HPE Managing CINV pocket guide 2019 | Page 10

TABLE 2 Classification and characteristics of CINV Classification Characteristics Acute Occurs within the first 24 hours of treatment, possibly between 3 and 16 hours Delayed Occurs after 24 hours, usually for around three days, but can persist for up to five days Anticipatory A conditioned response occurring before each treatment episode; factors include previous poor emetic control Breakthrough Nausea and vomiting that occurs despite recommended CINV prophylaxis Refractory CINV that occurs during subsequent treatment cycles when antiemetic prophylaxis and/or rescue have failed in earlier cycles abnormal tastes and smells), and the vestibular apparatus. Classification of CINV CINV can be classified into five categories: 6–8 • Acute • Delayed • Anticipatory • Breakthrough • Refractory. Each class has a different profile, which is a factor in deciding which antiemetic drugs are most appropriate for its management (Table 2). Acute CINV is described as that occurring within 24 hours 10 | 2019 | hospitalpharmacyeurope.com of chemotherapy administration, although some agents may induce emesis within a few hours. Delayed CINV generally occurs more than 24 hours after chemotherapy and commonly lasts for up to three days, although this may extend to up to five days. Optimal emetic control in the acute phase is essential to prevent delayed CINV in the delayed phase and failure to achieve the former is a strong predictor for the latter. Anticipatory CINV is a conditioned response and is most commonly associated with previous experience of poor