Blood Pressure — NCLEX Review Flashcards

Vocabulary flashcards covering blood pressure basics, components of cardiac output, physiological determinants, measurement techniques, and clinical classifications of hypertension and hypotension.

Blood pressure

A measurement of the amount of pressure exerted by the blood within the circulatory system, measured in $mm\,Hg$ and expressed as systolic over diastolic pressure.

Systole

The contraction phase of the cardiac cycle where blood is driven into the aorta and pulmonary arteries.

Systolic blood pressure

The maximum amount of pressure exerted when the heart contracts and forces blood into the aorta; the top number of the blood pressure reading.

Diastole

The relaxation phase of the cardiac cycle.

Diastolic blood pressure

The minimum amount of pressure exerted when the heart is relaxed; the bottom number of the blood pressure reading.

Cardiac output (CO)

The amount of blood pumped into the circulatory system by the heart within $1\,minute$. ($CO = SV \times HR$).

Stroke volume (SV)

The amount of blood ejected by the ventricle during one heart contraction.

Blood volume

The amount of blood circulating through the body; when decreased (e.g., hemorrhage), blood pressure decreases.

Blood viscosity

The thickness of the blood; increased viscosity increases resistance to flow and blood pressure.

Elasticity

The ability of the vessels to stretch and compress, then return to their original shape.

Peripheral vascular resistance

Describes the ability of the vessels to accommodate increased blood flow without increasing resistance or blood pressure.

Atherosclerosis

Hardening of the arteries that leads to increased vascular resistance and blood pressure.

Contractility

Refers to the heart's ability to contract efficiently; indicated by the ejection fraction.

Ejection fraction

The percentage of blood ejected with each contraction of the ventricles, generally measured in the left ventricle via an echocardiogram.

Preload

The amount of blood inside the ventricles before they contract.

Afterload

The amount of resistance, or constriction, that the heart must overcome to eject blood into the systemic circulation.

Sphygmomanometer

A blood pressure cuff consisting of an inflatable bladder connected to a manometer.

Auscultation

The gold standard for noninvasive blood pressure monitoring using a stethoscope and sphygmomanometer to listen for Korotkoff sounds.

Palpation Method

A technique used to estimate blood pressure by feeling for a pulsatile thrill when Korotkoff sounds are difficult to hear.

Korotkoff sounds

The sounds heard over an artery during cuff deflation; the first sound represents systolic pressure and the disappearance represents diastolic pressure.

White coat syndrome

A phenomenon where a client experience anxiety and a subsequent increase in blood pressure in a health care setting.

Hypertension (Adult)

A blood pressure that is above the expected reference range, generally requiring at least two elevated readings on separate occasions for diagnosis.

Normal Blood Pressure (Adult)

Systolic less than $120\,mm\,Hg$ and Diastolic less than $80\,mm\,Hg$.

Elevated Blood Pressure

Systolic $120$ to $129\,mm\,Hg$ and Diastolic less than $80\,mm\,Hg$.

High blood pressure stage I

Systolic $130$ to $139\,mm\,Hg$ or Diastolic $80$ to $89\,mm\,Hg$.

High blood pressure stage II

Systolic $140\,mm\,Hg$ or higher or Diastolic $90\,mm\,Hg$ or higher.

Hypertensive emergency

Systolic higher than $180\,mm\,Hg$ and/or Diastolic higher than $120\,mm\,Hg$.

Pediatric Hypertension

Blood pressure at or above the $95th$ percentile for age for a child with a healthy BMI on three separate visits.

Hypotension

A blood pressure below the expected range; typically below $90/60\,mm\,Hg$ in an adult without baseline data.

Shock

A life-threatening condition resulting from extreme hypotension, characterized by cold/pale skin, rapid breathing, and a weak/rapid pulse.

Orthostatic hypotension

A drop in systolic pressure of at least $20\,mm\,Hg$ or diastolic pressure of at least $10\,mm\,Hg$ within $1\,min$ of rising to a sitting or standing position.