Comparative of the Effectiveness of Different Objective Method for Infraclavicular Brachial Plexus Block Success; Which One of Them is A Reliable and Early Indicator?

ABSTRACT BACKGROUND Traditional methods that evaluate the success of peripheral nerve block have been replaced by methods that allow objective evaluations over time. Multiple objective techniques for peripheral nerve block have been discussed in the literature. OBJECTIVE This study aims to investigate whether perfusion index (PI), non-invasive tissue hemoglobin monitoring (SpHb), tissue oxygen saturation (StO2), tissue hemoglobin index (THI) and body temperature are reliable and objective methods to evaluate the adequacy of infraclavicular blockage. DESIGN A prospective observational study. SETTING Single center, Department of Anesthesiology, Harran University Medical Faculty, Turkey, from February 2019 to December 2019. PATIENTS A total of 100 patients scheduled to undergo forearm surgery. INTERVENTION Ultrasound-guided infraclavicular block (ICB) in 100 patients undergoing forearm surgery. MAIN OUTCOME MEASURES PI, SpHb, StO2, THI and Body Temperature measurements were recorded 5 min before the block procedure, right after the procedure, and until the 25th minute after the procedure at 5-min intervals. These values were compared between the blocked limbs and non-blocked limbs while being statistically compared between the successful and failed block groups. RESULTS Although there were significant differences between the groups of blocked extremity and non-blocked extremity in terms of StO2 (P = 0.001), THI (P = 0.001), PI (P = 0.001) and body temperature (P = 0.001), there was no significant difference between these groups in terms of SpHb (P > 0.05). Moreover, a significant difference was detected between the groups of successful block and failed block in terms of StO2 (P = 0.002), PI (P = 0.002) and body temperature (P = 0.005), while there was no significant difference between these groups in terms of THI (P > 0.05) and SpHb (P > 0.05). CONCLUSION StO2, PI and body temperature measurements are the simple, objective, noninvasive techniques to be used to evaluate success of block procedures. According to The receiver operating characteristic (ROC) analysis, StO2 is the specific parameter with the highest sensitivity among these parameters.

Fully mobile functional brain spectroscopy using near-infrared light and wireless networks

This thesis presents research that creates a mobile solution to monitor human brain functions during real-life activities. The solution utilizes the Internet, the Global Standard for Mobile Communication (GSM) wireless networks, Bluetooth technology, and a number of data protocols. It consists of three main parts: 1. a Bluetooth portable near-infratred light sensor, 2. a personal digital assistant (PDA), and 3. a personal computer (PC). The near real time data acquisition is performed by the sensor while mobility is provided by the GSM PDA. The data is sent over a multi-protocol stack until it reaches the final destination PC. The system provides a light-weight, tissue hemoglobin monitoring system for real-life situations not restricted to a lab.

Fully mobile functional brain spectroscopy using near-infrared light and wireless networks

This thesis presents research that creates a mobile solution to monitor human brain functions during real-life activities. The solution utilizes the Internet, the Global Standard for Mobile Communication (GSM) wireless networks, Bluetooth technology, and a number of data protocols. It consists of three main parts: 1. a Bluetooth portable near-infratred light sensor, 2. a personal digital assistant (PDA), and 3. a personal computer (PC). The near real time data acquisition is performed by the sensor while mobility is provided by the GSM PDA. The data is sent over a multi-protocol stack until it reaches the final destination PC. The system provides a light-weight, tissue hemoglobin monitoring system for real-life situations not restricted to a lab.

Abstract 16044: Measurements of Tissue Oxygen and Hemoglobin on A Near Infra-red Spectroscopy in Emergency Patients With Poor General Conditions

Introduction: In patients with poor general conditions, the conventional pulse oximetry is sometimes unable to determine the oxygen saturation because of peripheral arteriole constriction. The near infra-red spectroscopy (NIRS) can measure absolute concentration of oxygenated, deoxygenated, and total tissue hemoglobin. Purpose: This study aimed to investigate the potential of a novel minimized NIRS system in terms of measurements of tissue oxygen and hemoglobin. Methods: We enrolled 22 normal controls and 83 emergency patients who came to the emergency department with poor general conditions. The tissue oxygen saturation (StO2) and tissue hemoglobin index (T-HbI) on second finger pulp (SFP), thenar eminence (TE), and sternocleid muscle (SM) were measured in both groups. Results: (1) In all subjects including patients with cardio-pulmonary arrest, both the StO2 and T-Hbl values were obtained stably. (2) In the emergency patients, the StO2 value on SFP was lower than those on TE and SM (53% [49-56] vs. 57% [55-60] and 58% [53-62], median [inter-quartile range], p<0.01), whereas those in the normal controls were not different. The StO2 value on SFP was lower in the emergency patients than that in normal controls (60% [58-61], p<0.01). (3) In the emergency patients, the T-Hbl value on SBP was also lower than those on TE and SM (0.13 mM [0.11-0.15] vs. 0.25 [0.22-0.29] and 0.23 [0.18-0.29], p<0.01). The T-HbI value on SFP was also lower in the emergency patients than that in normal controls (0.18 mM [0.17-0.21], p<0.01). Conclusion: NIRS detected peripheral circulatory failure easily and immediately in the emergency patients.

Abstract W MP96: Low Dose Tissue Plasminogen Activator Amplifies Vascular Injury and Worsens Functional Outcomes in Acute Hyperglycemic Stroke Independent of the Model of Reperfusion

Clinically, hyperglycemia (HG) exacerbates reperfusion injury and aggravates tPA-induced hemorrhagic transformation (HT). Yet, most of the experimental hyperglycemic stroke studies exclusively employed suture occlusion model. Only few studies involved tPA in hyperglycemic setting and employed a 10-fold higher dose of tPA than that is used in patients. Thus, in this translational study using suture and thromboembolic occlusion of middle cerebral artery (MCA), with and without human tPA dose, we tested the hypothesis that even acute mild HG worsens the neurovascular injury and functional outcomes irrespective of the method of reperfusion, and that the use of low dose tPA amplifies this injury. Methods: Control and mildly HG rats (140-200 mg/dl, achieved by 30% glucose ip injection 15 min prior to surgery, n=7-9/group) were subjected to MCA occlusion by either suture (90 min) or humanized clot and 24 h reperfusion. tPA (1mg/kg) was injected IV 2 h after induction of ischemia. At 24 h, neurological deficit, infarct size, edema, HT occurrence rate (HT index) and tissue hemoglobin (Hb) were measured. Results: Cerebral blood flow monitoring indicated that % drop at occlusion were similar across the groups and that low dose tPA effectively resolved the clot in the embolic model. tPA did not increase the infarct size in either control or hyperglycemic animals when compared to no tPA groups (Table). HG increased vascular injury (HT index and Hb content) in both suture and embolic occlusion models. The combination of HG and tPA exacerbated the vascular injury and worsened functional outcomes more than each alone. Conclusion: The interaction between HG and even low dose tPA has a significant deleterious effect on cerebrovasculature and functional outcomes independent of the method of reperfusion.