Sending Json response as String and Integers...

{
    "UpdateRequest": {
        "SAASAS": {
            "SPO2": "99.00000",
            "VitalGroupID": "1219",
            "Temperature": "36.6666666666667",            
        },
        "Modified": 1,
        "ID": 25465
    }
}

How can i send VitalGroupID and Temperature as Integer instead of String.... This is the request that get's formed after i hit submit button.