Breathing at Extremes

Associations with covid-19 hospitalisation amongst 406,793 adults: the UK Biobank prospective cohort study

“…29 Obesity decreases key operating lung volumes and this effect appears particularly pronounced in men. 30 We observed a strong association with increased risk of severe covid-19 in ever smokers, indicating a harmful impact of smoking on the risk of developing severe covid-19. This risk was mainly observed in the former rather than current smokers; this could be related to the low prevalence of current smokers in this cohort, or that participants still smoking represent a healthier subset of all prior smokers in that some former smokers may have given up due to poorer health.…”

“…29 Obesity decreases key operating lung volumes and this effect appears particularly pronounced in men. 30…”

Cesarean Delivery in a Patient With Body Mass Index Over 100: Continuous Spinal Anesthesia in Two Consecutive Deliveries

“…Her habitus caused respiratory difficulty in the usual surgical position, so it was important to discuss surgical positioning and the adjusted operative approach with the surgeon prior to bringing her to the OR. Restrictive ventilation is expected with very severe obesity and is further exacerbated by supine positioning [ 13 ]. Her semi-upright positioning was surgically feasible using a supraumbilical midline skin incision and classical uterine incision, as described in a previous case series [ 10 ].…”

“…As mentioned, this patient could not breathe comfortably in the supine position even prior to the pregnancy. Restricted ventilation is expected to be exacerbated by surgical retraction and supine positioning, which we feared would induce respiratory distress requiring CPAP or intubation [ 13 ]. With these factors in mind, we opted for a gradual spinal blockade while monitoring her breathing pattern and slowly lowering her into her flattest-tolerated position.…”

Exercise ventilation and dyspnea in the obese patient with chronic obstructive pulmonary disease: “how much” versus “how well”

“…13 In more severe obesity, however, TLC may decrease, potentially decreasing IC despite a low FRC. 14 To make things even more complex, fat distribution has a major impact on these inter-relationships since the android/ central pattern of obesity has a larger lowering effect on lung volumes (including TLC) compared to the gynecoid/peripheral pattern. 15 Breathing at excessively low lung volumes, in turn, may predispose to the closure of small airways, leading to ventilation/perfusion mismatch and gas trapping.…”