2022 American Society of Anesthesiologists Practice Guidelines for Management of the Difficult Airway.

The American Society of Anesthesiologists; All India Difficult Airway Association; European Airway Management Society; European Society of Anaesthesiology and Intensive Care; Italian Society of Anesthesiology, Analgesia, Resuscitation and Intensive Care; Learning, Teaching and Investigation Difficult Airway Group; Society for Airway Management; Society for Ambulatory Anesthesia; Society for Head and Neck Anesthesia; Society for Pediatric Anesthesia; Society of Critical Care Anesthesiologists; and the Trauma Anesthesiology Society present an updated report of the Practice Guidelines for Management of the Difficult Airway.

Correlation of supine MRI and standing radiographs for cervical sagittal balance in myelopathy patients: a cross-sectional study.

PURPOSE: Cervical sagittal alignment is correlated with myelopathy severity and used by spinal surgeons for surgical planification. Magnetic resonance imaging (MRI) is the gold standard for the evaluation of cervical myelopathy but may not be for the assessment of cervical sagittal balance compared to X-rays. The objective of this study was to assess the correlation of cervical alignment between supine MRI and standing radiographs in patients with cervical spondylotic myelopathy (CSM). METHODS: Cobb, Jackson and Harrison methods were used to measure cervical sagittal alignment on supine MRI and standing radiographs of CSM adults. Cervical alignment was divided based on Cobb angle values on lordotic (> 4°), kyphotic (< - 4°) and rectitude (- 4° to 4°). Correlations between radiographic and MRI measurements were determined. Intra- and interobserver reliability were assessed and MRI and X-Ray-measured angles were compared. RESULTS: One hundred and thirty patients with CSM were reviewed. Correlations of cervical lordosis measures between radiographs and MRI were strong using the Cobb (0.65) and Jackson (0.63) methods, and moderate using the Harrison (0.37) method. Mean cervical lordosis angle was significantly lower on supine MRI compared to standing radiographs for all methods (Cobb 11.6 Rx vs. 9.2 MRI, Jackson 14.6 vs. 11.6, Harrison 23.5 vs. 19.9). Eighteen patients (15.4%) without lordosis on supine MRI presented lordosis on standing radiographs. CONCLUSION: A substantial proportion of patients has sagittal alignment discrepancies between supine MRI and standing radiographs. Therefore, standing radiographs of the cervical spine should always be included in surgical planning of CSM patients.

A Randomized Controlled Trial Comparing Learners' Decision-making, Anxiety, and Task Load During a Simulated Airway Crisis Using Two Difficult Airway Aids.

INTRODUCTION: The American Society of Anesthesiologists (ASA) difficult airway algorithm and the Vortex approach are difficult airway aids. Our objective was to demonstrate that a simpler cognitive model would facilitate improved decision-making during a process such as difficult airway management. We hypothesized the simpler Vortex approach would be associated with less anxiety and task load. METHODS: Medical students were randomized to the ASA algorithm (n = 33) or Vortex approach (n = 34). All learned basic airway techniques on day 1 of their rotation. Next, they watched a video of their respective aid then managed a simulated airway crisis. We assessed decision-making using a seven-point airway management score and a completeness score. Completeness was at least one attempt at each of four techniques (mask ventilation, supraglottic airway, intubation, and cricothyrotomy). Two validated tools, the State-Trait Anxiety Inventory Form Y and the National Aeronautics and Space Administration Task Load Index, were used to assess anxiety and task load. RESULTS: Students in the Vortex group had higher airway management scores [4.0 (interquartile range = 4.0 to 5.0) vs. 4.0 (3.0 to 4.0), P = 0.0003] and completeness (94.1% vs. 63.6%, P = 0.003). In the ASA group, the means (SD) of National Aeronautics and Space Administration Task Load Index scores of 55 or higher were observed in mental [61.4 (14.4)], temporal [62.3 (22.9)], and effort [57.1 (15.6)] domains. In the Vortex group, only the temporal load domain was 55 or higher [mean (SD) = 57.8 (25.4)]. There was no difference in anxiety. CONCLUSIONS: Medical students perform better in a simulated airway crisis after training in the simpler Vortex approach to guide decision-making. Students in the ASA group had task load scores indicative of high cognitive load.

Preoperative magnetic resonance imaging is associated with baseline neurological status and can predict postoperative recovery in patients with cervical spondylotic myelopathy.

STUDY DESIGN: A blinded observational study of consecutive patients, prospectively enrolled and followed up to 1 year postoperatively. OBJECTIVE: To assess whether quantitative assessment of preoperative magnetic resonance imaging (MRI) predicts baseline patient status and postoperative neurological recovery. SUMMARY OF BACKGROUND DATA: Factors that can predict neurological recovery in patients with cervical spondylotic myelopathy (CSM) postoperatively are of great interest. Currently, the literature regarding the significance of MRI signal changes in relation to prognosis is inconsistent and conflicting. METHODS: A total of 57 consecutive patients with CSM were studied preoperatively and 1 year postoperatively. Modified Japanese Orthopaedic Association (mJOA), Nurick Grade, SF-36, neck disability index, 30-meter walk cadence (Wc) and time (Wt), grip strength, and Berg Balance Scale were administered at baseline and 1 year after surgery. Preoperative status and postoperative recovery were assessed in relation to quantitative MRI measurements pre- and postoperatively using univariate and multivariate analysis. RESULTS: Low T1 signal change preoperatively was associated with a lower mJOA (P = 0.0030), higher Nurick Grade (P = 0.0298), decreased grip (P = 0.0152), impaired Wt, Wc (P≤ 0.0001) and poor Berg Balance Scale (P = 0.0005) at baseline. Focal high T2 signal was associated with lower mJOA scores and higher Nurick Grade compared with diffuse T2 (P = 0.0035 P = 0.0079) or no T2 signal (P = 0.0680 P = 0.0122). Preoperative segmentation of T2 signal, showed a significant increase in Wt, Wc, and Berg Balance Scale (P = 0.0266; P = 0.0167; P = 0.0042). Preoperative T1 signal was associated with lower postoperative grip (P = 0.0260), greater Wt, Wc (P = 0.0360, P = 0.0090). Preoperative focal T2 signal had a significant association with poorer postoperative Wt, Wc (P = 0.0220) and Nurick Grade (P = 0.0230). Preoperative maximal cord compromise was negatively correlated with postoperative SF-36 mental score (P = 0.0130). CONCLUSION: MRI signal changes are predictive of baseline neurological status and postoperative recovery. MRI indicators of poorer outcome include the presence of low T1 signal, focal increased T2 signal and segmentation of T2 signal changes. LEVEL OF EVIDENCE: 2.

Transcriptomic analysis of human retinal detachment reveals both inflammatory response and photoreceptor death.

BACKGROUND: Retinal detachment often leads to a severe and permanent loss of vision and its therapeutic management remains to this day exclusively surgical. We have used surgical specimens to perform a differential analysis of the transcriptome of human retinal tissues following detachment in order to identify new potential pharmacological targets that could be used in combination with surgery to further improve final outcome. METHODOLOGY/PRINCIPAL FINDINGS: Statistical analysis reveals major involvement of the immune response in the disease. Interestingly, using a novel approach relying on coordinated expression, the interindividual variation was monitored to unravel a second crucial aspect of the pathological process: the death of photoreceptor cells. Within the genes identified, the expression of the major histocompatibility complex I gene HLA-C enables diagnosis of the disease, while PKD2L1 and SLCO4A1 -which are both down-regulated- act synergistically to provide an estimate of the duration of the retinal detachment process. Our analysis thus reveals the two complementary cellular and molecular aspects linked to retinal detachment: an immune response and the degeneration of photoreceptor cells. We also reveal that the human specimens have a higher clinical value as compared to artificial models that point to IL6 and oxidative stress, not implicated in the surgical specimens studied here. CONCLUSIONS/SIGNIFICANCE: This systematic analysis confirmed the occurrence of both neurodegeneration and inflammation during retinal detachment, and further identifies precisely the modification of expression of the different genes implicated in these two phenomena. Our data henceforth give a new insight into the disease process and provide a rationale for therapeutic strategies aimed at limiting inflammation and photoreceptor damage associated with retinal detachment and, in turn, improving visual prognosis after retinal surgery.

Postoperative magnetic resonance imaging can predict neurological recovery after surgery for cervical spondylotic myelopathy: a prospective study with blinded assessments.

BACKGROUND: Factors that can predict the recovery of cervical spondylotic myelopathy (CSM) patients postoperatively are of significant interest to physicians and patients and their families. Magnetic resonance imaging (MRI) scans are a common method of examination after surgery, and thus of interest as a predictor of outcome. OBJECTIVE: To investigate whether findings on MRI at 6 months postoperatively could predict recovery at 1 year in CSM patients. METHODS: In 52 consecutive prospective patients, MRI was performed preoperatively and 6 months postoperatively. T1 and T2 signal change (area, height, and segmentation) and spinal cord re-expansion were measured. Outcome measures evaluated at 1 year postoperatively were compared with preoperative values. Univariate and stepwise multiple regressions were undertaken. RESULTS: Using univariate analysis, patients whose cord failed to re-expand had poorer outcome according to the modified Japanese Orthopedic Association score and Nurick score (P = .014) and grip test (P = .006) postoperatively. Stepwise multivariate regression showed lack of cord re-expansion to be predictive of prognosis postoperatively in the modified Japanese Orthopedic Association score (P = .013) and Berg Balance Scale (P = .014), and walking test (P = .011). Postoperative hyperintense T2 signal change was predictive of worse outcome on the Berg Balance Scale (P = .014) and walking test (P = .020), Nurick score (P = .001), and Short Form-36 scores (P = .020). In cases in which the T2 signal intensified, there was a poorer outcome on Nurick scores (P = .013), grip test (P = .017), and Short Form-36 scores (P = .030). CONCLUSION: Findings on postoperative MRI at 6 months is of predictive value in determining outcomes in CSM patients. The persistence and type of T2 signal change and lack of re-expansion of the cord correlate with poorer recovery and likely reflect irreversible structural changes in the spinal cord.

The delta envelope: a technique for dose distribution comparison.

The gamma index is a tool that compares a dose distribution with a reference distribution by combining dose-difference and distance-to-agreement criteria. It has been widely used for ten years despite its high computational cost. This cost is due to both a search process for each reference point and the necessity to remove overestimations caused by the discrete nature of dose grids. The method proposed in this paper is much faster since it avoids both these problems. It consists in computing the delta envelope formed by the gamma ellipsoids around the points of the reference distribution. This delta envelope provides dose-difference tolerances that are then used to create new indices, called the delta indices, that provide useful information to interpret the deviations. Applied to both 1D and 2D test cases and compared to the gamma index, the S indices proved to be very accurate and intuitive. Their computational efficiency was evaluated on a 3D case: the delta envelope can be computed in 8 s on a 250 x 250 x 50 grid. Moreover it can be precomputed if the reference dose is known in advance. Then the delta indices are obtained in less than 2 s.