In the sentence extracted from biomedical literature, identify all the chemical entities. The required answer format is the same sentence with HTML <span> tags to mark up specific entities. 
### Entity Markup Guides:
Use <span class="chemical"> to denote a chemical.

### Input Text: CONCLUSIONS : Ketamine reliably , safely , and quickly provided adequate sedation to effectively facilitate the reduction of children ' s fractures in the emergency department at our institution .
### Output Text:
CONCLUSIONS : <span class="chemical">Ketamine</span> reliably , safely , and quickly provided adequate sedation to effectively facilitate the reduction of children ' s fractures in the emergency department at our institution . 