Fluids, Electrolytes, and Acid-Base Balance Lecture Notes (Typed)

Vocabulary practice flashcards covering Weeks 6 and 7 lecture notes on fluid and electrolyte imbalances, arterial blood gas components, and acid-base disorders.

Peripheral Edema Mechanisms (Heart Failure)

Mechanisms contributing to peripheral edema in heart failure, including increased hydrostatic pressure in capillaries, decreased plasma oncotic pressure, increased sodium and water retention, and impaired lymphatic drainage.

T Wave

An electrocardiogram waveform altered in hyperkalemia.

U Wave

An electrocardiogram waveform associated with hypokalemia.

Ionized Calcium

The specific laboratory value to check when albumin levels are low, which causes low total calcium.

Parathyroid

The gland that controls calcium balance; its removal results in hypocalcemia.

Hypermagnesemia

An electrolyte imbalance characterized in the lecture notes as fast and excited.

Normal Blood $pH$ Range

The physiological blood $pH$ span of $7.35 - 7.45$, where values below $7.35$ represent acidosis and values above $7.45$ represent alkalosis.

Carbonic Acid-Bicarbonate Buffer Equation

The reversible reaction $CO_2 + H_2O \rightleftharpoons H_2CO_3 \rightleftharpoons HCO_3^- + H^+$, where $CO_2 + H_2O$ represents the respiratory component and $HCO_3^- + H^+$ represents the metabolic component.

Acid Blood Central Nervous System Effect

The physiological effect of acidotic blood, which acts as a central nervous system depressant.

Basic Blood Central Nervous System Effect

The physiological effect of alkalotic blood, which acts as a central nervous system stimulant.

$$PaCO_2$$

The respiratory component of arterial blood gases with a normal range of $35 - 45\,\text{mmHg}$.

$$HCO_3^-$$

The metabolic component of arterial blood gases handled by the kidneys, with a normal range of $22 - 26\,\text{mmol/L}$.

$$PaO_2$$

Arterial oxygen pressure measuring dissolved oxygen in arterial blood with a normal range of $80 - 100\,\text{mmHg}$; it does not determine acidosis or alkalosis.

Buffer Systems

Physiological and chemical systems that resist sudden changes in $pH$.

Hemoglobin Buffer Action

The mechanism whereby deoxygenated hemoglobin binds $H^+$ to form $HHb$, decreasing free $H^+$ and preventing a fall in $pH$.

Buffer Response Times

The onset durations of buffer systems: chemical buffers and red blood cells act immediately, the respiratory system acts in minutes, and the renal system acts in hours to days.

Respiratory Acidosis

An acid-base imbalance characterized by $\uparrow PaCO_2$ and $\downarrow pH$. Causes include drug-induced respiratory depression, neurological impairment, COPD, airway obstruction, severe pneumonia, respiratory failure, and neuromuscular weakness. Manifestations include headache, confusion, drowsiness, decreased level of consciousness, and possible dysrhythmias.

Respiratory Alkalosis

An acid-base imbalance caused by excess $CO_2$ loss, characterized by $\downarrow PaCO_2$ and $\uparrow pH$. Causes include anxiety, pain, hyperventilation, excessive mechanical ventilator use, fever, sepsis, hypoxemia, and pulmonary embolism. Manifestations include lightheadedness, dizziness, muscle cramps, spasms, and confusion in significant cases.

Metabolic Acidosis

An acid-base imbalance caused by acid accumulation or bicarbonate loss, characterized by $\downarrow HCO_3^-$ and $\downarrow pH$. Causes include diabetic ketoacidosis (DKA), lactic acidosis from shock or poor tissue perfusion, kidney failure, severe diarrhea, and certain toxic exposures. Manifestations include deep rapid breathing, weakness, nausea, vomiting, confusion, reduced consciousness, possible hypertension, and dysrhythmias.

Metabolic Alkalosis

An acid-base disorder characterized by $\uparrow HCO_3^-$ and $\uparrow pH$. Causes include repeated vomiting, nasogastric suction, diuretic-associated fluid and chloride loss, excessive alkali intake, and mineralocorticoid excess. Manifestations include weakness, muscle cramps, tingling, neuromuscular excitability, hypoventilation (to retain $CO_2$), and possible dysrhythmias.

Uncompensated Pattern

An arterial blood gas state in which the $pH$ is abnormal while the other compensatory component has not changed.

Partially Compensated Pattern

An arterial blood gas state in which the $pH$ is abnormal and the other factors are abnormal in a pattern consistent with compensation.

Fully Compensated Pattern

An arterial blood gas state in which the $pH$ has returned to the normal range while both $PaCO_2$ and $HCO_3^-$ remain abnormal.

Sodium Bicarbonate

An alkalizing agent administered in acidosis to boost basic levels; requires monitoring of cardiovascular, respiratory, and neurological systems and cautious administration with acidifying drugs.

Ammonium

An acidifying agent administered in alkalosis to acidify blood; must be given at a rate of no more than $5\,\text{mL/h}$ to prevent toxicity, with monitoring for acidosis manifestations and renal status.