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BACKGROUND: Prior data from the isolated forearm technique (IFT) following noxious stimuli suggest that the incidence of response to command may approach 40% under anesthesia 1,2 . We conducted an international, multicenter, pragmatic study of the IFT to establish the incidence of responsiveness following intubation in current practice (NCT02248623). Methods: Following IRB approval at six sites, 260 adult patients were recruited from six centers into a prospective observational cohort study of the IFT during induction of anesthesia . Univariate comparisons were made with Student’s t­test assuming equal variances, and Pearson’s χ2 test. Bivariate models were constructed using logistic regression . RESULTS: The incidence of IFT responsiveness following intubation was 4 .6% (12/260). Responders were younger than nonresponders ([mean±standard deviation] 39±17 vs . 51±16 years old; p=0 .009) and had a higher incidence of observer rated signs of distress (50% vs . 2 .4%; p=0 .027) with 5 out of 12 responders reporting pain through a second hand squeeze . No subject reported explicit recall of intraoperative events when questioned after surgery (n=253) . Depth of anesthesia monitoring values showed a wide range in both groups; however mean values were higher for responders before (53±19 vs . 42±14; p=0 .032) and after (55±24 vs . 43±16; p=0 .032) intubation . In patients not receiving total intravenous anesthesia, exposure to volatile anesthetics prior to intubation reduced the odds of responding (OR 0 .2 (0 .1 - 0 .8); p=0 .022) following adjustment for age . CONCLUSIONS: An incidence rate of 4 .6% suggests that intraoperative connected consciousness may occur frequently but this rate is lower than predicted from previous studies . Larger studies are required to identify risk factors for, and long-term consequences of, IFT responsiveness. REFERENCES: 1 . Sanders RD, Tononi G, Laureys S, Sleigh JW . Unresponsiveness ≠ Unconsciousness Anesthesiology. 2012;116:946­959. 2 . Schneider G, Wagner K, Reeker W, Hanel F, Werner C, Kochs E. Bispectral Index (BIS) may not predict awareness reaction to intubation in surgical patients . J Neurosurg Anesthesiol . Jan 2002;14(1):7-11

Item does not contain fulltext Septic shock is characterised by vasodilation, myocardial depression and impaired microcirculatory blood flow, resulting in redistribution of regional blood flow. Animal and human studies have shown that gastrointestinal mucosal blood flow is impaired in septic shock. This is consistent with abnormalities found in many other microcirculatory vascular beds. Gastrointestinal mucosal microcirculatory perfusion deficits have been associated with gut injury and a decrease in gut barrier function, possibly causing augmentation of systemic inflammation and distant organ dysfunction. A range of techniques have been developed and used to quantify these gastrointestinal perfusion abnormalities. The following techniques have been used to study gastrointestinal perfusion in humans: tonometry, laser Doppler flowmetry, reflectance spectrophotometry, near-infrared spectroscopy, orthogonal polarisation spectral imaging, indocyanine green clearance, hepatic vein catheterisation and measurements of plasma D-lactate. Although these methods share the ability to predict outcome in septic shock patients, it is important to emphasise that the measurement results are not interchangeable. Different techniques measure different elements of gastrointestinal perfusion. Gastric tonometry is currently the most widely used technique because of its non-invasiveness and ease of use. Despite all the recent advances, the usefulness of gastrointestinal perfusion parameters in clinical decision-making is still limited. Treatment strategies specifically aimed at improving gastrointestinal perfuision have failed to actually correct mucosal perfusion abnormalities and hence not shown to improve important clinical endpoints. Current and future treatment strategies for septic shock should be tested for their effects on gastrointestinal perfusion; to further clarify its exact role in patient management, and to prevent therapies detrimental to gastrointestinal perfusion being implemented.