GLOSSARY OF TERMS

AFTERLOAD
involves the physical forces the pump (left ventricle) has to develop to overcome the resistive forces of the vasculature in order to push a bolus of blood (SV) into it during every heart beat

AORTIC
Related to aorta

BIOIMPEDANCE
Electrical resistance of a body segment to a low magnitude, high frequency measurement current.

BODY SURFACE AREA (BSA)
BSA [mSuperscript2], is an estimated (not measured) surface of patient's body.
For adults the approximate value of BSA can be calculated as:
BSA = {[height(cm) + weight(kg)] - 60}/100

BSA
see Body Surface Area

CARDIAC INDEX
Cardiac Index (CI) is an indexed perfusion-significant global blood flow:
CI = CO/BSA. Its dimension is l/min/mSuperscript2

CARDIAC OUTPUT (CO)
CO is the amount of blood the heart pumps in one minute. The resting normal value of CO in all mammals is related to their weight at the rate 0.1 l/min/kg. In order to have only one normal range for patients of different body habitus, its indexed value, called Cardiac Index, is used in hemodynamics.

CARDIODYNAMIC PARAMETERS
are these parameters that do not include a simultaneous processing of blood pressure and blood flow (i.e., hemodynamic parameters)

CHRONOTROPE
a pharmacological agent affecting the heart rate; positive chronotropes increase, negative chronotropes decrease the heart rate.

CI
see Cardiac Index

CO
see Cardiac Output

CONTRACTILITY
is related to the rate of shortening of myocardial fibers in time during mechanical systole, encompassing both the isovolumic and the ejection phase. The isovolumic contractility is affected only by inotropes, the ejection phase contractility is affected both by inotropes and by the effects of intravascular volume (volemia) - i.e., by the Frank-Starling Law.

DIURESIS
reduction of blood volume by pharmacological agents called diuretics

EF
see Ejection Fraction

EJECTION FRACTION [%]
EF is the percentage of blood volume held within the left ventricle at the end of diastole (the End-diastolic Volume, EDV) which is ejected into the vasculature as the Stroke Volume, SV.
EF = 100 (SV/EDV)

EJECTION PHASE CONTRACTILITY INDEX (EPCI)
EPCI = (dZ/dt)max x TFC. The dimension is one/sec. EPCI, directly measured by TEB, represents a normalized combination contribution of a maximum rate of aortic distention (a plethysmographic signal) and a maximum rate of aortic blood velocity increase (a maximum rate of alignment of erythrocytes).

HEART RATE (HR)
HR is the number of heart beats in one minute.

HEMODYNAMICS
deals with simultaneously acquired and processed blood flow and blood pressure.
Hemodynamic state is represented by blood pressure @ blood flow. The per-beat hemodynamically-significant blood pressure is the Mean Arterial Pressure (MAP) and hemodynamically-significant blood flow is Stroke Index (SI). A new hemodynamic state is formed for every heart beat.
Only instrumentation processing simultaneously acquired and processed blood flow and blood pressure can be called hemodynamic instrumentation.

HEMOCONCENTRATION
a supranormal level of Hgb

HEMODILUTION
infranormal level of Hgb; therapy involves transfusion of packed red blood cells

HEMOGLOBIN (Hgb)
Its dimension is gram/deciliter

Hgb
see Hemoglobin

HR
see the Heart Rate

HYPOCHRONOTROPY
inadequate compensatory effect of HR which results in an infranormal value of CI; therapy involves administration of positive chronotropes

HYPODYNAMIC
Infranormal level of SI (for adults: SI < 35 m/mSuperscript2)

HYPOINOTROPY
inadequate level of inotropic state; therapy involves administration of positive inotropes

HYPOTENSION
infranormal value of MAP (for adults: MAP < 70 Torr)

HYPOVOLEMIA
inadequate level of blood volume; therapy involves volume expansion (volume loading)

HYPERCHRONOTROPY
current level of HR produces a supranormal value of CI; therapy involves administration of negative chronotropes

HYPERDYNAMIC
supranormal level of SI (for adults: SI > 65 ml/mSuperscript2)

HYPERINOTROPY
excessive level of inotropic state; therapy involves administration of negative inotropes

HYPERTENSION
supranormal value of MAP (for adults: MAP > 105 Torr)

HYPERVOLEMIA
excessive level of circulating blood volume; therapy involves administration of diuretics

INOTROPIC STATE INDEX (ISI)
ISI = (dSuperscript2Z/dtSuperscript2)max x TFC. The dimension is on1/sec/sec. ISI represents a normalized image of maximum acceleration of aortic blood flow, described in cardiology literature as a parameter affected only by inotropes. ISI is an end-result of the left ventricular impulse, produced at the instant of aortic valve opening by a quadratic rate and magnitude of isovolumic pressure rise.

INOTROPY (INOTROPIC STATE)
is related to a level of pharmacologic agents (inotropes) within blood, affecting the rate of contraction of myocardial fibers. Positive inotropes increase and negative inotropes decrease the myocardial contractility.

INTRAVASCULAR VOLUME
circulating volume of blood involved in therapeutic decisions

LEFT STROKE WORK INDEX (LSWI)
LSWI is a normalized amount of physical work the heart expends over one heart beat interval. Its dimension is g.m/mSuperscript2. LSWI is directly related to myocardial oxygen consumption/beat. Since the majority of oxygen is burned during the isovolumic contraction and the rest during the ejection phase, it also is related to a combined level of myocardial contractility over the entire mechanical systole.

LSWI
se Left Stroke Work Index

MAP
see Mean Arterial Pressure

MEAN ARTERIAL PRESSURE (MAP)
is the value of pressure which would exist at the output node of the heart if there would be no arterial pulsations.
Its approximate value is MAP = {[(Systolic - Diastolic)/3] + Diastolic}.
In HOTMAN™ F11X System MAP is directly measured by the built in NIBP device.

NIBP
Noninvasive Blood Pressure

NONINVASIVE
a technique which does not require a penetration of skin to perform a physiologic measurement

NORMOCHRONOTROPY
a compensatory effect of HR produces CI within a normal range

NORMODYNAMIC
SI within a normal range (35 - 65 ml/mSuperscript2)

NORMOINOTROPY
normal level of inotropic state

NORMOTENSION
MAP within a normal range (70 - 105 Torr)

NORMOVASOACTIVITY
SSVRI within a normal range

NORMOVOLEMIA
normal level of circulating blood volume (does not count the additional blood retained in reservoirs, such as in spleen)

PERFUSION
continuous supply of oxygen through adequate blood flow to the tissues

PRELOAD
involves the inertia forces of inflowing blood into the left atrium during diastole which stretch its fibers, thus storing mechanical energy in them; more stretched fibers (increased preload) contract during systole with a higher force (a mechanically produced an increase in contractility known as the Frank-Starling Law)

PULSE OXIMETRY
a noninvasive technique using a finger clip with optotransmitter and sensor to determine the approximate percentage of erythrocytes in arterial blood which carry oxygen to tissues - see SpOSubscript2

RESPIRATORY RATE (RR)
RR is the number of breaths per minute.

RR
see Respiratory Rate

SaOSubscript2
percentage of oxygenated red blood cells in arterial blood; this parameter is obtained in a blood laboratory from a sample of arterial blood and may be approximated by a continuous measurement of SpOSubscript2

SpOSubscript2
see Pulse Oximetry

SI
see Stroke Index

SSVRI
see Stroke Systemic Vascular Resistance Index

STROKE INDEX (SI)
SI is the indexed volume of blood expelled by the left ventricle over one heart beat interval (i.e. Stroke Volume indexed by BSA)[ml/mSuperscript2].

STROKE SYSTEMIC VASCULAR RESISTANCE INDEX (SSVRI)
SSVRI is a per-beat measure of afterload. Its physical dimension is dyn.sec.cm-5.mSuperscript2, however, in HOTMAN terminology a shorter term called Fluidic Ohm [Fohm], is used.

STROKE VOLUME (SV)
SV is the amount of blood ejected by the left ventricle into the vasculature over one heart beat interval (ml/beat).

TFC
see Thoracic Fluid Conductivity (or Content)

THORACIC
as related to the thorax

THORACIC FLUID CONDUCTIVITY (TFC) [1/ohm]
total conductivity of thorax, representing a conductivity contribution of intravascular, intraalveolar and interstitial compartments; for instance, a supranormal value indicates an excess of fluids within the thoracic cavity, however, cannot pinpoint in which compartment(s) the fluids are.

VASOCONSTRICTION
supranormal value of SSVRI (excessive afterload); therapy involves administration of vasodilators or ACE (Angiotensin Converting Enzyme) Inhibitors.

VASODILATION
infranormal value of SSVRI; therapy involves administration of vasoconstrictors

VOLEMIA
status of circulating intravascular volume (please note that it is not equal to total blood volume)

VOLUME
see Intravascular Volume

VOLUME EXPANSION (VOLUME LOADING)
a therapy instituted to correct detected hypovolemia

VOLUME REDUCTION (DIURESIS)
a therapy instituted to correct detected hypervolemia (volume overload)

Z [ohm]
a commonly used symbol for electrical impedance


earth3