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iNO as Salvage Treatment of Hypoxemia After TAAD Surgery

Conditions
Type A Aortic Dissection
Interventions
Drug: inhaled nitric oxide
Device: PEEP
Registration Number
NCT04032366
Lead Sponsor
Shanghai Zhongshan Hospital
Brief Summary

The purpose of this study was to clarify the possible mechanism of hypoxemia after surgical treatment of type A acute aortic dissection and the possible mechanism of the treatment role of inhaled nitric oxide in refractory hypoxemia.

Detailed Description

The investigators' previous study has stressed that inhaled nitric oxide therapy might play an ameliorative role in patients with refractory hypoxemia after surgical treatment of type A acute aortic dissection. The possible reason might be the decreasing of intrapulmonary shunt because previous studies showed that inhaled nitric oxide could decrease intrapulmonary shunt by selectively dilating the pulmonary vessels in ventilated areas. As a result, the investigators designed this observational study to calculate the intrapulmonary shunt before and after inhaled nitric oxide therapy. Intrapulmonary shunt was calculated from oxygen content (CO2) of different sites ( artery, mixed venous, alveolar capillary) by Fick equation:(CaO2-CcO2)/(CvO2-CcO2). A FiO2 of 1.0 and tidal volume of 6\~8 ml/kg were chosen. Oxygen content was calculated from hemoglobin (Hb), oxygen saturation (SO2) and oxygen partial pressure (PO2) by the following equation: CO2 = 1.34\*Hb\*SO2 + 0,0031\*PO2. PaO2, SaO2, PvO2 and SvO2 were measured from arterial and mixed venous blood samples taken from the radial arterial catheter and from the pulmonary artery catheter. ScO2 was estimated to be 1.0 with a FiO2 of 100%. PcO2 was considered to be the same as PAO2 (partial pressure of oxygen in the alveoli), and was calculated from the alveolar gas equation with PAO2 = \[(atmospheric pressure - 47) \* (FiO2)\] - PaCO2/0.8.Other variables such as hemodynamic variables from pulmonary artery catheter were also collected.

Recruitment & Eligibility

Status
UNKNOWN
Sex
All
Target Recruitment
20
Inclusion Criteria
  • Adult
  • Type A aortic dissection;
  • After surgery;
  • P/F ratio ≤ 200mmHg
Exclusion Criteria
  • Intracardiac shunt;
  • Contradiction of PAC;
  • Chronic pulmonary diseases before surgery;
  • ECMO;
  • Anticipation of death within 48 hours after operation;

Study & Design

Study Type
OBSERVATIONAL
Study Design
Not specified
Arm && Interventions
GroupInterventionDescription
PEEP 10PEEPpost-surgical type A acute aortic dissection patients was ventilated with a PEEP of 10cm H2O, without inhaled nitric oxide
PEEP 10inhaled nitric oxidepost-surgical type A acute aortic dissection patients was ventilated with a PEEP of 10cm H2O, without inhaled nitric oxide
PEEP 5 +iNOinhaled nitric oxidepost-surgical type A acute aortic dissection patients was ventilated with a PEEP of 5cm H2O, with inhaled nitric oxide
PEEP 5 +iNOPEEPpost-surgical type A acute aortic dissection patients was ventilated with a PEEP of 5cm H2O, with inhaled nitric oxide
Primary Outcome Measures
NameTimeMethod
Intrapulmonary shunt with a PEEP of 5 cm H2O6 to 24 hours after surgery

intrapulmonary shunt calculated by Fick equation with a PEEP of 5 cm H2O

Intrapulmonary shunt with a PEEP of 10 cm H2O30 minutes after increasing PEEP to 10cm H2O

intrapulmonary shunt calculated by Fick equation with a PEEP of 10 cm H2O

Intrapulmonary shunt with inhaled nitric oxide and a PEEP of 5 cm H2O30 minutes after decreasing PEEP to 5cm H2O

intrapulmonary shunt calculated by Fick equation with inhaled nitric oxide and a PEEP of 5 cm H2O

Intrapulmonary shunt with a PEEP of 10 cm H2O and inhaled nitric oxide30 minutes after inhaling nitric oxide

intrapulmonary shunt calculated by Fick equation with a PEEP of 10 cm H2O and inhaled nitric oxide

Secondary Outcome Measures
NameTimeMethod
cardiac output collected from PAC with a PEEP of 10cm H2O30 minutes after increasing PEEP to 10cm H2O

cardiac output in L/min

cardiac output collected from PAC with a PEEP of 5 cm H2O6 to 24 hours after surgery

cardiac output in L/min

pulmonary artery pressure collected from PAC with a PEEP of 5 cm H2O6 to 24 hours after surgery

pulmonary artery pressure in mmHg

pulmonary artery wedge pressure collected from PAC with a PEEP of 5 cm H2O6 to 24 hours after surgery

pulmonary artery wedge pressure in mmHg

pulmonary artery wedge pressure collected from PAC with a PEEP of 10 cm H2O and inhaled nitric oxide30 minutes after inhaling nitric oxide

pulmonary artery wedge pressure in mmHg

pulmonary artery pressure collected from PAC with inhaled nitric oxide and a PEEP of 5 cm H2O30 minutes after decreasing PEEP to 5 cm H2O

pulmonary artery pressure in mmHg

pulmonary artery wedge pressure collected from PAC with inhaled nitric oxide and a PEEP of 5 cm H2O30 minutes after decreasing PEEP to 5 cm H2O

pulmonary artery wedge pressure in mmHg, etc

pulmonary artery wedge pressure collected from PAC with a PEEP of 10 cm H2O30 minutes after increasing PEEP to 10cm H2O

pulmonary artery wedge pressure in mmHg

cardiac output collected from PAC with a PEEP of 10 cm H2O and inhaled nitric oxide30 minutes after inhaling nitric oxide

cardiac output in L/min

cardiac output collected from PAC with inhaled nitric oxide and a PEEP of 5 cm H2O30 minutes after decreasing PEEP to 5 cm H2O

cardiac output in L/min

pulmonary artery pressure collected from PAC with a PEEP of 10 cm H2O30 minutes after increasing PEEP to 10cm H2O

pulmonary artery pressure in mmHg

pulmonary artery pressure collected from PAC with a PEEP of 10 cm H2O and inhaled nitric oxide30 minutes after inhaling nitric oxide

pulmonary artery pressure in mmHg

Trial Locations

Locations (1)

Zhongshan hospital Fudan University

🇨🇳

Shanghai, Shanghai, China

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