Mrs. Ford is a 32 year old female who was admitted to the neuro ICU two days ago after a fall, which caused a large epidural hematoma over the left parietal lobe. She was intubated due to a low level of consciousness to protect her airway. An External Ventricular Drain (EVD) was placed to monitor her ICP. She also has an orogastric tube, and a Foley catheter in place
Critical Thinking Check
Bloom's Taxonomy: Application
You just started your shift, what nursing assessments will be your priority at this point?
Assess ventilator and respiratory status, lung sounds, SpO2
Assess EVD system for integrity and that it is draining appropriately
Complete neuro exam including pupils, GCS, reflexes, and LOC.
Full set of vitals plus assessing IV sites for signs of infiltration or infection
Assessing foley site and urine output
Turning and assessing skin top to tail
Mrs. Ford’s vital signs are as follows: BP124/68MAP86
HR84Temp 98.9 RR16 (ventilated) ICP12
She is not on any sedation. You determine her GCS is 6, she withdraws to pain, but does not open her eyes. Her pupils are equal and reactive bilaterally, 4mm. For this hour she has put out 120 ml of urine that is clear and yellow. She is receiving normal saline at 75 mL/hour as well as tube feeds at 40 mL/hour. Her EVD is open at 15 cmH2O and draining a clear pink fluid, 6 ml this hour.
faq lesson=”true” blooms=”Application” question=”Calculate her cerebral perfusion pressure.”]
CPP = MAP – ICP
86 – 12 = 74 mmHg [/faq]
Critical Thinking Check
Bloom's Taxonomy: Analysis
Given the assessment information that you have, what are you most concerned for with this patient?
Damage to Pituitary and/or Hypothalamus glands → can cause SIADH, DI, temperature regulation issues, as well as issues with CNS functions like breathing
This patient clearly has a significant brain injury. I would be concerned for and monitoring for the following complications:
Hourly urine output for Mrs. Ford For the last 3 hours were 180 mL, 240 mL, and 440 mL. The urine is clear and barely pale yellow. Her blood pressure is 108/56, HR is 104. Her ICP is 15.
Critical Thinking Check
Bloom's Taxonomy: Analysis
What could be going on physiologically with Mrs. Ford?
This is likely Diabetes Insipidus due to the known neurological issue and the excessive output of clear, barely pale yellow urine.
Neurological damage can cause damage to the pituitary gland – causing a LACK of secretion of ADH (Antidiuretic Hormone). This means the patient can no longer retain water and therefore begins to dump water excessively – this is why the urine looks almost like water.
This will cause the blood to be super concentrated and could cause a lot of other issues because of it.
Critical Thinking Check
Bloom's Taxonomy: Analysis
What further diagnostic testing do you expect the provider to order?
Note: Polyuria WITHOUT hyperosmolality may indicate Primary Polydipsia – a condition in which patients literally drink water excessively and send themselves into a water intoxication/hypernatremic state.
Check a CMP with serum osmolality to see if she is hyperosmolar or hypernatremic
Check urine specific gravity and urine osmolarity – again this can tell us if she’s dumping lots of urine or if she’s just dumping a ton of water. Low specific gravity indiacates DI.
Continue frequent monitoring of vital signs and ICP/CPP
Re-draw labs as ordered to ensure sodium is not being corrected too quickly
After 2 days of treatment, misses Fords urine output and urine specific gravity return to Baseline. However, she continues to have a GCS between 4 + 6, and now her left pupil is 8mm and fixed. The nurse notes her respiratory rate is erratic, her ICP is 18, and her heart rate is dropping.
Critical Thinking Check
Bloom's Taxonomy: Analysis
What do you believe could be happening to Mrs. Ford at this time?
This nursing case study course is designed to help nursing students build critical thinking. Each case study was written by experienced nurses with first hand knowledge of the “real-world” disease process. To help you increase your nursing clinical judgement (critical thinking), each unfolding nursing case study includes answers laid out by Blooms Taxonomy to help you see that you are progressing to clinical analysis.We encourage you to read the case study and really through the “critical thinking checks” as this is where the real learning occurs. If you get tripped up by a specific question, no worries, just dig into an associated lesson on the topic and reinforce your understanding. In the end, that is what nursing case studies are all about – growing in your clinical judgement.
Miriam Wahrman, MSN/Ed, RNC-MNN 
Chance Reaves, MSN-Ed, RN 