Critical Care: SIRS, MODS, Anaphylactic Shock, TBI, and Stroke

Comprehensive vocabulary flashcards covering the pathophysiology, clinical staging, diagnostics, and management of SIRS, MODS, Anaphylactic Shock, Traumatic Brain Injury, and Cerebrovascular Accidents.

Systemic Inflammatory Response Syndrome (SIRS)

A systemic inflammatory response to a variety of severe insults (such as tissue trauma, burns, ischemia, or infection), characterized by generalized inflammation in organs remote from the initial insult.

Multiple Organ Dysfunction Syndrome (MODS)

The failure of two or more organ systems in an acutely ill patient such that homeostasis cannot be maintained without medical intervention, with mortality rates rising linearly with the number of failed systems.

Primary MODS

A classification of multiple organ dysfunction syndrome that occurs as a direct result of initial tissue injury, trauma, or ischemia causing impaired local perfusion.

Secondary MODS

A classification of multiple organ dysfunction syndrome that arises insidiously over approximately one month as a complication of SIRS and sepsis rather than direct primary trauma.

Stage 1 MODS

The initial stage of MODS characterized by increased volume requirements, mild respiratory alkalosis accompanied by oliguria, hyperglycemia, and increased insulin requirements.

Stage 2 MODS

The second stage of MODS characterized by tachypnea, hypocapnia, hypoxemia, moderate liver dysfunction, and potential hematologic abnormalities.

Stage 3 MODS

The third stage of MODS characterized by shock, elevated BUN and creatinine levels, acid-base disturbances, and significant coagulation abnormalities.

Stage 4 MODS

The fourth stage of MODS characterized by vasopressor dependence, decreased urine output (oliguria), ischemic colitis, and severe lactic acidosis.

Hyperlacticacidemia

An excess of lactic acid in the bloodstream occurring during the hypermetabolic state of progressive shock, SIRS, and MODS.

Anaphylaxis

A life-threatening, immediate allergic response occurring in sensitized individuals within seconds to minutes following exposure to a specific antigen.

Anaphylactic Shock

A fatal consequence of anaphylaxis characterized by widespread vascular collapse, systemic vasodilation, a precipitous drop in blood pressure, and progression to multiorgan failure.

Type 1 (Immediate) Hypersensitivity

An immune mechanism involving the production of IgE antibodies that bind to mast cells via $Fc\epsilon RI$ receptors, triggering the immediate degranulation of vasoactive amines and cytokines upon antigen re-exposure.

Serum Tryptase Level

A diagnostic laboratory test used to confirm mast cell activation in systemic allergic reactions, showing elevated levels within $4\,\text{hours}$ of an event.

Alpha-1 ($\alpha_1$) Adrenergic Receptor

Adrenergic receptor whose stimulation increases vasoconstriction and systemic vascular resistance, elevates blood pressure, and decreases mucosal edema in the airways.

Beta-1 ($\beta_1$) Adrenergic Receptor

Adrenergic receptor whose stimulation increases cardiac contraction force and elevates heart rate.

Beta-2 ($\beta_2$) Adrenergic Receptor

Adrenergic receptor whose stimulation promotes bronchodilation and decreases the release of inflammatory mediators from mast cells.

Traumatic Brain Injury (TBI)

An insult to the brain producing intellectual, emotional, social, and vocational changes, in which $30\%$ of cases are fatal and $20\%$ die of secondary brain injury.

Secondary Brain Injury

Evolving damage to neural tissue following primary head trauma, caused by cerebral ischemia from hypoxia and hypotension, secondary hemorrhage, and cerebral edema.

Coup-Contrecoup Injury

A complex head injury mechanism consisting of an initial focal impact point ('coup') followed by rebound injury of the cranial contents on the opposite side of the skull ('contrecoup').

Linear Skull Fracture

A cranial fracture appearing as thin lines on an X-ray that does not involve bone displacement and typically requires no medical treatment.

Basilar Skull Fracture

A fracture occurring in the bones over the base of the frontal and temporal lobes, clinically marked by blood or CSF leakage from the ears or nose, periorbital ecchymosis ('raccoon eyes'), and Battle's sign.

Diffuse Axonal Injury (DAI)

The most severe form of closed head trauma, involving widespread shearing damage across the entire brain tissue at the microscopic level without a focal, surgically removable lesion.

Epidural Hematoma

A focal intracranial hemorrhage forming in the extradural space between the inner table of the skull and the dura mater.

Subdural Hematoma

A focal collection of blood accumulating within the subdural space located between the dura mater and arachnoid membrane.

Intracerebral Hematoma

A focal intracranial hemorrhage caused by bleeding directly into the neural parenchyma of the brain tissue itself.

Cerebrovascular Accident (CVA)

Also called a stroke or 'brain attack,' a clinical condition where a portion of the brain is damaged due to a sudden interruption or lack of blood supply.

Thrombotic Stroke

An ischemic stroke subtype caused by occlusion of a cerebral artery due to the formation of a localized blood clot (thrombus) over an atherosclerotic plaque.

Embolic Stroke

An ischemic stroke subtype caused by an embolus originating outside the cerebral circulation (such as a cardiac clot from atrial fibrillation) that detaches and occludes a cerebral artery.

Transient Ischemic Attack (TIA)

A temporary episode of focal neurological dysfunction lasting minutes to hours without radiographic evidence of acute infarction on CT or MRI, serving as a critical warning sign for future stroke.

Intracerebral Hemorrhage (ICH)

A hemorrhagic stroke subtype most frequently provoked by chronic arterial hypertension that ruptures vessels and causes bleeding directly into brain tissue, elevating local pressure.

Subarachnoid Hemorrhage (SAH)

A hemorrhagic stroke subtype occurring when a blood vessel (most commonly an aneurysm) ruptures, rapidly filling the subarachnoid space surrounding the brain with blood.

Cincinnati Prehospital Stroke Scale (CPSS)

A three-item prehospital evaluation derived from the NIHSS that screens for facial droop, arm drift, and abnormal speech to rapidly identify potential stroke.

National Institutes of Health Stroke Scale (NIHSS)

An 11-item clinical scoring tool with cumulative scores from $0$ to $42$ used by healthcare professionals to objectively quantify functional neurological impairment in stroke patients.

Glasgow Coma Scale (GCS)

A standardized neurological scale measuring eye-opening ($1\text{--}4$), verbal response ($1\text{--}5$), and motor response ($1\text{--}6$) to objectively grade conscious state on a scale from $3$ to $15$.

Tissue Plasminogen Activator (tPA)

Recombinant alteplase, an intravenous thrombolytic agent administered ideally within $3\text{--}4.5\,\text{hours}$ of ischemic stroke onset to dissolve occlusive clots and restore cerebral blood flow.

Broca's Area

A motor speech area in the frontal lobe of the brain that coordinates the muscles of the larynx, pharynx, and mouth to produce spoken language.

Wernicke's Area

A cortical speech center in the temporal/parietal region of the brain responsible for understanding and comprehending written and spoken language.

Aneurysm Coiling

A minimally invasive endovascular procedure wherein tiny detachable metal coils are guided via a catheter into a cerebral aneurysm to induce clotting, block blood entry, and prevent rupture.

Constraint-Induced Therapy

A post-stroke rehabilitative motor therapy (also called forced-use therapy) in which an unaffected extremity is restrained to compel repetitive functional use and neuroplastic recovery of the paretic limb.