Nursing Field Notes / Renal + Fluid · Fundamentals of Nursing

FVO vs. FVD ⚖️

Signs & symptoms · head-to-toe · fluid volume OVERLOAD vs. DEFICIT

NG-207 RENAL + FLUID ADHD-friendly visual edition

Two opposite patients, one set of body systems. Hypervolemia = HIGH fluid volume = a big & bulging body. Hypovolemia = LOW fluid volume = a low & little body. Learn one column properly and the other is simply every arrow flipped.

📄 Simple Nursing original — opens in Drive →

🎈 FVO = BIG & BULGINGBP ⬆ · bounding pulse · JVD ⬆ · CVP ⬆ · edema · crackles · weight ⬆

🍇 FVD = LOW & LITTLEBP ⬇ · thready pulse · flat veins · CVP ⬇ · tenting skin · weight ⬇

🧪 Low when LiquidyFVO dilutes every lab. High when Dry — FVD concentrates every lab.

⚖️ 2–3 lb / 5 lbin 1 day / in 7 days = report. Weight gain = water gain.

🎈

SIDE A · FLUID VOLUME OVERLOAD

HYPERVOLEMIA

HIGH fluid volume · big & bulging body · everything you measure goes UP except the labs.

💧 Which way is the water moving?

🧠 “BIG & BULGING BODY = BIG fluid volume.” The arrow points out of the pipe, into the tissue — that single arrow explains the edema, the crackles and the bulging neck veins all at once.

🧠 Neuromuscular · FVO

Headache
Weakness
Lethargy → coma
ALOC — altered level of consciousness, “mental status changes”
Seizures if sodium falls fast

Why: extra water dilutes the sodium → water follows into brain cells → cerebral edema.

🧠 “Waterlogged brain gets sleepy.” Headache first, then the level of consciousness slides down.

🫀 Cardiovascular · FVO

High blood pressure TEST TIP — deadly hypertension at systolic 140; hypertensive CRISIS at systolic 180 with STROKE RISK
Increased central venous pressure (CVP) — normal ≈ 2–6 mmHg
Bounding pulses
Big distended veins · jugular vein distention (JVD)

🧠 “Full tank → high pressure → fat veins → bounding pulse.” Say it as one chain; it is always the same chain.

🖐️ Integumentary (skin) · FVO

Periorbital edema — puffy eyelids, worst in the morning
Pitting edema (think “water-bed skin”) from hydrostatic pressure
Pale, cool skin; taut and shiny over the swelling
Sacral edema in bedbound clients — check where they lie, not just the ankles

🧠 “Water-bed skin.” Press it and the dent stays — like a memory-foam mattress holding your handprint.

🫁 Respiratory · 🚽 renal · 🍽️ GI · FVO

RESPIRATORY: rapid respiratory ratedyspnea & orthopneaRALES — moist crackles = fluid in the lungsPULMONARY EDEMA

RENAL & URINARY: increased urine output as the kidneys dump the extra — but decreased urine output when renal failure is the reason they are overloaded in the first place.

GASTROINTESTINAL: increased motility — diarrheahepatomegaly (enlarged liver)ascites (abdominal fluid)

🧠 “Wet lungs, wet gut, wet belly.” Rales + diarrhea + ascites — the water shows up in every hollow space it can reach.

🧪 LAB VALUES · FVO — “LOW when LIQUIDY”

🚨 LOW SODIUM Na⁺ — hyponatremia, below 135 mEq/L → RISK FOR BRAIN DAMAGE. Water shifts into brain cells and swells them.

🧠 “Urine LOW when Liquidy.” Dilute blood → dilute urine → low specific gravity. LOW gravity = LOW weight — watery urine literally weighs less than concentrated urine.

🍇

SIDE B · FLUID VOLUME DEFICIT

HYPOVOLEMIA

LOW fluid volume · low & little body · everything you measure goes DOWN except the heart rate and the labs.

💧 Which way is the water moving?

🧠 “LOW & LITTLE BODY = LOW fluid volume.” The arrows point out of the body — urine, sweat, vomit, stool, blood, burned skin.

🧠 Neuromuscular · FVD

Weakness & paresthesias (numbness, tingling)
Mental status changes — confusion, especially in older adults
Dizziness, light-headedness, syncope
Extreme thirst

Why: less volume → less perfusion to the brain, plus rising sodium pulls water out of brain cells.

🧠 “New confusion in Grandma = check her fluids.” Dehydration is one of the most common reversible causes of sudden confusion in older adults.

🫀 Cardiovascular · FVD

Low blood pressure TEST TIP — deadly hypotension
Orthostatic hypotension — light-headed & dizziness upon standing (systolic drops ≥20 or diastolic ≥10 mmHg)
Decreased central venous pressure (CVP)
Weak, thready pulses
Flat neck & hand veins
Tachycardia — pulse over 100

🧠 “Empty tank → fast pump → flat veins → thready pulse.” The exact mirror of the FVO chain.

🖐️ Integumentary (skin) · FVD

Sunken eyes (and sunken fontanel in infants)
Dry skin — poor turgor & tenting
Dry mucous membranes (MM) — dry tongue, dry axilla, no tears
Increased body temperature — less fluid to carry heat away

⚠️ In older adults, test turgor over the sternum or forehead — arm skin tents normally with age.

🧠 “Sucked in & shrivelled up, like a dried-out raisin in the sun.”

🫁 Respiratory · 🚽 renal · 🍽️ GI · FVD

RESPIRATORY: rapid respiratory ratedeep, rapid Kussmaul breathing when the cause is DKAclear lungs — no crackles

RENAL & URINARY: decreased urine output — under 30 mL/hr, dark and concentrated. Exception: when the cause is DI, DKA or diuretics, output is high on the way into the deficit.

GASTROINTESTINAL: decreased motility — CONSTIPATIONdiminished bowel soundsthirst, nausea, anorexia

🧠 “Dry gut = slow gut.” No water in the bowel means hard stool and quiet bowel sounds — the mirror image of the overloaded client's diarrhea.

🧪 LAB VALUES · FVD — “APPEAR HIGH when DRY”

🚨 HIGH SODIUM Na⁺ — hypernatremia, over 145 mEq/L → RISK FOR BRAIN BLEEDING. Brain cells shrink and pull away from their vessels, tearing them.

🧠 “Urine HIGH when Dry.” Concentrated blood → concentrated urine → high specific gravity. HIGH gravity = HIGH weight — the more solute packed in, the heavier the urine.

⚖️

TELL THEM APART

SYSTEM BY SYSTEM

The whole page on one screen. Read a row left to right and say the two opposites out loud.

📋 The master head-to-toe table

🧠 Neuromuscular

🎈 FLUID VOLUME OVERLOAD	🍇 FLUID VOLUME DEFICIT
Headache · weakness	Weakness & paresthesias
Lethargy → coma	Dizziness · light-headedness · syncope
ALOC — altered level of consciousness, “mental status changes”	Mental status changes — new confusion in the elderly

🫀 Cardiovascular

🎈 OVERLOAD	🍇 DEFICIT
HIGH blood pressure — deadly hypertension (140 systolic); HTN crisis 180 systolic = STROKE RISK	LOW blood pressure — deadly hypotension; orthostatic hypotension (light-headed & dizzy on standing)
Increased CVP (normal ≈ 2–6 mmHg)	Decreased CVP
Bounding pulses	Weak, thready pulses
Big distended veins · JVD	Flat neck & hand veins
Rate may be normal or elevated; S3 gallop	Tachycardia — pulse over 100

🖐️ Integumentary (skin)

🎈 OVERLOAD	🍇 DEFICIT
Periorbital edema	Sunken eyes (sunken fontanel in infants)
Pitting edema — “water-bed skin” — from hydrostatic pressure	Dry skin — poor turgor & tenting
Pale, cool skin; taut and shiny	Dry mucous membranes (MM)
Sacral edema when bedbound	Increased body temperature

🚽 Renal & urinary

🎈 OVERLOAD	🍇 DEFICIT
Increased urine output — kidneys dumping the excess	Decreased urine output — under 30 mL/hr, dark & concentrated
Decreased output if renal failure is the cause of the overload	Increased output if the CAUSE is DI, DKA or diuretics
Urine looks pale and watery	Urine looks dark and strong

🫁 Respiratory

🎈 OVERLOAD	🍇 DEFICIT
Rapid respiratory rate, dyspnea, orthopnea	Rapid respiratory rate (compensating)
RALES (moist crackles) — fluid in the lungs	Lungs stay CLEAR — no crackles
PULMONARY EDEMA — pink frothy sputum, falling SpO₂	Deep, rapid Kussmaul breathing when the cause is DKA

🍽️ Gastrointestinal

🎈 OVERLOAD	🍇 DEFICIT
Increased motility — diarrhea	Decreased motility — constipation
Hepatomegaly (enlarged liver)	Diminished bowel sounds
Ascites (abdominal fluid)	Thirst, nausea, anorexia

🧪 Lab values

🎈 OVERLOAD — “low when liquidy”	🍇 DEFICIT — “appear high when dry”
DECREASED osmolality (275–295 mOsm/kg)	INCREASED osmolality
DECREASED hematocrit (HCT)	INCREASED hematocrit (HCT)
DECREASED blood urea nitrogen (BUN) (10–20 mg/dL)	INCREASED BUN — BUN:creatinine over 20:1
DECREASED electrolytes	INCREASED electrolytes
LOW sodium Na⁺ — hyponatremia <135 mEq/L → risk for BRAIN DAMAGE	HIGH sodium Na⁺ — hypernatremia >145 mEq/L → risk for BRAIN BLEEDING
DECREASED urine specific gravity — below 1.005	INCREASED urine specific gravity — above 1.030

⚖️ Weight

🎈 OVERLOAD	🍇 DEFICIT
WEIGHT GAIN = WATER GAIN	WEIGHT LOSS = WATER LOSS
Report either direction: 2–3 lb in 1 day · 5 lb in 7 days · 1 kg = 1 L = 2.2 lb

🧠 Read every row as one sentence: “Overload is big, bulging, bounding and diluted. Deficit is little, flat, thready and concentrated.” Eight adjectives, whole page.

📏 Same scale, two patients — where each one sits

Five different labs, one pattern: the blue marker (overload) always sits low, the red marker (deficit) always sits high.

🧠 “Blue is dilute, red is concentrate.” You never have to memorize five lab directions — memorize one.

🚽 Urine tells you in 3 seconds

🧠 “Urine LOW when Liquidy · Urine HIGH when Dry.” Specific gravity is literally how heavy the urine is compared with water — more solute, heavier number.

⚖️ The scale, both directions

🧠 “The scale doesn't lie and it doesn't wait.” It moves before the crackles appear and before the BP drops.

🧭 Which one is it? — a 5-second decision path

🩺 Look at the neck veins first

▼

Distended / bulging (JVD) → think OVERLOAD · Flat → think DEFICIT

▼

🫁 Listen to the lung bases. Crackles = overload. Clear = deficit.

▼

⚖️ Check the weight trend. Up = overload. Down = deficit.

▼

🧪 Confirm with the labs. All LOW = overload. All HIGH = deficit.

Veins → lungs → scale → labs. Four checks, in that order, and you have your answer before the chart loads.

🧠 “Necks, chest, scale, serum.” Free, fast, and available at the bedside in that order.

🚨 NCLEX traps on this comparison

“Increased urine output” appears on BOTH sides. In FVO it means the kidneys are unloading. In FVD it means the cause (DI, DKA, diuretics) is making the deficit. Read what came first.
Third spacing looks like both at once — weight UP but BP down, HR up, urine down. Treat the vital signs; the client is intravascularly dry.
Both hyponatremia and hypernatremia are brain problems. LOW Na⁺ = brain swells (damage). HIGH Na⁺ = brain shrinks and vessels tear (bleeding).
A normal BP does not rule out deficit. Tachycardia and falling urine output come first; BP falls last.
Skin turgor is unreliable in older adults. Use weight, urine output, mucous membranes and mental status instead.
You can create the opposite problem. Over-diuresing an FVO client makes FVD; over-hydrating an FVD client makes FVO. Reassess after every intervention.

🧠 “Same word, opposite reason.” Whenever a sign appears in both columns, the exam is asking you why it is there, not whether it is there.

⚡

QUICK RECALL

SAY IT OUT LOUD

🎈 HYPERvolemiaHIGH fluid volume · BIG & BULGING BODY

🍇 HYPOvolemiaLOW fluid volume · LOW & LITTLE BODY

🧪 Liquidy vs DryLow when Liquidy · High when Dry — all 5 labs, same direction

🧠 Na⁺ 135 / 145<135 brain DAMAGE (swells) · >145 brain BLEEDING (shrinks)

🫀 Bounding vs threadyJVD + ↑CVP + high BP ⟷ flat veins + ↓CVP + low BP

🫁 Crackles vs clearRales & pulmonary edema ⟷ clear lungs, rapid rate

🍽️ Diarrhea vs constipation+ ascites & hepatomegaly ⟷ diminished bowel sounds

🧭 Necks·chest·scale·serumthe 4-step bedside decision path

🎯 Cover & check — 7 rapid-fire questions

Q1: Bounding pulses, JVD, crackles and a 3 lb overnight weight gain — which one and why?

Fluid volume OVERLOAD (hypervolemia). Extra volume raises pressure in the vessels, distends the veins and pushes fluid into the lungs. Weight gain = water gain.

Q2: Urine specific gravity is 1.002. Overload or deficit?

Overload. Normal is 1.005–1.030; below 1.005 the urine is dilute and watery. "Urine LOW when Liquidy — low gravity = low weight."

Q3: Which sodium abnormality goes with which fluid problem, and what is the brain risk?

FVO → hyponatremia below 135 mEq/L → water enters brain cells → cerebral edema and BRAIN DAMAGE. FVD → hypernatremia above 145 mEq/L → brain cells shrink and vessels tear → BRAIN BLEEDING.

Q4: Why do BUN and hematocrit both rise in deficit when nothing was added?

Hemoconcentration — the same solutes and red cells are suspended in less plasma, so they only APPEAR high. "Lab values appear high when dry."

Q5: Give the GI findings for each side.

FVO: increased motility — diarrhea, plus hepatomegaly and ascites. FVD: decreased motility — constipation, diminished bowel sounds, thirst.

Q6: Client's weight is up 4 lb but the BP is 86/48, HR 122, urine 15 mL/hr. Which column?

Trick question — third spacing. Total body water is up (the scale) but the INTRAVASCULAR space is empty (the vital signs). Treat as fluid volume deficit intravascularly, and expect a later reabsorption phase with overload risk.

Q7: What is the fastest bedside sequence to sort FVO from FVD?

Necks → chest → scale → serum. Neck veins distended or flat; lungs crackly or clear; weight trending up or down; then confirm with labs — all low (overload) or all high (deficit).