Category: Critical Care Nursing Arterial or venous lactate concentration and the base deficit provide accurate assessment of global perfusion status. A lactate concentration greater than 4.0 mM or base deficit more negative than -4 mEq/L indicates circulatory insufficiency.
Category: Critical Care Nursing Neurogenic shock results from interrupted sympathetic and parasympathetic input from the spinal cord to the heart and peripheral vasculature, typically resulting from acute traumatic injury.
Category: Critical Care Nursing Cardiogenic shock results when more than 40% of the myocardium becomes dysfunctional from ischemia, inflammation, toxins or immune injury. Impaired baseline cardiac function can contribute to the development of circulatory shock.
Category: Critical Care Nursing Septic shock often causes three major effects that must be addressed during resuscitation: hypovolemia, cardiovascular depression and induction of systemic inflammation. Septic shock produces hypovolemia, reducing right ventricular filling.
Category: Critical Care Nursing With progressive blood loss, cardiovascular reflexes can no longer sustain adequate filling of the vasculature and frank hypotension supervenes. Arterial hypotension is generally and defined as an arterial BP less than 90 mm Hg.
Category: Critical Care Nursing In hemorrhagic shock, even before the cardiac output declines, blood flow is directed away from noncritical organs/tissues, and their cells produce and release lactic acid. Consequently, acidemia often precedes a decrease in cardiac output.
Category: Critical Care Nursing Hemorrhagic shock results from a rapid reduction in intravascular blood volume. Hemorrhage generally causes an increase in the strength of cardiac contraction and heart rate, followed by baroreceptor activation and peripheral vasoconstriction.
Category: Critical Care Nursing Shock results from the widespread failure of the circulatory system to oxygenate and nourish the body adequately. At the cellular level, shock alters mitochondrial energy transfer and evokes the production and accumulation of toxic chemicals.
Category: Critical Care Nursing The bispectral index (BIS) is used to monitor, analyze and process a patient's electroencephalogram during sedation to produce a number, the BIS score. This number, values from 0 to 100, is used as an indicator of the depth of sedation.
Category: Critical Care Nursing Capnography provides dynamic monitoring of ventilatory status in patients with acute respiratory distress, such as from asthma, bronchiolitis, chronic obstructive pulmonary disease, congestive heart failure and cystic fibrosis.
Category: Critical Care Nursing In addition to uses in resuscitation, capnography can also be used to monitor patients with active seizures and maintain appropriate ETCO2 levels in patients with elevated intracranial pressure.
Category: Critical Care Nursing During cardiac arrest, ETCO2 reflects the degree of pulmonary blood flow as alveolar ventilation and basal metabolism are constant, so that it can be used to gauge effectiveness of cardiopulmonary resuscitation.
Category: Critical Care Nursing Capnography is used in the ED for intubated and nonintubated patients. For intubated patients, it provides information regarding respiratory function and ventilator settings and gives immediate notification of accidental extubation.
Category: Critical Care Nursing Pulse oximeters are generally accurate between 80% and 100% saturation, but large changes in the SpO2 can occur with small changes in the PaO2 in hypoxic patients. Below this range, the role is reversed.
Category: Critical Care Nursing Pulse oximetry measures the percentage of arterial hemoglobin that is in the oxyhemoglobin state. It reflects the amount of oxygen that hemoglobin is carrying as a percent of the maximum it can carry.
