Reply to Böning et al. Comment on "Ceruti et al. Temporal Changes in the Oxyhemoglobin Dissociation Curve of Critically Ill COVID-19 Patients. J. Clin. Med. 2022, 11, 788".

We would like to thank Böning et al. for all the important issues raised in the present commentary [...].

Temporal Changes in the Oxyhemoglobin Dissociation Curve of Critically Ill COVID-19 Patients.

Critical COVID-19 is a life-threatening disease characterized by severe hypoxemia with complex pathophysiological mechanisms that are not yet completely understood. A pathological shift in the oxyhemoglobin curve (ODC) was previously described through the analysis of p50, intended as the oxygen tension at which hemoglobin is saturated by oxygen at 50%. The aim of this study was to analyze Hb-O2 affinity features over time in a cohort of critically ill COVID-19 patients, through the analysis of ODC p50 behavior. A retrospective analysis was performed; through multiple arterial blood gas (ABG) analyses, each p50 was calculated and normalized according to PaCO2, pH and temperature; patients' p50 evolution over time was reported, comparing the first 3 days (early p50s) with the last 3 days (late p50s) of ICU stay. A total of 3514 ABG analyses of 32 consecutive patients were analyzed. The majority of patients presented a left shift over time (p = 0.03). A difference between early p50s and late p50s was found (20.63 ± 2.1 vs. 18.68 ± 3.3 mmHg, p = 0.03); median p50 of deceased patients showed more right shifts than those of alive patients (24.1 vs. 18.45 mmHg, p = 0.01). One-way ANOVA revealed a p50 variance greater in the early p50s (σ2 = 8.6) than in the late p50s (σ2 = 3.84), associated with a reduction over time (p < 0.001). Comparing the Hb-O2 affinity in critically ill COVID-19 patients between ICU admission and ICU discharge, a temporal shift in the ODC was observed.

Pseudoatrial Flutter: When the Problem Lies Outside the Heart.

Electrocardiogram (ECG) artifacts are a common problem in emergency medicine. Generally these artifacts are induced by movement disorders, which generate electrical interference with the ECG recording. If these disorders are not promptly recognized, consequences can lead to hospitalization and execution of unnecessary diagnostic tests, thereby increasing the costs and clinical risks such as nosocomial infections and thromboembolism. We present a pseudoatrial flutter generated by a Parkinson's-like movement.

Risk factors for postoperative recurrence of spontaneous pneumothorax treated by video-assisted thoracoscopic surgery†.

OBJECTIVES: Over the past two decades, video-assisted thoracoscopic blebectomy and pleurodesis have been used as a safe and reliable option for treatment of spontaneous pneumothorax. The aim of this study is to evaluate the long-term outcome of video-assisted thoracoscopic surgery (VATS) treatment of spontaneous pneumothorax in young patients, and to identify risk factors for postoperative recurrence. METHODS: We retrospectively analysed the outcome of VATS treatment of spontaneous pneumothorax in our institution in 150 consecutive young patients (age ≤ 40 years) in the years 1997-2010. Treatment consisted of stapling blebectomy and partial parietal pleurectomy. After excluding 16 patients lost to follow-up, in 134 cases [110 men, 24 women; mean age, 25 ± 7 standard deviation years; median follow-up, 79 months (range: 36-187 months)], we evaluated postoperative complications, focusing on pneumothorax recurrence, thoracic dysaesthesia and chronic chest pain. Risk factors for postoperative pneumothorax recurrence were analysed by logistic regression. RESULTS: Of 134 treated patients, 3 (2.2%) required early reoperation (2 for bleeding; 1 for persistent air leaks). Postoperative (90-day) mortality was nil. Ipsilateral pneumothorax recurred in 8 cases (6.0%) [median time of recurrence, 43 months (range: 1-71 months)]. At univariate analysis, the recurrence rate was significantly higher in women (4/24) than in men (4/110; P = 0.026) and in patients with >7-day postoperative air leaks (P = 0.021). Multivariate analysis confirmed that pneumothorax recurrence correlated independently with prolonged air leaks (P = 0.037) and with female gender (P = 0.045). Chronic chest wall dysaesthesia was reported by 13 patients (9.7%). In 3 patients, (2.2%) chronic thoracic pain (analogical score >4) was recorded, but only 1 patient required analgesics more than once a month. CONCLUSIONS: VATS blebectomy and parietal pleurectomy is a safe procedure for treatment of spontaneous pneumothorax in young patients, with a 6% long-term recurrence rate in our experience. Postoperative recurrence significantly correlates with female gender and with prolonged air leakage after surgery.

The proangiogenic phenotype of natural killer cells in patients with non-small cell lung cancer.

The tumor microenvironment can polarize innate immune cells to a proangiogenic phenotype. Decidual natural killer (dNK) cells show an angiogenic phenotype, yet the role for NK innate lymphoid cells in tumor angiogenesis remains to be defined. We investigated NK cells from patients with surgically resected non-small cell lung cancer (NSCLC) and controls using flow cytometric and functional analyses. The CD56(+)CD16(-) NK subset in NSCLC patients, which represents the predominant NK subset in tumors and a minor subset in adjacent lung and peripheral blood, was associated with vascular endothelial growth factor (VEGF), placental growth factor (PIGF), and interleukin-8 (IL-8)/CXCL8 production. Peripheral blood CD56(+)CD16(-) NK cells from patients with the squamous cell carcinoma (SCC) subtype showed higher VEGF and PlGF production compared to those from patients with adenocarcinoma (AdC) and controls. Higher IL-8 production was found for both SCC and AdC compared to controls. Supernatants derived from NSCLC CD56(+)CD16(-) NK cells induced endothelial cell chemotaxis and formation of capillary-like structures in vitro, particularly evident in SCC patients and absent from controls. Finally, exposure to transforming growth factor-ß(1) (TGFß(1)), a cytokine associated with dNK polarization, upregulated VEGF and PlGF in peripheral blood CD56(+)CD16(-) NK cells from healthy subjects. Our data suggest that NK cells in NSCLC act as proangiogenic cells, particularly evident for SCC and in part mediated by TGFß(1).

Bronchogenic cyst associated with pericardial defect: case report and review of the literature.

Partial defect of the pericardium combined with bronchogenic cyst is a very rare congenital anomaly. We describe the case of a 32-year-old man with a partial defect of the left pericardium and a bronchogenic cyst arising from the border of the pericardial defect. The cyst was successfully resected with the harmonic scalpel by three-port videothoracoscopic approach.