Why should the anesthesiologist evaluate nutritional status?

BACKGROUND: The anesthesiologist's involvement in perioperative medicine has significantly changed. In order to identify patients at risks of perioperative complications, the anesthesiologist has to consider, amongst others, screening and management of undernutrition. For this purpose knowledge of prevalence and risk factors, along with screening tools and guidelines for an adapted nutritional management and outcomes of renutrition are mandatory. The present review intends to provide these tools to the Anesthesiologists. METHOD: We conduct a literature review in Pubmed, Direct Science and Cochrane Library without limit of time related to undernutrition in the perioperative period. RESULTS: Undernutrition is common in surgical patients. Undernutrition is associated with an increase of morbidity, mortality, length of hospital stay and costs. Undernutrition could probably be detected during the anesthetic consultation with simple and rapid tests, such as SNAQ, MST, MUST and NRS-2002. Nevertheless, further studies are needed to validate such tests in surgical patients. Waiting for these results, we prefer MUST. The implementation of nutritional support recommendations would reduce postoperative complications. CONCLUSION: The anesthesiologist could play an important role in undernutrition screening and its management in order to reduce perioperative morbidity.

In vivo optical spectroscopy monitoring in a new model of muscular compartment syndrome.

BACKGROUND: Muscular compartment syndrome (MCS) is a rare but serious postoperative complication. In vivo optical spectroscopy (INVOS) monitors continuously and non-invasively regional oxygen saturation (rSO(2)), and could predict the development of MCS. METHODS: In 10 healthy volunteers, we inflated a tourniquet to the mean arterial pressure to produce slight venous congestion and arterial hypoperfusion. Comparisons were made between the relative reduction in rSO(2) with baseline (deltaINVOS) and the time to observe motor nerve block (with non-invasive electromyography). Neurological symptoms, pain, and invasive intracompartmental pressure (ICP) were assessed. RESULTS: In the eight volunteers completing the protocol, we observed a profound motor nerve conduction block, immediately reversible. Baseline values were: [mean (sd)] INVOS: 73.3 (8.9)% and ICP: 16.9 (8.6) mm Hg. At the time of the block, values were: INVOS: 46.4 (10.9)%, deltaINVOS: 28.7 (10.6)%, and ICP: 70.0 (5.5) mm Hg. The time to reach the block was 33.0 (10.9) min, and to a deltaINVOS>10%: 27.4 (10.4) min. Receiver-operating characteristic curves demonstrated a similar accuracy of ICP and INVOS to predict the occurrence of the block. Twenty minutes with a deltaINVOS>10% or ICP>30 mm Hg were associated with a sensitivity and a specificity of 95% and 70%; or 91% and 65%, respectively. CONCLUSIONS: We have developed a model of acute immediately reversible MCS. Monitoring using the INVOS technology is as accurate as measurement of ICP, and could be a useful tool to prevent development of intraoperative MCS.