The goal of this handbook or companion book is to provide students and residents a practical and systematic framework or a “how-to” and “hands-on” focus for initiating and imparting patient care mainly at the bedside and elsewhere. This book has been conceptualized so that students and residents can use it as a quick referral and also as a guide during teaching and at the time of examination. API Textbook is a source of theory and practical knowledge. This book focuses on practical approaches and considerations.