1. Trauma & Surgical Critical Care
Fluids & Electrolytes
Scott G. Sagraves, MD, FACS
Assistant Professor
Trauma & Surgical Critical Care

2. The recognition and management of fluid, electrolyte, and related acid-base problems are common challenges on the surgical service.
Lawrence, Essentials of General Surgery

3. Goals Review concept of total body fluids Review types of crystalloids
Review electrolytes disturbances & their treatment strategies.

4. Body Fluids
16%
40% 4%
Body Water = 60% of a patient’s body weight

5. Why do you give D5½NS + 20 mEq/L KCl at 125 cc/hr to a patient?

6. Fluid Requirements typically 35 mL/kg/day
insensible loss = 700 mL/day or 0.2 cc/kg/day for every 1° C > 37°
kg = 100 mL/kg/day {4mL/kg/hr}
11-20 kg = 50 mL/kg/day {2mL/kg/hr}
> 21 kg = 20 mL/kg/day {1mL/kg/hr}
Trick for hourly maintenance = 40 + weight (kg)

7. Serum Values of Electrolytes
Cations Concentration, mEq/L
Sodium
Potassium
Calcium
Magnesium
Anions
Chloride CO
Phosphate

8. Daily Requirements for Electrolytes
Sodium: 1-2 mEq/kg/d
Potassium: mEq/kg/d
Calcium: mg/d
Magnesium: mg/d
Phosphorus: mg/d

9. IV Solutions Solution Na+ Cl- K+ Ca+2 HCO3- Glu
Plasma NS
D5W G LR
Serum Osmolality = [2 x Na] + [BUN/2.8] + [glucose/18]

10. Replacement Strategies
Sweat: D5¼NS + 5 mEq KCl/L
Gastric: D5½NS + 20 mEq KCl/L
Biliary/pancreatic: LR
Small Bowel: LR
Colon: LR
3rd space losses: LR

11. Resuscitation Crystalloids Replace blood loss at a 3:1 ratio
Initial bolus 1-2 liters, usually normal saline
If they have transient response, give additional fluids. Once 3-4 liters of crystalloid has been given consider blood.

12. INDICATORS OF SUCCESSFUL RESUSCITATION
PULSE bpm
URINARY OUTPUT
CHILDREN = 1.0 ml/kg/hr
ADULT = 0.5 ml/kg/hr
Clearance of lactate
Resolution of base deficit
BLOOD PRESSURE POOR INDICATOR

13. Fluid Status 140 GI loss 120 140 [Na] 160 low normal high ECV SIADH
Hypothyroid
Cortisol
GI loss
120
CHF
Cirrhosis
140
140
[Na]
GI Loss
Renal loss
Osmotic
NaHCO3
3% NaCl
Seawater
160 DI
Insensible
low
normal
high
ECV

14. Renal Regulatory Mechanisms
Aldosterone
distal tubules
sodium exchanged for K+ and H+
released by volume reduction
Antidiuretic Hormone (ADH)
increased tubular water reabsorption
posterior pituitary release

15. Acid/base 7.4 Respiratory Metabolic Acidosis Alkalosis BE = 0
HCO3 = 24
Metabolic
Acidosis
Respiratory
Alkalosis
7.4

16. ABG Rules
Rule 1: An increase or decrease in PaCO2 of 10 mm Hg, respectively, is associated with a reciprocal decrease or increase of 0.08 pH units.
Rule 2: An increase or decrease in [HCO3-] or 10 mEq/L respectively is associated with a directly related increase or decrease of 0.15 pH units.

17. Acidosis pH < 7.2 decreased responsiveness to catecholamines
cardiac dysfunction
arrhythmias
increased potassium serum levels

18. Case Studies

19. What do you think? What do you do?
“Found Down”
45 yo WM, found down, presumed to be assaulted, well known to ED for EtOH
CT head - hygromas, small ICH
labs:
Na = 118
K = 2.4
Cl = 74
What do you think? What do you do?

20. Severe Hyponatremia Correct sodium to above 120 mEq/dl
NaCl + 40 mEq/L KCl
3% Saline
furosemide diuresis (euvolemic)
serial electrolytes
be prepared to handle seizures
Replace potassium
Cl should correct itself

21. Hyponatremia 1% of hospitalized are hyponatremic
Neurologic conditions:
Seizures, coma, encephalopathy
Results from rapid  [Na]
Peripheral symptoms:
Cramping, twitches, fasciculations
Results from ion conduction aberrations

22. Hints… Na+ deficit (mEq) = (140 – Naserum) x 0.6 x Kg
Glucose increase 100 mg/dL or a BUN increase of 30 mg/dL  decrease of 1.5 – 2 mEq/L Sodium

23. Central Pontine Myelinosis
Results from overcorrection of sodium
Correction of > 25 mEq per hrs
Concurrent hypoxia
Presence of liver disease
Acute correction limit 25 mEq /day
Chronic correction limit 10 mEq/day

24. Treatment Strategies Hypovolemic Hyponatremia
expand intravascular volume
0.9% NS or 3% Hypertonic Saline
Hypervolemic Hyponatremia
water restriction
treat medical condition
hemodialysis
Euvolemic Hyponatremia
SIADH
restrict fluid: 7-10 ml/kg/d
demeclocycline antagonizes vasopressin

25. HDU Code A Code Blue is called in the HDU.
65 yo male with ESRD has “arrested” awaiting his dialysis treatment. CPR and BVM resuscitation are in progress and an IV has been established.
What do you think? What do you do?

26. Pre-Arrest Rhythm Strip

27. “Arrest” Strip

28. Diagnosis? HYPERKALEMIA
Treatment
CaCl2 10% - 1 ampule
Sodium Bicarbonate - 1 ampule
D50 & Insulin 10 U
2 - agonist nebulizer- cellular K 
Kayexalate®

29. Causes of Hyperkalemia
Renal dysfunction
Acidemia
Hypoaldosteronism
Drugs
Excessive intake
WBC > 100,000
Platelets > 600,000
Cell Death
Rhabdomyolysis
Tumor lysis
Burns
Hemolysis

30. Potassium Metabolism Normal daily intake 100 mEq
Renal filters & reabsorbs prox. Tubule
Potassium  1/[aldosterone]
Acidosis  [potassium] with H+ out
Alkalosis  [potassium] with H+ in

31. What do you think? What do you do?
Post op patient
42 year old female admitted to the ICU post op after undergoing a thyroidectomy for thyroid cancer.
She is complaining of peri-oral numbness and tingling. Her DTRs are hyperactive and her ECG has a prolonged QT interval.
What do you think? What do you do?

32. HYPOCALCEMIA Chvostek’s sign - facial muscle spasm
Trousseau’s sign - carpal spasm
Treatment
monitor ECG
IV calcium
follow up labs
oral calcium supplements
normal is 1 gram/day

33. What do you think? What do you do?
Blunt Trauma
23 year old male, s/p MVC with blunt abdominal and orthopedic trauma
HD#3 develops fever, N/V, abdominal pain, refractory hypotension, with oliguria.
Na+ 130, K- 5.5, Glu 65, pH 7.29
What do you think? What do you do?

34. ACUTE ADRENAL INSUFFICIENCY
Treatment
fluid and vasopressor support
treat precipitating conditions
draw baseline cortisol level
administer dexamethasone
ACTH stimulation test
hydrocortisone 100 mg IV q 8

35. Hydrocortisone Stimulation Test
Baseline cortisol
> 20 - no further therapy
test
< 15 empiric therapy
Administer Cortrosyn 250 g IV
Obtain levels 30 & 60 minutes post injection

36. You are called to the Bedside…
55 yo male, s/p fall with isolated, repaired fractured femur.
Pt’s LOC decreased and patient began to seize.
EKG showed…
What Do You Think? What Do You Do?

37. Hypomagnesemia
Mg plays role in energy metabolism, protein synthesis, cell division, & calcium regulation in muscle.
Definition < 1.6 mg/dL
Causes: poor diet, diuretics, gut losses, & massive diarrhea, resuscitation.

38. Mg Rx Replacement Magnesium Sulfate 1 gram = 8 mEq
Infuse at rate of 2 gram/hour
Emergency: 2 grams over 5 minutes

39. What do you think? What do you do?
Closed Head Injury
32 year old female, MVC, GCS -7, intubated, with CT scan showing SAH, cerebral edema. ICP monitor shows a pressure of 27. CPP 55.
Over the next several days, Na+ > 150.
What do you think? What do you do?

40. DIABETES INSIPIDUS Signs Treatment [Na+]  150
Urine specific gravity 1.007
polyuria, clear urine
dDAVP 1g sq raises urine osmolality in 2 hours
Treatment
free water deficit = (0.6) x (Kg) x ([Naserum/140] -1)
dDAVP 2g sq every 12 hours
for every L water deficit [Na+] will rise 3 mEq above 140

41. What do you think? What do you do?
The transfer
50 year old obese female, transferred for critical care management after a bowel resection. Presents with obtundation, hypotension, tachypnea, and emesis.
C/O abdominal pain and has fruity breath
amylase, lipase are elevated, Na+ 127
What do you think? What do you do?

42. Work up?
ABG
Electrolyte panel
urine analysis
CBC
Serum Ketones

43. Hyperglycemia Characteristic DKA NKHC Glucose 400-800 > 1000
Acidosis Severe min.
Ketones High low
Dehydration Mod. High
Na  1.6 for every 100  glucose above 200

44. Treatment Adequate fluid replacement narrowing of anion gap
crystalloids: LR, NS, ½ NS
Insulin
bolus units/kg
infusion 0.1 units/kg/hour
goal reduce plasma glucose mg/dL/hr
Electrolytes
K replacement mEq/hour after UOP OK
Mg, PO4 replacement

45. What do you think? What do you do?
The drunk
37 year old male, h/o EtOH abuse fell from a deer hunting tree stand. C5 fracture without cord involvement.
HD #2 develops delirium tremors moved from SIU to ICU. Librium started.
HD#4, dobhoff placed and tube feeds started. That night, the patient’s respiratory status worsens and he is intubated.
What do you think? What do you do?

46. HYPOPHOSPHATEMIA “Refeeding Syndrome” Hypophosphatemia malnutrition
alcoholism
Hypophosphatemia
limits oxygen unloading
immunocompromise
muscle weakness  failure to wean

47. Treatment IV supplementation in emergent cases
sodium or potassium phosphorous
PO supplementation routinely
Keep (phosphorous x calcium) ratio < 60
Magnesium should be replenished simultaneously

48. The burn patient
25 year male, caught fire after his lawnmower exploded as he was filling it with gasoline while smoking a cigarette.
The patient sustained second and third degree burns estimated at 40 % total body surface area.

49. Parkland Formula
4 cc x WEIGHT (kg) x (% TBSA)

50. Parkland Example 25 year old male weight = 220 pounds
40% TBSA 2° - 3° burns
How much fluid do you need to give?
During the first 8 hours?
During the next 16 hours?

51. first 8 hours = 16,000/2 =8,000/8 = 1,000cc/hr
Parkland Example
4 cc x weight x %TBSA
4 x 100 x 40 = 16,000 cc/24 hours
first 8 hours = 16,000/2 =8,000/8 = 1,000cc/hr
next 16 hours = 8,000/16 = 500cc/hr

52. What do you think? What do you do?
Diarrhea Dysrhythmia
68 yo female on digoxin for chronic CHF, presents to the SIU for colitis as evidenced by copious diarrhea.
The patient is weak and lethargic and ectopic beats are noted on her ECG.
What do you think? What do you do?

53. Hypokalemia Deficits Treatment Serum K =
3-4 is a mEq deficit
2-3 is a mEq deficit
Treatment
replacement 10 mEq/hr via peripheral IV
10 mEq  0.1 mEq/L increase in serum K
Remember to check the Mg level too

54. Paradoxical Aciduria A rule:  0.1 pH   0.4 - 0.5 mEq [K+]
pathophysiology
loss of K, severe alkalosis, [Na+] load
hydrogen exchanged for K
independent of alkalosis remaining
requires emergent replacement

55. What do you think? What do you do?
Cancer
72 yo female with stage 4, metastatic breast cancer.
Patient is confused, cachetic, and nauseated
Na+= 147, Ca+2 = 14mg/dl
What do you think? What do you do?

56. HYPERCALCEMIA Treatment Cancers associated with hypercalcemia
bone
breast
kidney
colon
thyroid
multiple melanoma
Treatment
hydration
diuretics-lasix
mithramycin
corticosteroids
calcitonin- osteoclast resorption
phosphate

57. What do you think? What do you do?
Labor and Delivery
32 year old P3G3 being treated by OB for eclampsia. You are called for a somnolent patient in second-degree heart block and paralysis.
What do you think? What do you do?

58. Hypermagnesemia Signs Treatment Prolonged PR interval
Hypotension, hyporeflexia, paralysis
Treatment
Calcium gluconate
Normal saline
Loop diuretics
dialysis

59. Questions?