Читать книгу Emergency Medical Services - Группа авторов - Страница 479

Perhaps the most well‐known and feared complication of renal failure is that of hyperkalemia. The healthy kidney excretes 95% of the daily potassium intake [12]. Fatal arrhythmias are most likely to occur with serum levels over 9 mEq/L [13]. Hyperkalemia is associated with poor outcomes in both the general population and in patients with renal disease. It has been found to be an independent predictor of inpatient mortality [14]. Nonetheless, a patient with CKD can often tolerate higher levels of potassium than a healthy individual can and generally has a lower risk of mortality for any given serum potassium level as compared with the general population [15]. In contrast to other electrolyte abnormalities, the patient with hyperkalemia may not voice any specific complaints. The ECG is often used as a screening test for electrolyte disturbance, but it has overall poor sensitivity and specificity (Figures 22.1 and 22.2). ECG tracing changes that may be seen in hyperkalemia are listed in Table 22.1. While it is an easy and noninvasive test, the EMS clinician must not exclusively rely on an ECG for patient evaluation [13]. Specific management of hyperkalemia will be addressed later in the chapter.

Figure 22.1 ECG of a patient with hyperkalemia. Note wide complex tachycardia and development of sine wave.

Figure 22.2 ECG of patient with hyperkalemia with junctional bradycardia.