A comparison of the effects of manual hyperinflation and ventilator hyperinflation on restoring end-expiratory lung volume after endotracheal suctioning: A pilot physiologic study

Dynamic inflation prevents and standardized lung recruitment reverts volume loss associated with percutaneous tracheostomy during volume control ventilation: results from a Neuro-ICU population

To determine how percutaneous tracheostomy (PT) impacts on respiratory system compliance (Crs) and end-expiratory lung volume (EELV) during volume control ventilation and to test whether a recruitment maneuver (RM) at the end of PT may reverse lung derecruitment. This is a single center, prospective, applied physiology study. 25 patients with acute brain injury who underwent PT were studied. Patients were ventilated in volume control ventilation. Electrical impedance tomography (EIT) monitoring and respiratory mechanics measurements were performed in three steps: (a) baseline, (b) after PT, and (c) after a standardized RM (10 sighs of 30 cmH2O lasting 3 s each within 1 min). End-expiratory lung impedance (EELI) was used as a surrogate of EELV. PT determined a significant EELI loss (mean reduction of 432 arbitrary units p = 0.049) leading to a reduction in Crs (55 ± 13 vs. 62 ± 13 mL/cmH2O; p < 0.001) as compared to baseline. RM was able to revert EELI loss and restore Crs (68 ± 15 vs. 55 ± 13 mL/cmH2O; p < 0.001). In a subgroup of patients (N = 8, 31%), we observed a gradual but progressive increase in EELI. In this subgroup, patients did not experience a decrease of Crs after PT as compared to patients without dynamic inflation. Dynamic inflation did not cause hemodynamic impairment nor raising of intracranial pressure. We propose a novel and explorative hyperinflation risk index (HRI) formula. Volume control ventilation did not prevent the PT-induced lung derecruitment. RM could restore the baseline lung volume and mechanics. Dynamic inflation is common during PT, it can be monitored real-time by EIT and anticipated by HRI. The presence of dynamic inflation during PT may prevent lung derecruitment.

Optimization of lung ultrasound in ultrafast-track anesthesia for non-cyanotic congenital heart disease surgery

Objective

We aimed to explore the feasibility of lung ultrasound for perioperative assessment and the optimal effect of lung ultrasound in reducing lung complications during non-cyanotic congenital heart disease (CHD) surgery using ultrafast-track anesthesia.

Methods

Sixty patients were treated at Shenzhen Children's Hospital between 2019 and 2020. Of these, 30 patients in group N had an indication for extubation and ultrafast-track anesthesia after congenital heart surgery; the tracheal catheter was removed, and the patients were sent to the cardiac intensive care unit (CICU) for further monitoring and treatment. Another 30 patients were in group L and also had an indication for extubation and ultrafast-track anesthesia; in addition we compared lung ultrasound score (LUS) before and after surgery, when we found the cases that LUS ≥ 15, for whom targeted optimization treatment would be carried out. The tracheal catheter was removed after LUS <15 days before the patients were sent to the CICU. In all cases, the LUS and PaO2/FiO2 ratios (P/F) of both groups were recorded at the time of anesthesia induction (T0), before extubation (T1), and 5 min (T2), 1 h (T3), and 24 h (T4) after extubation. The incidence of pulmonary complications, LUS, and P/F were compared between the two groups.

Results

There was great consistency between LUS and radiographic findings. Comparing the data of the two groups at T2, T3 and T4, the P/F was higher and the LUS was lower in group L than in group N. The incidence of lung complications in group L (18 cases, 60 %) was lower than that in group N (26 cases, 86.7 %, χ2 = 5.46, P = 0.02); comparing LUS between T0 and T3, LUS decreased in a greater number of cases in group L (15, 50 %) than in group N (7 cases, 23.3 %, χ2 = 4.59, P = 0.032).

Conclusion

Lung ultrasonography can effectively help assess lung conditions. Optimization guided by lung ultrasound in ultrafast track anesthesia can significantly reduce postoperative lung complications.

An Update on Cardiorespiratory Physiotherapy during Mechanical Ventilation

Physiotherapists are integral members of the multidisciplinary team managing critically ill adult patients. However, the scope and role of physiotherapists vary widely internationally, with physiotherapists in some countries moving away from providing early and proactive respiratory care in the intensive care unit (ICU) and focusing more on early mobilization and rehabilitation. This article provides an update of cardiorespiratory physiotherapy for patients receiving mechanical ventilation in ICU. Common and some more novel assessment tools and treatment options are described, along with the mechanisms of action of the treatment options and the evidence and physiology underpinning them. The aim is not only to summarize the current state of cardiorespiratory physiotherapy but also to provide information that will also hopefully help support clinicians to deliver personalized and optimal patient care, based on the patient's unique needs and guided by accurate interpretation of assessment findings and the current evidence. Cardiorespiratory physiotherapy plays an essential role in optimizing secretion clearance, gas exchange, lung recruitment, and aiding with weaning from mechanical ventilation in ICU. The physiotherapists' skill set and scope is likely to be further optimized and utilized in the future as the evidence base continues to grow and they get more and more integrated into the ICU multidisciplinary team, leading to improved short- and long-term patient outcomes.

Comparison of Positive End-Expiratory Pressure versus Tidal Volume-Induced Ventilator-Driven Alveolar Recruitment Maneuver in Robotic Prostatectomy: A Randomized Controlled Study

Background: We evaluated the pulmonary effects of two ventilator-driven alveolar recruitment maneuver (ARM) methods during laparoscopic surgery. Methods: Sixty-four patients undergoing robotic prostatectomy were randomized into two groups: incrementally increasing positive end-expiratory pressure in a stepwise manner (PEEP group) versus tidal volume (V_T group). We performed each ARM after induction of anesthesia in the supine position (T1), after pneumoperitoneum in the Trendelenburg position (T2), and after peritoneum desufflation in the supine position (T3). The primary outcome was change in end-expiratory lung impedance (EELI) before and 5 min after ARM at T3, measured by electrical impedance tomography. Results: The PEEP group showed significantly higher increasing EELI 5 min after ARM than the V_T group at T1 and T3 (median [IQR] 460 [180,800] vs. 200 [80,315], p = 0.002 and 280 [170,420] vs. 95 [55,175], p = 0.004, respectively; PEEP group vs. V_T group). The PEEP group showed significantly higher lung compliance and lower driving pressure at T1 and T3. However, there was no significant difference in EELI change, lung compliance, or driving pressure after ARM at T2. Conclusions: The ventilator-driven ARM by the increasing PEEP method led to greater improvements in lung compliance at the end of laparoscopic surgery than the increasing V_T method.