Cardiovascular collapse caused by carbon dioxide insufflation during one-lung anaesthesia for thoracoscopic dorsal sympathectomy

Cardiorespiratory impact of intrathoracic pressure overshoot during artificial carbon dioxide pneumothorax: a randomized controlled study

BACKGROUND

The aim of this study is to evaluate cardiovascular and respiratory effects of intrathoracic pressure overshoot (higher than insufflation pressure) in patients who underwent thoracoscopic esophagectomy procedures with carbon dioxide (CO₂) pneumothorax.

METHODS

This prospective research included 200 patients who were scheduled for esophagectomy from August 2016 to July 2020. The patients were randomly divided into the Stryker insufflator (STR) group and the Storz insufflator (STO) group. We recorded the changes of intrathoracic pressure, peak airway pressure, blood pressure, heart rate and central venous pressure (CVP) during artificial pneumothorax. The differences in blood gas analysis, the administration of vasopressors and the recovery time were compared between the two groups.

RESULTS

We found that during the artificial pneumothorax, intrathoracic pressure overshoot occurred in both the STR group (8.9 mmHg, 38 times per hour) and the STO group (9.8 mmHg, 32 times per hour). The recorded maximum intrathoracic pressures were up to 58 mmHg in the STR group and 51 mmHg in the STO group. The average duration of intrathoracic pressure overshoot was significantly longer in the STR group (5.3 ± 0.86 s) vs. the STO group (1.2 ± 0.31 s, P < 0.01). During intrathoracic pressure overshoot, a greater reduction in systolic blood pressure (SBP) (5.6 mmHg vs. 1.1 mmHg, P < 0.01), a higher elevation in airway peak pressure (4.8 ± 1.17 cmH₂O vs. 0.9 ± 0.41 cmH₂O, P < 0.01), and a larger increase in CVP (8.2 ± 2.86 cmH₂O vs. 4.9 ± 2.35 cmH₂O, P < 0.01) were observed in the STR group than in the STO group. Vasopressors were also applied more frequently in the STR group than in the STO group (68% vs. 43%, P < 0.01). The reduction of SBP caused by thoracic pressure overshoot was significantly correlated with the duration of overshoot (R = 0.76). No obvious correlation was found between the SBP reduction and the maximum pressure overshoot.

CONCLUSIONS

Intrathoracic pressure overshoot can occur during thoracoscopic surgery with artificial CO₂ pneumothorax and may lead to cardiovascular adverse effects which highly depends on the duration of the pressure overshoot.

TRIAL REGISTRATION

Clinicaltrials.gov ( NCT02330536 ; December 24, 2014).

Is two lung ventilation with artificial pneumothorax a better choice than one lung ventilation in minimally invasive esophagectomy?

Two lung ventilation (TLV) with artificial pneumothorax has been introduced into MIE for several years. A few researches have reported its clinical application, and proved its safety and feasibility. However, it is still controversial whether TLV with artificial pneumothorax is a better choice than one lung ventilation (OLV). Obviously, single lumen endotracheal tube is easy for intubation and intraoperative maintenance. Potential problems during intervention include hemodynamic changes, oxygenation, and air embolism. In this paper, present literature is reviewed about two and one lung ventilation in thoracoscopy, looking for clear conclusions for future application.

A comparison between two lung ventilation with CO2 artificial pneumothorax and one lung ventilation during thoracic phase of minimally invasive esophagectomy

Background

To investigate the feasibility and safety of two lung ventilation with artificial pneumothorax in minimally invasive esophagectomy (MIE) through a comparison with conventional one lung ventilation.

Methods

Eleven hundred and sixty-six patients with esophageal cancer, who underwent McKeown MIE in our center from February 2006 to December 2016, were studied retrospectively. Seven hundred and five patients who underwent one lung ventilation with double lumen endotracheal tube (DLET) were assigned to DLET group. Other 461 patients who underwent two lung ventilation with single lumen endotracheal tube (SLET) were assigned to SLET group. Clinical characteristics, surgical variables and complications were compared between two groups.

Results

There were comparable patient characteristics in two groups. Surgical variables and complications were discussed between two groups. SLET group seemed to have shorter operative time, shorter postoperative hospital stay, and more harvested recurrent laryngeal nerve (RLN) lymph nodes than DLET group, which might be attributed to experienced surgeons. However, there were no significant differences of complications between two groups. Intraoperative clinical parameters were further studied. Before intubation and artificial pneumothorax, there were no significant differences between two groups, except diastolic blood pressure (DBP). With the application of artificial pneumothorax, patients in SLET group have obviously higher PO₂, PCO₂, and PetCO₂ value, and slightly lower pH value and blood pressure during thoracic phase. After the thoracic phase, the changes induced by artificial pneumothorax in SLET group were gradually reversed and clinical parameters gradually return to normal level.

Conclusions

Two lung ventilation with artificial pneumothorax is a safe and feasible choice during MIE.

The role of an ambient pressure oxygen source during one-lung ventilation for thoracoscopic surgery

Video-assisted thoracoscopic surgery is facilitated by prompt collapse of the non-ventilated (‘operated’) lung, and interrupted and impeded if there is a need for oxygen (O2) delivery by continuous positive airways pressure in order to manage hypoxaemia. It has been proposed that connecting an ambient pressure O2 source to the airway of the non-ventilated lung at the time one-lung ventilation is initiated and before the chest is opened will, by avoiding entrainment of ambient nitrogen, serve to facilitate lung collapse. It has also been proposed that leaving the O2 source connected will enable, not only ongoing apnoeic oxygenation before the chest is opened, but also the thoracoscopic procedure to commence with the operated lung fully pre-oxygenated (with an inspired oxygen fraction of 1), and apnoeic oxygenation to continue throughout the operative procedure in those patients who exhibit a degree of small airways patency at ambient pressure. In reality, several factors can influence the speed of collapse of the operated lung, and very many factors can influence the incidence of hypoxaemia during one-lung ventilation. It therefore appears unlikely that the necessary evidence to support these proposals will be forthcoming from randomised clinical studies on large numbers of patients. Rather, the necessary evidence may only be provided by specifically designed within-patient clinical measurement studies. Nevertheless, it is argued that, in the meantime, there is already sufficient rationale for an ambient pressure O2 source to be connected to the airway of the non-ventilated lung, and for it to remain connected for the duration of one-lung ventilation.

Real-time ventilation and perfusion distributions by electrical impedance tomography during one-lung ventilation with capnothorax

BACKGROUND

Carbon dioxide insufflation into the pleural cavity, capnothorax, with one-lung ventilation (OLV) may entail respiratory and hemodynamic impairments. We investigated the online physiological effects of OLV/capnothorax by electrical impedance tomography (EIT) in a porcine model mimicking the clinical setting.

METHODS

Five anesthetized, muscle-relaxed piglets were subjected to first right and then left capnothorax with an intra-pleural pressure of 19 cm H2 O. The contra-lateral lung was mechanically ventilated with a double-lumen tube at positive end-expiratory pressure 5 and subsequently 10 cm H2 O. Regional lung perfusion and ventilation were assessed by EIT. Hemodynamics, cerebral tissue oxygenation and lung gas exchange were also measured.

RESULTS

During right-sided capnothorax, mixed venous oxygen saturation (P = 0.018), as well as a tissue oxygenation index (P = 0.038) decreased. There was also an increase in central venous pressure (P = 0.006), and a decrease in mean arterial pressure (P = 0.045) and cardiac output (P = 0.017). During the left-sided capnothorax, the hemodynamic impairment was less than during the right side. EIT revealed that during the first period of OLV/capnothorax, no or very minor ventilation on the right side could be seen (3 ± 3% vs. 97 ± 3%, right vs. left, P = 0.007), perfusion decreased in the non-ventilated and increased in the ventilated lung (18 ± 2% vs. 82 ± 2%, right vs. left, P = 0.03). During the second OLV/capnothorax period, a similar distribution of perfusion was seen in the animals with successful separation (84 ± 4% vs. 16 ± 4%, right vs. left).

CONCLUSION

EIT detected in real-time dynamic changes in pulmonary ventilation and perfusion distributions. OLV to the left lung with right-sided capnothorax caused a decrease in cardiac output, arterial oxygenation and mixed venous saturation.

The application of single-lumen endotracheal tube anaesthesia with artificial pneumothorax in thoracolaparoscopic oesophagectomy

Double-lumen endotracheal tube (DLET) anaesthesia is the commonly used method in minimally invasive oesophagectomy (MIE). However, DLET intubation does have its disadvantages. Firstly, the placement of the DLET needs a skilled anaesthetist with familiarity of the technique and subsequent ability to perform a fibre-optic bronchoscopy for confirmation. Secondly, DLET intubation and one-lung ventilation are associated with numerous complications, including hoarseness, tracheobronchial injury and vocal injury. In this report, a retrospective analysis was performed on 42 consecutive patients who underwent MIE using single-lumen endotracheal tube (SLET) anaesthesia with CO2 artificial pneumothorax compared with 81 patients who underwent the same procedure with DLET intubation. Our findings showed that SLET intubation with artificial pneumothorax by CO2 insufflation is a feasible and safe method for MIE procedures.

Right or left first during bilateral thoracoscopy?

BACKGROUND

Endoscopic thoracic sympathectomy (ETS) is now an established surgical technique for treatment of palmar hyperhidrosis that is performed under general anesthesia with positive pressure ventilation via either an endotracheal tube or a double lumen endobronchial tube. This is a bilateral disease that requires the division of the right and left thoracic sympathetic chain. The aim of this study was to compare the hemodynamic changes using a left capnothorax first versus right a capnothorax first surgical approach using a single lumen endotracheal tube in patients undergoing bilateral ETS. Lung collapse was achieved by carbon dioxide insufflation.

METHODS

Forty patients of both sexes aged 18-30 years and of American Society of Anesthesiologists grade I were randomly assigned to undergo bilateral ETS. Patients were divided into two groups. Group L comprised left capnothorax first, followed by right capnothorax (n = 20). Group R comprised right capnothorax first, followed by left capnothorax (n = 20). The anesthesia technique was standardized for all patients. Cardiovascular variables were determined during the procedure every minute. Statistical analysis was performed by independent-sample t test and Pearson's chi-square test.

RESULTS

There was a significant (P < 0.05) mean percentage decrease in systolic blood pressure in group L compared to group R. Similarly, the mean percentage decrease in diastolic blood pressure in group L was significant compared to group R (P < 0.05). Seven patients in group L developed bradycardia, but this was not found to be statistically significant.

CONCLUSIONS

When the left capnothorax first approach was used, there was significant hypotension, compared to a right capnothorax first thoracoscopy. We thus recommend that right capnothorax should be performed first in cases of bilateral ETS.

Advancements in robotic-assisted thoracic surgery

Advancements in robotic-assisted thoracic surgery present potential advantages for patients as well as new challenges for the anesthesia and surgery teams. This article describes the major aspects of the surgical approach for the most commonly performed robotic-assisted thoracic surgical procedures as well as the pertinent preoperative, intraoperative, and postoperative anesthetic concerns.

Asystole following positive pressure insufflation of right pleural cavity: a case report

INTRODUCTION

Adverse hemodynamic effects with severe bradycardia have been previously reported during positive pressure insufflation of the right thoracic cavity in humans. To the best of our knowledge, this is the first report of asystole during thoracoscopic surgery with positive pressure insufflation.

CASE PRESENTATION

A 63-year-old Caucasian woman developed asystole at the onset of positive pressure insufflation of her right hemithorax during a thoracoscopic single-lung ventilation procedure. Immediate deflation of pleural cavity, intravenous glycopyrrolate and atropine administration returned her heart rhythm to normal sinus rhythm. The surgery proceeded in the absence of positive pressure insufflation without any further complications.

CONCLUSIONS

We discuss the proposed mechanisms of hemodynamic instability with positive pressure thoracic insufflation, and anesthetic and insufflation techniques that decrease the likelihood of adverse hemodynamic events.

Sinus bradycardia following saline irrigation of the pleural cavity during a video-assisted thoracoscopic surgery: A case report

A 43-year-old man underwent lipoma excision operation with video-assisted thoracoscopic surgery (VATS). Upon completion of the surgery, 20degrees C cold saline irrigation was performed to clean the surgical field. During this procedure, a sudden sinus bradycardia (33 beats/min) occurred. After interruption of the irrigation, the normal sinus rhythm returned spontaneously. With the suspicion that the cold saline could have induced the bradycardia, 40degrees C warm saline irrigation was performed; however, the repeat sinus bradycardia occurred again. The saline irrigation was stopped and the heart rate returned to normal. We conclude that although warm saline irrigation is a common practice after surgical procedures to ensure hemostasis and to clean the surgical field, it may induce profound sinus bradycardia.

Impedance cardiography: noninvasive measurement of hemodynamics and thoracic fluid content during endoscopic thoracic sympathectomy

Endoscopic thoracic sympathectomy (ETS) is a minimally invasive procedure for treating palmar hyperhidrosis (PH). Hemodynamic changes are associated with CO(2) insufflation during ETS. In the present study, we examined hemodynamic changes during general anesthesia using impedance cardiography (ICG) monitor. Seventeen adult patients (15 males) scheduled to undergo elective unilateral ETS for treatment of PH were enrolled in the study. Patients with cardiorespiratory diseases were excluded from the study. Their age and weight mean values were 26.5 +/- 5 years, 71.9 +/- 11.5 kg, respectively. Besides routine monitoring, impedance cardiography monitor was used to measure cardiac output (CO), cardiac index (CI), stroke volume (SV), thoracic fluid content (TFC), and systemic vascular resistance (SVR). Three phases were defined for data collection: A, prior to CO(2) insufflation; B during gas insufflation (at 10, 5, and 2 mm Hg intrathoracic pressures); and C, after gas deflation. Repeated-measures analysis of variance (ANOVA) was used for statistical analysis and post hoc Bonferroni test for multiple comparisons of the data obtained. For all comparisons, P < 0.05 was considered significant. Systemic vascular resistance significantly increased at stages B10 and 5 compared with stage A mean value (P < 0.05). CO, CI, and SV mean values decreased significantly at stage B compared with stage A mean values. The mean values of thoracic fluid content at stages A, B10, 5, 2, and C were 33 +/- 5, 30.6 +/- 3.5, 31 +/- 3.4, 31.6 +/- 3.3, and 32.5 +/- 6.8/kOmega, respectively with significant differences (P < 0.05). Significant reductions of cardiac parameters were reported in the present study, but they were of minimal clinical significance. Of interest was the significant reduction of thoracic fluid content during CO(2) insufflation, whether it correlates to the magnitude of compression, caused by CO(2) insufflation accompanied by high systemic vascular resistance or sympathectomy procedure, yet to be further studied.

Anesthetic Considerations for Special Thoracic Procedures

Significant advances have been achieved in surgical and anesthetic techniques for the treatment of patients presenting with a variety of complex intrathoracic lesions. Despite the technologic advances, these patients continue to pose a challenge for anesthesiologists to provide safe and effective clinical care. A thorough understanding of the patient's underlying pathology inclusive of a detailed preoperative evaluation and effective communication between the surgical and anesthesia teams would help to ensure a favorable outcome.