Non-intubated anesthesia in thoracic surgery-technical issues

Ultrasound-guided interventions for controlling the thoracic spine and chest wall pain: a narrative review

Ultrasound-guided injection is useful for managing thoracic spine and chest wall pain. With ultrasound, pain physicians perform the injection with real-time viewing of major structures, such as the pleura, vasculature, and nerves. Therefore, the ultrasound-guided injection procedure not only prevents procedure-related adverse events but also increases the accuracy of the procedure. Here, ultrasound-guided interventions that could be applied for thoracic spine and chest wall pain were described. We presented ultrasound-guided thoracic facet joint and costotransverse joint injections and thoracic paravertebral, intercostal nerve, erector spinae plane, and pectoralis and serratus plane blocks. The indication, anatomy, Sonoanatomy, and technique for each procedure were also described. We believe that our article is helpful for clinicians to conduct ultrasound-guided injections for controlling thoracic spine and chest wall pain precisely and safely.

Non-intubated Thoracic Surgery: Wedge Resections for Peripheral Pulmonary Nodules

The feasibility of performing pulmonary resections of peripheral lung nodules has been one of the main objectives of non-intubated thoracic surgery. The aim was to obtain histological characterization and extend a radical intended treatment to oncological patients unfit for general anesthesia or anatomic pulmonary resections. There is mounting evidence for the role of wedge resection in early-stage lung cancer treatment, especially for frail patients unfit for general anesthesia and anatomic resections with nodules, demonstrating a non-aggressive biological behavior. General anesthesia with single lung ventilation has been associated with a higher risk of ventilator-induced barotrauma and volotrauma as well as atelectasis in both the dependent and non-dependent lungs. Nonetheless, general anesthesia has been shown to impair the host immune system, eventually favoring both tumoral relapses and post-operative complications. Thus, non-intubated wedge resection seems to definitely balance tolerability with oncological radicality in highly selected patients. Nonetheless, differently from other non-surgical techniques, non-intubated wedge resection allows for histological characterization and possible oncological targeted treatment. For these reasons, non-intubated wedge resection is a fundamental skill in the core training of a thoracic surgeon. Main indications, surgical tips, and post-operative management strategies are hereafter presented. Non-intubated wedge resection is one of the new frontiers in minimal invasive management of patients with lung cancer and may become a standard in the armamentarium of a thoracic surgeon. Appropriate patient selection and VATS expertise are crucial to obtaining good results.

Pathophysiological Advantages of Spontaneous Ventilation

Surgical procedures cause stress, which can induce an inflammatory response and reduce immune function. Following video-assisted thoracoscopic surgery (VATS), non-intubated thoracic surgery (NITS) was developed to further reduce surgical stress in thoracic surgical procedures. This article reviews the pathophysiology of the NITS procedure and its potential for reducing the negative effects of mechanical one-lung ventilation (mOLV). In NITS with spontaneous ventilation, the negative side effects of mOLV are prevented or reduced, including volutrauma, biotrauma, systemic inflammatory immune responses, and compensatory anti-inflammatory immune responses. The pro-inflammatory and anti-inflammatory cytokines released from accumulated macrophages and neutrophils result in injury to the alveoli during mOLV. The inflammatory response is lower in NITS than in relaxed-surgery cases, causing a less-negative effect on immune function. The increase in leukocyte number and decrease in lymphocyte number are more moderate in NITS than in relaxed-surgery cases. The ventilation/perfusion match is better in spontaneous one-lung ventilation than in mOLV, resulting in better oxygenation and cardiac output. The direct effect of relaxant drugs on the acetylcholine receptors of macrophages can cause cytokine release, which is lower in NITS. The locoregional anesthesia in NITS is associated with a reduced cytokine release, contributing to a more physiological postoperative immune function.

Non-intubated Thoracoscopic Surgery-Pros and Cons

Pulmonary resection by video-assisted thoracoscopic surgery with single-lung ventilation has become a standardized modality over the last decades. With the aim to reduce surgical stress during operation procedures, some have adopted a uniportal approach in pulmonary resection as an alternative to multiportal VATS. The ERAS program has been widely spread to achieve even better outcomes. In 2004, Pompeo reported the resection of pulmonary modules by conventional VATS under intravenous anesthesia without endotracheal intubation. Within less than a decade thereafter, complete VATS pulmonary resections under anesthesia without endotracheal intubation had been reported for a range of thoracoscopic procedures. Avoiding tracheal intubation under general anesthesia can reduce the incidence of complications such as intubation-related airway trauma, residual neuromuscular blockade, ventilation-induced lung injury, impaired cardiac performance, and postoperative nausea. Numerous studies can be found especially from Asian countries, focusing on comparison of intubated and non-intubated procedures showing that non-intubated VATS could reduce the rate of postoperative complications, shorten hospital stay and decrease the perioperative mortality rate, indicating that non-intubated VATS is a safe, effective and feasible technique for thoracic disease. However, if we look closely at all studies, it is obvious that there are no significant differences between intubated and non-intubated surgery in terms of the standard procedures and maneuvers. In non-intubated procedures it can be less comfortable for the surgeon to manipulate in the thoracic cavity, but the procedural steps remain the same. All the differences between the intubated and non-intubated operation procedure are found in perioperative management of the patient. The patient is still in deep anesthesia during the procedure and hypecapnia can occur. It is easier to manage this if the patient is intubated. In addition, if a complication occurs during the operation and intubation is required, this can cause an emergent situation, which means that not all patients are suitable for such a procedure, especially those with severe emphysema, obese patients and those with a problematic oropharyngeal configuration-Mallampati score. Moreover, studies on non-intubated thoracic surgery point to shortened hospitalization, faster recovery etc. But there are also studies on intubated uniportal VATS procedures in combination with ERAS protocol showing shortened hospitalization and better outcome for patients. Currently, especially with the use of optical intubation canylas, totally intravenous anesthesia (TIVA), BIS and relaxometer, anesthesia is safe for avoiding airway injury, hypercapnia, and there is minimal risk of residual curarization as well as one of the postoperative lung complications such as microaspiration and atelectasis. In addition, the patient recovers rapidly from anesthesia and can be verticalised and mobilized a couple of hours after the operation. It is desirable to take into consideration what type of patient and what lung disease is suitable for non-intubated technique and what is more convenient for intubation.

The comparison of ultrasound-guided thoracic paravertebral blockade and internal intercostal nerve block for non-intubated video-assisted thoracic surgery

Background

To compare the safety and feasibility of ultrasound-guided thoracic paravertebral blockade (TPVB) and internal intercostal nerve block (IINB) for non-intubated video-assisted thoracic surgery (NIVATS).

Methods

Thirty-four patients who underwent NIVATS from April 2016 to May 2017 were retrospectively reviewed and divided into two groups consecutively according to local analgesia treatment, of which 20 patients received TPVB (P group) and the remaining 14 received IINB (I group). A Propensity Score Matching (PSM) analysis was performed to control the selection bias due to nonrandom assignment.

Results

The procedure of propensity scores yielded 2 matched cohorts of 14 patients. There were no significant differences between the two groups regarding gender, age, BMI, and surgical types (P>0.05). Blood-gas analysis 15 minutes after opening the chest showed significantly lower PaCO2 in the P group compared to the I group (P=0.004). The consumption of propofol from anesthesia induction to 15 minutes after opening the chest was also lower in the P group compared with the I group (P=0.012). There were no significant differences in the duration of surgery and visual analogue scale (VAS) pain scores between the two groups (P>0.05).

Conclusions

Ultrasound-guided TPVB can provide safe and reliable local anesthesia for NIVATS.

Ultrasound-guided continuous serratus anterior plane block: dexmedetomidine as an adjunctive analgesic with levobupivacaine for post-thoracotomy pain. A prospective randomized controlled study

Purpose: The study aimed to evaluate the analgesic efficiency of dexmedetomidine (DEX) when added to levobupivacaine in continuous ultrasound-guided serratus anterior plane block (SAPB) performed at the end of major thoracic surgery.

Methods: This randomized, double-blind trial included 50 adults undergoing thoracic surgery. Continuous SAPB was performed at the end of surgery. Patients were randomized into two groups. Group L (n=25) received levobupivacaine only while Group DL (n=25) received a mixture of levobupivacaine and DEX. All patients received intravenous (IV) paracetamol every 8 hrs. Morphine IV was given according to VAS score of pain as a 5 mg loading dose. The primary outcome measure was postoperative pain intensity. Secondary outcome measures were postoperative morphine consumption and adverse effects.

Results: Analgesia was satisfactory in the two groups up to 24 hrs. VAS score was significantly lower in group DL compared to group L between 6 and 24 hrs postoperatively. Total morphine consumption was significantly lower in group DL compared to group L (p<0.001). Up to 12 hrs postoperatively, sedation score was significantly lower in group DL compared to group L. Afterwards, all patients were fully alert. All values of mean arterial pressure and heart rate were within the clinically accepted ranges. There were no recorded cases of hypotension or bradycardia in the whole studied group.

Conclusions: Continuous SAPB with levobupivacaine plus DEX seems to be a promising analgesic alternative following thoracotomy. Combined with IV paracetamol, this approach provided adequate analgesia and proper sedation.

Trial registration: ISRCTN registry; study ID: ISRCTN35517318

Minimally invasive thoracic surgery: beyond surgical access

Thoracic surgery has evolved throughout the decades. The difficulty of accessing the intrathoracic organs through the bony rib-cage has been a challenge for thoracic surgeons. In the past, large incisions stretching across the chest, such as posterolateral thoracotomies with rib spreading was the standard approach to access the lungs. These methods cause large amounts of trauma to the patient, with high rates of mortality and morbidity. However, with the advances in technology and the improvements in surgical technique, thoracic surgery has progressed to minimise trauma to the patient while still maintaining oncological and surgical principles. State-of-the-art technology, combined with wide variety of old and new surgical techniques give the thoracic surgeon a formidable armamentarium. Although there has been a focus on reducing the number and size of surgical wounds, considerations other than surgical approach can reduce the trauma suffered by the patient. Preservation of pulmonary function via organ preservation and anaesthetic techniques to further minimise the systemic inflammation such as non-intubated anaesthesia have also been shown to improve patient outcomes. This article aims to review the recent advances in minimally invasive thoracic surgery.

Non-intubated anaesthetic technique in open bilobectomy in a patient with severely impaired lung function

General anaesthesia has been the most commonly used method for almost all types of thoracic surgery. Recently, there has been a growing interest in non-intubated anaesthetic techniques. The rationale being, to prevent complications related to general anaesthesia and positive pressure ventilation such as barotrauma or ventilation-perfusion mismatch. We present a case with severely impaired forced expiration volume (26%), carbon monoxide diffusing capacity (26%) and VO₂max (13.9 mL/kg/min). According to current guidelines, this patient was suitable to undergo one-lung ventilation only with high risk of morbidity and mortality. Therefore, we chose the non-intubated technique for thoracotomy. Oxygenation was satisfactory throughout, the patient remained hemodynamically stable and the operation was uneventful. Oxygen supplementation was stopped from day 2 and he was discharged on day 7. To our knowledge, this is the first case report where a planned non-intubated method was applied for thoracotomy, and our results suggest that it might be a feasible and safe approach for open thoracotomy in difficult cases where severely impaired lung function indicates that one lung ventilation may carry significant risks.

The non-intubated anesthesia for airway surgery

Surgical treatment for lung cancer including airway resection following reconstruction is typically performed under general anesthesia with single-lung ventilation because it is necessary to maintain a sufficient working space and to adjust the airway pressure for the leak test. However, non-intubated thoracic surgery has been gradually developed in recent years for thoracoscopic surgery, due to its lower rate of postoperative complications, shorter hospitalization duration, and lower invasiveness than the usual single-lung anesthesia. Initially, only minor thoracoscopic surgery, including wedge resection for pneumothorax and the diagnosis of solitary pulmonary nodules, was performed under waking anesthesia. However, major thoracoscopic surgery, including segmentectomy and lobectomy, has also been performed under these conditions in some institutions due to its advantages with respect to the postoperative recovery and in-operating room time. In addition, non-intubated thoracic surgery has been performed for tracheal resection followed by reconstruction to fully explore the advantages of this surgical modality. In this article, the merits and demerits of non-intubated thoracoscopic surgery and the postoperative complications, perioperative problems and optimum selection criteria for patients for thoracic surgery (mainly airway surgery) are discussed.

Non-intubated simultaneous en bloc resection of pulmonary nodule and rib chondrosarcoma

Adequate surgical resection was required for patients with rib chondrosarcoma. A 61-year-old woman was presented with a palpable chest wall mass. Computed tomography (CT) of the chest revealed an isolated pulmonary nodule about 0.9 cm, and a giant rib tumor about 12 cm × 9 cm which penetrated through the 7^th rib into thorax. CT reconstruction and simulated surgery was utilized for disease-free surgical margin (R0 resection), then a simultaneous en bloc resection of pulmonary nodule and rib tumor was performed along with chest wall reconstruction under local anesthesia and intravenous sedation without endotracheal intubation. And the recovery was encouragingly uneventful.

Non-intubated combined with video-assisted thoracoscopic in carinal reconstruction

Carinal reconstruction is a difficult technique combined with video-assisted thoracoscopic surgery (VATS). It has a high requirement on the operator's skills in operating thoracoscope and meanwhile requires the close cooperation from anesthesiologists. Tracheal intubation and ventilator-assisted ventilation are key steps to ensure the success of surgery. However, tracheal intubation itself may influence the exposure of surgical field and increase the difficulty of anastomosis. In close cooperation of anesthesiologists, we did not perform tracheal intubation; rather, we carried out non-intubated complete VATS carinal reconstruction in a patient with adenoid cystic carcinoma (ACC) of the lower trachea. The awake complete VATS carinal reconstruction was successfully performed. The anastomosis lasted about 36 hours, and the whole surgical procedure lasted 230 min. The intraoperative blood loss was about 80 mL. The patient recovered well 100 min after surgery. A semi-solid diet began 6 hours following the surgery. This non-intubated anesthesia method makes the surgery easier, especially during the anastomosis of stumps. It is feasible and safe to apply this anesthesia technique in carinal reconstruction.