Contraindications, determination

Once the hazard and exposure assessments ate complete for any specific hazard, it is relatively simple to determine how many people will be affected and the severity of the effect (i.e., the risk). It is considerably more difficult to decide whether these risks are warranted compared to the benefits. This is particularly true if the risks are uncertain, involuntary, or not understood by those at risk if those at risk are not primarily those who benefit or if alternatives are unknown, uncertain, or impractical. The process is complex because the goals are multiple and frequently contraindicating. 

Review patient s medical record to determine contraindications for each medication. For aspirin, P-blockers, ACE inhibitors, and ARBs, document contraindications in patient s medical record. 

Once absorbed, ezetimibe undergoes extensive glucuronida-tion in the intestinal wall to the active metabolite (ezetimibe glucuronide). Ezetimibe and the active metabolite are entero-hepatically recirculated back to the site of action, which limits systemic exposure and may explain the low incidence of adverse effects (Table 9-9). Ezetimibe alone or with a statin is contraindicated in patients with active liver disease or unexplained persistent elevations in LFTs. Currently, clinical trials designed to determine ezetimibe s effects on CHD morbidity and mortality have not been completed. The time until maximum effect on lipids for ezetemibe is generally 2 weeks. 

If endogenous Cushing s syndrome, determine if patient is an appropriate candidate for surgical resection of the tumor. Does the patient have any conditions that contraindicate surgical resection, such as advanced disease (metastatic adrenal carcinoma) ... 

Evaluate the patient for the presence of surgical contraindications to transsphenoidal microsurgery. Determine if the patient is able or willing to undergo surgical intervention. 

As discussed later in this chapter, contraindications exist for various forms of contraception. Patients must be evaluated completely by a health care professional to rule out any medical contraindications to certain contraceptives. The physical examination also will allow health care professionals to determine if there are other medical concerns, such as hypertension, diabetes, or liver disease, that need to be considered when determining the appropriate contraceptive agent. Clinicians also should review family history for potential risks with certain forms of birth control. 

For penicillin-allergic adults, use a fluoroquinolone (ciprofloxacin 0.5-0.75 g orally every 12 hours or 0.4 g IV every 12 hours levofloxacin 0.5-0.75 g orally or IV every 24 hours or moxifloxacin 0.4 g orally or IV every 24 hours). eGentamicin or tobramycin, 2 mg/kg loading dose, then maintenance dose as determined by serum concentrations, fluoroquinolone or aztreonam 1 g IV every 6 hours may be used in place of the aminoglycoside in patients with severe renal dysfunction or other relative contraindications to aminoglycoside use. 

Electrocardiographic assessment Prior to administration of the first dose, the QT interval must be determined using an average of 5 beats. If the baseline QT is greater than 450 msec (JT 330 msec or more if QRS over 100 msec), Betapace AF s contraindicated. 

Opioids are contraindicated in head trauma because of the risk of a rise in intracranial pressure from vasodilation and increased cerebrospinal fluid volume. In addition, in such patients the onset of miosis following opioid administration can mask the pupillary responses used diagnostically for determination of concussion. 

Zanamivir is contraindicated in individuals with severe or decompensated chronic obstructive lung disease or asthma because it has not been shown to be effective in these individuals and can cause serious adverse pulmonary reactions. Individuals with mild to moderate asthma may have a decline in lung function when taking zanamivir. The safety and efficacy of this medication have not been determined in individuals with severe renal insufficiency. No clinically significant drug interactions have been reported. Zanamivir does not decrease the effectiveness of the influenza vaccine. 

Because of the potential for hematological and hepatic toxicity, carbamazepine should not be administered to patients with liver disease or thrombocytopenia or to those at risk for agranulocytosis. For this reason, carbamazepine is strictly contraindicated in patients receiving clozapine. Because of reports of teratogenicity, including increased risks of spina bifida (Rosa 1991), microcephaly (Bertol-lini et al. 1987), and craniofacial defects (Jones et al. 1989), carbamazepine is relatively contraindicated in pregnant women. Pretreatment evaluation should include a complete blood count and determination of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels. 

Cross-match Cross-matching is the process of testing the cells of a prospective organ donor with the serum of a prospective organ recipient for compatibility. The flow cytometric cross-match determines whether serum from the recipient contains antibodies that bind to the donor cells. Such binding constitutes a positive cross-match and is a contraindication to transplantation in that particular donor/recipient combination. 

The availability of scanning equipment and trained personal, specific contraindications, patient claustrophobia, and the safety of the sometimes very ill or uncooperative stroke patients limit the feasibility of stroke MRI during the scan. To determine the true feasibility of MRI requires a prospective study in all patients presenting with suspected stroke. Singer et al. (2004) found that only 80% of 144 stroke patients recruited at the hospital door could be examined with MRI. Others reported even smaller numbers between 54% and 62% of the patients in whom MRI was feasible (Barber et al. 2005 Hand et al. 2005 Schramm et al. 2004). According to Barber et al. (2005) and Hand et al. (2005), feasi-... 

Selection Bias The volunteers received careful physical and mental screening examinations for contraindications to the planned tests. The health of a volunteer helped to determine the type of test in which he participated. The more healthy men were exposed to the active chemicals, and the less healthy were used as controls and in some cases tested equipment without being exposed to chemicals. Such selection bias means that the men not exposed to chemicals would be expected to have more illness therefore, the likelihood of discovering effects in them (whether early or late) due to the treatments would be smaller. 

For a time, the CSM seemed determined to make Prozac contraindicated in underweight, anorexic, or agitated patients, but apparently, nothing came of it. 

NSAIDs are the first-line agents for treating an acute attack of gout, providing there are no contraindications. Indometacin and diclofenac are the agents most frequently used. Alldred and Capstick (2007) state that the most important factor determining therapeutic success is not the NSAID chosen but how soon NSAID therapy is initiated. Treatment should continue until all symptoms have resolved. 

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