What is the maximum dose of Dexmedetomidine ?

This is the dosage information I could find ... but healthcare professionals administering it will know the full details.

Dosage and Administration
Initiation of Procedural Sedation
Adults

IV
Loading dose

1 mcg/kg over 10 min, including awake fiberoptic intubation patients. For patients older than 65 yr of age and for less invasive procedures (eg, ophthalmic surgery), a loading dose of 0.5 mcg/kg over 10 min may be suitable. Consider a dose reduction in patients with impaired hepatic or renal function.
Maintenance dose

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Start with 0.6 mcg/kg/h and titrate to achieve desired clinical effect with doses ranging from 0.2 to 1 mcg/kg/h. Adjust rate of infusion to achieve desired level of sedation. For awake fiberoptic intubation, a maintenance infusion of 0.7 mcg/kg/h is recommended until the endotracheal tube is secured. Consider dose reduction in patients older than 65 yr of age or for patients with impaired hepatic or renal function.
Intensive Care Unit Sedation
Adults

IV
Loading dose

1 mcg/kg over 10 min. Consider a dose reduction in patients older than 65 yr of age or for patients with impaired hepatic or renal function.
Maintenance dose

0.2 to 0.7 mcg/kg/h. Adjust rate of infusion to achieve desired level of sedation. Consider a dose reduction in patients older than 65 yr of age or for patients with impaired hepatic or renal function.
General Advice

* Administer by continuous IV infusion not exceeding 24 h.
* Administer using a controlled infusion devise.
* Preparation of solution is the same for loading and maintenance doses. Dilute with sodium chloride 0.9% to achieve required concentration (4 mcg/mL) prior to administration.
* Do not administer through the same IV catheter with blood or plasma.
* Incompatible with amphotericin B and diazepam.
* Use administration components made with synthetic or coated natural rubber gaskets.

http://www.drugs.com/ppa/dexmedetomidine-hydrochloride.html