Adaptive Manufacturing for Healthcare During the COVID-19 Emergency and Beyond

During the COVID-19 pandemic, global health services have faced unprecedented demands. Many key workers in health and social care have experienced crippling shortages of personal protective equipment, and clinical engineers in hospitals have been severely stretched due to insufficient supplies of medical devices and equipment. Many engineers who normally work in other sectors have been redeployed to address the crisis, and they have rapidly improvised solutions to some of the challenges that emerged, using a combination of low-tech and cutting-edge methods. Much publicity has been given to efforts to design new ventilator systems and the production of 3D-printed face shields, but many other devices and systems have been developed or explored. This paper presents a description of efforts to reverse engineer or redesign critical parts, specifically a manifold for an anaesthesia station, a leak port, plasticware for COVID-19 testing, and a syringe pump lock box. The insights obtained from these projects were used to develop a product lifecycle management system based on Aras Innovator, which could with further work be deployed to facilitate future rapid response manufacturing of bespoke hardware for healthcare. The lessons learned could inform plans to exploit distributed manufacturing to secure back-up supply chains for future emergency situations. If applied generally, the concept of distributed manufacturing could give rise to "21st century cottage industries" or "nanofactories," where high-tech goods are produced locally in small batches.

A summary of the recommendations for smoking cessation interventions: the quality assurance in the treatment of drug dependence project

This report presents outlines for approaches to smoking cessation. These recommendations are based on a meta-analysis of the treatment-outcome literature, a survey of current treatment practices and the views of a panel of experts. Face-to-face intervention to assist smokers to stop smoking needs to be considered in the context of a public policy approach to reducing the prevalence of smoking. The nature of face-to-face interventions is determined by the time available to practitioners. Where there is no time to intervene (e.g. in some primary health care settings) quality self-help materials should be prominently displayed. Where there is only 10 minutes or less, attention should be focused on personalizing the health effects of smoking, providing firm advice to quit, providing self-help material, setting a quit date (if appropriate), identifying social support for cessation and organizing a follow-up visit. If there is more time to intervene (up to one hour) the previous techniques can be expanded on and supplemented with nicotine replacement and discussion of methods for dealing with high-risk situations. Longer interventions would use all of these methods, presenting them in more detail, and may also address stress management and minimization of weight gain.

Hypoglycemia alarm enhancement using data fusion

BACKGROUND

The acceptance of closed-loop blood glucose (BG) control using continuous glucose monitoring systems (CGMS) is likely to improve with enhanced performance of their integral hypoglycemia alarms. This article presents an in silico analysis (based on clinical data) of a modeled CGMS alarm system with trained thresholds on type 1 diabetes mellitus (T1DM) patients that is augmented by sensor fusion from a prototype hypoglycemia alarm system (HypoMon). This prototype alarm system is based on largely independent autonomic nervous system (ANS) response features.

METHODS

Alarm performance was modeled using overnight BG profiles recorded previously on 98 T1DM volunteers. These data included the corresponding ANS response features detected by HypoMon (AiMedics Pty. Ltd.) systems. CGMS data and alarms were simulated by applying a probabilistic model to these overnight BG profiles. The probabilistic model developed used a mean response delay of 7.1 minutes, measurement error offsets on each sample of +/- standard deviation (SD) = 4.5 mg/dl (0.25 mmol/liter), and vertical shifts (calibration offsets) of +/- SD = 19.8 mg/dl (1.1 mmol/liter). Modeling produced 90 to 100 simulated measurements per patient. Alarm systems for all analyses were optimized on a training set of 46 patients and evaluated on the test set of 56 patients. The split between the sets was based on enrollment dates. Optimization was based on detection accuracy but not time to detection for these analyses. The contribution of this form of data fusion to hypoglycemia alarm performance was evaluated by comparing the performance of the trained CGMS and fused data algorithms on the test set under the same evaluation conditions.

RESULTS

The simulated addition of HypoMon data produced an improvement in CGMS hypoglycemia alarm performance of 10% at equal specificity. Sensitivity improved from 87% (CGMS as stand-alone measurement) to 97% for the enhanced alarm system. Specificity was maintained constant at 85%. Positive predictive values on the test set improved from 61 to 66% with negative predictive values improving from 96 to 99%. These enhancements were stable within sensitivity analyses. Sensitivity analyses also suggested larger performance increases at lower CGMS alarm performance levels.

CONCLUSION

Autonomic nervous system response features provide complementary information suitable for fusion with CGMS data to enhance nocturnal hypoglycemia alarms.

Continuous vs intermittent albuterol, at high and low doses, in the treatment of severe acute asthma in adults

Adult patients suffering from acute asthma presenting to the Emergency Department with an FEV1 of less than 40% of predicted were randomized into four treatment groups. They were treated with nebulized albuterol at a high (7.5 mg) or standard (2.5 mg) dose given either continuously through 1 h, or intermittently every hour, for 2 h. When the FEV1 improvements for the different groups at 2 h were compared, the groups treated with continuous nebulization had the greatest improvement. The improvements (1.07 L for the high-dose group, and 1.02 L for the standard-dose group) were significantly greater than the improvement seen with standard-dose intermittent treatment (0.72 L; p < 0.05). The improvement in FEV1 of the high-dose, hourly treated group was intermediate in magnitude between these (0.09 L). There was no difference in the improvement seen between the two groups treated with continuous nebulization. The potassium fall, present in all groups, was more pronounced in the groups treated with high doses of albuterol. Only one person (high dose, continuous treatment group) developed hypokalemia of less than 3.0 mmol/L. The high-dose hourly treated group had the highest incidence of side effects, and the standard-dose continuously treated group had the lowest. The standard-dose continuous-treatment regimen had the greatest improvement in FEV1 with the least number of side effects.

Isoetharine versus albuterol for acute asthma: greater immediate effect, but more side effects

PURPOSE

To compare the magnitudes of the immediate effects of the nebulized beta-agonists isoetharine and albuterol in the treatment of acute severe asthma.

PATIENTS AND METHODS

Fifty-one adults presenting with severe asthma exacerbations (forced expiratory volumes in the first second of exhalation [FEV1] <40% of predicted) to the emergency department were randomized (double-blind) to receive hourly inhaled nebulization treatment with either isoetharine (5 mg) or albuterol (2.5 mg). The FEV1 was measured immediately before and after each nebulized treatment. Any side effects were recorded.

RESULTS

Immediately after the first nebulized treatment, the isoetharine group improved its mean FEV1 (+/-SEM) by a significantly greater amount than did the albuterol group: 60% +/- 11% versus 39% +/- 5%, respectively (P <0.05). One hour later the mean FEV1 were equivalent. This pattern repeated itself after the second hourly treatment. The two groups did not differ in any outcome parameters (FEV1 at discharge, number of nebulized treatments required, the number of inpatient admissions, number of clinical relapses after discharge). More patients treated with isoetharine had side effects (36% versus 4% for albuterol, P <0.01), 1 of whom required discontinuation from the study.

CONCLUSIONS

Both medications were equally effective in alleviating bronchospasm. The immediate effect of isoetharine was significantly greater, but equalized that of albuterol within an hour after treatment. There were more side effects with isoetharine.

The pros and cons of transdermal nicotine therapy

OBJECTIVE

To review current knowledge of the efficacy, safety and cost of transdermal nicotine therapy for smoking cessation.

DATA SOURCES AND STUDY SELECTION

1. Published and unpublished reports of randomised, double-blind trials of at least 12 weeks' duration, in smokers motivated to cease smoking, identified by a search of the MEDLINE database, article and book bibliographies, Current contents, and by a request to the Medical Department of Ciba-Geigy (Australia) Ltd. 2. A clinical trial of 1500 smokers using transdermal nicotine (S Gourlay, unpublished data).

DATA SYNTHESIS

Transdermal nicotine more than doubles the success rates of smoking cessation attempts in motivated subjects who smoke at least 10-15 cigarettes per day (odds ratio 12 months after quitting, 2.3; 95% confidence interval, 1.6-3.4). Application site reactions are not uncommon (erythema or burning < or = 16%, transient itch < or = 50%) and cause discontinuation of therapy in up to 10% of subjects. Sleep disturbance due to nocturnal nicotine absorption occurs in up to 13% of subjects when patches are worn overnight. Smoking or nicotine chewing gum used concurrently with transdermal nicotine could raise peak nicotine levels but is unlikely to adversely affect individuals with established tolerance to nicotine. Smoking and (theoretically) nicotine replacement therapies should be avoided in pregnancy or patients with unstable coronary artery disease. In such patients, the risk-benefit ratio of nicotine replacement therapies may be favourable for nicotine-dependent smokers unable to cease smoking by alternative methods.

CONCLUSIONS

Transdermal nicotine is an effective smoking cessation therapy for motivated, nicotine-dependent smokers. As most smokers can cease smoking on their own, and the patches are costly, they should be recommended only for smokers who are unable to quit by simpler means and those likely to suffer severe nicotine withdrawal symptoms.

A placebo-controlled study of three clonidine doses for smoking cessation

BACKGROUND AND OBJECTIVE

Clonidine in doses of 150 to 450 micrograms per day has been reported to reduce symptoms of craving associated with tobacco withdrawal and, in some cases, to improve long-term abstinence rates of smoking cessation programs. However, subjects frequently experienced symptoms of dry mouth and drowsiness. This study investigated the lower end of the effective dose range of clonidine for smoking cessation to identify the lowest useful dose and thus minimize the adverse effects of the drug.

METHODS

A randomized, double-blind, four-way crossover design compared the effects of clonidine doses or placebo within individual subjects for 4 consecutive weeks. Smokers who were highly nicotine dependent were randomly assigned to different sequences of placebo and 300, 200, and 100 micrograms clonidine per day. Subjects were treated for 4 days of each treatment week and began smoking cessation from the end of day 2. Smokers recorded withdrawal symptoms on multiple visual analog scales during days 3 and 4 before resuming normal smoking until the next period of smoking cessation.

RESULTS

A statistically significant dose-response effect was found for craving scores (dose-response gradient, -3.8/100 micrograms; 95% confidence interval [CI], -6.2 to -1.5; p = 0.002) but not for pooled tobacco withdrawal scores. The dose of 300 micrograms per day reduced mean craving scores significantly (-16%; 95% CI, -31% to -1%). Dosing with 200 micrograms approached statistical significance (-14%; 95% CI -30% to 1%) but dosing with 100 micrograms did not (-6%; 95% CI, -22% to 9%). Troublesome adverse experiences were reported by more than 67% of subjects during 200 and 300 micrograms dosing.

CONCLUSIONS

This study showed a statistically significant dose-response effect of clonidine on tobacco withdrawal craving and a reduction in mean craving scores of 16% during 300 micrograms dosing. However, its clinical usefulness is doubtful because of frequently reported adverse experiences.

Differences in the acute and chronic antihypertensive effects of lisinopril and enalapril assessed by ambulatory blood pressure monitoring

Although lisinopril and enalapril are equipotent angiotensin converting enzyme (ACE) inhibitors lisinopril has been reported to produce greater inhibition of plasma ACE 24 hours after single doses. This study compared the antihypertensive effects of once daily 10mg doses of the drugs using a randomised, double-blind, two period cross-over design with ambulatory blood pressure monitoring. Lisinopril lowered mean 24 hour systolic blood pressure significantly more than enalapril after 4 weeks of treatment (14/7 +/- 2/1mmHg & 9/6 +/- 2/1mmHg, respectively, adjusted SBP difference 4.8mmHg, P < 0.01). This difference was confined to the second 12 hours of the daily dosage interval (adjusted SBP difference 13-24 hours after dosing 9.9mmHg, P < 0.001). The diastolic pressure showed a similar trend but this was not statistically significant. The side effects of each agent were minor. We conclude that chronic, once daily therapy with 10mg of lisinopril reduces systolic blood pressure more effectively than an equal dose of enalapril due to its greater effect in the latter half of the 24 hour dosage interval.

Optical mapping of the thoracoabdominal wall

An optical technique has been developed for mapping the size and shape of the thoracoabdominal wall and the change in its shape with breathing. A fixed pattern composed of stripes of light is projected on to both sides of the trunk. These stripes become distorted when viewed from in front and behind, forming contours over the trunk surface. The contours are photographed and then encoded digitally. The digital information can be used to compute automatically the volume of the trunk, the position of any point on its surface, and its cross sectional shape at any level. The technique has been tested on rigid objects (a globe, a cone, and two dummy torsos) that can be measured precisely. With this optical technique linear dimensions can be calculated to within 0.5 mm, cross sectional area to within 5%, and volume to within 1.6-3.7%. These results suggest that this non-invasive technique measures the shape and volume of complex three dimensional surfaces with sufficient accuracy to be tried in clinical practice.