Blood flow effects of percutaneous peripheral nerve stimulation. A blinded, randomized clinical trial.

BACKGROUND: The vasculature function is mainly regulated by the autonomic nervous system. Importantly, the sensory-motor nervous system also innervates peripheral vessels and has the capacity to modulate vascular tone. Here we investigated the effects of electrical stimulation of a mixed nerve trunk on blood flow in deep arteries and muscle perfusion. Our hypothesis is that stimulation of a mixed nerve can modify blood flow. METHODS: Twenty-nine healthy participants were included into a randomized-crossover and blinded clinical trial. Each subject received a placebo and two percutaneous peripheral nerve stimulation (pPNS) protocols on the median nerve: Pain Threshold continuous Low Frequency (PT-cLF) and Sensory Threshold burst High Frequency (ST-bHF). Blood flow was then assessed bilaterally using Power Doppler Ultrasonography at the main arteries of the arm, and blood perfusion at the forearm muscles. Afterwards, blood flow was quantified using a semi-automatized software, freely shared here. RESULTS: Placebo, consisting in needle insertion, produced an immediate and generalized reduction on peak systolic velocity in all arteries. Although nerve stimulation produced mainly no effects, some significant differences were found: both protocols increased the relative perfusion area of the forearm muscles, the ST-bHF protocol prevented the reduction in peak systolic velocity and TAMEAN of the radial artery produced by the control protocol and PT-cLF produced a TAMEAN reduction of the ulnar artery. CONCLUSIONS: Therefore, the arterial blood flow in the arm is mainly impervious to the electrical stimulation of the median nerve, composed by autonomic and sensory-motor axons, although it produces mild modifications in the forearm muscles perfusion.

Impact of the COVID-19 Pandemic on the Work Activity of Spanish Physical Therapists and Their Response to Vaccination.

Due to the COVID-19 pandemic, physical therapists have had to adopt a set of specific protection measures, which have had an impact on their clinical activity and economy. The objective was to evaluate the impact of the COVID-19 pandemic on the work of Spanish physical therapists, as well as their attitudes and predisposition to vaccination. An online questionnaire was divided into five sections: (1) demographic and professional data; (2) labor impact; (3) precautions and infection-control measures; (4) economic impact; and (5) vaccine acceptance and adverse effects. Of the 666 participants, 62.1% showed a reduction in their working hours motivated by: fear of infection (p = 0.007), financial issues (p = 0.002) and being in quarantine or isolation (p < 0.001). Of these, 36.4% were forced to close the clinic, 62.7% requested help from the government, but only 12.04% mentioned that it was adequate. The main prevention measures adopted were the use of gels and masks and, in the private sector, disinfection with ozone or ultraviolet light (p < 0.05). The acceptance of the vaccine was high, 87.5%, being lower among the group over 40 years of age, self-employed, widowed or separated. More adverse effects were mentioned after receiving the AstraZeneca-Oxford vaccine, compared to Pfizer-BioNTech or Moderna. In conclusion, this study assessed for the first time that the COVID-19 pandemic in Spain had a negative impact on work and finances of physical therapists. The vaccine was widely accepted, in part by the economic impact that an infection in the work setting could signify.