Use of pressure-regulated volume control in the first 48 hours of hospitalization of mechanically ventilated patients with sepsis or septic shock, with or without ARDS

Comparison of Ventilation Strategies Across the Perioperative Period in Patients Undergoing General Anesthesia: A Narrative Review

General anesthesia is a critical component of surgical procedures, requiring effective ventilation strategies to ensure adequate oxygenation and prevent complications. This narrative review aims to compare various ventilation techniques used during general anesthesia, focusing on their physiological foundations, clinical applications, and outcomes. Traditional methods, such as high tidal volume ventilation, have evolved into more sophisticated approaches, including protective lung ventilation, which are particularly beneficial for high-risk patients with respiratory comorbidities. The review highlights that protective lung ventilation, characterized by lower tidal volumes and optimal positive end-expiratory pressure, is associated with improved oxygenation, reduced incidence of post-operative pulmonary complications, and enhanced overall recovery. Despite the advantages of personalized ventilation approaches, current evidence remains limited by small sample sizes and variability in study designs. This underscores the need for larger, randomized controlled trials to establish definitive guidelines. Future research should also explore emerging technologies to optimize the real-time management of ventilation parameters. The findings emphasize the importance of individualized ventilation strategies in clinical practice to improve patient outcomes and inform policy development. By advancing our understanding of ventilation techniques, this review aims to contribute to safer anesthesia practices and enhance recovery in surgical patients.

Adaptive Pressure Control-Continuous Mandatory Ventilation Versus Volume Control-Continuous Mandatory Ventilation: Factors Associated With Initiation, Maintenance, and Adjustment

BACKGROUND

Adaptive pressure control-continuous mandatory ventilation (APC-CMV) is a frequently utilized ventilator mode in ICU settings. This analysis compared APC-CMV and traditional volume control-continuous mandatory ventilation (VC-CMV) mode, describing factors associated with initiation, maintenance, and changes in settings of each mode.

METHODS

We analyzed ventilator data from a retrospective electronic health record data set collected as part of a quality improvement project in a single academic ICU. The majority ventilator mode was defined as the mode comprising the highest proportion of mechanical ventilation time. Multivariable logistic regression was used to identify variables associated with initial and majority APC-CMV or VC-CMV modes. Wilcoxon rank-sum tests were used to compare ventilator setting changes/d and sedation as a function of APC-CMV and VC-CMV majority modes.

RESULTS

Among 1,213 subjects initiated on mechanical ventilation from January 2013-March 2017, 68% and 24% were initiated on APC-CMV and VC-CMV, respectively, which composed 62% and 21% of the majority ventilator modes. Age, sex, race, and ethnicity were not associated with the initial or majority APC-CMV or VC-CMV modes. Subjects initiated on APC-CMV spent 88% of the mechanical ventilation time on APC-CMV mode. Compared to VC-CMV, subjects with APC-CMV majority mode experienced more ventilator setting changes/d (1.1 vs 0.8, P < .001). There were no significant differences in sedative medications when comparing subjects receiving APC-CMV versus VC-CMV majority modes.

CONCLUSIONS

APC-CMV was highly utilized in the medical ICU. Subjects on APC-CMV had more ventilator setting changes/d than those on VC-CMV. APC-CMV offered no advantage of reduced setting adjustments or less sedation compared to VC-CMV.

Effect of Ventilator Mode on Ventilator-Free Days in Critically Ill Adults: A Randomized Trial

Rationale

For critically ill adults receiving invasive mechanical ventilation, the ventilator mode determines how breaths are delivered. Whether the choice of ventilator mode affects outcomes for critically ill patients is unknown. To compare the effects of three common ventilator modes (volume control, pressure control, and adaptive pressure control) on death and duration of mechanical ventilation.

Methods

We conducted a pragmatic, cluster-randomized, crossover trial among adults receiving invasive mechanical ventilation in a medical ICU between November 1, 2022 and July 31, 2023. Each month, patients in the participating unit were assigned to receive volume control, pressure control, or adaptive pressure control during continuous mandatory ventilation. The primary outcome was ventilator-free days through 28 days.

Results

Among 566 patients included in the primary analysis, the median number of ventilator-free days was 23 [IQR, 0-26] in the volume control group, 22 [0-26] in the pressure control group, and 24 [0-26] in the adaptive pressure control group (P=0.60). The median tidal volume was similar in the three groups, but the percentage of breaths larger than 8mL/kg of predicted body weight differed between volume control (median, 4.0%; IQR, 0.0-14.1), pressure control (10.6%; 0.0-31.5), and adaptive pressure control (4.7%; 0.0-19.2). Incidences of hypoxemia, acidemia, and barotrauma were similar in the three groups.

Conclusions

Among critically ill adults receiving invasive mechanical ventilation, the use of volume control, pressure control, or adaptive pressure control did not affect the number of ventilator-free days, however, confidence intervals included differences that may be clinically meaningful.

Smoking on the risk of acute respiratory distress syndrome: a systematic review and meta-analysis

BACKGROUND

The relationship between smoking and the risk of acute respiratory distress syndrome (ARDS) has been recognized, but the conclusions have been inconsistent. This systematic review and meta-analysis investigated the association between smoking and ARDS risk in adults.

METHODS

The PubMed, EMBASE, Cochrane Library, and Web of Science databases were searched for eligible studies published from January 1, 2000, to December 31, 2023. We enrolled adult patients exhibiting clinical risk factors for ARDS and smoking condition. Outcomes were quantified using odds ratios (ORs) for binary variables and mean differences (MDs) for continuous variables, with a standard 95% confidence interval (CI).

RESULTS

A total of 26 observational studies involving 36,995 patients were included. The meta-analysis revealed a significant association between smoking and an increased risk of ARDS (OR 1.67; 95% CI 1.33-2.08; P < 0.001). Further analysis revealed that the associations between patient-reported smoking history and ARDS occurrence were generally similar to the results of all the studies (OR 1.78; 95% CI 1.38-2.28; P < 0.001). In contrast, patients identified through the detection of tobacco metabolites (cotinine, a metabolite of nicotine, and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL), a metabolite of tobacco products) showed no significant difference in ARDS risk (OR 1.19; 95% CI 0.69-2.05; P = 0.53). The smoking group was younger than the control group (MD - 7.15; 95% CI - 11.58 to - 2.72; P = 0.002). Subgroup analysis revealed that smoking notably elevated the incidence of ARDS with extrapulmonary etiologies (OR 1.85; 95% CI 1.43-2.38; P < 0.001). Publication bias did not affect the integrity of our conclusions. Sensitivity analysis further reinforced the reliability of our aggregated outcomes.

CONCLUSIONS

There is a strong association between smoking and elevated ARDS risk. This emphasizes the need for thorough assessment of patients' smoking status, urging healthcare providers to vigilantly monitor individuals with a history of smoking, especially those with additional extrapulmonary risk factors for ARDS.