The COVID-19 pandemic has had a severe impact on nursing care. This cross-sectional survey-based study compared aspects of nursing care and nurses' satisfaction with care provided before and during the first wave of the COVID-19 pandemic. A total of 936 registered nurses (RNs) rated the frequency with which they performed fundamental care, nursing techniques, patient education, symptom management, and nurse-patient relationships before and during the pandemic. A recursive partitioning for ordered multivariate response in a conditional inference framework approach was applied. More frequent fundamental cares were associated with their frequency before the pandemic (p < 0.001), caring for COVID-19 patients (p < 0.001), and workplace reassignment (p = 0.004). Caring for COVID-19 patients (p < 0.001), workplace reassignment (p = 0.030), and caring for ≤7.4 COVID-19 patients (p = 0.014) increased nursing techniques. RNs in high-intensity COVID-19 units (p = 0.002) who educated patients before the pandemic, stopped this task. RNs caring for COVID-19 patients reported increased symptom management (p < 0.001), as did RNs caring for more non-COVID-19 patients (p = 0.037). Less frequent nurse-patient relationships before the pandemic and working in high-intensity COVID-19 units decreased nurse-patient relationships (p = 0.002). Despite enormous challenges, nurses continued to provide a high level of care. Ensuring the appropriate deployment and education of nurses is crucial to personalize care and to maintain nurses' satisfaction with the care provided.