COVID-19 and the duration of operating room procedures in Ontario: a population-based retrospective study.

BACKGROUND: Studies have estimated that a large backlog of procedures was generated by emergency measures implemented in Ontario, Canada, at the onset of the COVID-19 pandemic, when nonessential and scheduled procedures were postponed. Understanding the impact of the COVID-19 pandemic on the time needed to perform a procedure may help to determine the resources needed to tackle the substantial backlog caused by the deferral of cases. The purpose of this study was to examine the duration of operating room (OR) procedures before and after the onset of the COVID-19 pandemic to inform planning around changes in required resources. METHODS: A population-based, retrospective cohort study was conducted using Ontario Health Insurance Plan claims data and other administrative health care data from Apr. 1, 2019, to Sept. 30, 2020. Statistical analysis was conducted using multivariate regression, with procedure duration as the outcome variable. RESULTS: Results showed that the average duration of nonelective procedures increased by 34 minutes during the COVID-19 period and by 19 minutes after the resumption of scheduled procedures. Controlling for physician, patient and hospital characteristics, and the procedure code submitted, procedure duration increased by 12 minutes in the nonelective COVID-19 period and by 5 minutes when scheduled procedures resumed, compared with the pre-COVID-19 period. CONCLUSION: Procedures may take longer in the COVID-19 period. This will affect wait times, which had already increased because of the deferral of procedures at the beginning of the pandemic, and will have an impact on Ontario's ability to provide patients with timely care.

Randomised trial of intravenous thiamine and/or magnesium sulphate administration on erythrocyte transketolase activity, lactate concentrations and alcohol withdrawal scores.

Alcohol withdrawal syndrome (AWS) occurs in 2% of patients admitted to U.K. hospitals. Routine treatment includes thiamine and benzodiazepines. Laboratory studies indicate that thiamine requires magnesium for optimal activity, however this has not translated into clinical practice. Patients experiencing AWS were randomized to three groups: (group 1) thiamine, (group 2) thiamine plus MgSO4 or (group 3) MgSO4. Pre- and 2-h post-treatment blood samples were taken. AWS severity was recorded using the Glasgow Modified Alcohol Withdrawal Score (GMAWS). The primary outcome measure was 15% change in erythrocyte transketolase activity (ETKA) in group 3. Secondary outcome measures were change in plasma lactate concentrations and time to GMAWS = 0. 127 patients were recruited, 115 patients were included in the intention-to-treat analysis. Pre-treatment, the majority of patients had normal or high erythrocyte thiamine diphosphate (TDP) concentrations (≥ 275-675/> 675 ng/gHb respectively) (99%), low serum magnesium concentrations (< 0.75 mmol/L) (59%), and high plasma lactate concentrations (> 2 mmol/L) (67%). Basal ETKA did not change significantly in groups 1, 2 or 3. Magnesium deficient patients (< 0.75 mmol/L) demonstrated less correlation between pre-treatment basal ETKA and TDP concentrations than normomagnesemic patients (R2 = 0.053 and R2 = 0.236). Median plasma lactate concentrations normalized (≤ 2.0 mmol/L) across all three groups (p < 0.001 for all groups), but not among magnesium deficient patients in group 1 (n = 22). The median time to achieve GMAWS = 0 for groups 1, 2 and 3 was 10, 5.5 and 6 h respectively (p < 0.001). No significant difference was found between groups for the primary endpoint of change in ETKA. Co-administration of thiamine and magnesium resulted in more consistent normalization of plasma lactate concentrations and reduced duration to achieve initial resolution of AWS symptoms.ClinicalTrials.gov: NCT03466528.

Clinical and radiological characteristics of acute pulmonary embolus in relation to 28-day and 6-month mortality.

BACKGROUND: Patients with acute pulmonary embolism (PE) exhibit a wide spectrum of clinical and laboratory features when presenting to hospital and pathophysiologic mechanisms differentiating low-risk and high-risk PE are poorly understood. OBJECTIVES: To investigate the prognostic value of clinical, laboratory and radiological information that is available within routine tests undertaken for patients with acute PE. METHODS: Electronic patient records (EPR) of patients who underwent Computed Tomography Pulmonary Angiogram (CTPA) scan for the investigation of acute PE during 6-month period (01.01.2016-30.06.2016) were examined. Data was gathered from EPR for patients that met inclusion criteria and all CTPA scans were re-evaluated. Biochemical thresholds of low-grade and high-grade inflammation, serum CRP >10mg/L and >150mg/L and serum albumin concentrations <35g/L and <25 g/L, were combined in the Glasgow Prognostic Score (GPS) and peri-operative Glasgow Prognostic Score (poGPS) respectively. Neutrophil Lymphocyte ratio (NLR) was also calculated. Pulmonary Embolus Severity Index score was calculated. RESULTS: Of the total CTPA reports (n = 2129) examined, 245 patients were eligible for inclusion. Of these, 20 (8%) patients had died at 28-days and 43 (18%) at 6-months. Of the 197 non-cancer related presentations, 28-day and 6-month mortality were 3% and 8% respectively. Of the 48 cancer related presentations, 28-day and 6-month mortality were 29% and 58% respectively. On univariate analysis, age ≥65 years (p<0.01), PESI score ≥100(p = <0.001), NLR ≥3(p<0.001) and Coronary Artery Calcification (CAC) score ≥ 6 (p<0.001) were associated with higher 28-day and 6-month mortality. PESI score ≥100 (OR 5.2, 95% CI: 1.1, 24.2, P <0.05), poGPS ≥1 (OR 2.5, 95% CI: 1.2-5.0, P = 0.01) and NLR ≥3 (OR 3.7, 95% CI: 1.0-3.4, P <0.05) remained independently associated with 28-day mortality. On multivariate binary logistic regression analysis of factors associated with 6-month mortality, PESI score ≥100 (OR 6.2, 95% CI: 2.3-17.0, p<0.001) and coronary artery calcification score ≥6 (OR 2.3, 95% CI: 1.1-4.8, p = 0.030) remained independently associated with death at 6-months. When patients who had an underlying cancer diagnosis were excluded from the analysis only GPS≥1 remained independently associated with 6-month mortality (OR 5.0, 95% CI 1.2-22.0, p<0.05). CONCLUSION: PESI score >100, poGPS≥1, NLR ≥3 and CAC score ≥6 were associated with 28-day and 6-month mortality. PESI score ≥100, poGPS≥1 and NLR ≥3 remained independently associated with 28-day mortality. PESI score ≥100 and CAC score ≥6 remained independently associated with 6-month mortality. When patients with underlying cancer were excluded from the analysis, GPS≥1 remained independently associated with 6-month mortality. The role of the systemic inflammatory response (SIR) in determining treatment and prognosis requires further study. Routine reporting of CAC scores in CTPA scans for acute PE may have a role in aiding clinical decision-making regarding treatment and prognosis.

High-intensity exercise training improves perioperative risk stratification in the high-risk patient.

Exercise prehabilitation prior to major surgery can improve cardiorespiratory fitness (CRF) and clinical outcome. However, in patients deemed "high--risk" for surgery, the feasibility, optimum training modality and its intensity, duration, and frequency are yet to be defined. We assessed the cardiorespiratory fitness of a 70-year-old female patient requiring major thoraco-abdominal surgery for reconstruction of her esophagus. Cardiopulmonary exercise testing (CPET) on a cycle ergometer was used to determine CRF. A baseline CPET confirmed poor CRF and placed her in a high surgical risk group. This was followed by 16 weeks of unsupervised, home-based, moderate-intensity steady-state (MISS) training followed by 10 weeks of high-intensity interval training (HIIT) under the combined supervision of an exercise physiologist and clinician in hospital. Following MISS training, CPET metrics failed to improve: peak oxygen uptake decreased (14.7-13.7 ml O2 ·kg-1 ·min-1 ; -7%) together with peak power (73-70 W; -4%) and anaerobic threshold (AT) increased (7.8-8.3 ml O2 ·kg-1 ·min-1 ; +6%). However, HIIT resulted in impressive improvement in CRF. Peak oxygen uptake (13.7-18.6 ml O2 ·kg-1 ·min-1 ; +36%), AT (8.3-10.5 ml O2 ·kg-1 ·min-1 ; +27%), peak power (70-102 W; +46%), minute ventilation (35.8-57.7 L·min-1 ; +61%), and peak heart rate (100-133 b·min-1 ; +33%) all increased. Ventilatory equivalents for carbon dioxide at AT ( V˙E / V˙ CO2 -AT) improved (30-28; -7%). The improvement in CRF resulted in surgical reclassification from high to low risk. In conclusion, preoperative HIIT training can confer a marked improvement in CRF in an elderly surgical patient and is associated with a corresponding reduction in perioperative risk.

A prospective evaluation of thiamine and magnesium status in relation to clinicopathological characteristics and 1-year mortality in patients with alcohol withdrawal syndrome.

BACKGROUND: Alcohol withdrawal syndrome (AWS) is routinely treated with B-vitamins. However, the relationship between thiamine status and outcome is rarely examined. The aim of the present study was to examine the relationship between thiamine and magnesium status in patients with AWS. METHODS: Patients (n = 127) presenting to the Emergency Department with AWS were recruited to a prospective observational study. Blood samples were drawn to measure whole blood thiamine diphosphate (TDP) and serum magnesium concentrations. Routine biochemistry and haematology assays were also conducted. The Glasgow Modified Alcohol Withdrawal Score (GMAWS) measured severity of AWS. Seizure history and current medications were also recorded. RESULTS: The majority of patients (99%) had whole blood TDP concentration within/above the reference interval (275-675 ng/gHb) and had been prescribed thiamine (70%). In contrast, the majority of patients (60%) had low serum magnesium concentrations (< 0.75 mmol/L) and had not been prescribed magnesium (93%). The majority of patients (66%) had plasma lactate concentrations above 2.0 mmol/L. At 1 year, 13 patients with AWS had died giving a mortality rate of 11%. Male gender (p < 0.05), BMI < 20 kg/m2 (p < 0.01), GMAWS max ≥ 4 (p < 0.05), elevated plasma lactate (p < 0.01), low albumin (p < 0.05) and elevated serum CRP (p < 0.05) were associated with greater 1-year mortality. Also, low serum magnesium at time of recruitment to study and low serum magnesium at next admission were associated with higher 1-year mortality rates, (84% and 100% respectively; both p < 0.05). CONCLUSION: The prevalence of low circulating thiamine concentrations were rare and it was regularly prescribed in patients with AWS. In contrast, low serum magnesium concentrations were common and not prescribed. Low serum magnesium was associated more severe AWS and increased 1-year mortality.

Pleomorphic giant cell carcinoma of the urinary bladder: an extreme form of tumour de-differentiation.

AIMS: Vesical pleomorphic giant cell carcinoma (PGCC) is a variant of urothelial carcinoma (UC) characterized by highly pleomorphic tumour with giant cells. Fewer than 10 cases have been reported, and our aim was to determine the clinical and pathological features of a series of tumours from a specialized uropathology laboratory. METHODS AND RESULTS: Thirteen cases of PGCC of the bladder were identified. There were nine males and four females, ranging in age from 53 to 92 years (mean 72 years). Associated conventional high-grade UC was seen in eight cases, while three cases also had micropapillary UC and one plasmacytoid UC. UC in situ (CIS) was present in five cases and occasional bizarre cells were seen in both UC and CIS. The proportion of PGCC present varied from 40% to 100% of tumour. Immunostaining performed on 10 cases showed uniform positivity for CK 8/18 and AE1/AE3, while most tumours were positive for CK7, CK20, uroplakin III and GATA binding protein 3 (GATA3). ß-human chorionic gonadotrophin (ß-hCG) was negative. Of 10 patients with follow-up, five died within 1 year and four are alive with tumour. CONCLUSIONS: The association of PGCC with UC and an overlap in immunoexpression suggests that PGCC represents an extreme form of UC de-differentiation.

Value of uroplakin III in distinguishing variants of primary bladder urothelial carcinoma from malignancy metastatic to the urinary bladder.

BACKGROUND: Urothelial carcinoma (UC) variants can be difficult to differentiate from carcinoma metastatic to the bladder. MATERIALS AND METHODS: We examined immunostaining for uroplakin III in 43 cases of primary bladder UC variants including micropapillary UC (n=19), nested variant of UC (n=2), pleomorphic giant-cell carcinoma (n=8), plasmacytoid UC (n=4), lymphoepithelioma-like carcinoma (n=2), large cell undifferentiated carcinoma (n=2), UC with abundant myxoid stroma (n=3) and lipid cell variant (n=3) and in 11 tumors from other organs metastatic to the bladder. These tumors included invasive ductal carcinoma of the breast (n=2), colorectal adenocarcinoma (n=4), endometrioid adenocarcinoma (n=1) and serous papillary carcinoma of the uterus (n=1) melanoma (n=1), embryonal carcinoma of the testis (n=1), and renal clear cell carcinoma (n=1). RESULTS: Out of the 43 UC variants, 35 (81%) were positive for uroplakin III, including micropapillary, lipid cell variant and UC with abundant myxoid stroma. Pleomorphic giant cell carcinoma, plasmacytoid UC and nested variant of UC were less commonly positive. Of the 11 metastatic tumors, six were found to be positive for uropIakin III: metastatic colorectal adenocarcinoma, clear cell carcinoma of the kidney and embryonal carcinoma of testis. CONCLUSION: UP III Positivity for uroplakin III is not found only in primary bladder UC variants, but in some tumors that have metastatized to the bladder. Staining for uroplakin III alone should not be taken as evidence of UC.

Distal seminal vesicle invasion by prostate adenocarcinoma does not occur in isolation of proximal seminal vesicle invasion or lymphovascular infiltration.

AIMS: Seminal vesicle (SV) invasion by prostatic adenocarcinoma is a poor prognostic indicator. Despite this, there are currently no guidelines regarding SV sampling in radical prostatectomy specimens. This study examines the distribution of invasive prostatic adenocarcinoma in SVs and makes recommendations regarding sampling procedures. METHOD: The SVs from 773 consecutive radical prostatectomy specimens were serially sectioned and blocked entirely, with sections grouped into the proximal, mid and distal thirds of the glands. The site of invasive prostatic carcinoma within the muscular wall of the SV and its presence in the ejaculatory duct was recorded. RESULTS: SV invasion (pT3b) was present in 56 (7.2%) cases. Patients ranged in age from 52 to 73 years (mean 64 years), with a serum prostatic specific antigen ranging from 3.7 to 46 ng/mL (mean 10.6 ng/mL). Fourteen patients (25%) had a palpable nodule or induration on digital rectal examination. Ejaculatory duct involvement was present in 49 cases. Forty-seven of 49 (95.9%) cases with ejaculatory duct involvement also had SV invasion. The mean tumour volume was 5.53 cm(3) (range 1.0-12.1 cm(3)). The tumours had a Gleason score of 4 + 3 in five cases, 4 + 3 with tertiary pattern 5 in 12 cases, 8 in two cases and 5 + 4/4 + 5 in 37 cases. All but one of the SV positive cases (98.2%) had involvement of the proximal third (15 right, 17 left and 23 both) of the gland, 35 of which (63.6%) had infiltration only of the proximal SV. For the remainder, 11 also had mid third and nine had mid and distal third involvement. Lymphovascular invasion within the prostate was seen in 71.4% of cases. In one of these cases involvement of the distal right SV was present in the absence of involvement of the proximal or mid SV. CONCLUSIONS: In this study, as distal SV invasion in the absence of proximal SV invasion was found in <2% of cases, we conclude that sampling of the proximal third of the SVs is sufficient to identify virtually all cases of tumour infiltration into the SVs. If lymphovascular invasion is present in the absence of proximal SV invasion, then the remaining parts of the SV must be examined. Also, in cases with involvement of the ejaculatory duct, thorough examination of the SV is warranted.

Unilateral arm strength training improves contralateral peak force and rate of force development.

Neural adaptation following maximal strength training improves the ability to rapidly develop force. Unilateral strength training also leads to contralateral strength improvement, due to cross-over effects. However, adaptations in the rate of force development and peak force in the contralateral untrained arm after one-arm training have not been determined. Therefore, we aimed to detect contralateral effects of unilateral maximal strength training on rate of force development and peak force. Ten adult females enrolled in a 2-month strength training program focusing of maximal mobilization of force against near-maximal load in one arm, by attempting to move the given load as fast as possible. The other arm remained untrained. The training program did not induce any observable hypertrophy of any arms, as measured by anthropometry. Nevertheless, rate of force development improved in the trained arm during contractions against both submaximal and maximal loads by 40-60%. The untrained arm also improved rate of force development by the same magnitude. Peak force only improved during a maximal isometric contraction by 37% in the trained arm and 35% in the untrained arm. One repetition maximum improved by 79% in the trained arm and 9% in the untrained arm. Therefore, one-arm maximal strength training focusing on maximal mobilization of force increased rapid force development and one repetition maximal strength in the contralateral untrained arm. This suggests an increased central drive that also crosses over to the contralateral side.