The Clinical Application Of Uniblocker Tube In One Lung Ventilation

The development and improvement of thoracic surgery have also benefited from the progress of thoracic anesthesia.One-lung ventilation（OLV）is required during most thoracic surgeries to facilitate surgical visualization by collapsing the lung and avoid the contamination of healthy lung by secretions or blood in the operative side lung.The development and progress of OLV technology has provided favorable operating conditions for some conventional chest operations,such as radical esophageal cancer resections and radical lung cancer resections,and also made possible for some sort of operations such as massive mediastinal masses resection,reconstruction of trachea,bronchoplasty,sleeve resection of bronchus and plastic carinoplasty.In recent years,minimally invasive surgeries,such as TV assisted thoracoscopic surgery and small incision coronary artery bypass surgery have been rapidly developed,which raise higher requirements for OLV technology.There are three common methods for OLV:Double-lumem tubes（DLTs）,single lumem tubes（SLTs）and Bronchial blocker（BBs）.DLTs are the most commonly used devices for OLV,especially the left side double-lumem tube（LDLT）,however,compared with SLTs,DLTs are associated with some limitations,such as difficulty with intubation in patients with difficult airway and increasing the risk for potential traumatic injury,leading to sore throat and hoarseness postoperative.Furthermore,if patients require ventilation support after surgery,DLTs need to be replaced by SLTs postoperative.BBs,such as Univent blocker,Arndt blocker,Cohen blocker,Uniblocker,EZ blocker,and Coopdech blocker,have more advantages than the DLTs:easier insertion,especially in patients with difficult airway and no need to exchange the tube when mechanical ventilation is required after surgery.The most of BBs are placed under direct vision of Fiberoptic bronchoscopy（FOB）,However,Even under direct vision of FOB,the placement of BBs still requires more time compared with the LDLT.Furthermore,FOB has many disadvantages.First,FOB is too expensive to be used widely in anesthesia departments and many anesthesia departments of hospitals in remote areas lack suitable sizes of FOB for the intubation of BBs;Second,FOB should be sterilized before use which increases the financial burden on patients;Third,secretions and blood inside the trachea and anatomic distortion may make the confirmation of BBs position more difficult and many anesthesiologists lack of training and are unfamiliar with the FOB.Therefore,anesthesiologists have been attempting to improve the technique of intubation of the BBs.So,we designed a new simple method of BBs placement by extraluminal technique supported by trachea length measurement according chest CT images.Therefore,the first part and second part of this study were to evaluate the safety and effectiveness of this new intubation method of Uniblocker;third part was to compare the efficacy and adverse effects of the Uniblocker and LDLT for OLV under the guidance of chest computerized tomography（CT）.The contents of each part were summarized as follows:Part one A comparison of extraluminal and intraluminal use of the Uniblocker in the left side thoracic surgeryObjective:The aim of this study was to assess the feasibility and the safety issues concerning extraluminal use of the Uniblocker for one-lung ventilation（OLV）in the left side thoracic surgery.Methods:Forty ASA physical status I-III adult patients undergoing elective left side thoracic surgery requiring OLV were enrolled in this study.Exclusion criteria were as follows:age>70 or<18 years;BMI>35kg/m²;ASA classifications>III;modified Mallampati classification≥III;thoracic surgery within the last one month;suspected tuberculosis or systemic infection.All these patients were screened by a senior anesthesiologist preoperatively and randomly allocated to intraluminal use of Uniblocker group（I group,n=20）or extraluminal use of Uniblocker group（E group,n=20）.All the patients in two groups without premedication were received standard monitoring systems in the operating room,including noninvasive arterial blood pressure,heart rate,electrocardiogram,peripheral oxygen saturation.Patients were placed in a supine position and preoxygenated for 3min.For induction,all patients in two groups were intravenously injected with midazolam 0.05mg/kg,fentanyl 3μg/kg,etomidate 0.3mg/kg and vecuronium 0.1mg/kg.All the patients were intubated exactly 2 min after receiving vecuronium by an experienced anesthesiologist.Patients assigned to I group were intubated with the SLT via video laryngoscope until the SLT to appropriate depth and fixed the SLT firmly at the patient’s mouth with cloth tape.The Uniblocker was advanced through the SLT and directed to the left main stem bronchus at a sufficient depth,and then FOB was inserted into the SLT.After further pushing and twisting,the Uniblocker will move into the left mainstem bronchus at optimal position under the visualization of the FOB then inflated the cuff of SLT and fixed the Uniblocker firmly at the end of SLT.Patients assigned to E group were first inserted Uniblocker into the glottis via video laryngoscope.After passing the glottis,the Uniblocker was advanced toward the left main-stem bronchus until slight resistance was encountered,then a SLT with appropriate size was intubated via video laryngoscope into the appropriate depth and fixed the tube firmly at the patient’s mouth with cloth tape then the FOB was inserted into the tracheal tube and guided the Uniblocker to the correct position under direct vision.After this procedure,the cuffs of Uniblocker and SLT were inflated.The cuff of Uniblocker in both groups were inflated with 3 ml to 4 ml of air under direct vision and located appropriately 10-15 mm below the carina in the left main stem bronchus.After the patients were placed in the lateral position,the position of the Uniblocker was reconfirmed by FOB.The primary endpoints were the intubation time（IT）and the correct placement time（PT）.IT and PT were assessed by an independent observer with a stopwatch.The secondary outcomes were the failure of intubation,the incidence of Uniblocker displacement,rank of pulmonary collapse,HR,MAP,Paw,SpO₂ in TLV and 30 minutes after OLV,signs of bronchial injuries and the occurrence of sore throat and hoarseness 24h after surgery.Results:All patients were completed the surgical procedures.There were no significant differences in patients demographics,surgery time and OLV time between two groups（P>0.05）.The time of correct placement of Uniblocker was significantly less in group E（63.4±15.8s）than that in group I（112.6±31.2s）（P<0.05）.The incidence of main bronchial injury was lower in group E（occurred in 2/20）than that in group I（occurred in 5/20）（P>0.05）.The time to intubation,the incidence of Uniblocker displacement,HR,MAP,SpO₂,Paw in TLV and 30min after OLV,the degree of pulmonary collapse and the incidence of sore throat and hoarseness postoperative showed no statistical differences between two groups（P>0.05）.Conclusion:Extraluminal use of the Uniblocker was proved to be a more rapid and more accurate method than conventional intraluminal use of the Uniblocker for OLV in the left side thoracic surgery.Part two A novel method of Uniblocker placement:extraluminal technique supported by trachea length measurementObjective:The objective of this study was to evaluate the accuracy and the feasibility of the distance between the vocal cord and carina measured by chest computerized tomography images as a guide for the placement of Uniblocker.Methods:Seventy adult patients undergoing left side thoracic surgery were included in the study.Exclusion criteria were as follows:age>70 or<18years;ASA classifications>III;BMI>35kg/m²;Modified Mallampati classification≥III;thoracic surgery within one month;severe cardiopulmonary disease.All the patients were randomly allocated to one of two groups:conventional intraluminal intubation group（CV-IN group,n=35）or extraluminal CT guided group（CT-EX group,n=35）.Randomization（1:1）was based on codes generated by computer and these codes were kept in sequentially numbered opaque envelopes until the end of the study.All the patients in both groups were screened by a senior anesthesiologist preoperatively.In the operating room,all the patients were placed in supine position and monitored with HR,NIBP,ECG,SpO₂.For anesthesia induction,all the patients were administered midazolam 0.05mg/kg,fentanyl 3μg/kg,cisatracurium 0.2 mg/kg,and etomidate 0.3mg/kg.All the patients were intubated exactly 3 min after receiving cisatracurium by an experienced anesthesiologist using one of the two intubation methods.In the CV-IN group,the intubation steps were conducted as follows:a single lumen tube（SLT）with appropriate size was inserted into trachea at optimal depth via video laryngoscope and fixing the tube firmly at the patient’s mouth with cloth tape;second,the Uniblocker was lubricated with silicone spray,advanced smoothly through the SLT and directed to the left main-stem bronchus until a very slight resistance was encountered;third,an FOB was inserted into the SLT to assess the position of the Uniblocker and adjust the Uniblocker to an optimal position if the Uniblocker was not in a right position,then inflated the cuff of the SLT and fixed the Uniblocker to the end of SLT.In the CT-EX group,the intubation steps were conducted as follows:the operator counted the number of CT slices（slice thickness is 5mm）from vocal cord slice to carina slice to calculate the distance between vocal cord and carina,then measured this distance（the distance between vocal cord and carina measured by chest CT images plus 10 mm）on the Uniblocker from the upper edge of the cuff towards the proximal end of the blocker and marked it;second,the Uniblocker was lubricated with silicone spray and inserted into the trachea via video laryngoscope.After passing the glottis,the Uniblocker was advanced toward the left main-stem bronchus,once the anesthesiologist saw the marker on the Uniblocker just above the vocal cord,then stopped the insertion and the insertion depth of Uniblocker at the upper incisors was also recorded with a tape mark on the Uniblocker;third,a SLT with appropriate size was intubated via video laryngoscope into the appropriate depth and fixing the tube firmly at the patient’s mouth with cloth tape;forth,the FOB was inserted into SLT to assess the position of the Uniblocker and adjust the Uniblocker to an optimal position if the Uniblocker were not in a right position,then inflated the cuff of SLT and fixed the Uniblocker and SLT to the patient’s mouth separately with cloth tape.The primary outcome parameters of the study were the number of optimal positions of Uniblockers and the injuries of bronchi and carina assessed via FOB after intubation.The secondary outcome parameters were the attempts to adjust the Uniblockers to optimum position,the intubation time（IT）of Uniblockers,the failure of intubations,the adequacy of lung collapse,the incidence of Uniblockers displacement and the occurrences of sore throat and hoarseness 24h after surgery.Results:All the patients were successful for the intubation and no significant differences in patients’sex,age,height,weight,BMI,ASA physical status grade,distance between vocal cord and carina,OLV time and surgery time between the two groups（P>0.05）.In the CV-IN group,19 of 35Uniblockers went to the left main-stem bronchus on the initial blind insertion and 15 of 35 Uniblockers were considered as in optimal depth,whereas in the CT-EX group,32 of 35 Uniblockers went to the left main-stem bronchus on the initial blind insertion and 31 of 35 Uniblockers were considered as in optimal depth（P<0.01）.In the CV-IN group,12 of 35 Uniblockers were successful repositioned via FOB on the first attempt and 8 of 35 Uniblockers needed to be repositioned by more attempts,whereas 4 of 35 Uniblockers were successful repositioned via FOB on the first attempt in the CT-EX group（P=0.26）.The time to Uniblockers intubation was 145.4s in the CV-IN group and 85.4s in the CT-EX group（P<0.01）.The incidence of bronchi and carina injuries was obviously lower in the CT-EX group（occurred in 1 of 35 cases）than that in the CV-IN group（occurred in 8 of 35 cases）（P=0.03）.The malpositions of the Uniblockers were not significantly different between the two groups（P>0.05）.The degree of pulmonary collapse and the adverse events postoperative were not significantly different between the two groups（P>0.05）.Conclusion:The distance between the vocal cord and carina measured according to chest CT images was helpful in predicting the optimal insertion depth of extraluminal use of Uniblocker.Part three The efficacy and adverse effects of the Uniblocker and left side double-lumen tube for one-lung ventilation under the guidance of chest computerized tomographyObjective:One-lung ventilation（OLV）is essential in numerous clinical procedures,in which the left sided double-lumen tube（LDLT）is the most commonly used device.The application of bronchial blockers have been increased in the used of OLV.The present study aimed to compare the efficacy and adverse effects of the Uniblocker and the LDLT for OLV under the guidance of chest computerized tomography（CT）.Methods:A total of 60 adult patients undergoing elective left side thoracic surgery requiring OLV were included in the study.Exclusion criteria were as follows:age>70 or<18 years;BMI>35kg/m²;ASA classifications>III;modified Mallampati classification≥III;thoracic surgery within the last one month;suspected tuberculosis or systemic infection.All patients were randomly assigned to the Uniblocker group（U group,n=30）or LDLT group（D group,n=30）.Randomization（1:1）was based on codes generated by computer and these codes were kept in sequentially numbered opaque envelopes.All the patients in both groups were screened by a senior anesthesiologist preoperatively.In the operating room,all the patients were placed in supine position and monitored with HR,NIBP,ECG,SpO₂.For anesthesia induction,all the patients were administered midazolam 0.05mg/kg,fentanyl 3μg/kg,cisatracurium 0.2mg/kg,and etomidate 0.3mg/kg.All the patients were intubated exactly 3min after receiving cisatracurium by an experienced anesthesiologist using one of the two intubation methods.In the D group,an LDLT of adequate size was used for intubation,which was conducted as follows:The operator measured the distance between the vocal cords and carina according to the CT images of the patient’s chest,on the LDLT from the black line on the endobronchial side of the tube to the side nearest the mouth;a mark was made on the LDLT.Once the cuff of the endobronchial side of the tube had passed the vocal cords,the stylet was removed;the LDLT was rotated 90°toward the left main-stem bronchus and gently inserted further.The operator then identified the mark on the LDLT just above the vocal cords and further insertion was terminated.The correct position of the LDLT was determined by FOB then inflated the cuff of LDLT.In addition,the insertion depth at the upper incisors was recorded and indicated on the LDLT with tape.The LDLT was firmly fixed at the patient’s mouth with cloth tape.In the U group,the Uniblocker was inserted by the same anesthesiologist.The intubation steps were as follows:The operator measured the distance,plus10mm,from the vocal cords to the carina according to the chest CT images at the upper edge of the cuff to the side of the mouth and a mark was made on the Uniblocker.Once the tip of the Uniblocker had passed the glottis,it was inserted further toward the left main-stem bronchus.Insertion was stopped once the operator viewed the marker on the Uniblocker just above the vocal cords.The laryngoscope and Uniblocker were simultaneously held in the right hand of the operator;an SLT of appropriate size was inserted via a video laryngoscope to the appropriate depth and fixed the tube firmly at the patient’s mouth with cloth tape.Then the correct position of the Uniblocker was determined by FOB then inflated the cuff of SLT;the insertion depth at the upper incisors was recorded and a mark was made on the Uniblocker,which was then separately fixed with the SLT at the patient’s mouth with cloth tape.The time for initial tube placement,the number of optimal positions of the tube upon blind insertion,the number of attempts to adjust the tube to the optimal position,the incidences of airway device displacement,the injuries of the bronchi and carina,the duration of lung collapse,the hemodynamic alterations,the End-tidal partial pressure of carbon dioxide(P_ETCO₂),the peak airway pressure（Ppeak）,the plateau airway pressure（Pplat）,the PaO₂,the alveolar-arterial oxygen tension difference（PA-aDO₂）,the intrapulmonary shunt fraction（Qs/Qt）and the occurrence of sore throat and hoarseness 24h following surgery were recorded.Results:There were no significant differences between the two groups in patients’demographics,including age,sex,weight,height,BMI,ASA grade,surgery time,OLV time and the type of thoracic surgery（P>0.05）.The time for successful placement of the LDLT was 83.9±19.4s and that for the Uniblocker was 84.3±17.1s（P>0.05）.The degree of lung collapse 1min following opening of the pleura was greater in group D than that in group U（P<0.01）and the time required for the lung to completely collapse was shorter in the D group（3.3±0.5min）than that in the U group（8.4±1.2 min）（P<0.01）.On the contrary,the incidence of bronchi and carina injuries was lower in the U group（2/30 cases）than that in the D group（10/30 cases）（P=0.02）;the incidence of sore throat was also lower in the U group（2/30 cases）compared with the D group（9/30 cases）.The MAP of patients immediately following the intubation was lower in the U group（122.0±13.4mmHg）than that in the the D group（129.2±12.1 mmHg）（P<0.05）.During OLV,the Ppeak and Pplat in two group were higher compared with two lung ventilation（TLV）（P>0.05）.The Ppeak and Pplat were lower in the U group than that in the D group during OLV_5min,OLV_30min and before OLV_endnd and the P_ETCO₂ was no significantly different between the two groups.During OLV,the PaO₂were lower and the PA-aDO₂,Qs/Qt were higher compared with TLV（P<0.05）,whereas,there were no significant differences between the two groups in PaO₂,PA-aDO₂ and Qs/Qt during OLV and TLV（P>0.05）.Conclusion:The results of the present study indicated that the extraluminal use of the Uniblocker under the guidance of chest CT is an efficient method with few adverse effects in left side thoracic surgery.