Predicting clinical entry point for thoracic epidural catheter insertion during paramedian approach: A prospective observational study.

Background and Aims: Thoracic epidural insertion has high failure rates in the mid-thoracic region due to steep angulation of oblique bending of spinous processes. The preferred skin puncture point for epidural needle insertion in the paramedian sagittal plane with respect to the superior/inferior tip of spinous process or inter-spinous cleft in the mid-thoracic region (T5-8) is not standard. The primary objective of this prospective observational study was to find the skin puncture point which had the best success rate for a successful epidural catheterization. Secondary objectives were to study the number of attempts and passes required to locate epidural space, incidence of failed epidural, and its relationship with patient characteristics and demographics. Material and Methods: After informed consent, 155 patients planned for general anesthesia with epidural analgesia in the mid-thoracic region were included in the trial. Patient demographics, the details of epidural attempts with respect to anatomical landmarks, distance from the midline, and number of passes in each attempt were noted. Epidural catheterization was considered successful after demonstrating dermatomal band of sensory blockade. Results: The success rate at different skin puncture sites was not statistically significant (P = 0.58). We found a failure rate of 12.9%. Failed epidural catheterization was significantly high in the age group >56 years (n = 62 and P = 0.007). Conclusion: In our study, none of the skin puncture points had a significant association with successful epidural insertion in mid-thoracic segments using a para-median approach.

A single-arm prospective interventional study to assess the efficacy of continuous bronchial cuff pressure monitoring to detect the displacement of lung isolation devices in elective thoracic surgeries.

Background and Aims: During proximal or distal migration of lung isolation device (LID), the bronchial cuff would move into a wider or narrower portion of the bronchus, leading to a decrease or increase in the cuff pressure, respectively. To test this hypothesis, we conducted a study to find out the efficacy of continuous bronchial cuff pressure (BCP) monitoring for detecting the displacement of LID. Methods: A single-arm interventional study was conducted including hundred adult patients undergoing elective thoracic surgeries using a left-sided LID. BCP was monitored in a continuous manner using a pressure transducer connected to the bronchial cuff of the LID. The position of the LID was assessed using a paediatric bronchoscope. Changes in the BCP were noted when the LID was moved intentionally in the left main bronchus (part 1) and during the surgery (part 2). Bronchoscopic confirmation was performed at the end of the surgery to note any uncaptured movement of the LID (part 3). Results: During part 1 of the study, BCP consistently decreased on the proximal movement and increased on the distal movement of the LID, although the magnitude of change was not constant. During part 2 of the study, sensitivity, specificity, positive predictive value, negative predictive value and accuracy of continuous BCP monitoring to detect the dislodgement of LIDs (n = 41) during the surgery were 97.6%, 40%, 76.9%, 88.9% and 78.7%, respectively. Conclusion: Continuous BCP monitoring is a useful and sensitive method for monitoring the position of left-sided LIDs in limited-resource settings.

The modern integrated anaesthesia workstation.

Over the years, the conventional anaesthesia machine has evolved into an advanced carestation. The new machines use advanced electronics, software and technology to offer extensive capabilities for ventilation, monitoring, inhaled agent delivery, low-flow anaesthesia and closed-loop anaesthesia. They offer integrated monitoring and recording facilities and seamless integration with anaesthesia information systems. It is possible to deliver tidal volumes accurately and eliminate several hazards associated with the low pressure system and oxygen flush. Appropriate use can result in enhanced safety and ergonomy of anaesthetic delivery and monitoring. However, these workstations have brought in a new set of limitations and potential drawbacks. There are differences in technology and operational principles amongst the new workstations. Understand the principles of operation of these workstations and have a thorough knowledge of the operating manual of the individual machines.