Chapter 15 Marini Pharmacotherapy

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CHAPTER 15 • Pharmacotherapy

to provide pharmacist support because quantifying savings from preventing a drug–drug interaction or an adverse event is often difficult. Quality Improvement Strategies Clinical pharmacists are trained to analyze the medication record, evaluating each medication for indication, efficacy, correct dosing, drug–drug inter- actions, and adverse effects. Daily review of the medication profile often reveals drug duplications (e.g., overlapping narcotics such as oxycodone and hydromorphone), unnecessary medications (e.g., stress ulcer prophylaxis without a clear indication), and competing medications (e.g., heparin and phy- tonadione). Daily review of the medication profile also commonly exposes drug–drug interactions (e.g., warfarin and sulfamethoxazole/trimethoprim or midazolam and fluconazole) and adverse effects (e.g., amphotericin B causing hypokalemia or a beta-lactam antibiotic such as piperacillin/tazobac- tam causing thrombocytopenia). The incidence of adverse effects is magnified by allowing multiple consulting physicians to write medication orders. Numerous ways in which medication practices can A fundamental step in improving medication safety is to establish guidelines and protocols (in written or electronic format) for medications that are fre- quently overlooked, may be used in excess, provide inadequate treatment, are difficult or dangerous to use, or are contraindicated for certain situations/ disease states. Guidelines or protocols help ensure appropri- ate ordering of prophylactic therapy. For example, patients at high risk for developing a stress ulcer should receive prophylaxis to prevent this, but they are not necessary for every patient in the ICU and may carry hazards of their own. Some physicians believe that stress ulcer prophylaxis with either an H2 blocker or a proton pump inhibitor is so inex- pensive that using it for every ICU patient may be beneficial; however, this does not take into account potential drug–drug interactions (e.g., some concur- rent drugs may need acid to be effective) or adverse effects (increased risk of thrombocytopenia, pneu- monia, and possible Clostridium difficile infections). Hence, guidelines may provide criteria for selection of appropriate candidates. be improved are discussed below. Use of Guidelines and Protocols

Another important example is venous thrombo- embolism (VTE) prophylaxis. Without prophylaxis, VTE occurs so frequently in the critically ill that it makes sense to use preventative therapy in almost all patients, but doing so may be overlooked, espe- cially when residents rotate or when physicians change patient assignments. An established and routinely reviewed guideline can help identify those patients who should receive chemical VTE prophy- laxis and those in whom it may be inadvisable. In such cases, nonpharmacological alternatives such as intermittent compression by pneumatic devices should be preferred. The importance of VTE pro- phylaxis has been magnified now that funding and regulatory agencies hold hospitals responsible for potentially preventable thromboembolism. To prevent excessive or inadequate treatment, it is also an excellent idea to develop guidelines for dosing medications to objective end points. Using a validated pain scale to guide opioid dos- ing can achieve better analgesia with fewer side effects. Sedation tools (e.g., Richmond Agitation Sedation Scale) with mandated drug interruptions have been shown to reduce total doses of adminis- tered drugs and to shorten the length of mechani- cal ventilation and ICU stay while lowering costs. The Clinical Institute Withdrawal Assessment of Alcohol (CIWA) scale offers yet another example. In this instance, quantification of symptoms is key to reducing length of stay and total benzodiazepine dose. Protocols help ensure safe pharmacotherapy. Tissue plasminogen activator (tPA) and argatro- ban are examples of drugs that are both potentially dangerous and unfamiliar enough to pose practical problems. For patients with ischemic stroke, tPA is often given, and yet many nurses only use this medication a handful of times during their careers. Because of its high risk for bleeding, it is beneficial to have a protocol for nurses to follow, as tPA must be administered in a very specific time frame and manner. Argatroban is usually only used in patients with suspected or confirmed heparin-induced thrombocytopenia who have a need for therapeutic anticoagulation; therefore, both nurses and physi- cians are likely to use this medication rarely. Again, because of its high bleeding risk, it is beneficial to have an established guideline to prevent complica- tions as well as treatment failures. Protocols or guidelines should be in place for medications used in patients in very high-risk