Face Masks and the Cardiorespiratory Response to Physical Activity in Health and Disease

Effect of Wearing Personal Protective Equipment (PPE) on CPR Quality in Times of the COVID-19 Pandemic-A Simulation, Randomised Crossover Trial

Cardiopulmonary resuscitation (CPR) is considered an aerosol-generating procedure. Consequently, COVID-19 resuscitation guidelines recommend the use of personal protective equipment (PPE) during resuscitation. In this simulation of randomised crossover trials, we investigated the influence of PPE on the quality of chest compressions (CCs). Thirty-four emergency medical service BLS-providers performed two 20 min CPR sequences (five 2 min cycles alternated by 2 min of rest) on manikins, once with and once without PPE, in a randomised order. The PPE was composed of a filtering facepiece 3 FFP3 mask, safety glasses, gloves and a long-sleeved gown. The primary outcome was defined as the difference between compression depth with and without PPE; secondary outcomes were defined as differences in CC rate, release and the number of effective CCs. The participants graded fatigue and performance, while generalised estimating equations (GEE) were used to analyse data. There was no significant difference in CC quality between sequences without and with PPE regarding depth (mean depth 54 ± 5 vs. 54 ± 6 mm respectively), rate (mean rate 119 ± 9 and 118 ± 6 compressions per minute), release (mean release 2 ± 2 vs. 2 ± 2 mm) and the number of effective CCs (43 ± 18 vs. 45 ± 17). The participants appraised higher fatigue when equipped with PPE in comparison to when equipped without PPE (p < 0.001), and lower performance was appraised when equipped with PPE in comparison to when equipped without PPE (p = 0.031). There is no negative effect of wearing PPE on the quality of CCs during CPR in comparison to not wearing PPE.

“You can leave your mask on”: effects on cardiopulmonary parameters of different airway protective masks at rest and during maximal exercise

During the COVID-19 pandemic, the use of protective masks has been essential to reduce contagions. However, public opinion is that there is an associated subjective shortness of breath. We evaluated cardiorespiratory parameters at rest and during maximal exertion to highlight any differences with the use of protective masks.

12 healthy subjects performed three identical cardiopulmonary exercise tests, one without wearing a protective mask, one wearing a surgical mask and one with a filtering face piece particles class 2 (FFP2) mask. Dyspnoea was assessed using the Borg scale. Standard pulmonary function tests were also performed.

All the subjects (40.8±12.4 years; six male) completed the protocol with no adverse events. Spirometry showed a progressive reduction of forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC) from no mask to surgical to FFP2 (FEV1: 3.94±0.91 L, 3.23±0.81 L, 2.94±0.98 L; FVC: 4.70±1.21 L, 3.77±1.02 L, 3.52±1.21 L; p<0.001). Rest ventilation, O2 uptake (V˙O2) and CO2 production (V˙CO2) were progressively lower, with a reduction in respiratory rate. At peak exercise, subjects had a progressively higher Borg scale when wearing surgical and FFP2 masks. Accordingly, at peak exercise, V˙O2 (31.0±23.4 mL·kg−1·min−1, 27.5±6.9 mL·kg−1·min−1, 28.2±8.8 mL·kg−1·min−1; p=0.001), ventilation (92±26 L, 76±22 L, 72±21 L; p=0.003), respiratory rate (42±8 breaths·min−1, 38±5 breaths·min−1, 37±4 breaths·min−1; p=0.04) and tidal volume (2.28±0.72 L, 2.05±0.60 L, 1.96±0.65 L; p=0.001) were gradually lower. There was no significant difference in oxygen saturation.

Protective masks are associated with significant but modest worsening of spirometry and cardiorespiratory parameters at rest and peak exercise. The effect is driven by a ventilation reduction due to increased airflow resistance. However, because exercise ventilatory limitation is far from being reached, their use is safe even during maximal exercise, with a slight reduction in performance.