Background Infusion Rate

Nonetheless, routine use of background infusion has been questioned, especially when opioids are administered systemically (intravenously) by PCA. It appears that background infusions may not provide any additional analgesic benefits in most patients, but they can lead to an increased risk of side effects such as respiratory depression because patients ultimately receive a larger total amount of opioid (i.e., the background infusion plus the demand doses).8,34 Hence, background infusion rates have been discouraged for 

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Reactivation of latent tuberculosis is a major concern with infliximab (SEDA-26, 402), and accounts for about one-third of infections in these patients. According to data from the manufacturers, 130 cases of active tuberculosis were notified up to October 2001. Many of the cases were disseminated or extrapulmonary tuberculosis, and several patients died. Several case reports have provided detailed information in at least seven other patients, including three who developed miliary tuberculosis and one who developed Mycobacterium tuberculosis enteritis (44-48). A detailed analysis of 70 cases of tuberculosis reported to the FDA has been published (49). Two-thirds of the cases were noted after three or fewer infusions and 57% of the patients had extrapulmonary disease. There were 64 cases from countries with a low incidence of tuberculosis. From these reports and the number of patients treated with infliximab, the estimated rate of tuberculosis in patients with rheumatoid arthritis treated with infliximab was four times higher than the background rate. Patients with evidence of active infection should not receive infliximab until the infection is under control all should be screened for tuberculosis before starting infliximab (50). From these and other data it has been estimated that the risk of tuberculosis in the first year of infliximab treatment is 0.035 in US citizens and 0.2% in non-US citizens. Further investigations, such as a chest X-ray and a Mantoux test, and prophylactic treatment with isoniazid, will show whether the incidence can be reduced in patients taking anti-TNF treatment (51). 

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