Acute lung inflammatory response and injury after hemorrhagic shock are more severe in postpartum rabbits*

Abstract

After hemorrhage and resuscitation, obstetric rabbits had significantly shorter survival time and more severe lung injury than nonobstetric rabbits. The mechanism may be through upregulation of the signal transductions of the nuclear factor-κB pathways.

Estrogen-mediated impairment of macrophageal uptake of environmental TiO2particles to explain inflammatory effect of TiO2on airways during pregnancy

“…Epidemiological data suggest pregnancy increases influenza mortality (Memoli et al, 2012;Rasmussen et al, 2008), exacerbates asthma (Kircher et al, 2002), and leads to lung injury (Sheng et al, 2012) and deleterious effects of stress (Coussons-Read et al, 2007). This risk extends to commonplace environmental exposures like inert respirable particulates without soluble components considered non-toxic.…”

Acute Respiratory Distress Syndrome in Pregnancy: Updates in Principles and Practice

“…18 A "two-hit" model of ARDS in pregnancy has been proposed, suggesting that a proinflammatory state observed in pregnancy (and during the postpartum period) primes subjects for a robust inflammatory response to a lesser "second hit" or insult resulting in ARDS. 19,20 Various physiological changes occur during pregnancy, including decreased lower esophageal sphincter tone, delayed gastric emptying, and increased intraabdominal pressure during labor and delivery; this can predispose pregnant patients to chemical pneumonitis through aspiration of gastric contents. 21 Sepsis because of pyelonephritis is a risk factor for ARDS in up to 7% of pregnant patients.…”

“…With respect to pregnancy, nonobstetric conditions leading to ARDS include pneumonia, sepsis, viral lung infections [influenza, severe acute respiratory syndrome coronavirus 2 (SARS‑CoV‑2)], blood product transfusion, intracerebral hemorrhage, and trauma 18. A “two-hit” model of ARDS in pregnancy has been proposed, suggesting that a proinflammatory state observed in pregnancy (and during the postpartum period) primes subjects for a robust inflammatory response to a lesser “second hit” or insult resulting in ARDS 19,20. Various physiological changes occur during pregnancy, including decreased lower esophageal sphincter tone, delayed gastric emptying, and increased intraabdominal pressure during labor and delivery; this can predispose pregnant patients to chemical pneumonitis through aspiration of gastric contents 21.…”

“…22 Yet, a retrospective study from Southern California reported the frequency of pyelonephritis leading to ARDS to be 0.5%, thereby suggesting that prevention and treatment of complicated urinary tract infections may partly explain the decrease. 23 In the pregnant patient, viral lower respiratory tract infections are a nonobstetric risk factor for ARDS that include influenza A (H1N1), SARS-CoV-1 (middle east respiratory syndrome), and SARS-CoV-2 [coronavirus disease 2019 (COVID- 19)]. [24][25][26] Investigators have reported that a higher risk for influenzaassociated complications in pregnant patients that includes hospitalization, ICU admission, ARDS, and death.…”

“…59 Retrospective case series concerning mechanical ventilation during pregnancy for acute hypoxemic respiratory failure have described epidemiology, causes, and maternal-fetal survival. [16][17][18][19]22 Unfortunately, there is limited data regarding physiological or clinical outcomes with use of different ventilation strategies in pregnant patients with acute respiratory failure.…”