Tissue oximetry in anaesthesia and intensive care

Abstract

Conventional monitoring during surgery and intensive care is not sufficiently sensitive to detect acute changes in vital organs perfusion, while its good quality is critical for maintaining their function. Disturbed vital organ perfusion may lead to the development of postoperative complications, including neurological sequel and renal failure. Nearinfra-red spectroscopy (NIRS) represents one of up-to-date techniques of patient monitoring which is commonly used for the assessment of brain oximetry in thoracic aorta surgery, and -increasingly more often -in open-heart surgery. Algorithms for maintaining adequate brain saturation may result in a decrease of neurological complications and cognitive dysfunction following cardiac surgery. The assessment of kidney and visceral perfusion with tissue oximetry is gaining increasing interest during pediatric cardiac surgery. Attempts at decreasing complications by the use of brain oximetry during carotid endarterectomy, as well as thoracic and abdominal surgery demonstrated conflicting results. In recent years NIRS technique was proposed as a tool for muscle perfusion assessment under short term ischemia and reperfusion, referred to as vascular occlusion test (VOT). This monitoring extension allows for the identification of early disturbances in tissue perfusion. Results of recent studies utilizing VOT suggest that the muscle saturation decrease rate is reduced in septic shock patients, while decreased speed of saturation recovery on reperfusion is related to disturbed microcirculation. Being non-invasive and feasible technique, NIRS offers an improvement of preoperative risk assessment in cardiac surgery and promises more comprehensive intraoperative and ICU patient monitoring allowing for better outcome.

Near‐infrared spectroscopy might be a useful tool for predicting the risk of vascular complications after pediatric liver transplants: Two case reports

“…The parameters that are currently routinely monitored perioperatively, such as electrocardiographic parameters, blood pressure, and SpO 2 , are not able to detect abnormalities in regional blood flow, whereas NIRS can be used to monitor the sequential changes in tissue oxygenation sufficiency in target organs . A previous study demonstrated that rSO 2 levels are not correlated with changes in total serum bilirubin levels .…”

Recent advances in bedside microcirculation assessment in critically ill patients

“…(8) By measuring the oxy- and deoxyhemoglobin fractions, one can calculate StO 2 , the total tissue hemoglobin (THb) and the absolute tissue hemoglobin index (THI); THb and THI are two microcirculatory blood volume indicators. (59,60) The measurements made using NIRS may be affected by the amount of adipose tissue and by the presence of edema at the assessment site. (59,60) The thenar eminence region has been the most used because of the thickness of skin and because the adipose tissue covering this muscle is less affected by body weight variations.…”

“…(59,60) The measurements made using NIRS may be affected by the amount of adipose tissue and by the presence of edema at the assessment site. (59,60) The thenar eminence region has been the most used because of the thickness of skin and because the adipose tissue covering this muscle is less affected by body weight variations. (59,60) …”

“…(59,60) The thenar eminence region has been the most used because of the thickness of skin and because the adipose tissue covering this muscle is less affected by body weight variations. (59,60) …”

Managerial Decision-making for Daily Case Allocation Scheduling and the Impact on Perioperative Quality Assurance

“…Finally, the surgical procedures themselves are physiologic stressors, even with anesthesia. (3)(4)(5) These complicating conditions always challenge the anesthesia providers in terms of maintaining risk-reduction strategies, comprehensive analysis abilities, and performing emergency procedures. In part, anesthesia-related mortality is declining due to advances in monitoring technology, establishment and application of anesthesia regulations, and implementation of systematic measures to reduce human error.…”