New research was presented at CHEST 2018, The Annual International Scientific Assembly of the American College of Chest Physicians, from October 6 to 10 in San Antonio. The features below highlight some of the studies presented at the conference.
Type 2 Diabetes & Sepsis Outcomes
Research has shown that diabetes is a pro-inflammatory state that increases susceptibility for severe infections, including sepsis. While other studies suggest that liberal blood sugar control can reduce mortality in critically ill patients, subgroup analysis found it also appeared to increase infection incidence. To examine the effects of diabetes on sepsis admissions, researchers assessed the short-term, in-hospital outcomes and rate or organ failure among nearly 650,000 sepsis admissions that included more than 205,000 patients with type 2 diabetes. Mortality rates were 13.4% among non-diabetics and 11.1% among diabetics, while those with type 2 diabetes had increased length of stay (7.7 vs 7.6 days), age at admission (68.7 vs 65.7 years), and number of chronic conditions (8.0 vs 6.0). Non-diabetics had either similar or increased rates of various types of organ failure when compared with diabetics. The study authors suggest that clinicians be proactive with sepsis care regardless of patients’ diabetic status.
Improving LTV Ventilation Compliance
Despite widely acknowledged numerous benefits in mechanically vented (MV) patients with and without acute respiratory syndrome (ARDS), adherence rates to low tidal volume (LTV)/lung protective ventilation remain low. To determine if a decision support software system providing real-time, bedside alerts can improve LTV adherence for MV patients, adherence rates before and after implementation of such a system were compared between patients randomized to the intervention and a control group. The decision support system displayed real-time surveillance data and warnings on a large video screen above each ICU patient’s bed. Data included tidal volume per probable body weight (TV PBW) and partial pressure of oxygen/fraction of inspired oxygen ratio (P/F) with values displayed in red, yellow, or green, and a dedicated “ventilator bundle” window that flashed yellow or red if the TV PBW or P/F were within warning ranges. Among patients with ARDS, LTV adherence rates were 40.3% prior to implementation and 65.6% after. For all patients on MV, rates of those ventilated at more than 8 ml/kg PBW were 13.5% prior to implementation and 7.8% after.
Outcomes of MICU Patients With ESRD
While patients with known end-stage renal disease (ESRD) are commonly admitted with respiratory failure or sepsis, data are lacking on their outcomes. For a study of patients admitted to the medical ICU (MICU) with ESRD, investigators evaluated factors affecting outcomes and the performance of Simplified Acute Physiology Score (SAPS) II and Sequential Organ Failure Assessment (SOFA) scores to predict mortality. Among those with ESRD, MICU mortality, in-hospital mortality, ICU readmission, and 30-day readmission rates were 17.7%, 21.2%, 5.3%, and 27.4%, respectively. Average MICU lengths of stay (LOS) was 3.91 days, mean SOFA score was 6.63, mean SAPS-II score was 50.5, 36.3% were on mechanical ventilation, and 4.4% required vasopressor support. The general MICU population during the study period had a LOS of 3.4 days and a mortality rate of 14.7%. Mechanical ventilation and higher SAPS-II and SOFA scores were associated with increased ICU mortality risk.
Vitamin C & Sepsis-Related Mortality
Various studies have indicated several benefits of the administration of vitamin C in patients with sepsis. To gather more supporting data regarding the use of vitamin C in this patient population, researchers conducted a meta-analysis to calculate pooled outcomes for mortality rate, length of ICU stay, and duration of vasopressor use across three studies. Among patients with sepsis, the mortality rate was significantly lower for those who received vitamin C (13%) when compared with those who did not (48%). Patients administered vitamin C also had a significantly shorter length of stay (mean difference of -1.49 days) and duration of vasopressor use (mean difference of -30.22 hours).
Deciding on ICU Admission for Substance Overdose
While ICU-level interventions are required for some patients presenting with substance overdose—whether prescription or recreational—evidence suggests that many who are admitted to the ICU do not. For a study, researchers assessed the accuracy of a set of clinical criteria in identifying patients with substance overdose who may require ICU-level interventions. ICU admission was determined to be indicated by respiratory rate (≤8 or ≥30 per minute), oxygen saturation (<90%), systolic blood pressure (<90 or >200 mmHg), Glascow Coma Scale sore (<14), and QRS duration on electrocardiogram (>120 milliseconds). Among participants, 81% had one or more abnormal criteria, among whom 20% received ICU-level interventions. Sensitivity of the above-stated criteria in identifying patients needing ICU care was 94.4%, while specificity was 21.6%. Among those who did not require ICU-level intervention but were admitted to the ICU, the criteria would have accurately predicted that 16.7% did not require ICU admission.
Predicting Ventilation Escalation in Patients With COPD
Although previous research indicates that non-invasive ventilation (NIV) is effective in improving overall clinical outcomes in the treatment of acute exacerbations of COPD, escalation to invasive ventilation can occur. To identify underlying comorbidities and clinical characteristics that may contribute to the need for invasive ventilation in this patient population, study investigators examined data on adults with a COPD exacerbation who were initially treated with NIV within 24 hours of admission. Alcohol abuse (hazard ratio [HR], 1.85), fluid and electrolyte abnormalities—including derangements in sodium, potassium, acid-base disorders, and hyper- or hypovolemia— (HR, 1.30), and pulmonary circulation disorders (HR, 4.19) were found to be associated with increased rates of intubation.
LAMAs Not Tied to CV Risk in COPD
Previous research has providing conflicting results on whether or not long-acting antimuscarininc antagonists (LAMAs) are associated with increased risk of cardiovascular (CV) events. For a study, researchers followed patients with moderate to very severe COPD who were taking LAMAs for 3 years and were at increased risk of CV events based on either a history of having a CV event or CV risk factors. Their rates of CV events were compared with those of placebo controls. No signs of excess CV events were observed in patients on LAMAs. Among patients with a previous CV event, 5.5% of those on LAMAs have a major acute cardiac event during the study period, compared with 6.2% of those on placebo. Among those with at least two risk factors, the rate of these events was 2.4% for both groups. Relative risks for COPD exacerbations were 24% and 20% lower for those on LAMAs who had a previous CV event or at least two risk factors, respectively.
Environmental Exposures & Pediatric Asthma Control
Second hand smoke and some animals are among environmental exposures that have been suggested to impact asthma control. Whether such exposures impact asthma control among children whose asthma is managed per National Asthma Education and Prevention Program guidelines was the focus of a 3-year prospective cohort study. Children with uncontrolled asthma at baseline were provided care as per NAEPP guidelines. Among all participants, regardless of environmental exposures, acute care need scores improved significantly by 3 to 6-month follow-up visit and persisted to the 3-year follow-up visit. Environmental exposure to smoke or animals was determined to not be significant covariates in asthma improvement over time.
Care Bundle Cuts COPD Readmission
Occurring in 60% of patients within 1 year of discharge, according to study findings, COPD remains the third most common cause of readmission among Medicare beneficiaries. To determine if a COPD care bundle delivered by a multidisciplinary healthcare team can help reduce readmission rates for acute exacerbations in this patient population, researchers conducted a pre- versus post-intervention study. The evidence-based COPD care bundle included patient education on COPD prior to discharge, completion of an individualized self-management COPD action plan to be used by patients after discharge, and timely outpatient follow-up with a pulmonologist. Rates of 30-day readmission were 22.2% and 32.7% for the post- and pre-intervention groups. The post-intervention group also had lower 60-day (30.3% vs 56.0%) and 90-day (35.3% vs 62.6%) readmission rates. Hospital length of stay was similar in both groups.
Smoking & Erectile Dysfunction
While previous research has shown a direct relationship between cigarette smoking (number of years smoking and amount of cigarettes smoked) with erectile dysfunction (ED), evidence suggests that public knowledge of this association is low, perhaps due in part to the lack of impotence warning on cigarette packaging. Researchers conducted a study aimed at adult male smokers to evaluate community awareness of this causal relationship and its impact on smoking habits. Among the 96% of participants who were current smokers (4% formal smokers), 39% smoked for more than 20 years and 45% smoked more than a pack per day. While 97% reported lung cancer as the main hazard of smoking and 47% reported heart disease as likely to be related to smoking, only 13% knew of the association between smoking and ED. All respondents admitted that adequate knowledge of the association between these three conditions and smoking would mostly likely encourage them to quit smoking.
Reducing Unnecessary Chest X-Rays
Although the American College of Radiology (ACR) recommends against routine daily chest x-rays (CXR) in clinically stable, intubated ICU patients, studies suggest that this practice remains common and contributes to an estimated $250 to $325 billion spent annually on unnecessary and/or inappropriate diagnostics. For a study, root cause analysis and resident surveys were used to determine factors that lead to ordering routine, daily CXRs prior to implementing a resident and attending education intervention consisting of monthly teaching for medical ICU residents on the ACR CXR Appropriateness Criteria, a similar session for MICU attendings, and monthly faculty meeting reminders. Between the 8 weeks prior to implementing the intervention and the 8 weeks after, a statistically significant 19% reduction in CXRs per patient-day was observed, with no statistical significance between ICU length of stay or mortality rates. Senior resident, fellow, and attending influence were predominant factors that lead to CXR ordering on stable, intubated patients.
Comparing Approaches to Lung Collapse Management
Few studies have assessed outcomes and best management of patients with lung collapse. Patients with complete or near-complete lung collapse were enrolled in a study to evaluate outcomes of interventional management with fiberoptic bronchoscopy (FOB) versus a conservative approach. No differences were observed between the degree of resolution of lung collapse, hospital length of stay, or mortality between patients treated with either approach. However, when compared with patients who underwent FOB after 24 hours of diagnosis of lung collapse, those who underwent the procedure within 24 hours had non-statistical increased likelihood of achieving complete and near complete resolution (44.4% vs 15.4%). Also, endobronchial lesions were found in 27.5% of those who underwent FOB, with 22.5% found to be malignant.