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Overview :
Lichtman et al identified the risk of mortality in patients with
severe malaria based on measures of organ dysfunction at admission to the
intensive care unit (ICU). This can help identify patients who may require more
aggressive management. The authors are from the State Hospital in Windhoek,
Namibia.
Organ systems:
(1) respiratory
(2) cardiac
(3) renal
(4) cerebral
(5) liver
(6) hematologic
|
Organ
System |
Criteria for Organ
Failure On Admission |
|
respiratory |
mechanical ventilation AND alveolar-arterial oxygen
gradient > 100 mm Hg when on ventilatory support |
|
cardiac |
mean arterial pressure < 60 mm Hg with an adequate
filling pressure (by central venous pressure or pulmonary capillary wedge
pressure) |
|
renal |
urine output < 12 mL/kg per day OR serum creatinine
> 150 µmol/L (1.7 mg/dL) |
|
cerebral |
unrousable coma OR grand mal convulsions not caused by
hypoxia, cerebral hypoperfusion, or abnormal chemistries |
|
liver |
total bilirubin > 2 times the upper limit of normal AND
SGPT (ALT) > 2 times the upper limit of normal AND prothrombin index
< 60% |
|
hematologic |
platelet count < 50,000 per µL OR DIC OR severe
hemolysis |
where:
• The
prothrombin index is rarely measured in the US. It measures the percent of the
normal level of prothrombin complex that is present. According to Schulman (New
Engl J Med. 2003; 349: 675-683, Figure 1 page 680; see Chapter 4) an INR of 1.0
indicates 100% and an INR of 1.4-1.6 indicates 40%. I will use an INR of 1.2 to
indicate 60% prothrombin activity.
The presence of >= 3 organ failures was associated with a
high mortality rate. Most of the patients who died had respiratory and/or renal
failure.
In addition, the authors correlated the APACHE II score with
mortality.
|
Apache II Score |
Mortality
Risk |
|
< 17 |
none |
|
17 - 30 |
low to
moderate |
|
> 30 |
high |
Limitations:
• The study
was done at the only ICU in Namibia, which had only 8 beds. Survival would
probably be better in an ICU at a major medical center.
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