Chest infection is a health care problem in many regions of the world, and pleural empyema is the most common type of surgical chest infection. In the past decennium, the introduction of nonintubated surgery and uniportal video-assisted thoracic surgery changed considerably surgical treatment of pleural empyema. Although the advantages seem evident, the need for randomized controlled trials is necessary to confirm the usefulness. Moreover, in the future, an education and training program for thoracic surgeons and anesthesiologists would allow increasing the number of awake surgical options in caring for patients with stages II to III empyema.
Video-assisted thoracic surgery (VATS) is accepted as a useful treatment option for stages II to III pleural empyema.
Uniportal VATS has all the potential to become the standard of care for stages II to III pleural empyema.
Nonintubated VATS is indicated in very ill patients.
Nonintubated anesthesia is easier to perform using uniportal VATS.
Chest infection is a health care problem in many regions of the world; in particular, lower respiratory tract infection is the fourth most common cause of death globally and one of the major causes of postoperative death. Chest infection affects principally the lung, and the main causes include virus and bacteria.
Chest infections can affect people of all ages, including children, the elderly, and smokers. Moreover, people who are already ill (with chronic obstructive pulmonary disease or heart, liver, or renal disease) and older people are most likely of developing a chest infection.
Clinically, patients develop high temperature (fever) above 38Cº; chest pain, which is made worse when breathing; dry cough; chills; excessive sweating, particularly at night; shortness of breath; and general sense of feeling unwell.
Because 10% of patients with pleural effusion due to pneumonia develop loculation or progress to empyema, thoracic surgeons often are involved when more life-threatening complications appear, such as empyema and lung abscesses.
The incidence of pleural empyema has increased since 1990, and it has affected more than 65,000 patients each year in the United States and United Kingdom. From 1996 to 2008, the hospitalization for pleural empyema increased from 3.0 to 5.9 per 100,000 in the United States population. Postpneumonic pleural empyema, the most common form of pleural empyema (60%), is increasing in North America and Europe and is recognized as a major cause of morbidity and prolonged hospital stay. The second most common cause of pleural empyema is postsurgical (30%), for example, pleural empyema caused by postoperative bronchopleural fistula or in pneumonotomies patients. Despite medical treatment, patients suffering with pleural empyema develop significant morbidity and mortality. The American Thoracic Society divides pleural empyema in 3 stages, as in listed Table 1 .
|American Thoracic Society Stage||Type of Empyema|
Diagnosis usually is performed during the first stage and it is based on the results of a thoracocentesis, which shows a purulent fluid, glucose less than 50 mg/dL, high protein greater than 30 mg/dL, pH less than 7.2, and lactate dehydrogenase greater than 1000 IU/L. Treatment is generally nonsurgical.
The fibrinopurulent stage (stage II) has been characterized by a thick fluid and thick fibrin strands ( Fig. 1 ), pH less than7.2, lactate dehydrogenase greater than 1000 IU/L, glucose less than 60 mg/dL, positive culture or presence of suppuration, and increased loculations in the pleural cavity. Fibrinopurulent empyema changes into an organizing stage within 7 days to 10 days of symptom initiation. In addition, lung entrapment should be suspected when the pleural infection process is known to have been ongoing for longer than 10 days to 14 days. The 3 stages of pleural empyema require an individualized treatment, but only the second and third stages are definitely for thoracic surgeons.
A lung abscess is a rare complication of pneumonia and is mostly seen in people who have a serious, preexisting illness or those with a history of severe alcohol misuse. The symptoms of a lung abscess are the same as those of severe pneumonia. In addition, the patients could start to cough up unpleasant-smelling phlegm and experience swelling in fingers and toes. Most cases of lung abscesses can be treated using antibiotics. This usually involves an initial course of intravenous (IV) antibiotics (directly into a vein through a drip) followed by oral antibiotics (tablets) for 4 weeks to 6 weeks. Most people who have a lung abscess experience an improvement in their symptoms within 3 days to 4 days. It is important to finish a recommended course of antibiotics, even if feeling perfectly healthy, to prevent reinfection of the lungs. Approximately 10% of people require invasive treatment because they fail to respond to the antibiotics. Surgery is rare because many patients with lung abscesses are now being drained under guidance of computed tomography (CT) scan without the necessity of removing the affected section of the lung.
Aim of the article
In the past decennium, the broadened use of uniportal video-assisted thoracic surgery (VATS) and nonintubated surgery has changed considerably surgical treatment of pleural empyema. Nonintubated VATS has been reported safe and feasible in many circumstances, such as major lung resection, pneumothorax, wedge resection, and lung volume reduction surgery.
This article has been written with the intention to answer the following 2 questions:
Is nonintubated surgery appropriate for VATS treatment of pleural empyema?
What is the best VATS approach for nonintubated surgery in the treatment of pleural empyema?
Nonintubated anesthesia for pleural empyema
Until the advent of VATS, curative surgery for pleural empyema was mainly performed under general anesthesia with a double-lumen tube. It is evident that anesthetic management for awake surgery in patients with pleural empyema is more challenging than under general anesthesia, requiring experience and careful patient selection. Nonintubated VATS certainly represents a step forward, and it is to be considered suitable for selected patients, with many advantages. In general, the absence of general anesthesia results in early postoperative pulmonary re-expansion, faster recovery, and a decrease in hospitalization. Several techniques have been described to perform an operation without an endotracheal tube in patients with pleural empyema. Buckingham and colleagues described in 1950 experience with of 617 thoracic surgery procedures performed under thoracic epidural anesthesia, and in 1954 Vischnevski reported a series 600 thoracic surgery procedures performed under local anesthesia. Paravertebral block has also been reported to perform nonintubated VATS.
During awake surgery, the iatrogenic pneumothorax allows a sufficient lung collapse, allowing it to work smoothly. Moreover, the presence of spontaneous breathing and mobility of the diaphragm counteract the possibility of a mediastinal shift. The main advantage of nonintubated surgery for empyema is the particular importance in unstable patients with multiple comorbidities or in patients allergic to general anesthesia. Rare reports have demonstrated that VATS decortication could effectively manage empyema in awake patients using epidural or paravertebral nerve block. It was even suggested that spontaneous lung ventilation resulted in easier dissection during the operation, resulting in lower postoperative morbidity.
Patients must be informed of their rights & responsibilities before consenting, and accurate perioperative care is of paramount importance for successful patient management.
After positioning, the patient is continuously monitored for the duration of the surgery, with pulse oximeter, electrocardiogram, invasive blood pressure, bispectral index, and arterial blood gases. Midazolam, 1.5 mg, and fentanyl, 50 μg, also are administered. The objective is to keep the bispectral (BIS) index between 75 and 85. Patients are kept at spontaneous breathing with oxygen saturation as measured by pulse oximetry 95% to 96% (nasal cannula fraction of inspired oxygen 30%). Arterial blood gases are monitored intraoperatively and Acetaminophen (paracetamol), 1 g, is administered as an analgesic. Acetaminophen (paracetamol), 1 g, is administered as an analgesic.
Although several anesthetic techniques have been reported for VATS in pleural empyema, in 1998, the author introduced a 4-step local anesthesia and sedation for thoracic procedures with excellent results in many patients. During surgery the anesthetist continuously monitored noninvasive blood pressure, electrocardiogram, and oxygen saturation. Facial mask was used to administer oxygen, and IV cannula inserted. Premedication was performed with droperidol and atropine before operation. Sedation was maintained by diazepam given a few minutes before local anesthesia, using ropicavaine in 4 different steps.
The first step was the injection of local anesthetic made at the site of the 2 cm above and parallel to the rib and the dissection started though the subcutaneous tissue.
The second step was the injection of local anesthetic at the aponeurosis of the thoracic muscles.
After the muscle is opened, the third step consisted of palpating the rib and make the incision down to the rib.
The fourth and final step consisted of anesthetizing the pleura by infiltration through the intercostal muscles for 3 cm to 4 cm. The incision was then made on the superior border of the rib. Just before the pleural is opened, another IV bolus of propofol was administrated (30–60 mg IV in 10–15 s).
Decreased oxygen desaturation was treated with increasing oxygen flow. When necessary, propofol was injected by demand and plasma expanders were used to treat hypotension secondary to propofol. The instrumentation and the drug for general anesthesia were always available in the operating room.
It is mandatory before surgery to have the correct empyema stage assessment, which must be done with a clear description of the radiographic aspect and with a CT scan, which can help to locate the presence of a thick pleura, which is a pathognomonic sign of stage 3 empyema, as shown in Fig. 2 .