Four months after former union minister Jaswant Singh was hospitalised with a severe head injury, the former BJP leader continues to be in coma and shows no sign of improvement, doctors said Tuesday."His (Jaswant Singh) condition is still the same. He continues to be in coma. All the treatment process remains the same with a team of doctors observing him closely every day," a senior doctor at the Army Hospital (Research and Referral) told IANS here."The team of doctors consists of neurosurgeons and critical care specialists. Every effort is being made to revive Jaswant Singh," he added.According to the doctor, Jaswant Singh is being given total parenteral nutrition (TPN) which delivers nutrients intravenously when a patient is unable to eat on his/her own.The 76-year-old leader was admitted to the hospital Aug 8 in a critical condition after his family found him lying on the floor of his house in an unconscious state.