Category: New technologies

After attending multiple recent thoracic surgery conferences, where the topic of nonintubated thoracic surgery sparked murmurs and outspoken criticism, thoracics.org conducted a brief review of the literature to attempt to discern if this criticism and skepticism was warranted.  As part of this review, we reached out to several of the leaders in the field, including Dr. Ming-Hui Hung, a well-respected Taiwanese anesthesiologist and widely acknowledged expert on this topic.

Thoracics.org asked for Dr. Hung’s commentary as well as his response to several specific questions on nonintubated thoracic surgery.  Here is his response in it’s entirety (re-formatted to fit the Question and Answer format posed by our correspondence).

Question:  Would you tell me more about your initial research in this area.   What lessons have you learned (overall) in patient selection for non-intubated thoracic surgery?  What additional tips or advice would you offer interested thoracic surgeons/ members of anesthesia?

As we had discussed in our publications, we are facing more and more aging and frail patients with minor thoracic procedures. As surgical approach evolves toward a minimally invasive thoracoscopic technique, we expect that there would be a need for less invasive anesthetic management (i.e. nonintubated VATS) as well. Traditional intubated one-lung ventilation does offer a safe and quiet surgical environment for surgery; however, we still suffer occasionally to have patients complicated with intubation-related adverse effects, not to mention the consuming procedures for successful one-lung ventilation. Actually, there was a short-stature elderly lady complicated with pneumo-mediastinum because of tracheobronchial laceration after a double-lumen tracheal intubation. We was driven by this case we suffered to find a solution and whereas we developed our nonintubated techniques since 2009. As you noted, now nonintubated VATS is a routine part of our armamentarium for thoracic surgery.

To summarize, there are important steps that we learned from our experiences:

1. Thoracic epidural anesthesia (TEA) vs internal intercostal nerve blocks (INB)

In the beginning, we applied TEA. It does provide satisfying analgesia but it is time-consuming and carries more risks for neurological complications. Once again, we had a nonintubated case coincidentally complicated with acute transverse myelitis after surgery. Although we excluded the epidural procedure per se, to be the direct cause of the regretful complication, we were still bothered by a legal suit against us. Then we learned that internal INB is equally effective as a thoracic epidural catheter. It saves time and risk free to do it as we do it under a direct vision by scope, and no touching on any spinal structures. Now INB is our routine part of nonintubated VATS. TEA is considered for those doing a bilateral VATS. We think this is important because it makes nonintubated VATS more safe and even more less invasive, for which our patients would accept this approach more. We Taiwanese are mostly reluctant to have someone doing anything on our spines, as we usually call them the “dragon bones”, the most important part of our bodies.

2. Intrathoracic vagal block

Since cough reflex is a visceral part of autonomic nerve, which is not blocked by TEA or INB, unpredictable cough reflex during surgery could quietly bothering and even dangerous. We soon learned that we could block the cough reflex via intrathoracic vagal nerves. It really works. It alleviates the tension upon surgeons who working on a spontaneously breathing lung and enable them more manipularity of lung parenchyma and hilar structures. Surgeons are still needed to be as gentle as possible for that excessive traction still can trigger cough reflex from the dependent side where vagal nerve function is intact.

3. Sedation and titration of its depth

We know there is an “awake, or not awake” issue on nonintubated VATS. We prefer to sedate our patients just because our patients do not want to be awake during surgery. Lateral decubitus position is not a confortable position. Most of our patients undergo surgery because of lung cancer or potential lung cancer. It usually takes 1-2 hours to have a diagnosis first and complete the definite treatment upon the final pathological result. We believe no one would like to be anxiously awake for the result with an open chest in an awkward position. In addition, the initial phase of iatrogenic pneumothorax would cause the patient dyspneic and tachypneic for a while, giving patient sedated with supplemental opioid is useful to alleviate the respiratory disturbances and accelerate the operated lung to collapse. By applying bispectral index EEG monitor, we can observe the BIS index increasing during the initial phase of open pneumothorax, it could be caused by inadequate analgesia, or just because of a dyspneic response. We may give the patients some more anesthetic and it usually recovered after effective vagal block. Carefully observe the respiratory pattern (from the video, or using an noninvasive end-tidal capnography) is of importance. Anesthesiologists should keep vigilant on the respiratory pattern and airway patency of the nonintubated patients, including a plan B for intubation conversion.

4. Patient selection

We operate on spontaneous breathing lungs (most of the time, the operated lung collapses well because of positive pressure introduced into the chest cavity). The remaining opposite lung is sufficient to maintain satisfactory oxygen saturation, despite unavoidable hypoventilation. However, a vigorous diaphragm would jeopardize the balance. For surgery, it causes excessive movement of the operated lung and makes hilar manipulation dangerous or even impossible. For respiration, CO₂ rebreathing (an to-and-fro phenomenon between the dependent and the non-dependent lung) would further exacerbate the breathing pattern and decrease the alveolar oxygen fraction of the nondependent lung, leading to oxygenation desaturation. It is the most common scenario of our difficult cases and we changed to intubation conversion in some of them, especially in major resections (i.e. lobectomy) for lung cancer. We learned that obese patients tend to be an abdominal breather because of an elevated diaphragm and they are usually associated with excessive diaphragmatic movement during nonintubated surgery. Other contraindications for nonintubated VATS are also listed on the literature. We suggest that are mostly at the discretions of the caring surgeon and anesthesiologist as their good clinical practice routines.

Question:  How have your findings of your work been received internationally?  At several recent conferences, there has been a lukewarm or even critical response towards nonintubated thoracic surgery.  Is this a frequent response? 

A typical unfriendly tone from other colleagues is “just because it can be done, should it be done?” We have the same feelings as you experienced in those meeting. Nonetheless, our findings are relevant and robust that nonintubated VATS is feasible and safe in selected patients with a variety of thoracic procedures. They were published in well-known surgical journals in cardiothoracic field, including Annals of Surgery, Journal of Thoracic and Cardiovascular Surgery, Annals of Thoracic Surgery and the European Journal of Cardio-Thoracic Surgery. Still, there are surgeons and anesthesiologists enthusiastic about less invasive alternative for their caring patients visiting our hospital for nonintubated VATS, including Korea, China, Switzerland internationally and other hospitals nationally.

We believe it is human nature being anxious and doubtful to do something you do not get familiar with, especially when intubated one-lung ventilation is nearly an unbreakable only golden standard for thoracic surgery for decades, and almost all thoracic surgeons in current generations would request a fully collapsed lung to operate upon. But at this time, we are approaching a 1000 nonintubated VATS case volume, and all thoracic anesthesiologists and thoracic surgeons in our hospital are dealing with nonintubated VATS if this is appropriate for their patients. We think it is quiet a milestone in our program.

Five years ago, I asked one of my colleagues, a nursing anesthetist [emphasis mine] whether she would choose nonintubated technique if she needs a VATS procedure.

She said, “Well, I need to think about it. You better give me an double lumen even though I know how big it is.”

One year later, her answer to the same question is a “Yes, please, no tube.”

Question: Are there any other obstacles for researchers in this area?  Do you have other on-going research programs at your facility?

Obviously, nonintubated patients recover from surgery fast. They can shift to the gurney on their own from the surgical table. They experience less pain and less PONV in PACU, which enables them to recover oral intake sooner with oral analgesics and early ambulation, not to mention those common adverse effects after double lumen intubations, such as a sore throat and a change of voice quality. Currently, we are drafting our manuscripts about nonintubated VATS pulmonary resection in patients with compromised lung function. Meanwhile, a randomized trial is under investigation to compare the recovery differences of nonintubated VATS vs. intubated VATS.   There are also several more nonintubated trials in Clinicaltrial.org in different countries.

Question: Do you know of any programs that have adopted your techniques and protocols?

To our knowledge, Dr. Jianxing He from the First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China, is also an enthusiastic advocator and pioneer in nonintubated VATS. He is also leading journals such as Journal of Thoracic Disease andAnnals of Translational Medicine as an open forum to accelerate the impact of nonintubated VATS. He is going to publish a state-of-the-art monograph dedicated to nonintubated VATS in the near future. We believe you can get useful information regarding nonintubated VATS in China and different perspectives from him.

As always, we keep doing our best to satisfy our patients’ need during their curing and recovery processes, just because “our patients, first.”

Ming-Hui Hung, MD, MS

Anesthesiologist, Department of Anesthesiology

Jin-Shing Chen, MD, PhD

Professor, Department of Surgery

National Taiwan University Hospital

Thoracics.org would like to thank Dr. Hung and his colleagues for their continued work in this area.  Thoracics.org would also like to thank Dr. Hung for his willingness and frank candor in addressing some of the other issues in this area.

Additional References and Resources

Ke-Cheng Chen^1,3, Ya-Jung Cheng², Ming-Hui Hung², Yu-Ding Tseng³, Jin-Shing Chen (2012).  Nonintubated thoracoscopic lung resection: a 3-year experience with 285 cases in a single institution.  Journal of Thoracic Disease, Aug 2012, 4(4).

Hung MH, Hsu HH, Cheng YJ, Chen JS. (2014).  Nonintubated thoracoscopic surgery: state of the art and future directions. J Thorac Dis. 2014 Jan;6(1):2-9. doi: 10.3978/j.issn.2072-1439.2014.01.16. Review. (Best read in pdf form).

Liu YJ, Hung MH, Hsu HH, Chen JS, Cheng YJ. (2015).  Effects on respiration of nonintubated anesthesia in thoracoscopic surgery under spontaneous ventilation.  Ann Transl Med. 2015 May;3(8):107. doi: 10.3978/j.issn.2305-5839.2015.04.15. Review

Fast track thoracic surgery: nonintubated minimally invasive surgery for complex procedures.  October 4, 2015.

Readers: Thoracics.org has highlighted a key phrase in Dr. Hung’s response that also, unintentionally but directly addresses one of the criticisms recently advanced by a noted American thoracic surgeon who challenged Dr. Martinez as to whether he would ever delegate the care of a nonintubated patient to a nurse anesthetist.  When Dr. Martinez hesitated in his response, the surgeon claimed victory, stating, “See?  That would never work in American hospitals, [where certified nurse anesthetists oversee the majority of cases]”.  This was his rationale for dismissing this technique, even when it might make otherwise inoperable patients eligible for life-saving surgery.  That dismissal of both his American colleagues and the needs of the more fragile subset of our thoracic surgery population demonstrates some of the limitations in our so-called “masters” or “giants” of thoracic surgery.  While great, and influential surgeons, they are not infallible.  Their experiences carry wisdom, but their opinions shouldn’t carry more weight than any other published study.

Thoracics.org is committed to giving a voice and forum to all specialties and members of the thoracic surgery community.