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Hemodynamics in sepsis change as sepsis develops. Initial hemodynamics of sepsis often are much different from later stages of sepsis, shifting from low cardiac output states to high cardiac output states. Tissue oxygenation also changes with initial mixed venous oxyhemoglobin (Svo2) or central venous oxyhemoglobin (Scvo2) levels below normal, with later stages reflecting high values. These changes occur as sepsis progresses, producing a marked disturbance in capillary flow and tissue oxygenation. Treatments for these changes in sepsis are different, making the identification of the hemodynamic state essential to optimally treat the patient. Fortunately, hemodynamic monitoring techniques are markedly improved from older techniques such as the pulmonary artery catheter. With noninvasive techniques such as esophageal and external Doppler for measuring hemodynamics, clinicians beyond the intensive care unit can make hemodynamic assessments that were not possible until just recently. This improved assessment should make it much easier to properly identify sepsis and initiate appropriate treatments in a timely manner. [ABSTRACT FROM AUTHOR]

Critical care practices have evolved to rely more on physical assessments for monitoring cardiac output and evaluating fluid volume status because these assessments are less invasive and more convenient to use than is a pulmonary artery catheter. Despite this trend, level of consciousness, central venous pressure, urine output, heart rate, and blood pressure remain assessments that are slow to be changed, potentially misleading, and often manifested as late indications of decreased cardiac output. The hemodynamic optimization strategy called stroke volume optimization might provide a proactive guide for clinicians to optimize a patient's status before late indications of a worsening condition occur. The evidence supporting use of the stroke volume optimization algorithm to treat hypovolemia is increasing. Many of the cardiac output monitor technologies today measure stroke volume, as well as the parameters that comprise stroke volume: preload, afterload, and contractility., (©2015 American Association of Critical-Care Nurses.)

Changing the perspective of clinical assessment to cellular oxygenation assessment will be a trend in the 1990s, particularly with the development of new technologies. New technologies such as MRI and PET scanning will increase clinicians' ability to assess cellular dysfunction and oxygenation disturbances. Because of improved technology, the focus in assessing oxygenation of the critically ill also will change. Critical care clinicians must accurately identify whether arterial or cellular oxygenation is being assessed. Arterial oxygenation problems are usually a reflection of a loss of hemoglobin or deteriorating lung function (through increased intrapulmonary shunting). Cellular oxygenation problems are more related to the relationship between oxygen delivery and cellular utilization of oxygen. In most critical care situations, cellular oxygenation is the aspect of oxygenation that is of most interest. The more familiar the clinician is with the role oxygen plays in cellular metabolism, the more meaningful the oxygenation assessment becomes. Common nursing techniques for the assessment of oxygenation (eg, physical assessment, blood gases and pulse oximetry) still have a place, but their limited accuracy must be kept in perspective when assessing cellular oxygenation.

The value of airway pressure monitoring is the improved clarity in identifying end-expiration. Short of monitoring intrapleural pressures, airway pressure monitoring has the potential to give the most accurate method for identifying the correct respiratory point to read hemodynamic values. Airway pressure monitoring can improve the reliability of hemodynamic waveform analysis between nurses and reduce some of the subjectivity associated with hemodynamic waveform analysis.