Rapid weak pulse, falling blood pressure, cool clammy skin, or altered mental status — hypovolemic shock; call the rapid response team now.
Before you read
Test yourself first: 5 questions
Question 1 of 5
A client is admitted with severe dehydration. Which IV fluid does the nurse anticipate initially?
Answer: A. Initial resuscitation for hypovolemia/dehydration uses an isotonic crystalloid (0.9% normal saline or Lactated Ringer's) to expand intravascular volume. Hypotonic fluids alone don't rapidly restore volume.
Question 2 of 5
A client has fluid volume deficit (dehydration). Which assessment finding is expected?
Answer: B. Dehydration → tachycardia, hypotension, poor skin turgor, dry mucous membranes, concentrated (dark) urine, and weight loss. Bounding pulses and crackles suggest overload instead.
Question 3 of 5
A nurse is caring for a client with severe dehydration (fluid volume deficit). Which finding indicates the condition is worsening and requires immediate intervention?
Answer: A. Worsening hypovolemia leads to decreased circulating volume and shock. A blood pressure of 84/50 with a thready pulse of 124 indicates compensatory tachycardia and hypotension from inadequate perfusion, requiring immediate fluid resuscitation. Moist mucous membranes and a normal output would indicate improvement.
Question 4 of 5
A client with severe Crohn disease has developed a fistula between the bowel and the skin. Which is the priority nursing assessment related to this complication?
Answer: A. Enterocutaneous fistulas drain intestinal contents externally, leading to significant losses of fluid and electrolytes plus risk of malnutrition and skin breakdown; monitoring fluid and electrolyte balance is the priority because large losses can cause dehydration and dangerous imbalances. Skin protection and nutrition are also important, but the immediate priority is detecting fluid and electrolyte deficits. This complication commonly requires bowel rest and parenteral nutrition.
Question 5 of 5
A client with HHS has a serum glucose of 820 mg/dL and a serum osmolality of 340 mOsm/kg. Which clinical manifestation does the nurse most expect?
Answer: B. The hallmark of HHS is severe hyperosmolarity and dehydration, which impair cerebral function and produce altered mental status ranging from confusion to seizures and coma. Because ketosis is minimal, fruity breath and Kussmaul breathing are not expected. The osmotic diuresis causes profound fluid volume deficit rather than overload.
Keep the streak going with more questions like these, each with a full rationale.
What is fluid volume deficit (dehydration)?
Causes include vomiting, diarrhea, hemorrhage, heavy sweating, fever, excess urination from diuretics or illness, and poor intake. As volume falls, the heart rate rises and urine becomes scant and concentrated; if losses continue, blood pressure drops and organs are underperfused. The nurse's job is to spot early signs, such as tachycardia, orthostatic hypotension, and low urine output, before the client slides into hypovolemic shock.
Key points to remember
- Vital signs: tachycardia, weak thready pulse, hypotension, and orthostatic (postural) hypotension.
- Urine output drops below 30 mL/hr; urine is dark and concentrated with high specific gravity.
- Thirst, dry mouth and skin, poor skin turgor, furrowed tongue, fatigue, dizziness, flat neck veins, sunken eyes, and slow capillary refill.
- Acute weight loss is the most sensitive sign: 1 liter of fluid equals about 1 kg (2.2 lb).
- Hemoconcentration raises hematocrit, BUN, and serum osmolality.
- Higher risk: older adults (thirst sense can fade with age), infants and young children (more vomiting and diarrhea), chronic illness such as diabetes, kidney disease, or cystic fibrosis, diuretics, and hot weather or exercise.
- Infant signs: dry mouth and tongue, crying without tears, no wet diaper for 3 hours or more, sunken eyes, unusual sleepiness, or irritability.
Signs & symptoms
- ↑ HR, ↓ BP, orthostatic
- Dry mucosa, poor skin turgor
- ↓ urine, ↑ urine concentration
- Weight loss, flat neck veins
Nursing priorities
- Assess vital signs including orthostatic blood pressure, level of consciousness, and urine output, because they reveal falling perfusion.
- Replace fluid and electrolytes: oral rehydration if tolerated, isotonic IV fluids (0.9% NaCl or lactated Ringer's) for moderate to severe deficit, because restoring circulating volume restores perfusion.
- Start fall precautions, because orthostatic hypotension and dizziness cause falls.
- Treat the cause as ordered (control vomiting or diarrhea, stop bleeding, hold diuretics), because replacement fails while losses continue.
- Keep strict intake and output and daily weights, and reassess for urine output of at least 30 mL/hr, rising blood pressure, and brisk capillary refill.
Labs & values
Worked example
- Cue: An older adult with two days of diarrhea has a rising heart rate, dizziness and a blood pressure drop on standing, dark urine, and output under 30 mL/hr.
- Meaning: Fluid volume deficit with reduced perfusion.
- Action: Start fall precautions, notify the provider, give isotonic IV fluid as ordered, and keep strict intake and output and daily weights.
- Evaluation: Urine output is at least 30 mL/hr, the orthostatic drop resolves, and mucous membranes are moist.
Patient teaching
- Drink more when you are sick, have a fever, exercise, or are out in the heat. Limit sugary drinks and caffeine.
- Older adults: drink on a schedule, even if you do not feel thirsty.
- For vomiting or diarrhea, use an oral rehydration drink. If keeping liquids down is hard, take small sips of water or suck on ice chips.
- Get care for dizziness, dark urine, very little urine, confusion, or fainting.
Common mistakes
- Relying on thirst in older adults, whose sense of thirst may fade.
- Checking only a supine blood pressure and missing an orthostatic drop.
- Reading a high hematocrit or BUN as a primary blood or kidney problem without considering hemoconcentration from fluid loss.
- Choosing 'Risk for deficient fluid volume' when signs are already present. 'Risk for' fits only when risk factors exist without signs.
Red flags: report now
- Rapid weak pulse, falling blood pressure, cool clammy skin, or altered mental status — hypovolemic shock; call the rapid response team now.
- Urine output under 30 mL/hr despite fluids — notify the provider (poor perfusion or kidney injury).
- Confusion, fainting, rapid breathing, or no urine — emergency; escalate immediately.
- Infant with no wet diaper for 3 hours or more plus unusual sleepiness — needs urgent medical evaluation.
References
Clinical references for this topic
