Imagine the charge nurse asks for Mrs. Higgins’ current totals at the end of a busy shift. Do you have the numbers ready? Intake and Output (I&O) is one of the most critical daily tasks you will perform, acting as a window into your resident’s kidney function and fluid balance.
What is Intake and Output?
Intake and Output (commonly called I&O) is the precise recording of all fluids a resident consumes and excretes over a 24-hour period. Intake includes everything liquid: water, coffee, tea, soup, ice cream, and gelatin. Output primarily refers to urine, but also includes vomit, diarrhea, or wound drainage. It is usually measured in milliliters (mL) or cubic centimeters (cc).
Why I&O Matters in Your Daily Care
Accurate I&O monitoring helps the medical team determine if a resident is dehydrated, retaining fluid, or if their kidneys are working properly. For residents with heart failure or kidney disease, strict fluid balance can prevent serious complications like fluid overload in the lungs. If the numbers don’t match up—meaning a resident is drinking a lot but not peeing—it is a red flag that requires immediate attention.
What You’ll See During Your Shift
You will see graduated collection containers (known as “hats”) placed in toilet bowls or on commodes to catch urine. You will also measure pitchers of water at meal times and track how much a resident actually drinks. Estimating is not enough; you must measure. You might notice a resident’s output decreasing while their intake remains high, or vice versa.
“Nurse Ben, I just finished Mr. Alvarez’s I&O for the shift. His intake is 800 mL, but his output is only 300 mL since 7 AM. He seems a little swollen in his ankles today.”
Common Pitfall & Pro Tip
⚠️ Pitfall: Recording “half a glass” or “a few sips” in the chart. Vague terms make it impossible for the nurse to calculate accurate fluid balance.
Pro Tip: Keep a measuring cup in the bathroom and at the bedside. Measure before discarding any liquid or emptying a bedpan. Remember that ice melts into half its volume, so record 100 mL of ice as 50 mL of water intake.
Memory Aid for I&O
Think “In & Out = The Currency of Kidneys.” Just like a bank account tracks money to prevent bankruptcy, tracking I&O prevents “fluid bankruptcy” in the body.
State Test Connection
I&O is a mandatory skill for both the clinical skills exam and the written portion of state tests (Prometric/Pearson VUE). You will be tested on your ability to measure accurately and record the data correctly.
Related Care Concepts
Mastering I&O is directly linked to monitoring dehydration and fluid volume excess. It connects closely with vital signs, as blood pressure can drop with dehydration or rise with fluid retention. It also relates to elimination, as changes in urinary habits often signal underlying health issues.
Quick Reference
✓ Key items to measure: All liquids, ice cream, gelatin, urine, vomit, diarrhea ✓ When to report: Output significantly less than intake, or no urine for 6-8 hours ✓ Care reminders: • Measure at the bedside immediately • Record ice as half its volume • Do not discard urine before measuring • Document immediately to avoid forgetting
Bottom line: Precise I&O records protect your residents from dangerous fluid imbalances. When you measure carefully, you are providing the data the medical team needs to save lives.