nurse needs promptly.

Documentation Standards

Florida CNAs document care that was actually given, when it was given, exactly as observed. Charting is a legal record; the rule of thumb is "if it was not documented, it was not done."

• Be prompt: record as soon as the task is finished, not hours later from memory.
• Be objective: write what you saw, did, and measured — not opinions or conclusions. Write "ate 50% of lunch," not "resident was being difficult."
• Be accurate: record the real number; do not round to make the chart look tidy.
• Never pre-chart: never document care before performing it — this is falsification, a serious offense that can cost your CNA registry standing and your job.
• Correct errors properly: per facility policy, draw a single line through the error, write the correction, and initial and date it. Never erase, scribble out, or use correction fluid.
• Use only approved abbreviations, and report first, then document abnormal findings — reporting an urgent change should never wait on paperwork.
• Protect confidentiality: charts and electronic records are protected health information under HIPAA; never discuss a resident's measurements or condition with anyone not involved in their care, and keep screens and paper records out of public view.

Most long-term-care facilities now use electronic health records (EHRs) in addition to or instead of paper. The same principles apply: log in under your own credentials, never share a password, chart promptly and accurately, and use the system's correction feature rather than deleting an entry. Whether on paper or screen, the chart is the legal account of the care a resident received.

Exam Tip

If an answer choice involves estimating, charting ahead, recording care that did not happen, or recording an opinion, it is wrong. The correct documentation answer is always timely, factual, objective, and accurate, and it follows reporting — not the other way around for emergencies.