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Context: Ultrasound-guided bilateral superficial cervical plexus block (BSCPB) is a technique described for thyroid surgeries for postoperative analgesia as the surgery can cause severe pain and discomfort. Perineural dexamethasone is known to prolong analgesic duration and reduce postoperative nausea/vomiting. Aims: To assess the efficacy of dexamethasone as an adjuvant to BSCPB with 0.25% bupivacaine on isoflurane consumption, intraoperative hemodynamic parameters, and postoperative analgesia in patients undergoing thyroid surgeries under general anesthesia. Settings and Design: This was a randomized control trial. Subjects and Methods: Eighty patients were randomized to two equal groups using random number table into Group A with BSCPB receiving 20 mL of 0.25% bupivacaine and Group B with BSCPB receiving 19 mL of 0.25% bupivacaine + injection dexamethasone 4 mg in the preinduction period. Hemodynamic parameters, isoflurane consumption, postoperative visual analog scale (VAS) score, and antiemetic effect over 24 h were compared between two groups. Statistical Analysis Used: Microsoft excel data sheet, Chi-square test, and independent t-test were used for statistical analysis. Results: The intraoperative hemodynamic parameters were comparable between the two groups. There was a significant difference in mean VAS score between two groups from 6 h to 20 h postoperatively. The time of rescue analgesic in Group A was 7.09 ± 1.04 min and Group was 13.19 ± 1.46 min with P < 0.0001. In Group A, 40% had nausea and 35% had vomiting, and in Group B, 7.5% had nausea and 5% had vomiting. Conclusions: Preinduction ultrasound-guided BSCPB with bupivacaine and dexamethasone provides longer duration of postoperative analgesia and lesser nausea and vomiting compared to bupivacaine alone.
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Background and Aims: Changes in the sympathetic nervous system by pain can impact smooth muscle tone and can alter perfusion. This can be monitored by perfusion index (PI). It is a non-invasive, indirect, and continuous measure of peripheral perfusion. This study investigates the changes in PI due to painful stimuli under general anaesthesia. Methods: Twenty patients between the ages of 20 and 45 years, with informed consent, who were undergoing elective laparoscopic procedure, and belonging to the American Society of Anesthesiologists (ASA) physical status class I were connected with standard monitors along with SEDLINE, pulse oximetry (Root, Masimo Corporation®, Irvine, CA, USA) to monitor PI and Pleth-Variability Index (PVi). General anaesthesia was administered. PI, PVi, heart rate (HR), and non-invasive blood pressure were recorded pre-induction, during induction, before and after intubation, at the time of pneumoperitoneum (P0), and first laparoscopic port insertion (P1). Later, intravenous injection of fentanyl 0.5 µg/kg was administered and values were recorded at the second (P2) and third (P3) port insertion. The aforementioned parameters were recorded for up to 30 minutes. Statistical confirmation was done through paired t tests. Results: PI values after fentanyl increased from 5.33 ± 2.67 (P1) to 5.99 ± 2.8 (P2) (P < 0.001), and to 6.3 ± 2.88 (P3) (P < 0.001). This increase correlated with a decrease in HR, from 101.42 ± 12.53 (P1) to 87.93 ± 10.98 (P2) (P < 0.001), and to 83 ± 10.82 (P3) (P < 0.001). Conclusion: PI can be a tool to monitor the nociception in anaesthetised patients when administering analgesia.
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Intra-arterial blood pressure measurement is the cornerstone of hemodynamic monitoring in intensive care units (ICU). Accuracy of the measurement is dependent on the dynamic response of the measuring system, defined by its natural frequency (fnatural) and damping coefficient (Zdamping). Gardner's plot (1981) has long been the only way to determine the accuracy of the pressure measurement. Specific objectives: (i) estimation of the amplitude of error in pressure measurement through simulations based on real-world data, (ii) a novel method to correct the error. Simulated blood pressure waveforms of various heart rates were passed through simulated measurement systems with varying fnatural and Zdamping. The numerical errors in systolic and diastolic pressures and mean error in the measured pressure were used to generate heat maps for the various recording conditions, in the same plot as that by Gardner (1981). fnatural and Zdamping from 121 patient recordings are plotted on these heat maps to demonstrate the fraction of unacceptable recordings. Performance of a tunable filter to correct the error is demonstrated. In many clinical settings, the measurement of intra-arterial pressure is prone to significant error. The proposed tunable filter is shown to improve the accuracy of intra-arterial pressure recording.
