Category: Critical Care Nursing ScvO2 also helps to detect return of spontaneous circulation (ROSC) rapidly without interruption of chest compressions, because ROSC will result in a rapid increase in ScvO2 as oxygen delivery to tissues dramatically increases.
Category: Critical Care Nursing ScvO2 values normally range from 60% to 80%. During cardiac arrest and CPR, these values range from 25% to 35%, indicating greatly enhanced oxygen extraction of tissues owing to the inadequacy of oxygen delivery during CPR.
Category: Critical Care Nursing Central venous oxygen saturation, ScvO2, can be used to monitor resuscitative measures. The mixed venous blood oxygen saturation in the pulmonary artery (SvO2) represents the oxygen remaining in the blood after systemic extraction.
Category: Critical Care Nursing PETCO2 monitoring is valuable in patients after return of spontaneous circulation to monitor endotracheal tube placement, titrate minute ventilation to avoid hyperventilation and detect sudden hemodynamic deterioration.
Category: Critical Care Nursing Return of spontaneous circulation (ROSC) causes immediate and significant increases in PETCO2. Therefore, PETCO2 monitoring can detect ROSC at any time during the chest compression cycle, providing valuable guidance.
Category: Critical Care Nursing PETCO2 monitoring also can aid in the diagnosis and treatment of PEA. Patients in a state of PEA with mechanical heart activity may have pulsatile flow that simply cannot be detected by palpation of a pulse.
Category: Critical Care Nursing Resuscitation after cardiac arrest is likely to fail if PETCO2 values of 10 mm Hg or more are not achieved. Therefore, values less than 10 mm Hg should prompt the clinician to enhance the quality of CPR.
Category: Critical Care Nursing PETCO2 depends on CO2 production, alveolar ventilation, and pulmonary blood flow (ie, cardiac output) and correlates well with coronary perfusion pressure and cerebral perfusion pressure during CPR.
Category: Critical Care Nursing The partial pressure of CO2 in exhaled air at the end of expiration (PETCO2) can be a reliable indicator of cardiac output during CPR. This is most reliably measured through waveform capnography after endotracheal intubation.
Category: Critical Care Nursing Electrocardiographic monitoring during cardiac arrest indicates the presence or absence of electrical but not mechanical activity. It also does not provide reliable information regarding the effectiveness of CPR.
Category: Critical Care Nursing Dependent lividity and rigor mortis develop after hours of cardiac arrest. Temperature is an unreliable predictor of duration of cardiac arrest because it does not decrease significantly during the first hours of arrest.
Category: Critical Care Nursing After the initial minutes of cardiac arrest, the physical examination may provide little evidence of the duration of arrest. Pupils dilate within 1 minute but constrict if CPR is initiated immediately and performed effectively.
Category: Critical Care Nursing Primary respiratory arrest results in transient tachycardia followed by hypertension due to mounting hypoxia, then a loss of consciousness, with tachycardia then transitioning to bradycardia and finally, pulselessness occurs.
Category: Critical Care Nursing With sudden onset of cardiac arrest, as in ventricular fibrillation, loss of consciousness occurs within 15 seconds, although agonal gasping respirations may persist for several minutes.
Category: Critical Care Nursing Cardiopulmonary arrest is defined by the triad of unconsciousness, apnea and pulselessness. The pulse is palpated in a large artery (carotid or femoral). If any question exists about the diagnosis of pulselessness, CPR should be initiated.
