id="ulink_07ae96d5-5458-549e-b614-09b605a7bf3b">Devices and withdrawal of artificial life support
Discontinuation of any medical treatment that is not in line with the patient’s goals of care should occur in a thoughtful fashion with consideration given to promoting comfort and reducing anxiety.
The most commonly performed withdrawal of care within the ICU is the liberation from mechanical ventilation. Though it may seem routine, a well‐established protocol can help facilitate a smooth transition for ventilatory withdrawal. Such a protocol should focus on addressing location of ventilator withdrawal, anticipation and treatment of patient symptoms such as pain and dyspnea, and addressing family anxiety.
Other mechanical life‐sustaining devices should also be considered when discussing withdrawal of care. Mechanical circulatory support devices, pacemakers, and defibrillators fall under this category and should be deactivated if a decision is made to withdraw care. Similar to symptom control after ventilator withdrawal, opioids, anxiolytics, and anticholinergic agents should be provided for patient comfort.
Reading list
1 Angus DC, et al. Use of intensive care at the end of life in the United States: an epidemiologic study. Crit Care Med 2004; 32(3):638–43.
2 Azoulay E, et al. Risk of post‐traumatic stress symptoms in family members of intensive care unit patients. Am J Respir Crit Care Med 2005; 171(9):987–94.
3 Cook D, Rocker G. Dying with dignity in the intensive care unit. N Engl J Med 2014; 370(26):2506–14.
4 Nelson JE, et al. for the Improving Palliative Care in the Intensive Care Unit Project. Models for structuring a clinical initiative to enhance palliative care in the intensive care unit: a report from the IPAL‐ICU Project (Improving Palliative Care in the ICU). Crit Care Med 2010; 38(9):1765–72.
5 O'Mahony S, et al. Preliminary report of the integration of a palliative care team into an intensive care unit. Palliat Med 2010; 24(2):154–65.
6 Swetz KM, Mansel JK. Ethical issues and palliative care in the cardiovascular intensive care unit. Cardiol Clin 2013; 31:657–68.
7 Temel JS, et al. Early palliative care for patients with metastatic non‐small‐cell lung cancer. N Engl J Med 2010; 363:733–42.
Additional material for this chapter can be found online at:
www.wiley.com/go/mayer/mountsinai/criticalcare
This includes multiple choice questions.
PART 2 Cardiovascular Critical Care
Section Editor: Umesh K. Gidwani
CHAPTER 11 Hemodynamic Monitoring
Josue Rivera1 and Leila Hosseinian2
1 North Shore University Hospital, Manhassett, NY, USA
2 Icahn School of Medicine at Mount Sinai, New York, NY, USA
OVERALL BOTTOM LINE
Patients requiring ICU care often require multiple forms of hemodynamic monitoring.
There has been a tremendous increase in usage of invasive hemodynamic monitoring in order to enhance our understanding of patients’ hemodynamics and helping to guide appropriate therapeutic interventions.
Although there is a paucity of evidence to support the use of many of these invasive monitors, they are very commonly used in the ICU.
Arterial lines
Indications
Direct arterial pressure monitoring is recommended for all ICU patients with hemodynamic instability who require inotropic or vasopressor medications as well as significant ventilatory deficits. This allows for continuous monitoring of blood pressure as well as access to the arterial circulation for the measurement of arterial oxygenation and frequent blood sampling.
As the pulse moves peripherally, the pressure waveform is distorted with higher systolic pressure and pulse pressure (Figure 11.1).
Locations for placement
Radial artery: common site of cannulation. Check collateral flow of ulnar artery with the Allen’s test, which has low reliability.
Brachial artery: located in antecubital fossa, lack of collateral circulation, median nerve injury possible.
Axillary artery: can cause axillary nerve damage from hematoma or traumatic cannulation.
Femoral artery: prone to pseudoaneuryms and atheroma formation.
Dorsalis pedis and posterior tibial arteries: most distorted waveforms.
Contraindications
Deficiencies of collateral circulation (e.g. Raynaud’s phenomenon).
Complications
Rates of up to 10%.
Hematoma, bleeding, vasospasm, arterial thrombus, aneurysm, dissection, pseudoaneurysm, infection.
Advanced arterial hemodynamic monitoring
Multiple proprietary systems have developed algorithms for estimating cardiac output from the arterial waveform. Arterial pulse contour analysis can evaluate stroke volume to calculate cardiac output and examine stroke volume variation to assess fluid responsiveness.
Characteristics of the arterial pressure waveform are affected by changes in vascular compliance, aortic impedance, and peripheral arterial resistance, limiting the accuracy and utility of this class of monitors.
Pulse contour analysis
The principle is based on the hypothesis that stroke volume is proportional to the area under the curve of the systolic segment of an arterial waveform.
PiCCO system (Pulsion Medical Systems)
Pulse contour cardiac output (PiCCO) requires the insertion of a central venous catheter and a thermodilution arterial line.
It
