Crisis management during Non-Intubated VATS procedures - by Dr Jose Navarro

During the last years, there has been an increasing interest in Non-Intubated Video-Assisted Thoracic Surgery (NI-VATS). There are obvious advantages, including the the non-instrumentalisation of the infraglotic airway and the deleterious effects of the positive mechanical ventilation. But, as everything in life, it´s not all rosy.

That´s what we are going to talk in this post, about all the problems you can find yourself and how to solve them.

When we decide to start a new technique we can find two types of adoptions: the “early-crazy” adopters, the ones who say: “let´s do it, it's easy”. Usually these type of colleges are very experienced, and they can “control” everything. The real thing is that they are not really conscious of all the complications they can find themselves. All of us, in some time in our life, have been early ones. The other way is the “late-conscious” adopters who analyze all the possibilities and wait for studies that endorse their actions. The majority of us are in the middle of them. We try to do innovating things, for the best for the patient in a safe environment. That´s the key point: patient safety.

The way to do it safe is to: prevent things before they happen and manage the complications in the best way.

Preventives strategies

Always-experienced team perform NIVATS. What do we understand “experienced”? Surgeons, anesthesiologists and OR nurses who have performed more than 50 conventional VATS, overcome the learning curve in conventional multiportal VATS and uniportal VATS (more than 50 major procedures through each approach) and have experience with difficult cases of major lung resections [big and central tumors, broncho-angioplasties, tumors of the apex, tumors with invasion of surrounding structures (diaphragm, chest wall, pericardium)], and management of complications such as moderate to severe bleeding through the VATS or single-port approach. In addition, the anesthesiologist must be trained in the lateral intubation at least in 20 cases (left and right).

In addition, the use of clinical simulation is a very useful tool to train all the team. Human patient simulators (mannequins) are whole-body human simulators designed to provide an accurate anatomic representation of patients. Using patients monitors changes in the physiological and physical variables can be made.

In our environment (operating room) it can be especially useful for the training of non-technical skills.

Prior to the surgery we do the following checklist:

Previous to surgery :

1. Surgical and anesthesiological specific informed consent for NI-VATS

2. WHO surgical safety checklist

3. Remind the patient he can feel dyspnea

4. Two experienced anesthesiologist and two surgeons available

Emergency table :

1. Neutral position of the head and occipital support

2. Guedel canula

3. Macintosh laryngoscope and two blade sizes

4. Double lumen Airtraq® videolaringoscope

5. Two sizes of double-lumen tubes [35-37]

6. Two sizes of single lumen orotracheal tubes (7 and 7.5 internal diameter)

7. Fuji UniblokerÔ endobronchial blocker (7 Fr)

8. Bronchofiberscope ready to use (3.7 mm)

9. Anesthesia induction agents (propofol + fentanyl + rocuronium)

10. Neuromuscular reversal agents (Sugammadex®)

11. Thoracic drainage (24 Fr)

Crisis resource managenment strategies (CRM)

Once complications occurs the best way to manage it is by the application of the CRM elements that Prof Dr. Gaba introduced more than 20 years ago.

Those elements include:

· Knowing the environment and available resources

· Anticipate and plan, call for help early

· Excercise leadership and followership

· Distribute the workload

· Mobilize all available resources

· Communicate effectively

· Use all the available information

· Prevent and manage fixation errors

· Cross (double) check

· Use cognitive aids (www.anestcritic.org)

· Re-evaluate repeatedly

· Use good teamwork

· Allocate attention wisely

· Set priorities dynamically.

All of these can be trained using clinical simulation adapted to the NIVATS (Navarro-Martínez J, Gálvez C, Rivera-Cogollos MJ, et al. Intraoperative crisis resource management during a non-intubated video-assisted thoracoscopic surgery. Ann Transl Med 2015;3:111.)

Before we start to describe the clinical and critical situations we can find ourselves it´s important to know that the anesthetic technique is in a constant evolution. At the beginning we use to do patients sedated with propofol an remifentanil (BIS around 40-50) with an oropharyngeal airway (Guedel o Mayo) but now we started to use a laryngeal mask (LM) maintaining the spontaneous ventilation.

1. Respiratory acidosis: It is very common and well tolerated; specially when the laryngeal mask is used and a small pressure support can be added in case of moderate-severe hypercapnia.

2. Hypoxemia: The degree of hypoxemia depends on the type of patients. We all see in the young patients the PaO2 arterial drop is much higher than the “pathological” lung. That´s way the NIVATS technique it has been used in patients were the conventional surgery has been contraindicated. With or without LM usually its not a big problem

3. Dyspnea: At the beginning of the program when we did awake patients we always had to explain the possibility of suffering for a while of dyspnea. Nowadays due to the deep sedation used this is not an issue.

4. Cough: This is very usual problem that we can find ourselves due to the stimulus via the vagus nerve. Even the predominance of the vagal tone after sympathetic block if an epidural catheter is used can increase it. The best way to try and abolish the cough is intrathoracic vagal block with 2 mL of 0.25% bupivacaine adjacent to the vagus nerve under direct thoracoscopic vision at the level of the azygous vein in the right side, and just below the aortopulmonary window in the left side, in order to avoid laryngeal recurrent nerve palsy

5. Severe bleeding: The big, real, emergency. Depending on if the bleeding can be controlled by VATS or no de management is totally different. If both cases a general anaesthesia and tracheal intubation is undertaken. A nurse (or resident) helps the anaesthesiologist. For that reason in our protocol always a big peripherical venous catheter is inserted (plus the standard one) in the contralateral side of the surgery.

Criteria for a conversion to thoracotomy and/or general anesthesia

• Conversion to General Anesthesia and orotracheal intubation

1. Respiratory acidosis with pH <7.1, with tachypnea (> 30 rpm)

2. Hypoxemia (PaO2 <60 mmHg) without improvement despite high-flow oxygenation or non-invasive ventilation

3. Continuous cough without improvement despite aerosolized lidocaine or vagal block with local anesthetic

4. Anxiety attack without improvement with deeper sedation

5. Voluntary desire of the conversion patient

• Conversion to multiportal VATS

1. Extensive adhesions of the lung to the chest wall

2. Large tumors, especially in the more central and anterior portion of the lung, which make it difficult to manipulate the hilar structures through the single incision

3. Inadequate pulmonary collapse with difficult mobilization

4. Mild bleeding

• Conversion to open thoracotomy

1. Impossibility of palpating the lesion through the single incision in the patient not intubated (small nodules, central location) in case of not having a harpoon for its previous marking.

• Conversion to open thoracotomy and general anesthesia and orotracheal intubation

1. Moderate or severe uncontrollable bleeding through the non-intubated videothoracoscopic approach, which requires more important maneuvers for its control (pulmonary artery clamping, direct repair, reconstruction)

To conclude, remember that if you decide to start a NIVATS program one has to be always in the safe side. Starting with of the strategies of prevention of complications, applyin the crisis resource management guidelines and training all the potential problems that can happened before, during and after the surgery

Jose Navarro-Martinez - Anesthesiology and Surgical Critical Care - Anestcritic