Eleanor Thompson
Admission Snapshot
Chief Complaint
“My mother has been very confused and weak for the past few days. She fell this morning trying to get to the bathroom.”
Eleanor is brought to the hospital by her son after approximately three days of progressive confusion and generalized weakness. This morning, she fell while attempting to walk to the bathroom.
Her recent history of small cell lung cancer and current chemotherapy raise concern for a malignancy-associated electrolyte disturbance, including possible SIADH.
Patient Profile
5 ft 4 in (163 cm) • 145 lb (65.8 kg) • BMI 24.9
Isolation Status: Standard Precautions
Medical History
- Small cell lung cancer diagnosed 3 months ago
- Currently receiving chemotherapy
- Hypertension diagnosed 10 years ago
- Osteoarthritis
- Previous smoking history
- Stopped smoking approximately 3 months ago
Home Medications
- Amlodipine 5 mg PO daily — hypertension.
- Cisplatin / Etoposide chemotherapy regimen — treatment for small cell lung cancer; last treatment approximately 1 week ago.
- Acetaminophen 650 mg PO every 6 hours PRN — pain.
- Ondansetron 4 mg PO every 8 hours PRN — nausea.
Recent History
Eleanor was diagnosed with small cell lung cancer approximately three months ago and is undergoing active chemotherapy with cisplatin and etoposide. Her most recent treatment was approximately one week ago.
Over the last three days, her son has noticed progressive confusion, generalized weakness, and increasing difficulty safely completing normal activities. Eleanor has reportedly been drinking her usual amount of water and taking her medications as prescribed.
This morning she became weak while walking to the bathroom and fell. Her son reports no known loss of consciousness, focal neurologic deficit, fever, or preceding severe headache.
Emergency Contact
James Thompson • Son
589-216-XXXX
Insurance
Medicare
Current Care Status
Admitted from the Emergency Department to the Step-Down Unit for close neurologic and electrolyte monitoring during treatment of altered mental status with suspected SIADH and severe symptomatic hyponatremia. Patient is located in Room 412, is a Full Code, and remains on Standard Precautions.
Patient Timeline
Eleanor is admitted from the Emergency Department with progressive confusion, generalized weakness, and a recent fall. Testing reveals severe hypotonic hyponatremia with inappropriately concentrated urine and clinical euvolemia, raising concern for SIADH associated with her small cell lung cancer.
Chief Complaint
“I've been feeling weak, and my son says I've been confused. I fell this morning trying to get to the bathroom.”
History of Present Illness
Eleanor Thompson is a 72-year-old woman brought to the Emergency Department by her son at 0815 for a three-day history of progressive confusion and generalized weakness. She is now admitted to the Step-Down Unit for treatment of symptomatic severe hyponatremia.
Her son reports that she has become increasingly forgetful, has required repeated prompting with routine activities, and appeared unsteady while walking this morning. She became weak while attempting to reach the bathroom and fell. No known loss of consciousness occurred.
Eleanor was diagnosed with small cell lung cancer approximately three months ago and is receiving cisplatin and etoposide chemotherapy. Her most recent treatment was approximately one week ago. Son reports intermittent post-chemotherapy nausea but no persistent vomiting or diarrhea.
She has reportedly continued drinking her usual amount of water and has not intentionally increased her fluid intake. No fever, severe headache, seizure activity, or focal neurologic symptoms were reported prior to arrival.
Because of the fall and altered mental status, CT of the head was completed in the Emergency Department before treatment was started and showed no acute intracranial abnormality.
Past Medical History
- Small cell lung cancer diagnosed approximately 3 months ago
- Active cisplatin / etoposide chemotherapy
- Hypertension diagnosed approximately 10 years ago
- Osteoarthritis
- Former smoker
- Sulfa drug allergy — rash
Family History
- No known family history of chronic hyponatremia or endocrine disorder
- No known hereditary renal disorder
Social History
- Former cigarette smoker
- Stopped smoking approximately 3 months ago after lung cancer diagnosis
- Son, James Thompson, actively involved in care and currently at bedside
- No reported recent excessive alcohol use
Review of Systems
Constitutional: Generalized weakness and fatigue. No reported fever or chills.
Neurologic: Progressive confusion over approximately three days. Recent fall. Denies severe headache. No witnessed seizure or focal weakness.
Cardiovascular: Denies chest pain, palpitations, or syncope.
Respiratory: Denies acute shortness of breath.
Gastrointestinal: Intermittent nausea following chemotherapy. No current vomiting or diarrhea.
Genitourinary: No dysuria reported.
Musculoskeletal: Generalized weakness with recent fall.
Physical Examination
General: Elderly woman, awake but confused. No acute cardiopulmonary distress.
HEENT: Normocephalic and atraumatic. Mucous membranes moist.
Cardiovascular: Regular rate and rhythm. Normal S1 and S2. No murmur appreciated.
Respiratory: Respirations even and nonlabored. Lungs clear to auscultation bilaterally.
Abdomen: Soft, nondistended, and nontender.
Neurologic: Alert but confused. Oriented to person only. Follows simple commands with repetition. Speech clear. Strength approximately 4/5 bilaterally. Deep tendon reflexes 2+. No focal neurologic deficit identified.
Skin: Warm and intact. No significant bruising, laceration, or other obvious injury identified following reported fall.
Volume Status: Clinically euvolemic. No orthostatic symptoms, peripheral edema, jugular venous distention, or other evidence of significant volume depletion or overload.
Labs
Laboratory studies were drawn in the Emergency Department at 0845. Initial sodium is 118 mEq/L with serum osmolality 245 mOsm/kg. Urine remains inappropriately concentrated with urine osmolality 450 mOsm/kg, urine sodium 65 mEq/L, and urine specific gravity 1.025.
Potassium 3.8 mEq/L, chloride 88 mEq/L, CO₂ 26 mEq/L, BUN 12 mg/dL, creatinine 0.8 mg/dL, and glucose 98 mg/dL.
TSH is 2.1 mIU/L, free T4 is 1.1 ng/dL, and serum cortisol is 15 mcg/dL. Serum uric acid is 2.8 mg/dL.
CBC demonstrates WBC 3.4 ×10³/mcL, ANC 1.5 ×10³/mcL, hemoglobin 10.8 g/dL, and platelets 142,000/mm³. Findings are consistent with recent chemotherapy but do not currently meet criteria for severe neutropenia.
Serum sodium will be rechecked every 2 hours during active correction, with the first post-treatment value due at 1200.
Diagnostics
CT head without contrast, completed in the Emergency Department at 0930, demonstrates no acute intracranial hemorrhage, mass effect, or other acute intracranial abnormality.
Assessment
Severe hypotonic hyponatremia with moderately severe neurologic symptoms including confusion, weakness, and recent fall.
Laboratory findings demonstrate low serum osmolality with inappropriately concentrated urine, elevated urine sodium, low uric acid, preserved renal function, and clinical euvolemia. Thyroid and adrenal testing do not currently suggest hypothyroidism or adrenal insufficiency as the cause.
Overall presentation is highly consistent with SIADH, with small cell lung cancer the most likely underlying driver. Recent chemotherapy, nausea, and treatment-related physiologic stress may further stimulate ADH release.
Plan
- Admit to Step-Down Unit for closer neurologic and electrolyte monitoring.
- Administer 3% sodium chloride 150 mL IV over 20 minutes.
- Reassess neurologic symptoms and serum sodium after hypertonic saline.
- Initial treatment goal is a controlled rise sufficient to improve neurologic symptoms, not immediate normalization of serum sodium.
- Check serum sodium every 2 hours during active correction.
- Target total sodium correction no greater than 8 mEq/L during the first 24 hours given concern for chronicity and possible increased osmotic demyelination risk.
- If sodium rises faster than intended, stop active correction and notify provider immediately. Consider D5W and/or desmopressin for controlled re-lowering per specialist guidance.
- Once acute neurologic symptoms stabilize, maintain fluid restriction of 800 mL per 24 hours.
- Bedside swallow screen before any oral intake.
- Strict intake and output.
- Daily morning weight using the same scale.
- Seizure precautions.
- Fall precautions and assisted mobility.
- Neurologic assessments every 2 hours during active correction.
- Endocrinology consultation.
- Oncology consultation regarding paraneoplastic SIADH and future chemotherapy management.
Provider Information
Dr. Tessa Monroe, NP
Critical Care • Step-Down Service
1015: Patient received from the Emergency Department to the Step-Down Unit for severe symptomatic hyponatremia and altered mental status. Patient is awake but confused and oriented to person only. She follows simple commands with repeated direction and requires frequent reorientation. Patient states, “I just feel so weak.”
Son, James Thompson, remains at bedside and assists with history and reassurance. No seizure activity, severe headache, dysarthria, or focal weakness observed.
Seizure and fall precautions initiated. Bed maintained in lowest position with alarm active. Suction and oxygen equipment available at bedside. Non-slip footwear applied and patient instructed not to get up without assistance. Call light within reach.
Two peripheral IVs present: 20-gauge right forearm and 22-gauge left forearm. Both sites patent, clean, dry, and intact without redness, swelling, pain, or infiltration.
3% sodium chloride 150 mL initiated through the 20-gauge right forearm IV to infuse over 20 minutes per order. IV site monitored closely throughout infusion.
Admission weight obtained: 65.8 kg. Daily morning weights ordered using the same scale. Strict intake and output initiated.
1035: 3% sodium chloride infusion completed. Patient tolerated infusion without IV site complication. Neurologic status unchanged from admission assessment.
1100: Bedside swallow screen completed prior to oral intake. Patient followed commands, managed secretions, and swallowed test volumes without coughing, wet voice, or other signs of aspiration. Regular diet started. Fluid restriction of 800 mL per 24 hours initiated. Patient and son instructed that beverages, ice, gelatin, soup, and other liquids count toward the daily fluid allowance.
1200: Repeat serum sodium 120 mEq/L, an increase of 2 mEq/L from 118 mEq/L. Dr. Monroe notified of result. Patient more attentive during conversation but remains oriented to person only. No seizure activity or new neurologic deficit. Sodium checks every 2 hours continue.
1400: First four hours of strict intake and output (1000–1400): oral intake 240 mL and urine output 150 mL. Urine appears dark and concentrated. Neurologic checks every 2 hours remain stable without new deficit. Both IV sites remain clean, dry, and intact. Provider to be notified for seizure activity, worsening mental status, new focal deficit, sudden increase in urine output, or sodium correction exceeding ordered parameters.
Consultant
Dr. Fatima Almasi, NP
Endocrinology
Reason for Consultation
Severe hypotonic hyponatremia with suspected SIADH in patient with small cell lung cancer.
Impression
Findings strongly support SIADH: serum sodium 118 mEq/L, serum osmolality 245 mOsm/kg, urine osmolality 450 mOsm/kg, urine sodium 65 mEq/L, urine specific gravity 1.025, low serum uric acid, preserved renal function, and clinical euvolemia.
Thyroid and cortisol testing do not currently suggest an alternative endocrine cause of hyponatremia. Small cell lung cancer is the most likely underlying source of inappropriate ADH activity.
Recommendations
- Agree with the 3% sodium chloride 150 mL bolus administered 1015–1035 for current neurologic symptoms.
- Reassess symptoms and the 1200 serum sodium before additional hypertonic saline is considered.
- Check serum sodium every 2 hours during active correction.
- Avoid sodium increase greater than 8 mEq/L in 24 hours for this patient.
- If overcorrection develops, stop active correction and consider D5W and/or desmopressin with specialist guidance.
- Continue 800 mL/day fluid restriction after acute stabilization.
- Continue strict intake/output and daily weights.
- Monitor urine output closely for sudden water diuresis, which may precede rapid sodium correction.
- Coordinate with oncology regarding treatment of underlying small cell lung cancer.
| Order Type | Order Details | Priority | Ordered By | Status | Comments |
|---|---|---|---|---|---|
| Level of Care | Admit to Step-Down Unit from Emergency Department | Urgent | Dr. Tessa Monroe, NP | Completed | Close neurologic and electrolyte monitoring required during active sodium correction. |
| Medication | Sodium chloride 3%, 150 mL IV over 20 minutes once | Stat | Dr. Tessa Monroe, NP | Completed | Indication: symptomatic severe hyponatremia. Infused 1015–1035. Reassess neurologic symptoms and serum sodium after dose before considering additional therapy. |
| Laboratory | Serum sodium every 2 hours during active correction | Stat | Dr. Tessa Monroe, NP | Active | 1200 result: 120 mEq/L. Notify provider for unexpectedly rapid correction or total rise approaching 8 mEq/L within 24 hours. |
| Medication / Rescue | If sodium overcorrection occurs: stop active sodium correction and notify provider; D5W and/or desmopressin may be initiated per specialist order | Stat PRN | Dr. Tessa Monroe, NP | Conditional | Used to prevent or treat excessive sodium correction. Requires immediate provider/endocrinology direction. |
| Fluid Restriction | Restrict total oral fluid intake to 800 mL per 24 hours after acute stabilization | Routine | Dr. Tessa Monroe, NP | Active | Started 1100. Include water, beverages, ice, gelatin, soup, and other liquid foods. |
| Nursing | Strict intake and output | Routine | Dr. Tessa Monroe, NP | Active | Document all oral intake and urine output. Report sudden increase in urine output. |
| Nursing | Daily weight every morning using same scale | Routine | Dr. Tessa Monroe, NP | Active | Admission weight: 65.8 kg. Trend fluid balance. |
| Neurologic | Neurologic checks every 2 hours during active correction | Urgent | Dr. Tessa Monroe, NP | Active | Assess orientation, level of consciousness, speech, pupils, strength, and new neurologic findings. |
| Safety | Seizure precautions | Urgent | Dr. Tessa Monroe, NP | Active | Suction and oxygen available; padded side rails per facility protocol. |
| Safety | Fall precautions and assisted ambulation only | Routine | Dr. Tessa Monroe, NP | Active | Recent fall, weakness, and altered mental status. |
| Dietary | Bedside swallow screen, then regular diet if passed; maintain ordered fluid restriction | Routine | Dr. Tessa Monroe, NP | Completed / Active | Swallow screen passed at 1100. Regular diet initiated. |
| Medication | Amlodipine 5 mg PO daily | Routine | Dr. Tessa Monroe, NP | Active | Indication: hypertension. Hold for SBP < 100 mmHg or symptomatic hypotension. |
| Medication | Acetaminophen 650 mg PO every 6 hours PRN mild pain or fever | Routine PRN | Dr. Tessa Monroe, NP | Active | Maximum total acetaminophen 3,000 mg per 24 hours. |
| Medication | Ondansetron 4 mg PO or IV every 8 hours PRN nausea | Routine PRN | Dr. Tessa Monroe, NP | Active | Indication: nausea associated with chemotherapy or hospitalization. |
| Medication | Enoxaparin 40 mg subcutaneous every 24 hours | Routine | Dr. Tessa Monroe, NP | Active | VTE prophylaxis. Hold for active bleeding, platelets < 50,000/mm³, or other contraindication. |
| Medication Reconciliation | Cisplatin / etoposide chemotherapy: no inpatient dose scheduled | Routine | Dr. Tessa Monroe, NP | On Hold | Oncology to determine timing of next treatment and sodium-monitoring strategy. |
| Laboratory | BMP, serum osmolality, urine osmolality, urine sodium, urine specific gravity | Urgent | Dr. Tessa Monroe, NP | Completed / Trending | Drawn in ED at 0845. Evaluate hypotonic hyponatremia and renal water handling. |
| Laboratory | CBC with differential | Routine | Dr. Tessa Monroe, NP | Completed | Assess blood counts following recent chemotherapy. |
| Laboratory | TSH and free T4 | Routine | Dr. Tessa Monroe, NP | Completed | Evaluate thyroid dysfunction as alternative cause of hyponatremia. |
| Laboratory | Serum cortisol | Routine | Dr. Tessa Monroe, NP | Completed | Evaluate adrenal insufficiency as alternative cause. |
| Laboratory | Serum uric acid | Routine | Dr. Tessa Monroe, NP | Completed | Additional supportive data in evaluation of SIADH. |
| Diagnostic | CT head without contrast | Urgent | Dr. Tessa Monroe, NP | Completed | Completed in ED at 0930, before hypertonic saline. No acute intracranial abnormality. |
| Consult | Endocrinology consultation | Urgent | Dr. Tessa Monroe, NP | Completed | Evaluated at 1130. SIADH management and sodium correction recommendations. |
| Consult | Oncology consultation | Routine | Dr. Tessa Monroe, NP | Requested | Review small cell lung cancer and future chemotherapy plan. |
| Vital Sign | 1000 | 1400 | Reference Range |
|---|---|---|---|
| Temperature | 36.8°C / 98.2°F | 36.7°C / 98.1°F | 36.1–37.2°C / 97–99°F |
| Heart Rate | 82 bpm | 80 bpm | 60–100 bpm |
| Respiratory Rate | 18 breaths/min | 16 breaths/min | 12–20 breaths/min |
| Blood Pressure | 132/78 mmHg | 130/76 mmHg | <120/<80 mmHg |
| Oxygen Saturation | 96% | 97% | 95–100% |
| Pain | 0/10 | 0/10 | Subjective scale 0–10 |
| Orientation | Oriented to person only | Oriented to person only; more attentive | Alert and appropriately oriented |
| Urine Output | Strict I&O initiated | 150 mL / 4 hr (1000–1400) | ≥ 0.5 mL/kg/hr |
| Weight | 65.8 kg (admission) | — | Trend daily |
| Lab Test | 0845 Result | Reference Range |
|---|---|---|
| Sodium | 118 mEq/L | 135–145 mEq/L |
| Potassium | 3.8 mEq/L | 3.5–5.0 mEq/L |
| Chloride | 88 mEq/L | 95–105 mEq/L |
| CO₂ | 26 mEq/L | 22–28 mEq/L |
| BUN | 12 mg/dL | 10–20 mg/dL |
| Creatinine | 0.8 mg/dL | 0.6–1.2 mg/dL |
| Glucose | 98 mg/dL | 60–100 mg/dL |
| Serum Osmolality | 245 mOsm/kg | 285–295 mOsm/kg |
| Urine Osmolality | 450 mOsm/kg | 300–900 mOsm/kg |
| Urine Sodium | 65 mEq/L | 20–40 mEq/L |
| Urine Specific Gravity | 1.025 | 1.005–1.030 |
| Uric Acid | 2.8 mg/dL | 3.0–7.0 mg/dL |
| TSH | 2.1 mIU/L | 0.4–4.0 mIU/L |
| Free T4 | 1.1 ng/dL | 0.8–1.8 ng/dL |
| Cortisol | 15 mcg/dL | 6–23 mcg/dL |
| WBC | 3.4 ×10³/mcL | 5.0–11.0 ×10³/mcL |
| ANC | 1.5 ×10³/mcL | 1.5–8.0 ×10³/mcL |
| Hemoglobin | 10.8 g/dL | Female: 12–15 g/dL |
| Platelets | 142,000/mm³ | 150,000–450,000/mm³ |
- CT Head Without Contrast — Completed (ED, 0930): No acute intracranial hemorrhage, mass effect, or other acute intracranial abnormality identified. Completed before hypertonic saline was started.
- Serial Serum Sodium — Ongoing: 118 mEq/L at 0845; 120 mEq/L at 1200 after the 3% sodium chloride bolus. Rechecks continue every 2 hours during active correction.
- Serum Osmolality — Completed: 245 mOsm/kg.
- Urine Osmolality — Completed: 450 mOsm/kg.
- Urine Sodium — Completed: 65 mEq/L.
- Urine Specific Gravity — Completed: 1.025.
- Thyroid Evaluation — Completed: TSH 2.1 mIU/L and free T4 1.1 ng/dL.
- Adrenal Evaluation — Completed: Serum cortisol 15 mcg/dL.
- Bedside Swallow Screen — Completed (1100): Passed without signs of aspiration. Regular diet initiated.
- Endocrinology Consultation — Completed (1130): Clinical and laboratory pattern supports SIADH. Hypertonic saline, controlled sodium correction, fluid restriction, strict I&O, and close neurologic monitoring recommended.
- Oncology Consultation — Requested: Evaluation requested regarding small cell lung cancer as the likely cause of SIADH and planning for future chemotherapy cycles.
- 0815 — Patient arrived in the Emergency Department with her son for confusion, weakness, and a fall at home.
- 0845 — Serum and urine laboratory studies drawn.
- 0930 — CT head completed in the Emergency Department with no acute intracranial findings.
- 0945 — Sodium resulted at 118 mEq/L; Step-Down admission requested.
- 1000 — Patient admitted to Step-Down Unit, Room 412. Assessment shows clinical euvolemia with no focal neurologic deficit.
- 1000 — Seizure and fall precautions initiated. Admission weight 65.8 kg. Strict I&O started.
- 1015 — 3% sodium chloride 150 mL IV started over 20 minutes.
- 1035 — 3% sodium chloride infusion completed without complication.
- Sodium monitoring and neurologic assessments increased to every 2 hours during active correction.
- 1100 — Bedside swallow screen passed. Regular diet initiated with 800 mL/day fluid restriction.
- 1130 — Endocrinology evaluation completed.
- 1200 — Repeat sodium 120 mEq/L (+2 mEq/L). Provider notified.
- 1400 — First four hours of I&O: 240 mL oral intake and 150 mL concentrated urine output.
- Oncology consultation requested regarding likely paraneoplastic SIADH.
Review Eleanor's neurologic findings, serum and urine studies, current treatment, and safety precautions before answering.
Eleanor has significant hyponatremia with a sodium of 118 mEq/L and a low serum osmolality of 245 mOsm/kg, confirming hypotonic hyponatremia. Despite the diluted serum, her urine remains concentrated at 450 mOsm/kg with a urine specific gravity of 1.025 and urine sodium of 65 mEq/L. Her low urine output of 150 mL over four hours also reflects ongoing water retention.
In SIADH, ADH continues to promote renal water reabsorption even when the serum is already hypotonic. Water retention dilutes the serum sodium while the kidneys continue producing relatively concentrated urine. Low serum uric acid provides an additional clue that supports the SIADH pattern.
Eleanor is clinically euvolemic, which is important. Hypovolemic hyponatremia would generally be associated with findings of volume depletion, while hypervolemic hyponatremia may occur with conditions such as heart failure and is associated with evidence of excess extracellular fluid. Her small cell lung cancer further supports SIADH because this malignancy can produce inappropriate ADH activity.
Eleanor's sodium is 118 mEq/L and she already has neurologic manifestations including confusion, weakness, and a fall. The immediate priority is therefore controlled treatment of symptomatic hyponatremia rather than relying on fluid restriction alone. The ordered 3% sodium chloride provides a small, controlled increase in serum sodium with the goal of improving neurologic symptoms. Her sodium rose from 118 to 120 mEq/L after the bolus, which is the modest early rise the team intended.
The nurse should monitor serum sodium every 2 hours during active correction and perform frequent neurologic assessments. A modest early increase is desired; the goal is not to rapidly return the sodium to the normal range. For Eleanor, the care team is using a conservative limit of no more than 8 mEq/L during a 24-hour period.
Correcting chronic or potentially chronic hyponatremia too quickly can cause osmotic demyelination syndrome, which may produce dysarthria, dysphagia, weakness, altered mental status, spasticity, or other severe neurologic injury. If the sodium begins rising faster than intended, active sodium correction should be stopped and the provider notified. D5W and/or desmopressin may be ordered to slow or reverse overcorrection.
Seizure precautions, fall precautions, strict intake and output, daily weights, and monitoring for a sudden increase in dilute urine output are also important. Once the acute neurologic risk is controlled, fluid restriction becomes a key part of managing the underlying SIADH.
Eleanor demonstrates gradual neurologic improvement after initial 3% hypertonic saline followed by fluid restriction and close electrolyte monitoring. Serum sodium has increased from 118 to 124 mEq/L over 24 hours without evidence of overcorrection, seizure activity, or new neurologic deficit.
Chief Concern
Follow-up of symptomatic hypotonic hyponatremia secondary to SIADH following initial treatment with hypertonic saline.
Interval History
Eleanor received one 150 mL bolus of 3% sodium chloride yesterday for symptomatic hyponatremia with confusion, weakness, and recent fall.
Following the initial hypertonic saline bolus, serum sodium increased gradually and neurologic symptoms began to improve. No additional hypertonic saline bolus was required.
Serial sodium values during the first 24 hours were 118 mEq/L at presentation, 120 mEq/L after initial treatment, 121 mEq/L later in the afternoon, 122 mEq/L in the evening, 123 mEq/L overnight, and 124 mEq/L at the current assessment.
Total sodium increase has therefore been 6 mEq/L over approximately 24 hours. This remains within the ordered correction ceiling of no more than 8 mEq/L during the first 24-hour period.
Mental status has improved from orientation to person only to orientation to person and place. Patient continues to have intermittent difficulty identifying the correct date but follows commands consistently and participates appropriately in conversation.
No seizure activity, dysarthria, dysphagia, new weakness, spasticity, decreased level of consciousness, or other findings concerning for osmotic demyelination have been observed.
Past Medical History
- Small cell lung cancer on active treatment
- Hypertension
- Osteoarthritis
- Former smoker
- Sulfa drug allergy — rash
Family History
- No known familial endocrine disorder
- No known family history of chronic hyponatremia
Social History
- Former cigarette smoker
- Stopped smoking approximately 3 months ago
- Son remains actively involved in care and discharge planning
- No reported recent excessive alcohol use
Review of Systems
Constitutional: Generalized weakness improving.
Neurologic: More alert. Oriented to person and place. Intermittently confused regarding date. Denies headache. No seizure activity, new focal weakness, difficulty speaking, or difficulty swallowing.
Cardiovascular: Denies chest pain, palpitations, or syncope.
Respiratory: Denies acute shortness of breath.
Gastrointestinal: Intermittent mild nausea. No vomiting or diarrhea. Tolerating oral diet.
Musculoskeletal: Weakness improved. Tolerated assisted transfer to chair.
Physical Examination
General: Awake, more alert, and interactive. No acute distress.
Cardiovascular: Regular rate and rhythm. Normal S1 and S2.
Respiratory: Respirations even and nonlabored. Lungs clear to auscultation bilaterally.
Neurologic: Alert and oriented to person and place. Speech clear. Follows commands appropriately. Strength improved and symmetric. No focal neurologic deficit. No dysarthria, dysphagia, or abnormal muscle tone noted.
Volume Status: Clinically euvolemic without peripheral edema, jugular venous distention, or signs of dehydration.
Intake / Output
Total documented oral fluid intake over the previous 24 hours is 760 mL. Total urine output is 825 mL. Urine remains concentrated.
Morning weight is 65.4 kg compared with admission weight of 65.8 kg.
Labs
Sodium has increased from 118 mEq/L to 124 mEq/L over approximately 24 hours. Potassium is 3.9 mEq/L, chloride 92 mEq/L, CO₂ 25 mEq/L, BUN 14 mg/dL, creatinine 0.9 mg/dL, and glucose 94 mg/dL.
Serum osmolality has increased from 245 to 258 mOsm/kg. Repeat urine osmolality remains concentrated at 410 mOsm/kg. Urine sodium is 58 mEq/L and urine specific gravity is 1.020.
Diagnostics
Previous CT head showed no acute intracranial abnormality. Serial neurologic assessments demonstrate improving mentation without new focal findings.
Assessment
SIADH with improving symptomatic hypotonic hyponatremia following initial hypertonic saline and ongoing fluid restriction.
Sodium has corrected by 6 mEq/L during the first 24 hours, remaining within the ordered conservative correction limit.
Altered mental status is improving. No evidence of seizure activity or osmotic demyelination syndrome.
Small cell lung cancer remains the likely underlying cause of inappropriate ADH secretion.
Plan
- No additional hypertonic saline at this time because neurologic symptoms are improving.
- Continue fluid restriction at 800 mL per 24 hours.
- Continue strict intake and output.
- Continue daily morning weights.
- Space serum sodium monitoring to every 4 hours now that active hypertonic saline therapy has ended and correction remains controlled.
- Continue BMP monitoring.
- CBC with differential and serum uric acid with morning labs.
- Maintain total sodium correction within prescribed limits.
- If sodium begins to rise unexpectedly or exceeds correction parameters, notify provider immediately and consider desmopressin and/or D5W for controlled re-lowering.
- Continue neurologic assessments every 4 hours.
- Continue seizure precautions.
- Continue fall precautions.
- Activity up with assistance as tolerated.
- Physical therapy evaluation.
- Continue Endocrinology follow-up.
- Oncology consultation for management of underlying small cell lung cancer and sodium monitoring during future chemotherapy cycles.
Provider Information
Dr. Tessa Monroe, NP
Critical Care • Step-Down Service
Patient demonstrates improved mental status compared with admission. Patient is awake and oriented to person and place but remains intermittently confused regarding date. She follows commands consistently and participates appropriately in conversation.
No seizure activity, dysarthria, dysphagia, abnormal muscle tone, new weakness, or other acute neurologic change noted during shift. Neuro checks continue as ordered.
Serum sodium is currently 124 mEq/L, increased from 118 mEq/L at presentation. Total correction over approximately 24 hours is 6 mEq/L. Provider aware of current trend.
Fluid restriction of 800 mL per 24 hours maintained. Total documented oral fluid intake for the previous 24 hours is 760 mL. Patient verbalizes understanding that beverages and liquid foods must be included in the daily total.
Total urine output for the previous 24 hours is 825 mL. Urine remains yellow and concentrated in appearance. No sudden increase in urine output observed.
Morning weight is 65.4 kg compared with admission weight of 65.8 kg.
Patient assisted to chair this morning with minimal assistance and tolerated activity without dizziness, acute weakness, or change in mental status.
Fall and seizure precautions remain active. Bed alarm in use. Non-slip footwear applied. Call light within reach.
20-gauge right forearm and 22-gauge left forearm IV sites remain patent, clean, dry, and intact.
Son remains at bedside and participates in fluid-restriction education. Patient and son instructed to report worsening confusion, headache, nausea, weakness, difficulty speaking, difficulty swallowing, or seizure activity immediately.
Endocrinology
Dr. Fatima Almasi, NP
Endocrinology
Sodium has increased from 118 to 124 mEq/L over approximately 24 hours following one hypertonic saline bolus and subsequent fluid restriction. Current correction remains within the established 8 mEq/L per 24-hour ceiling.
Patient's improving mental status supports adequate response to therapy. No additional hypertonic saline is indicated while symptoms continue improving and serum sodium is correcting appropriately.
Continue 800 mL/day fluid restriction, daily weights, strict intake and output, and serum sodium monitoring.
If sodium correction accelerates unexpectedly, notify Endocrinology immediately. D5W and/or desmopressin may be used if controlled re-lowering becomes necessary.
Oncology
Small cell lung cancer remains the likely underlying cause of paraneoplastic SIADH. Definitive management requires treatment of the malignancy.
Chemotherapy will continue under Oncology guidance once the patient is clinically stable. Sodium should be monitored closely before and after future treatment cycles.
Particular attention should be given to cisplatin-associated fluid administration requirements and post-treatment nausea, because both may complicate fluid management in a patient with recurrent SIADH.
Physical Therapy
Evaluation requested due to recent fall, weakness, and deconditioning. Patient currently tolerates transfer to chair with minimal assistance.
| Order Type | Order Details | Priority | Ordered By | Status | Comments |
|---|---|---|---|---|---|
| Medication | Sodium chloride 3%, 150 mL IV over 20 minutes once | Stat | Dr. Tessa Monroe, NP | Completed | Initial treatment for symptomatic severe hyponatremia. No repeat dose currently indicated. |
| Fluid Restriction | Restrict total oral fluid intake to 800 mL per 24 hours | Routine | Dr. Tessa Monroe, NP | Active | Include beverages, ice, gelatin, soup, and other liquid foods. |
| Nursing | Strict intake and output | Routine | Dr. Tessa Monroe, NP | Active | Previous 24 hr: intake 760 mL, urine output 825 mL. Report sudden water diuresis. |
| Nursing | Daily morning weight using same scale | Routine | Dr. Tessa Monroe, NP | Active | Admission 65.8 kg; current 65.4 kg. |
| Laboratory | Serum sodium every 4 hours | Urgent | Dr. Tessa Monroe, NP | Active | Active hypertonic therapy complete. Continue close monitoring of correction rate. |
| Laboratory | Basic metabolic panel every 6 hours | Routine | Dr. Tessa Monroe, NP | Active | Monitor sodium, potassium, chloride, renal function, and glucose. |
| Laboratory | Serum osmolality daily | Routine | Dr. Tessa Monroe, NP | Active | Trend response to SIADH treatment. |
| Laboratory | Repeat urine osmolality, urine sodium, and urine specific gravity daily | Routine | Dr. Tessa Monroe, NP | Active | Continue assessment of renal water handling. |
| Laboratory | CBC with differential daily with morning labs | Routine | Dr. Tessa Monroe, NP | Active | Trend WBC, ANC, hemoglobin, and platelets following recent chemotherapy and while on enoxaparin. |
| Laboratory | Serum uric acid daily with morning labs | Routine | Dr. Tessa Monroe, NP | Active | Trend supporting marker of SIADH during treatment. |
| Neurologic | Neurologic assessment every 4 hours | Urgent | Dr. Tessa Monroe, NP | Active | Monitor orientation, speech, swallowing, strength, muscle tone, and level of consciousness. |
| Safety | Seizure precautions | Urgent | Dr. Tessa Monroe, NP | Active | Continue while significant hyponatremia persists. |
| Safety | Fall precautions | Routine | Dr. Tessa Monroe, NP | Active | Continue due to residual confusion and recent fall. |
| Activity | Up with assistance as tolerated | Routine | Dr. Tessa Monroe, NP | Active | Assess for weakness, dizziness, and gait instability. |
| Dietary | Regular diet with 800 mL/day fluid restriction | Routine | Dr. Tessa Monroe, NP | Active | Count liquid foods toward total daily allowance. |
| Medication | Amlodipine 5 mg PO daily | Routine | Dr. Tessa Monroe, NP | Active | Hypertension. Hold for SBP <100 mmHg or symptomatic hypotension. |
| Medication | Acetaminophen 650 mg PO every 6 hours PRN mild pain or fever | Routine PRN | Dr. Tessa Monroe, NP | Active | Maximum total acetaminophen 3,000 mg per 24 hours. |
| Medication | Ondansetron 4 mg PO or IV every 8 hours PRN nausea | Routine PRN | Dr. Tessa Monroe, NP | Active | Treat nausea and limit additional non-osmotic ADH stimulation. |
| Medication | Enoxaparin 40 mg subcutaneous every 24 hours | Routine | Dr. Tessa Monroe, NP | Active | VTE prophylaxis. Hold for active bleeding or platelets <50,000/mm³. |
| Medication / Rescue | D5W and/or desmopressin if sodium correction exceeds prescribed limit | Stat PRN | Dr. Tessa Monroe, NP | Conditional | Notify provider and Endocrinology before administration. |
| Medication Reconciliation | Cisplatin / etoposide chemotherapy | Routine | Dr. Tessa Monroe, NP | On Hold Inpatient | Per Oncology recommendation: resume future cycles under Oncology guidance with sodium surveillance and coordinated hydration planning. |
| Consult | Endocrinology follow-up | Routine | Dr. Tessa Monroe, NP | Active | Continue management of SIADH and correction parameters. |
| Consult | Oncology consultation | Routine | Dr. Tessa Monroe, NP | Completed | Continue treatment of underlying small cell lung cancer with close sodium monitoring around future cycles. |
| Consult | Physical therapy evaluation | Routine | Dr. Tessa Monroe, NP | Requested | Evaluate weakness, gait, and fall risk. |
| Vital Sign | 1000 (12/31) | 1000 (1/1) | Reference Range |
|---|---|---|---|
| Temperature | 36.8°C / 98.2°F | 36.7°C / 98.1°F | 36.1–37.2°C / 97–99°F |
| Heart Rate | 82 bpm | 78 bpm | 60–100 bpm |
| Respiratory Rate | 18 breaths/min | 16 breaths/min | 12–20 breaths/min |
| Blood Pressure | 132/78 mmHg | 128/74 mmHg | <120/<80 mmHg |
| Oxygen Saturation | 96% | 97% | 95–100% |
| Pain | 0/10 | 0/10 | Subjective scale 0–10 |
| Orientation | Oriented to person only | Oriented to person and place | Alert and appropriately oriented |
| Urine Output | 150 mL / first 4 hr | 825 mL / previous 24 hr | ≥0.5 mL/kg/hr |
| Weight | 65.8 kg | 65.4 kg | Trend daily |
| Lab Test | 0845 (12/31) | 1000 (1/1) | Reference Range |
|---|---|---|---|
| Sodium | 118 mEq/L | 124 mEq/L | 135–145 mEq/L |
| Potassium | 3.8 mEq/L | 3.9 mEq/L | 3.5–5.0 mEq/L |
| Chloride | 88 mEq/L | 92 mEq/L | 95–105 mEq/L |
| CO₂ | 26 mEq/L | 25 mEq/L | 22–28 mEq/L |
| BUN | 12 mg/dL | 14 mg/dL | 10–20 mg/dL |
| Creatinine | 0.8 mg/dL | 0.9 mg/dL | 0.6–1.2 mg/dL |
| Glucose | 98 mg/dL | 94 mg/dL | 60–100 mg/dL |
| Serum Osmolality | 245 mOsm/kg | 258 mOsm/kg | 285–295 mOsm/kg |
| Urine Osmolality | 450 mOsm/kg | 410 mOsm/kg | 300–900 mOsm/kg |
| Urine Sodium | 65 mEq/L | 58 mEq/L | 20–40 mEq/L |
| Urine Specific Gravity | 1.025 | 1.020 | 1.005–1.030 |
| Uric Acid | 2.8 mg/dL | 3.0 mg/dL | 3.0–7.0 mg/dL |
| WBC | 3.4 ×10³/mcL | 3.6 ×10³/mcL | 5.0–11.0 ×10³/mcL |
| ANC | 1.5 ×10³/mcL | 1.6 ×10³/mcL | 1.5–8.0 ×10³/mcL |
| Hemoglobin | 10.8 g/dL | 10.6 g/dL | Female: 12–15 g/dL |
| Platelets | 142,000/mm³ | 148,000/mm³ | 150,000–450,000/mm³ |
- Serial Serum Sodium — Ongoing: Sodium trend during the first 24 hours: 118 → 120 → 121 → 122 → 123 → 124 mEq/L. Total correction: 6 mEq/L.
- Serum Osmolality — Repeat: Increased from 245 to 258 mOsm/kg.
- Urine Osmolality — Repeat: 410 mOsm/kg compared with 450 mOsm/kg on admission.
- Urine Sodium — Repeat: 58 mEq/L compared with 65 mEq/L on admission.
- Urine Specific Gravity — Repeat: 1.020 compared with 1.025 on admission.
- CBC With Differential — Repeat: WBC 3.6 ×10³/mcL, ANC 1.6 ×10³/mcL, hemoglobin 10.6 g/dL, and platelets 148,000/mm³. Counts stable to slightly improved after recent chemotherapy.
- Serum Uric Acid — Repeat: 3.0 mg/dL compared with 2.8 mg/dL on admission.
- Neurologic Assessments — Ongoing: Orientation improved from person only to person and place. No seizure activity, dysarthria, dysphagia, new weakness, or other acute neurologic deficit observed.
- CT Head Without Contrast — Previously Completed: No acute intracranial abnormality.
- Endocrinology Follow-Up — Completed: Current sodium correction remains within prescribed parameters. No additional hypertonic saline currently recommended.
- Oncology Consultation — Completed: Small cell lung cancer considered the likely underlying cause of SIADH. Continued cancer treatment is planned with closer sodium surveillance around future chemotherapy cycles.
- Physical Therapy Evaluation — Requested: Evaluation pending for weakness, recent fall, and mobility progression.
- Initial 3% sodium chloride bolus completed without complication.
- Sodium increased gradually from 118 to 124 mEq/L over approximately 24 hours.
- Total 24-hour sodium correction: 6 mEq/L.
- No additional hypertonic saline required.
- Mental status improved from orientation to person only to orientation to person and place.
- No seizure activity or findings concerning for osmotic demyelination observed.
- Fluid restriction maintained at 800 mL per 24 hours.
- Previous 24-hour intake: 760 mL.
- Previous 24-hour urine output: 825 mL.
- Morning weight decreased from 65.8 kg to 65.4 kg.
- 0900 — Patient assisted to chair and tolerated activity with minimal assistance.
- Oncology consultation completed with plan to continue treatment of underlying small cell lung cancer while coordinating sodium surveillance.
- Patient and son received continued education regarding fluid restriction and neurologic symptoms to report.
Review Eleanor's sodium trend, neurologic response, urine output, and current correction parameters before answering.
Eleanor's sodium increased from 118 mEq/L to 124 mEq/L during the first 24 hours. The total correction is therefore 124 − 118 = 6 mEq/L over approximately 24 hours.
Her care plan limits correction to no more than 8 mEq/L during the first 24 hours, so the 6 mEq/L increase remains within the prescribed conservative range. Her improving orientation also indicates that treatment is relieving the neurologic manifestations of hyponatremia.
Monitoring cannot stop simply because she looks better. Sodium may continue rising after the initial treatment, particularly if the kidneys suddenly begin excreting large amounts of dilute urine. An unexpectedly rapid increase can place the patient at risk for osmotic demyelination syndrome even after the original hyponatremic symptoms begin improving.
For this reason, the nurse must continue trending serum sodium, urine output, neurologic findings, intake and output, and daily weight rather than attempting to normalize the sodium quickly.
A sudden increase in urine output may indicate that Eleanor has begun excreting a large amount of free water. When this occurs, serum sodium can rise unexpectedly quickly even if no additional hypertonic saline is being given. The nurse should compare the new sodium value with the previous value and calculate the total correction over the current 24-hour period.
If the sodium is rising faster than the prescribed limit, the nurse should notify the provider and Endocrinology immediately and ensure that active sodium-raising therapy is stopped. Frequent neurologic assessment should continue because excessive correction increases the risk of osmotic demyelination syndrome.
The nurse should anticipate that the provider may order desmopressin to slow free-water excretion and/or D5W to replace free water and carefully re-lower the serum sodium. These interventions are used under close monitoring because the objective is to return the correction trajectory to a safer range, not to recreate severe hyponatremia.
Continued strict intake and output is therefore clinically important rather than simply a documentation task. A change in urine volume can provide an early warning that the sodium trajectory may also be changing.
Eleanor is now alert and appropriately oriented after controlled correction of symptomatic hyponatremia. Sodium has progressed from 118 to 124 to 132 mEq/L without evidence of overcorrection, and the focus now shifts toward long-term SIADH management, cancer treatment, recurrence prevention, and discharge readiness.
Chief Concern
Follow-up of SIADH with improving hyponatremia after symptomatic presentation requiring initial hypertonic saline therapy.
Interval History
Eleanor continues to demonstrate clinical improvement following initial treatment with 3% sodium chloride and subsequent fluid restriction.
Serum sodium increased from 118 mEq/L on admission to 124 mEq/L during the first 24 hours, then to 128 mEq/L on 01/02 and 132 mEq/L today. This represents increases of 6, 4, and 4 mEq/L across the three 24-hour intervals, none exceeding the prescribed correction limit.
Current sodium is 132 mEq/L. Patient is awake, alert, and appropriately oriented. Her prior confusion has resolved, and she denies headache, dizziness, weakness, difficulty speaking, difficulty swallowing, or seizure activity.
She is tolerating a regular diet while maintaining the prescribed fluid restriction and is now ambulating independently with a steady gait.
Endocrinology and Oncology have reviewed long-term management. Because sodium continues to improve with fluid restriction alone, additional chronic pharmacologic therapy for SIADH is not being initiated at this time.
Past Medical History
- Small cell lung cancer on active treatment
- SIADH associated with small cell lung cancer
- Hypertension
- Osteoarthritis
- Former smoker
- Sulfa drug allergy — rash
Family History
- No known familial endocrine disorder
- No known family history of chronic hyponatremia
Social History
- Former cigarette smoker
- Quit approximately 3 months ago after lung cancer diagnosis
- Son remains actively involved in care and discharge teaching
- No reported recent excessive alcohol use
Review of Systems
Constitutional: Reports improved energy and strength.
Neurologic: Denies confusion, headache, dizziness, seizure activity, weakness, dysarthria, or dysphagia.
Cardiovascular: Denies chest pain, palpitations, or syncope.
Respiratory: Denies acute shortness of breath.
Gastrointestinal: Tolerating oral intake. Denies vomiting or diarrhea. Intermittent chemotherapy-associated nausea remains controlled.
Musculoskeletal: Ambulating independently without recurrent weakness or instability.
Physical Examination
General: Awake, alert, comfortable, and in no acute distress.
Cardiovascular: Regular rate and rhythm. Normal S1 and S2.
Respiratory: Respirations even and nonlabored. Lungs clear to auscultation bilaterally.
Neurologic: Alert and oriented to person, place, and time. Speech clear. Strength equal bilaterally. No abnormal muscle tone, focal deficit, dysarthria, or dysphagia.
Mobility: Ambulates independently with steady gait.
Volume Status: Clinically euvolemic. No edema, jugular venous distention, or evidence of volume depletion.
Intake / Output
Previous 24-hour oral fluid intake: 780 mL. Previous 24-hour urine output: 1,050 mL.
Urine remains moderately concentrated without sudden high-volume water diuresis. Morning weight is 65.2 kg compared with 65.8 kg on admission and 65.4 kg at the 24-hour assessment.
Labs
Sodium is now 132 mEq/L compared with 128 mEq/L on 01/02, 124 mEq/L at 24 hours, and 118 mEq/L on admission.
Potassium is 4.0 mEq/L, chloride 98 mEq/L, CO₂ 25 mEq/L, BUN 16 mg/dL, creatinine 0.8 mg/dL, and glucose 96 mg/dL.
Serum osmolality has increased to 275 mOsm/kg. Urine osmolality is 360 mOsm/kg, urine sodium 48 mEq/L, and urine specific gravity 1.015.
CBC demonstrates WBC 4.0 ×10³/mcL, ANC 1.9 ×10³/mcL, hemoglobin 10.7 g/dL, and platelets 156,000/mm³.
Diagnostics
Serial neurologic examinations demonstrate return to baseline mentation without new neurologic deficits. Previous CT head remains without acute abnormality.
Assessment
SIADH associated with small cell lung cancer, with improving hypotonic hyponatremia after appropriate acute treatment and ongoing fluid restriction.
Neurologic manifestations have resolved. Sodium correction has remained controlled without documented overcorrection or evidence of osmotic demyelination syndrome.
Patient is approaching discharge readiness but remains at risk for recurrent SIADH while the underlying malignancy remains active.
Plan
- Continue 800 mL per 24-hour fluid restriction until outpatient reassessment.
- Continue regular diet.
- Continue strict intake and output while hospitalized.
- Continue daily morning weights while hospitalized.
- Repeat BMP prior to discharge.
- Continue neurologic assessments every 8 hours while hospitalized.
- Outpatient sodium monitoring to be coordinated with Oncology and primary care.
- No additional hypertonic saline indicated.
- No oral urea, salt-tablet therapy, or vasopressin-receptor antagonist initiated at this time because sodium continues to improve with fluid restriction.
- Reassess need for additional SIADH therapy if sodium fails to improve, declines again, or fluid restriction becomes ineffective or poorly tolerated.
- Advance activity as tolerated.
- Complete discharge teaching regarding fluid restriction, symptoms of recurrent hyponatremia, and fall prevention.
- Continue treatment of underlying small cell lung cancer under Oncology guidance.
- Coordinate sodium surveillance around future chemotherapy cycles.
- Coordinate cisplatin hydration requirements with SIADH fluid-management plan.
- Treat chemotherapy-associated nausea promptly because nausea can stimulate additional ADH release.
- Oncology follow-up within 1 week.
- Primary care follow-up within 2 weeks.
- Endocrinology follow-up as scheduled.
Provider Information
Dr. Tessa Monroe, NP
Critical Care • Step-Down Service
Patient awake, alert, and appropriately oriented. Patient participates appropriately in conversation and care decisions. No confusion noted during assessment.
Patient denies headache, dizziness, weakness, difficulty speaking, difficulty swallowing, or visual change. No seizure activity or new neurologic deficit observed.
Patient ambulating independently in room and hallway with steady gait. Physical therapy has cleared patient for independent mobility. No recurrent fall or near-fall reported.
Sodium currently 132 mEq/L. Patient and son informed that improvement does not eliminate the risk of recurrent hyponatremia while the underlying SIADH persists.
Fluid restriction of 800 mL per 24 hours maintained. Previous 24-hour oral intake totals 780 mL. Patient independently identifies beverages, ice, soup, gelatin, and liquid supplements as part of her daily fluid allowance.
Previous 24-hour urine output is 1,050 mL. No abrupt high-volume urine output noted. Morning weight is 65.2 kg.
20-gauge right forearm IV remains patent, clean, dry, and intact. Left forearm IV removed earlier today without complication as IV therapy is no longer routinely required.
Medication teaching completed for amlodipine, PRN ondansetron, and PRN acetaminophen. Patient understands that inpatient enoxaparin is for VTE prevention and will not continue after discharge unless separately prescribed.
Education provided regarding signs of recurrent hyponatremia including headache, nausea, increasing fatigue, weakness, difficulty concentrating, confusion, gait instability, and decreased responsiveness.
Patient instructed to seek urgent evaluation for severe confusion, seizure activity, marked weakness, or decreased level of consciousness.
Son remains present and participates in teaching. Patient and son correctly repeat the fluid limit, symptoms to report, follow-up plan, and importance of scheduled sodium monitoring.
Endocrinology
Dr. Fatima Almasi, NP
Endocrinology
Sodium continues to improve with fluid restriction after completion of acute hypertonic saline therapy. Current sodium is 132 mEq/L and neurologic symptoms have resolved.
No oral urea, salt tablets, or vasopressin-receptor antagonist will be started at this time because the patient is responding to current management.
Additional therapy should be reconsidered if recurrent hyponatremia develops or adequate sodium control cannot be maintained with fluid restriction.
Continue outpatient electrolyte surveillance and reassess fluid restriction as the malignancy responds to treatment.
Oncology
Small cell lung cancer remains the likely underlying driver of paraneoplastic SIADH. Treatment of the malignancy remains an important component of long-term SIADH control.
Plan is to continue cancer-directed therapy under Oncology supervision rather than stop chemotherapy solely because SIADH occurred.
Serum sodium should be obtained before subsequent chemotherapy cycles and monitored afterward based on symptoms and treatment plan. Cisplatin-associated hydration protocols will be coordinated carefully with the patient's fluid restriction.
Chemotherapy-associated nausea should also be treated promptly because nausea and physiologic stress can stimulate ADH release and worsen hyponatremia.
Physical Therapy
Patient demonstrates independent bed mobility, transfers, and hallway ambulation with steady gait. No assistive device required at this time. Cleared for discharge from a physical therapy standpoint.
| Order Type | Order Details | Priority | Ordered By | Status | Comments |
|---|---|---|---|---|---|
| Medication | Sodium chloride 3%, 150 mL IV over 20 minutes once | Stat | Dr. Tessa Monroe, NP | Completed | Acute symptomatic hyponatremia resolved. No additional dose indicated. |
| Fluid Restriction | Restrict total fluid intake to 800 mL per 24 hours | Routine | Dr. Tessa Monroe, NP | Active | Continue through discharge until reassessed by treating team. |
| Nursing | Strict intake and output | Routine | Dr. Tessa Monroe, NP | Active | Previous 24 hr intake: 780 mL. Urine output: 1,050 mL. |
| Nursing | Daily morning weight using same scale | Routine | Dr. Tessa Monroe, NP | Active | 65.8 kg → 65.4 kg → 65.2 kg. |
| Neurologic | Neurologic assessment every 8 hours | Routine | Dr. Tessa Monroe, NP | Active | Decreased from every 4 hours. Neurologic status at baseline. Report any new confusion, dysarthria, dysphagia, or weakness. |
| Laboratory | Basic metabolic panel prior to discharge | Routine | Dr. Tessa Monroe, NP | Scheduled | Confirm sodium remains on controlled trajectory before discharge. |
| Laboratory | Serum osmolality daily while hospitalized | Routine | Dr. Tessa Monroe, NP | Active | Current result 275 mOsm/kg. |
| Laboratory | Urine osmolality, urine sodium, and urine specific gravity | Routine | Dr. Tessa Monroe, NP | Completed | Current urine osmolality 360 mOsm/kg, urine sodium 48 mEq/L, specific gravity 1.015. |
| Laboratory | CBC with differential daily with morning labs | Routine | Dr. Tessa Monroe, NP | Active | Current WBC 4.0 ×10³/mcL, ANC 1.9 ×10³/mcL, platelets 156,000/mm³. |
| Laboratory | Serum uric acid daily with morning labs | Routine | Dr. Tessa Monroe, NP | Active | Current result 3.4 mg/dL. |
| Safety | Fall precautions | Routine | Dr. Tessa Monroe, NP | Active Until Discharge | Continue because admission included confusion, weakness, and a fall. |
| Safety | Seizure precautions | Routine | Dr. Tessa Monroe, NP | Discontinued | Neurologic status normalized and sodium substantially improved. |
| Activity | Activity as tolerated | Routine | Dr. Tessa Monroe, NP | Active | Independent ambulation. Physical therapy cleared. |
| Dietary | Regular diet with 800 mL/day fluid restriction | Routine | Dr. Tessa Monroe, NP | Active | Patient independently tracks fluid allowance. |
| Medication | Amlodipine 5 mg PO daily | Routine | Dr. Tessa Monroe, NP | Active | Hypertension. Hold for SBP <100 mmHg or symptomatic hypotension. |
| Medication | Acetaminophen 650 mg PO every 6 hours PRN mild pain or fever | Routine PRN | Dr. Tessa Monroe, NP | Active | Maximum total dose 3,000 mg per 24 hours. |
| Medication | Ondansetron 4 mg PO every 8 hours PRN nausea | Routine PRN | Dr. Tessa Monroe, NP | Active | Continue at discharge as needed for chemotherapy-associated nausea. |
| Medication | Enoxaparin 40 mg subcutaneous every 24 hours | Routine | Dr. Tessa Monroe, NP | Discontinue At Discharge | Inpatient VTE prophylaxis only. No current outpatient indication. |
| Medication | Oral urea / sodium chloride tablets / vasopressin-receptor antagonist | Routine | Dr. Fatima Almasi, NP | Not Started | Additional SIADH pharmacotherapy deferred because sodium continues to improve with fluid restriction. Reconsider if hyponatremia recurs. |
| Oncology | Continue cancer-directed therapy under Oncology supervision | Routine | Dr. Tessa Monroe, NP | Planned | Per Oncology recommendation: treat underlying small cell lung cancer. Coordinate hydration requirements and sodium monitoring around treatment cycles. |
| Consult | Endocrinology follow-up | Routine | Dr. Tessa Monroe, NP | Scheduled | Reassess SIADH management and need for additional therapy. |
| Consult | Physical therapy evaluation | Routine | Dr. Tessa Monroe, NP | Completed | Cleared for independent ambulation. |
| Discharge Planning | Complete discharge planning | Routine | Dr. Tessa Monroe, NP | In Progress | Confirm medications, fluid plan, laboratory monitoring, education, and follow-up. |
| Patient Education | SIADH and recurrent hyponatremia education | Routine | Dr. Tessa Monroe, NP | In Progress | Fluid tracking, symptom recognition, cancer-treatment coordination, and when to seek care. |
| Follow-Up | Oncology follow-up within 1 week | Routine | Dr. Tessa Monroe, NP | Scheduled | Continue cancer-directed therapy and coordinate sodium surveillance. |
| Follow-Up | Primary care follow-up within 2 weeks | Routine | Dr. Tessa Monroe, NP | Scheduled | Review electrolytes, blood pressure, medications, and recovery. |
| Vital Sign | 1000 (12/31) | 1000 (1/1) | 1000 (1/3) | Reference Range |
|---|---|---|---|---|
| Temperature | 36.8°C / 98.2°F | 36.7°C / 98.1°F | 36.6°C / 97.9°F | 36.1–37.2°C / 97–99°F |
| Heart Rate | 82 bpm | 78 bpm | 76 bpm | 60–100 bpm |
| Respiratory Rate | 18 breaths/min | 16 breaths/min | 16 breaths/min | 12–20 breaths/min |
| Blood Pressure | 132/78 mmHg | 128/74 mmHg | 126/72 mmHg | <120/<80 mmHg |
| Oxygen Saturation | 96% | 97% | 98% | 95–100% |
| Pain | 0/10 | 0/10 | 0/10 | Subjective scale 0–10 |
| Orientation | Oriented to person only | Oriented to person and place | Alert and oriented ×3 | Alert and appropriately oriented |
| Urine Output | 150 mL / first 4 hr | 825 mL / previous 24 hr | 1,050 mL / previous 24 hr | ≥0.5 mL/kg/hr |
| Weight | 65.8 kg | 65.4 kg | 65.2 kg | Trend daily |
| Lab Test | 0845 (12/31) | 1000 (1/1) | 1000 (1/3) | Reference Range |
|---|---|---|---|---|
| Sodium | 118 mEq/L | 124 mEq/L | 132 mEq/L | 135–145 mEq/L |
| Potassium | 3.8 mEq/L | 3.9 mEq/L | 4.0 mEq/L | 3.5–5.0 mEq/L |
| Chloride | 88 mEq/L | 92 mEq/L | 98 mEq/L | 95–105 mEq/L |
| CO₂ | 26 mEq/L | 25 mEq/L | 25 mEq/L | 22–28 mEq/L |
| BUN | 12 mg/dL | 14 mg/dL | 16 mg/dL | 10–20 mg/dL |
| Creatinine | 0.8 mg/dL | 0.9 mg/dL | 0.8 mg/dL | 0.6–1.2 mg/dL |
| Glucose | 98 mg/dL | 94 mg/dL | 96 mg/dL | 60–100 mg/dL |
| Serum Osmolality | 245 mOsm/kg | 258 mOsm/kg | 275 mOsm/kg | 285–295 mOsm/kg |
| Urine Osmolality | 450 mOsm/kg | 410 mOsm/kg | 360 mOsm/kg | 300–900 mOsm/kg |
| Urine Sodium | 65 mEq/L | 58 mEq/L | 48 mEq/L | 20–40 mEq/L |
| Urine Specific Gravity | 1.025 | 1.020 | 1.015 | 1.005–1.030 |
| Uric Acid | 2.8 mg/dL | 3.0 mg/dL | 3.4 mg/dL | 3.0–7.0 mg/dL |
| WBC | 3.4 ×10³/mcL | 3.6 ×10³/mcL | 4.0 ×10³/mcL | 5.0–11.0 ×10³/mcL |
| ANC | 1.5 ×10³/mcL | 1.6 ×10³/mcL | 1.9 ×10³/mcL | 1.5–8.0 ×10³/mcL |
| Hemoglobin | 10.8 g/dL | 10.6 g/dL | 10.7 g/dL | Female: 12–15 g/dL |
| Platelets | 142,000/mm³ | 148,000/mm³ | 156,000/mm³ | 150,000–450,000/mm³ |
- Serial Sodium Monitoring — Ongoing: Sodium progressed from 118 mEq/L on admission to 124 mEq/L at 24 hours, 128 mEq/L on 01/02, and 132 mEq/L at the current assessment. Changes of +6, +4, and +4 mEq/L per 24 hours; no 24-hour interval exceeded the prescribed correction ceiling.
- Serum Osmolality — Repeat: 245 → 258 → 275 mOsm/kg.
- Urine Osmolality — Repeat: 450 → 410 → 360 mOsm/kg.
- Urine Sodium — Repeat: 65 → 58 → 48 mEq/L.
- Urine Specific Gravity — Repeat: 1.025 → 1.020 → 1.015.
- CBC With Differential — Repeat: WBC 3.4 → 3.6 → 4.0 ×10³/mcL, ANC 1.5 → 1.6 → 1.9 ×10³/mcL, and platelets 142,000 → 148,000 → 156,000/mm³. Counts recovering after recent chemotherapy.
- Serum Uric Acid — Repeat: 2.8 → 3.0 → 3.4 mg/dL.
- Neurologic Assessments — Ongoing: Mental status has progressed from orientation to person only, to person and place, and now to appropriate orientation without focal neurologic deficit.
- CT Head Without Contrast — Previously Completed: No acute intracranial abnormality.
- Endocrinology Follow-Up — Completed: Additional chronic pharmacologic therapy deferred because sodium continues to improve with fluid restriction.
- Oncology Evaluation — Completed: Small cell lung cancer remains the likely cause of paraneoplastic SIADH. Cancer-directed therapy will continue with coordinated sodium monitoring and hydration planning.
- Physical Therapy — Completed: Patient cleared for independent ambulation.
- Sodium trend now 118 → 124 → 128 → 132 mEq/L.
- No documented sodium overcorrection during treatment.
- Patient now appropriately oriented without recurrent confusion.
- No seizure activity, dysarthria, dysphagia, new weakness, abnormal tone, or other findings concerning for osmotic demyelination.
- Previous 24-hour oral intake: 780 mL.
- Previous 24-hour urine output: 1,050 mL.
- Daily weight trend: 65.8 → 65.4 → 65.2 kg.
- 0900 — Physical therapy clearance received.
- Patient ambulating independently with steady gait.
- Endocrinology determined additional SIADH medication is not required at this time.
- Oncology confirmed plan to continue treatment of underlying small cell lung cancer with coordinated sodium surveillance.
- 1000 — Discharge planning initiated.
- 1100 — Patient and family teaching completed.
- 1200 — Outpatient follow-up arrangements confirmed.
Review Eleanor's complete course from symptomatic severe hyponatremia through controlled correction and discharge preparation before answering.
Eleanor should understand her prescribed fluid limit and how to measure it accurately. Water, coffee, tea, juice, ice, gelatin, soup, and liquid nutritional supplements all contribute to total daily fluid intake. She should not independently increase or decrease the restriction without discussing it with her healthcare team.
Eleanor and her son should recognize early symptoms of recurrent hyponatremia, including headache, nausea, unusual fatigue, weakness, difficulty concentrating, confusion, or gait instability. Severe confusion, seizure activity, marked weakness, or decreased responsiveness requires urgent medical evaluation.
Continued laboratory monitoring is important because treating the symptoms does not remove the underlying cause of SIADH. Her small cell lung cancer remains active, so sodium can fall again, particularly around illness, chemotherapy, nausea, or changes in fluid administration.
Eleanor should attend Oncology, primary care, and Endocrinology follow-up as scheduled and take prescribed medications correctly. She should also continue fall-prevention strategies until she is confident that weakness and confusion have completely resolved.
Oncology coordination is essential because Eleanor's small cell lung cancer is the likely source of inappropriate ADH secretion. Treating the underlying malignancy is therefore an important part of reducing recurrent paraneoplastic SIADH rather than simply treating each low sodium episode in isolation.
The nurse should confirm that Oncology has a plan for serum sodium monitoring before and after future treatment cycles and that any cisplatin hydration protocol is coordinated with Eleanor's fluid restriction. Chemotherapy-associated nausea should also be managed promptly because nausea can stimulate ADH release.
Endocrinology should reassess whether fluid restriction remains adequate. Eleanor is currently improving without additional chronic SIADH medication, but oral urea, increased solute therapy, or another treatment strategy may need to be reconsidered if sodium falls again or the fluid restriction becomes ineffective or poorly tolerated.
Primary care should help monitor electrolytes, blood pressure, medications, fluid-restriction adherence, and overall recovery. Before discharge, the nurse should verify that follow-up appointments, laboratory monitoring, medication reconciliation, written instructions, and family education are all complete.