Persistence of inflammatory and vascular mediators 5 months after hospitalization with COVID-19 infection.

Background and aim: In acute severe COVID-19, patients present with lung inflammation and vascular injury, accompanied by an exaggerated cytokine response. In this study, our aim was to describe the inflammatory and vascular mediator profiles in patients who were previously hospitalized with COVID-19 pneumonitis, months after their recovery, and compare them with those in patients recovering from severe sepsis and in healthy controls. Methods: A total of 27 different cytokine, chemokine, vascular endothelial injury and angiogenic mediators were measured in the plasma of forty-nine patients 5.0 ± 1.9 (mean ± SD) months after they were hospitalized with COVID-19 pneumonia, eleven patients 5.4 ± 2.9 months after hospitalization with acute severe sepsis, and 18 healthy controls. Results: Compared with healthy controls, IL-6, TNFα, SAA, CRP, Tie-2, Flt1, and PIGF were significantly increased in the post-COVID group, and IL-7 and bFGF were significantly reduced. While IL-6, PIGF, and CRP were also significantly elevated in post-Sepsis patients compared to controls, the observed differences in TNFα, Tie-2, Flt-1, IL-7 and bFGF were unique to the post-COVID group. TNFα levels significantly correlated with the severity of acute COVID-19 illness (spearman's r = 0.30, p < 0.05). Furthermore, in post-COVID patients, IL-6 and CRP were each strongly negatively correlated with gas transfer factor %predicted (spearman's r = -0.51 and r = -0.57, respectively, p < 0.002) and positively correlated with computed tomography (CT) abnormality scores at recovery (r = 0.28 and r = 0.46, p < 0.05, respectively). Conclusion: A unique inflammatory and vascular endothelial damage mediator signature is found in plasma months following acute COVID-19 infection. Further research is required to determine its pathophysiological and clinical significance.

Altered lung physiology in two cohorts after COVID-19 infection as assessed by computed cardiopulmonography.

The longer-term effects of COVID-19 on lung physiology remain poorly understood. Here, a new technique, computed cardiopulmonography (CCP), was used to study two COVID-19 cohorts (MCOVID and C-MORE-LP) at both ∼6 and ∼12 mo after infection. CCP is comprised of two components. The first is collection of highly precise, highly time-resolved measurements of gas exchange with a purpose-built molecular flow sensor based around laser absorption spectroscopy. The second component is estimation of physiological parameters by fitting a cardiopulmonary model to the data set. The measurement protocol involved 7 min of breathing air followed by 5 min of breathing pure O2. One hundred seventy-eight participants were studied, with 97 returning for a repeat assessment. One hundred twenty-six arterial blood gas samples were drawn from MCOVID participants. For participants who had required intensive care and/or invasive mechanical ventilation, there was a significant increase in anatomical dead space of ∼30 mL and a significant increase in alveolar-to-arterial Po2 gradient of ∼0.9 kPa relative to control participants. Those who had been hospitalized had reductions in functional residual capacity of ∼15%. Irrespectively of COVID-19 severity, participants who had had COVID-19 demonstrated a modest increase in ventilation inhomogeneity, broadly equivalent to that associated with 15 yr of aging. This study illustrates the capability of CCP to study aspects of lung function not so easily addressed through standard clinical lung function tests. However, without measurements before infection, it is not possible to conclude whether the findings relate to the effects of COVID-19 or whether they constitute risk factors for more serious disease.NEW & NOTEWORTHY This study used a novel technique, computed cardiopulmonography, to study the lungs of patients who have had COVID-19. Depending on severity of infection, there were increases in anatomical dead space, reductions in absolute lung volumes, and increases in ventilation inhomogeneity broadly equivalent to those associated with 15 yr of aging. However, without measurements taken before infection, it is unclear whether the changes result from COVID-19 infection or are risk factors for more severe disease.

Early mobilization of mechanically ventilated ICU patients in Saudi Arabia: Results of an ICU-wide national survey.

BACKGROUND: Improved outcomes for patients on mechanical ventilation may be achieved with early mobilization (EM). However, it is not clear how widely this strategy is adopted into routine intensive care unit (ICU) practice in Saudi Arabia. OBJECTIVES: This study was conducted to describe the present practices and challenges to providing EM for mechanically ventilated patients, which may drive dissemination and implementation activities. METHODS: We approached 205 ICUs across Saudi Arabia using a validated tool to assess ICU characteristics, the practices of EM for mechanically ventilated patients, and the barriers to providing EM. RESULTS: We approached 205 ICU persons in charge and achieved a 65% response rate (133 ICUs). The prevalence of EM for mechanically ventilated patients was 47% (63 ICUs). A total of 85 (64%) of the respondents reported having no previous training in EM. The absence of a written protocol was reported by 55% of the ICU practitioners in charge, 36% started EM within 2 to 5 days of critical illness, and 35% reported that performing EM for mechanically ventilated patients was totally dependent on physicians' orders. Forty-seven percent of the ICUs that practised EM had at least one coordinator or person in charge of facilitating EM. The highest level of EM with mechanically ventilated patients was 35/63 (55%) with patients remaining in-bed and 28/63 (45%) with patient getting out of bed. A majority of the respondents (39, 64%) performed EM once daily for an interval period of more than 15 min. Previous training in EM and years of experience of the ICU person in charge were significant factors that promoted EM for mechanically ventilated ICU patients (OR: 7.6 (3.37-17.26); p < 0.001 and OR: 1.07 (1.01-1.14), p = 0.004, respectively). Existing protocols increased the odds of starting EM within 2 to 5 days of critical illness by six-fold (OR: 6.03 (1.79-20.30); p = 0.004). No written guidelines/protocols available for EM, medical instability, and limited staff were the most common hospital-, patient- and health care provider-related barriers to EM in the ICUs, respectively. CONCLUSION: The prevalence of EM for mechanically ventilated patients across Saudi Arabia was 47%, although only 36% of the ICU staff had previous training in EM. Targeting modifiable barriers to EM, including a lack of training, guidelines and protocols, and staffing, will help to promote EM in Saudi Arabian ICUs.

Patient-Ventilator Asynchrony in Critical Care Settings: National Outcomes of Ventilator Waveform Analysis.

BACKGROUND: Patient-ventilator asynchrony (PVA) is a prevalent and often underrecognized problem in mechanically ventilated patients. Ventilator waveform analysis is a noninvasive and reliable means of detecting PVAs, but the use of this tool has not been broadly studied. METHODS: Our observational analysis leveraged a validated evaluation tool to assess the ability of critical care practitioners (CCPs) to detect different PVA types as presented in three videos. This tool consisted of three videos of common PVAs (i.e., double-triggering, auto-triggering, and ineffective triggering). Data were collected via an evaluation sheet distributed to 39 hospitals among the various CCPs, including respiratory therapists (RTs), nurses, and physicians. RESULTS: A total of 411 CCPs were assessed; of these, only 41 (10.2%) correctly identified the three PVA types, while 92 (22.4%) correctly detected two types and 174 (42.3%) correctly detected one; 25.3% did not recognize any PVA. There were statistically significant differences between trained and untrained CCPs in terms of recognition (three PVAs, p < 0.001; two PVAs, p = 0.001). The majority of CCPs who identified one or zero PVAs were untrained, and such differences among groups were statistically significant (one PVA, p = 0.001; zero PVAs, p = 0.004). Female gender and prior training on ventilator waveforms were found to increase the odds of identifying more than two PVAs correctly, with odds ratios (ORs) (95% confidence intervals [CIs]) of 1.93 (1.07-3.49) and 5.41 (3.26-8.98), respectively. Profession, experience, and hospital characteristics were not found to correlate with increased odds of detecting PVAs; this association generally held after applying a regression model on the RT profession, with the ORs (95% CIs) of prior training (2.89 [1.28-6.51]) and female gender (2.49 [1.15-5.39]) showing the increased odds of detecting two or more PVAs. CONCLUSION: Common PVAs detection were found low in critical care settings, with about 25% of PVA going undetected by CCPs. Female gender and prior training on ventilator graphics were the only significant predictive factors among CCPs and RTs in correctly identifying PVAs. There is an urgent need to establish teaching and training programs, policies, and guidelines vis-à-vis the early detection and management of PVAs in mechanically ventilated patients, so as to improve their outcomes.