The effect of COVID-19 on a Major Trauma Network. An analysis of mechanism of injury pattern, referral load and operative case-mix

PURPOSE

The aim of this study was to evaluate changes in both mechanism and diagnoses of injuries presenting to the orthopaedic department during this lockdown period, as well as to observe any changes in operative case-mix during this time.

METHODS

A study period of twelve weeks following the introduction of the nationwide "lockdown period", March 23^rd - June 14^th, 2020 was identified and compared to the same time period in 2019 as a "baseline period". A retrospective analysis of all emergency orthopaedic referrals and surgical procedures performed during these time frames was undertaken. All data was collected and screened using the 'eTrauma' management platform (Open Medical, UK). The study included data from a five NHS Foundation Trusts within North West London. A total of 6695 referrals were included for analysis.

RESULTS

The total number of referrals received during the lockdown period fell by 35.3% (n=2631) compared to the same period in 2019 (n=4064). Falls remained proportionally the most common mechanism of injury across all age groups in both time periods. The proportion sports related injuries compared to the overall number of injuries fell significantly during the lockdown period (p<0.001), however, the proportion of pushbike related accidents increased significantly (p<0.001). The total number of operations performed during the lockdown period fell by 38.8% (n=1046) during lockdown (n=1732). The proportion of patients undergoing operative intervention for Neck of Femur (NOF) and ankle fractures remained similar during both study periods. A more non-operative approach was seen in the management of wrist fractures, with 41.4% of injuries undergoing an operation during the lockdown period compared to 58.6% at baseline (p<0.001).

CONCLUSION

In conclusion, the nationwide lockdown has led to a decrease in emergency orthopaedic referrals and procedure numbers. There has been a change in mechanism of injuries, with fewer sporting injuries, conversely, there has been an increase in the number of pushbike or scooter related injuries during the lockdown period. NOF fractures remained at similar levels to the previous year. There was a change in strategy for managing distal radius fractures with more fractures being treated non-operatively.

Abstract P6-09-04: The Association of Low Level Arm Volume Increases with Lymphedema Symptoms Following Treatment for Breast Cancer

Purpose/Objective: The symptoms associated with breast cancer-related lymphedema are well-documented, and include sensations of heaviness, swelling, and tightness in the upper extremity and trunk. However, the clinical significance of low-level arm volume changes frequently experienced by breast cancer patients is not well understood. We sought to determine the association of low level arm volume changes with patient-reported lymphedema symptoms in women treated for breast cancer.

Methods: 267 patients who underwent surgical treatment for breast cancer from 2010–2012 were identified from a cohort of patients prospectively screened for lymphedema at our institution. Patients were assessed with perometer arm volume measurements and a survey of lymphedema symptoms pre and post operatively, and at 3–7 month intervals thereafter. Inclusion in this analysis was limited to unilaterally affected women with ≥ 3 assessments and ≥ 6 months of post-surgical follow-up. Arm volume changes were quantified as Relative Volume Change (RVC): RVC = (A2*U1)/(U2*A1) − 1, where A1 is pre-operative arm volume and A2 is post-operative arm volume on the affected side, and U1 and U2 are arm volumes on the unaffected side at these time points. Low level arm volume change was defined as a measurement with RVC ≥ 5% &lt;10% at an assessment ≥ 3 months post-operatively. Actuarial univariate and multivariate regression analysis was performed to determine the association of low level arm volume change with patient-reported lymphedema symptoms and clinicopathological characteristics.

Results: Low level arm volume changes occurred in 21.7% (58/267) of patients during the follow-up period at a median of 10.4 months post-operatively. Median post-operative follow-up was 12.4 months and 5 assessments per patient. By actuarial univariate analysis, symptoms of larger arm, shoulder, or neck (p &lt; 0.001), tighter sleeve, sleeve cuff, or ring (p &lt; 0.001), and having undergone axillary lymph node dissection (p = 0.02) or regional lymph node radiation (p = 0.01) were significantly associated with low-level arm volume change. By actuarial multivariate analysis, only symptoms of larger arm, shoulder, or neck (p &lt; 0.0001) were associated with low level arm volume change.

Conclusions: This data suggests that patients may be symptomatic for lymphedema even when experiencing low level arm volume changes. These patients should be followed closely for progression of measured arm volume or heightened lymphedema symptoms suggesting progression of the condition.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P6-09-04.

Blood concentrations of everolimus are markedly increased by ketoconazole

The authors sought to quantify the influence of the CYP3A and P-glycoprotein inhibitor ketoconazole on the pharmacokinetics of everolimus in healthy subjects. This was a 2-period, single-sequence, crossover study in 12 healthy subjects. In period 1, subjects received the reference treatment of a single 2-mg dose of everolimus. In period 2, they received the test treatment of ketoconazole 200 mg twice daily for a total of 8 days and a single dose of everolimus coadministered on the fourth day of ketoconazole therapy. The test/reference ratio and 90% confidence interval were derived for everolimus maximum concentration and area under the curve. During ketoconazole coadministration, everolimus maximum concentration increased 3.9-fold (90% confidence interval, 3.4-4.6) from 15 +/- 4 ng/mL to 59 +/- 13 ng/mL. Everolimus area under the curve increased 15.0-fold (90% confidence interval, 13.6-16.6) from 90 +/- 23 ng*h/mL to 1324 +/- 232 ng*h/mL. Everolimus half-life was prolonged by 1.9-fold from 30 +/- 4 hours to 56 +/- 5 hours. Everolimus did not appear to alter ketoconazole predose concentrations. Given the magnitude of this drug interaction, use of ketoconazole should be avoided if possible in everolimus-treated patients.

Attenuation of the kaluretic properties of furosemide by triamterene (Dyrenium®) in healthy volunteers

OBJECTIVE

To examine if concomitant administration of furosemide, a loop diuretic, with the potassium- and magnesium-sparing diuretic triamterene would decrease loss of potassium and magnesium while improving diuresis.

METHODS

In this open-label, three-way crossover study, healthy subjects were randomized to receive treatment with 40 mg furosemide, with 150 mg triamterene, or treatment with 40 mg furosemide and 150 mg triamterene. Urine samples were collected 24 hours before dosing and between 0 - 1, 1 - 2, 2 - 3, 3 - 4, 4 - 6, 6 - 8, 8 - 12, and 12 - 24 hours post-dosing. Sodium and potassium levels were measured by an ion-selective electrode method. Magnesium was measured colorimetrically using a xylidyl blue reaction.

RESULTS

Co-administration of furosemide with triamterene resulted in enhanced diuresis, particularly in the first 0 - 12 hours post-dose, compared with either furosemide or triamterene alone. Compared to individual treatments, combination therapy significantly increased urinary sodium excretion (p = 0.0001) while significantly decreasing urinary potassium excretion (p = 0.0001); importantly, the magnesium-sparing characteristic of triamterene was retained with furosemide co-administration.

CONCLUSION

Triamterene, when used in combination with the loop diuretic, furosemide, preserves intracellular potassium and magnesium while enhancing the natriuretic effect of furosemide.

Effect of multiple-dose erythromycin on everolimus pharmacokinetics

OBJECTIVE

We sought to quantify the influence of the CYP3A inhibitor erythromycin on the pharmacokinetics of everolimus, a CYP3A substrate.

METHODS

This was a two-period, single-sequence, crossover study in 16 healthy subjects. In period 1, subjects received the reference treatment of a single 2-mg dose of everolimus. In period 2, they received the test treatment of erythromycin 500 mg three times daily for a total of 9 days and a single 2-mg dose of everolimus coadministered on the fifth day of erythromycin therapy. The test/reference ratio and 90% confidence interval (CI) were derived for everolimus C (max) and AUC.

RESULTS

During erythromycin coadministration, everolimus C (max) increased 2.0-fold (90% CI, 1.8-2.3) from 20+/-5 ng/ml to 40+/-10 ng/ml. Everolimus AUC increased 4.4-fold (90% CI, 3.5-5.4) from 116+/-37 ng h/ml to 524+/-225 ng h/ml. Everolimus half-life was prolonged by 39% from 32+/-6 h to 44+/-6 h. Erythromycin predose concentrations were not changed after single-dose administration of everolimus.

CONCLUSION

Multiple-dose erythromycin increased single-dose everolimus blood levels by an average 4.4-fold (range, 2.0-12.6). During erythromycin treatment, a compensatory everolimus dose reduction should be made guided by everolimus therapeutic drug monitoring.

The dependency of calcium set point on basal plasma calcium in dialysis patients: a better explanation for the discrepancies regarding its link with PTH secretion than methodological differences

BACKGROUND

The increase of calcium (Ca) set point in uremic hyperparathyroid patients and its decrease with calcitriol therapy are controversial. Besides methodological differences regarding the experimental protocol for obtaining the sigmoidal curve, mainly differences in definitions of maximal PTH (peak or steady value) and of calcium set point itself have been proposed for the discrepant conclusions. However, two other explanations are possible: the various aluminum load of the patients and the dependency of Ca set point upon the basal plasma ionized calcium (PCa).

PATIENTS AND METHODS

Therefore the Ca set point was measured in 2 groups of patients on maintenance dialysis never exposed to aluminum, one of 7 patients with normosecretion of PTH (NPT) and the other of 8 patients with hyperparathyroidism (HPT) before and after 3 intravenous administration of 4 microg of alfacalcidol in a week. The sigmoidal curve was established during a zero Ca dialysis, without Ca replacement for the first 90 minutes and with intravenous infusion of 41 mmoles of Ca during the 150 last minutes. The curvilinear decrease of PCa induced a peak of PTH followed by a decrease while PCa was still decreasing up to the 90th minute. Therefore PTHmax was taken both at the peak and at its lower value observed at the 90th minute (steady PTHmax). Experimental determinations of the Ca set point were made using both definitions of Brown and Felsenfeld and both PTHmax values. In basal conditions, while using any of the values given by the same calculation methodology, Ca set point was not different in NPT and HPT patients. After alfacalcidol, no change in plasma PTH nor in Ca set point was observed in HPT patients. In contrast, in NPT patients alfacalcidol induced a significant decrease of plasma PTH concentrations in association with an increase in basal PCa and in Ca set point, whatever the definitions of the latter and of PTHmax. Calcitriol induced changes in Ca set point and basal PCa were correlated.

CONCLUSIONS

1) In normocalcemic dialysis patients never exposed to aluminium hyperparathyroidism is not explained by an increased Ca set point 2) Calcitriol suppressive effect on PTH secretion is neither explained by a decrease in Ca set point. 3) Ca set point as measured in vivo does not reflect an intrinsic characteristic of the parathyroid glands since it varies with basal PCa. Better than methodological differences, this dependency may explain the discrepant conclusions between the various clinical investigations.

A simplified method for typing haemoglobin using ultrathin-layer isoelectric focusing

Haemoglobin alleles were identified by isoelectric focusing using ultrathin-layer polyacrylamide gels, containing pH 3.0-10.0 ampholytes. The run parameters were chosen to co-ordinate with other isoelectric focusing methods currently used by the authors' laboratory. The method devised separated the A, F, S, and C alleles.

Differentiation of alpha-amylase from various sources: an approach using selective inhibitors

A radial diffusion assay in an agarose/starch gel utilizing crude kidney bean extract and a commercially prepared alpha-amylase inhibitor isolated from wheat seeds was developed and assessed to determine its ability to differentiate alpha-amylase from various sources. Kidney bean extract was found to have a greater inhibitory effect on AMY2, while the wheat lectin inhibitor was found to have a greater inhibitory effect on AMY1. Neither inhibitor was found to have any effect on commercially prepared bacterial alpha-amylase extract in both liquid preparations and dried stains. Mixtures of varying concentrations of pancreatic and salivary extracts also gave interpretable results. Additionally, dried stains prepared from human body fluids having high levels of AMY2 were differentiated from dried stains prepared from human body fluids containing high levels of AMY1.