• ECG
• Echocardiography
• Chest X-ray
• Arterial blood gases, pH and lactate (high lactate not necessarily indicative of ischaemic tissue, may be raised by direct effect of catecholamines on cellular metabolism)
• Blood metadrenaline, normetadrenaline and dopamine concentration
• Full blood count
• Coagulation screen
• Biochemical profile
• Triple phase adrenal CT scan (or in and out of phase adrenal MRI)

Later

• Base of skull to pelvis imaging if adrenal imaging negative
• Nuclear medicine imaging (I123-mIBG)
• Further investigation to be directed by neuroendocrine tumour multidisciplinary team