1.2 Sodium Imbalance: Hyponatremia

Clinical Manifestations

• Normovolemic

• Hypovolemic

• Hypervolemic

HYPONATREMIA CLINICAL MANIFESTATIONS

• Cardiovascular

  • Note: symptoms vary with changes in vascular volume 

Late manifestation

Skeletal Muscle Weakness

HYPONATREMIA CLINICAL MANIFESTATIONS

• Respiratory

  • Shallow, ineffective respiratory movement is a _______ related to ________ 

Generalized Skeletal Muscle Weakness

Peripheral Neuropathies

Distal

HYPONATREMIA CLINICAL MANIFESTATIONS

• Neuromuscular

  • ___________ that is worse in the extremities 

    • Commonly seen in patient with _________

    • Weakness is often ______ (extremities) 

• Headaches (mid brain swelling)

• Personality changes

• Confusion

• Seizures

• Coma

HYPONATREMIA CLINICAL MANIFESTATIONS

• Central Nervous System

• Nausea

• Increased motility and hyperactive bowel sounds

• Abdominal Cramping and diarrhea

HYPONATREMIA CLINICAL MANIFESTATIONS

• Gastrointestinal

Increased urinary output

HYPONATREMIA CLINICAL MANIFESTATIONS

• Renal

Dry mucous membrane

HYPONATREMIA CLINICAL MANIFESTATIONS

• Integumentary

135 mEq/L

Decreased

HYPONATREMIA CLINICAL MANIFESTATIONS

• Lab Findings

  • Serum sodium level less than _______

  • ________ urine specific gravity 

    • The urine is diluted 

Normovolemic

HYPONATREMIA CLINICAL MANIFESTATIONS

• rapid pulse rate, normal blood pressure 

Hypovolemic

HYPONATREMIA CLINICAL MANIFESTATIONS

• thready, weak, rapid pulse rate, hypotension, flat neck veins (especially when supine), normal or low central venous pressure

Hypervolemic

HYPONATREMIA CLINICAL MANIFESTATIONS

•  rapid, bounding pulse, blood pressure normal or elevated, normal or elevated central venous pressure 

3 seconds

Sympathetic Nervous System

HYPONATREMIA CLINICAL MANIFESTATIONS

• Hypovolemic

  • Normal capillary refill is 2 seconds, but here it is ______indicating that there is reduction in peripheral perfusion (vasocontriction or low cardiac output) 

  • ___________ is activated to preserve the perfusion 

Stroke Volume

Elevated CVP

HYPONATREMIA CLINICAL MANIFESTATIONS

• Hypervolemic

  • Bounding pulse: caused by increased in _________ which _________

Jugular Vein Distention

HYPONATREMIA CLINICAL MANIFESTATIONS

• Hypervolemic

  • excess volume exceeds the preload beyond the heart's capacity = elevated pressure in the venous and pulmonary circulation and might trigger congestion. 

• neuromuscular respiratory compromise 

HYPONATREMIA CLINICAL MANIFESTATIONS

• Respiratory

  • Shallow, ineffective respiratory movement is a late manifestation related to skeletal muscle weakness 

    • Hallmark of __________

    • Shallow pattern minimizes dyspnea . deeper breath require more muscle. 

    • PARADOXICAL BREATHING

Paradoxical Breathing

use of accessory muscles, since there is already a diaphragmatic weakness.

Paradox

exact reverse of normal breathing

Paradoxical Breathing

the chest collapses inwards during inhalation, and there is expansion and bulging during exhalation that is why it is called See-saw breathing. 

• It happens because there are pressure changes in the chest

Deep tendon reflex

HYPONATREMIA CLINICAL MANIFESTATIONS

• Neuromuscular

  • Diminished _________

    • Peripheral nerve dysfunction

Polyneuropathy

Guilliain-Barre Syndrome

When weakness and reduce reflex occur together the clinician often consider presence of _________ including g

ok

CNS symptoms happens because low sodium = low osmolality, the water shifts to the brain cells, causing brain cells to swell therefore there is cerebral edema. It might stretch the pain sensitive structures. 

Nausea

HYPONATREMIA CLINICAL MANIFESTATIONS

• Gastrointestinal

  • Falling serum sodium and fluid shift 

Increased motility and hyperactive bowel sounds

HYPONATREMIA CLINICAL MANIFESTATIONS

• Gastrointestinal

  • There is Gi fluid loss contributing to hypovolemic hyponatremia

Abdominal Cramping and Diarrhea

HYPONATREMIA CLINICAL MANIFESTATIONS

• Gastrointestinal

  • Causes an extra renal sodium loss, and contributes to hypovolemic hyponatremia