Integrated Physiology and Pathophysiology

Renal physiology

C.J. is a 52-year-old male with chronic hypertension (HTN) managed both with lifestyle changes and pharmacologically. He presented yesterday morning to an outside hospital with malignant HTN, headache, and complaints of “tearing” chest pain. His only past medical history is…

Micturition

Introduction Micturition is the process by which the urinary bladder empties its contents, and it is more commonly known as urination. This process involves two steps: (1) the bladder fills until wall tension exceeds a certain threshold level and (2)…

Acid-base homeostasis

Introduction Bodily processes are exquisitely sensitive to pH. Deviations from the normal range of blood pH of 7.35 to 7.45 may have serious consequences. Low pH (<7.2) causes significant clinical manifestations, including impaired growth, decreased cardiac output, decreased blood pressure,…

The regulation of potassium balance

Introduction In the past few chapters, we made several observations about extracellular fluid (ECF) volume and osmolality: The stability of these parameters is critical for normal physiologic functioning These parameters are subject to daily changes The kidney counters these changes…

Osmoregulation

Introduction Osmolality (or concentration of the solutes in the body fluids) is critical to organ function and must be closely regulated. Disturbances in the osmolality of the body fluids arise from the gain or loss of water, or from the…

Tubular transport

Introduction The body faces multiple challenges met by the kidneys, including acid base balance, regulation of the concentrations of electrolytes such as potassium, and control of blood pressure. Two of the most critical are (1) the management of extracellular fluid…

Renal structure and function

Introduction The kidney is the principal organ of homeostasis. The kidney’s filtration of blood, and modification of that filtrate by epithelial transport, produces urine to accomplish the following functions: Control of the composition of body fluids, the concentration of electrolytes,…

Pulmonary physiology

A.Y. is a 33-year-old woman with a history of severe asthma requiring multiple admissions and intubations, who initially presented to the emergency room with shortness of breath, wheezing, and chest pain. Presentation: History A.Y. had been in her usual state…

The regulation of breathing

Core concepts ( figs. 16.1 and 16.2 ) To function properly, the human respiratory system must: Respond to oxygen demands. Maintain a constant range of oxygen and carbon dioxide in blood. Respiration is governed by both voluntary and involuntary neural…