Controversies in the use of the pulmonary artery catheter

Normal Fluctuations in Pulmonary Artery Pressures and Cardiac Output in Patients with Severe Left Ventricular Dysfunction

Background: One barrier to accurate interpretation of changes in hemodynamic pressures and cardiac output is lack of data about what constitutes a normal fluctuation. Few investigators have examined normal fluctuations in these parameters and none have done so in patients with left ventricular dysfunction. Aims: To describe normal fluctuations in pulmonary artery pressures and cardiac output in patients with left ventricular dysfunction. Methods: Hemodynamically stable advanced heart failure patients ( N=39; 55±6 years old; 62% male) with left ventricular dysfunction (mean ejection fraction 22±5%) were studied. Cardiac output and pulmonary artery pressures were measured every 15 min for 2 h. Results: Mean±standard deviation fluctuations were as follows: pulmonary artery systolic pressure=7±4 mmHg; pulmonary artery diastolic pressure=6±3 mmHg; pulmonary capillary wedge pressure=5±3 mmHg; cardiac output=0.7±0.3 l/min. The coefficient of variation for fluctuations in pulmonary artery systolic pressure was 6.7%, in pulmonary artery diastolic pressure was 9.3%, in pulmonary capillary wedge pressure was 9.2%, and in cardiac output was 7.2%. Conclusions: Values that vary <8% for pulmonary artery systolic pressure, <11% for pulmonary artery diastolic pressure, <12% for pulmonary capillary wedge pressure, and <9% for cardiac output from baseline represent normal fluctuations in these parameters in patients with left ventricular dysfunction.

Traumatic brain injury: an integrated clinical case presentation and literature review part II: the continuum of care

The following paper continues the presentation of a case scenario outlining the assessment, interventions and outcome of a person who sustained multiple trauma with a focus on traumatic brain injury (TBI). Part I explored assessment and initial management of the patient from pre-hospital care through to the emergency department and operating theatre. Part II describes the intensive care period as an integral component of the continuum of care. Key issues in the case are presented sequentially with relevant theory integrated and applied to the clinical case throughout the discussion with a focus on the complex physiological, psychological, and spiritual needs of the patient and their family.

The clinical application of pulse contour cardiac output and intrathoracic volume measurements in critically ill patients

Cardiac output (CO) determination by pulmonary artery (PA) catheter has increasingly been criticised within the literature due to its invasive nature and poor correlation between the pressure measurements and intravascular volume status in mechanically ventilated patients. Consequently, alternative less invasive technologies to PA catheterisation are emerging within intensive care. One such novel technology are pulse contour CO (PCCO) systems. They establish comprehensive and continuous haemodynamic monitoring utilising a central venous catheter (CVC) and an arterial line. Furthermore, a key feature of this technology is its ability to produce intrathoracic volume measurements which may provide a better estimation of cardiac preload as well as indicate the presence and severity of pulmonary oedema. This article aims to discuss the theoretical basis and clinical application of PCCO systems, how PCCO systems differ from PA catheters and how the intrathoracic volume measurements are derived. Understanding these advanced concepts will ensure that clinicians are able to employ this innovative monitoring technology more effectively.

Esophageal Doppler monitoring for hemodynamic assessment

This article reviews the importance of hemodynamic monitoring in adding to the clinical assessment of critically ill patients. The esophageal Doppler monitor (EDM) provides a less invasive way of obtaining hemodynamic information quickly and safely at the bedside. The concepts of Doppler signal acquisition and important nursing considerations are reviewed. Case studies are provided to understand how data from the EDM can impact patient care decisions at the bedside.

Hemodynamic Assessment

Hemodynamic monitoring has become an integral component of the assessment of the critically ill. Any technology used for monitoring is a diagnostic tool and only as good as the provider interpreting the data. The article focuses on providing the practitioner the physiologic basis of the hemodynamic profile to cross the chasm of turning data into clinically useful information. Decision-making models are described to facilitate data synthesis and clinical intervention.