Use of High Velocity Therapy at a Critical Access Hospital in the Early Management of a Patient Presenting with Acute Exacerbation of Chronic Obstructive Pulmonary Disease

Jean Applegate, Cardiopulmonary Manager • Dr. Demosthenes Asuncion, E.D. Medical Director
Pana Community Hospital

Vapotherm does not practice medicine or provide medical services or advice. Vapotherm’s high velocity therapy is a tool for treating respiratory distress. Although individual results may vary, Vapotherm believes this case study is an example of the clinical benefit Vapotherm’s high velocity therapy can have in a Critical Access Hospital Setting.

Introduction
Management of respiratory distress associated with Acute Exacerbation of Chronic Obstructive Pulmonary Disease (COPD) is a frequent challenge in the Emergency Department (ED). According to a recent study, 29% of COPD patients frequently present to the hospital for management of AECOPD, and that this 29% accounted for 64% of mechanical ventilation use, and 55% of the total charges for ED and inpatient utilization. [1]

Patient History and Presentation
A 64 year-old male presented to the Emergency Department (ED) via private vehicle with a chief complaint of shortness of breath. He has a history of severe COPD with frequent exacerbations, oxygen dependency and pulmonary nodules. He had been admitted one week prior to presentation for acute exacerbation of COPD (AECOPD), resulting in a 2 day hospital stay. Upon arrival, he was in acute respiratory distress with severe retractions, displaying ‘tripod’ positioning, pallor, tachypnea, and was unable to speak more than 1-2 words at a time. The patient had an initial pulse oxygen saturation (SpO2) of 78% on 2 LŸmin-1 via nasal cannula (NC).

Treatment and Response
Initially, the patient received 3 successive aerosolized medication breathing treatments via O2 driven jet neb with ipratropium bromide and albuterol sulfate in an attempt to relieve his acute dyspnea. Arterial blood gases (ABGs) were drawn while receiving a breathing treatment and revealed a pH of 7.27, PaCO2 of 74 mmHg and a PaO2 of 110 mmHg on 2 LŸmin-1 via NC. These results lead the ED physician to immediately order non-invasive positive pressure ventilation (NIPPV). After consultation with the ED physician, it was determined that this patient was a good candidate for high velocity therapy.

The patient was placed on high velocity therapy (Precision Flow, Vapotherm, Exeter, NH: Adult cannula with a 2.7 mm I.D.) at 40 LŸmin-1 and FiO2 = 0.60.  Within 10 minutes of initiation of therapy, the patient was able to speak longer sentences, drink water, his color had improved, and SpO2 readings were between 98-100%.  The FiO2 was reduced to 0.40.

Twenty minutes after application of the therapy, the patient’s respiratory rate had dropped from above 30 breaths per minute (BPM) to 14 BPM, and SpO2 remained between 98-100%.   The FiO2 was subsequently reduced to 0.28.

Another ABG was drawn one hour after initiation of high velocity therapy, resulting with pH 7.37, PaCO2 = 52.9 mmHg and PaO2 = 70.2 mmHg.  He was eupneic with normal speech and good color.  Rather than being placed on NiPPV and being transferred to a tertiary care facility due to his respiratory distress, he was admitted to the Med/Surg floor of the Critical Access facility on high velocity therapy.  Over the course of the next 2 days, the flow rate on the Vapotherm was weaned down.  He was subsequently set up with nocturnal bi-level positive airway pressure, placed back on his home setting of nasal oxygen at 2 L/min and referred to a pulmonologist for management post discharge.

Discussion
Management of respiratory distress presenting in the Critical Access Hospital presents challenges. In addition to the clinical management issues of the rapid management of respiratory decompensation, the practical aspects of patient stabilization and subsequent care become important. In many smaller hospitals, without specific intensive care facilities capable of management of ‘advanced’ respiratory modalities, initiation of NIPPV necessitates transfer to another acute care facility. This transfer is technically problematic, expensive, and has a significant impact on the ability of local family visiting and participation in the patient-care process. The transfer also has substantial financial challenges for the originating hospital after the transfer.

The presenting hospital, Pana Community Hospital, in this case report is a Critical Access Hospital (CAH) located in central Illinois and is a member of the Illinois Critical Access Hospital Network (ICAHN).  The CAH designation is designed to reduce the financial vulnerability of rural hospitals and improve access to healthcare by keeping essential services local to those communities.  Eligible hospitals must meet certain conditions to obtain the CAH designation, including having 25 or fewer acute care beds, be located more than 35 miles from another hospital, maintain an annual average length of stay of 96 hours or less for acute care patients, and provide 24/7 emergency care services.  In a rural setting, staffing and resources for 24/7 emergency care can be a challenge.  However, the provision of these community services is important, and the maintenance of patient presence is of both patient and institutional importance.

This report describes the successful intervention of high velocity therapy in the management of a patient with known-etiology acute respiratory distress (hypercarbic chronic obstructive pulmonary disease). The patient presented with substantial hypercapnia, uncontrolled by oxygen therapy alone. The ability to provide management for patients presenting with both Type 1 and Type 2 Respiratory failure is an important feature of successful non-invasive ventilatory support.

NIPPV is the current medical technology standard of care used in emergent management of such patients, with efficacy having been demonstrated for important presenting conditions. [2][3] NIPPV is associated with known patient comfort issues, as well as attendant risk of both hemodynamic compromise and barotrauma. [4]

High velocity therapy delivers high flows of optimally conditioned medical gas at high velocities. The high velocity inflow of gas facilitates rapid flush of the accessible extrathoracic dead space by increasing turbulent kinetic energy. [5] This ventilatory support using rapid flush via high velocity is further facilitated by the provision of inspiratory flow augmentation, heated humidified gas facilitating ventilation, reduction in metabolic cost to heat and condition gas, and the provision of mild distending pressure. [6] Doshi, et al. [7], described the utility of high velocity therapy in the management of undifferentiated respiratory failure presenting in the ED requiring NiPPV. High velocity therapy was employed in the study and demonstrated non-inferiority to NiPPV for both all-cause failure and failure requiring intubation. Comparable clinical efficacy with an open nasal cannula-based interface presents clinical management advantages. The open interface and the user-friendly operation may permit acutely ill patients to be managed in settings which would otherwise not tolerate the support of patients on NIPPV.

The early implementation of high velocity therapy helped provide adequate ventilatory support for this AECOPD patient and permitted management of the patient at the level of the Critical Access Hospital, without necessity to transport to another acute care facility.

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