Can An Embolectomy Catheter Become a One Stop Solution for Lung Isolation in One Lung Ventilation?

One Lung Ventilation (OLV) is often required for surgeries in the thorax; patients may belong to any age group. If the patients are adult, the options for lung isolation are many, but handicap arises when one is dealing with paediatric patients. While dealing with pediatric patients, Embolectomy Catheters (EC) may be quite useful as they are available in a wide range of sizes, making them appropriate for lung isolation even in neonates. Besides, ECs can be improvised to achieve selective lobar separation in patients who have borderline lung function and are at risk for intraoperative hypoxemia. Though EC is a versatile device, it is underutilized; only a few low-quality pieces of evidence are available. Among the people who have used ECs for lung isolation, the technique of insertion had been variable. This article is an attempt to review the methods of lung isolation and explore the possibility of EC becoming a universal device for lung isolation. Background One Lung Ventilation (OLV) is usually indicated in thoracic, oesophageal, vascular and nonthoracic surgical settings in perioperative period. A variety of surgeries require OLV; an indication can be to improve the exposure of intrathoracic structures or to prevent soiling of the healthy lung with contaminant from the affected lung. Now a days, Embolectomy Catheters (ECs) are becoming more popular for One Lung Ventilation (OLV) because of their easy availability even in resource limited health care facilities. The purpose of this review is to provide an update on emerging evidence and defining the role of ECs in OLV, both in paediatric and adult patients. Challenges of OLV in paediatric patients and available lung isolation techniques OLV in paediatric patients is a challenge to all anaesthesiologists; smaller the airway, greater is the challenge. Antero-Posterior (AP) diameter of a neonatal trachea, in both males and females is just 4.3mm; at 15 years, the size increases to 14mm in both sexes, thereafter the trachea in female stops growing, while in males it grows to a size of 16-18mm at 19years (Table 1). In adults, the Lung Isolation Techniques (LITs) most commonly used are Double Lumen Tubes (DLTs); less common options include, Bronchial Blockers (BB), Univent Tubes (UT), and Embolectomy Catheters (EC). Double lumen tube: DLT is most popular, but it is not available below 26 Fr [1]. A generic interpretation of a 26Fr DLT is two 4mm ETTs joined together, implying thereby that in order to accommodate even the smallest DLT the tracheal diameter has to be more than 8mm and the bronchial diameter has to be more than 4mm. So, a DLT is fit for paediatric patients of age more than 8 years, weighing more than 30kg or height more than 130 centimeters; recommended size varies with age and human race too [2]. According to Brodsky, appropriate size of DLT may be determined either by direct Research Article Can An Embolectomy Catheter Become a One Stop Solution for Lung Isolation in One Lung Ventilation? Jain A* Department of Anesthesiology, Gandhi Medical College, Bhopal, Madhya Pradesh, India *Corresponding author: Anuj Jain, Department of Anesthesiology, Gandhi Medical College, Bhopal, Madhya Pradesh, India Received: July 03, 2020; Accepted: August 13, 2020; Published: August 20, 2020 measurement of bronchial diameter in a chest radiograph or by predicting left Bronchus Diameter (BD) based on Tracheal Diameter (TD) according to the formula, LBD=(0.4×TD)+ 3.3 [3]. Marraro-bilumen tube: These bilumen tubes can be used in smaller paediatric patients; smallest tube is made of two 2.0 mm tubes molded together. The sizes may go up to two 3-3.5mm tubes molded together, making it appropriate for 2-3 years age group. Although Marraro tubes may be used in neonates, it is usually unavailable and most anaesthesiologists are unaware that such tubes even exist. Univent Tube (UT): A UT with an Internal Diameter (ID) of 3.5mm has an External Diameter (ED) of 7.5-8.0mm, while the one with 4.5mm ID have an ED of 8.5-9.0mm. The large ED limits its use in Asian paediatric population smaller than 4-6years of age [4]. Bronchial blockers: Arndt’s BB are available in 5,7 and 9Fr and are appropriate for 6month to 6 years, 6 years to 14 years and 14-18 years age groups respectively [5]. BBs have a low pressure cuff and a coaxial channel for suctioning, which allows active deflation of lung. Apart from its high cost and less availability, the major disadvantage of BBs is that the loop guide wire (which is essential for placement) once removed cannot be reinserted, rendering it useless if need for repositioning arises. In a RCT by Narayanaswamy, the misplacement rate of Arndt’s blocker (the most popular among the 3 BBs) was higher compared to other two BBs [6]. Endobronchial Single Lumen Tube (SLT): SLTs can be used for lung isolation in emergency situations like contralateral pneumothorax [7]. Some anaesthesiologists also insert two SLTs, one in trachea and other in the bronchus. Endobronchial SLT has a tendency to progress to the right side due to the more inline orientation of the right bronchus. It can be of concern, if surgery needs to be performed in the right hemithorax. In order to overcome this problem, Chengod et al., [8]. Suggested left endobronchial intubation using a SLT that was curved towards the left side (with a stylet). However, this approach may not be appropriate up to 2 years of age as the diameter of the left