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Guidelines for the treatment of malaria – 2 edition
anaemia where there has been adaptation and a compensatory right shift in the oxygen
dissociation curve.
8.10.4 Exchange blood transfusion
There have been many anecdotal reports and several series claiming benefit for exchange
blood transfusion (EBT) in severe malaria but no comparative trials, and there is no
consensus on whether it reduces mortality or how it might work. The rationale for EBT
has been variously proposed as:
• removing infected red blood cells from the circulation and, therefore, lowering the
parasite burden (although only the circulating relatively non-pathogenic stages are
removed; this is also achieved rapidly with artemisinin derivatives);
• reducing rapidly both the antigen load and the burden of parasite-derived toxins,
metabolites and toxic mediators produced by the host; and
• replacing the rigid unparasitized red cells by more deformable cells and, therefore,
alleviating microcirculatory obstruction.
Exchange blood transfusion requires intensive nursing care and a relatively large volume
of blood, and it carries significant risks. There is no consensus on the indications, benefits
and dangers involved, or on practical details such as the volume of blood that should
be exchanged. It is, therefore, not possible to make any recommendation regarding the
use of EBT.
8.10.5 Use of anticonvulsants
The treatment of convulsions in cerebral malaria with intravenous (or, if this is not
possible, rectal) benzodiazepines or intramuscular paraldehyde is similar to that for
repeated seizures from any cause. In a large double-blind placebo-controlled evaluation
of a single prophylactic intramuscular injection of 20 mg/kg body weight of phenobarbital
(phenobarbitone) in children with cerebral malaria there was a reduction in seizures,
but a significant increase in mortality in phenobarbital recipients. This resulted from
respiratory arrest, and it was associated with additional benzodiazepine use. A 20 mg/kg
dose of phenobarbital should not be given without respiratory support, but whether
a lower dose would be effective and safer, or whether if ventilation is given, mortality
would not be increased is not known. In the absence of further information, prophylactic
anticonvulsants are not recommended.
8.10.6 Concomitant use of antibiotics
The threshold for administering antibiotic treatment should be low in severe malaria.
Septicaemia and severe malaria are associated and there is a diagnostic overlap, particularly
in children. Unexplained deterioration may result from a supervening bacterial infection.
Although enteric bacteria (notably Salmonella) have predominated in most trial series,
a variety of bacteria have been cultured from the blood of patients diagnosed as having
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