Respiratory care最新文献

Background: The global population is aging, and the proportion of elderly patients admitted to ICUs is increasing. In this scenario, achieving a balance between judicious utilization of a limited and high-cost resource and providing optimal intensity of care presents a challenge given that in very elderly patients the value of ICU care is uncertain. The aim of our study was to evaluate the survival of older subjects admitted to ICU who require mechanical ventilation at different levels of treatment intensity. Methods: A comprehensive longitudinal ICU database was retrospectively analyzed at a single tertiary center, from January 2008-December 2014, of ICU subjects 80 y old or older who required mechanical ventilation. Results: From January 2009-December 2014, 482 subjects were admitted to the ICU and required mechanical ventilation. Among them, 376 (78%) were age 80-89 y; and 106 (22%) were age ≥ 90 y, with a mean age of 85.84 (4.56). The mean Acute Physiology and Chronic Health Evaluation (APACHE) II score was 21.53 (7.42), and the mean Sequential Organ Failure Assessment score was 5.75 (3.38). The total mortality during ICU admission was 46%, and the hospital mortality was 58%. Only age higher than 90 y (1.41 [1.05-1.91], P = .02) and APACHE score (1.03 [1.01-1.05], P < .001) were associated with mortality after adjustments. The Therapeutic Intervention Scoring System score was analyzed in tertiles and was not related to mortality in univariate analysis or after adjustments. Conclusions: Our data indicate that in older subjects who received mechanical ventilation higher intensity of treatment does not seem to translate into a survival benefit. This finding highlights the importance of considering individualized treatment plans for elderly patients in the ICU.

Background: Mechanical power (MP) applied to the respiratory system (MP_RS) is associated with ventilator-induced lung injury (VILI) and ARDS mortality. Absent automated ventilator MP_RS measurements, the alternative is clinically unwieldy equations. However, simplified surrogate formulas are now available and accurately reflect values produced by airway pressure-volume curves. This retrospective, observational study examined whether the surrogate pressure -control equation alone could accurately assess mortality risk in subjects with ARDS managed almost exclusively with volume control (VC) ventilation. Methods: Nine hundred and forty-eight subjects were studied in whom invasive mechanical ventilation and implementation of ARDS Network ventilator protocols commenced ≤ 24 h after ARDS onset and who survived > 24 h. MP_RS was calculated as 0.098 x breathing frequency x tidal volume x (PEEP + driving pressure). MP_RS was assessed as a risk factor for hospital mortality and compared between non-survivors and survivors across Berlin definition classifications. In addition, mortality was compared across 4 MP_RS thresholds associated with VILI or mortality (ie, 15, 20, 25, and 30 J/min). Results: MP_RS was associated with increased mortality risk: odds ratio (95% CI) of 1.06 (1.04-1.07) J/min (P < .001). Median MP_RS differentiated non-survivors from survivors in mild (24.7 J/min vs 18.5 J/min, respectively, P = .034), moderate (25.7 J/min vs 21.3 J/min, respectively, P < .001), and severe ARDS (28.7 J/min vs 23.5 J/min, respectively, P < .001). Across 4 MP_RS thresholds, mortality increased from 23-29% when MP_RS was ≤ threshold versus 38-51% when MP_RS was > threshold (P < .001). In the > cohort, the odds ratio (95% CI) increased from 2.03 (1.34-3.12) to 2.51 (1.87-3.33). Conclusion: The pressure control surrogate formula is sufficiently accurate to assess mortality in ARDS, even when using VC ventilation. In our subjects when MP_RS exceeds established cutoff values for VILI or mortality risk, we found mortality risk consistently increased by a factor of > 2.0.

Background: High-flow nasal cannula (HFNC) is an oxygen therapy delivery method used with severely ill patients. The literature regarding the effects of HFNC on overall swallowing function and aspiration risk is limited, and results from current studies are mixed. This study aimed to investigate the possible association between HFNC and swallowing impairment. Methods: This was a single-center, within-subjects, repeated-measures retrospective study of 21 hospitalized subjects. Participants underwent flexible endoscopic evaluation of swallowing (FEES) while receiving oxygen therapy via HFNC and had another instrumented swallow assessment, a FEES or a modified barium swallow study, when they no longer required HFNC oxygen. Three markers of swallowing function were extracted from reports-aspiration, silent aspiration, and overall swallowing function, and statistical analyses were conducted to assess their relationship to HFNC status. Results: There was a statistically significant difference in the proportion of subjects who aspirated while they were receiving oxygen via HFNC as compared to when they were not on HFNC (P = .033). When on HFNC, 61.9% (13/21) of subjects had an aspiration event during instrumented swallow evaluation; and when off HFNC, 23.8% (5/21) of subjects aspirated. Findings related to silent aspiration during instrumented swallowing evaluation were not significant (P = .32). When subjects were on HFNC, their overall swallowing function was significantly more impaired than when they were off HFNC (P < .001). Conclusions: The results of this study indicate that HFNC is a factor to consider when determining if a patient is appropriate for oral alimentation. Given the limited data on HFNC and swallowing function and the fragility of this population, instrumented examination of swallowing prior to initiation of oral intake may be beneficial. Future prospective studies with larger populations that stratify subjects into risk categories based on subject characteristics and pathophysiology are needed.

Background: Resuscitator bags are commonly utilized in acute care settings; however, poor performance occurs irrespective of a provider's qualifications or experience. A new flow-limiting device (Sotair by SafeBVM, Boston, Massachusetts) limits inspiratory flow during manual ventilation, thus minimizing peak inspiratory pressures. This study examined the differences in flow, pressure, and tidal volume (V_T) during ventilation with a manual resuscitator connected to the flow-limiting device versus a mechanical ventilator. Methods: Second-year respiratory therapy students were recruited from an advanced cardiovascular life support class. Participants conducted a 2-min trial of manually ventilating a test lung utilizing normal and decreased compliance settings with the flow-limiting device connected to an endotracheal tube. Demographic data on participants' age were collected. The control group consisted of a mechanical ventilator providing ventilation with the same test lung and compliance settings. Mean differences were compared between the manual ventilation and control group. Results: A total of 41 respiratory therapy students (71% female, 76% undergraduate) participated. The mean experience level using the bag-valve-mask was 6.71, and the mean confidence level was 8.02; the scale was 0-10 with high numbers indicating greater experience or confidence. A small but statistically significant difference was found in mean peak pressures between manual ventilation with the flow-limiting device (15 cm H₂O) and the mechanical ventilator (13 cm H₂O) for the normal lung setting (P = .008) but not for the decreased compliance lung setting (23 cm H₂O vs 23 cm H₂O with the ventilator). There was a significant difference in mean V_T between manual ventilation (412 mL) and the mechanical ventilator (460 mL) in the decreased compliance lung setting (P = .003) but not the normal compliance setting (452 mL vs 474 mL with the ventilator). Conclusions: Although there were some statistically significant differences between the 2 groups, these differences were not clinically important. Participants adequately manually ventilated with V_T similar to a mechanical ventilator.

Background: Pressure support ventilation is frequently associated with patient-ventilator asynchrony. Algorithms based on ventilator waveforms have been developed to automatically detect patient respiratory activity and to guide triggering and cycling. The aim of this study was to assess the performance in terms of synchronization of 6 mechanical ventilators, all provided with a waveform-guided software. Methods: This was a bench study to compare standard and new-generation systems simulating different respiratory mechanics, levels of assistance, and respiratory efforts. Six mechanical ventilators were tested: Hamilton G5 (G5) and C6 (C6), IMT bellavista1000 (B1000), Mindray SV300, and Philips RespironicsV200 (V200) and V60 (V60). Apart from V60, the other ventilators were tested twice: with default settings for standard triggering and cycling and with the waveform-guided automation. Results: With the automated settings, breaths with trigger delay ≤ 300 ms increased with B1000, G5, and C6. Ineffective efforts decreased with B1000, G5, C6, and V200. Improvement of triggering was mainly driven by findings obtained in the obstructive profile. With the automated settings, breaths with cycling delay > 300 ms decreased with B1000, G5, C6, and V200 while early cycled breaths increased with B1000. Improvement of cycling was mainly driven by findings obtained in the obstructive profile, whereas worsening of cycling was observed in the restrictive profile with 2 ventilators (B100 and V200). With the automated settings, the asynchrony index (AI) was reduced with G5 and C6 when all the profiles were grouped. In the obstructive profile, the AI decreased with B1000, G5, C6, and V200; in the restrictive profile, the AI increased with B1000. Conclusions: Waveforms-based algorithms have the potential to improve patient-ventilator synchronization. Automation had the most favorable impact when obstructive patients were simulated, while caution should be paid with restrictive ones.

Background: Molecular hydrogen (H₂) is a breathable gas that has been shown to have anti-oxidative, anti-inflammatory, and anti-apoptotic properties that may positively impact ischemia-reperfusion injury. The provision of 2% H₂ through unmodified mechanical ventilators may facilitate the clinical translation of H₂ as a therapeutic in critical illness. The effect of 2% H₂ on ventilator performance is unknown. Methods: Unmodified Maquet Servo-i, Maquet Servo-u, Dräger Evita Infinity V500, and Dräger Evita Babylog VN500 ventilators from clinical stock were tested in an experimental closed system using certified, premixed air and O₂ containing 2% H₂ gas. Wall air and O₂ supply were used as control. Ventilator settings were varied across the spectrum of neonatal to adult settings. End points included (1) difference between set and delivered tidal volume (V_T) (Douglas method), (2) difference between set versus delivered O₂ concentration, (3) delivered H₂ concentration (gas chromatography), and (4) ventilator pre-use check malfunction. Correlation between set and measured end points were quantified by linear regression analysis and bias by Bland-Altman analysis. Results: During H₂ administration, the average bias in measured versus set V_T was within ± 10% for all ventilators except for the Babylog VN500, which exhibited an average bias of -89.2% (95% CI -107.0 to -71.3). The average bias in measured F_IO2 was within ± 10% of set for all ventilators. Except for the Babylog VN500, all ventilators passed the pre-use check. Conclusions: Unmodified Servo-i, Servo-u, and Evita V500 ventilators deliver 2% H₂ mixtures with acceptable accuracy in V_T and F_IO2. The Babylog VN500, which uses hot-wire anometry and a higher set operating temperature, exhibits unacceptably inaccurate delivery of V_T with H₂ mixtures.

Background: Children were less affected by severe illness as compared to adults at the start of the COVID-19 pandemic. As the pandemic progressed and variants emerged, pediatric hospitalizations increased, and some previously healthy children developed multisystem inflammatory disorder. The aim of this study was to describe the characteristics and outcomes of children hospitalized with COVID-19 from the beginning of the pandemic through the Δ variant. Methods: Data were collected retrospectively for children hospitalized during March 2020-November 2021 with a diagnosis of COVID-19. Admissions were classified as early pandemic or during the delta variant, and outcomes were compared between the time periods. Primary outcome measures were hospital length of stay and use of respiratory support. The number of admissions/month was the secondary outcome. Results: There were 784 hospital admissions: 400 during early pandemic and 378 during the Δ period. Forty-four percent had an underlying medical condition, and 78% were not eligible for COVID-19 vaccination. Oxygen was the most common respiratory support modality and was required more often during Δ (P < .001). Hospital stay was longer during the Δ period (P < .001), and the number of monthly admissions was higher. A statistically significant but low correlation was identified between body mass index (BMI) Z score and stay (P < .001, r = 0.19). Conclusions: The Δ variant was associated with increased hospital length of stay and use of respiratory support compared to the early pandemic period. Children with preexisting medical conditions were more likely to require respiratory support and have longer hospitalization than others. Higher BMI Z score was also weakly associated with longer length of stay. The reason for admission was attributed to causes other than COVID-19 for the majority of admissions except during the Δ period.

Background: COPD is a heterogeneous disorder. We developed a multidisciplinary evaluation scheme to identify patients with COPD who may benefit from phenotype-specific therapy. Methods: Our team of general and interventional pulmonologists, thoracic surgeons, radiologists, respiratory therapists, and advanced practice nurses meets monthly to discuss patients with advanced COPD. For each patient, pulmonary function tests, imaging, and other pertinent data are reviewed. Emphysema is assessed visually and by quantitative computed tomography modalities. A consensus is sought for medical, bronchoscopic, and/or surgical treatments and recommendations are relayed to the referring physician. Results: The multidisciplinary team reviewed 510 cases between November 2015 and December 2022. Eighty five of 510 patients were found to be appropriate candidates for lung-volume-reduction surgery and 36 underwent the procedure. Patients in the post-multidisciplinary evaluation cohort experienced improvement in mean ± SD FEV₁ of 0.23 ± 0.38 L (P = .52) and mean ± SD reduction in residual volume by 0.78 ± 0.98 L (P = .085) 6 months after surgery, which was similar to the improvements in pre-multidisciplinary evaluation patients (P = .52 and P = .085, respectively). Of the 202 patients referred for bronchoscopic lung volume reduction, 28 patients underwent the procedure. Mean ± SD improvement in FEV₁ was 0.14 ± 0.18 L and mean ± SD reduction in residual volume was 0.68 ± 0.80 L (P = .002 and P = .001, respectively) at 6 months after the procedure. Most patients were not suitable candidates for lung volume reduction due to anatomical, physiologic, or phenotypical exclusions. Management was found to be optimal in the majority of patients who were not candidates for lung volume reduction (53.7%). A survey of meeting attendees indicated high confidence in managing these patients with a high likelihood of changing management decisions after multidisciplinary discussion. Conclusions: Most symptomatic advanced patients are not candidates for lung-volume-reduction interventions. There is an unmet need for novel therapeutic options in this population. The multidisciplinary evaluation consensus recommendations provide assurance and guidance to clinicians.

Background: COPD is a common diagnosis driving in-patient admissions. A major component of in-patient COPD management involves nebulized or inhaled bronchodilators. In many hospitals, the in-patient pharmacy limits medication availability and may auto-substitute short-acting nebulized bronchodilators (SANBs) for long-acting inhalers (LAIs) to cut costs; the effect of such policy change on patient care is unknown. Methods: We performed a retrospective, observational study at a quaternary teaching hospital to analyze respiratory therapy utilization in subjects with COPD on home LAI, who were admitted between December 1, 2022-February 28, 2023. We compared resource utilization between the following groups: SANB only, LAI + as-needed SANB, and LAI + scheduled SANB. Results: We reviewed 302 admissions. There were 97 in SANB group, 99 in LAI + as-needed SANB group, and 106 admissions in LAI + scheduled SANB group. Subjects in LAI + as-needed SANB category utilized significantly fewer treatments overall than SANB or LAI + scheduled SANB groups (1.6/d vs 4.2/d vs 4.5/d, respectively, P < .001) and suffered fewer missed treatments (0.2/d vs 1.7/d vs 1.3/d, respectively, P < .001). There was no significant difference in the length of stay between the 3 groups. Furthermore, overall costs were lowest in LAI + as-needed SANB compared to the SANB and LAI + scheduled SANB groups ($117.62/admission vs $219.71/admission vs $375.35/admission, respectively, P < .001). Within the SANB group, we found that only 36.1% of admissions included orders that complied with the auto-substitution policy. Conclusions: In conclusion, for patients with COPD on home LAI admitted to the hospital, substituting scheduled SANB for LAI resulted in higher costs, more frequent treatment utilization, and more missed doses than the alternative regimens. Moreover, most scheduled SANB orders were not reflective of the actual auto-substitution policy.