Study On The Application Of Modified Mask Combined With HFNC In Patients With Postoperative Hypoxemia After Cardiac Surgery

Objective:To design a modified mask that can increase the oxygen storage space during nasal catheter oxygen inhalation,develop a modified mask combined with HFNC oxygen therapy intervention program,and explore the efficacy and safety of this program in patients with hypoxemia after cardiac surgery.To provide a reference for optimizing oxygen therapy intervention in patients with hypoxemia after cardiac surgery.Methods:1.The design of an improved mask based on innovative and evidence-based concepts and the preliminary formulation of an oxygen therapy intervention plan.Based on the current status of HFNC oxygen therapy intervention in patients with hypoxemia after cardiac surgery at domestic and foreign,the existing masks were modified to increase oxygen storage space,and evidence related to HFNC oxygen therapy intervention in patients with hypoxemia after tracheal intubation was retrieved.The quality evaluation,grading,extraction,and integration were conducted to form the first draft of the modified mask combined with HFNC oxygen therapy intervention plan.Using the purposive sampling method,experts from different disciplines were selected to demonstrate the preliminary draft of the plan,and the feasibility of the plan was discussed from the perspectives of different disciplines and stakeholders.The preliminary draft of the plan was revised to finally determine the oxygen therapy intervention plan.2.Quasi-experimental study.A whole-group sampling method was adopted to select 68 adult patients admitted to a tertiary care hospital in Bengbu from January 1,2021 to March 1,2022 who underwent cardiac surgery and developed hypoxemia after postoperative extubation as the study subjects.In chronological order of admission,patients admitted from January 2021 to July 2021 were designated as the control group and patients admitted from August 2021 to March 2022 were designated as the observation group.Patients in the control group were treated with HFNC and patients in the observation group were treated with a modified mask combined with HFNC oxygen therapy.Arterial blood was extracted from the patients’radial artery catheters before treatment and 0.5,1,6,24 hours after treatment for blood gas analysis;And closely monitor their respiratory physiological parameters[pH,arterial partial pressure of oxygen（PaO₂）,arterial partial pressure of carbon dioxide（PaCO₂）,blood oxygen saturation（SpO₂）,oxygenation index（PaO₂/FiO₂）,respiratory frequency（RR）],circulatory hemodynamic parameters[heart rate（HR）,mean arterial pressure（MAP）,blood lactic acid（Lac）],early prediction indicators of oxygen therapy results[ROX index（ratio of SpO₂/FiO₂to RR）,and ROX-HR index（ratio of ROX index to HR multiplied by a coefficient of 100）];Echocardiography was performed to assess LVEF at 6h and 24h after treatment;Nurses used the comfort digital rating scale NRS and Borg dyspnea scale to evaluate the two groups of patients before and 0.5,1,6,and 24 hours after treatment;After 24 hours of treatment,follow up the incidence of mechanical ventilation reintubation rate,HFNC usage duration,ICU stay time and total hospital stay,pulmonary infection rate,hospital mortality,and related complications（including skin crush,stomach bloating,pneumothorax,etc.）between the two groups,and compare the differences in the observation indicators between the two groups.Results:1.The improved mask combined with HFNC oxygen therapy intervention plan based on evidence-based best recommendations includes three aspects:early evaluation of oxygen therapy,management of oxygen therapy,and evaluation of oxygen therapy effectiveness,forming three first level items,11 second level items,and 31 third level items.2.In the application of the modified mask combined with HFNC oxygen therapy scheme,the baseline data of patients in the observation group and the control group were comparable,and the difference was not statistically significant（P>0.05）.3.Respiratory physiological parameters:After treatment,compared with before treatment,the partial pressure of arterial blood oxygen（PaO₂）in the observation group increased（96.9±19.9）,the oxygenation index（PaO₂/FiO₂）increased（122.7±34.0）,and the respiratory rate（RR）decreased（18.1±3.1）,with a statistically significant difference（P<0.05）.At 0.5h,1h,6h,and 24h after treatment,the arterial partial pressure of oxygen（PaO₂）and oxygenation index（PaO₂/FiO₂）in the observation group were significantly higher than those in the control group（P<0.05）,and the respiratory rate（RR）was lower than that in the control group,with a statistically significant difference（P<0.05）.There was no significant difference between the two groups in pH and arterial partial pressure of carbon dioxide（PaCO₂）（P>0.05）.4.Circulating hemodynamic parameters:At 0.5h,1h,6h,and 24h after treatment,the average arterial pressure（MAP）of patients in the observation group was significantly higher than that in the control group,with a statistically significant difference（P<0.05）.There was no significant difference in heart rate（HR）,blood lactic acid（Lac）,and left ventricular ejection fraction（LVEF）between the two groups（P>0.05）.5.Early predictive indicators of oxygen therapy outcomes in the two groups:At0.5h,1h,6h,and 24h after treatment,the early predictive ROX index and ROX-HR index in the observation group were significantly higher than those in the control group,with a statistically significant difference（P<0.05）.6.Borg score and NRS score:The Borg score（0.4±0.4）and NRS score（2.0±0.7）of patients in the observation group after treatment were lower than those before treatment,with a statistically significant difference（P<0.05）.At 1h,6h,and 24h after treatment,the Borg scores of patients in the observation group were lower than those in the control group,with a statistically significant difference（P<0.05）.There was no significant difference in NRS scores between the two groups（P>0.05）.7.Outcome and prognosis:The rate of mechanical ventilation reintubation,the duration of HFNC use（36.6±11.3）,and the ICU stay time（3.9±1.6）in the observation group were significantly lower than those in the control group（P<0.05）;There was no significant difference between the two groups in terms of total hospital stay,incidence of pulmonary infection,hospital mortality,and related complications（including skin crush,bloating,pneumothorax,etc.）（P>0.05）.8.Analysis of subgroups in the observation group:The patients in the observation group were divided into two groups according to whether they underwent extracorporeal circulation during surgery,and were divided into two groups according to the preoperative cardiac function grading.There was no significant difference between the two groups in PaO₂changes,LVEF changes,RR changes,and HR changes,with no statistical significance（P>0.05）.Conclusion:Conclusion:1.The improved design of the mask increases the oxygen storage space,improves the oxygen concentration of the mixed gas inhaled by the patient,thereby alleviating the hypoxia state,and can provide more treatment options for clinical patients with hypoxemia.2.The modified mask combined with HFNC oxygen therapy scheme is based on the best evidence and expert evaluation,combined with existing clinical realities,and can provide a reference for oxygen therapy for patients with hypoxia after cardiac surgery.3.In patients with hypoxemia after extubation after cardiac surgery,the use of a modified mask combined with HFNC oxygen therapy regimen can improve the patient’s oxygen uptake concentration,thereby increasing PaO₂,improving the treatment effectiveness of patients with hypoxemia,and reducing the duration of HFNC use and the rate of mechanical ventilation re intubation.