Department of Women and Children's Health, School of Life Course Sciences, Faculty of Life Sciences and Medicine, King's College London, King's College Hospital NHS Foundation Trust, 4th Floor Golden Jubilee Wing, Denmark Hill, London, SE5 9RS, UK.
Neonatal Intensive Care Centre, King's College Hospital NHS Foundation Trust, London, UK.
Eur J Pediatr. 2023 Jul;182(7):3301-3306. doi: 10.1007/s00431-023-04991-5. Epub 2023 May 11.
Maternal cigarette smoking in pregnancy can adversely affect infant respiratory control. In utero nicotine exposure has been shown to blunt the infant ventilatory response to hypercapnia, which could increase the risk of sudden infant death syndrome. The potential impact of maternal second-hand smoke exposure, however, has not yet been determined. The aim of this study was to assess ventilatory response to added dead-space (inducing hypercapnia) in infants with second-hand smoke exposure during pregnancy, in infants whose mothers smoked and in controls (non-smoke exposed). Infants breathed through a face mask and specialised "tube-breathing" circuit, incorporating a dead space of 4.4 ml/kg body weight. The maximum minute ventilation (MMV) during added dead space breathing was determined and the time taken to achieve 63% of the MMV calculated (the time constant (TC) of the response). Infants were studied on the postnatal ward prior to discharge home. Thirty infants (ten in each group) were studied with a median gestational age of 39 [range 37-41] weeks, birthweight of 3.1 [2.2-4.0] kg, and postnatal age of 33 (21-62) h. The infants whose mothers had second-hand smoke exposure (median TC 42 s, p = 0.001), and the infants of cigarette smoking mothers (median TC 37 s, p = 0.002) had longer time constants than the controls (median TC 29 s). There was no significant difference between the TC of the infants whose mothers had second-hand smoke exposure and those whose mothers smoked (p = 0.112). Conclusion: Second-hand smoke exposure during pregnancy was associated with a delayed newborn ventilatory response. What is Known: • Maternal cigarette smoking in pregnancy can adversely affect infant respiratory control. • The potential impact of maternal second-hand smoke exposure, however, has not yet been determined. What is New: • We have assessed the ventilatory response to added dead-space (inducing hypercapnia) in newborns with second-hand smoke exposure during pregnancy, in infants whose mothers smoked, and in controls (non-smoke exposed). • Maternal second-hand smoke exposure, as well as maternal smoking, during pregnancy was associated with a delayed newborn ventilatory response.
孕妇吸烟会对婴儿的呼吸控制产生不利影响。宫内尼古丁暴露已被证明会使婴儿对高碳酸血症的通气反应迟钝，从而增加婴儿猝死综合征的风险。然而，母亲被动吸烟的潜在影响尚未确定。本研究的目的是评估在妊娠期间暴露于二手烟、母亲吸烟和对照组（未暴露于二手烟）的婴儿中，通过增加死腔（诱导高碳酸血症）来评估通气反应。婴儿通过面罩和专门的“管呼吸”回路呼吸，其中包含 4.4ml/kg 体重的死腔。确定了增加死腔呼吸时的最大分钟通气量（MMV），并计算达到 MMV 的 63%所需的时间（响应的时间常数（TC））。婴儿在出院回家前在新生儿病房进行研究。30 名婴儿（每组 10 名）接受研究，中位胎龄为 39 周[范围 37-41 周]，出生体重为 3.1kg[2.2-4.0kg]，产后年龄为 33 小时[21-62 小时]。母亲暴露于二手烟的婴儿（中位 TC 42s，p=0.001）和母亲吸烟的婴儿（中位 TC 37s，p=0.002）的时间常数比对照组长（中位 TC 29s）。母亲暴露于二手烟的婴儿的 TC 与母亲吸烟的婴儿无显著差异（p=0.112）。结论：妊娠期间暴露于二手烟与新生儿通气反应延迟有关。已知：·孕妇吸烟会对婴儿的呼吸控制产生不利影响。·然而，母亲被动吸烟的潜在影响尚未确定。新发现：·我们评估了在妊娠期间暴露于二手烟、母亲吸烟和对照组（未暴露于二手烟）的新生儿中，通过增加死腔（诱导高碳酸血症）来评估通气反应。·母亲在妊娠期间暴露于二手烟和吸烟与新生儿通气反应延迟有关。
