Perioperative Glycemic Surveillance and Control-Current Practices, Efficacy and Impact on Postoperative Outcomes following Infrainguinal Vascular Intervention.

BACKGROUND: Perioperative glycemic control plays a pivotal role in improving postsurgical outcomes. Hyperglycemia occurs frequently in surgical patients and has been associated with higher rates of mortality and postoperative complications. However, no current guidelines exist regarding intraoperative glycemic monitoring of patients undergoing peripheral vascular procedures and postoperative surveillance is often restricted to diabetic patients. We sought to characterize the current practices around glycemic monitoring and efficacy of perioperative glycemic control at our institution. We also examined the impact of hyperglycemia in our surgical population. METHODS: This was a retrospective cohort study performed at the McGill University Health Centre and Jewish General Hospital in Montreal, Canada. Patients undergoing elective open lower extremity revascularization or major amputation between 2019 and 2022 were included. Data collected from the electronic medical record included standard demographics, clinical, and surgical characteristics. Glycemic measurements and perioperative insulin use were recorded. Outcomes included 30-day mortality and postoperative complications. RESULTS: A total of 303 patients were included in the study. Overall, 38.9% of patients experienced perioperative hyperglycemia defined as glucose ≥180 mg/dL (10 mmol/L) during their hospital admission. Only 12 (3.9%) patients within the cohort underwent any intraoperative glycemic surveillance, while 141 patients (46.5%) had an insulin sliding scale prescribed postoperatively. Despite these efforts, 51 (16.8%) patients remained hyperglycemic for at least 40% of their measurements during their hospitalization. Hyperglycemia in our cohort was significantly associated with an increased risk of 30-day acute kidney injury (11.9% vs. 5.4%, P = 0.042), major adverse cardiac events (16.1% vs. 8.6%, P = 0.048), major adverse limb events (13.6% vs. 6.5%, P = 0.038), any infection (30.5% vs. 20.5%, P = 0.049), intensive care unit admission (11% vs. 3.2%, P = 0.006) and reintervention (22.9% vs. 12.4%, P = 0.017) on univariate analysis. Furthermore, multivariable logistic regression including the covariates of age, sex, hypertension, smoking status, diabetic status, presence of chronic kidney disease, dialysis, Rutherford stage, coronary artery disease and perioperative hyperglycemia demonstrated a significant relationship between perioperative hyperglycemia and 30-day mortality (odds ratio [OR]: 25.00, 95% confidence interval [CI]: 2.469-250.00, P = 0.006), major adverse cardiac events (OR: 2.08, 95% CI: 1.008-4.292, P = 0.048), major adverse limb events (OR: 2.24, 95% CI: 1.020-4.950, P = 0.045), acute kidney injury (OR: 7.58, 95% CI: 3.021-19.231, P < 0.001), reintervention (OR: 2.06, 95% CI: 1.117-3.802, P = 0.021), and intensive care unit admission (OR: 3.38, 95% CI: 1.225-9.345, P = 0.019). CONCLUSIONS: Perioperative hyperglycemia was associated with 30-day mortality and complications in our study. Despite this, intraoperative glycemic surveillance occurred rarely in our cohort and current postoperative glycemic control protocols and management failed to achieve optimal control in a significant percentage of patients. Standardized glycemic monitoring and stricter control in the intraoperative and postoperative period therefore represent an area of opportunity for reducing patient mortality and complications following lower extremity vascular surgery.

Declining institutional memory of open abdominal aortic aneurysm repair.

OBJECTIVE: Since its introduction, endovascular aneurysm repair (EVAR) has become a mainstay in the treatment of abdominal aortic aneurysms (AAAs), resulting in the decline of open aneurysm repairs. The objective of this study was to determine whether reduced open aneurysm repair frequency has led to a reduction in perioperative efficiency and increase in postsurgical complications. METHODS: A retrospective cohort study compared perioperative data and complications of 49 consecutive juxtarenal AAA (<1-cm neck) open repairs performed between 2014 and 2017 and 53 consecutive juxtarenal AAA controls (2005-2007) at The Ottawa Hospital. There was no change in surgical personnel during this 10-year comparison. RESULTS: The Ottawa Hospital experienced a 61% decline in the number of open AAA repairs between the two time periods examined; 541 open AAA repairs and 86 EVARs were performed between 2005 and 2007, whereas 358 open AAA repairs and 385 EVARs were performed between 2014 and 2017. Age of participants significantly decreased in the 2014 to 2017 group (P = .01), as did the number of women undergoing open juxtarenal AAA repair (P = .05). Total operating room time and anesthesia time were longer in the 2014-2017 group (P = .02; P = .01), whereas surgical times remained consistent (P = .13). Suprarenal clamp time and blood loss during the procedure were decreased in the 2014-2017 group (P < .01; P < .01). Intensive care unit stay and overall hospital stay were not significantly different between groups (P = .77; P = .87); however, there were large standard deviations observed for the 2014-2017 group. As well, 18.4% of patients in the 2014-2017 group experienced postsurgical complications of Clavien-Dindo grade IIIa or higher compared with 11.3% of patients in the historical control group (P = .07). Mortality also trended toward an increase in the 2014-2017 group (P = .43). CONCLUSIONS: The reduced rate of open repair performance at The Ottawa Hospital reflects the global trend toward EVAR. Anesthesia and operating room times increased during the period examined, reflecting a possible loss of expertise in the last decade. Complications also increased during this time for anatomically similar patients. Taken together, these findings may reflect a decreased institutional familiarity with open aneurysm repair and postsurgical care.

Combined Exercise and Nutrition Optimization for Peripheral Arterial Disease: A Systematic Review.

BACKGROUND: Patients with peripheral arterial disease (PAD) who suffer from claudication have a low exercise capacity, poor quality of life, and often severe disability. Exercise and healthy nutrition have been shown to be important factors to prevent disease progression. This systematic review aims to assess the evidence supporting the use of combined nutrition and structured exercise in patients with intermittent claudication. METHODS: Publications that included a combination of structured exercise (SE) and a nutritional intervention and that reported quality of life, exercise capacity, pain-free walking distance, limb blood flow hemodynamics, need for revascularization surgery, or surgical outcomes were systematically searched. Publications were screened, selected, and reviewed by 2 independent reviewers. RESULTS: Four publications were found reporting the effects of combined SE and nutrition programs. Pooled statistical analysis across trials was not performed because of the heterogeneity of study designs and type of interventions. Only 2 randomized controlled trials were found, reporting conflicting results with regard to the effects of combined SE and nutrition on exercise capacity. Only one trial reported quality of life measures. Blood flow was increased in the intervention involving inorganic nitrate in addition to SE. CONCLUSIONS: There are conflicting results and lack of quality data proving the benefit of nutrition and SE programs on patient-centered outcomes and limb blood flow. There are no data on the effects of combined nutrition and exercise on the need for revascularization surgery or postrevascularization outcomes. More randomized controlled trials are needed to assess the effects of multimodal interventions on patient-centered outcomes and clinical outcomes of PAD.

Atypical Primary Cutaneous Rosai Dorfman Disease: A Case Report.

BACKGROUND: Rosai Dorfman disease (RDD) is a rare disorder that typically presents with bilateral cervical lymphadenopathy and follows a benign course. OBJECTIVE: We present a case of late-onset atypical primary cutaneous RDD that is resistant to treatment modalities described in the literature. METHODS: Case report. RESULTS: An 84-year-old woman presented with a 7-year history of cutaneous lesions histologically consistent with RDD. She later failed initial treatments of acitretin and thalidomide. CONCLUSION: Physicians must be aware of unusual presentations of RDD. Also, further treatment options must be explored for patients resistant to classical management of RDD.

Electrophysiological white matter dysfunction and association with neurobehavioral deficits following low-level primary blast trauma.

There is strong evidence that primary blast injuries can cause neuropathological alterations in the brain. Clinical findings from war veterans indicating evidence of diffuse axonal injury have been corroborated by numerous primary blast models in animals. However, the effect of a subclinical blast (blast with no obvious sign of external trauma or lung injury) as a contributing factor to the neurological symptoms and neuropathology is less clear. Our group recently developed a model of low-level primary blast and characterized aberrant expression of white matter cytoskeletal proteins in the cortex and hippocampus following a subclinical wave shock exposure. Here we examined the susceptibility of the corpus callosum following subclinical blast. We also demonstrate that white matter dysfunction is associated with neurobehavioral deficits associated with anxiety and stress in rats. Anesthetized male Sprague-Dawley rats (~300 g) were exposed to a primary blast (approx. 28 kPa), below the threshold required to induce pulmonary trauma. Rats were evaluated on three behavioral outcome measures; the rotarod, the light/dark box and open field anxiety test. We used Western blotting to examine expression and degradation of axonally expressed αII-spectrin, NF200 and voltage-gated sodium channels (VGSC) in the corpus callosum. Acute slice preparations were used for electrophysiological analysis of evoked compound action potentials (CAPs) in the corpus callosum. There was evidence of αII-spectrin degradation in the corpus callosum at 48 h post-injury detectable up to 14 days post-injury, as well as increased heavy neurofilament expression. A reduction in VGSC expression was observed at 48 h post-blast as well as a reduction in the interaction between ankyrin G and intact αII-spectrin. Blast exposed rats had significantly lower rotarod latency times relative to sham rats (p=0.002). Increased anxiety-related and stress-related behavior were observed in blast rats relative to sham animals as indicated by the increased frequency of fecal droppings (p=0.029) and reduced exploratory activity (p=0.036) in the open-field test. Blast rats had fewer transitions and time spent in lit sections of the light/dark box. Electrophysiological recordings from the corpus callosum indicated greater deficits in unmyelinated fibers of the corpus callosum relative to myelinated fibers characterized by reduced CAP amplitude response at 14 days post-injury. Analysis of the relationship between stimulation distance to evoked response indicated an underlying abnormality in N1 myelinated fibers at close stimulation distances. Collectively, our results indicate that subclinical blast exposure can result in persistent neurological changes in cerebral white matter occurring in parallel with detectable neurobehavioral deficits.

Remote ischemic conditioning improves outcome independent of anesthetic effects following shockwave-induced traumatic brain injury.

Traumatic brain injury due to primary blast exposure is a major cause of ongoing neurological and psychological impairment in soldiers and civilians. Animal and human evidence suggests that low-level blast exposure is capable of inducing white matter injury and behavioural deficits. There are currently no effective therapies to treat the underlying suspected pathophysiology of low-level primary blast or concussion. Remote ischemic conditioning (RIC) has been shown to have cardiac, renal and neuro-protective effects in response to brief cycles of ischemia. Here we examined the effects of RIC in two models of blast injury. We used a model of low-level primary blast in rats to evaluate the effects of RIC neurofilament expression. We subsequently used a model of traumatic brain injury in adult zebrafish using pulsed high intensity focused ultrasound (pHIFU) to evaluate the effects of RIC on behavioural outcome and apoptosis in a post-traumatic setting. In blast exposed rats, RIC pretreatment modulated NF200 expression suggesting an innate biological buffering effect. In zebrafish, behavioural deficits and apoptosis due to pHIFU-induced brain injury were reduced following administration of serum derived from RIC rats. The results in the zebrafish model demonstrate the humoral effects of RIC independent of anesthetic effects that were observed in the rat model of injury. Our results indicate that RIC is effective in improving outcome following modeled brain trauma in pre- and post-injury paradigms. The results suggest a potential role for innate biological systems in the protection against pathophysiological processes associated with impairment following shockwave induced trauma.

Break out of the Classroom: The Use of Escape Rooms as an Alternative Teaching Strategy in Surgical Education.

OBJECTIVE: To implement and assess the impact of a Vascular Surgery-themed Escape Room on medical student motivation, satisfaction, and engagement in CanMEDS roles. DESIGN: The authors designed an Escape Room combining Vascular Surgery objectives, knowledge-based problems and technical skills into Vascular Surgery-themed stations. Groups of 3 to 4 medical students participated in the activity. Data collected included time to escape, CanMEDS roles covered during the activity, debriefing interview session, and satisfaction survey. SETTING: The Escape Room was installed at the University of Ottawa Skills and Simulation Centre at the Ottawa Hospital, a tertiary care center. PARTICIPANTS: Medical students in their preclerkship years of study were invited to participate in the Escape Room. In total, 13 medical students completed the experience, divided into 4 groups. RESULTS: Thirteen medical students divided into 4 groups participated in the Escape Room. Two teams used a collaborative strategy to complete the activity and successfully escaped with an average time of 53.6 minutes, whereas only 1 of the 2 teams completing the experience employing an individualistic strategy successfully escaped. Following the experience, 83% of participants stated that the experience motivated them to prepare beforehand and believed that the experience consolidated the knowledge that they had read. All the participants also reported that the experience encouraged the use of the CanMEDS communicator and collaborator roles. As well, 76.9% of students mentioned that they enjoyed the practical exercises incorporated into the experience and 53.8% stated that they would like to see the Escape Room format included in the medical curriculum. CONCLUSIONS: By combining knowledge-based problems, key learning objectives, technical skills, and CanMEDS themes into the Escape Room, the authors have developed a learning platform that may be more enjoyable and provide an adjunct to traditional didactic lectures.

Functions of NOD-Like Receptors in Human Diseases.

Nucleotide-binding and oligomerization domain NOD-like receptors (NLRs) are highly conserved cytosolic pattern recognition receptors that perform critical functions in surveying the intracellular environment for the presence of infection, noxious substances, and metabolic perturbations. Sensing of these danger signals by NLRs leads to their oligomerization into large macromolecular scaffolds and the rapid deployment of effector signaling cascades to restore homeostasis. While some NLRs operate by recruiting and activating inflammatory caspases into inflammasomes, others trigger inflammation via alternative routes including the nuclear factor-κB, mitogen-activated protein kinase, and regulatory factor pathways. The critical role of NLRs in development and physiology is demonstrated by their clear implications in human diseases. Mutations in the genes encoding NLRP3 or NLRP12 lead to hereditary periodic fever syndromes, while mutations in CARD15 that encodes NOD2 are linked to Crohn's disease or Blau's syndrome. Genome-wide association studies (GWASs) have identified a number of risk alleles encompassing NLR genes in a host of diseases including allergic rhinitis, multiple sclerosis, inflammatory bowel disease, asthma, multi-bacillary leprosy, vitiligo, early-onset menopause, and bone density loss in elderly women. Animal models have allowed the characterization of underlying effector mechanisms in a number of cases. In this review, we highlight the functions of NLRs in health and disease and discuss how the characterization of their molecular mechanisms provides new insights into therapeutic strategies for the management of inflammatory pathologies.