Intraoperative Monitoring of Scoliosis Surgery in Young Patients.

SUMMARY: Intraoperative neurophysiologic monitoring has added substantially to the safety of spinal deformity surgery correction since its introduction over four decades ago. Monitoring routinely includes both somatosensory evoked potentials and motor evoked potentials. Either modality alone will detect almost all instances of spinal cord injury during deformity correction. The combined use of the two modalities provides complementary information, can permit more rapidly identification of problems, and enhances safety though parallel redundancy should one modality fail. Both techniques are well established and continue to be refined. Although there is room for provider preference, proper monitoring requires attention to technical detail, understanding of the underlying physiology, and familiarity with effects of commonly used anesthetic agents.

Perioperative Analgesia in Spine Surgery: A Review of Current Data Supporting Future Direction.

This Clinical Research discusses the diverse nature of spine surgery procedures and the use of multimodal analgesia within enhanced recovery after surgery (ERAS) protocols to improve patient outcomes. Spine surgeries range from minor decompressions to extensive tumor resections, performed by neurosurgeons or orthopedic spine surgeons on adults and children. To manage perioperative pain effectively, various methods have been employed, including multimodal analgesia within ERAS protocols. Incorporating ERAS protocols into spine surgery has shown benefits such as reduced pain scores, decreased opioid use, shorter hospital stays, and improved functionality. ERAS protocols help to enhance patient outcomes, focusing on deconstructing these protocols for surgeons and anesthesiologists.

THE EFFECTS OF PERIOPERATIVE DEXAMETHASONE ON GLYCEMIC CONTROL AND POSTOPERATIVE OUTCOMES.

Objective: Perioperative glucocorticoids are commonly given to reduce pain and nausea in patients undergoing surgery. However, the glycemic effects of steroids and the potential effects on morbidity and mortality have not been systematically evaluated. This study investigated the association between perioperative dexamethasone and postoperative blood glucose, hospital length of stay (LOS), readmission rates, and 90-day survival. Methods: Data from 4,800 consecutive orthopedic surgery patients who underwent surgery between 2000 and 2016 within a single health system were analyzed retrospectively. Results: Patients with and without diabetes mellitus (DM) who were given a single dose of dexamethasone had higher rates of hyperglycemia during the first 24 hours after surgery as compared to those who did not receive dexamethasone (hazard ratio [HR] was 1.81, and 95% confidence interval [CI] was [1.46, 2.24] for the DM cohort; HR 2.34, 95% CI [1.66, 3.29] for the nonDM cohort). LOS was nearly 1 day shorter in patients who received dexamethasone (geometric mean ratio [GMR] 0.79, 95% CI [0.75, 0.83] for patients with DM; GMR 0.75, 95% CI [0.72, 0.79] for patients without DM), and there was no difference in 90-day readmission rates. In patients without DM, dexamethasone was associated with a higher 90-day overall survival (99.07% versus 96.90%; P = .004). Conclusion: In patients with and without DM who undergo orthopedic surgery, perioperative dexamethasone was associated with a transiently higher risk of hyperglycemia. However, dexamethasone treatment was associated with a shorter LOS in patients with and without DM, and a higher overall 90-day survival rate in patients without DM, compared to patients who did not receive dexamethasone. Abbreviations: BMI = body mass index; CAD = coronary artery disease; CI = confidence interval; DM = diabetes mellitus; GMR = geometric mean ratio; HR = hazard ratio; IV = intravenous; LOS = length of stay; POD = postoperative day.

Imaging in Chronic Traumatic Encephalopathy and Traumatic Brain Injury.

CONTEXT: The diagnosis of chronic traumatic encephalopathy (CTE) can only be made pathologically, and there is no concordance of defined clinical criteria for premorbid diagnosis. The absence of established criteria and the insufficient imaging findings to detect this disease in a living athlete are of growing concern. EVIDENCE ACQUISITION: The article is a review of the current literature on CTE. Databases searched include Medline, PubMed, JAMA evidence, and evidence-based medicine guidelines Cochrane Library, Hospital for Special Surgery, and Cornell Library databases. STUDY DESIGN: Clinical review. LEVEL OF EVIDENCE: Level 4. RESULTS: Chronic traumatic encephalopathy cannot be diagnosed on imaging. Examples of imaging findings in common types of head trauma are discussed. CONCLUSION: Further study is necessary to correlate the clinical and imaging findings of repetitive head injuries with the pathologic diagnosis of CTE.

MRI analysis of the size and shape of the oropharynx in chronic whiplash.

OBJECTIVES: To quantify differences in the size/shape of the oropharynx between female subjects with whiplash and controls. DESIGN: Retrospective cohort. METHODS: A total of 113 subjects (79 whiplash, 34 controls) were included. T1-weighted MRI was used to measure 1) cross-sectional area (CSA [mm(2)]) and 2) shape ratios for the oropharynx. Reliability data were established. RESULTS: Whiplash subjects had significantly smaller oropharynx CSAs (P < 0.001) and shape ratios (P < 0.001) compared with healthy controls. Self-reported levels of pain and disability and duration of symptoms were not associated with size and shape of the oropharynx in whiplash subjects (P = 0.75 and P = 0.99, respectively). Age and BMI did influence the size (P = 0.01) and shape of the oropharynx (P < 0.001) in the whiplash subjects, but only 20 to 30 percent of the variance could be explained by these factors. CONCLUSION: Significant difference in the size and shape of the oropharynx was noted in subjects with chronic whiplash compared with controls. Future studies are required to investigate the relationships between oropharynx morphometry and symptoms in patients with chronic whiplash.

Red blood cell arginase suppresses Jurkat (T cell) proliferation by depleting arginine.

BACKGROUND: Transfusion of packed red blood cells (PRBC) suppresses immunity, but the mechanisms are incompletely understood. PRBCs contain arginase, an enzyme which converts arginine to ornithine and depletes arginine in vitro. Arginine depletion suppresses proliferation of Jurkat T cells in other models. We hypothesize that PRBC arginase-mediated arginine depletion will suppress proliferation of T cells. METHODS: A transfusion model was designed adding PRBC to culture RPMI media with or without an irreversible arginase blocker (nor-NOHA), incubating for 6-48 hours and then removing the PRBCs. Amino acid concentrations in the media were measured using liquid chromatography mass spectrometry. T cells were then added to the pre-conditioned media, cultured for 24 hours, and proliferation was measured. RESULTS: PRBC depleted arginine significantly and increased ornithine in media compared to baseline PRBC treated wells and significantly decreased T cell proliferation. These effects were enhanced with volume of PRBC exposure. Nor-NOHA inhibition of arginase restored T cell proliferation in PRBC treated cultures. CONCLUSIONS: Jurkat T cell proliferation was impaired by PRBC in clinically relevant volumes. The mechanism influencing T cell impairment appears to result from arginine depletion by arginase. Arginine depletion by PRBC arginase may be a novel mechanism for immunosuppression after transfusion.