We investigated the effects of different CO2 tensions on oxygenation, pulmonary blood flow(Qp), cerebral blood flow, and systemic blood flow(Qs) after the bidirectional superior cavopulmonary anastomosis (BCPA). Hypox...We investigated the effects of different CO2 tensions on oxygenation, pulmonary blood flow(Qp), cerebral blood flow, and systemic blood flow(Qs) after the bidirectional superior cavopulmonary anastomosis (BCPA). Hypoxemia refractory to management of a high pulmonary vascular resistance index(PVRI) may complicate recovery from the BCPA. After BCPA, CO2 was added to the inspired gas of mechanically ventilated patients. The Qp, Qs, PVRI, and systemic vascular resistance index(SVRI) were calculated from oxygen consumption, intravascular pressures, and oxygen saturations. Cerebral blood flow was estimated by near infrared spectroscopy and transcranial Doppler. In nine patients(median age 7.1, range 2 to 23 months), arterial oxygen tension increased significantly (p< 0.005) from 36±6 mm Hg to 44±6 to 50±7 mm Hg at arterial carbon dioxide tensions (PaCO2) of 35, 45, and 55 mm Hg, respectively and decreased to 40±8 mm Hg at PaCO2 40 mm Hg. At a PaCO2 of 55 and 45 compared with 35 mm Hg, Qp, cerebral blood flow, and Qs increased significantly, PVRI, Qp/Qs, and the ratio of Qp to inferior vena caval blood flow were unchanged, but SVRI decreased. We have demonstrated that after the BCPA, systemic oxygenation, Qp, Qs, and cerebral blood flow increased and SVRI decreased at CO2 tensions of 45 and 55 mm Hg compared with 35 mm Hg. We suggest that hypoxemia after the BCPA is ameliorated by a higher PaCO2 and that low PaCO2 or alkalosis may be detrimental. Hypercarbic management strategies may allow earlier progression to the BCPA, which may contribute to reducing the interval morbidity in patients with a functional single ventricle.展开更多
Background: Children with multiple severe disabilities cannot be spontaneously physically active and therefore lack the ventilatory stimulation of physical activity. They often produce large quantities of airway mucus...Background: Children with multiple severe disabilities cannot be spontaneously physically active and therefore lack the ventilatory stimulation of physical activity. They often produce large quantities of airway mucus, which they have difficulty to evacuate on their own. The accumulation of mucus may lead to respiratory insufficiency. Aim: To investigate whether chest physiotherapy with positive expiratory pressure (PEP)-could improve the blood oxygen tension (PO2) and/or decrease carbon dioxide tension (PCO2) in severely disabled children with airway mucus accumulation. Methods: Eighteen disabled children (mean age 7.5 y, SD 4.3, range 1.7-17.8 y) participated in the study. Transcutaneous (tc) PO2, tcPCO2 and respiratory rate (RR) were recorded before and after PEP treatment. The reproducibility of the effect of the treatment was tested by repeating the recordings. Results: The mean tcPO2 increased 1.0 kPa (range -0.2 to 3.4 kPa) immediately after PEP treatment (p=0.0001). No significant changes in tcPCO2 or RR were noted. The reproducibility of the effect of PEP treatment was good, with a significant increase in tcPO2 at all retests. All children accepted the treatment well. Conclusion: PEP increases blood oxygen tension immediately after treatment in severely disabled children with airway mucus accumulation. Long-term effects remain to be proven.展开更多
This study reports for the first time the use of a respiratory function monitor in a prospective observational cohort of ventilated babies during transport. All 17 babies achieved target transcutaneous carbon dioxide ...This study reports for the first time the use of a respiratory function monitor in a prospective observational cohort of ventilated babies during transport. All 17 babies achieved target transcutaneous carbon dioxide tension within 15 minutes. Fifteen babies had improved ventilation with changes guided by the respiratory function monitor. The monitor was easy to use and useful.展开更多
文摘We investigated the effects of different CO2 tensions on oxygenation, pulmonary blood flow(Qp), cerebral blood flow, and systemic blood flow(Qs) after the bidirectional superior cavopulmonary anastomosis (BCPA). Hypoxemia refractory to management of a high pulmonary vascular resistance index(PVRI) may complicate recovery from the BCPA. After BCPA, CO2 was added to the inspired gas of mechanically ventilated patients. The Qp, Qs, PVRI, and systemic vascular resistance index(SVRI) were calculated from oxygen consumption, intravascular pressures, and oxygen saturations. Cerebral blood flow was estimated by near infrared spectroscopy and transcranial Doppler. In nine patients(median age 7.1, range 2 to 23 months), arterial oxygen tension increased significantly (p< 0.005) from 36±6 mm Hg to 44±6 to 50±7 mm Hg at arterial carbon dioxide tensions (PaCO2) of 35, 45, and 55 mm Hg, respectively and decreased to 40±8 mm Hg at PaCO2 40 mm Hg. At a PaCO2 of 55 and 45 compared with 35 mm Hg, Qp, cerebral blood flow, and Qs increased significantly, PVRI, Qp/Qs, and the ratio of Qp to inferior vena caval blood flow were unchanged, but SVRI decreased. We have demonstrated that after the BCPA, systemic oxygenation, Qp, Qs, and cerebral blood flow increased and SVRI decreased at CO2 tensions of 45 and 55 mm Hg compared with 35 mm Hg. We suggest that hypoxemia after the BCPA is ameliorated by a higher PaCO2 and that low PaCO2 or alkalosis may be detrimental. Hypercarbic management strategies may allow earlier progression to the BCPA, which may contribute to reducing the interval morbidity in patients with a functional single ventricle.
文摘Background: Children with multiple severe disabilities cannot be spontaneously physically active and therefore lack the ventilatory stimulation of physical activity. They often produce large quantities of airway mucus, which they have difficulty to evacuate on their own. The accumulation of mucus may lead to respiratory insufficiency. Aim: To investigate whether chest physiotherapy with positive expiratory pressure (PEP)-could improve the blood oxygen tension (PO2) and/or decrease carbon dioxide tension (PCO2) in severely disabled children with airway mucus accumulation. Methods: Eighteen disabled children (mean age 7.5 y, SD 4.3, range 1.7-17.8 y) participated in the study. Transcutaneous (tc) PO2, tcPCO2 and respiratory rate (RR) were recorded before and after PEP treatment. The reproducibility of the effect of the treatment was tested by repeating the recordings. Results: The mean tcPO2 increased 1.0 kPa (range -0.2 to 3.4 kPa) immediately after PEP treatment (p=0.0001). No significant changes in tcPCO2 or RR were noted. The reproducibility of the effect of PEP treatment was good, with a significant increase in tcPO2 at all retests. All children accepted the treatment well. Conclusion: PEP increases blood oxygen tension immediately after treatment in severely disabled children with airway mucus accumulation. Long-term effects remain to be proven.
文摘This study reports for the first time the use of a respiratory function monitor in a prospective observational cohort of ventilated babies during transport. All 17 babies achieved target transcutaneous carbon dioxide tension within 15 minutes. Fifteen babies had improved ventilation with changes guided by the respiratory function monitor. The monitor was easy to use and useful.
