[A functional approach to disorders of the loco-motor system-a way to a better understanding?]

BACKGROUND

Disorders of the loco-motor system are frequent and expensive. The current method of diagnosing and treating these disorders does not appear to be successful.

DIAGNOSTICS

A functional approach based on the model of the functional system incorporates all aspects relevant to disorders of the loco-motor system. Most disturbances the system can compensate. If compensating mechanisms are not sufficient, the system decompensates, and symptoms develop. It is important to search not only for structural changes but also for somatic dysfunction, psychosocial factors, and changes in neuromodulation. On this basis, treatment strategies can be developed. If there are complex disturbances on different levels, a multimodal interdisciplinary treatment is indicated. The model of the functional system highlights the important role of manual medicine in the diagnostics, treatment, prevention, and rehabilitation of disorders of the loco-motor system.

What level of D-dimers can safely exclude pulmonary embolism in COVID-19 patients presenting to the emergency department?

OBJECTIVES

To identify which level of D-dimer would allow the safe exclusion of pulmonary embolism (PE) in COVID-19 patients presenting to the emergency department (ED).

METHODS

This retrospective study was conducted on the COVID database of Assistance Publique - Hôpitaux de Paris (AP-HP). COVID-19 patients who presented at the ED of AP-HP hospitals between March 1 and May 15, 2020, and had CTPA following D-dimer dosage within 48h of presentation were included. The D-dimer sensitivity, specificity, and positive and negative predictive values were calculated for different D-dimer thresholds, as well as the false-negative and failure rates, and the number of CTPAs potentially avoided.

RESULTS

A total of 781 patients (mean age 62.0 years, 53.8% men) with positive RT-PCR for SARS-Cov-2 were included and 60 of them (7.7%) had CTPA-confirmed PE. Their median D-dimer level was significantly higher than that of patients without PE (4,013 vs 1,198 ng·mL^-1, p < 0.001). Using 500 ng·mL^-1, or an age-adjusted cut-off for patients > 50 years, the sensitivity and the NPV were above 90%. With these thresholds, 17.1% and 31.5% of CTPAs could have been avoided, respectively. Four of the 178 patients who had a D-dimer below the age-adjusted cutoff had PE, leading to an acceptable failure rate of 2.2%. Using higher D-dimer cut-offs could have avoided more CTPAs, but would have lowered the sensitivity and increased the failure rate.

CONCLUSION

The same D-Dimer thresholds as those validated in non-COVID outpatients should be used to safely rule out PE.

KEY POINTS

• The median D-dimer level was significantly higher in COVID-19 patients with PE as compared to those without PE (4,013 ng·mL^-1 vs 1,198 ng·mL^-1 respectively, p < 0.001). • Using 500 ng·mL^-1, or an age-adjusted D-dimer cut-off to exclude pulmonary embolism, the sensitivity and negative predictive value were above 90%. • Higher cut-offs would lead to a reduction in the sensitivity below 85% and an increase in the failure rate, especially for patients under 50 years.