Assessment of functional capacity before major non-cardiac surgery: an international, prospective cohort study.

BACKGROUND: Functional capacity is an important component of risk assessment for major surgery. Doctors' clinical subjective assessment of patients' functional capacity has uncertain accuracy. We did a study to compare preoperative subjective assessment with alternative markers of fitness (cardiopulmonary exercise testing [CPET], scores on the Duke Activity Status Index [DASI] questionnaire, and serum N-terminal pro-B-type natriuretic peptide [NT pro-BNP] concentrations) for predicting death or complications after major elective non-cardiac surgery. METHODS: We did a multicentre, international, prospective cohort study at 25 hospitals: five in Canada, seven in the UK, ten in Australia, and three in New Zealand. We recruited adults aged at least 40 years who were scheduled for major non-cardiac surgery and deemed to have one or more risk factors for cardiac complications (eg, a history of heart failure, stroke, or diabetes) or coronary artery disease. Functional capacity was subjectively assessed in units of metabolic equivalents of tasks by the responsible anaesthesiologists in the preoperative assessment clinic, graded as poor (<4), moderate (4-10), or good (>10). All participants also completed the DASI questionnaire, underwent CPET to measure peak oxygen consumption, and had blood tests for measurement of NT pro-BNP concentrations. After surgery, patients had daily electrocardiograms and blood tests to measure troponin and creatinine concentrations until the third postoperative day or hospital discharge. The primary outcome was death or myocardial infarction within 30 days after surgery, assessed in all participants who underwent both CPET and surgery. Prognostic accuracy was assessed using logistic regression, receiver-operating-characteristic curves, and net risk reclassification. FINDINGS: Between March 1, 2013, and March 25, 2016, we included 1401 patients in the study. 28 (2%) of 1401 patients died or had a myocardial infarction within 30 days of surgery. Subjective assessment had 19·2% sensitivity (95% CI 14·2-25) and 94·7% specificity (93·2-95·9) for identifying the inability to attain four metabolic equivalents during CPET. Only DASI scores were associated with predicting the primary outcome (adjusted odds ratio 0·96, 95% CI 0·83-0·99; p=0·03). INTERPRETATION: Subjectively assessed functional capacity should not be used for preoperative risk evaluation. Clinicians could instead consider a measure such as DASI for cardiac risk assessment. FUNDING: Canadian Institutes of Health Research, Heart and Stroke Foundation of Canada, Ontario Ministry of Health and Long-Term Care, Ontario Ministry of Research, Innovation and Science, UK National Institute of Academic Anaesthesia, UK Clinical Research Collaboration, Australian and New Zealand College of Anaesthetists, and Monash University.

Osteopontin lung gene expression is a marker of disease severity in pulmonary arterial hypertension.

BACKGROUND AND OBJECTIVE: Osteopontin (OPN) is a pleiotropic cytokine involved in the proliferation of pulmonary artery smooth muscle cells (PA-SMC). OPN is upregulated in the lungs of patients with pulmonary hypertension (PH) associated with pulmonary fibrosis, suggesting that the lung is a source of OPN. We hypothesized that OPN lung expression is elevated in Group I pulmonary arterial hypertension (PAH) and is correlated to haemodynamics. METHODS: Microarray analysis (Affymetrix) was performed after RNA was extracted from explanted lungs in 15 patients with Group I PAH who underwent lung transplantation (LTx) and 11 normal controls. PA pressure levels were recorded intraoperatively, immediately before starting LTx. Serum OPN levels were measured in subjects with PAH, Group II PH and normal controls on the day of right heart catheterization. RESULTS: OPN was among the top five upregulated genes in PAH compared to normal controls, which was confirmed by reverse transcription polymerase chain reaction (RT-PCR). OPN expression was similar and equally elevated in different subtypes of PAH. A strong significant correlation was observed between mean pulmonary arterial pressure and OPN gene expression. Ingenuity pathway analysis showed the involvement of OPN in functions and networks relevant to angiogenesis, cell death and proliferation of PA-SMC. OPN serum levels did not differ in subjects with Group I PAH and Group II PH. CONCLUSION: In the lungs of patients with severe PAH, OPN is highly expressed and the level of expression is significantly correlated to disease severity. OPN may play an important role in the vascular remodelling process of PAH.

The relationship of pulmonary vascular resistance and compliance to pulmonary artery wedge pressure during submaximal exercise in healthy older adults.

KEY POINTS: A consistent inverse hyperbolic relationship has been observed between pulmonary vascular resistance and compliance, although changes in pulmonary artery wedge pressure (PAWP) may modify this relationship. This relationship predicts that pulmonary artery systolic, diastolic and mean pressure maintain a consistent relationship relative to the PAWP. We show that, in healthy exercising human adults, both pulmonary vascular resistance and compliance decrease in relation to exercise-associated increases in PAWP. Pulmonary artery systolic, diastolic and mean pressures maintain a consistent relationship with one another, increasing linearly with increasing PAWP. Increases in PAWP in the setting of exercise are directly related to a decrease in pulmonary vascular compliance, despite small decreases in pulmonary vascular resistance, thereby increasing the pulsatile afterload to the right ventricle. ABSTRACT: The resistive and pulsatile components of right ventricular afterload (pulmonary vascular resistance, Rp; compliance, Cp) are related by an inverse hyperbolic function, expressed as their product known as RpCp-time. The RpCp-time exhibits a narrow range, although it may be altered by the pulmonary artery wedge pressure (PAWP). Identifying the determinants of RpCp-time should improve our understanding of the physiological behaviour of pulmonary arterial systolic (PASP), diastolic (PADP) and mean (mPAP) pressures in response to perturbations. We examined the effect of exercise in 28 healthy non-athletic adults (55 ± 6 years) who underwent right heart catheterization to assess haemodynamics and calculate Rp and Cp. Measurements were made at rest and during two consecutive 8-10 min stages of cycle ergometry, at targeted heart-rates of 100 beats min(-1) (Light) and 120 beats min(-1) (Moderate). Cardiac output increased progressively during exercise. PASP, PADP, mPAP and PAWP increased for Light exercise, without any further rise for Moderate exercise. RpCp-time decreased for Light exercise (0.39 ± 0.08 to 0.25 ± 0.08, P < 0.001) without any further change for Moderate exercise, and the decrease in RpCp-time was related to changes in PAWP (r(2)  = 0.26, P < 0.001). Changes in PASP (r(2)  = 0.43, P < 0.001), PADP (r(2)  = 0.47, P < 0.001) and mPAP (r(2)  = 0.50, P < 0.001) were linearly correlated with changes in PAWP, although they were not significantly related to changes in cardiac output. In healthy adults, exercise is associated with decreases in Cp and a resultant decline in RpCp-time, indicating increased pulsatile right ventricular afterload. Changes in RpCp-time, PASP, PADP and mPAP were systematically related to increases in PAWP.

High-frequency oscillation in early acute respiratory distress syndrome.

BACKGROUND: Previous trials suggesting that high-frequency oscillatory ventilation (HFOV) reduced mortality among adults with the acute respiratory distress syndrome (ARDS) were limited by the use of outdated comparator ventilation strategies and small sample sizes. METHODS: In a multicenter, randomized, controlled trial conducted at 39 intensive care units in five countries, we randomly assigned adults with new-onset, moderate-to-severe ARDS to HFOV targeting lung recruitment or to a control ventilation strategy targeting lung recruitment with the use of low tidal volumes and high positive end-expiratory pressure. The primary outcome was the rate of in-hospital death from any cause. RESULTS: On the recommendation of the data monitoring committee, we stopped the trial after 548 of a planned 1200 patients had undergone randomization. The two study groups were well matched at baseline. The HFOV group underwent HFOV for a median of 3 days (interquartile range, 2 to 8); in addition, 34 of 273 patients (12%) in the control group received HFOV for refractory hypoxemia. In-hospital mortality was 47% in the HFOV group, as compared with 35% in the control group (relative risk of death with HFOV, 1.33; 95% confidence interval, 1.09 to 1.64; P=0.005). This finding was independent of baseline abnormalities in oxygenation or respiratory compliance. Patients in the HFOV group received higher doses of midazolam than did patients in the control group (199 mg per day [interquartile range, 100 to 382] vs. 141 mg per day [interquartile range, 68 to 240], P<0.001), and more patients in the HFOV group than in the control group received neuromuscular blockers (83% vs. 68%, P<0.001). In addition, more patients in the HFOV group received vasoactive drugs (91% vs. 84%, P=0.01) and received them for a longer period than did patients in the control group (5 days vs. 3 days, P=0.01). CONCLUSIONS: In adults with moderate-to-severe ARDS, early application of HFOV, as compared with a ventilation strategy of low tidal volume and high positive end-expiratory pressure, does not reduce, and may increase, in-hospital mortality. (Funded by the Canadian Institutes of Health Research; Current Controlled Trials numbers, ISRCTN42992782 and ISRCTN87124254, and ClinicalTrials.gov numbers, NCT00474656 and NCT01506401.).

Survival in rheumatoid arthritis-associated pulmonary arterial hypertension compared with idiopathic pulmonary arterial hypertension.

BACKGROUND AND OBJECTIVE: In this study, we evaluated survival in rheumatoid arthritis-associated pulmonary arterial hypertension (RA-PAH) compared with idiopathic pulmonary arterial hypertension (IPAH) patients, and evaluate differences in disease severity and treatment. METHODS: We conducted a retrospective cohort study of RA-PAH and IPAH at the University Health Network Pulmonary Hypertension Programme, Toronto, Canada. The primary outcome was time to all-cause mortality. We evaluated survival using Kaplan-Meier curves. Using a propensity score-matched cohort, we used Cox proportional hazards models to estimate survival. RESULTS: Screening 1385 patients identified 18 RA-PAH and 155 IPAH patients. RA-PAH patients had an older median age of onset (64.0 vs 53.7 years) and lower baseline mean pulmonary arterial pressure (mPAP) (41 vs 50 mm Hg, P = 0.02). RA-PAH patients tended to have a higher proportion of females (83% vs 70%, relative risk 0.55, 95% confidence interval (CI): 0.19-1.57), lower proportion with baseline World Health Organization functional class III/IV (39% vs 52%), lower median baseline brain natriuretic peptide (58.4 vs 95.0 pg/mL) and longer baseline 6-min walk distance (440 vs 397 m). There were 35 deaths, 2/18 (11%) RA-PAH patients and 33/155 (21%) IPAH patients. The unadjusted 1-year survival was 93% for RA-PAH and 94% for IPAH. In the matched cohort, there were seven deaths: 2/18 (11%) RA-PAH and 5/18 (28%) IPAH patients, hazard ratio 1.53 (95% CI: 0.15-2.84). Separation of survival curves did not achieve statistical significance, log-rank 0.56. CONCLUSIONS: Compared with IPAH patients, RA-PAH patients have an older age of onset and lower baseline mPAP. RA-PAH patients have comparable survival to IPAH patients.

Oxygenation response to positive end-expiratory pressure predicts mortality in acute respiratory distress syndrome. A secondary analysis of the LOVS and ExPress trials.

RATIONALE: Previous trials of higher positive end-expiratory pressure (PEEP) for acute respiratory distress syndrome (ARDS) failed to demonstrate mortality benefit, possibly because of differences in lung recruitability among patients with ARDS. OBJECTIVES: To determine whether the physiological response to increased PEEP is associated with mortality. METHODS: In a secondary analysis of the Lung Open Ventilation Study (LOVS, n = 983), we examined the relationship between the initial response to changes in PEEP after randomization and mortality. We sought to corroborate our findings using data from a different trial of higher PEEP (ExPress, n = 749). MEASUREMENTS AND MAIN RESULTS: The oxygenation response (change in ratio of arterial partial pressure of oxygen to fraction of inspired oxygen: P/F) after the initial change in PEEP after randomization varied widely (median, 9.5 mm Hg; interquartile range, -16 to 47) and was only weakly related to baseline P/F or the magnitude of PEEP change. Among patients in whom PEEP was increased after randomization, an increase in P/F was associated with reduced mortality (multivariable logistic regression; adjusted odds ratio, 0.80 [95% confidence interval, 0.72-0.89] per 25-mm Hg increase in P/F), particularly in patients with severe disease (baseline P/F [less-than-or-equal-to] 150 mm Hg). Changes in compliance and dead space were not associated with mortality. These findings were confirmed by a similar analysis of data from the ExPress trial. CONCLUSIONS: Patients with ARDS who respond to increased PEEP by improved oxygenation have a lower risk of death. The oxygenation response to PEEP might be used to predict whether patients will benefit from higher versus lower PEEP.

Dysphagia and associated risk factors following extubation in cardiovascular surgical patients.

Following cardiovascular (CV) surgery, prolonged mechanical ventilation of >48 h increases dysphagia frequency over tenfold: 51 % compared to 3-4 % across all durations. Our primary objective was to identify dysphagia frequency following CV surgery with respect to intubation duration. Our secondary objective was to explore characteristics associated with dysphagia across the entire sample. Using a retrospective design, we stratified all consecutive patients who underwent CV surgery in 2009 at our institution into intubation duration groups defined a priori: I (≤ 12 h), II (>12 to ≤ 24 h), III (>24 to ≤ 48 h), and IV (>48 h). Eligible patients were >18 years old who survived extubation following coronary artery bypass alone or cardiac valve surgery. Patients who underwent tracheotomy were excluded. Pre-, peri-, and postoperative patient variables were extracted from a pre-existing database and medical charts by two blinded reviewers. Disagreements were resolved by consensus. Across the entire sample, multivariable logistic regression analysis determined independent predictors of dysphagia. Across the entire sample, dysphagia frequency was 5.6 % (51/909) but varied by group: I, 1 % (7/699); II, 8.2 % (11/134); III, 16.7 % (6/36); and IV, 67.5 % (27/40). Across the entire sample, the independent predictors of dysphagia included intubation duration in 12-h increments (p < 0.001; odds ratio [OR] 1.93, 95 % confidence interval [CI] 1.63-2.29) and age in 10-year increments (p = 0.004; OR 2.12, 95 % CI 1.27-3.52). Patients had a twofold increase in their odds of developing dysphagia for every additional 12 h with endotracheal intubation and for every additional decade in age. These patients should undergo post-extubation swallow assessments to minimize complications.

Left atrial reservoir pressure-volume relations during exercise in healthy older adults.

The left atrium (LA) mediates cardiopulmonary interactions. During ventricular systole, the LA functions as a compliant reservoir that is coupled to the left ventricle (LV) and offloads volume from the pulmonary vasculature. We aimed to describe LA reservoir function using phasic relationships between pulmonary artery wedge pressure (PAWP) and LA volume events. We included healthy adults (7 M/6 F, 56 ± 8 yr) who were studied at rest and during semirecumbent cycle ergometry at a target of 100 beats/min heart rate. Right heart catheterization was performed to record the PAWP and two-dimensional (2-D) echocardiography was used to measure LA and LV volumes. We manually measured A-wave, x-trough, V-wave, and y-trough PAWP beat-by-beat, as well as minimal, maximal, and precontraction biplane LA volumes. Heart rate increased by 40 ± 7 beats/min with exercise; stroke volume and cardiac output also rose. Although all phasic PAWP measurements increased with exercise, the x-V pressure pulse during LA filling doubled from 4 ± 2 to 8 ± 4 mmHg (P = 0.001). LA minimal volume was unchanged but maximal volume increased from 39 ± 9 to 48 ± 9 mL (P < 0.001) with exercise, and so reservoir volume increased from 24 ± 5 to 32 ± 8 mL (P < 0.001). As such, calculated LA compliance decreased from 6.8 ± 3.4 to 4.8 ± 2.6 mL/mmHg (P = 0.029). The product of V-wave PAWP and LA maximal volume, a surrogate for LA wall stress, increased from 486 ± 193 to 953 ± 457 mmHg·mL (P < 0.001). In healthy older adults during submaximal exercise, the PAWP waveform shifts upward and its amplitude widens, LA filling increases, LA compliance decreases modestly, and LA wall stress may augment substantially.NEW & NOTEWORTHY We combined invasive estimates of left atrial pressure with noninvasive left atrial volume measurements made at rest and during exercise in healthy humans. Left atrial pressure and volume both increased with exercise, though the pressure increase was relatively greater, and calculated compliance decreased modestly while estimated peak wall stress nearly doubled. Our results demonstrate left atrial loading during exercise in healthy older adults and provide insight into how the left atrium mediates cardiopulmonary interactions.

Exercise and pulsatile pulmonary vascular loading in chronic thromboembolic pulmonary disease.

Chronic thromboembolic pulmonary disease (CTEPD) is characterized by organized nonresolving thrombi in pulmonary arteries (PA). In CTEPD with pulmonary hypertension (PH), chronic thromboembolic PH (CTEPH), early wave reflection results in abnormalities of pulsatile afterload and augmented PA pressures. We hypothesized that exercise during right heart catheterization (RHC) would elicit more frequent elevations of pulsatile vascular afterload than resistive elevations in patients with CTEPD without PH. The interdependent physiology of pulmonary venous and PA hemodynamics was also evaluated. Consecutive patients with CTEPD without PH (resting mean PA pressure ≤20 mmHg) undergoing an exercise RHC were identified. Latent resistive and pulsatile abnormalities of pulmonary vascular afterload were defined as an exercise mean PA pressure/cardiac output >3 WU, and PA pulse pressure to PA wedge pressure (PA PP/PAWP) ratio >2.5, respectively. Forty-five patients (29% female, 53 ± 14 years) with CTEPD without PH were analyzed. With exercise, 19 patients had no abnormalities (ExNOR), 26 patients had abnormalities (ExABN) of pulsatile (20), resistive (2), or both (4) elements of pulmonary vascular afterload. Exercise elicited elevations of pulsatile afterload (53%) more commonly than resistive afterload (13%) (p < 0.001). ExABN patients had lower PA compliance and higher pulmonary vascular resistance at rest and exercise and prolonged resistance-compliance time product at rest. The physiological relationship between changes in PA pressures relative to PAWP was disrupted in the ExABN group. In CTEPD without PH, exercise RHC revealed latent pulmonary vascular afterload elevations in 58% of patients with more frequent augmentation of pulsatile than resistive pulmonary vascular afterload.

Alterations of pulmonary vascular afterload in exercise-induced pre- and post-capillary pulmonary hypertension.

Exercise imposes increased pulmonary vascular afterload based on rises in pulmonary artery (PA) wedge pressure, declines in PA compliance, and resistance-compliance time. In health, afterload stress stabilizes during steady-state exercise. Our objective was to examine alterations of these exercise-associated stresses in states of pre- and post-capillary pulmonary hypertension (PH). PA hemodynamics were evaluated at rest, 2 and 7 min of steady-state exercise at moderate intensity in patients who exhibited Pre-capillary (n = 22) and post-capillary PH (n = 22). Patients with normal exercise hemodynamics (NOR-HD) (n = 32) were also studied. During exercise in all groups, PA wedge pressure increased at 2 min, with no further change at 7 min. In post-capillary PH and NOR-HD, increases in PA diastolic pressure and diastolic pressure gradient remained stable at 2 and 7 min of exercise, while in pre-capillary PH, both continued to increase at 7 min. The behavior of the diastolic pressure gradient was linearly related to the duration of resistance-compliance time at rest (r2  = 0.843) and exercise (r2  = 0.760). Exercise resistance-compliance time was longer in pre-capillary PH associated with larger increases in diastolic pressure gradient. Conversely, resistance-compliance time was shortest in post-capillary PH compared to pre-capillary PH and NOR-HD and associated with limited increases in exercise diastolic pressure gradient. During steady-state, modest-intensity exercise-specific patterns of pulmonary vascular afterload responses were observed in pre- and post-capillary PH relative to NOR-HD. Longer resistance-compliance time related to greater increases in PA diastolic pressure and diastolic pressure gradients in pre-capillary PH, while shorter resistance-compliance time appeared to limit these increases in post-capillary PH.

Unlocking the potential of RNA-based therapeutics in the lung: current status and future directions.

Awareness of RNA-based therapies has increased after the widespread adoption of mRNA vaccines against SARS-CoV-2 during the COVID-19 pandemic. These mRNA vaccines had a significant impact on reducing lung disease and mortality. They highlighted the potential for rapid development of RNA-based therapies and advances in nanoparticle delivery systems. Along with the rapid advancement in RNA biology, including the description of noncoding RNAs as major products of the genome, this success presents an opportunity to highlight the potential of RNA as a therapeutic modality. Here, we review the expanding compendium of RNA-based therapies, their mechanisms of action and examples of application in the lung. The airways provide a convenient conduit for drug delivery to the lungs with decreased systemic exposure. This review will also describe other delivery methods, including local delivery to the pleura and delivery vehicles that can target the lung after systemic administration, each providing access options that are advantageous for a specific application. We present clinical trials of RNA-based therapy in lung disease and potential areas for future directions. This review aims to provide an overview that will bring together researchers and clinicians to advance this burgeoning field.

Using standardized family members to teach communication skills and ethical principles to critical care trainees.

OBJECTIVE: We sought to determine the effectiveness of standardized family members for improving communication skills and ethical and legal knowledge of senior intensive care unit trainees. DESIGN: Multimodal evaluation of mixed-methods educational intervention. SETTING: Postgraduate critical care medicine academic program. SUBJECTS: Postgraduate subspecialty critical care medicine trainees. INTERVENTION: Communication workshop featuring a short didactic session and four simulated family meetings using trained professionals as standardized family members. MEASUREMENTS: Ethical and legal knowledge and comfort with communication (before and after the workshop) and communication skill (during the workshop). MAIN RESULTS: Fifty-one postgraduate critical care medicine subspecialty trainees participated in the workshop over a 5-yr period. Ethical and legal knowledge and comfort scores improved significantly among trainees who participated in the workshop. Ninety percent of trainees felt that the workshop had met or exceeded their expectations and would recommend it to other trainees. Ninety-eight percent of trainees felt that the workshop had met the highest priority learning objectives they identified. Communication scores showed a trend towards improvement over the course of the workshop, although the improvements were not significant. Participants reflecting on the workshop >1 yr later overwhelmingly felt that it had prepared them for real communication challenges in training and practice. CONCLUSIONS: This workshop was effective for improving ethical and legal knowledge and comfort with communication among critical care medicine trainees. Participants overwhelmingly felt that it had met their learning needs and that it was an effective teaching tool that had prepared them for real communication challenges in training and practice. It could be used in a variety of contexts to address an often-neglected area of education.

The effect of endogenous estrogen on Doppler-estimated right ventricular systolic pressure during exercise.

We evaluated the effect of endogenous estrogen levels on exercise-related changes in right ventricular systolic pressure (RVSP) of healthy, eumenorrheic, sedentary women. Volunteers were studied at two separates phases of the menstrual cycle (LO and HI estrogen phases), exercised on a semi-supine ergometer with escalating workload and monitored continuously by 12-lead ECG and automated blood pressure cuff. At each exercise stage, Doppler echocardiography measurements were obtained and analyzed to determine RVSP. Fourteen subjects (age 24 ± 5) were studied. Exercise duration was significantly higher on the HI estrogen day, but no significant differences in hemodynamic response to exercise were found between the two study days. There were also no significant differences with respect to heart rate (HR) acceleration during early exercise, as well as resting and peak RVSP, HR, blood pressure, and rate pressure product. Doppler-estimated RVSP demonstrated a linear relationship to HR at a ratio of 1 mm Hg (1 mm Hg = 133.3224 Pa) for every 5 bpm (beats per minute) increase in HR. There were no differences in the slope of this relationship between HI and LO estrogen phases of the menstrual cycle. Our findings did not demonstrate any effect of endogenous estrogen levels on the modulation of the pulmonary vascular response to exercise in healthy women.

Complications from recruitment maneuvers in patients with acute lung injury: secondary analysis from the lung open ventilation study.

BACKGROUND: There are limited data on the safety and efficacy of recruitment maneuvers (RMs) in acute lung injury (ALI) patients. OBJECTIVE: To evaluate the frequency, timing, and risk factors for complications from RMs in adult ALI patients. METHODS: Secondary analysis of data from a randomized controlled trial of a lung open ventilation strategy that included sustained inflation RMs. RESULTS: Respiratory (eg, desaturation) and cardiovascular (eg, hypotension) complications from recruitment maneuvers were common (22% of all patients receiving RMs), and the majority occurred within 7 days of enrollment. New air leak through an existing chest tube was uncommon (< 5%). As compared to patients receiving 1 or fewer RMs, the number of RMs received was associated with increased risk in both younger (age ≤ 56 y) and older patients (age > 56 y): 2 RMs odds ratio [OR] 6.92 (95% CI 1.70-28.2), ≥ 3 RMs OR 15.4 (95% CI 4.77-49.6), and 2 RMs OR 5.43 (95% CI 1.76-16.8), ≥ 3 RMs OR 4.93 (95% CI 1.78-13.7), respectively. Patients with extrapulmonary ALI had decreased odds of developing complications (OR 0.42, 95% CI 0.22-0.80). CONCLUSIONS: Complications in adult ALI patients receiving RMs were common, but serious complications (eg, new air leak through an existing chest tube) were infrequent. There is a significant association between the number of RMs received and complications, even after controlling for illness severity and duration. Given their uncertain benefit in ALI patients, and the potential for complications with repeated application, the routine use of sustained inflation RMs is not justified.

Examining nursing vital signs documentation workflow: barriers and opportunities in general internal medicine units.

AIMS: To characterise the nursing practices of vital signs collection and documentation in a general internal medicine environment to inform strategies for improving workflow design. BACKGROUND: Clinical workflow analysis is critical to identify barriers and opportunities in current processes. Analysis can guide the design and development of novel technological solutions to produce greater efficiencies and effectiveness in healthcare delivery. Research surrounding vital signs documentation workflow in general internal medicine environments has received very little attention making it difficult to compare the effectiveness of new technologies. DESIGN: Qualitative ethnographic analyses and quantitative time-motion study were conducted. METHODS: Workflows of 24 nurses at three hospitals in five general internal medicine environments were captured, and timeliness of vital signs assessment and documentation was measured. RESULTS: Clinical assessment of vital signs was consistent, but the documentation process was highly variable within groups and between hospitals. Two themes characterised workflow barriers surrounding point-of-care documentation. First, a lack of standardised documentation methods for vital signs resulted in higher rates of transcription, increasing not only the likelihood of errors but delays in recording and accessibility of information. Second, despite advancements in electronic documentation systems, the observed system was not conducive to point-of-care documentation. Average electronic documentation was significantly longer than paper documentation. Nurses developed ad hoc workarounds that were inefficient and undermined the intent of electronic documentation. CONCLUSION: We have identified barriers and opportunities to improve the efficiency of nursing vital signs documentation. Changes in technology, workflows and environmental design allow for significant improvements and deserve further exploration. RELEVANCE TO CLINICAL PRACTICE: Attention to clinical practice and environments can improve the workflow of prompt vital signs documentation and increase clinical productivity and timeliness of information for clinical decisions, as well as minimising transcription errors leading to safer patient care.

Clinical Implications of Body Composition and Exercise Capacity Following Pulmonary Endarterectomy.

BACKGROUND: Pulmonary endarterectomy (PEA) is a curative procedure for patients with chronic thromboembolic pulmonary hypertension. Body composition and exercise capacity have been associated with adverse outcomes in patients undergoing cardiothoracic operations, but their significance with PEA is unclear. We evaluated the association of body composition and 6-minute walk distance (6MWD) with disease severity, hospital length of stay, discharge disposition, and postoperative functional recovery. METHODS: This was a retrospective, single-center cohort study of patients who underwent PEA (January 2014-December 2017). Body composition (skeletal muscle mass and adiposity cross-sectional area) was quantified using thoracic computed tomography with sliceOmatic (TomoVision, Magog, QC, Canada) software. Body mass index was calculated. Association of body composition measures and 6MWD with clinical outcomes was evaluated using multivariable regression models. RESULTS: The study included 127 patients (42% men), aged 58 ± 14 years; body mass index was 31 ± 7 kg/m2 and 6MWD was 361 ± 165 m). Muscle and 6MWD were associated with disease severity measures. Of those surviving hospitalization (n = 125), a greater 6MWD was associated with a shorter hospital stay (1.9 median days per 100 m; p < .001) and higher likelihood of being discharged directly home from hospital (odds ratio, 2.1 per 100 m; P = .004), independent of age, sex, and body mass index. Those with a lower preoperative 6MWD (per 100 m) had a greater increase in their postoperative 6MWD (52 m; P < .0001), independent of age, sex, and body mass index. Body composition measures were not associated with hospital outcomes or exercise capacity in the first year postoperatively. CONCLUSIONS: Exercise capacity was a more prognostic marker of PEA outcomes compared with body composition. Future research is needed to explore pre-PEA rehabilitation strategies.

The role of exercise right heart catheterization to guide pulmonary hypertension therapy in older adults.

The spectrum of patients referred for suspected pulmonary arterial hypertension (PAH) includes a population with clinical features suggestive of pulmonary hypertension due to left heart disease (PH-LHD). Even after right heart catheterization (RHC) performed at rest, it can be a challenge to identify patients who will clearly benefit from PAH drug therapy. Therefore, the objective of this study was to evaluate the role of exercise RHC to influence decisions regarding prescription of PAH drug therapy in this population. A retrospective cohort study was conducted of older adults with risk factors for PH-LHD and suspected PH referred for exercise RHC. One year follow-up was conducted to record clinical outcomes, all changes in PAH drug therapy, and changes in patient-reported quality of life. The final cohort included 61 patients, mean age of 69 ± 10; 44% and 34% had a history of coronary artery disease and atrial fibrillation respectively. Exercise changed the proportional breakdown of hemodynamic diagnoses from 36% No PH, 44% PAH, and 20% PH-LHD at rest to 15% No PH, 36% PAH, and 49% PH-LHD. Although a significant proportion of patients were reclassified as PH-LHD, there was an overall increase in the proportion of patients receiving PAH drug therapy, particularly for those with PAH confirmed by exercise RHC. A total of 11 PAH drug prescriptions were employed before exercise RHC increasing to 24 after (p = 0.002). Patients receiving PAH therapy demonstrated significant improvement in self-reported quality of life. Exercise RHC appeared to influence selection of PAH drug therapy.

Vasopressin versus norepinephrine infusion in patients with septic shock.

BACKGROUND: Vasopressin is commonly used as an adjunct to catecholamines to support blood pressure in refractory septic shock, but its effect on mortality is unknown. We hypothesized that low-dose vasopressin as compared with norepinephrine would decrease mortality among patients with septic shock who were being treated with conventional (catecholamine) vasopressors. METHODS: In this multicenter, randomized, double-blind trial, we assigned patients who had septic shock and were receiving a minimum of 5 microg of norepinephrine per minute to receive either low-dose vasopressin (0.01 to 0.03 U per minute) or norepinephrine (5 to 15 microg per minute) in addition to open-label vasopressors. All vasopressor infusions were titrated and tapered according to protocols to maintain a target blood pressure. The primary end point was the mortality rate 28 days after the start of infusions. RESULTS: A total of 778 patients underwent randomization, were infused with the study drug (396 patients received vasopressin, and 382 norepinephrine), and were included in the analysis. There was no significant difference between the vasopressin and norepinephrine groups in the 28-day mortality rate (35.4% and 39.3%, respectively; P=0.26) or in 90-day mortality (43.9% and 49.6%, respectively; P=0.11). There were no significant differences in the overall rates of serious adverse events (10.3% and 10.5%, respectively; P=1.00). In the prospectively defined stratum of less severe septic shock, the mortality rate was lower in the vasopressin group than in the norepinephrine group at 28 days (26.5% vs. 35.7%, P=0.05); in the stratum of more severe septic shock, there was no significant difference in 28-day mortality (44.0% and 42.5%, respectively; P=0.76). A test for heterogeneity between these two study strata was not significant (P=0.10). CONCLUSIONS: Low-dose vasopressin did not reduce mortality rates as compared with norepinephrine among patients with septic shock who were treated with catecholamine vasopressors. (Current Controlled Trials number, ISRCTN94845869 [controlled-trials.com].).