Dr. Naresh Sharma, MBBS (GMC Jammu) and MD in Internal Medicine (Sher-i-Kashmir Institute of Medical Sciences, SKIMS), is an accomplished physician with extensive experience in both acute and internal medicine. He currently serves as a Registrar in the Department of Medicine at Government Medical College (GMC) Jammu and is an Ex-Registrar of Emergency Medicine at AIMSR, where he gained wide clinical exposure to critical care, shock management, respiratory failure, and complex medical emergencies. Dr. Sharma is presently a Specialist Physician with the Jammu & Kashmir Health Services, where he continues to provide high-quality medical care while actively engaging in clinical teaching, mentoring, and patient-centered practice. Throughout his career, he has managed a vast spectrum of critical and medical conditions in high-intensity settings, making Arterial Blood Gas (ABG) interpretation an essential part of his daily clinical decision-making. His deep interest in clinical physiology and his passion for simplifying complex medical concepts have inspired him to develop this book on Arterial Blood Gas Analysis. With a commitment to building strong foundational understanding among medical students, residents, and practicing clinicians, Dr. Sharma presents a clear, practical, and stepwise approach to ABG interpretation—aimed at strengthening confidence and competence in bedside assessment and emergency care.