A Study On The Etiology And Mechanism Of Cough Syncope

BackgroundCough is an important defensive reflex of the body,and healthy people may cough.Mild and infrequent cough will not only cause no harm to the body,but also have the benefit for promoting the discharge of sputum and foreign bodies.However,severe cough or frequent cough not only affects the patient's work and life,but also promotes the spread of pathogens and damages the elasticity of lung tissue.In clinical work,a little of patients experienced complete loss of consciousness after coughing.Complete loss of consciousness caused by cough is called cough syncope.What are the characteristics of these patients,and what are mechanisms of cough syncope?Looking up relevant literature at home and abroad,we found that literatures about cough syncope are mainly case reports.The only few studies were conducted by foreign scholars on a few cases,a dozen cases,and a maximum of tens of patients.There are lack domestic summaries of the clinical features of cough syncope,lack of etiology and mechanism of cough syncope.Therefore,we summaried the clinical features of 31 patients of cough syncope admitted in our hospital,and explored etiology and mechanism of cough syncope,in order to improve the understanding of cough syncope.ObjectivesSummarize the clinical features of patients with cough syncope,and explore etiology and mechanisms of cough syncope.MethodsSelected recurrent cough syncope?referring to two or more coughs or syncope immediately after cough?at the ward of the Second Affiliated Hospital of Zhengzhou University from October 2015 to December 2017.31 patients in the observation group were subjects of the control group.62 patients with the main or only symptom of"cough"matching the age,gender,body mass index,smoking status with observation group were the subjects of the control group.All study subjects performed detailed medical history collection,comprehensive physical examination,and necessary auxiliary examinations prior to enrollment,excluding cardiac syncope,neurogenic syncope,and epileptic seizures.Results1.General information on patients of the observation groupIn 31 patients with cough syncope,there were 22 males and 9 females;the average age was 40.78±11.24 years,4 patients were 18-35 years old,24 patients were 36-60years old,and 3 patients were 60-75 years old,accounting for 12.9%of the total.77.4%,9.6%;mean BMI was 26.32±3.94 kg/m²,25 patients with BMI>24 kg/m²,accounting for 80.6%,23 patients had smoking history,accounting for 64.5%.2.The basic diseases between two groups of patientsIn the observation group,13 patients had a history of hypertension,8 patients had a history of diabetes,7 patients had a history of heart disease,11 patients had a history of cerebrovascular disease.In the control group,15 patients had a history of hypertension,15 patients had a history of diabetes,9 patients had a history of heart disease,11 patients had a history of cerebrovascular disease.3 Results of HUTTIn the observation group,all patients underwent BHUTT,22 patients underwent SNHUTT,and all patients in the control group underwent BHUTT and SNHUTT.In the observation group,there were 9 patients positive in BHUTT and 3 patients positive in SNHUTT.HUTT total positive rate was 38.7%.In the control group,there was no patient positive in HUTT.4 The effect of cough on hemodynamicsAfter cough,the SBP and DBP of the syncope subgroup respectively decreased by 57±25 mmHg and 32±19 mmHg,the HR increased by 21±9 beats/min,and the SpO₂decreased by 6.4±4.8%.The SBP and DBP of the pre-syncope subgroup decreased by43±13 mmHg and 27±11 mmHg,the HR increased by 11±7 beats/min,and the SpO₂decreased by 4.7±3.2%.The SBP and DBP of the asymptomatic subgroup respectivelyd ecreased by 27±14 mmHg and 8.3±5.5mmHg,and the HR increased by8.0±3.7 beats/min,SpO₂ decreased by?5.4±4.1?%.The SBP and DBP in the control group decreased by an average of 10±6 mmHg and 8.1±5.3 mmHg,respectively,and the HR increased by an average of 7.2±4.1 beats/min,and the SpO₂ decreased by an average of?4.6±3.3?%.Conclusions1 Overweight middle-aged men with a history of smoking are prone to cough syncope.2 Patients with hypertension,cardiovascular disease,and cerebrovascular disease are prone to cough syncope.3 Head-Up Tilt Test is recommended for patients with cough syncope to determine if there is autonomic dysfunction.4 Patients with cough syncope show a marked decrease in blood pressure during cough,and it is assumed that the decrease in blood pressure is the direct cause of cough syncope.