Research priorities of the Saskatchewan Provincial Department of Anesthesiology: a cross-sectional survey

Canadian Journal of Anesthesia/Journal canadien d'anesthésie -     

The ventricular residence time distribution derived from 4D flow particle tracing: a novel marker of myocardial dysfunction

4D flow cardiac magnetic resonance (CMR) imaging allows visualisation of blood flow in the cardiac chambers and great vessels. Post processing of the flow data allows determination of the residence time distribution (RTD), a novel means of assessing ventricular function, potentially providing additional information beyond ejection fraction. We evaluated the RTD measurement of efficiency of left and right ventricular (LV and RV) blood flow. 16 volunteers and 16 patients with systolic dysfunction (LVEF?<?50%) underwent CMR studies including 4D flow. The RTDs were created computationally by seeding virtual ‘particles’ at the inlet plane in customised post-processing software, moving these particles with the measured blood velocity, recording and counting how many exited per unit of time. The efficiency of ventricular flow was determined from the RTDs based on the time constant (RTDc?=???1/B) of the exponential decay. The RTDc was compared to ejection fraction, T1 mapping and global longitudinal strain (GLS). There was a significant difference between groups in LV RTDc (healthy volunteers 1.2?±?0.13 vs systolic dysfunction 2.2?±?0.80, p?<?0.001, C-statistic?=?1.0) and RV RTDc (1.5?±?0.15 vs 2.0?±?0.57, p?=?0.013, C-statistic?=?0.799). The LV RTDc correlated significantly with LVEF (R?=???0.84, P?<?0.001) and the RV RTDc had significant correlation with RVEF (R?=???0.402, p?=?0.008). The correlation between LV RTDc and LVEF was similar to GLS and LVEF (0.926, p?<?0.001). The ventricular residence time correlates with ejection fraction and can distinguish normal from abnormal systolic function. Further assessment of this method of assessment of chamber function is warranted.     

Transfusion Related Acute Lung Injury (TRALI) after Plasma Exchange in Myasthenic Crisis

Background  Transfusion-Related Acute Lung Injury (TRALI) is an uncommon but potentially fatal reaction that is both temporally and mechanistically related to receiving allogenic blood components. Although many patients with neurological disease receive plasma exchange, TRALI in a patient receiving plasma exchange for a neurological disease has not been previously reported. Case  A 79-year-old woman with an 18-month history of myasthenia gravis, was treated with a 4-day course of plasma exchange for symptomatic control of ptosis, diplopia, generalized fatigue, and chewing difficulties. On her fourth day of receiving plasma exchange, she experienced sudden-onset chest heaviness, diaphoresis, and dyspnea with hypoxemia, unresolved by 5 l of oxygen via nasal cannulae. She was initially investigated for a myocardial infarction and pulmonary embolus, but these were ruled out. Chest radiograph demonstrated bilateral pulmonary edema and she was clinically diagnosed with TRALI. Discussion  Although clinically identical to adult respiratory distress syndrome (ARDS), the association of TRALI with transfusion and its relatively lower mortality rate made it clinically distinct. Treatment is supportive, but patients who tolerate the initial reaction are likely to make full recovery within 72 h. Since prognosis can be excellent, identification and emergent management is essential, particularly in patients with comorbid neurological disease.     

Effect of chronic sustained-release dipyridamole on myocardial blood flow and left ventricular function in patients with ischemic cardiomyopathy

Dipyridamole increases adenosine levels and augments coronary collateralization in patients with coronary ischemia. This pilot study tested whether a 6-month course of sustained-release dipyridamole/aspirin improves coronary flow reserve and left ventricular systolic function in patients with ischemic cardiomyopathy. Six outpatients with coronary artery disease and left ventricular ejection fraction (LVEF) <40% were treated with sustained-release dipyridamole 200 mg/aspirin 25 mg twice daily for 6 months. Myocardial function and perfusion, including coronary sinus flow at rest and during intravenous dipyridamole-induced hyperemia, were measured using velocity-encoded cine magnetic resonance stress perfusion studies at baseline, 3 months, and 6 months. There was no change in heart failure or angina class at 6 months. LVEF increased by 39%+/-64% (31.0%+/-13.3% at baseline vs 38.3%+/-10.7% at 6 months; P=.01), hyperemic coronary sinus flow increased more than 2-fold (219.6+/-121.3 mL/min vs 509.4+/-349.3 mL/min; P=.01), and stress-induced relative myocardial perfusion increased by 35%+/-13% (9.4%+/-3.4% vs 13.9%+/-8.5%; P=.004). Sustained-release dipyridamole improved hyperemic myocardial blood flow and left ventricular systolic function in patients with ischemic cardiomyopathy.     

Studies of gastric emptying time in patients with non-ulcer dyspepsia

PURPOSE: To assess the gastric emptying pattern of a standardized solid meal in patients with non-ulcer dyspepsia by using scintigraphic techniques. METHODS: Results for the half-emptying time for solids (T1/2) and percent clearance of solid meal at 60 min (C60) of patients (n=35) having non-ulcer dyspepsia according to Rome II criteria were compared with age- and sex-matched controls (n=28). Gastric emptying was studied by using egg omelette labelled with Tc tin colloid. Data acquisition was done using two protocols: dynamic acquisition was performed for the first 100 min and then static acquisition was carried out for up to 4 h. T1/2 and C60 were calculated from the computer-generated time-activity curve. RESULTS: The normal range of T1/2 was 29-88 min (mean+/-2 SD) among the control group. The mean T1/2 of the patient group was 160.1+/-96.1 min (P<0.01). Twelve of 22 male patients and 11 of 13 female patients had prolonged T1/2. The normal range of C60 was 92-28% (mean+/-2 SD) in the control group. The mean C60 of the patient group was 33.1+/-18.5% (P<0.01). Fifteen of 22 male patients and 11 of 13 female patients had shortened C60. CONCLUSION: Gastric emptying is significantly delayed in both men and women having non-ulcer dyspepsia as the T1/2 is prolonged and the C60 is shortened in a significant number of these patients. Radionuclide tests might offer an objective way of assessing this particular aspect of gastric physiology.     

Needlestick injuries among electromyographers

The objective of this study was to determine the self‐reported prevalence of needlestick injuries among practicing electromyographers. In January 2008, an anonymous electronic survey was sent to all active members of the American Association for Neuromuscular and Electrodiagnostic Medicine (AANEM) who provided e‐mail addresses to the Association. Eight hundred and eight members (56% neurologists, 43% physiatrists; 97% practicing physicians, 3% trainees) responded, with a response rate of 22% (808 of 3659). The mean number of years in practice, involving electromyography (EMG) at least 1 day per week, was 16 years. A majority of physicians (64%) reported at least one needlestick injury involving EMG, and 8% reported five or more injuries. Needlestick injuries involving patients with human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS), hepatitis B, and/or hepatitis C occurred in 1 of every 11 electromyographers. Nearly half of all respondents (44%) who experienced a needlestick injury stated that they did not report at least one injury event to official centers. Injuries were most likely to occur during a routine procedure (45%) or when a patient moved (26%). The most common preventable reason for injury was a perceived lack of time. Muscle Nerve 38: 1541–1545, 2008