Final answer:
The main problem experienced by the Department of Internal Medicine is a lack of collaboration among departments, leading to doctor resignations and negative consequences for patient care and satisfaction.
Step-by-step explanation:
The main problem experienced by the Department of Internal Medicine in this case is a lack of collaboration among departments. This lack of collaboration has led to doctor resignations due to patient complaints. The implications of this problem are decreased patient satisfaction, compromised patient care, and a negative impact on the reputation of the hospital.