On Thursday, thousands of registered nurses participated in a one-day strike over benefit cuts at 33 not-for-profit hospitals managed by Kaiser Permanente and Sutter Health, and the independent Children's Hospital Oakland. The California Nurses Association -- the union that organized the strike -- expected nearly 23,000 nurses to participate, but officials could not provide an actual figure. Officials at the affected hospitals said they hired replacement nurses and made other arrangements to limit any possible disruptions to patient care.