A nurse in the PACU is caring for a client who received isoflurane. Which of the following assessments is the nurse's priority?

A. Hemoglobin level: The hemoglobin level measures the amount of hemoglobin, the oxygen-carrying protein in red blood cells, in the blood. Warfarin is not directly responsible for increasing or decreasing the hemoglobin level. While warfarin can lead to bleeding complications in some cases, it does not specifically target the hemoglobin level, so it is not a direct indicator of the medication's effectiveness.

B. Platelet count: The platelet count measures the number of platelets in the blood, which are essential for blood clotting. Warfarin does not directly affect platelet production or count. It works by inhibiting the production of certain clotting factors, not by affecting platelets. Monitoring the platelet count is important, but it is not an indicator of warfarin's effectiveness in preventing excessive clotting.

C. Prothrombin time (PT) or activated partial thromboplastin time (aPTT): Prothrombin time (PT) and activated partial thromboplastin time (aPTT) are coagulation tests used to assess different types of anticoagulant medications, such as heparin. Warfarin's effect is measured using the International Normalized Ratio (INR). PT and aPTT are not specific to warfarin therapy and are not used to monitor its effectiveness. The INR is the appropriate laboratory test for assessing the efficacy of warfarin therapy.

D. International Normalized Ratio (INR): This is the correct answer. The International Normalized Ratio (INR) is the laboratory test used to monitor the effectiveness of warfarin therapy. The INR measures the time it takes for the blood to clot and reflects the anticoagulant effect of warfarin. A therapeutic INR within the target range (e.g., INR = 2.0 to 3.0 for most indications) indicates that warfarin has been effective in preventing excessive clotting and reducing the risk of complications associated with blood clots.

A. Urinary retention: While urinary retention can be a side effect of meperidine and other opioids, it is not the priority assessment before administering the medication. Urinary retention is a concern but is not immediately life-threatening compared to other potential side effects of opioids, such as respiratory depression. Assessing urinary retention is important, but it is not the primary concern in this situation.

B. Vomiting: Vomiting can also be a side effect of opioids, including meperidine. While it is essential to assess for vomiting and its potential impact on the client's overall condition, it is not the priority assessment before administering the medication. Vomiting can be managed, and the nurse should address it as needed. However, the priority assessment is one that can affect the client's immediate safety and well-being, such as respiratory rate and potential respiratory depression.

C. Respiratory rate: This is the correct answer. The priority assessment before administering meperidine is the client's respiratory rate. Opioids can cause respiratory depression, leading to reduced breathing and inadequate ventilation. Monitoring the respiratory rate allows the nurse to detect any signs of respiratory distress or inadequate breathing, enabling them to intervene promptly to prevent serious complications.

D. Level of consciousness: While assessing the client's level of consciousness is essential for overall assessment and monitoring, it is not the priority assessment before administering meperidine. Respiratory depression due to opioid use can occur even when the client is conscious. However, if respiratory depression occurs, it can lead to a decrease in consciousness and potentially unconsciousness, making the assessment of respiratory rate more critical to prevent such complications.