importance of Magnesium levels on the critically ill patients and in ICU

1. HYPOMAGNESEMIA IN CRITICALLY
ILL MEDICAL PATIENTS
CS Limaye, VA Londhey, MY Nadkar, NE Borges
FROM JAPI JAN 2011
MODERATORDR. AJEET KR. CHAURASIYA
PRESENTED BY
VINEET MISHRA

4. Magnesium
 50% to 60% contained in bone
 4TH most common cation in the body
 Coenzyme in metabolism of protein and
carbohydrates
 Factors that regulate calcium balance appear to
influence magnesium balance
 Acts directly on myoneural junction
 Important for normal cardiac function

5. Low serum Mg caused by
 Prolonged fasting or starvation
 Shift: Pancreatitis, Insulin administration , Post-
parathyroidectomy
 Chronic alcoholism
 Fluid loss from gastrointestinal tract
 Prolonged parenteral nutrition without
supplementation
 Diuretics, aminoglycosides, cisplatinum, amphotericin

6. Manifestations
 Tremors, tetany , ↑ reflexes, paresthesias of feet and legs,
convulsions
 Positive Babinski , Chvostek and Trousseau signs
 Personality changes with agitation, depression or
confusion, hallucinations
 ECG changes (tall peaked , flat or inverted T waves ; ST
depression , U waves, voltage loss , wide QRS and
prolonged PR)

7. SIGNS
EXCESS
DEFICIENCY
Magnesium (Mg) Hypermagnesaemia
Loss of deep tendon
reflexes (DTRs)
Depression of CNS
Depression of
neuromuscular
function
Hypomagnesaemia
Hyperactive DTRs
CNS changes

8. BACKGROUND
 Hypomagnesaemia is an important but
underdiagnosed electrolyte abnormality in critically ill
patients.
 There are many studies to find the prevalence of
hypomagnesaemia and its effects on mortality and
morbidity in these patients
 Studies have been carried out in intensive care units.


in respiratory intensive care unit
critically ill cancer patient

10. AIMS AND OBJECTIVES
• To study serum magnesium levels in critically ill patients
• To correlate serum magnesium levels with patient
outcome.
• To identify the primary medical conditions associated with
abnormalities of serum magnesium
• To identify the factors predisposing or contributing to
hypomagnesaemia in critically ill patients admitted in a
medical intensive care unit
• To detect other electrolyte abnormalities associated with
hypomagnesemia

11. PARAMETERS
 Length of stay in MICU
 Need for ventilatory support
 Duration of ventilatory support
 APACHE score
 Mortality

12. METHODOLOGY
 Prospective observational study was carried out in the
Medical Intensive Care Unit(from April 2004 to May 2005)
 Hundred patients admitted to the MICU for critical
illnesses were INCLUDED in the study
 Patients who had received magnesium prior to transfer to
MICU were EXCLUDED
 Blood sample was collected for estimation of serum total
magnesium levels

13.  History and clinical findings were noted
 Hematological, biochemical and radiological investigations
were performed
 APACHE score was calculated for each patient on the day of
admission
 Serum total magnesium level (1.7 to 2.4 mg/dl) was
determined by colorimetric method using Titan yellow
 Normal deviate (z) test was applied for quantitative data
and chi-square test was applied for qualitative data

14. CRITICAL DISEASES
• Severe infections like
 complicated malaria,leptospirosis, tetanus,
urinary tract infections, cellulitis, meningitis, pneumonia,
tuberculosis and mucormycosis.
• Hepatic failure
• Acute renal failure
• Chronic renal failure
• Respiratory failure

15.  Congestive cardiac failure
 Cerebrovascular accident
 Poisonings including Organophosphate compounds
 Snake bite
 Acute pancreatitis
 Guillain-Barre syndrome
 Malignancy
 Status epilepticus and
 Diabetic ketoacidosis

17. Study result
Alcoholism
DM
Sepsis
Hypokalemia
Hypoalbuminemia
Normo
Hypocalcemia
Hypo
APACHE
MICU stay
Ventilator days
Ventilator need
Mortality
0
20
40
60
80
Representational values
100

18. CONCLUSION
HYPOMAGNESEMIA AFFECTED/ASSOCIATED WITHHYPOCALCEMIA
HYPOALBUMINEMIA
VENTILATOR NEED
ON VENTILATOR DURATION
SEPSIS
DIABETES MELLITUS
MORTALITY

19. CONCLUSION CONTD. . . . .
HYPOMAGNESEMIA NOT AFFECTED/ASSOCIATED
WITHMICU STAY
APACHE II SCORE
HYPOKALEMIA
ALCOHOLISM (CHRONIC)

20. SUMMARY
 Hypomagnesaemia is a common electrolyte imbalance
in the critically ill patients.
 Whether hypomagnesaemia directly contributes to
cellular alterations leading to increased mortality,
morbidity and poor patient outcome in critically ill
patients or it is just a marker of critical illness is not
clear.
 Hypomagnesaemia is associated with higher mortality
rate in critically ill patients and is also associated with
more frequent and more prolonged ventilatory
support.

21.  It was seen in this study that hypomagnesaemia is
frequently associated with sepsis and diabetes
mellitus.
 Although there was a high incidence of
hypomagnesaemia in the present study, its correction
after magnesium supplementation was not included as
a part of the study.
 The potential benefit of magnesium supplementation
to prevent or correct hypomagnesaemia in critically ill
patients requires further study.

22. MAGNESIUM ESTIMATION
 Specimen: non-hemolyzed serum or lithium heparin





plasma used. EDTA and citrate bind to the Mg.
24hr urine may be used and should be acidified to avoid
Ppt.
Colorimetric method/photometric[TITAN YELLOW]: Mg
binds to calmagite, formazen dye and methylthymol blue
to form a chromogen that is measure at 532- 600nm.
Ca2+ should be eliminated from the sample
AAS- absorbance at 285.2nm
ISE- free Mg with neutral carrier inonophores

23. TAKE HOME MESSAGE
Hypomagnesaemia is NOT A RARE
electrolyte abnormality in critically
ill patients.
Hypomagnesemia should NOT be
misdiagnosed as Hypokalemia.
It should be ordered with Na, K
and Ca serum levels.
REMEMBER HYPOMAGNESEMIA
TOO !!