Treatment of Complicated Malaria

Diagnosis and Treatment

• The World Health Organization (WHO) criteria for diagnosing complicated malaria include impaired consciousness, multiple convulsions, prostration, bleeding, acute renal failure, pulmonary edema, acidosis, hyperlactatemia, severe anemia, hypoglycemia, high parasitemia, jaundice, and renal impairment 1
• Intravenous artesunate is the first-line treatment for complicated malaria and should be administered immediately as a medical emergency, providing faster parasite clearance and shorter ICU stays compared to quinine 2, 3, 4
• The WHO recommends intravenous artesunate for 3 doses, followed by a full course of oral artemisinin-based combination therapy (ACT) once the patient improves 2, 4
• The American Society of Tropical Medicine and Hygiene and other international guidelines support the use of intravenous artesunate as the first-line treatment for severe malaria 2

Supportive Management

• Restrictive fluid management should be used to avoid pulmonary or cerebral edema, without worsening kidney function or tissue perfusion 2
• Acetaminophen may have reno-protective effects in patients with acute kidney injury and can be considered at a dose of 1g every 6 hours for 72 hours 2, 4
• Antibiotics should be started in cases of suspected bacterial co-infection but continued only if blood cultures are positive 2
• Exchange blood transfusion is not recommended as it has not been shown to improve outcomes 2, 4

Monitoring During Treatment

• Parasitemia should be monitored every 12 hours until it declines to <1%, then every 24 hours until negative 2, 5
• Physiological monitoring, including cardiocirculatory, pulmonary, kidney, and metabolic parameters, should be continuous 2
• Glycemia, plasma bicarbonate, and lactate levels should be monitored 2
• Post-artesunate delayed hemolysis (PADH) should be monitored by checking hemoglobin, haptoglobin, and lactate dehydrogenase levels at days 7, 14, 21, and 28 2, 5

Administration of Artesunate After Artemether in Malaria Treatment

Rationale for Sequential Administration

• When transitioning between artemisinin derivatives, there is no contraindication to administering artesunate after artemether, as both work through the same mechanism of parasite clearance 6

Treatment Protocol for Severe Malaria

• For severe malaria, intravenous artesunate should be administered at 2.4 mg/kg body weight at 0, 12, and 24 hours, and then daily until oral medication can be taken 7
• If injectable artesunate is unavailable, intramuscular artemether can be used at 3.2 mg/kg on admission followed by 1.6 mg/kg daily 7

Clinical Considerations

• Monitoring of peripheral blood parasitemia should be done every 12 hours after starting treatment until a decline to <1% is observed, then every 24 hours until negative results 6
• For patients treated with IV artesunate, monitoring for post-artesunate delayed hemolysis (PADH) at days 7, 14, 21, and 28 is warranted 8

Completion of Treatment

• After parenteral therapy with either artemether or artesunate, patients should be switched to a complete course of oral artemisinin-based combination therapy (ACT) once they are clinically improved and able to take oral medication 6

Artesunate's Role in Malaria Treatment

Evidence on Artesunate and Fever Management

• The World Health Organization recommends that hyperpyrexia in malaria treatment be managed with antipyretics, such as ibuprofen or paracetamol, or tepid sponging, rather than artesunate 9
• When fever management is needed in malaria patients, ibuprofen is considered superior to paracetamol for reducing fever in cases without renal impairment, according to the British Medical Journal 9

Antipyretic Management in Malaria

• For patients with malaria who develop hyperpyrexia, the American Society of Tropical Medicine and Hygiene suggests that specific antipyretic medications should be administered, including ibuprofen as the preferred antipyretic when renal function is normal, and tepid sponging as a non-pharmacological approach to fever reduction 9

Clinical Considerations for Artesunate Use

• When treating patients with severe malaria, both antimalarial therapy, such as artesunate, and separate antipyretic management are required, as stated by the Centers for Disease Control and Prevention 9

Intravenous Artesunate Dosing for Plasmodium falciparum Malaria

Dosing Regimen Details

• For treatment of complicated Plasmodium falciparum malaria, intravenous artesunate should be administered at 2.4 mg/kg body weight at 0, 12, and 24 hours, then continued at 2.4 mg/kg daily until the patient can take oral medication 10, 11, 12
• The recommended dosing schedule is:
  • Initial dose: 2.4 mg/kg IV at 0 hours 11
  • Second dose: 2.4 mg/kg IV at 12 hours 11
  • Third dose: 2.4 mg/kg IV at 24 hours 10
  • Subsequent doses: 2.4 mg/kg IV daily 10, 11, 12
• Continue IV artesunate until patient can tolerate oral medication and parasite density has decreased to <1% 10, 11, 12

Transition to Oral Therapy

• Preferred oral options include dihydroartemisinin-piperaquine or artemether-lumefantrine 10, 11, 12

Alternative Treatment Options

• If intravenous artesunate is unavailable, intravenous quinine dihydrochloride can be used as a second-line option 10, 11, 12
• Quinine dosing: 20 mg salt/kg loading dose over 4 hours, followed by 10 mg/kg over 4 hours starting 8 hours after initiation, and then every 8 hours 10, 11, 12
• Switch to oral therapy as soon as feasible, but not before completing 48 hours of IV treatment 10, 11, 12

Guidelines for Discontinuation of Intravenous Artesunate in Severe Malaria

Stopping Criteria

• Discontinue IV artesunate after at least three doses (0 h, 12 h, 24 h) and switch to oral therapy only when the patient is hemodynamically stable, conscious, able to tolerate oral intake, and peripheral parasitemia has fallen to < 1 % of red blood cells. 13

Dosing Schedule Before Discontinuation

• Administer IV artesunate at 2.4 mg/kg at 0 h, 12 h, and 24 h (first three doses).
• Continue 2.4 mg/kg IV once daily after the first 24 h until all stopping criteria are satisfied.
• Do not stop earlier than the initial three doses, even if the patient appears improved. 13

Transition to Oral Therapy

• Immediately after meeting stopping criteria, begin a full 3‑day course of an oral artemisinin‑based combination therapy (ACT).
• Preferred ACT options are artemether‑lumefantrine or dihydroartemisinin‑piperaquine.
• The oral ACT course is a complete treatment; it must be given for the full three days regardless of the number of IV artesunate days administered. 13

Monitoring Requirements During Treatment

Parasitemia Monitoring

• Measure peripheral parasitemia every 12 hours until it declines to < 1 %.
• Once < 1 % is reached, check parasitemia every 24 hours until it becomes negative.
• An initial increase in parasite density within the first 24 hours does not indicate treatment failure. 13

Post‑Treatment Surveillance

• Screen for post‑artesunate delayed hemolysis (PADH) by assessing hemoglobin, haptoglobin, and lactate dehydrogenase on days 7, 14, 21, and 28 after completion of IV artesunate.
• PADH occurs in approximately 10–15 % of patients treated with IV artesunate. 13

Common Pitfalls to Avoid

• Do not stop IV artesunate after only three doses if the patient cannot yet tolerate oral intake; continue once‑daily IV dosing until oral tolerance is achieved. 13
• Do not switch to oral ACT while parasitemia remains ≥ 1 %, as adequate parasite clearance has not been achieved. 13
• Do not shorten the oral ACT regimen; a complete three‑day course is mandatory after IV artesunate cessation. 13
• Do not delay PADH monitoring; the complication can arise up to four weeks post‑treatment and requires systematic surveillance. 13

Intravenous Artesunate Administration for Severe Plasmodium falciparum Malaria

Immediate Dosing Protocol

Parasitemia Monitoring

Laboratory Monitoring During Therapy

Intravenous Artesunate Administration in Severe Malaria

Administration Technique

• Administer the initial dose of intravenous artesunate as a rapid IV bolus over several minutes to achieve immediate therapeutic drug levels in patients with severe malaria, as recommended by the Intensive Care Medicine guideline (2012) 16.

Hemodynamic Stability Requirement for Discontinuation

• Intravenous artesunate should be stopped only after the patient is hemodynamically stable (adequate blood pressure and perfusion), in line with the Intensive Care Medicine recommendation (2012) 16.