Effects of Intraoperative Ventilation Strategy on Perioperative Atelectasis Assessed by Lung Ultrasonography in Patients Undergoing Open Abdominal Surgery: a Prospective Randomized Controlled Study

Mapping Trends and Hotspots Regarding the Use of Lung Ultrasound in the Field of Anesthesiology: A Bibliometric Analysis of Global Research

Purpose

Lung ultrasound (LUS) is increasingly utilized in the field of anesthesiology due to its focused, quick application and the advantage of not exposing patients to ionizing radiation. This study aims to analyze the status and trends in this area from a macroscopic perspective.

Methods

A bibliometric analysis was conducted using the Web of Science (WoS) Core Collection. The analysis and visualization were performed using WoS, Excel, VOSviewer, and CiteSpace. Parameters such as publications, countries, institutions, journals, and keywords were analyzed.

Results

A total of 133 articles published over the last 10 years were analyzed to clarify the current status and future trends on the use of LUS in anesthesiology. The number of publications increased markedly from May 1, 2014, to April 30, 2024. China is the highest productive country, while the USA had the highest number of citations. In the institution, Seoul National University in South Korea published the most articles and had the highest number of citations. Kim Jin-Tae emerged as the most prolific and influential author. BMC Anesthesiology and the Journal of Cardiothoracic and Vascular Anesthesia were identified as the most popular journals in the field. Keywords such as "atelectasis", "mechanical ventilation", and "pulmonary complications" were closely related to the use of LUS in anesthesiology.

Conclusion

This study provides a comprehensive analysis of research on the use of LUS in anesthesiology, highlighting the growing interest in LUS and its relevance to pulmonary complications.

Effect of visual lung recruitment manoeuvres guided by trans-oesophageal lung ultrasound on atelectasis after thoracoscopic lobectomy: a randomised, single-blind, prospective study

BACKGROUND

Although the incidence of postoperative atelectasis could be reduced using lung recruitment manoeuvres, it remains high. We hypothesised that intraoperative visual lung recruitment guided by trans-oesophageal lung ultrasound would be more effective than the conventional method for managing postoperative atelectasis.

METHODS

In this randomised, controlled, prospective study, 84 patients undergoing thoracoscopic lobectomy were recruited from Affiliated Chengdu Fifth People's Hospital (teaching hospital) in China. Patients were grouped into trans-oesophageal lung ultrasound-guided (Group G, n = 42) and control (Group C, n = 42) groups.

METHODS

Lung recruitment was performed after anaesthesia induction, before chest closure and before the endotracheal tube extubation. In Group C, recruitment pressure was controlled at 30 cm H2O for 10 s (performed thrice); in Group G, the pressure was controlled at 30 cm H2O (performed thrice), and the tidal volume did not exceed 20 ml kg-1 until no atelectasis was detected by trans-oesophageal ultrasound. The primary outcome was lung ultrasound scores measured at the post anaesthesia care unit 30 min after extubation. The secondary outcomes included the oxygenation index (30 min after extubation) and the incidence of atelectasis (30 min after extubation and 3 days after surgery).

RESULTS

The final analysis included 79 patients. The lung ultrasound score was significantly higher in the control group than in the ultrasound-guided group 30 min after extubation (Group C vs. Group G, 8.6 ± 2.6 vs. 6.5 ± 2.0, P < 0.001). No significant difference in the oxygenation indexes 30 min after extubation was observed between the groups (P = 0.074); however, the incidence of atelectasis 30 min after extubation significantly differed between the two groups (Group C vs. Group G, 57% vs. 33%, P = 0.031). The incidence of atelectasis 3 days after surgery did not significantly differ between the two groups (Group C vs. Group G, 45% vs. 28%, P = 0.122).

CONCLUSIONS

Lung recruitment guided by trans-oesophageal lung ultrasound can reduce lung ultrasound scores and the incidence of atelectasis at the post anaesthesia care unit 30 min after extubation. However, it does not significantly reduce the incidence of atelectasis 3 days after surgery. TRIAL REGISTRATION: Registration number: ChiCTR2200062509. Registered on 10 /8/ 2022.

Effect of driving pressure on early postoperative lung gas distribution in supratentorial craniotomy: a randomized controlled trial

BACKGROUND

Neurosurgical patients represent a high-risk population for postoperative pulmonary complications (PPCs). A lower intraoperative driving pressure (DP) is related to a reduction in postoperative pulmonary complications. We hypothesized that driving pressure-guided ventilation during supratentorial craniotomy might lead to a more homogeneous gas distribution in the lung postoperatively.

METHODS

This was a randomized trial conducted between June 2020 and July 2021 at Beijing Tiantan Hospital. Fifty-three patients undergoing supratentorial craniotomy were randomly divided into the titration group or control group at a ratio of 1 to 1. The control group received 5 cmH₂O PEEP, and the titration group received individualized PEEP targeting the lowest DP. The primary outcome was the global inhomogeneity index (GI) immediately after extubation obtained by electrical impedance tomography (EIT). The secondary outcomes were lung ultrasonography scores (LUSs), respiratory system compliance, the ratio of the partial pressure of arterial oxygen to the fraction of inspired oxygen (PaO₂/FiO₂) and PPCs within 3 days postoperatively.

RESULTS

Fifty-one patients were included in the analysis. The median (IQR [range]) DP in the titration group versus the control group was 10 (9-12 [7-13]) cmH₂O vs. 11 (10-12 [7-13]) cmH₂O, respectively (P = 0.040). The GI tract did not differ between groups immediately after extubation (P = 0.080). The LUS_S was significantly lower in the titration group than in the control group immediately after tracheal extubation (1 [0-3] vs. 3 [1-6], P = 0.045). The compliance in the titration group was higher than that in the control group at 1 h after intubation (48 [42-54] vs. 41 [37-46] ml·cmH₂O^-1, P = 0.011) and at the end of surgery (46 [42-51] vs. 41 [37-44] ml·cmH₂O^-1, P = 0.029). The PaO₂/FiO₂ ratio was not significantly different between groups in terms of the ventilation protocol (P = 0.117). At the 3-day follow-up, no postoperative pulmonary complications occurred in either group.

CONCLUSIONS

Driving pressure-guided ventilation during supratentorial craniotomy did not contribute to postoperative homogeneous aeration, but it may lead to improved respiratory compliance and lower lung ultrasonography scores.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov NCT04421976.

Assessment of Perioperative Atelectasis Using Lung Ultrasonography in Patients Undergoing Pneumoperitoneum Surgery in the Trendelenburg Position: Aspects of Differences according to Ventilatory Mode

BACKGROUND

During robotic gynecologic pneumoperitoneum surgery in the Trendelenburg position, aeration loss leads to perioperative atelectasis. Recently developed ventilator mode pressure-controlled ventilation volume-guaranteed (PCV-VG) mode could provide adequate ventilation with lower inspiratory pressure compared to volume-controlled ventilation (VCV); we hypothesized that PCV-VG mode may be beneficial in reducing perioperative atelectasis via low tidal volume (V_T) of 6 mL/kg ventilation during robotic gynecologic pneumoperitoneum surgery in the Trendelenburg position. We applied lung ultrasound score (LUS) for detecting perioperative atelectasis. We aimed to compare perioperative atelectasis between VCV and PCV-VG with a low V_T of 6 mL/kg during pneumoperitoneum surgery in the Trendelenburg position using LUS.

METHODS

Patients scheduled for robotic gynecologic surgery were randomly allocated to the VCV (n = 41) or PCV-VG group (n = 41). LUS, ventilatory, and hemodynamic parameters were evaluated at T1 (before induction), T2 (10 minutes after induction in the supine position), T3 (10 minutes after desufflation of CO₂ in the supine position), and T4 (30 minutes after emergence from anesthesia in the recovery room).

RESULTS

Eighty patients (40 with PCV-VG and 40 with VCV) were included. Demographic data showed no significant differences between the groups. The total LUS has changed from baseline to T4, 0.63 (95% confidence interval [CI], 0.32, 0.94) to 1.77 (95% CI, 1.42, 2.21) in the VCV group and 0.86 (95% CI, 0.56, 1.16) to 1.43 (95% CI, 1.08, 1.78) in the PCV-VG group (P = 0.170). In both groups, total LUS increased significantly compared to the baseline values.

CONCLUSION

Using a low V_T of 6 mL/kg during pneumoperitoneum surgery in the Trendelenburg position, our study showed no evidence that PCV-VG ventilation was superior to VCV in terms of perioperative atelectasis.

TRIAL REGISTRATION

Clinical Research Information Service Identifier: KCT0006404.