Hospital trajectories and early predictors of clinical outcomes differ between SARS-CoV-2 and influenza pneumonia

BACKGROUND

A comparison of pneumonias due to SARS-CoV-2 and influenza, in terms of clinical course and predictors of outcomes, might inform prognosis and resource management. We aimed to compare clinical course and outcome predictors in SARS-CoV-2 and influenza pneumonia using multi-state modelling and supervised machine learning on clinical data among hospitalised patients.

METHODS

This multicenter retrospective cohort study of patients hospitalised with SARS-CoV-2 (March-December 2020) or influenza (Jan 2015-March 2020) pneumonia had the composite of hospital mortality and hospice discharge as the primary outcome. Multi-state models compared differences in oxygenation/ventilatory utilisation between pneumonias longitudinally throughout hospitalisation. Differences in predictors of outcome were modelled using supervised machine learning classifiers.

FINDINGS

Among 2,529 hospitalisations with SARS-CoV-2 and 2,256 with influenza pneumonia, the primary outcome occurred in 21% and 9%, respectively. Multi-state models differentiated oxygen requirement progression between viruses, with SARS-CoV-2 manifesting rapidly-escalating early hypoxemia. Highly contributory classifier variables for the primary outcome differed substantially between viruses.

INTERPRETATION

SARS-CoV-2 and influenza pneumonia differ in presentation, hospital course, and outcome predictors. These pathogen-specific differential responses in viral pneumonias suggest distinct management approaches should be investigated.

FUNDING

This project was supported by NIH/NCATS UL1 TR002345, NIH/NCATS KL2 TR002346 (PGL), the Doris Duke Charitable Foundation grant 2015215 (PGL), NIH/NHLBI R35 HL140026 (CSC), and a Big Ideas Award from the BJC HealthCare and Washington University School of Medicine Healthcare Innovation Lab and NIH/NIGMS R35 GM142992 (PS).

Sympathetic stimulation increases serum lactate concentrations in patients admitted with sepsis: implications for resuscitation strategies

BACKGROUND

Diametrically opposed positions exist regarding the deleterious effects of elevated lactate. There are data suggesting that it is a detrimental proxy for tissue hypoperfusion and anaerobic metabolism in sepsis and an alternative viewpoint is that some of the hyperlactatemia produced maybe adaptive. This study was conducted to explore the relationship between serum lactate levels, mean arterial blood pressure (MAP), and sympathetic stimulation in patients with sepsis.

METHODS

Retrospective analysis of prospectively collected clinical data from four community-based hospitals and one academic medical center. 8173 adults were included. Heart rate (HR) was used as a surrogate marker of sympathetic stimulation. HR, MAP, and lactate levels were measured upon presentation.

RESULTS

MAP and HR interacted to affect lactate levels with the highest levels observed in patients with low MAP and high HR (3.6 mmol/L) and the lowest in patients with high MAP and low HR (2.2 mmol/L). The overall mortality rate was 12.4%. Each 10 beats/min increase in HR increased the odds of death 6.0% (95% CI 2.6% to 9.4%), each 1 mmol/L increase in lactate increased the odds of death 20.8% (95% CI 17.4% to 24.2%), whereas each 10 mmHg increase in MAP reduced the odds of death 12.3% (95% CI 9.2% to 15.4%). However, HR did not moderate or mediate the association between lactate and death.

CONCLUSIONS

In septic patients, lactate production was associated with increased sympathetic activity (HR ≥ 90) and hypotension (MAP < 65 mmHg) and was a significant predictor of mortality. Because HR, lactate, and MAP were associated with mortality, our data support the present strategy of using these measurements to gauge severity of illness upon presentation. Since HR did not moderate or mediate the association between lactate and death, criticisms alleging that lactate caused by sympathetic stimulation is adaptive (i.e., less harmful) do not appear substantiated.

Sepsis, the Administration of IV Fluids, and Respiratory Failure: A Retrospective Analysis-SAIFR Study

BACKGROUND

Although resuscitation with IV fluids is the cornerstone of sepsis management, consensus regarding their association with improvement in clinical outcomes is lacking.

RESEARCH QUESTION

Is there a difference in the incidence of respiratory failure in patients with sepsis who received guideline-recommended initial IV fluid bolus of 30 mL/kg or more conservative resuscitation of less than 30 mL/kg?

STUDY DESIGN AND METHODS

This was a retrospective analysis of prospectively collected clinical data conducted at an academic medical center in Omaha, Nebraska. We abstracted data from 214 patients with sepsis admitted to a single academic medical center between June 2017 and June 2018. Patients were stratified by receipt of guideline-recommended fluid bolus. The primary outcome was respiratory failure defined as an increase in oxygen flow rate or more intense oxygenation and ventilation support; oxygen requirement and volume were measured at admission, 6 h, 12 h, 24 h, and at discharge. Subgroup analyses were conducted in high-risk patients with congestive heart failure (CHF) as well as those with chronic kidney disease (CKD).

RESULTS

A total of 62 patients (29.0%) received appropriate bolus treatment. The overall rate of respiratory failure was not statistically different between patients who received appropriate bolus or did not (40.3% vs 36.8%; P = .634). Likewise, no differences were observed in time to respiratory failure (P = .645) or risk of respiratory failure (adjusted hazard ratio, 1.1 [95% CI, 0.7-1.7]; P = .774). Results were similar within the high-risk CHF and CKD subgroups.

INTERPRETATION

In this single-center retrospective study, we found that by broadly defining respiratory failure as an increase in oxygen requirements, a conservative initial IV fluid resuscitation strategy did not correlate with decreased rates of hypoxemic respiratory failure.

Exploration of Novel Co-processed Multifunctional Diluent for the Development of Tablet Dosage Form

The aim of this investigation was to develop a novel multifunctional co-processed diluent consisting of microcrystalline cellulose (Avicel PH 102), crospovidone (Polyplasdone XL) and polyethylene glycol 4000. Colloidal silicon dioxide and talc were also incorporated as minor components in the diluent to improve tableting properties. Melt granulation was adopted for preparation of co-processed diluent. Percentage of Avicel PH 102, Polyplasdone XL and polyethylene glycol 4000 were selected as independent variables and disintegration time was chosen as a dependent variable in simplex lattice design. The co-processed diluent was characterised for angle of repose, bulk density, tapped density, Carr's index, percentage of fines and dilution potential study. Acetaminophen and metformin were used as poorly compressible model drugs for preparation of tablets. The blend of granules of drug and extra-granular co-processed diluent exhibited better flow as compared to the blend of drug granules and physical mixture of diluents blend. The diluent exhibited satisfactory tableting properties. The tablets exhibited fairly rapid drug release. In conclusion, melt granulation is proposed as a method of preparing co-processed diluent. The concept can be used to bypass patents on excipient manufacturing.

Unsuccessful deflation of a bifoil balloon during percutaneous mitral valvuloplasty

A middle-aged woman was subjected to balloon mitral valvuloplasty using a bifoil balloon catheter. After inflation the balloon failed to deflate in spite of negative suction, probably due to a kink. The balloon was perforated with a transseptal puncture needle in order to deflate it and save open heart surgery.

Tricuspid balloon valvuloplasty: a more simplified approach using inoue balloon

We report a more simplified technique of the balloon tricuspid valvuloplasty using inoue balloon set in a patient suffering from severe rheumatic tricuspid stenosis. We believe that this technique may be useful in a difficult case of tricuspid valvuloplasty.

Percutaneous transvenous mitral commissurotomy using Inoue balloon catheter: a left femoral vein approach

Percutaneous transvenous mitral commissurotomy by the Inoue technique is usually recommended from right femoral vein approach only. We report an unusual patient in whom the left femoral vein approach was used successfully. We believe that the left femoral vein approach can be reserved as a last resort in certain cases.

Difficult mitral valvuloplasty: an "over the wire" modification of Inoue technique

Failure to cross the mitral valve remains an important cause of the technical failure in performing mitral valvuloplasty with the Inoue technique, especially during initial experience of the operator. We report two such cases where conventional methods failed and an "over the wire" modification of the Inoue technique had to be utilized. This particular modification can be beneficial in the rare cases where negotiating the Inoue balloon across the mitral valve is particularly difficult.

Left ventricular mass and function in children with severe protein energy malnutrition

We studied 25 children, aged 1-5 years (mean 2.65 +/- 0.8 years) with severe protein energy malnutrition, and compared their left ventricular mass and function to those of 26 healthy, age- and sex-matched normal children. The mean left ventricular mass in the patients was lower than that in the controls (25.75 +/- 8.09 g vs. 32.44 +/- 11.64 g; P less than 0.05, C.I. 2.08 to 11.30). However, left ventricular mass (g)/kg body weight was significantly increased in the patients (4.44 +/- 1.45 vs. 2.42 +/- 0.87; P less than 0.001, C.I. 1.28 to 2.76) suggesting relative cardiac "sparing". The systolic function indices like ejection fraction, percentage fractional shortening, and velocity of circumferential fiber shortening were not significantly different in the patients and in the normal children. The left ventricular end-diastolic volume, stroke volume and cardiac output were reduced in proportion to decrease in body size in the patients, so that the cardiac index was not reduced but slightly increased in the patients. (5.95 +/- 1.9 l/min/m2 in patients, 4.97 +/- 1.4 l/min/m2 in controls; P less than 0.05, C.I. 0.04 to 1.92). There was no significant difference in any of these parameters of left ventricular function or mass in patients with marasmus, as compared to those of patients with marasmic kwashiorkor. Amongst the 25 patients, however, 5 patients (20%) had an ejection fraction of less than 50%. Compared to the other 20 patients, these 5 patients had lower left ventricular mass (18.4 +/- 4.3 g vs. 27.5 +/- 7.8 g, P less than 0.05 C.I. 1.63 to 16.75), lower left ventricular mass (g)/kg body weight and a worse prognosis.(ABSTRACT TRUNCATED AT 250 WORDS)

Noninvasive assessment of left ventricular function in asymptomatic diabetics and its relation to metabolic control and microangiopathy

Fifty otherwise healthy patients with diabetes mellitus (37 males, 13 females; mean age: 53 +/- 10 years) of more than five year duration were compared with twenty six healthy age and sex matched controls. Detailed echocardiographic evaluation was done in all and systolic time intervals (STI) were measured. In diabetics, metabolic control and presence of microangiopathy were evaluated. PEP Index (patients: 146.23 +/- 17.04; controls: 121.99 +/- 5.15; p less than 0.001), PEP/LVET ratio (patients: 0.38 +/- 0.07; controls: 0.32 +/- 0.02; p less than 0.001), LVEF% (patients: 54.1 +/- 10.56; controls: 64.71 +/- 6.33; p less than 0.001), all were significantly altered in diabetics suggesting left ventricular dysfunction. The left ventricular posterior wall thickness (patients: 0.96 +/- 0.23 cm; controls: 0.85 +/- 0.12 cm; p less than 0.01) and interventricular septal thickness (patients: 1.2 +/- 0.24 cm; controls: 0.87 +/- 0.25 cm; p less than 0.001) in diastole were increased in diabetics. The PEPI correlated with day-to-day control but not with chronic glycemic control of diabetes mellitus. The PEP/LVET was significantly increased in patients with severe, as compared to those with none or mild microangiopathy (p less than 0.05). Thus, significant left ventricular dysfunction is evident in asymptomatic, otherwise healthy diabetics. Both metabolic control and microangiopathy may be responsible for the abnormalities.