Sentence:  Of particular relevance to the ICU [intensive care unit] setting is ketorolac, a NSAID [non-steroidal anti-inflammatory drug] that is being increasingly used for pain control in order to avoid problems of respiratory depression, sedation, and addiction associated with narcotics. ... ICU patients, who typically are under great stress from an <WSD>acute</WSD> illness that is often accompanied by multiorgan dysfunction including renal insufficiency, are especially prone to develop renal complications from ketorolacnb.... 
Meaning of the word marked with <WSD> tags:  Of an abnormal condition of recent or sudden onset, in contrast to delayed onset; this sense does not imply severity, unlike the common usage.