Bilateral tension pneumothorax during endoscopic submucosal dissection under general anesthesia diagnosed by point-of-care ultrasound - A case report

Unexpected Tension Pneumothorax Developed during Anesthetic Induction Aggravated by Positive Pressure Ventilation: A Case Report

Background and Objectives: Tension pneumothorax is a life-threatening emergency condition that requires immediate diagnosis and intervention. However, due to the non-specific symptoms and the rarity of its occurrence during surgery, anesthesiologists encounter difficulties in promptly diagnosing tension pneumothorax when it arises intraoperatively. Diagnosing tension pneumothorax can become even more challenging in unexpected situations in patients with normal preoperative evaluation for general anesthesia. Materials and Methods, Results: We report the case of a 66-year-old woman who underwent general anesthesia for oblique lateral interbody fusion surgery of her lumbar spine. Though she did not have any respiratory symptoms prior to the induction of anesthesia, auscultation following endotracheal intubation indicated decreased breathing sound in the left hemithorax of the chest. Subsequently, her vital signs showed tachycardia, hypotension, and hypoxemia, and the ventilator indicated a gradual increase in the airway pressure. We verified the proper depth of the endotracheal tube to exclude one-lung ventilation, and, in the meantime, learned that there had been unsuccessful attempts at left subclavian venous catheterization by the surgical department on the previous day. Tension pneumothorax was diagnosed through portable chest radiography in the operating room, and needle thoracostomy and chest tube insertion were performed immediately, which in turn stabilized her vital signs and airway pressure. The surgery was uneventful, and the chest tube was removed one week later after evaluation by the cardiothoracic department. The patient was discharged from hospital on postoperative day 14 without known complications. Conclusions: Anesthesiologists should be aware of the conditions and risk factors that may cause tension pneumothorax and remain vigilant for signs of its development throughout surgery, even for patients who show normal preoperative assessments. An undetected small pneumothorax without any symptoms can progress to tension pneumothorax through positive pressure ventilation during general anesthesia, posing a life-threatening situation. If a tension pneumothorax is highly suspected through clinical assessments, its prompt differentiation and timely diagnosis are crucial, allowing for rapid intervention to stabilize vital signs.

Translation from manual to automatic endoscopic insufflation enhanced by a pressure limiter

BACKGROUND

Optimal visualization and safety have always been essential in performing any type of endoscopic surgery. However, the safety of automatic gastrointestinal (GI) insufflation has yet to be thoroughly studied, especially when combined with manual insufflation. The current study aimed to verify whether the pressure limiter could lower GI endoluminal pressure during endoscopic procedures and affect the behavioral patterns of endoscopists.

METHODS

A preclinical blinded trial was conducted on endoscopists who had no knowledge regarding the presence of the pressure limiter that prevents a GI endoluminal pressure above 25 mmHg. Endoscopists in group A performed esophageal endoscopic submucosal dissection (ESD) with our insufflation device equipped with the pressure limiter, whereas those in group B performed the same procedure without the pressure limiter. During all procedures, endoluminal pressure was continuously monitored. The primary endpoint of the current study was to measure the endoluminal pressure with or without the pressure limiter during esophageal ESD, while the secondary endpoint was to evaluate the effect of the pressure limiter on intraesophageal pressure and perioperative outcomes during esophageal ESD. A questionnaire survey was conducted after each session.

RESULTS

A total of 79 endoscopists were included in this randomized control study. Group A had significantly lower endoluminal pressure than group B (10.6 ± 4.61 vs. 16.25 ± 7.51 mmHg, respectively; p < 0.05). Although two pigs in group B died from tension pneumothorax, none in group A died. Evaluation of lumen expansion, ease of aspiration, and visual field reproducibility were poorer in group A than in group B, although all fell within the acceptable range. Subjective evaluation of usability was divided into two categories, Excellent/Good and Poor/Bad, with no significant differences in any of the items.

CONCLUSIONS

This preclinical study showed that endoscopic treatment with an automatic insufflation system could be performed at lower endoluminal pressure with a pressure limiter, which had no adverse effects on the endoscopist's feels on endoscopic procedures with the device.