This book focuses on the management strategies of complex conditions of frail pediatric patients. The clinical condition of frailty is usually seen as the physiological and multidimensional decline of organ systems related to age: paradoxically, a frailty condition can also occur in children as a disability resulting from various congenital or acquired diseases. The fragile patients are more vulnerable to developing severe clinical events and often need surgical interventions. Moreover, those patients have significant morbidity and lower quality of life. The improvement in managing fragile patients has improved their life expectancy, but in most health care systems, the passage from childhood to adulthood is a critical