Question

List 10 different diagnostic tests used to diagnose alterations in central and tissue perfusion. Explain what each test is and how it gives you information about perfusion status.

Answer 1

Ans) Transcutaneous oximetry (TcPO2) is one such tool to assess angiosome specific perfusion. The TcPO2 measures the oxygen tension 1 to 2 mm deep in the skin from the local capillary perfusion. A value > 70 mmHg is normal while < 40 mmHg predicts impaired wound healing and < 30 mmHg is critical limb ischemia.

- MonitoringMonitoring of tissue perfusion includes biomarkers of global tissue perfusion, measures for assessment of perfusion in non-vital organs, and direct visualization of sublingual microcirculation.

- Three main clinical implications for perfusion indices were reported. First, the presence of poor tissue perfusion in a shocked patient is usually associated with worse outcome. Second, persistently impaired perfusion despite adequate resuscitation is associated with worse outcome. Third, normalization of some perfusion indices (lactate and central venous oxygen saturation) has become one of the resuscitation targets in patients with septic shock.

- Direct visualization of sublingual circulation represents a promising tool for evaluation of peripheral perfusion. Simple and user-friendly protocols are being introduced to facilitate the use of sublingual circulation as a bedside tool for assessment of shocked patients.

- Although the collective evidence shows the clear relation between impaired peripheral perfusion and mortality, the use of different perfusion indices as a resuscitation target was not adequately investigated. Most of the data concerning the perfusion indices are extracted from observational trials with a few number of randomized controlled trials.