Beyond Trauma: High-Volume Critical Care Medicine in a Military Medical Center-Based Military-Civilian Partnership.

INTRODUCTION: Critical Care Internal Medicine (CCIM) is vital to the U.S. Military as evidenced by the role CCIM played in the COVID-19 pandemic response and wartime operations. Although the proficiency needs of military surgeons have been well studied, this has not been the case for CCIM. The objective of this study was to compare the patient volume and acuity of military CCIM physicians working solely at Military Treatment Facilities (MTFs) with those at MTFs also working part-time in a military-civilian partnership (MCP) at the University Medical Center of Southern Nevada (UMC). MATERIALS AND METHODS: We analyzed FY2019 critical care coding data from the Military Health System and UMC comparing the number of critical care encounters, the number of high-acuity critical care encounters, and the Abilities/Activity component of the Knowledge, Skills, and Abilities/Clinical Activity (KSA) score. This analysis was restricted to critical care encounters defined by Current Procedural Terminology codes for critical care (99291 and 99292). A critical care encounter was considered high acuity if the patient had ICD-10 codes for shock, respiratory failure, or cardiac arrest or had at least three codes for critical care in the same episode. RESULTS: The five AF CCIM physicians in the MCP group performed 2,019 critical care encounters in 206 days, with 63.1% (1,273) being defined as high acuity. The total number of MTF critical care encounters was 16,855 across all providers and services, with 28.9% (4,864) of encounters defined as high acuity. When limited to CCIM encounters, MTFs had 6,785 critical care encounters, with 32.0% being high acuity (2,171). Thus, the five AF CCIM physicians, while working 206 days at the UMC, equated to 12.0% (2,019/16,855) of the total critical care MTF encounters, 27.2% (1,273/4,684) of the total high-acuity MTF critical care encounters, and 29.8% (2,019/6,785) of the MTF CCIM encounters, with 58.6% (1,273/2,171) of the MTF CCIM high-acuity encounters.The USAF CCIM physicians in the MCP group performed 454,395 KSAs in 206 days, with a KSA density per day of 2,206. In the MTF group, CCIM providers generated 2,344,791 total KSAs over 10,287 days, with a KSA density per day of 227.9. Thus, the five CCIM physicians at the UMC accounted for 19.38% of the MTF CCIM KSAs, with a KSA density over 10 times higher (2,206 vs. 227.9). CONCLUSIONS: The volume and acuity of critical care at MTFs may be insufficient to maintain CCIM proficiency under the current system. Military-civilian partnerships are invaluable in maintaining clinical proficiency for military CCIM physicians and can be done on a part-time basis while maintaining beneficiary care at an MTF. Future CCIM expeditionary success is contingent on CCIM physicians and team members having the required CCIM exposure to grow and maintain clinical proficiency.Limitations of this study include the absence of off-duty employment (moonlighting) data and difficulty filtering military data down to just CCIM physicians, which likely caused the MTF CCIM data to be overestimated.

Baseline Spirometry as a Predictor of Positive Methacholine Challenge Testing for Exertional Dyspnea.

BACKGROUND: There are several tests recommended by the American Thoracic Society (ATS) to evaluate for airway hyper-responsiveness (AHR), one of which is methacholine challenge testing (MCT). Few studies have examined the correlation of baseline spirometry to predict AHR in MCT, especially in the younger, relatively healthy military population under clinical evaluation for symptoms of exertional dyspnea. The study aim was to retrospectively correlate baseline spirometry values with MCT responsiveness. METHODS: This study is a retrospective review of all MCT performed at Brooke Army Medical Center/Wilford Hall Medical Center over a 12-y period; all completed studies were obtained from electronic databases. The following parameters were analyzed from the studies: baseline FEV1, FVC, FEV1/FVC, mid-expiratory flow (FEV25-75%), FEV25-75%/FVC. Studies were categorized based on baseline obstruction, restriction, FEF25-75% lower limit of normal, and response to bronchodilator testing (if completed); these values were compared based on methacholine reactivity and severity. RESULTS: Methacholine challenge studies (n = 1,933) were reviewed and categorized into reactive (n = 577) and nonreactive (n = 1,356) as determined by ATS guidelines. The mean baseline FEV1 (% predicted) with MCT reactivity was 88.0 ± 13.0% versus no MCT reactivity was 92.7 ± 13.0% (P < .001). The mean baseline FVC (% predicted) was 93.1 ± 13.7% versus 95.3 ± 13.5% (P < .001). The mean baseline FEV25-75% (% predicted) was 80.0 ± 22.1% versus 89.0 ± 23.4% (P < .001). Based on partition analysis, methacholine reactivity was most prevalent with baseline obstruction, n = 115 (43%), and in the absence of obstruction, when the FEF25-75% (% predicted) was below 0.70, n = 111 (40%). The negative predictive value with normal spirometry was 73%. CONCLUSIONS: The analysis of baseline spirometry prior to MCT proved useful in the evaluation of exertional dyspnea in a military population. The presence of airways obstruction (FEV1/FVC < lower limit of the normal range) followed by a reduction in FEV25-75% < 70% predicted showed a positive correlation with underlying AHR. In patients with exertional dyspnea and normal baseline spirometry, the use of the FEF25-75% may be a useful surrogate measurement to predict reactivity during MCT and consideration for additional testing or treatment.

Evaluation of Supranormal Spirometry Values With an Obstructive Ratio for Airway Hyperreactivity.

BACKGROUND: Published guidelines on spirometry interpretation suggest an elevated FVC and FEV1 > 100% of predicted with an obstructive ratio may represent a physiological variant. Further evidence is needed on whether this finding indicates symptomatic airways obstruction and what additional evaluation should be done. METHODS: Participants were prospectively enrolled to undergo additional testing for a technically adequate spirometry study with an FEV1 > 90% of predicted, and FEV1/FVC below the lower limit of normal, based on 95th percentile confidence intervals. Further testing consisted of full pulmonary function testing, impulse oscillometry (IOS), post-bronchodilator testing, fractional exhaled nitric oxide (FeNO), and methacholine challenge testing (MCT). RESULTS: A total of 49 patients meeting entry criteria enrolled and completed testing. Thirty-three were considered symptomatic based on clinical indications for initial testing and 16 were considered asymptomatic. Baseline pulmonary function test values were not different between groups while IOS R5 values (% predicted) were higher in the symptomatic group (126.5 ± 0.37 vs 107.1 ± 0.31). Bronchodilator responsiveness on PFT or IOS was infrequent in both groups. There was a 29% positivity rate for MCT in the symptomatic group compared to one borderline study in asymptomatic participants. FeNO was similar for symptomatic, 26.17 ± 31.3 ppb, compared to asymptomatic, 22.8 ± 13.5 ppb (p = 0.93). The dysanapsis ratio was higher in the symptomatic (0.15 ± 0.03) compared to the asymptomatic (0.13 ± 0.02) (p < 0.05). CONCLUSION: Normal FEV1 > 90% of predicted and obstructive indices may not represent a normal physiological variant in all patients. In symptomatic patients, a positive MCT and elevated baseline IOS values were more common than in asymptomatic patients with similar PFT characteristics. These findings suggest that clinicians should still evaluate for airway hyperresponsiveness in patients with exertional dyspnea with airway obstruction and FEV1 > 90% of predicted and consider alternative diagnoses to include a normal physiologic variant if non-reactive.

Longitudinal Changes in Spirometry in Deployed Air Force Firefighters.

INTRODUCTION: Inhalational exposures are common among service members who deploy to southwest Asia. The objective of this study is to determine if deployed Air Force firefighters have any decline in spirometry related to deployment. METHODS: This study is a retrospective chart review. RESULTS: The database search identified 302 firefighters with documentation of two separate spirometry examinations. For deployed firefighters, mean change in forced expiratory volume at 1 second (FEV1) percent predicted was -1.01 ±â€Š7.86, forced vital capacity (FVC) was -0.46 ±â€Š10.26 predicted, and mid-expiratory flow (FEF25-75) was -0.13 ±â€Š12.97. For firefighters who had never deployed, mean change in FEV1 percent predicted was +0.08 ±â€Š7.09, FVC was +0.72 ±â€Š7.75, and FEF25-75 was -0.66 ±â€Š16.17. CONCLUSION: There does not appear to be evidence that deployment causes a significant change in lung function as measured by spirometry.

Clinical Evaluation of Deployed Military Personnel With Chronic Respiratory Symptoms: Study of Active Duty Military for Pulmonary Disease Related to Environmental Deployment Exposures (STAMPEDE) III.

BACKGROUND: Chronic respiratory symptoms are frequently reported after Southwest Asia deployment in support of combat operations. The full spectrum of clinical lung diseases related to these deployments is not well characterized. METHODS: Military personnel with chronic symptoms, primarily exertional dyspnea, underwent a standardized cardiopulmonary evaluation at two tertiary medical centers. Pulmonary function testing consisted of spirometry, lung volume, diffusing capacity, impulse oscillometry, and bronchodilator testing. Further testing included methacholine challenge, exercise laryngoscopy, high-resolution CT scan, ECG, and transthoracic echocardiography. RESULTS: A total of 380 participants with a mean age of 38.5 ± 8.4 years completed testing. Asthma was the most common diagnosis in 87 patients (22.9%) based on obstructive spirometry/impulse oscillometry and evidence of airway hyperreactivity, whereas another 57 patients (15.0%) had reactivity with normal spirometry. Airway disorders included 25 (6.6%) with laryngeal disorders and 16 (4.2%) with excessive dynamic airway collapse. Interstitial lung disease was identified in six patients (1.6%), whereas 11 patients (2.9%) had fixed obstructive lung disorders. Forty patients (10.5%) had isolated pulmonary function abnormalities and 16 (4.2%) had miscellaneous disorders. The remaining 122 patients (32.1%) with normal studies were classified as undiagnosed exertional dyspnea. Significant comorbidities identified included elevated BMI > 30 kg/m2 (34.2%), smoking (36.4%), positive allergy testing (43.7%), sleep apnea (38.5%), and esophageal reflux (13.6%). Mental health disorders and posttraumatic stress disorder were likewise common. CONCLUSIONS: Postdeployment pulmonary evaluation should focus on common diseases, such as asthma and airway hyperreactivity, and include testing for upper airway disorders. Diffuse lung diseases were rarely diagnosed, whereas numerous comorbidities were common.

Transudative chylothorax from cirrhosis complicated by lung entrapment.

A patient with long-standing cirrhosis due to hepatitis C and hepatic hydrothorax was evaluated for increasing symptoms and presence of a large right pleural effusion. Thoracentesis revealed evidence of a chylothorax with rapid reaccumulation of pleural fluid. Repeat thoracentesis with manometry identified presence of entrapped lung which complicated treatment options. This is the first case report of a hepatic chylothorax with features of entrapped lung.

Effects of Electrolyte Replacement Protocol Implementation in a Medical Intensive Care Unit.

PURPOSE: To evaluate the effects of electrolyte replacement protocol (ERP) implementation in the medical intensive care unit (MICU) setting. We hypothesized that a protocol would reduce the time of replacement dose administration and increase provider satisfaction with the process of electrolyte replacement. METHODS: This was a retrospective review of electronic medical record data before and after implementation of a standardized ERP in an 18-bed military tertiary care MICU. RESULTS: Median time from abnormal laboratory result to time of documented dose administration for potassium decreased from 180 to 98 minutes ( P < .01), phosphorus decreased from 190 to 135 minutes ( P < .01), calcium decreased from 95 to 61 minutes ( P < .01), and magnesium decreased from 155 to 149 minutes ( P < .01). Overall, there was a significant reduction in time to electrolyte repletion from 146 to 98 minutes ( P < .01) for all electrolytes. Nursing satisfaction for autonomy, timeliness, effectiveness, and the need to seek orders was all improved ( P < .01), and physicians saved 4.4 minutes/patient/day ( P = .04). CONCLUSIONS: Electrolyte replacement protocols can be safely implemented in the MICU and reduce the time from abnormal laboratory result to electrolyte replacement dose administration. They can improve provider satisfaction and reduce physician time with the process of electrolyte replacement.

Pulmonary Function and Respiratory Health of Military Personnel Before Southwest Asia Deployment.

BACKGROUND: Significant concern exists regarding the respiratory health of military personnel deployed to Southwest Asia, given their exposures to numerous environmental hazards. Although the deployed military force is generally assumed to be fit, the pre-deployment respiratory health of these individuals is largely unknown. METHODS: Soldiers deploying to Southwest Asia were recruited from the pre-deployment processing center at Fort Hood, Texas. Participants completed a general and respiratory health questionnaire and performed baseline spirometry. RESULTS: One thousand six hundred ninety-three pre-deployment evaluations were completed. The average age of the participants was 32.2 y, and 83.1% were male. More than one third of surveyed solders had a smoking history, 73% were overweight or obese, and 6.2% reported a history of asthma. Abnormal spirometry was found in 22.3% of participants. Soldiers with abnormal spirometry reported more asthma (10.1% vs 5.1%, P < .001), failed physical fitness tests (9.0% vs 4.6%, P = .02), and respiratory symptoms (32.8% vs 24.3%, P = .001). DISCUSSION: This is the first prospective pre-deployment evaluation of military personnel that delineates factors potentially associated with the development of pulmonary symptoms and/or disease. This study suggests that deploying soldiers are older, heavier, frequently smoke, and may have undiagnosed pre-deployment lung disease. Abnormal spirometry is common but may not represent underlying disease. Self-reported asthma, wheezing, and slower 2-mile run times were predictive of abnormal spirometry. CONCLUSIONS: Pre-deployment evaluation of military personnel identified numerous soldiers with active pulmonary symptoms and abnormal spirometry. When combined with questions regarding asthma history, wheezing and exercise intolerance, spirometry may identify individuals at risk for deployment-related respiratory complaints.