ischemia

DEFINITION of ischemia

Ischemia is a pathophysiological condition in which blood flow — and therefore oxygen and nutrient delivery — to a tissue is reduced or completely obstructed. This can result from arterial narrowing (stenosis), thrombosis, embolism, vasospasm, or systemic hypoperfusion. If prolonged, ischemia progresses to infarction (irreversible tissue death). The severity depends on the organ affected, duration of deprivation, availability of collateral circulation, and metabolic demands of the tissue.

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ETYMOLOGY of ischemia

greek isch- Greek ischein (ἰσχαίνω) to hold back, restrain, suppress -emia Greek haima (αἷμα) blood Literally: “holding back of blood” First used in modern medical literature in the 19th century.

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🔑 SPECIALTY-RELEVANT ICD-10-CM CODES

👁️ Ophthalmology

Code	Description
H35.82	Retinal ischemia

🫘 Urology

Code	Description
N28.0	Ischemia and infarction of kidney

🧠 Neurology/General

Code	Description
I67.82	Cerebral ischemia (chronic)
P91.0	Neonatal cerebral ischemia

❤️ Cardiac

Code	Description
I25.6	Silent myocardial ischemia
P29.4	Transient myocardial ischemia in newborn

🦴 Musculoskeletal / Trauma

Code	Description
T79.6XXA	Traumatic ischemia of muscle — initial encounter
T79.6XXD	Traumatic ischemia of muscle — subsequent encounter
T79.6XXS	Traumatic ischemia of muscle — sequela

🫁 Intestinal

Code	Description
K55.011	Focal acute (reversible) ischemia of small intestine
K55.012	Diffuse acute (reversible) ischemia of small intestine
K55.031	Focal acute (reversible) ischemia of large intestine
K55.032	Diffuse acute (reversible) ischemia of large intestine

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💡 CODING TIPS (Inpatient)

• Ischemia ≠ Infarction — always distinguish. If the physician documents infarction, code it as such (e.g., renal infarction still falls under N28.0, but myocardial infarction uses the I21.x series).
• For retinal ischemia (H35.82), verify whether it’s part of a larger vascular diagnosis (e.g., central retinal artery occlusion H34.1x) — you may need to code the underlying cause instead.
• Cerebral ischemia (I67.82) is used for chronic cerebral ischemia; acute cerebrovascular ischemia without infarction may map to TIA (G45.9) or other I60-I67 codes.
• N28.0 covers both ischemia and infarction of the kidney — no separate code exists for renal infarction alone.
• CPT codes for ischemia are procedure/intervention-based (e.g., revascularization, thrombectomy) and are selected based on the site and method of treatment rather than the ischemia diagnosis itself.

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DERIVATIONS of ischemia

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Query functionality

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Med roots Appendix A Prefixes Appendix B Combining Forms Appendix C Suffixes Appendix D Suffix forms