Acute respiratory failure:
1) Oxygen saturation <90%,
2) partial pressure of oxygen in arterial blood <60 mmHg or
3) partial pressure of carbon dioxide in arterial blood ≥45 mmHg.

Acute renal failure:
1) Increase in creatinine ≥0.3 mg/dl within 48 hours,
2) increase in creatinine to ≥1.5 times baseline within the prior 7 days, or
3) urine volume <0.5 ml/kg/h for 6 hours

Acute heart failure:
Rapid onset of dyspnea, pulmonary edema and oxygen desaturation requiring urgent therapy

Hypotension:
Persistent systolic blood pressure <90mm/Hg requiring inotropes or aggressive fluid resuscitation

Severe infections:
Pneumonia, empyema, peritonitis, cellulitis > 5cm, suspected typhlitis, enteritis NCI grade 3-4, appendicitis, cholecystitis or other complicated abdominal infections, meningitis, encephalitis, endocarditis and pyelonephritis

Arrhythmias are considered as complications whenever they altered the cardiovascular stability

Patients treated with high-dose chemotherapy (HDC), including induction and intensification for acute leukaemia, BMT, the Magrath regimen and other induction treatments for Burkitt lymphoma, should be excluded