Low-flow Nasal Cannula Research Articles

The Effects of Low flow Nasal Cannula Oxygen-therapy during The Low Intensity Exercise Intervention on The gait improvement of old patient with Thoracic Vertebral Fracture and Respiratory Disease

Purpose: In this case study, we aimed to examine the effects of low-flow nasal oxygen therapy during a low-intensity exercise intervention on the gait improvement of a patient with thoracic vertebral fracture and respiratory disease. Methods: An old patient with thoracic vertebral fracture and respiratory disease received low-flow nasal oxygen therapy during low-intensity (Borg scale, 3-4) exercises (e.g., tilting table, walker standing, and walker gait) for 4 weeks. Results: We found that the patient could breathe on her own in room air during independent gait with a walker. Conclusion: Low-flow nasal cannula oxygen therapy during a low-intensity exercise intervention improved general weakness and strengthened respiratory muscles as well as shortened the period of oxygen therapy.

Clinical Presentation and Outcome of Multisystem Inflammatory Syndrome in Children in Dhaka Shishu (Children) Hospital

Background: The increasing trend in multisystem inflammatory syndrome in children (MIS-C) during Covid-19 pandemic is alarming. Understanding the clinical course and outcome will give the clinical and public health implications of this syndrome.
 Objectives: This study was conducted to find out the clinical presentation, course of the disease and outcome of the children and adolescents of MIS-C.
 Methods: This observational study was conducted in the department of Pediatric Nephrology, Dhaka Shishu (Children) Hospital, Dhaka, Bangladesh, from August 2020 to October 2020. Total 12 children of MIS-C diagnosed according to WHO diagnostic criteria of MIS-C were included after taking written informed consent from the parents. Mean, median and standard deviation were calculated for the continuous variables.
 Results: The age ranged from 17 days to 13 years, 56% were male, 17% were positive for SARS-CoV-2 by RT-PCR and 4(33%) had history of the COVID-19 exposure. Organsystem involvement included bilateral pneumonia in 92%, myocarditis in 78%, swollen hands and feet in 67%, mucocutaneous involvement in 50%, diarrhea in 50%, musculoskeletal involvement in 50%, acute kidney injury (AKI) in 33% patients and acute pancreatitis in 25% patients. The median duration of hospitalization was 11 days and ICU stay was 5 days. Mean duration of fever was 8.66 days. Kawasaki’s diseaselike features were documented in 50% patients and 4 of them had elevated level of procalcitonin and troponin I. Markedly elevated C reactive protein (CRP), Ferritin and D dimer in all patients were present. All patients with cardiac involvement had left ventricular dysfunction and ejection fraction was as low as 38.5%. Coronary-artery dilatation was documented in 33%. About 67% received intensive care with oxygen support by low flow nasal cannula or face mask, 33% received vasoactive support and systemic glucocorticoid, 50% received intravenous immunoglobulin (IVIG) plus methyl prednisolone. Antiplatelet and anticoagulant therapy was given in 75% and 33% patients respectively. Out of 12 patients 2 died, the contributing cause of death included complications like hypotension, shock, myocarditis, coagulopathy and AKI.
 Conclusion: MIS-C led to serious and life-threatening complications especially when there are cardiac involvement, hypotension and acute kidney injury.
 DS (Child) H J 2020; 36(2): 87-94

Stabilisation of the preterm infant in the delivery room using nasal high flow: A 5-year retrospective analysis.

This study reviews clinical outcomes after initiating a routine policy of preterm respiratory stabilisation using nasal high flow (HF) in the delivery room (DR). This was a retrospective observational cohort study in a single-centre neonatal intensive care unit and included all neonates born before 32weeks of gestation between 1 April 2015 and 31 March 2020. Stabilisation measures and outcomes were recorded including oxygen requirements, admission temperature, surfactant administration, invasive ventilation within 72h of birth, bronchopulmonary dysplasia (BPD) and death. There were 491 eligible babies during the 5-year epoch. 292 were stabilised using HF in the DR. The median admission temperature in babies transferred on HF was 36.8°C, and the median FiO2 at admission was 25%. 45% of these infants received surfactant. At 72 postnatal hours, 78% were either sustained on HF or were either self-ventilating in air (SVIA) or receiving low-flow nasal cannula (LFNC) respiratory support. 27% were intubated within 7days. At 36weeks postmenstrual age, 36% of survivors had BPD. We have demonstrated that preterm babies <32weeks can be effectively stabilised on HF in the DR.

Safety of air medical transport of patients with COVID-19 by personnel using routine personal protective equipment.

ObjectiveAir medical transport of patients with known or suspected coronavirus disease 2019 (COVID‐19) likely represents a high‐risk exposure to crew members as aircraft cabins are quite small resulting in close personal contact. The actual risk to medical crew members is not known.MethodsWe conducted an institutional review board‐exempt, retrospective study of air medical transport of patients with known or suspected COVID‐19 by 8 programs in the Four Corners Region to determine the number of symptomatic COVID‐19 among air medical crew members compared to total exposure time. All programs used similar routine personal protective equipment (PPE), including N‐95 masks and eye protection. Total exposure time was considered from time of first patient contact until handoff at a receiving hospital.ResultsThere were 616 air transports: 62% by fixed‐wing and 38% by rotor‐wing aircraft between March 15 and September 6, 2020. Among transported patients, 407 (66%) were confirmed COVID+ and 209 (34%) were under investigation. Patient contact time ranged from 38 to 432 minutes with an average of 140 minutes. The total exposure time for medical crew was 2924 hours; exposure time to confirmed COVID+ patients was 2008 hours. Only 30% of patients were intubated, and the remainder had no oxygen (8%), low‐flow nasal cannula (42%), mask (11%), high‐flow nasal cannula (4.5%), and continuous positive airway pressure or bilevel positive airway pressure (3.5%). Two flight crew members out of 108 developed COVID that was presumed related to work.ConclusionsAir medical transport of patients with known or suspected COVID‐19 using routine PPE is considered effective for protecting medical crew members, even when patients are not intubated. This has implications for health care personnel in any setting that involves care of patients with COVID‐19 in similarly confined spaces.

Impact of Low Flow Nasal Cannula Failure Criteria on High Flow Nasal Cannula Utilization: A Quality Improvement Project

Impact of Low Flow Nasal Cannula Failure Criteria on High Flow Nasal Cannula Utilization: A Quality Improvement Project

Update on the Role of High-Flow Nasal Cannula in Infants with Bronchiolitis.

Bronchiolitis (BR), a lower respiratory tract infection mainly caused by respiratory syncytial virus (RSV), can be very severe. Presently, adequate nutritional support and oxygen therapy remain the only interventions recommended to treat patients with BR. For years, mild BR cases were treated with noninvasive standard oxygen therapy (SOT), i.e., with cold and poorly or totally non-humidified oxygen delivered by an ambient headbox or low-flow nasal cannula. Children with severe disease were intubated and treated with invasive mechanical ventilation (IMV). To improve SOT and overcome the disadvantages of IMV, new measures of noninvasive and more efficient oxygen administration have been studied. Bi-level positive air way pressure (BiPAP), continuous positive airway pressure (CPAP), and high-flow nasal cannula (HFNC) are among them. For its simplicity, good tolerability and safety, and the good results reported in clinical studies, HFNC has become increasingly popular and is now widely used. However, consistent guidelines for initiation and discontinuation of HFNC are lacking. In this narrative review, the role of HFNC to treat infants with BR is discussed. An analysis of the literature showed that, despite its widespread use, the role of HFNC in preventing respiratory failure in children with BR is not precisely defined. It is not established whether it can offer greater benefits compared to SOT and when and in which infants it can replace CPAP or BiPAP. The analysis of the results clearly indicates the need for multicenter studies and official guidelines. In the meantime, HFNC can be considered a safe and effective method to treat children with mild to moderate BR who do not respond to SOT.

Visual Diagnosis: Tension Pneumothorax with Evolving Cysts in an Infant.

1. Ariel Stein, MD*,† 2. Helena Molero, MD*,† 3. Donavon Hess, MD, PhD*,‡ 4. Mark Luquette, MD*,§ 5. Michael B. Pitt, MD*,† 1. *University of Minnesota School of Medicine, Minneapolis, MN 2. †Department of Pediatrics 3. ‡Department of Surgery, and 4. §Department of Laboratory Medicine, University of Minnesota Masonic Children’s Hospital, Minneapolis, MN * Abbreviations: CPAM: : congenital pulmonary airway malformation ED: : emergency department RSV: : respiratory syncytial virus A 5-month-old previously healthy term male infant presents to a rural emergency department (ED) for a 1-week history of increasing congestion, poor oral intake, and a temperature of 103°F (39.4°C). He is being treated with amoxicillin for presumed pneumonia. His examination in the ED is significant for scattered rhonchi and mild dehydration. His chest radiograph reveals inflammatory changes without a focal infiltrate (Fig 1). However, because this is his fourth presentation to the ED during this illness, he is admitted for observation. During the next 2 days his respiratory distress and tachypnea progressively worsen. On day 3 of his hospitalization he begins having episodes of desaturation and worsening retractions refractory to oxygen via low-flow nasal cannula. His examination at this time is significant for diffuse rhonchi throughout both lung fields with decreased air entry at the lung bases. Because his clinical status is deteriorating, he is transferred to a higher level of care. Figure 1. Anteroposterior and lateral chest radiographs on hospital day 1 show patchy, predominantly perihilar airspace opacities, consistent with viral inflammatory/reactive airway disease. No lobar consolidation. No pneumothorax. On arrival at the referral center he is lethargic, with decreased breath sounds and persistent desaturations. A respiratory swab polymerase chain reaction is positive for respiratory syncytial virus (RSV). His chest radiograph reveals a large right-sided tension pneumothorax (Fig 2). A pigtail chest tube is emergently placed, and his work of breathing improves. Within 2 days he is no longer requiring supplemental oxygen. The medical team is unable to successfully put the chest tube to water seal, however, because each time it is sealed there is a rapid re-accumulation of his pneumothorax. After several unsuccessful attempts, his chest tube is placed back to suction and he is airlifted, via helicopter, to a pediatric tertiary care center for further evaluation, now 11 …

Randomised controlled trial to assess the effectiveness of apnoeic oxygenation in adults using low-flow or high-flow nasal cannula with head side elevation versus usual care to prevent desaturation during endotracheal intubation in the emergency department (ApOxED): study protocol

IntroductionApnoeic oxygenation is a process of delivering continuous oxygen through nasal cannula during direct laryngoscopy. The oxygen that is delivered through these nasal cannulas is either low flow or high...

High-flow nasal cannula vs standard respiratory care in pediatric procedural sedation: A randomized controlled pilot trial.

Respiratory instability is frequently observed during pediatric procedural sedation. The aim of this trial was to estimate the impact of high-flow nasal cannula (HFNC) therapy on respiratory stability during sedation for upper gastrointestinal tract endoscopy in children. Prospective randomized controlled non-blinded single-center pilot trial. Children were randomly allocated to receive either HFNC (2 L/kg/min) or low-flow nasal oxygen cannula (LFNC, standard care). FiO2 was titrated to maintain SpO2 94% to 98% in both groups. Primary outcome was the number of events of respiratory instability defined by prespecified criteria (hypoxia, hypercapnia, apnea). Secondary outcomes included type and duration of events, number of interventions to regain respiratory stability and cumulative doses of medication. Fifty children (mean age, 12.3 ± 3.1 years) were enrolled and treated with HFNC (n = 25) or LFNC (n = 25). Patient and intervention characteristics were not different in the two study groups, including total oxygen flow rate. Mean (SD) number of respiratory events in the HFNC group was 2.0 ± 1.9 events compared to 2.0 ± 1.4 events in the LFNC group (P = .65; 95% CI of difference, -1.0 to 1.0). There was no difference for any secondary outcome criteria, percentage of patients for any outcome criteria and no difference in the number of respiratory events or airway management maneuvers per patient between treatment groups. HFNC did not increase respiratory stability in sedated children undergoing upper gastrointestinal tract endoscopy compared to LFNC.

Aerosol risk with noninvasive respiratory support in patients with COVID-19.

ObjectivesThis study evaluates aerosol production with high‐flow nasal cannula (HFNC) and noninvasive positive pressure ventilation (NIPPV) compared to 6 L/min by low‐flow nasal cannula.MethodsTwo healthy volunteers were randomized to control (6 L/min by low‐flow nasal cannula), NIPPV, or HFNC using block randomization. NIPPV conditions were studied using continuous positive airway pressures of 5, 10, and 15 cm H2O with an FiO2 of 1.0 delivered via full‐face mask. HFNC conditions included flow rates of 30 and 40 L/min with an FiO2 of 1.0 with and without coughing. HFNC and low‐flow nasal cannula conditions were repeated with and without participants wearing a surgical mask. Six aerosol sizes (0.3, 1.0, 2.5, 5, and 10 µm) and total aerosol mass were measured at 2 and 6 ft from the participant's nasopharynx.ResultsThere was no significant difference in aerosol production between either HFNC or NIPPV and control. There was also no significant difference with the use of a procedural mask over the HFNC. There was significant variation between the 2 participants, but in neither case was there a difference compared to control. There was an aerosol‐time trend, but there does not appear to be a difference between either flow rate, pressure, or control. Furthermore, there was no accumulation of total aerosol particles over the total duration of the experiment in both HFNC and NIPPV conditions.ConclusionsHFNC and NIPPV did not increase aerosol production compared to 6 L/min by low‐flow nasal cannula in this experiment involving healthy volunteers.

High-flow nasal cannula versus standard oxygen therapy assisting sedation during endoscopic retrograde cholangiopancreatography in high risk cases (OTHER): study protocol of a randomised multicentric trial

BackgroundEndoscopic retrograde cholangiopancreatography (ERCP) is an increasingly common intervention in the treatment of pancreaticobiliary disorders. Patients are often elderly with complex co-morbidities. While monitored anaesthesia care with sedation is commonly used for most cases, few would require general anaesthesia with an endotracheal tube. Both low-flow and high-flow nasal cannulas (HFNC) are established ways of delivering supplemental oxygen, but it is unclear whether one technique is better than the other. HFNC seems a promising tool for advanced procedures but evidence to support its application in high-risk ERCP cases is limited. The rate of oxygen desaturation during endoscopy has been reported to be as high as 11%–50% and the method of oxygen delivery for ERCP merits further study.Methods/designThis is a prospective, randomised, multicentre trial comparing the efficacy of oxygen supplementation through HFNC versus low-flow nasal cannula during ERCP, in a cohort of patients at risk of adverse respiratory events. A total of 132 patients will be recruited across three sites and randomly assigned to either the low-flow or the HFNC group. The primary outcome is the proportion of patients experiencing hypoxia, defined by any event of SpO2 < 90%. The secondary outcomes include parameters centred on oxygenation, requirement of airway manoeuvres, successful completion of procedure, perioperative complications, patient satisfaction and cost analysis of the consumables. An intention-to-treat principle will be applied while analysing.DiscussionThe demand for ERCPs is likely to increase in the future with the aging population. Our study results may lead to improved outcomes and reduce airway-related complications in patients undergoing ERCPs. The results will be presented at national and international meetings and published in peer-reviewed journals.Trial registrationwww.ANZCTR.org.au, CTRN12619000397112. Registered on 12 March 2019.

LMA\xae Gastro\u2122 Airway for endoscopic retrograde cholangiopancreatography: a retrospective observational analysis

BackgroundVarious airway techniques have been employed for endoscopic procedures, with an aim to optimise patient outcomes by improving airway control and preventing hypoxia whilst avoiding the need for intubation. The LMA® Gastro™ Airway, a novel dual channel supraglottic airway technique, has been described as such a device. Its utility alongside sedation with low flow nasal cannula and general anaesthesia (GA) with intubation for endoscopic retrograde cholangiopancreatography (ERCP) procedures was evaluated.MethodsDetails of all the ERCPs performed in our institution from March 2017 to June 2018 were carefully recorded in the patients’ electronic case records. Data on the successful completion of ERCP through LMA® Gastro™ Airway; any difficulty encountered by the gastroenterologists; and adverse events were recorded. Episodes of hypoxia (SpO2 < 92%) and haemodynamic parameters were compared across the three groups: LMA® Gastro™ vs. sedation with low flow nasal cannula vs. GA with an endotracheal tube (ETT).ResultsOne hundred seventy-seven ERCP procedures were performed during the study period. The LMA® Gastro™ Airway was employed in 64 procedures (36%) on 59 patients. Of these 64 procedures, ERCP was successfully completed with LMA® Gastro™ Airway in 63 (98%) instances, with only one case requiring conversion to an endotracheal tube. This instance followed difficulty in negotiating the endoscope through LMA® Gastro™ Airway. No episodes of hypoxia or hypercapnia were documented in both LMA® Gastro™ and GA with ETT groups. One sedation case with nasal cannula was noted to have hypoxia. Adverse intraoperative events were recognised in 2 cases of LMA® Gastro™: one had minimal blood stained secretions from the oral cavity that resolved with suctioning; the other developed mild laryngospasm which resolved spontaneously within a few minutes.ConclusionIn patients undergoing ERCP, the LMA® Gastro™ airway demonstrated a high success rate for ERCP completion. Ventilation was well maintained with minimal intraoperative and postoperative adverse events. This technique may have a role in higher risk groups such as high ASA (American Society of Anesthesiologists) status, or those with potential airway difficulties such as high body mass index and those with known or suspected sleep apnoea.

Apnoeic oxygenation and ventilation: go with the flow

Apnoeic oxygenation and ventilation: go with the flow

Late onset oxygen requirement following neonatal therapeutic hypothermia.

To investigate the characteristics of infants with neonatal encephalopathy (NE) receiving therapeutic hypothermia (TH) who developed late onset oxygen requirement during or after rewarming. Infants were stratified by receiving (a) new onset isolated oxygen requirements during or after rewarming; (b) no respiratory support during hospital stay; and (c) invasive and/or non-invasive respiratory support before or during cooling. Of 136 infants treated with TH, 49 (36%) did not require any respiratory support, and 78 (57.4%) received invasive or non-invasive support before or during cooling. Nine infants (6.6%) developed late onset oxygen requirement. The late onset oxygen requirement started at median age of 3.8days (IQR 3.6-5.2) and ended at median 7.5days (IQR 5.8-12.7). Total hours of O2 exposure were median 62.0 (IQR 24.4-112.6). Maximum support was low-flow nasal cannula from 100% oxygen source with a flow rate of 40-250mL/min. Infants in this group had higher Apgar scores, milder metabolic acidosis and no seizures. Three infants had diagnostic investigations without significant findings. A small percentage of neonates with NE developed late onset oxygen requirement during or after rewarming. Late oxygen requirement was associated with evidence of less severe perinatal hypoxia-ischaemia.

Improvement of arterial oxygenation using the double trunk mask above low flow nasal cannula: a pilot study

Improvement of arterial oxygenation using the double trunk mask above low flow nasal cannula: a pilot study

Low-Flow Nasal Cannula Hydrogen Therapy.

BackgroundMolecular hydrogen (H2) is a biologically active gas that is widely used in the healthcare sector. In recent years, on-site H2 gas generators, which produce high-purity H2 by water electrolysis, have begun to be introduced in hospitals, clinics, beauty salons, and fitness clubs because of their ease of use. In general, these generators produce H2 at a low-flow rate, so physicians are concerned that an effective blood concentration of H2 may not be ensured when the gas is delivered through a nasal cannula. Therefore, this study aimed to evaluate blood concentrations of H2 delivered from an H2 gas generator via a nasal cannula.MethodsWe administered 100% H2, produced by an H2 gas generator, at a low-flow rate of 250 mL/min via a nasal cannula to three spontaneously breathing micro miniature pigs. An oxygen mask was placed over the nasal cannula to administer oxygen while minimizing H2 leakage, and a catheter was inserted into the carotid artery to monitor the arterial blood H2 concentration.ResultsDuring the first hour of H2 inhalation, the mean (standard error (SE)) H2 concentrations and saturations in the arterial blood of the three pigs were 1,560 (413) nL/mL and 8.85% (2.34%); 1,190 (102) nL/mL and 6.74% (0.58%); and 1,740 (181) nL/mL and 9.88% (1.03%), respectively. These values are comparable to the concentration one would expect if 100% of the H2 released from the H2 gas generator is taken up by the body.ConclusionsInhalation of 100% H2 produced by an H2 gas generator, even at low-flow rates, can increase blood H2 concentrations to levels that previous non-clinical and clinical studies demonstrated to be therapeutically effective. The combination of a nasal cannula and an oxygen mask is a convenient way to reduce H2 leakage while maintaining oxygenation.

Bubble continuous positive airway pressure for children with high-risk conditions and severe pneumonia in Malawi: an open label, randomised, controlled trial

SummaryBackgroundPneumonia is the leading cause of death among children globally. Most pneumonia deaths in low-income and middle-income countries (LMICs) occur among children with HIV infection or exposure, severe malnutrition, or hypoxaemia despite antibiotics and oxygen. Non-invasive bubble continuous positive airway pressure (bCPAP) is considered a safe ventilation modality that might improve child pneumonia survival. bCPAP outcomes for high-risk African children with severe pneumonia are unknown. Since most child pneumonia hospitalisations in Africa occur in non-tertiary district hospitals without daily physician oversight, we aimed to examine whether bCPAP improves severe pneumonia mortality in such settings.MethodsThis open-label, randomised, controlled trial was done in the general paediatric ward of Salima District Hospital, Malawi. We enrolled children aged 1–59 months old with WHO-defined severe pneumonia and either HIV infection or exposure, severe malnutrition, or an oxygen saturation of less than 90%. Children were randomly assigned 1:1 to low-flow nasal cannula oxygen or nasal bCPAP. Non-physicians administered care; the primary outcome was hospital survival. Primary analyses were by intention-to-treat and interim and adverse events analyses per protocol. This trial is registered with ClinicalTrials.gov, number NCT02484183, and is closed.FindingsWe screened 1712 children for eligibility between June 23, 2015, and March 21, 2018. The data safety and monitoring board stopped the trial for futility after 644 of the intended 900 participants were enrolled. 323 children were randomly assigned to oxygen and 321 to bCPAP. 35 (11%) of 323 children who received oxygen died in hospital, as did 53 (17%) of 321 who received bCPAP (relative risk 1·52; 95% CI 1·02–2·27; p=0·036). 13 oxygen and 17 bCPAP patients lacked hospital outcomes and were considered lost to follow-up. Suspected adverse events related to treatment occurred in 11 (3%) of 321 children receiving bCPAP and 1 (<1%) of 323 children receiving oxygen. Four bCPAP and one oxygen group deaths were classified as probable aspiration episodes, one bCPAP death as probable pneumothorax, and six non-death bCPAP events included skin breakdown around the nares.InterpretationbCPAP treatment in a paediatric ward without daily physician supervision did not reduce hospital mortality among high-risk Malawian children with severe pneumonia, compared with oxygen. The use of bCPAP within certain patient populations and non-intensive care settings might carry risk that was not previously recognised. bCPAP in LMICs needs further evaluation before wider implementation for child pneumonia care.FundingBill & Melinda Gates Foundation, International AIDS Society, Health Empowering Humanity.

Effect of nebulizer type, delivery interface, and flow rate on aerosol drug delivery to spontaneously breathing pediatric and infant lung models.

Different types of nebulizers, interfaces, and flow rates are used to deliver aerosolized medications to children. The purpose of this study was to determine the effect of nebulizer type, delivery interface, and flow rate on aerosol drug delivery to spontaneously breathing pediatric and infant lung models. A teaching mannequin was attached to a sinusoidal pump via a collecting filter at the bronchi to simulate a spontaneously breathing child (Vt: 250 mL, RR: 20 bpm and Ti: 1 second) and infant (Vt = 100 mL, RR = 30 bpm, Ti: 0.7 seconds). Albuterol sulfate was nebulized with jet (Misty Max 10; Cardinal Health) and mesh (Aerogen Solo; Aerogen) nebulizers using a low-flow nasal cannula (LFNC; Hudson), a high-flow nasal cannula (HFNC; Fisher & Paykel), face mask (FM; Hudson), and mouthpiece (MP; Cardinal Health). While all interfaces were used in the pediatric study, only LFNC, HFNC, and FM were tested in the infant study. The mesh nebulizer was tested at 2, 4, and 6 L/min with LFNC, 4 and 6 L/min with HFNC, and 6 L/min with FM and MP. The jet nebulizer was operated at 6 and 8 L/min with FM and 6 L/min with LFNC, HFNC, and MP (n = 5). The drug was eluted from the filter and analyzed by spectrophotometry. Factorial analysis of variance and post hoc comparisons were used for data analysis. P < .05 was considered statistically significant. Delivery efficiency of mesh nebulizers is two to fourfold more than jet nebulizers used with HFNC, FM, and MP. No statistical difference was found between jet and mesh nebulizers used with LFNC in infants (P = .643) and pediatrics (P = .255). Aerosol delivery with MP was the best compared to other interfaces used in pediatrics (P < .05). As the second-best interface in aerosol drug delivery, the delivery efficiency of FM was greater than HFNC (P = .0001) and LFNC (P = .0001). Increasing flow rate with LFNC and HFNC decreased aerosol delivery with the mesh nebulizer in both infants and pediatrics. The type of nebulizer, delivery interface, and flow rate used in the treatment of children affect aerosol drug delivery.

Hypopharyngeal oxygen concentration and pressures delivered by low flow nasal cannula in preterm infants: Relationship with flow, gas mixture, and infant's weight.

Low flow nasal cannula (LFNC) are frequently used in preterm infants. However, the delivered inspired oxygen concentration and airway pressures are not well established. To determine the fraction of inspired oxygen (FiO2 ) and hypopharyngeal pressures generated by LFNC at different gas flows, gas mixture concentrations and infant's weight. Serial samples of hypopharyngeal gas were obtained in 33 very low birth weight infants who were receiving oxygen with LFNC. Measurements were obtained with different gas flows and oxygen concentrations. FiO2 was measured using an electrochemical cell analyzer and hypopharyngeal pressures with a pressure transducer. 33 infants with a mean BW of 910 ± 284 g and 27 ± 1.7 weeks gestational age were studied at 36 ± 22 days after birth. FiO2 increased proportionally to gas flow, but with large variability: median (range) FiO 2 were 0.33 (0.23-0.54), 0.44 (0.29-0.67), 0.57 (0.33-0.81), and 0.69 (0.51-0.92) at 0.1, 0.3, 0.5, and 1 L/minute, respectively. Significantly higher mean FiO 2 were observed despite low flows in infants ≤ 1000 g compared to those > 1000 g (0.5 ± 0.1 vs 0.4 ± 0.07 at 0.3 L/minute; 0.66 ± 0.09 vs 0.5 ± 0.08 with 0.5 L/minute, respectively, P < .05). Hypopharyngeal pressures increased proportionally to gas flow with high variability: mean ± standard deviation pressures were 1.5 ± 0.8; 2.8 ± 1.2; 4.6 ± 1.3; 6.1 ± 1.6 cm H 2 O at 0.5, 1, 2, and 3 L/minute of gas flow. Peak pressures > 15 cm H 2 O were frequently observed with gas flows ≥ 2 L/min. Large variability in FiO2 and hypopharyngeal pressures were observed with oxygen administration through LFNC. Very high FiO 2 were observed despite low flows in infants < 1000 g. Excessive peak pressures can be generated with flows ≥ 2 L/minute especially among infants < 1000 g.

A pilot study of heated and humidified low flow oxygen therapy: An assessment in infants with mild and moderate bronchiolitis (HHOT AIR study).

Heated and humidified high flow nasal cannula oxygen therapy has been used in children with severe bronchiolitis. No data exists in children with mild to moderate bronchiolitis requiring lower flows of heated and humidified oxygen therapy. We conducted a prospective, randomized pilot study of standard dry oxygen (control) versus heated and humidified low flow nasal cannula (HHLFNC), <4 liters per minute (LPM) oxygen, (treatment) in healthy children ≤24 months old with bronchiolitis. Clinical assessments were made using Respiratory Distress Assessment Instrument (RDAI), respiratory rate (RR), and oxygen saturation. Thirty-two children were enrolled (16 participants in each group). There was no significant difference in mean RDAI over time between groups. There was a significant difference in mean RDAI over time within control group, at hour 12, and treatment group, at hour 1, compared to baseline. RDAI in the treatment group was overall lower over time compared to control group. There was no significant difference in mean RR over time between or within groups, between mean length of stay and duration of oxygen requirement. Subgroup analyses showed lower RDAI in subjects that had RSV infection, male gender, and non-black race. The use of HHLFNC oxygen therapy may provide more comfort and may result in more rapid improvements in RDAI compared to standard dry oxygen therapy over time. HHFLNC is safe and well tolerated compared to standard dry oxygen. Larger studies are needed to assess the clinical efficacy of HHLFNC oxygen therapy.