Evaluation of the Efficacy of Budesonide Combined with Pulmonary Surfactants on the Neonatal Respiratory Distress Syndrome by Pulmonary Ultrasonography

Objective. This study aimed to investigate the value of lung ultrasound images in evaluating the efficacy of budesonide combined with pulmonary surfactant (PS) in the treatment of neonatal respiratory distress syndrome (NRDS) in premature infants. Methods. 76 NRDS premature infants admitted to the hospital were randomly divided into experimental group and control group, with 38 children in each group. The premature infants in control group underwent PS, and those in experimental group underwent budesonide combined with PS. After treatment, lung ultrasound imaging was used to evaluate the curative effect, and X-ray results were used as a reference. The changes in clinical signs of two groups were detected, and the pulmonary ultrasound was used to evaluate the clinical efficacy of two groups. The changes in the lung ultrasound score (LUS) and arterial blood gas (ABG) indexes of two groups were compared before and after treatment. Results. LUS and improvement of patients of experimental group were obviously higher than those of the control group after treatment. LUS of experimental group was 12.1 ± 3.7, and that of control group was 18.2 ± 2.3, respectively. The differences were statistically significant ( P < 0.05). The arterial partial oxygen pressure (PaO2) and oxygenation index (PaO2/FiO2) levels of two groups of patients increased dramatically after treatment. PaO2 and PaO2/FiO2 levels of experimental group were 65.59 ± 12.46 mmHg and 112.57 ± 19.3 mmHg, and those of control group were 45.12 ± 11.21 mmHg and 101.28 ± 21.36 mmHg, respectively. However, arterial partial pressure of carbon dioxide (PaCO2) level was significantly decreased in two groups after treatment. PaCO2 level of experimental group was 40.24 ± 8.92 mmHg, and that of control group was 41.22 ± 9.24 mmHg, respectively ( P < 0.05). The diagnostic accuracy of lung ultrasound images in two groups was 95.3% and 96.2%, respectively. Conclusion. Pulmonary ultrasonography showed a high diagnostic accuracy in evaluating the efficacy of budesonide combined with PS in the treatment of NRDS in premature infants. It can evaluate the cardiopulmonary function of premature infants with NRDS and effectively improve the respiratory status of premature infants. In conclusion, this study provided some reference value for upgrading the clinical treatment of NRDS in premature infants.

The Correlation between Intra-Arterial Partial Pressure of CO2 (PaCO2) and Post-Operative Nausea, Vomiting (PONV) and Pain in Patients Undergoing Laparoscopic Cholecystectomy

Background: Postoperative nausea and vomiting is a common complication after surgery that no single theory has been expressed as to the cause of this complication so far. The aim of this study was to determine the relationship between PaCO2 and nausea, vomiting and pain after laparoscopic cholecystectomy. Methods: In this cross-sectional study, 88 patients in Alzahra hospital, underwent laparoscopic cholecystectomy were selected and the level of pre and postoperative PaCO2, as well as duration of postoperative nausea, incidence of vomiting, and severity of postoperative pain was assessed. The correlation between PaCO2, HCO3 and PH with these postoperative complications were evaluated. The patients’ data were analyzed by using Chi-square, t-test, Pearson correlation, Paired t-test and Repeated Measure ANOVA tests. P value < 0.05 was considered statistically significant. Results: The correlation between duration of nausea and PaCO2 levels before and after surgery was 0.05 and 0.04, respectively, which was not statistically significant (p value = 0.63 and p value = 0.72, respectively). In addition, the correlation between PaCO2 level and severity of postoperative pain was 0.2 (p value = 0.07), which was not statistically significant. Conclusion: The findings of the present study showed that PaCO2 level has not statistically significant effect on duration of postoperative nausea, incidence of vomiting, and severity of postoperative pain.

Assessment of Nocturnal Hypoventilation by Different Methods and Definitions in Children with Neuromuscular Disease: Oxycapnography and Blood Gas Analysis

Objective: To investigate whether partial arterial carbon dioxide pressure (PaCO2) level in arterial blood gas analysis that was used to predict nocturnal hypoventilation (NH) is concordant with nocturnal end-tidal CO2 (PetCO2) measurement obtained by a noninvasive method of oxycapnography in children with neuromuscular disease (NMD). Methods: Twenty-one patients aged 6-18 years with a confirmed diagnosis of NMD were enrolled. Each patient underwent a nocturnal oxycapnography study using an orinasal probe and a pulse oximetry finger probe to record PetCO2, oxygen saturation (SpO2), pulse rate, and respiratory rate. Arterial blood gas analysis was performed to record PaCO2 levels on three occasions at night (23: 00 pm, 03: 00 am, 07: 00 am). Results: The mean overnight PaCO2 level of the three blood gas analyses (mean PaCO2noct) was 41.78±4.69 mmHg. A significant change was observed between mean PaCO2 23: 00 and PaCO2 07: 00 levels (p=0.032). There was no significant difference between PaCO2, PetCO2, and SpO2 levels in the NMD group. The interclass correlation coefficient between PaCO2 07: 00 and PetCO2 levels was 0.791 (95% CI: 0.533-0.923); the interclass correlation coefficient between overnight mean PaCO2 and PetCO2 levels was 0.811 (95% CI: 0.533-0.923). Conclusion: Our study indicates that nocturnal PetCO2 and PaCO2 levels were statistically comparable but the use of PaCO2 alone is not adequate to make an early diagnosis of NH in NMD. There is a need for making more restrictive definitions for NH, and conducting studies with larger study populations to reach an agreement on the best definition of hypoventilation, and updating consensus guidelines.

Interstitial lung opacities in patients with severe COVID-19 pneumonia by bedside high-resolution ultrasound in association to CO2 retention

BACKGROUND: Coronavirus disease 2019 (COVID-19) can cause acute respiratory distress Syndrome (ARDS). OBJECTIVE: This single centre cross-section study aimed to grade the severity of pneumonia by bed-side lung ultrasound (LUS). METHODS: A scoring system discriminates 5 levels of lung opacities: A-lines (0 points),≥3 B-Line (1 point), coalescent B-Lines (2 points), marked pleural disruptions (3 points), consolidations (4 points). LUS (convex 1–5 MHz probe) was performed at 6 defined regions for each hemithorax either in supine or prone position. A lung aeration score (LAS, maximum 4 points) was allocated for each patient by calculating the arithmetic mean of the examined lung areas. Score levels were correlated with ventilation parameters and laboratory markers. RESULTS: LAS of 20 patients with ARDS reached from 2.58 to 3.83 and was highest in the lateral right lobe (Mean 3.67). Ferritin levels (Mean 1885μg/l; r = 0.467; p = 0.051) showed moderate correlation in spearman roh calculation. PaCO2 level (Mean 46.75 mmHg; r = 0.632; p = 0.005) correlated significantly with LAS, while duration of ventilation, Horovitz-Index, CRP, LDH and IL-6 did not. CONCUSIONS: The proposed LAS describes severity of lung opacities in COVID-19 patients and correlates with CO2 retention in patients with ARDS.

Factors for Predicting Noninvasive Ventilation Failure in Elderly Patients with Respiratory Failure

Noninvasive ventilation (NIV) is useful when managing critically ill patients. However, it is not easy to apply to elderly patients, particularly those with pneumonia, due to the possibility of NIV failure and the increased mortality caused by delayed intubation. In this prospective observational study, we explored whether NIV was appropriate for elderly patients with pneumonia, defined factors that independently predicted NIV failure, and built an optimal model for prediction of such failure. We evaluated 78 patients with a median age of 77 years. A low PaCO2 level, a high heart rate, and the presence of pneumonia were statistically significant independent predictors of NIV failure. The predictive power for NIV failure of Model III (pneumonia, PaCO2 level, and heart rate) was better than that of Model I (pneumonia alone). Considering the improvement in parameters, patients with successful NIV exhibited significantly improved heart rates, arterial pH and PaCO2 levels, and patients with NIV failure exhibited a significantly improved PaCO2 level only. In conclusion, NIV is reasonable to apply to elderly patients with pneumonia, but should be done with caution. For the early identification of NIV failure, the heart rate and arterial blood gas parameters should be monitored within 2 h after NIV commencement.

Gas Exchange of prone positioning in influenza pneumonia-related acute respiratory distress syndrome: A multicenter retrospective cohort study in Taiwan

Background: Prone positioning has demonstrated decreased mortality in severe acute respiratory distress syndrome (ARDS) patients. The aim of this study was to investigate the effect of prone positioning in patients with influenza pneumonia-related severe ARDS. Methods: This retrospective study includes eight tertiary referral centers. All the patients with influenza pneumonia induced severe ARDS and receiving prone positioning were enrolled. Demographic data, laboratory data, treatment record, ventilator setting data and outcomes were collected. PaO2 responders were defined as the PaO2/FiO2 ratio increasing by ≥20% or ≥20 mm Hg, while PaCO2 responders were defined as PaCO2 decreasing by ≥1 mm Hg after prone positioning for one day. Results: Sixty-five patients receiving prone positioning were enrolled, with 37 (57%) were PaO2 responders and 33 (51%) were PaCO2 responders. Mortality rates were not significantly different between responders and non-responders. PaCO2 responder survivors had significantly shortened length of stay at the ICU (21.0 ± 13.5 vs. 31.7 ± 18.5 days, P = 0.038) and hospital (30.2 ± 16.6 vs. 43.0 ± 16.3 days, P = 0.013) than did non-responders. Multivariate analysis revealed younger age (odds ratio 0.903, 95% confidence interval 0.824-0.989; P = 0.028) and higher PaCO2 level before prone positioning (odds ratio 1.121 confidence interval 1.020-1.231; P = 0.017) were the predictors of PaCO2 responders. Conclusions: In this multicenter retrospective cohort study of influenza pneumonia patients with severe ARDS receiving prone positioning, PaCO2 responders had modestly better clinical outcomes. Younger age and higher PaCO2 level before prone positioning were the predictors of PaCO2 responders. Keywords: Prone positioning, Acute Respiratory Distress Syndrome, Influenza, Gas exchange, Outcome

Effect of inspired CO2 on ventilation and perfusion heterogeneity in hyperventilated dogs

We studied the effect of inspired CO2 on ventilation-perfusion (VA/Q) heterogeneity in dogs hyperventilated under two different tidal volume (VT) and respiratory rate conditions with the use of the multiple inert gas elimination technique. Dogs anesthetized with pentobarbital sodium were hyperventilated with an inspired fraction of O2 of 0.21 by using an increased VT (VT = 30 ml/kg at 18 breaths/min) or an increased respiratory rate (VT = 18 ml/kg at 35 breaths/min). The arterial CO2 tension (PaCO2) was varied to three levels (20, 35, and 52 Torr) by altering the inspired PCO2. The orders of type of ventilation and PaCO2 level were randomized. Compared with normocapnia, VA/Q heterogeneity was increased during hypocapnia induced by increased respiratory rate ventilation, which was indicated by an increase in dispersion indexes and arterial-alveolar inert gas partial pressure difference areas (P < 0.01). In contrast, VA/Q heterogeneity was not affected by hypocapnia when a large VT ventilation was used. Under the conditions of our study, hypercapnia did not result in statistically significant changes in VA/Q heterogeneity with either type of ventilation. Increased VT ventilation reduced dead space at all PaCO2 levels (P < 0.01) and reduced the log standard deviation of the ventilation distribution during normocapnia (P < 0.05) and hypocapnia (P < 0.01). We conclude that hypocapnia increased VA/Q heterogeneity when hyperventilation was achieved with a rapid respiratory rate. Therefore, a lack of improvement in VA/Q matching with inhaled CO2 may be associated with the use of a large VT. These data suggest that hypocapnic bronchoconstriction may be important in mediating hypocapnia-induced VA/Q inequality in dogs.