When Is a Bispectral Index of 60 Too Low?: Rational Processed Electroencephalographic Targets Are Dependent on the Sedative-Opioid Ratio

Background: Opioids are commonly used in conjunction with sedative drugs to provide anesthesia. Previous studies have shown that opioids reduce the clinical requirements of sedatives needed to provide adequate anesthesia. Processed electroencephalographic parameters, such as the Bispectral Index (BIS; Aspect Medical Systems, Newton, MA) and Auditory Evoked Potential Index (AAI; Alaris Medical Systems, San Diego, CA), can be used intraoperatively to assess the depth of sedation. The aim of this study was to characterize how the addition of opioids sufficient to change the clinical level of sedation influenced the BIS and AAI.

Methods: Twenty-four adult volunteers received a target-controlled infusion of remifentanil (0-15 ng/ml) and inhaled sevoflurane (0-6 vol%) at various target concentration pairs. After reaching pseudo-steady state drug levels, the modified Observer's Assessment of Alertness/Sedation score, BIS, and AAI were measured at each target concentration pair. Response surface pharmacodynamic interaction models were built using the pooled data for each pharmacodynamic endpoint.

Results: Response surface models adequately characterized all pharmacodynamic endpoints. Despite the fact that sevoflurane-remifentanil interactions were strongly synergistic for clinical sedation, BIS and AAI were minimally affected by the addition of remifentanil to sevoflurane anesthetics.     

Volvulus of an Appendiceal Mucocele: Report of a Case

Few cases of volvulus of an appendiceal mucocele have been reported. The mechanism of torsion seems to be similar to that suggested for ovarian or appendegeal torsion, where a solid organ or mass fixed onto a narrow stalk is a precondition. We report the case of a young woman who presented with signs and symptoms of acute appendicitis. Computed tomography showed a cystic mass of fluid consistency in the right lower quadrant. An emergency laparoscopy revealed a 720° torsion of a gangrenous mucocele around the proximal part of the appendix. We performed a laparoscopic appendectomy and she recovered uneventfully. The presentation of volvulus of an appendiceal mucocele can mimic other common conditions. Prompt surgical intervention is essential to prevent gangrene and perforation. The combination of a cystic, right lower quadrant mass, and clinical findings suggestive of acute appendicitis should alert the clinician to include volvulus of an appendiceal mucocele in the differential diagnosis.     

Off-pump multivessel coronary artery surgery in high-risk patients

BACKGROUND: Coronary artery bypass surgery on cardiopulmonary bypass is associated with significant morbidity and mortality, which may be more marked in high-risk patients. We evaluated our results of off-pump coronary artery bypass (OPCAB) in high-risk patients with multivessel coronary artery disease and compared them with results in similar patients who underwent operation on cardiopulmonary bypass. METHODS: A total of 1,075 patients who underwent OPCAB between October 1996 and June 2001 and who had one or more of the following risk factors were included in the study: poor left ventricular function (EF < or = 30%), advanced age (> 70 years), left main stenosis, acute myocardial infarction, and redo coronary artery surgery. These patients were compared with 2,312 similar patients who underwent coronary artery bypass grafting on cardiopulmonary bypass during the same period. Preoperative risk factors, intraoperative variables, and postoperative results were analyzed and compared between two groups. RESULTS: The average number of grafts was 3.0 +/- 0.4 and 3.2 +/- 0.3 in the off-pump (OPCAB) and on-pump (CCAB) groups, respectively. Hospital mortality was 3.2% and 4.5% in OPCAB and CCAB groups respectively (p = 0.109). Perioperative myocardial infarction, requirement of inotropic agents, stroke, and renal dysfunction were comparable in two groups. Intubation time (19 +/- 5 vs 24 +/- 6 hours, p < 0.001), mean blood loss (362 +/- 53 vs 580 +/- 66 mL, p < 0.001), atrial fibrillation (14.3 vs 19.7%, p < 0.001), and prolonged ventilation (4.6 vs 7.6%, p = 0.002) were less in OPCAB group. Intensive care unit stay (20 +/- 8 hours) and hospital stay (6 +/- 3 days) were significantly less in the OPCAB group (p < 0.001). CONCLUSIONS: Off-pump coronary artery surgery can be safely performed in high-risk patients with multivessel coronary artery disease. Operative mortality is comparable to that associated with on-pump surgery, and avoidance of cardiopulmonary bypass is associated with reduced postoperative morbidity in these patients.     

Restarting LDLT During COVID-19: Early Results After Restructuring

IntroductionLiving-donor liver transplantation (LDLT) has been mostly suspended and deceased-donor living transplantation activity has been considerably reduced because of coronavirus disease 2019 (COVID-19). We modified our protocols and procedures in line with COVID-19 guidelines. Since the restructuring, we have performed 20 LDLTs. Our study reports the outcomes of these cases and demonstrates the feasibility of LDLT during this pandemic.Materials and MethodsThe changes were influenced by experiences and communications from across the globe. A month-long self-imposed moratorium was spent in restructuring the program and implementing new protocols. Twenty LDLTs were performed between April 18 and September 15 using the new protocols. Our experience includes 2 simultaneous liver-kidney transplants, 1 ABO-incompatible LDLT, and 1 pediatric case (age 11 months).ResultsNineteen patients recovered and 1 patient died. We maintained our postoperative immunosuppression protocol without many changes. Major complications were observed in 30% of recipients but none of the donors. One recipient was infected with COVID-19 during the postoperative period. A donor-recipient couple contracted COVID-19 after discharge from the hospital. All patients recovered from COVID-19 and liver enzymes were unaffected.ConclusionThis study represents a microcosm of experience in LDLT during the COVID-19 era. Outcomes of LDLT are not affected by COVID-19 per se, provided that we make necessary changes.     

Spinal compression due to ossified yellow ligament: a short series of 5 patients and literature review

BACKGROUND: Ossification of ligamentum flavum in the thoracic region causing compressive myelopathy among middle-aged patients is a poorly described entity. CASE DESCRIPTION: Five patients of Indian origin with OYL are described. Their clinical presentations, surgical options, and long-term outcome are presented. Radiologic and clinical follow-up of one of the patient is described over a span of 10 years. CONCLUSIONS: Decompressive laminectomy and excision of the OYL is the commonly performed surgical procedure. A rapid neurologic improvement follows decompression. The persistent spasticity in certain patients is attributed to irreversible changes within the cord. The disease is thought to be progressive in nature. The prolonged follow-up of these patients suggests that the long-term prognosis is poor. Selective racial involvement and variable clinical presentations, with treatment options, are discussed.     

Does aggressive statin therapy offer improved cholesterol-independent benefits compared to conventional statin treatment?

There is currently intense research interest in the properties of HMG-CoA reductase inhibitors (statins) beyond their well-documented lipid-lowering action. Studies have consistently demonstrated that administration of statin therapy decreases levels of the inflammatory marker C-reactive protein (CRP), a marker associated with an increased risk of cardiovascular events. This effect appears to be independent of the extent of reduction in total or LDL-cholesterol. Statins also appear to improve endothelial dysfunction by increasing endothelium-dependent vasodilatation. There is also evidence that statins inhibit fibrin formation and thrombus development, an effect that which would be clinically beneficial following plaque fissure or rupture. Early preclinical and clinical evidence suggests that there are quantitative differences between statin regimens in terms of their cholesterol-independent properties. Trials comparing equipotent doses of different statins, based on lipid-lowering efficacy, have not reported any differences in cholesterol-independent properties. However, the current evidence base indicates that more aggressive statin regimens are associated with an enhanced anti-inflammatory effect. Intensive lipid-lowering using statin therapy generates a greater reduction in mortality than standard lipid management, and it is possible that enhanced cholesterol-independent effects may account for some of this excess benefit.     

An elaborative NMR based plasma metabolomics study revealed metabolic derangements in patients with mild cognitive impairment: a study on north Indian population

Metabolic Brain Disease - Mild cognitive impairment (MCI) is transition phase between cognitive decline and dementia. The current study aims to investigate altered metabolic pattern in plasma of...