Contralateral surgery in patients scheduled for total thyroidectomy with initial loss or absence of signal during neural monitoring

BACKGROUND

Staged total thyroidectomy has been advised to prevent bilateral recurrent laryngeal nerve paralysis when loss of the signal from neural monitoring is observed after dissection of the initial thyroid lobe. This is supported by expert opinion but hard evidence is lacking. A lost signal can return during surgery or, even if it persists, its positive predictive value is only in the range 60-70 per cent. The aim of the present study was to investigate the clinical outcome of patients in whom total thyroidectomy was performed following loss of signal after dissection of the first thyroid lobe.

METHODS

This was a prospective observational study of adult patients scheduled for neural monitoring during total thyroidectomy. The prevalence of first-side absence or loss of signal was recorded. The contralateral thyroid lobe was approached routinely. The vagus and recurrent laryngeal nerves on the first side were retested during and at the end of the contralateral procedure.

RESULTS

Some 462 patients were included. Loss (32 patients) or initial absence (8) of signal at dissection of the first thyroid lobe was noted in 40 patients (8·7 per cent). Total thyroidectomy was completed in 29 patients, and a change of surgical strategy adopted in 11 patients with benign disease. At retesting, 15 of 37 initially silent nerves recovered electromyographic signal after a mean(s.d.) interval of 30(14) min. Postoperative vocal cord palsy/paresis was demonstrated in 24 of 40 patients. One patient developed a bilateral paresis that could be managed conservatively.

CONCLUSION

After an absence or loss of signal of the recurrent laryngeal nerve following dissection of the first thyroid lobe, contralateral thyroidectomy can be performed safely, avoiding the expense, psychological burden and potential complications of a second procedure.

Validation of the Apple Watch for Heart Rate Variability Measurements during Relax and Mental Stress in Healthy Subjects

Heart rate variability (HRV) analysis is a noninvasive tool widely used to assess autonomic nervous system state. The market for wearable devices that measure the heart rate has grown exponentially, as well as their potential use for healthcare and wellbeing applications. Still, there is a lack of validation of these devices. In particular, this work aims to validate the Apple Watch in terms of HRV derived from the RR interval series provided by the device, both in temporal (HRM (mean heart rate), SDNN, RMSSD and pNN50) and frequency (low and high frequency powers, LF and HF) domain. For this purpose, a database of 20 healthy volunteers subjected to relax and a mild cognitive stress was used. First, RR interval series provided by Apple Watch were validated using as reference the RR interval series provided by a Polar H7 using Bland-Altman plots and reliability and agreement coefficients. Then, HRV parameters derived from both RR interval series were compared and their ability to identify autonomic nervous system (ANS) response to mild cognitive stress was studied. Apple Watch measurements presented very good reliability and agreement (>0.9). RR interval series provided by Apple Watch contain gaps due to missing RR interval values (on average, 5 gaps per recording, lasting 6.5 s per gap). Temporal HRV indices were not significantly affected by the gaps. However, they produced a significant decrease in the LF and HF power. Despite these differences, HRV indices derived from the Apple Watch RR interval series were able to reflect changes induced by a mild mental stress, showing a significant decrease of HF power as well as RMSSD in stress with respect to relax, suggesting the potential use of HRV measurements derived from Apple Watch for stress monitoring.

Biometric Authentication Using the PPG: A Long-Term Feasibility Study

The photoplethysmogram (PPG) is a biomedical signal that can be used to estimate volumetric blood flow changes in the peripheral circulation. During the past few years, several works have been published in order to assess the potential for PPGs to be used in biometric authentication systems, but results are inconclusive. In this paper we perform an analysis of the feasibility of using the PPG as a realistic biometric alternative in the long term. Several feature extractors (based on the time domain and the Karhunen–Loève transform) and matching metrics (Manhattan and Euclidean distances) have been tested using four different PPG databases (PRRB, MIMIC-II, Berry, and Nonin). We show that the false match rate (FMR) and false non-match rate (FNMR) values remain constant in different time instances for a selected threshold, which is essential for using the PPG for biometric authentication purposes. On the other hand, obtained equal error rate (EER) values for signals recorded during the same session range from 1.0% for high-quality signals recorded in controlled conditions to 8% for those recorded in conditions closer to real-world scenarios. Moreover, in certain scenarios, EER values rise up to 23.2% for signals recorded over different days, signaling that performance degradation could take place with time.

An antimicrobial stewardship program reduces antimicrobial therapy duration and hospital stay in surgical wards

We report a quasi-experimental study of the implementation of an antimicrobial stewardship program in two surgical wards, with a pre-intervention period with just assessment of prescription and an intervention period with a prospective audit on antibiotic prescription model. There was a significant reduction of length of stay and the total days of antimicrobial administration. There were no differences in mortality between groups. The antimicrobial stewardship program led to the early detection of inappropriate empirical antibiotic treatment and was associated with a significant reduction in length of stay and the total duration of antimicrobial therapy.

DMSO affects Aβ1–40's conformation and interactions with aggregation inhibitors as revealed by NMR

DMSO alters Abeta's conformation and its recognition by inhibitors.