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1.
BMC Pediatr ; 23(Suppl 2): 569, 2023 11 15.
Article in English | MEDLINE | ID: mdl-37968578

ABSTRACT

BACKGROUND: Millions of newborns die annually from preventable causes, with the highest rates occurring in Africa. Reducing neonatal mortality requires investment to scale hospital care, which includes providing hospitals with appropriate technology to care for small and sick newborns. Expensive medical devices designed for high-resource settings often fail to withstand conditions in low-resource hospitals, including humidity, dust, frequent user turnover, complex maintenance, lack of stable power, or difficulty sourcing expensive consumables. Rigorous evaluation protocols are needed to identify effective, affordable, rugged, and easy-to-use medical devices appropriate for quality hospital-based newborn care in low-resource hospitals. METHODS: We developed an evidence-based technology review process to identify medical devices suitable for small and sick newborn care in low-resource hospitals. The eight-step process consists of: identifying devices needed for effective newborn care; defining Target Product Profiles (TPPs); identifying commercially-available products that may meet TPPs; conducting desk research to evaluate technologies against TPPs; performing technical performance verification testing under laboratory conditions; verifying technical performance after exposure to heat, humidity, dust, and power loss; performing usability evaluations with nurses, and qualifying devices that pass all steps. Devices were purchased, installed, and monitored in newborn wards across Kenya, Malawi, Nigeria, and Tanzania. RESULTS: Of 271 devices considered, only 45 (16.6%) met corresponding TPPs based on desk research. Thirty-nine were purchased and evaluated in the laboratory; five (12.8%) failed to meet TPPs. Thirty-four products passing laboratory evaluation underwent short-term environmental testing; only one (2.9%) device failed. Thirty-seven products underwent usability testing with 127 clinicians; surprisingly, 14 (37.8%) failed to meet TPPs. Twenty-three products passed all evaluations, and 2457 devices were installed across 65 newborn wards in Kenya, Malawi, Nigeria, and Tanzania. Continuous device monitoring reported minimal device failures, with failed devices typically returned to service within two days, resulting in an average uptime (service days divided by days installed) of 99%. CONCLUSION: An evidence-based device selection process can improve procurement of effective, affordable, rugged, usable newborn care devices for low-resource hospitals, and feedback to manufacturers can improve device quality. Similar processes could be adapted beyond newborn care to identify medical devices suitable for implementation in any low-resource setting.


Subject(s)
Cemeteries , Hospitals , Infant, Newborn , Humans , Infant Mortality , Kenya , Dust
2.
BMC Pediatr ; 23(Suppl 2): 564, 2023 11 15.
Article in English | MEDLINE | ID: mdl-37968603

ABSTRACT

BACKGROUND: Medical devices are critical to providing high-quality, hospital-based newborn care, yet many of these devices are unavailable in low- and middle-income countries (LMIC) and are not designed to be suitable for these settings. Target Product Profiles (TPPs) are often utilised at an early stage in the medical device development process to enable user-defined performance characteristics for a given setting. TPPs can also be applied to assess the profile and match of existing devices for a given context. METHODS: We developed initial TPPs for 15 newborn product categories for LMIC settings. A Delphi-like process was used to develop the TPPs. Respondents completed an online survey where they scored their level of agreement with each of the proposed performance characteristics for each of the 15 devices. Characteristics with < 75% agreement between respondents were discussed and voted on using Mentimeter™ at an in-person consensus meeting. FINDINGS: The TPP online survey was sent to 180 people, of which 103 responded (57%). The majority of respondents were implementers/clinicians (51%, 53/103), with 50% (52/103) from LMIC. Across the 15 TPPs, 403 (60%) of the 668 performance characteristics did not achieve > 75% agreement. Areas of disagreement were voted on by 69 participants at an in-person consensus meeting, with consensus achieved for 648 (97%) performance characteristics. Only 20 (3%) performance characteristics did not achieve consensus, most (15/20) relating to quality management systems. UNICEF published the 15 TPPs in April 2020, accompanied by a report detailing the online survey results and consensus meeting discussion, which has been viewed 7,039 times (as of January 2023). CONCLUSIONS: These 15 TPPs can inform developers and enable implementers to select neonatal care products for LMIC. Over 2,400 medical devices and diagnostics meeting these TPPs have been installed in 65 hospitals in Nigeria, Tanzania, Kenya, and Malawi through the NEST360 Alliance. Twenty-three medical devices identified and qualified by NEST360 meet nearly all performance characteristics across 11 of the 15 TPPs. Eight of the 23 qualified medical devices are available in the UNICEF Supply Catalogue. Some developers have adjusted their technologies to meet these TPPs. There is potential to adapt the TPP process beyond newborn care.


Subject(s)
United Nations , Infant, Newborn , Humans , Kenya , Malawi , Nigeria , Tanzania
3.
PLoS One ; 15(12): e0242590, 2020.
Article in English | MEDLINE | ID: mdl-33270660

ABSTRACT

Respiratory distress due to preterm birth is a significant cause of death in low-resource settings. The introduction of continuous positive airway pressure (CPAP) systems to treat respiratory distress significantly reduced mortality in high-resource settings, but CPAP was only recently introduced in low-resource settings due to cost and infrastructure limitations. We evaluated pressure stability and imposed work of breathing (iWOB) of five CPAP systems used in low resource settings: the Fisher and Paykel bubble CPAP, the Diamedica baby CPAP, the Medijet nCPAP generator, and the first (2015) and second (2017) generation commercially available Pumani CPAPs. Pressure changes due to fresh gas flow were evaluated for each system by examining the relationship between flow and pressure at the patient interface for four pressures generated at the bottle (0, 3, 5, and 7 cm H2O); for the Medijet nCPAP generator, no bottle was used. The slope of the resulting relationship was used to calculate system resistance. Poiseuille's law of resistance was used to investigate significant contributors to resistance. Resistance ranged from 0.05 to 1.40 [Formula: see text]; three CPAP devices had resistances < 0.4 [Formula: see text]: the Fisher and Paykel system, the Diamedica system, and the second generation Pumani bubble CPAP. The other two systems, the Medijet nCPAP generator and the first generation Pumani bCPAP, had resistances >1.0 [Formula: see text]. Imposed WOB was measured using an ASL5000 test lung to simulate the breath cycle for an infant (5.5 kg), a term neonate (4.0 kg), and a preterm neonate (2.5 kg). Imposed WOB ranged from 1.4 to 39.5 mJ/breath across all systems and simulated infant sizes. Changes in pressure generated by fresh gas flow, resistance, and iWOB differ between the five systems evaluated under ideal laboratory conditions. The available literature does not indicate that these differences affect clinical outcomes.


Subject(s)
Continuous Positive Airway Pressure , Health Resources , Work of Breathing , Gases , Humans , Pressure , Rheology
4.
BMJ Paediatr Open ; 4(1): e000655, 2020.
Article in English | MEDLINE | ID: mdl-32426530

ABSTRACT

OBJECTIVE: Evaluate a novel continuous temperature monitor in a low-resource neonatal ward. DESIGN: We developed a low-cost continuous neonatal temperature monitor (NTM) for use in low-resource settings. Accuracy of NTM was initially assessed in the laboratory. Clinical evaluation then was performed in a neonatal ward in a central hospital in Malawi; eligible neonates (<1 week of age) were recruited for continuous temperature monitoring with NTM and a Philips Intellivue MP30 Patient Monitor. INTERVENTIONS AND OUTCOME MEASURES: The temperature probes of NTM and the reference patient monitor were attached to the infant's abdomen, and core temperature was continuously recorded for up to 3 hours. Axillary temperatures were taken every hour. We compared temperatures measured using NTM, the patient monitor and the axillary thermometer. RESULTS: Laboratory temperature measurements obtained with NTM were within 0.059°C (range: -0.035°C to 0.195°C) of a reference thermometer. A total of 39 patients were recruited to participate in the clinical evaluation of NTM; data from four patients were excluded due to faulty hardware connections. The mean difference in measured temperatures between the NTM and the Intellivue MP30 was -0.04°C (95% CI -0.52°C to 0.44°C). CONCLUSION: NTM meets ISO 80601-2-56 standards for accuracy and is an appropriate, low-cost continuous temperature monitor for neonatal wards in low-resource settings. TRIAL REGISTRATION NUMBERS: NCT03965312 and NCT03866122.

5.
J Neuroeng Rehabil ; 11: 170, 2014 Dec 19.
Article in English | MEDLINE | ID: mdl-25526770

ABSTRACT

BACKGROUND: Intention tremor and dysmetria are leading causes of upper extremity disability in Multiple Sclerosis (MS). The development of effective therapies to reduce tremor and dysmetria is hampered by insufficient understanding of how the distributed, multi-focal lesions associated with MS impact sensorimotor control in the brain. Here we describe a systems-level approach to characterizing sensorimotor control and use this approach to examine how sensory and motor processes are differentially impacted by MS. METHODS: Eight subjects with MS and eight age- and gender-matched healthy control subjects performed visually-guided flexion/extension tasks about the elbow to characterize a sensory feedback control model that includes three sensory feedback pathways (one for vision, another for proprioception and a third providing an internal prediction of the sensory consequences of action). The model allows us to characterize impairments in sensory feedback control that contributed to each MS subject's tremor. RESULTS: Models derived from MS subject performance differed from those obtained for control subjects in two ways. First, subjects with MS exhibited markedly increased visual feedback delays, which were uncompensated by internal adaptive mechanisms; stabilization performance in individuals with the longest delays differed most from control subject performance. Second, subjects with MS exhibited misestimates of arm dynamics in a way that was correlated with tremor power. Subject-specific models accurately predicted kinematic performance in a reach and hold task for neurologically-intact control subjects while simulated performance of MS patients had shorter movement intervals and larger endpoint errors than actual subject responses. This difference between simulated and actual performance is consistent with a strategic compensatory trade-off of movement speed for endpoint accuracy. CONCLUSIONS: Our results suggest that tremor and dysmetria may be caused by limitations in the brain's ability to adapt sensory feedback mechanisms to compensate for increases in visual information processing time, as well as by errors in compensatory adaptations of internal estimates of arm dynamics.


Subject(s)
Brain/physiopathology , Feedback, Sensory/physiology , Multiple Sclerosis/physiopathology , Proprioception/physiology , Tremor/physiopathology , Adult , Aged , Female , Humans , Male , Middle Aged , Models, Biological , Movement/physiology , Multiple Sclerosis/complications , Pilot Projects , Tremor/etiology , Young Adult
6.
Article in English | MEDLINE | ID: mdl-25570760

ABSTRACT

Motor control deficits during aging have been well-documented. Various causes of neuromotor decline, including both peripheral and central neurological deficits, have been hypothesized. Here, we use a model of closed-loop sensorimotor control to examine the functional causes of motor control deficits during aging. We recruited 14 subjects aged 19-61 years old to participate in a study in which they performed single-joint compensatory and pursuit tracking tasks with their dominant hand. We found that visual response delay and visual noise increased with age, while reliance on visual feedback, especially during compensatory tracking decreased. Increases in visual noise were also positively correlated with increases in movement error during a reach and hold task. The results suggest an increase in noise within the visuomotor control system may contribute to the decline in motor performance during early aging.


Subject(s)
Aging/physiology , Movement/physiology , Psychomotor Performance/physiology , Sensorimotor Cortex/physiology , Adult , Elbow/physiology , Feedback, Sensory , Female , Humans , Male , Middle Aged , Young Adult
7.
Article in English | MEDLINE | ID: mdl-22256038

ABSTRACT

An ongoing debate in the field of motor control considers how the brain uses sensory information to guide the formation of motor commands to regulate movement accuracy. Recent research has shown that the brain may use visual and proprioceptive information differently for stabilization of limb posture (compensatory movements) and for controlling goal-directed limb trajectory (pursuit movements). Using a series of five experiments and linear systems identification techniques, we modeled and estimated the sensorimotor control parameters that characterize the human motor response to kinematic performance errors during continuous compensatory and pursuit tracking tasks. Our findings further support the idea that pursuit and compensatory movements of the limbs are differentially controlled.


Subject(s)
Movement/physiology , Proprioception/physiology , Pursuit, Smooth/physiology , Visual Perception/physiology , Adult , Female , Humans , Motor Activity/physiology , Robotics , Time Factors
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