Injury to the Submandibular Duct and Secondary Fibrosis Causing Sialocele: An Unusual Complication of Submental Intubation.

Maxillofacial fractures with the nasal/skull base fractures may preclude nasotracheal intubation, and oro-tracheal intubation may obstruct surgical access. In these cases, submental intubation is a safe and well-accepted alternative, associated with low morbidity and complication rate. We report a case of one such rare complication, wherein following submental intubation, the patient presented with a sublingual sialocele, associated with dilatation of the submandibular duct with surrounding fibrosis. The secondary sublingual sialocele we encountered could have been due to errors in the technique of submental intubation. Hence, thorough knowledge of the submental and submandibular region's anatomy is important to avoid complications.

Ultrasound-guided erector spinae plane block for awake spine surgery: A case report and review of the literature.

Percutaneous endoscopic lumbar discectomy is increasingly gaining recognition as an alternative to open microdiscectomy for the treatment of intervertebral disk herniation. Apart from the neuraxial blockade, and general anesthesia, there is literature demonstrating the performance of endoscopic lumbar discectomy under sole local anesthesia infiltration. This is particularly advantageous as an awake patient assists the surgeon by verbalizing and preventing any inadvertent nerve root damage. However, marked pain has been reported during key steps such as endoscope port installation and radiculolysis. The erector spinae plane (ESP) block is an interfascial paraspinal block that soaks the spinal nerve roots with epidural spread providing superior analgesia for endoscopic discectomy. The utility of ESP block as a perioperative analgesic technique following spine surgery is well established; there are no reports of successful endoscopic discectomy performed using this block. This article emphasizes the utility of ESP block as the sole anesthetic technique for minimally invasive spine surgery in the awake state.

Effect of duration of pneumoperitoneum on renal function in patients undergoing laparoscopic surgeries: a prospective observational study.

This study aimed to assess the effect of pneumoperitoneum and, thereby, raised intra-abdominal pressure for different durations (≤ 1 h, 1-3 h and > 3 h) on renal function. One hundred and twenty adult patients were allocated to four groups-the Control Group A (N = 30; patients undergoing non-laparoscopic surgery) or Group B (N = 30; patients undergoing laparoscopic surgery with duration of pneumoperitoneum < 1 h) or Group C (N = 30; patients undergoing laparoscopic surgery with duration of pneumoperitoneum 1-3 h) or Group D (N = 30; patients undergoing laparoscopic surgery with duration of pneumoperitoneum > 3 h). The baseline, intraoperative (at the end of pneumoperitoneum/surgery), and postoperative (after 6 h) values of blood urea levels, creatinine clearance, and serum cystatin C were compared. The results showed that the raised IAP (10-12 mmHg) and varying durations of pneumoperitoneum (from less than 1 h to more than 3 h) did not significantly affect renal function measured in terms of change in serum cystatin levels from baseline to 6 h in postoperative period. The varying durations of pneumoperitoneum also did not significantly affect serum creatinine or blood urea levels in the postoperative period. CTRI registration: CTRI/2016/10/007334.

The Outcome of Surgically Treated Proximal Femur Fractures Managed by Ortho-anesthetic Geriatric Care Pathway: A Prospective Observational Study with 2-Year Follow-Up.

Background: Evaluation of the ortho-anesthetic geriatric care pathway for patients with proximal femur fracture in a tertiary care referral center was done by reporting the peri-operative morbidity and mortality. Clinical and demographic predictors of mortality were also identified in this cohort. Material and Methods: This prospective observational study was conducted between August 2017 and November 2018. Demographic, anesthetic and surgical characteristics were recorded. Telephonic post-discharge follow-up was done for a period of 2 years. Factors predicting mortality were estimated using multivariate logistic regression. Results: The cohort was characterized by frailty, high ASA physical status, NYHA class and Charlson co-morbidity index. The delay in presentation to hospital and subsequent surgical fixation was 7 (1-8) and 8 (5-13) days, respectively. The 30, 60, 90-day, 1-year and 2-year mortality was 13.6%, 21.8%, 25.45%, 36.5% and 44%, respectively. Intra-operative blood transfusion was a predictor of 30-day mortality (OR 9.2, 95% CI 1.02-83.17; p = 0.048). Pre-operative respiratory dysfunction predicted 60-day (OR 11.245, 95% CI 1.38-91.58; p = 0.024) and 90-day (OR 11.654, 95% CI 1.91-71.1; p = 0.008) mortality. Post-operative morbidity was reported in 31 (28.1%) patients; incidence of pneumonia (n = 9), sepsis (n = 8), MI (n = 6), PTE (n = 5) and ARF (n = 3) were 8.18%, 7.27%, 5.45%, 4.54% and 2.72%, respectively. Conclusion: Existing pathway facilitated surgical fixation with median delay of 8 days which should be shortened to 48 h. High mortality in our cohort needs to be decreased by preventing admission delays and aggressively managing co-morbidities. Acceptable benchmark goals for pre-operative optimization of lung disease and decrease in intra-operative blood transfusion need to be incorporated in existing care pathway.

A Prospective, Randomized Comparison of the Classical Altemir's Method With the Newer Seldinger's Technique of Submental Intubation.

BACKGROUND: Submental intubation performed using the classical Altemir's technique is a well-accepted, safe technique for providing optimal operating field to the maxillofacial surgeon, in cases where either nasotracheal or orotracheal intubation is impossible. We propose a new, percutaneous Seldinger's technique of submental intubation as an interesting alternative to the classical Altemir's technique, wherein a percutaneous dilatational tracheostomy kit is used to dilate the submental tract, instead of bluntly dissecting it. We hypothesized that Seldinger's technique would be associated with reduced procedure time and minimal scar formation in patients with maxillofacial fractures. METHODS: We enrolled 60 patients scheduled to undergo maxillofacial injury fixation under general anesthesia. After consent, the cohort was randomly allocated to undergo submental intubation by either the classical Altemir's technique or Seldinger's technique. As our primary objective, we noted the time taken to complete the procedure of submental intubation. Our secondary objectives were the components of primary outcome, such as disconnection/apnea time, bleeding, and technical difficulties during the procedure. We also observed for complications such as presence of salivary fistula/infection at hospital discharge and scar characteristics at 1- and 3-month follow-up. RESULTS: The median time for performing submental intubation in the Seldinger group was significantly lower than that in the Altemir group (170.5 [136.5-256.0] seconds vs 220.0 [205.5-289.0] seconds; P value, .040). The median disconnection time was also significantly lower in the Seldinger group (12.0 [10.8-20.0] seconds vs 19.0 [15.0-23.0] seconds; P value, .036). Furthermore, significant bleeding was absent in nearly 53.8% of the study participants in the Seldinger group as compared to 25.9% in the Altemir group. At follow-up, there was no evidence of differences in scar characteristics between the 2 groups. CONCLUSIONS: Seldinger's technique is associated with shorter procedure time and reduced apnea time due to easier and better tract formation, thus minimizing the effort required to exteriorize the endotracheal tube. Furthermore, as dilation reduces tissue damage, Seldinger's technique is associated with significantly less procedural bleeding. Thus, Seldinger's technique can be safe, easy, and faster to perform compared with the classical Altemir's technique of submental intubation in patients with maxillofacial trauma.

Recent advances in critical care: Part II.

With the increasing number of critically ill patients being admitted to intensive care units (ICUs), newer techniques and treatment modalities continue to evolve for their adequate management. Thus, it has become imperative to understand existing tools and resources, and utilise or repurpose them to achieve better results that can decrease morbidity and mortality. In this writeup, we chose five areas of interest, including analgosedation, role of colloids, recent advancements in the management of respiratory failure, the role of extracorporeal membrane oxygenation, and newer antimicrobials. The role of analgosedation in the critically ill has gained importance with focus on post-ICU syndromes, and albumin has re-entered the fray as a possible repairer of the injured glycocalyx. The coronavirus disease 2019 (COVID-19) pandemic forced us to relook at various ventilator strategies and mechanical support for the failing circulation has now become more common with clear end-points. Rising microbial antibiotic resistance has opened up the research on newer antibiotics.

Ketofol as an Anesthetic Agent in Patients With Isolated Moderate to Severe Traumatic Brain Injury: A Prospective, Randomized Double-blind Controlled Trial.

BACKGROUND: The effects of ketofol (propofol and ketamine admixture) on systemic hemodynamics and outcomes in patients undergoing emergency decompressive craniectomy for traumatic brain injury (TBI) are unknown and explored in this study. METHODS: Fifty patients with moderate/severe TBI were randomized to receive ketofol (n=25) or propofol (n=25) for induction and maintenance of anesthesia during TBI surgery. Intraoperative hemodynamic stability was assessed by continuous measurement of mean arterial pressure (MAP) and need for rescue interventions to maintain MAP within 20% of baseline. Brain relaxation scores, serum biomarker-glial fibrillary acidic protein levels, and extended Glasgow Outcome Scale (GOSE) at 30 and 90 days after discharge were also explored. RESULTS: MAP was lower and hemodynamic fluctuations more frequent in patients receiving propofol compared with those receiving ketofol (P<0.05). MAP fell >20% below baseline in 22 (88%) patients receiving propofol and in 10 (40%) receiving ketofol (P=0.001), with a greater requirement for vasopressors (80% vs. 24%, respectively; P=0.02). Intraoperative brain relaxation scores and GOSE at 30 and 90 day were similar between groups. Glial fibrillary acidic protein was lower in the ketofol group (3.31±0.43 ng/mL) as compared with the propofol (3.41±0.17 ng/mL; P=0.01) group on the third postoperative day. CONCLUSION: Compared with propofol, ketofol for induction and maintenance of anesthesia during decompressive surgery in patients with moderate/severe TBI was associated with improved hemodynamic stability, lower vasopressor requirement, and similar brain relaxation.

Incidence of Interstitial Alveolar Syndrome on Point-of-Care Lung Ultrasonography in Pre-eclamptic Women With Severe Features: A Prospective Observational Study.

BACKGROUND: Lung interstitial edema is a clinically silent pathology that develops before overt pulmonary edema among pre-eclamptic women with severe features. Point-of-care lung ultrasonography (LUS) has been suggested as an accessible bedside tool that may identify lung interstitial edema before developing clinical signs and symptoms. Thus, we planned to use bedside LUS as a diagnostic tool in admitted pre-eclamptic women with severe features, with the aim of identifying alveolar-interstitial fluid, seen as B-lines. Our primary objective was to assess the incidence of interstitial alveolar syndrome on lung ultrasonography. METHODS: We conducted a prospective, single-center, observational study on parturients with pre-eclampsia with severe features over a period of 15 months. LUS in 4 intercostal spaces (ICS) was performed on all eligible patients. The number of single or confluent B-lines in each space was recorded by an independent observer. A scoring system was used to grade the lung fluid content based on the number of single and confluent B-lines per ICS, with scores ranging from 0 to 32 (low, 0-10; moderate, 11-20; and high, 21+). The incidence of B-lines at admission and before and after delivery was calculated. In addition, bedside 2D echocardiography was performed to assess left ventricular systolic and diastolic function. Any correlation between presence of B-lines on LUS and blood pressure, clinical symptoms, or echocardiography findings was assessed. RESULTS: Seventy patients were enrolled in the study. On LUS, B-lines were seen in 64.3% patients at admission (45/70 vs 25/70 without B-lines; P = .02), 65.7% patients before delivery (46/70 vs 24/70 without B-lines; P = .01), and 58.6% patients 24 hours postpartum (41/70 versus 29/70 without B-lines; P = .15). Nearly all patients (94.3%) exhibited low to moderate severity of pulmonary fluid burden at admission. Echocardiography revealed diastolic dysfunction in 47.1% (n = 33/70) patients with associated B-lines in the majority (n = 32/33). The total B-line score and E/e' ratio among patients with diastolic dysfunction was found to be strongly correlated (r = 0.848; P < .001). All pre-eclamptic women with presence of breathlessness (11/11; 100%) and facial puffiness (16/16; 100%) on admission had B-lines on LUS. CONCLUSIONS: We conclude that ultrasonographic pulmonary interstitial syndrome is present in more than half of the women with pre-eclampsia with severe features and correlates with diastolic dysfunction, high blood pressure records, and acute-onset breathlessness.

Validation of Hindi version of the obstetric quality of recovery score-11 (ObsQoR-11 H) following elective caesarean section.

Background and Aims: Obstetric quality of recovery score-11 (ObsQoR-11) was developed in English to evaluate the quality of recovery in the caesarean section. We aimed to validate the Hindi version of ObsQoR-11 (ObsQoR-11H) for Hindi-speaking patients to evaluate the quality of recovery following the elective caesarean section. Methods: The ObsQoR-11 was translated into Hindi and assessed for validity, acceptability and feasibility. The questionnaire was administered postoperatively at 24 and 48 hours, and the Global Health Numeric Rating Scale (NRS) was used to evaluate recovery. Results: The mean (standard deviation [SD]) (95% confidence interval [CI]) ObsQoR-11 H was 75.94 (4.09)(95% CI 75.1, 76.7) and 80.25 (4.08)(95% CI 79.5, 81) at 24 and 48 hours, respectively. The mean (SD) (95%CI) Global Health NRS scores were 71.22 (5.97)(95% CI 70, 72.4) and 77.37 (5.79)(95% CI 76.2, 78.5) at 24 and 48 hours, respectively. Convergent validity showed a strong correlation between ObsQoR-11H and Global Health NRS (Spearman's correlation coefficient [rs] >0.8 and 0.78) scores at 24 and 48 hours, respectively. Discriminant validity was significant in appreciating the difference between good and poor recovery (P < 0.001). Split-half coefficient of 0.69 and 0.65 and Cronbach's alpha (α) of 0.91 and 0.82 at 24 and 48 hours suggested good score reliability. The acceptability and feasibility of the score were also good. Conclusion: The ObsQoR-11H discriminated well between 'good' and 'poor' recovery and correlated strongly with Global Health NRS scores. It was found to be a valid, reliable, acceptable and feasible tool for psychometric recovery evaluation after elective caesarean section in Hindi-speaking women.

Prone cardiopulmonary resuscitation: Relevance in current times.

The most common and recommended position for performing cardiopulmonary resuscitation (CPR) is the supine position. However, clinicians may encounter situations when patients suffer cardiac arrest in prone position. Prone CPR has been described previously in a number of settings, most commonly intraoperative. In the current COVID-19 era, with more patients being nursed in prone position, an increase in the incidence of cardiac arrests requiring prone CPR is expected. Hence most of the resuscitation guidelines have made prone CPR a vital component of their recommendations. To date, most of our health-care workers have limited knowledge about prone resuscitation and the literature surrounding it. Nonetheless, with the current evidence at hand, it seems to be a reliable method of providing resuscitation and all health-care workers should be well versed with it. Thus, the goal of this narrative review is to try and fill the gaps in our knowledge about prone CPR. Literature search was done on PubMed, Medline, EMBASE using keywords 'CPR', 'Resuscitation', 'Prone Position', 'Prone', 'Prone CPR'.

Opioid sparing strategies for perioperative pain management other than regional anaesthesia: A narrative review.

Opioids play a crucial role in pain management in spite of causing increased hospital morbidity and related costs. It may also cause significant risks such as postoperative nausea and vomiting (PONV), sedation, sleep disturbances, urinary retention and respiratory depression (commonly referred to as opioid related adverse effects) in postoperative patients. In order to evade these opioid related side effects and also improve pain management, multimodal analgesia i.e., combination of different analgesics, was introduced more than a decade ago. Both pharmacological and non-pharmacological techniques are available as opioid sparing analgesia. Research from around the world have proved pharmacological techniques ranging from acetaminophen, NSAIDs (non-steroidal anti-inflammatory drugs), N-methyl-D-aspartate receptor antagonists (NDMA), alpha-2 agonists, anticonvulsants such as gamma aminobutyric acid analogues, beta-blockers, capsaicin, lignocaine infusion to glucocorticoids to be effective. On the other hand, non-pharmacological methods include techniques such as cognitive behavioral therapy, transcutaneous electrical nerve stimulation (TENS), electroanalgesia, acupuncture and hypnosis. However, research regarding the effect of these non-pharmacological techniques on pain management is still needed.

The effect of Bacillus coagulans Unique IS-2 supplementation on plasma amino acid levels and muscle strength in resistance trained males consuming whey protein: a double-blind, placebo-controlled study.

PURPOSE: The aim of the present study was to assess the effect of Bacillus coagulans Unique IS-2 supplementation on absorption and utilization of protein in resistance-trained males. METHODS: In this double blind, placebo-control trial, resistance-trained males (21.08 ± 2.84 years) were randomized to consume, either 20 g of whey protein powder {80% whey protein concentrate (WPC80), amounting to 15.4 g protein} with 2 billion CFU Bacillus coagulans Unique IS-2 (supplemental group) or 20 g of whey protein powder and lactose instead of Bacillus coagulans (placebo group) once daily for 60 days with a controlled resistance exercise protocol. The whey protein concentrate (WPC-80) given to both groups had a lactose content of 6.8%. Plasma-free amino acids (PFAAs) were determined at baseline, at 30 and 60 days of supplementation. Muscle strength, hypertrophy, VO2 max, and body composition, and other biochemical parameters were assessed at baseline and end line. RESULTS: A positive effect of probiotic Bacillus coagulans Unique IS-2 supplementation was observed on protein absorption as evidenced by an increase in total PFAA by + 16.1% (p = 0.004). Branched chain amino acids (BCAA) comprising isoleucine (p = 0.016), leucine (p = 0.001), and valine (p = 0.002) were increased by + 33.1% in ITT analysis as compared to placebo after 60 days. At 30 days an increase in isoleucine by + 35% (p = 0.113), leucine by + 43% (p = 0.032), and valine by + 32% (p = 0.017) was observed in ITT analysis. Probiotic effect was shown on exercise performance as evidenced by an increase in one RM of leg press and vertical jump power by + 16.61% (p = 0.024) and + 7.86% (p = 0.007), respectively. CONCLUSION: Significantly increased absorption of BCAA with supplementation of B. coagulans Unique IS-2 along with whey protein and improvement in leg press and vertical jump power was noted indicating the positive effect of the probiotic on muscle power in the lower body. TRIAL REGISTRATION NUMBER: CTRI/2017/03/008117; Date:16.03.2017.

Fascia iliaca block for hip fractures in the emergency department: meta-analysis with trial sequential analysis.

BACKGROUND: Fascia iliaca block (FICB) has been used to reduce pain and its impact on geriatric patients with hip fractures. OBJECTIVE: We conducted this meta-analysis to investigate the analgesic efficacy of this block in comparison to standard of care (SOC) when performed by non-anesthesiologist in the emergency department. METHODS: Search on PubMed, SCOPUS, EMBASE, Google Scholar and Cochrane database for randomized and quasi-randomized trials were performed. The primary outcome was to compare pain relief at rest at 2-4 h. The pain relief at various time intervals, reduction in opioid use, the incidence of nausea/ vomiting, delirium and length of hospital stay were the secondary outcomes studied. Trial Sequential Analysis (TSA) was performed for the primary outcome. RESULTS: Eleven trials comprising 895 patients were included in the meta-analysis. Patients receiving FICB had significant better pain relief at rest at 2-4 h with mean difference of 1.59 (95% CI, 0.59-2.59, p = 0.002) with I2 = 96%. However, the certainty of the evidence was low and TSA showed that the sample size could not reach the requisite information size. A significant difference in pain relief at rest and on movement started within 30 min and lasted till 4 h of the block. Use of FICB was associated with a significant reduction in post-procedure parenteral opioid consumption, nausea and vomiting and length of hospital stay. CONCLUSIONS: FICB is associated with significant pain relief both at rest and on movement lasting up to 4 h as well as a reduction in opioid requirement and associated nausea and vomiting in geriatric patients with hip fracture. However, the quality of evidence is low and additional trials are necessary.

Limited condylar mobility by ultrasonography predicts difficult direct laryngoscopy in morbidly obese patients: An observational study.

BACKGROUND AND AIMS: Unpredictable difficult laryngoscopy remains a challenge for anaesthesiologists, especially in morbidly obese patients. The present study aimed to determine the efficacy of different sonographic measures as predictors of difficult laryngoscopy in morbidly obese patients undergoing elective surgery. METHODS: This observational study evaluated 70 morbidly obese adult patients (body mass index >35 kg/m2) undergoing elective surgery under general anaesthesia with tracheal intubation. Pre-operative clinical and ultrasonographic variables (anterior condylar translation, tongue thickness, hyomental distance and oral cavity height) associated with difficult direct laryngoscopy ([Cormack Lehane (CL) grade>2]) were analysed. The primary outcome was to determine the efficacy of the above-mentioned sonographic measures as predictors of difficult laryngoscopy (CL grade >2). The secondary outcome compared ultrasonographic predictors with clinical predictors in morbidly obese patients for determining difficult direct laryngoscopy. RESULTS: Amongst the primary outcome measures, limited condylar mobility (anterior condylar translation <9.25 mm) [odds ratio (OR) 0.3, confidence interval (CI):1.04-1.22;P<0.001;area under curve (AUC):0.8] and increased tongue thickness >5.85 cm [OR: 3.2, CI: 1.05-10; P < 0.04; AUC: 0.73] were two independent sonographic predictors for difficult direct laryngoscopy by multivariate logistic regression and receiver operating characteristic curve analyses in morbidly obese patients. The secondary outcome suggested that as compared to clinical predictors such as Mallampati grade and thyromental distance, ultrasonographic variables such as tongue thickness and limited condylar mobility (sensitivity: 56.4%, 70.9%, 66.7% and 93.3%, respectively) better predicted difficult direct laryngoscopy in morbidly obese patients. CONCLUSION: Limited condylar mobility and increased tongue thickness are independent sonographic predictors of difficult direct laryngoscopy in morbidly obese patients.

Containment of varicella outbreak in intensive care unit of a tertiary level hospital.

BACKGROUND: Varicella-Zoster virus (VZV) infection in healthcare organizations, especially in intensive care units (ICU), having admitted immunocompromised patients, is of serious concern as well as poses threat to healthcare workers working in such critical areas. The present report defines the transmission and infection control measures initiated to curtail VZV infection spread in the trauma ICU of a tertiary care hospital of North India. OUTBREAK REPORT: At the infection outset, there were 12 patients admitted in ICU and 54 healthcare workers were posted to manage these critical patients. After confirmation of VZV infection, all susceptible patients as well as healthcare workers were quarantined and fresh intake of patients was restricted. Out of the total healthcare workers, 14 (25.92%) were found susceptible (as per protective VZV IgG titers) and were vaccinated. Of the 12 patients admitted in the ICU, six patients were discharged and sent home directly, four patients expired due to their critical disease state, one patient left against medical advice, and one patient remained admitted in ICU till the incubation period was over. Epidemiologically, line listing for index case reporting was done. The efficacy of control measures was re-evaluated to strengthen existing infection control practices and general measures viz. strict hand washing, adherence to aseptic protocols and intensification of environmental cleaning. CONCLUSIONS: Established varicella surveillance measures ensure VZV outbreaks are identified in a timely manner and control measures implemented to prevent further transmission. Also, vaccination policy among HCWs is the utmost requirement despite having huge financial implications.

A de novo GRIN1 Variant Associated With Myoclonus and Developmental Delay: From Molecular Mechanism to Rescue Pharmacology.

N-Methyl-D-aspartate receptors (NMDARs) are highly expressed in brain and play important roles in neurodevelopment and various neuropathologic conditions. Here, we describe a new phenotype in an individual associated with a novel de novo deleterious variant in GRIN1 (c.1595C>A, p.Pro532His). The clinical phenotype is characterized with developmental encephalopathy, striking stimulus-sensitive myoclonus, and frontal lobe and frontal white matter hypoplasia, with no apparent seizures detected. NMDARs that contained the P532H within the glycine-binding domain of GluN1 with either the GluN2A or GluN2B subunits were evaluated for changes in their pharmacological and biophysical properties, which surprisingly revealed only modest changes in glycine potency but a significant decrease in glutamate potency, an increase in sensitivity to endogenous zinc inhibition, a decrease in response to maximally effective concentrations of agonists, a shortened synaptic-like response time course, a decreased channel open probability, and a reduced receptor cell surface expression. Molecule dynamics simulations suggested that the variant can lead to additional interactions across the dimer interface in the agonist-binding domains, resulting in a more open GluN2 agonist-binding domain cleft, which was also confirmed by single-molecule fluorescence resonance energy transfer measurements. Based on the functional deficits identified, several positive modulators were evaluated to explore potential rescue pharmacology.

Paravertebral block using levobupivacaine or dexmedetomidine-levobupivacaine for analgesia after cholecystectomy: a randomized double-blind trial.

BACKGROUND: Thoracic paravertebral block (TPVB) has emerged as an effective and feasible mode of providing analgesia in laparoscopic cholecystectomy. Though a variety of local anaesthetic combinations are used for providing TPVB, literature is sparse on use of dexmedetomidine in TPVB. We aimed to compare levobupivacaine and levobupivacaine-dexmedetomidine combination in ultrasound guided TPVB in patients undergoing laparoscopic cholecystectomy. METHODOLOGY: 70 ASA I/II patients, aged 18-60 years, scheduled to undergo laparoscopic cholecystectomy under general anaesthesia were enrolled and divided into two groups. Before anaesthesia induction, group A patients received unilateral right sided ultrasound guided TPVB with 15 ml 0.25% levobupivacaine plus 2 ml normal saline while group B patients received unilateral right sided ultrasound guided TPVB with 15 ml 0.25% levobupivacaine plus 2 ml solution containing dexmedetomidine 1 µg.kg-1. Patients were monitored for pain using Numeric Rating Scale (NRS) at rest, on movement, coughing and comfort scores post surgery. Total analgesic consumption in first 48 hour postoperative period, time to first request analgesic and pain scores were recorded. RESULTS: Total amount of rescue analgesia (injection tramadol plus injection tramadol intravenous equivalent dose) consumed during 48 hours postoperatively in group A was 146.55 mg while in group B was 111.30 mg (p = 0.026). Mean time for demanding rescue analgesia was 273 minutes in group A while in group B was 340 minutes (p = 0.00). CONCLUSION: TPVB using dexmedetomidine 1 µg.kg-1 added to levobupivacaine 0.25% in patients undergoing laparoscopic cholecystectomy significantly reduced total analgesic consumption in first 48 hours and provided longer duration of analgesia postoperatively compared to levobupivacaine 0.25% alone.

Single molecule FRET methodology for investigating glutamate receptors.

Single molecule Förster Resonance Energy Transfer (smFRET) allows us to measure variation in distances between donor and acceptor fluorophores attached to a protein, providing the conformational landscape of the protein with respect to this specific distance. smFRET can be performed on freely diffusing molecules or on tethered molecules. Here, we describe the tethered method used to study ionotropic glutamate receptors, which allows us to track the changes in FRET as a function of time, thus providing information on the conformations sampled and kinetics of conformational changes in the millisecond to second time scale. Strategies for attaching fluorophores to the proteins, methods for acquiring and analyzing the smFRET trajectories, and limitations are discussed.