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Anatomy of the abdominal viscera: Kidneys, ureters and suprarenal glands
Renal system anatomy and physiology
Renal failure: Pathology review
Anatomy clinical correlates: Anterior and posterior abdominal wall
Anatomy clinical correlates: Inguinal region
Anatomy clinical correlates: Peritoneum and diaphragm
Anatomy clinical correlates: Viscera of the gastrointestinal tract
Anatomy clinical correlates: Other abdominal organs
Appendicitis: Pathology review
Complications during pregnancy: Pathology review
Diverticular disease: Pathology review
Gallbladder disorders: Pathology review
GERD, peptic ulcers, gastritis, and stomach cancer: Pathology review
Inflammatory bowel disease: Pathology review
Mood disorders: Pathology review
Pancreatitis: Pathology review
Anatomy clinical correlates: Female pelvis and perineum
Cervical cancer: Pathology review
Uterine disorders: Pathology review
Extrinsic hemolytic normocytic anemia: Pathology review
Intrinsic hemolytic normocytic anemia: Pathology review
Macrocytic anemia: Pathology review
Microcytic anemia: Pathology review
Non-hemolytic normocytic anemia: Pathology review
Anatomy clinical correlates: Heart
Anatomy clinical correlates: Mediastinum
Anatomy clinical correlates: Pleura and lungs
Anatomy clinical correlates: Thoracic wall
Aortic dissections and aneurysms: Pathology review
Coronary artery disease: Pathology review
Deep vein thrombosis and pulmonary embolism: Pathology review
Pleural effusion, pneumothorax, hemothorax and atelectasis: Pathology review
ECG cardiac infarction and ischemia
Pigmentation skin disorders: Pathology review
Skin cancer: Pathology review
Papulosquamous and inflammatory skin disorders: Pathology review
Anatomy of the abdominal viscera: Esophagus and stomach
Anatomy of the abdominal viscera: Large intestine
Anatomy of the abdominal viscera: Small intestine
Anatomy of the gastrointestinal organs of the pelvis and perineum
Gastrointestinal system anatomy and physiology
Enteric nervous system
Colorectal polyps and cancer: Pathology review
Laxatives and cathartics
Lung cancer and mesothelioma: Pathology review
Nasal, oral and pharyngeal diseases: Pathology review
Obstructive lung diseases: Pathology review
Pneumonia: Pathology review
Tuberculosis: Pathology review
Amnesia, dissociative disorders and delirium: Pathology review
Cerebral vascular disease: Pathology review
Dementia: Pathology review
Electrolyte disturbances: Pathology review
Hypothyroidism: Pathology review
Bile secretion and enterohepatic circulation
Malabsorption syndromes: Pathology review
Bacillus cereus (Food poisoning)
Clostridium difficile (Pseudomembranous colitis)
Vibrio cholerae (Cholera)
Anatomy clinical correlates: Facial (CN VII) and vestibulocochlear (CN VIII) nerves
Cardiomyopathies: Pathology review
Heart blocks: Pathology review
Supraventricular arrhythmias: Pathology review
Valvular heart disease: Pathology review
Ventricular arrhythmias: Pathology review
Vertigo: Pathology review
ECG cardiac hypertrophy and enlargement
ECG normal sinus rhythm
ECG QRS transition
ECG rate and rhythm
Kidney stones: Pathology review
Sexually transmitted infections: Vaginitis and cervicitis: Pathology review
Sexually transmitted infections: Warts and ulcers: Pathology review
Urinary tract infections: Pathology review
Central nervous system infections: Pathology review
Shock: Pathology review
Anatomy clinical correlates: Anterior blood supply to the brain
Anatomy clinical correlates: Temporal regions, oral cavity and nose
Headaches: Pathology review
Traumatic brain injury: Pathology review
Vasculitis: Pathology review
Anatomy clinical correlates: Arm, elbow and forearm
Anatomy clinical correlates: Axilla
Anatomy clinical correlates: Bones, fascia and muscles of the neck
Anatomy clinical correlates: Bones, joints and muscles of the back
Anatomy clinical correlates: Clavicle and shoulder
Anatomy clinical correlates: Foot
Anatomy clinical correlates: Hip, gluteal region and thigh
Anatomy clinical correlates: Knee
Anatomy clinical correlates: Leg and ankle
Anatomy clinical correlates: Median, ulnar and radial nerves
Anatomy clinical correlates: Wrist and hand
Seronegative and septic arthritis: Pathology review
Apnea, hypoventilation and pulmonary hypertension: Pathology review
Heart failure: Pathology review
Nephrotic syndromes: Pathology review
Anatomy clinical correlates: Vertebral canal
Back pain: Pathology review
Anatomy clinical correlates: Male pelvis and perineum
Penile conditions: Pathology review
Prostate disorders and cancer: Pathology review
Testicular and scrotal conditions: Pathology review
Testicular tumors: Pathology review
Anatomy clinical correlates: Eye
Eye conditions: Inflammation, infections and trauma: Pathology review
Eye conditions: Refractive errors, lens disorders and glaucoma: Pathology review
Eye conditions: Retinal disorders: Pathology review
Bronchodilators: Beta 2-agonists and muscarinic antagonists
Bronchodilators: Leukotriene antagonists and methylxanthines
Pulmonary corticosteroids and mast cell inhibitors
Anatomy clinical correlates: Ear
Vaginal and vulvar disorders: Pathology review
Anxiety disorders, phobias and stress-related disorders: Pathology Review
Atherosclerosis and arteriosclerosis: Pathology review
Bone disorders: Pathology review
Diabetes mellitus: Pathology review
Drug misuse, intoxication and withdrawal: Alcohol: Pathology review
Drug misuse, intoxication and withdrawal: Hallucinogens: Pathology review
Drug misuse, intoxication and withdrawal: Other depressants: Pathology review
Drug misuse, intoxication and withdrawal: Stimulants: Pathology review
Dyslipidemias: Pathology review
Hypertension: Pathology review
Movement disorders: Pathology review
Peripheral artery disease: Pathology review
Psychological sleep disorders: Pathology review
Rheumatoid arthritis and osteoarthritis: Pathology review
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Parts of an ECG
An electrocardiogram - an ECG - or the dutch and german version of the word - elektrokardiogram or EKG, is a tool used to visualize “gram” the electricity “electro” that flows through the heart “cardio”.
An ECG tracing specifically shows how the depolarization wave moves during each heartbeat - which is a wave of positive charge - looks from the perspective of different sets of electrodes.
This particular set of electrodes is called lead II, with one electrode on the right arm and the other on the left leg, so essentially when the wave’s moving toward the left leg electrode, you get a positive deflection, like this big positive deflection correspond to the wave moving down the septum.
To read an ECG there are a few key elements to keep in mind, one of them includes figuring out the rate and rhythm. There are a couple ways of figuring out the heart rate on an ECG.
The first one is called the “box method” because you count the number of boxes between heartbeats. Each small box represents 0.04 seconds, and each big box is five small boxes, so each big box is 0.2 seconds.
To do that, you can count the number of small boxes between R waves since R waves are tall and pointy and easy to see in lead 2 of an ECG strip.
You can find an R wave that has a peak that falls at the beginning of a box, and then count up how many boxes until the same point on the next R wave.
Let’s say that there are 4 big boxes and 1.5 small boxes between two R waves, meaning there are 4 x 5 + 1.5 = 21.5 small boxes, and that means there’s 0.04 seconds x 21.5 or .86 seconds between heartbeats.
Now, to get something a little more meaningful we can take the inverse which is 1 over 0.86 beats per second, or 1.16 beats per second.
Now there’re 60 seconds in a minute, so multiplying that by 60 we end up with 70 beats per minute—the heart rate!
Now, if the distance between two R waves is exactly 1 big box, then the heart rate would be 300 beats per minute—really fast. If R waves are two big boxes apart or 0.4 seconds apart, then the heart rate is 150 beats per minute.
Three big boxes apart is 100 beats per minute, four, five, and six big boxes apart is 75, 60, and 50 beats per minute respectively.
Remembering these numbers makes it easier to make a rough estimate. For example, if there are three to four large boxes between R waves, then the heart rate must be between 75 and 100 beats per minute.
Another method to determine the heart rate is to count the number of beats in ten seconds, which is the standard length of time on the rhythm strip portion of a 12-lead ECG.
The heart is a muscle that regularly beats to pump blood throughout the body. An electrocardiogram (ECG) is a test that records the electrical activity of the heart, which shows how fast and strong the heartbeats are.
The heart rate refers to the number of contractions of the heart per minute. This one can vary according to an individual's age, but usually, the normal heart rate for adults falls between 60 and 100 beats per minute. The rhythm refers to the pattern of electrical impulses that cause the heartbeat. The normal cardiac rhythm is a regular sinus rhythm, which means that each heartbeat follows a predictable pattern. There may be abnormal rhythms, such as atrial fibrillation and ventricular fibrillation, both serious and life-threatening conditions.
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