Pneumatic Impedance of Spit Socks and N95 Masks: The Applicability to Death Investigation.

INTRODUCTION: Restrained subjects often spit on law enforcement and corrections officers and medical responders. Based on the droplet-transmitted risk of COVID-19, such spitting could be considered a potentially life-threatening assault. Officers commonly use "spit socks" over the head and neck of spitting subjects to reduce this risk. The pneumatic impedance of such socks has not been published, so this remains an open issue for arrest-related death investigation. METHODS: We purchased samples of 3 popular spit sock models, 3 insect-protecting "bug" socks and hats, 3 N95 masks, a standard 3-ply surgical mask, and a common dust mask. We used a BTmeter model BTN8468 digital anemometer, an HTI model HT-1890 digital manometer, and an AC Infinity Cloudline model S6 inline controllable fan to measure air flow versus pressure drop. We compared the curves graphically and also calculated a pneumatic pseudo-impedance by dividing the pressure drop by the air velocity. RESULTS: The spit and bug socks allowed nearly maximum airflow with minimal pressure (≤1 mm Hg), whereas none of the masks allowed greater than 2 m/s of airflow at maximum pressure of 3 mm Hg. All of the spit and bug masks were grouped together with the lowest pneumatic impedances, whereas all of the N95 masks were grouped together with the highest values. The dust mask and surgical mask were in between with the dust mask closer to the spit and bug masks, whereas the surgical mask was closer to the N95 masks in impedance. CONCLUSIONS: Commonly used spit socks offer nearly zero resistance to breathing. The highest resistance spit sock was still 100 times better than the best N95 mask for airflow during inhalation. Our results do not support the occasional hypothesis that spit socks might contribute to an arrest-related death.

Electrical weapons and excited delirium: shocks, stress, and serum serotonin.

It has been suggested that a CEW (conducted electrical weapon) exposure could elicit a stress response that could cause ExDS (excited delirium syndrome). There are some parallels between the signs of ExDS and serotonin syndrome (SS). Electroconvulsive therapy raises serotonin levels and therefore provides a plausible link between CEW applications and elevated serotonin levels. This study was designed to determine whether a CEW exposure elevates serum serotonin. A total of 31 police academy cadets were exposed to a very broad-spread 5-s CEW stimulus from a TASER brand X26 CEW. Blood was drawn before and after the exposure and at 24 h post exposure to measure serum serotonin levels. Lactic acid and cortisol levels were also compared. Median serum serotonin levels were 30 IQR (21,46), 36 IQR (22,50), and 32 IQR (21,45) ng/mL before exposure, after exposure, and 24 h after exposure (NS by pooled comparisons). The increase from baseline to post-test serotonin (∆ median = +6, ∆ mean = +2.7) ng/mL was not significant by a paired T-test (p = .29) but was significant by the Wilcoxon signed-rank test (p = .037). The increase to post-test log serotonin was not significant by a paired T-test (p = .13) but was significant by the Wilcoxon test (p = .049). All serotonin levels remained within the normal reference range of 0-200 ng/mL. Post-hoc analysis demonstrated that the study was powered to detect a ½ SD change, in log serotonin, with a 90% likelihood. With a very-broad electrode spread, CEW exposure did not significantly raise serum serotonin levels.

Use of wearable devices for post-discharge monitoring of ICU patients: a feasibility study.

BACKGROUND: Wearable devices generate signals detecting activity, sleep, and heart rate, all of which could enable detailed and near-continuous characterization of recovery following critical illness. METHODS: To determine the feasibility of using a wrist-worn personal fitness tracker among patients recovering from critical illness, we conducted a prospective observational study of a convenience sample of 50 stable ICU patients. We assessed device wearability, the extent of data capture, sensitivity and specificity for detecting heart rate excursions, and correlations with questionnaire-derived sleep quality measures. RESULTS: Wearable devices were worn over a 24-h period, with excellent capture of data. While specificity for the detection of tachycardia was high (98.8%), sensitivity was low to moderate (69.5%). There was a moderate correlation between wearable-derived sleep duration and questionnaire-derived sleep quality (r = 0.33, P = 0.03). Devices were well-tolerated and demonstrated no degradation in quality of data acquisition over time. CONCLUSIONS: We found that wearable devices could be worn by patients recovering from critical illness and could generate useful data for the majority of patients with little adverse effect. Further development and study are needed to better define and enhance the role of wearables in the monitoring of post-ICU recovery. TRIAL REGISTRATION: Clinicaltrials.gov, NCT02527408.

Stepwise Rostrocaudal Brainstem Anesthesia as a Complication of Local Anesthesia: A Case Report.

Iatrogenic cranial nerve palsies can rarely complicate neurosurgical, oral maxillofacial, and otolaryngological procedures. Among the most serious complications of cranial nerve palsy is upper airway obstruction, which is life threatening. We present a case of multiple cranial nerve palsies evolving rapidly in a rostrocaudal stepwise fashion after infiltration of lidocaine to repair a cerebrospinal fluid leak in a patient postoccipital craniectomy. This led to hypoxic respiratory failure requiring mechanical ventilation before resolving spontaneously. This is the first known case of accidental brainstem anesthesia secondary to lidocaine infiltration at an occipital craniectomy site and serves to caution clinicians who manage similar patients.

Accuracy of a Wrist-Worn Wearable Device for Monitoring Heart Rates in Hospital Inpatients: A Prospective Observational Study.

BACKGROUND: As the sensing capabilities of wearable devices improve, there is increasing interest in their application in medical settings. Capabilities such as heart rate monitoring may be useful in hospitalized patients as a means of enhancing routine monitoring or as part of an early warning system to detect clinical deterioration. OBJECTIVE: To evaluate the accuracy of heart rate monitoring by a personal fitness tracker (PFT) among hospital inpatients. METHODS: We conducted a prospective observational study of 50 stable patients in the intensive care unit who each completed 24 hours of heart rate monitoring using a wrist-worn PFT. Accuracy of heart rate recordings was compared with gold standard measurements derived from continuous electrocardiographic (cECG) monitoring. The accuracy of heart rates measured by pulse oximetry (Spo2.R) was also measured as a positive control. RESULTS: On a per-patient basis, PFT-derived heart rate values were slightly lower than those derived from cECG monitoring (average bias of -1.14 beats per minute [bpm], with limits of agreement of 24 bpm). By comparison, Spo2.R recordings produced more accurate values (average bias of +0.15 bpm, limits of agreement of 13 bpm, P<.001 as compared with PFT). Personal fitness tracker device performance was significantly better in patients in sinus rhythm than in those who were not (average bias -0.99 bpm vs -5.02 bpm, P=.02). CONCLUSIONS: Personal fitness tracker-derived heart rates were slightly lower than those derived from cECG monitoring in real-world testing and not as accurate as Spo2.R-derived heart rates. Performance was worse among patients who were not in sinus rhythm. Further clinical evaluation is indicated to see if PFTs can augment early warning systems in hospitals. TRIAL REGISTRATION: ClinicalTrials.gov NCT02527408; https://clinicaltrials.gov/ct2/show/NCT02527408 (Archived by WebCite at  http://www.webcitation.org/6kOFez3on).

Rare Presentation of Pulmonary Alveolar Proteinosis Causing Acute Respiratory Failure.

Pulmonary alveolar proteinosis (PAP) is a rare condition characterized by dysfunctional alveolar macrophages, which ineffectively clear surfactant and typically cause mild hypoxemia. Characteristic Computed Tomography findings are septal reticulations superimposed on ground-glass opacities in a crazy paving pattern, with a clear juxtaposition between affected and unaffected parenchyma. While traditionally PAP was diagnosed via biopsy, bronchoalveolar lavage (BAL) is usually sufficient; the fluid appears milky, and on microscopic examination there are foamy macrophages with eosinophilic granules and extracellular hyaline material that is Periodic Acid-Schiff positive. Standard therapy is whole lung lavage (WLL), although novel treatments are under development. The case presented is a 55-year-old woman with six months of progressive dyspnea, who developed hypoxemic respiratory failure requiring mechanical ventilation; she had typical findings of PAP on imaging and BAL. WLL was ultimately successful in restoring adequate oxygenation. Respiratory failure of this magnitude is a rare finding in PAP.

Lymphangiosarcoma of the scalp.

BACKGROUND: Lymphangiosarcoma is a rare, aggressive malignancy that originates from the endothelial cells lining lymphatic vessels and carries an extremely poor prognosis. Its clinical and histologic features are often indistinguishable from angiosarcoma. OBJECTIVE: We sought to better characterize the clinical and histologic features of lymphangiosarcoma. METHODS: Case report and review of the literature. RESULTS: A number of immunohistochemical markers, including Von Willebrand factor, Ulex europaeus agglutinin 1, CD31, VEGFR-3, D2-40, Prox-1, can be used to help differentiate lymphatic from vascular tissue. CONCLUSIONS: Recent characterization of several new biologic markers has allowed greater differentiation between these tumors and may provide new therapeutic targets for treatment.

Desquamative interstitial pneumonitis in a healthy non-smoker: A rare diagnosis.

Desquamative interstitial pneumonitis is an interstitial lung disease most commonly associated with smoking. It causes respiratory symptoms including indolent cough and dyspnea. Characteristic findings on computed tomography include bilateral ground-glass opacities, septal thickening and preserved structure. Diagnosis is made by tissue sampling, which classically demonstrates alveolar macrophages, and thickened alveolar septa with an eosinophilic infiltrate lined with hyperplastic type II pneumocytes. Treatment is immune suppression with steroids or other agents, and avoiding the causal agent. The case reported describes a 27-year-old woman with no smoking history who worked in a potato chip factory, presenting with cough, dyspnea and dizziness. The patient had characteristic findings on imaging and was diagnosed via biopsy with desquamative interstitial pneumonitis. She improved clinically with reduced exposure and steroid therapy. While food production workers are at risk for respiratory illness, there are no reported cases of desquamative interstitial pneumonitis in this setting.

Pulmonary blastomycosis in a professional diver: an occupational risk.

In certain parts of the United States and Canada, and northern Ontario in particular, the dimorphic fungus Blastomyces dermatitidis is endemic and can cause infection in exposed individuals. The site of infection is usually pulmonary, causing respiratory and constitutional symptoms, but can also affect other sites in the body. Symptom severity can vary substantially from no symptoms to fatal acute respiratory distress syndrome. The present report describes a 27-year-old professional diver who had recently worked in northern Ontario, who developed symptoms of pneumonia and exhibited atypical findings on chest imaging. He was diagnosed with blastomycosis based on histopathological findings and fungal culture, and was treated with amphotericin B and itraconazole in accordance with treatment guidelines. While outdoor occupations in endemic areas increase the risk of infection, there is no literature specifically identifying professional diving as an occupational risk for blastomycosis.

Cardiac effects of varying pulse charge and polarity of TASER conducted electrical weapons.

The TASER(R) CEW (Conducted Electrical Weapon) is rapidly replacing the club in the English-speaking world for assisting in the arrest of resistant subjects and is now used by the majority of law enforcement agencies in the USA, Canada, and the UK. Animal safety studies of the CEW have focused on the risk of VF. We sought to determine the difference in cardiac capture and VF risk between the approximately 102 +/- 8 microC of the ubiquitous X26 and a me-tered 72 microC charge from an experimental device. It is well established from the bidomain theory and experimental data that a pacing electrode will capture the heart with significantly lower charge when the electrode touching the cardiac tissue is a cathode However, experimental data show that there is no difference in the ability of the anode vs the cathode to induce VF. We sought to evaluate the effect of polarity changes on cardiac capture and the induction of VF. Small swine ( approximately 20.0 kg) were anesthetized and ventilated. The apex of the heart was located via echocar-diography and a CEW probe was fully inserted towards the apex. Echocardiography was used to monitor cardiac contractions to determine cardiac capture. Both the X26 and the 72 microC pulses were delivered at both polarities to test for cardiac capture. Higher charge pulses (375 microC) were then delivered with both polarities to test for VF risk. The 72 microC experimental unit was unable to cause cardiac capture even in small swine with fully inserted probes directly over the apex of the heart. We found no polarity effect in the risk of VF in small swine with larger charge ( approximately 5x) pulses.