Feltracco P, Serra E, Barbieri S, Persona P, Rea F, Loy M, Ori C. Clin Transplant. 2009 Sep-Oct;23(5):748-50.
This case report described the clinical course of two patients that suffered from refractory hypoxemia caused by the post-reimplantation syndrome treated with NIV in the prone and Trendelenburg positions. The first case report was characterised by a 37-year old woman undergoing bilateral sequential single lung transplant (BSSLT), as a consequence of end stage respiratory failure. She was extubated a few hours after arriving to the ICU and subsequently developed extensive patchy alveolar consolidations in the dorsal and basal regions of the lungs. Due to unresponsive hypoxia, despite the treatment with high oxygen using a face mask, the patient was treated with NIV through respiratory helmet. This approach in conjunction with alternating between the prone and the Trendelenburg positions, improved the patient's condition. Moreover, the implanted lungs were better filled with air and further improvements of oxygenation allowed the removal of the helmet. In the second case, a 44-year-old man with cystic fibrosis underwent BSSLT due to end-stage respiratory failure. Several hours after arriving in the ICU the patient was extubated, but due to increased oxygen desaturation he was treated with facemask delivered NIV. His gas exchange deteriorated as a consequence of lung infiltrations and atelectasis of the lower lobes. Similar to the first case, the implementation of the mask NIV delivery and change in position lead to the improvement of the patient's condition. Therefore, the results from these two case studies show that the use of helmet or facemask NIV in conjunction with position changes represents a valuable approach in patients that have undergone lung transplantation.
Link to abstract
Park MH, Kim MJ, Kim AJ, Lee MJ, Kim JS. World J Clin Cases. 2020;8(10):1939-1943.
This report described a case of a 73-year-old man with COPD (stage 4) admitted to the ICU with complaints of cough, sputum, and dyspnoea. The patient was previously treated with oxygen at home for 10 months during the day time and oronasal mask-based NIV during night time. At the time of admission, the infection was detected and infiltration was also present. He was subsequently diagnosed with AECOPD by community-acquired pneumonia. Conditions deteriorated and invasive ventilation became unavoidable. However, helmet-based NIV was chosen as the patient refused to proceed with the invasive procedure. After three days of helmet NIV, he regained consciousness and hypercapnia recovered to pre-hospitalisation levels. This report demonstrates that helmet-based NIV may be a crucial treatment strategy used to treat patients with AECOPD that refuse invasive approaches and oronasal mask-based NIV is non-effective.
Link to abstract.
Longhini F, Liu L, Pan C, et al. Respir Care. 2019;64(5):582-589
In this study compared neurally-controlled pressure support through a helmet with pressure support through a face mask for subject comfort, breathing pattern, gas exchange, pressurization and triggering performance, and patient-ventilator synchrony. Two 30-min trials of NIV were randomly delivered to 10 subjects with COPD exacerbation. The first group was treated with pressure support through a face mask and the second group with NAVA through a helmet. Several parameters were evaluated including subject comfort, breathing frequency, respiratory drive, arterial blood gases, pressure-time product (PTP) of the first 300 ms and 500ms after initiation of subject effort, inspiratory trigger delay, and rate of asynchrony determined as the asynchrony index. NAVA through a helmet significantly improved comfort compared with pressure support through a face mask. Although the breathing pattern was not different between the methods, the respiratory drive was slightly reduced during NAVA through a helmet in comparison with pressure support through a face mask. Gas exchange was also not different between the trials. The PTP was comparable between trials, whereas triggering performance, patient-ventilator interaction, and synchrony were all improved by NAVA through a helmet compared with pressure support through a face mask. Therefore, in subjects with COPD with exacerbation, NAVA through a helmet improved comfort, triggering performance, and patient-ventilator synchrony compared with pressure support through a face mask.
Link to abstract
Ferioli M, Cisternino C, Leo V, Pisani L, Palange P, Nava S. Eur Respir Rev. 2020 Apr 3;29(155):200068
The objective of this paper is to provide evidence-based recommendations for the correct use of respiratory devices in the COVID-19 emergency and protect healthcare workers from contracting the SARS-CoV-2 infection. Current evidence shows that around 20% of COVID-19 patients develop a severe Respiratory Distress Syndrome, which in almost a third of the cases requires respiratory support treatment. This type of support includes the use of oxygen therapy, HFNC, CPAP and NIV, which are non-invasive methods with a high risk of aerosol dispersion, especially in unprotected environments. Amongst those methods of delivery of non-invasive respiratory support, the use of a respiratory helmet with an inflatable neck cushion represents the safest option. In addition, data suggest that respecting the indications for the use of PPE is effective in preventing infections among healthcare workers, as demonstrated in a case–control study conducted during the SARS epidemic in Hong Kong. This study investigated the effective adhesion of personnel to PPE (gloves, disposable shirts, goggles and masks) and reported that none of the staff using all the safety measures contracted the virus, while all the infected staff had omitted at least one of them. Therefore, the helmet with neck cushion to treat infected patients with severe respiratory distress syndrome and PPE measures by the personnel must be adopted to prevent the spreading of infection amongst other patients and medical personnel.
Link to abstract.
Hui DS, Chow BK, Lo T, Ng SS, Ko FW, Gin T, Chan MTV. Chest. 2015 May;147(5):1336-1343.
This study set out to determine the extent of exhaled air dispersion, which is linked to the rate of nosocomial infections, when employing NIV using a high-fidelity human patient simulator. Two different helmets and one face mask were put to the test, which included the Sea-Long Medical Systems helmet, the StarMed CaStar R helmet and a Koninklijke Philips total facemask. Exhaled air was evaluated in a negative pressure room with 12 air changes/h by two different helmets via a ventilator and a total facemask via a bilevel positive airway pressure device. Exhaled air was labelled by intrapulmonary smoke particles, illuminated by laser light sheet, and captured through a camera for data analysis. Results have demonstrated that during NIV via the Sea-Long Medical Systems helmet, exhaled air leaked through the neck seal reaching a radial distance of 150 to 230 mm. The patient simulator was programmed for mild lung injury and treated with inspiratory positive airway pressure from 12 to 20cm/H2O respectively and with expiratory pressure of 10cm/H2O. However, when delivering NIV via a StarMed CaStar R helmet with air cushion around the neck, air leakage was negligible. On the other hand, when administering NIV via a total face mask, air leaked through the exhalation port to a distance of 618 and 812 mm when inspiratory pressure was increased from 10 to 18 cm H2O, with the expiratory pressure at 5cm H2O. Therefore, using the helmet with a good seal around the neck represents the best option to prevent nosocomial infection during NIV for patients with respiratory infections.
Link to abstract.