Download - Case 1- M.H. (Chico State U., California)
Case 1- M.H. (Chico State U., California)
18M presents after 3 grand-mal seizures after collapsing during fraternity hazing ritual
Pledges were forced to do push-ups/exercises for hours in raw sewage that had leaked into basement of fraternity
Kept drinking from 5 gallon jug of water which was continuously refilled
Vomitted and urinated on themselves
Case 1
Initial vitals: 120/60 70 20 98% RA T=37.5 Clinically euvolemic Confused
Case 1
Initial labs Na = 110, urine Na <10, serum osmol = 270 How would you treat?
Hyponatremia
Sultana Qureshi, R2Lab RoundsFeb 8, 2007
Matthew Harrington
HypoNa Basics
HypoNa is a symptom of disease Na <135 mEq/L Most common lyte abn in hospital
pts Incidence 1%, increases with age Acute, symptomatic cases,
mortality up to 18%
Quick Physiology Review 3 fluid compartments
(2/3) ICF & (1/3)ECF (InterstitialF + IVF) Na concentration governs movement of
water across these spaces
Body tightly maintains serum osmolality within 1-2% of 275-295 mosmol/kg
Na balance = Renin-angiotensin Water balance = ADH
Quick Physiology Review
Hypotension or low ECF renin release from JGAangiotensin II aldosterone production Na reabsorption and K excretion
Incr serum osmolality, Decr. BP or volume ADH release from post. Pituitary More sens to hypovolemia than low
osmol.
Clinical Features
Absolute Na level not as important as RATE OF DECLINE
SymptomsSerum Na+ (mEq/L) Symptoms
135 - 130 Decreased taste
130 - 125 ThirstAnorexia, N + VMuscle cramps
125 - 120 WeaknessLethargy
RestlessnessConfusion
< 120 DeliriumComa
SeizuresThanks to Moritz!
Approach
Classify Osmolality and Volume status Osmolality
Hyperosmolar – excess solutes (ie glucose) draw water into ECF diluting Na
Iso-osmolar – psuedohyponatremia Hypo-osmolar (MOST COMMON) – excess
water in relation to Na stores (may be incr, decr or n) – categorized by volume status
Hypo-osmolar HypoNa Hypervolemic
CHF, ARF, CRF, cirrhosis/ascites, pregnancy Euvolemic
SIADH, adrenal insuff, hypothyroid, psychogenic polydipsia, sports
Hypovolemic Diuretics, diarrhea, sweating, third-spacing,
salt-wasting nephropathy
Causes of SIADH CNS disease
Brain tumor infarction injury abscess Meningitis/ Encephaliti
s
Pulmonary disease Pneumonia Tuberculosis Lung abscess Pulmonary
aspergillosis
Drugs
Exogenous vasopressin (enuresis)
Diuretics Chlorpropamide Vincristine Thioridazine Cyclophosphamide
Most common is hypo-osmolar hyponatremia
Case 2
75F – weak and dizzy x 1 week, falls at home presenting with hip #
PMHx – Hyperlipidemia, HTN, chronic diarrhea NYD
Meds: HCTZ, lipitor Vitals: 85, 110/70, 14, 95% RA
Case 2
Labs: Na- 112, K-4.5, Cl- 82, CO2 -12
Serum osmol – 240 Urine osmol – 300 Urine Na - <10 Cause of HypoNa? How would you treat?
Management
Guided by severity of symptoms and acuity
Chronic Gradual correction <0.5 mEq/L/hr
Acute/Symptomatic Tolerate faster correction up to 1-2
mEq/l/hr
Management CNS symptoms/seizures
Correct with hypertonic saline (3%) until resolved
usually need to increase Na by 4-6 mEq/L only Then correct 8-10mEq/L/day Formula
(Desired [Na+] – measured [Na+] ) x 0.6Wt(kg) = mEq Na+ req’d
Eg (117-112) X 0.6(70) = 210 mEq
Case 2 (continued) It’s July 1st and the Ortho R1 decides to
fluid resuscitate her with NS 2L bolus, then runs it at 200cc/hr
Pt admitted to Ortho Next morning, Na corrected to 136 Later that evening, pt develops
confusion, dysarthria, unable to move her arms and legs
What’s happening? Call stroke team?
Central Pontine Myelinolysis (CPM) Overaggressive correction of the serum sodium level
(usually >12 mEq/L/day)
Destruction of myelin in the pons (due to rapid changes in cell volume?)
Pts may develop confusion, cranial nerve palsies, spastic quadriplegia, or coma
More likely to occur in patients with chronic hyponatremia
Most cases reported in alcoholic, malnourished, and elderly patients
Can develop 1-3 days after rapid Na correction
Diagnosed by MRI
Supportive Management
Treatment (mild-mod symptoms) Hypovolemic hyponatremia
Correct with NS (0.9%) Euvolemic hyponatremia:
Restrict free water intake Treat underlying cause No NS in SIADH:
Worsens due to excessive water retention Lithium and demeclocycline
Hypervolemic hyponatremia: Restrict free water intake +/- diuretics (may increase Na loss)
Case 3 (Jan 12, 2007 – Sacremento, CA)
28F enters radio station competition “Hold your Wee for a Wii” Contestant who could drink the most water
without urinating won Possibly drank up to 2 gallons Nurse called into radio station during
competition stating danger Last heard from while driving home with
severe headache Found dead next morning
Questions?