Comparison of trunk muscle exercises in supine position during short arm centrifugation with 1 g at centre of mass and upright in 1 g.

Spaceflight is associated with reduced antigravitational muscle activity, which results in trunk muscle atrophy and may contribute to post-flight postural and spinal instability. Exercise in artificial gravity (AG) performed via short-arm human centrifugation (SAHC) is a promising multi-organ countermeasure, especially to mitigate microgravity-induced postural muscle atrophy. Here, we compared trunk muscular activity (mm. rectus abdominis, ext. obliques and multifidi), cardiovascular response and tolerability of trunk muscle exercises performed during centrifugation with 1 g at individual center of mass on a SAHC against standard upright exercising. We recorded heart rate, blood pressure, surface trunk muscle activity, motion sickness and rating of perceived exertion (BORG) of 12 participants (8 male/4 female, 34 ± 7 years, 178.4 ± 8.2 cm, 72.1 ± 9.6 kg). Heart rate was significantly increased (p < 0.001) during exercises without differences in conditions. Systolic blood pressure was higher (p < 0.001) during centrifugation with a delayed rise during exercises in upright condition. Diastolic blood pressure was lower in upright (p = 0.018) compared to counter-clockwise but not to clockwise centrifugation. Target muscle activation were comparable between conditions, although activity of multifidi was lower (clockwise: p = 0.003, counter-clockwise: p < 0.001) and rectus abdominis were higher (clockwise: p = 0.0023, counter-clockwise: < 0.001) during centrifugation in one exercise type. No sessions were terminated, BORG scoring reflected a relevant training intensity and no significant increase in motion sickness was reported during centrifugation. Thus, exercising trunk muscles during centrifugation generates comparable targeted muscular and heart rate response and appears to be well tolerated. Differences in blood pressure were relatively minor and not indicative of haemodynamic challenge. SAHC-based muscle training is a candidate to reduce microgravity-induced inter-vertebral disc pathology and trunk muscle atrophy. However, further optimization is required prior to performance of a training study for individuals with trunk muscle atrophy/dysfunction.

Assessing the effects of artificial gravity in an analog of long-duration spaceflight: The protocol and implementation of the AGBRESA bed rest study.

A comprehensive strategy is required to mitigate risks to astronauts' health, well-being, and performance. This strategy includes developing countermeasures to prevent or reduce adverse responses to the stressors astronauts encounter during spaceflight, such as weightlessness. Because artificial gravity (AG) by centrifugation simultaneously affects all physiological systems, AG could mitigate the effects of weightlessness in multiple systems. In 2019, NASA and the German Aerospace Center conducted a 60-days Artificial Gravity Bed Rest Study with the European Space Agency (AGBRESA). The objectives of this study were to 1) determine if 30 min of AG daily is protective during head down bed rest, and 2) compare the protective effects of a single daily bout (30 min) of AG versus multiple daily bouts (6 × 5 min) of AG (1 Gz at the center of mass) on physiological functions that are affected by weightlessness and by head-down tilt bed rest. The AGBRESA study involved a comprehensive suite of standard and innovative technologies to characterize changes in a broad spectrum of physiological systems. The current article is intended to provide a detailed overview of the methods used during AGBRESA.

Gravity and Mastoid Effusion.

BACKGROUND: Asymptomatic mastoid effusions have recently been observed in astronauts returning from long-term spaceflight. In hospitalized patients, mastoid effusion increases the risks for bacterial otitis and mastoiditis. We reasoned that cephalad fluid shifts during strict -6° head down tilt bed rest could reproduce space-flight associated mastoid effusion and that artificial gravity may reverse the response. METHODS: The recent Artificial Gravity Bed Rest Study-European Space Agency study (AGBRESA) tested influences of artificial gravity during 60 days head down bed rest on a short-arm human centrifuge in healthy participants. The two intervention groups received daily artificial gravity with 30 minutes continuous artificial gravity or intermittent artificial gravity. A third group served as a control group and received no artificial gravity. We assessed cranial magnetic resonance images for mastoid effusions 1 day before bed rest, at days 14 and 52 of bed rest, and 3 days after bed rest. RESULTS: None of the participants exhibited mastoid effusions before bed rest. Six participants showed mastoid effusions at bed rest day 14 (4 continuous, 2 intermittent, 0 control). Fifteen participants showed mastoid effusions at bed rest day 52 and 3 days after bed rest (7 continuous, 3 intermittent, 5 control). CONCLUSIONS: Mastoid effusions commonly occur during strict head down tilt bed rest. The model can be applied to study the mechanisms and potential countermeasures for space flight-associated mastoid effusions. Formation of mastoid effusions during head down tilt bed rest is not prevented by daily 30 minutes short-arm intermittent or continuous centrifugation.

Association of Communication Interventions to Discuss Code Status With Patient Decisions for Do-Not-Resuscitate Orders: A Systematic Review and Meta-analysis.

Importance: Whether specific communication interventions to discuss code status alter patient decisions regarding do-not-resuscitate code status and knowledge about cardiopulmonary resuscitation (CPR) remains unclear. Objective: To conduct a systematic review and meta-analysis regarding the association of communication interventions with patient decisions and knowledge about CPR. Data Sources: PubMed, Embase, PsycINFO, and CINAHL were systematically searched from the inception of each database to November 19, 2018. Study Selection: Randomized clinical trials focusing on interventions to facilitate code status discussions. Two independent reviewers performed the data extraction and assessed risk of bias using the Cochrane Risk of Bias Tool. Data were pooled using a fixed-effects model, and risk ratios (RRs) with corresponding 95% CIs are reported. Data Extraction and Synthesis: The study was performed according to the PRISMA guidelines. Main Outcomes and Measures: The primary outcome was patient preference for CPR, and the key secondary outcome was patient knowledge regarding life-sustaining treatment. Results: Fifteen randomized clinical trials (2405 patients) were included in the qualitative synthesis, 11 trials (1463 patients) were included for the quantitative synthesis of the primary end point, and 5 trials (652 patients) were included for the secondary end point. Communication interventions were significantly associated with a lower preference for CPR (390 of 727 [53.6%] vs 284 of 736 [38.6%]; RR, 0.70; 95% CI, 0.63-0.78). In a preplanned subgroup analysis, studies using resuscitation videos as decision aids compared with other interventions showed a stronger decrease in preference for life-sustaining treatment (RR, 0.56; 95% CI, 0.48-0.64 vs 1.03; 95% CI, 0.87-1.22; between-group heterogeneity P < .001). Also, a significant association was found between communication interventions and better patient knowledge (standardized mean difference, 0.55; 95% CI, 0.39-0.71). Conclusions and Relevance: Communication interventions are associated with patient decisions regarding do-not-resuscitate code status and better patient knowledge and may thus improve code status discussions.

A preoperative single dose of methadone for moderate-to-severely painful surgery reduces postoperative morphine consumption.

BACKGROUND: Data from patient questionnaires reveal that the intensity of postoperative pain is widely underestimated. Insufficient pain control may contribute to impaired short- and long-term outcome. Preoperative administration of methadone might potentially improve postoperative pain control due to its long pharmacological half-life. METHODS: The aim of this study was to evaluate the effect of a single dose of methadone administered at anesthesia induction on postoperative analgesic requirements in ASA I-III patients after moderate-to-severely painful surgery scheduled for ≥90 minutes. Patients were randomized to receive either a single dose of methadone (0.2 mg/kg) or fentanyl (standard, 0.003 mg/kg) intravenously (IV) at anesthesia induction. For postoperative pain control, all study patients were accommodated with morphine on the basis of patient-controlled analgesia (PCA). RESULTS: Per-protocol analysis revealed that the median cumulative morphine consumption was significantly lower in patients receiving a single dose of methadone, in the Postanesthesia Care Unit (0 mg vs. 7 mg of morphine, P<0.01) and during the first 72 hours after surgery (19 mg vs. 35 mg of morphine, P<0.05 for all days). Fentanyl consumption during surgery (0.25 mg [0.1-0.425 mg] in the study group vs. 0.3 mg [0.15-0.45 mg] in the control group, P=0.4499) was comparable among groups. Median pain scores at rest and in motion, and patient satisfaction were also similar in both groups (95.7% vs. 89.3% of patients were satisfied in the study and control group, respectively) during follow-up on postoperative days 1-3. CONCLUSIONS: A single dose of methadone administered at anesthesia induction prior to moderate-to-severely painful surgery is a possible strategy to reduce postoperative morphine consumption.

The frequent and underrecognised co-occurrence of acute exacerbated COPD and depression warrants screening: a systematic review.

Patients with acute exacerbated chronic obstructive pulmonary disease (AECOPD) and concurrent depression suffer significant psychological stress and decreased quality of life. The aim of this study was to collate data, guidelines and recommendations from publications on the screening and management of depressive mood disorders in patients hospitalised with AECOPD.We systematically searched four databases for publications reporting screening or management of depression in patients hospitalised for AECOPD. The identification of articles was based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement.Out of 1494 original articles screened, 35 met all inclusion criteria. These report a prevalence of depression in AECOPD ranging between 9.5% and 85.6%. Some studies report high postadmission mortality rates for depressive AECOPD patients, and higher readmission rates in depressive versus nondepressive AECOPD patients. Importantly, none of the 35 publications included suggestions on the screening and management of depression in AECOPD.Depression and AECOPD frequently co-occur, and this worsens outcomes. Yet we did not find recommendations on management, and few interventional studies. Patients hospitalised with AECOPD should be systematically screened for depression and treatment recommendations should be developed for these patients. Randomised studies on how to screen and treat depression in hospitalised AECOPD are necessary.