Parenteral

Bypasses the alimentary canal (digestive system); id, subq, im, supp, iv

Injections

To go through one or more layers of the skin; used to correct electrolyte and fluid imbalances, provide basic nutrition (TPN), and as vehicles for drugs

Uses of Parenteral Administration

Correct electrolyte and fluid imbalances

Provide basic nutrition (TPN)

Vehicles for drugs

TPN

Total Parenteral Nutrition

Intradermal (ID) Route

Drug injected into superficial layer of skin

Only small volumes used (0.2ml) admin

Generally used for daig. testing; limited vaccines

Slow absorption => slow onset

ID Examples

TB skin test

Small Pox vaccine

Subcutaneous (SC, subq)

Small volumes injected in loose tissue sub. skin

Generally into outer surface of arm/thigh

More rapid response than ID

Intramuscular (IM)

Injection into muscle mass

More rapid absorption than subq

Prolong absorption by using aqueous or oil vehicle

Common IM inj sites/doses

Deltiod muscle in the upper arm (max vol. in adult 2ml)

Gluteal medial muscle hip (max vol. in adult 5 ml)

Intravenous (IV)

Admin into veins for rapid effects

No retreat of drug once admin

Includes emulsions and some emulsions (lipids)

NEVER SUSPENSIONS

Common IV inj sites

Peripheral, central, and other (<= less common)

Peripheral IV

For drugs that do not irritate veins

Isotonic solutions

Used only in short-term IV therapy

Usually used on dorsal forearm surface

Central IV

For admin. of irritating drugs/hypertonic solutions

used in long-term IV therapy or when a peripheral line cannot be maintained

Large veins in thoracic cavity

Subclavian

Used due to high amnt of bld flow, allowing for rapid dilution of solution

Other IV Routes (Less Common)

Intra-arterial (artery)

Intracardiac (heart)

Intra-articular (joint)

Intraspinal (spinal cord *MUST BE PRESERVATIVE-FREE)

Intrasynovial (lining of joint cavity)

Intraethical (brain-spinal cord *MUST BE PRESERVATIVE-FREE)

Common Parenteral Fluids

Dextrose, Sodium Chloride, Sterile Water for Injection, Ringer's Solutions)

D5W

5% dextrose in water

D10W

10% dextrose in water

Normal Saline (NS)

0.9% sodium chloride

Isotonic w/ bld

used in reconstitution of most antibiotics

Isotonic Solutions

same osmotic pressure as surrounding medium (e.g. bld)

Hypotonic Solutions

Lower osmotic pressure than surrounding medium (e.g. bld)

(causes RBCs to lyse)

1/2 NS

0.45% Sodium chloride

Sterile Water for Injection

Not isotonic

Commonly used for reconstitution

Ringer's Solutions

Lactated Ringer's Injection

Ringer's Injection

(the injection is used for fluid and electrolyte replenishment)