Clinical Research
- Washout of Dead Space
- Work of Breathing
- Gas Conditioning
- Metabolic Work
- Distending Pressure
- Comparisons To Alternative Therapies
- Heliox Usage
Effect of low flow and high flow oxygen delivery on exercise tolerance and sensation of dyspnea. A study comparing the transtracheal catheter and nasal prongs by Dewan NA & Bell CW (Chest. 1994 105:1).
Dewan and Bell describe the effectiveness of high flow nasal cannula in maintaining oxygenation and work tolerance. This paper shows that high flow oxygen delivery by nasal cannula is more effective at maintaining blood oxygen saturation and work performance than low flow oxygen cannula. Furthermore, the data indicate that high flow nasal cannula therapy is similar in efficacy to transtracheal catheters, which are intended to attenuate the effects of anatomical dead space on breathing efficiency. This paper therefore supports the proposed mechanism of action for high flow nasal cannula related to dead space washout.
Impact on Oxygenation and Ventilation in an Acute Lung Injury Model by Frizzola, M, Miller, TL, Rodriguez, ME, Zhu, Y, Rojas, J, Hesek, A, Stump, A, Shaffer, TH, & Dysart, K. Pediatr Pulmonol. 2010.
Frizzola and colleagues demonstrate that by way of purging anatomical dead space in a piglet model, High Flow Therapy (HFT) results in a ventilation effect that is not matched by CPAP therapy. The study shows that the impact HFT has on blood gas parameters is a function of flow, and not inadvertent pressure development. Moreover, these data demonstrate that cannulae which do not obstruct the nares, as compared to more obstructive cannulae, produce the optimal effect on blood O2 and CO2 at significantly lower flow rates and subsequently lower resulting end-distending pressure development. In simpler terms, the more of the nares that are exposed the greater the degree of flush. Therefore, this validation research for the mechanisms behind the efficacy of HFT provides evidence that HFT should be applied with minimally occlusive nasal prongs, and flow parameters set to optimize anatomical flush, and not administered in a way to promote pressure development.
Numa, AH., & Newth, CJL. Anatomic dead space in infants and children. J. Appl. Physiol. 80(5): 1485-89, 1996.
Numa and Newth demonstrate that extrathoracic dead space volumes in infants are typically 2.5 to 3 fold greater, expressed as volume per unit of body weight, compared to adults. A review of literature shows that adult extrathoracic dead space volume (i.e., anatomic reservoir) is on average 0.8 ml/kg of body weight. In the neonatal / pediatric population, extrathoracic dead space volumes show a significant, inverse relationship with age. Herein, neonates have an extrathoracic dead space volume of around 3 ml/kg, which decreases with age to below 1.5 ml/kg after 2 years of age. Only by six years of age did some of the children studies have an extrathoracic dead space volume similar in relative size to adults.
Research in high flow therapy: Mechanisms of action by Dysart, K, Miller, TL, Wolfson, MR, & Shaffer, TH (Respiratory Medicine. 2009).
Dysart et al summarizes the mechanisms of action behind the efficacy of HFT via nasal cannula. The mechanisms discussed include washout of nasopharyngeal dead space, reduction of inspiratory resistance in the nasopharynx, improvement in airway and lung mechanics, mild distending pressure and a reduction in energy expenditure associated with inspiratory gas conditioning.
Effect of low flow and high flow oxygen delivery on exercise tolerance and sensation of dyspnea. A study comparing the transtracheal catheter and nasal prongs by Dewan NA & Bell CW (Chest. 1994 105:1).
Dewan and Bell describe the effectiveness of high flow nasal cannula in maintaining oxygenation and work tolerance. This paper shows that high flow oxygen delivery by nasal cannula is more effective at maintaining blood oxygen saturation and work performance than low flow oxygen cannula. Furthermore, the data indicate that high flow nasal cannula therapy is similar in efficacy to transtracheal catheters, which are intended to attenuate the effects of anatomical dead space on breathing efficiency. This paper therefore supports the proposed mechanism of action for high flow nasal cannula related to dead space washout.
Impact on Oxygenation and Ventilation in an Acute Lung Injury Model by Frizzola, M, Miller, TL, Rodriguez, ME, Zhu, Y, Rojas, J, Hesek, A, Stump, A, Shaffer, TH, & Dysart, K. Pediatr Pulmonol. 2010.
Frizzola and colleagues demonstrate that by way of purging anatomical dead space in a piglet model, High Flow Therapy (HFT) results in a ventilation effect that is not matched by CPAP therapy. The study shows that the impact HFT has on blood gas parameters is a function of flow, and not inadvertent pressure development. Moreover, these data demonstrate that cannulae which do not obstruct the nares, as compared to more obstructive cannulae, produce the optimal effect on blood O2 and CO2 at significantly lower flow rates and subsequently lower resulting end-distending pressure development. In simpler terms, the more of the nares that are exposed the greater the degree of flush. Therefore, this validation research for the mechanisms behind the efficacy of HFT provides evidence that HFT should be applied with minimally occlusive nasal prongs, and flow parameters set to optimize anatomical flush, and not administered in a way to promote pressure development.
Research in high flow therapy: Mechanisms of action by Dysart, K, Miller, TL, Wolfson, MR, & Shaffer, TH (Respiratory Medicine. 2009).
Dysart et al summarizes the mechanisms of action behind the efficacy of HFT via nasal cannula. The mechanisms discussed include washout of nasopharyngeal dead space, reduction of inspiratory resistance in the nasopharynx, improvement in airway and lung mechanics, mild distending pressure and a reduction in energy expenditure associated with inspiratory gas conditioning.
Effect of low flow and high flow oxygen delivery on exercise tolerance and sensation of dyspnea. A study comparing the transtracheal catheter and nasal prongs by Dewan NA & Bell CW (Chest. 1994 105:1).
Dewan and Bell describe the effectiveness of high flow nasal cannula in maintaining oxygenation and work tolerance. This paper shows that high flow oxygen delivery by nasal cannula is more effective at maintaining blood oxygen saturation and work performance than low flow oxygen cannula. Furthermore, the data indicate that high flow nasal cannula therapy is similar in efficacy to transtracheal catheters, which are intended to attenuate the effects of anatomical dead space on breathing efficiency. This paper therefore supports the proposed mechanism of action for high flow nasal cannula related to dead space washout.
Impact on Oxygenation and Ventilation in an Acute Lung Injury Model by Frizzola, M, Miller, TL, Rodriguez, ME, Zhu, Y, Rojas, J, Hesek, A, Stump, A, Shaffer, TH, & Dysart, K. Pediatr Pulmonol. 2010.
Frizzola and colleagues demonstrate that by way of purging anatomical dead space in a piglet model, High Flow Therapy (HFT) results in a ventilation effect that is not matched by CPAP therapy. The study shows that the impact HFT has on blood gas parameters is a function of flow, and not inadvertent pressure development. Moreover, these data demonstrate that cannulae which do not obstruct the nares, as compared to more obstructive cannulae, produce the optimal effect on blood O2 and CO2 at significantly lower flow rates and subsequently lower resulting end-distending pressure development. In simpler terms, the more of the nares that are exposed the greater the degree of flush. Therefore, this validation research for the mechanisms behind the efficacy of HFT provides evidence that HFT should be applied with minimally occlusive nasal prongs, and flow parameters set to optimize anatomical flush, and not administered in a way to promote pressure development.
Numa, AH., & Newth, CJL. Anatomic dead space in infants and children. J. Appl. Physiol. 80(5): 1485-89, 1996.
Numa and Newth demonstrate that extrathoracic dead space volumes in infants are typically 2.5 to 3 fold greater, expressed as volume per unit of body weight, compared to adults. A review of literature shows that adult extrathoracic dead space volume (i.e., anatomic reservoir) is on average 0.8 ml/kg of body weight. In the neonatal / pediatric population, extrathoracic dead space volumes show a significant, inverse relationship with age. Herein, neonates have an extrathoracic dead space volume of around 3 ml/kg, which decreases with age to below 1.5 ml/kg after 2 years of age. Only by six years of age did some of the children studies have an extrathoracic dead space volume similar in relative size to adults.
Research in high flow therapy: Mechanisms of action by Dysart, K, Miller, TL, Wolfson, MR, & Shaffer, TH (Respiratory Medicine. 2009).
Dysart et al summarizes the mechanisms of action behind the efficacy of HFT via nasal cannula. The mechanisms discussed include washout of nasopharyngeal dead space, reduction of inspiratory resistance in the nasopharynx, improvement in airway and lung mechanics, mild distending pressure and a reduction in energy expenditure associated with inspiratory gas conditioning.
Numa, AH., & Newth, CJL. Anatomic dead space in infants and children. J. Appl. Physiol. 80(5): 1485-89, 1996.
Numa and Newth demonstrate that extrathoracic dead space volumes in infants are typically 2.5 to 3 fold greater, expressed as volume per unit of body weight, compared to adults. A review of literature shows that adult extrathoracic dead space volume (i.e., anatomic reservoir) is on average 0.8 ml/kg of body weight. In the neonatal / pediatric population, extrathoracic dead space volumes show a significant, inverse relationship with age. Herein, neonates have an extrathoracic dead space volume of around 3 ml/kg, which decreases with age to below 1.5 ml/kg after 2 years of age. Only by six years of age did some of the children studies have an extrathoracic dead space volume similar in relative size to adults.
Research in high flow therapy: Mechanisms of action by Dysart, K, Miller, TL, Wolfson, MR, & Shaffer, TH (Respiratory Medicine. 2009).
Dysart et al summarizes the mechanisms of action behind the efficacy of HFT via nasal cannula. The mechanisms discussed include washout of nasopharyngeal dead space, reduction of inspiratory resistance in the nasopharynx, improvement in airway and lung mechanics, mild distending pressure and a reduction in energy expenditure associated with inspiratory gas conditioning.
Effect of low flow and high flow oxygen delivery on exercise tolerance and sensation of dyspnea. A study comparing the transtracheal catheter and nasal prongs by Dewan NA & Bell CW (Chest. 1994 105:1).
Dewan and Bell describe the effectiveness of high flow nasal cannula in maintaining oxygenation and work tolerance. This paper shows that high flow oxygen delivery by nasal cannula is more effective at maintaining blood oxygen saturation and work performance than low flow oxygen cannula. Furthermore, the data indicate that high flow nasal cannula therapy is similar in efficacy to transtracheal catheters, which are intended to attenuate the effects of anatomical dead space on breathing efficiency. This paper therefore supports the proposed mechanism of action for high flow nasal cannula related to dead space washout.
Impact on Oxygenation and Ventilation in an Acute Lung Injury Model by Frizzola, M, Miller, TL, Rodriguez, ME, Zhu, Y, Rojas, J, Hesek, A, Stump, A, Shaffer, TH, & Dysart, K. Pediatr Pulmonol. 2010.
Frizzola and colleagues demonstrate that by way of purging anatomical dead space in a piglet model, High Flow Therapy (HFT) results in a ventilation effect that is not matched by CPAP therapy. The study shows that the impact HFT has on blood gas parameters is a function of flow, and not inadvertent pressure development. Moreover, these data demonstrate that cannulae which do not obstruct the nares, as compared to more obstructive cannulae, produce the optimal effect on blood O2 and CO2 at significantly lower flow rates and subsequently lower resulting end-distending pressure development. In simpler terms, the more of the nares that are exposed the greater the degree of flush. Therefore, this validation research for the mechanisms behind the efficacy of HFT provides evidence that HFT should be applied with minimally occlusive nasal prongs, and flow parameters set to optimize anatomical flush, and not administered in a way to promote pressure development.
Effect of low flow and high flow oxygen delivery on exercise tolerance and sensation of dyspnea. A study comparing the transtracheal catheter and nasal prongs by Dewan NA & Bell CW (Chest. 1994 105:1).
Dewan and Bell describe the effectiveness of high flow nasal cannula in maintaining oxygenation and work tolerance. This paper shows that high flow oxygen delivery by nasal cannula is more effective at maintaining blood oxygen saturation and work performance than low flow oxygen cannula. Furthermore, the data indicate that high flow nasal cannula therapy is similar in efficacy to transtracheal catheters, which are intended to attenuate the effects of anatomical dead space on breathing efficiency. This paper therefore supports the proposed mechanism of action for high flow nasal cannula related to dead space washout.
Impact on Oxygenation and Ventilation in an Acute Lung Injury Model by Frizzola, M, Miller, TL, Rodriguez, ME, Zhu, Y, Rojas, J, Hesek, A, Stump, A, Shaffer, TH, & Dysart, K. Pediatr Pulmonol. 2010.
Frizzola and colleagues demonstrate that by way of purging anatomical dead space in a piglet model, High Flow Therapy (HFT) results in a ventilation effect that is not matched by CPAP therapy. The study shows that the impact HFT has on blood gas parameters is a function of flow, and not inadvertent pressure development. Moreover, these data demonstrate that cannulae which do not obstruct the nares, as compared to more obstructive cannulae, produce the optimal effect on blood O2 and CO2 at significantly lower flow rates and subsequently lower resulting end-distending pressure development. In simpler terms, the more of the nares that are exposed the greater the degree of flush. Therefore, this validation research for the mechanisms behind the efficacy of HFT provides evidence that HFT should be applied with minimally occlusive nasal prongs, and flow parameters set to optimize anatomical flush, and not administered in a way to promote pressure development.
Research in high flow therapy: Mechanisms of action by Dysart, K, Miller, TL, Wolfson, MR, & Shaffer, TH (Respiratory Medicine. 2009).
Dysart et al summarizes the mechanisms of action behind the efficacy of HFT via nasal cannula. The mechanisms discussed include washout of nasopharyngeal dead space, reduction of inspiratory resistance in the nasopharynx, improvement in airway and lung mechanics, mild distending pressure and a reduction in energy expenditure associated with inspiratory gas conditioning.
Effect of low flow and high flow oxygen delivery on exercise tolerance and sensation of dyspnea. A study comparing the transtracheal catheter and nasal prongs by Dewan NA & Bell CW (Chest. 1994 105:1).
Dewan and Bell describe the effectiveness of high flow nasal cannula in maintaining oxygenation and work tolerance. This paper shows that high flow oxygen delivery by nasal cannula is more effective at maintaining blood oxygen saturation and work performance than low flow oxygen cannula. Furthermore, the data indicate that high flow nasal cannula therapy is similar in efficacy to transtracheal catheters, which are intended to attenuate the effects of anatomical dead space on breathing efficiency. This paper therefore supports the proposed mechanism of action for high flow nasal cannula related to dead space washout.
Numa, AH., & Newth, CJL. Anatomic dead space in infants and children. J. Appl. Physiol. 80(5): 1485-89, 1996.
Numa and Newth demonstrate that extrathoracic dead space volumes in infants are typically 2.5 to 3 fold greater, expressed as volume per unit of body weight, compared to adults. A review of literature shows that adult extrathoracic dead space volume (i.e., anatomic reservoir) is on average 0.8 ml/kg of body weight. In the neonatal / pediatric population, extrathoracic dead space volumes show a significant, inverse relationship with age. Herein, neonates have an extrathoracic dead space volume of around 3 ml/kg, which decreases with age to below 1.5 ml/kg after 2 years of age. Only by six years of age did some of the children studies have an extrathoracic dead space volume similar in relative size to adults.
Impact on Oxygenation and Ventilation in an Acute Lung Injury Model by Frizzola, M, Miller, TL, Rodriguez, ME, Zhu, Y, Rojas, J, Hesek, A, Stump, A, Shaffer, TH, & Dysart, K. Pediatr Pulmonol. 2010.
Frizzola and colleagues demonstrate that by way of purging anatomical dead space in a piglet model, High Flow Therapy (HFT) results in a ventilation effect that is not matched by CPAP therapy. The study shows that the impact HFT has on blood gas parameters is a function of flow, and not inadvertent pressure development. Moreover, these data demonstrate that cannulae which do not obstruct the nares, as compared to more obstructive cannulae, produce the optimal effect on blood O2 and CO2 at significantly lower flow rates and subsequently lower resulting end-distending pressure development. In simpler terms, the more of the nares that are exposed the greater the degree of flush. Therefore, this validation research for the mechanisms behind the efficacy of HFT provides evidence that HFT should be applied with minimally occlusive nasal prongs, and flow parameters set to optimize anatomical flush, and not administered in a way to promote pressure development.
Effect of low flow and high flow oxygen delivery on exercise tolerance and sensation of dyspnea. A study comparing the transtracheal catheter and nasal prongs by Dewan NA & Bell CW (Chest. 1994 105:1).
Dewan and Bell describe the effectiveness of high flow nasal cannula in maintaining oxygenation and work tolerance. This paper shows that high flow oxygen delivery by nasal cannula is more effective at maintaining blood oxygen saturation and work performance than low flow oxygen cannula. Furthermore, the data indicate that high flow nasal cannula therapy is similar in efficacy to transtracheal catheters, which are intended to attenuate the effects of anatomical dead space on breathing efficiency. This paper therefore supports the proposed mechanism of action for high flow nasal cannula related to dead space washout.
Research in high flow therapy: Mechanisms of action by Dysart, K, Miller, TL, Wolfson, MR, & Shaffer, TH (Respiratory Medicine. 2009).
Dysart et al summarizes the mechanisms of action behind the efficacy of HFT via nasal cannula. The mechanisms discussed include washout of nasopharyngeal dead space, reduction of inspiratory resistance in the nasopharynx, improvement in airway and lung mechanics, mild distending pressure and a reduction in energy expenditure associated with inspiratory gas conditioning.
Effect of low flow and high flow oxygen delivery on exercise tolerance and sensation of dyspnea. A study comparing the transtracheal catheter and nasal prongs by Dewan NA & Bell CW (Chest. 1994 105:1).
Dewan and Bell describe the effectiveness of high flow nasal cannula in maintaining oxygenation and work tolerance. This paper shows that high flow oxygen delivery by nasal cannula is more effective at maintaining blood oxygen saturation and work performance than low flow oxygen cannula. Furthermore, the data indicate that high flow nasal cannula therapy is similar in efficacy to transtracheal catheters, which are intended to attenuate the effects of anatomical dead space on breathing efficiency. This paper therefore supports the proposed mechanism of action for high flow nasal cannula related to dead space washout.
Research in high flow therapy: Mechanisms of action by Dysart, K, Miller, TL, Wolfson, MR, & Shaffer, TH (Respiratory Medicine. 2009).
Dysart et al summarizes the mechanisms of action behind the efficacy of HFT via nasal cannula. The mechanisms discussed include washout of nasopharyngeal dead space, reduction of inspiratory resistance in the nasopharynx, improvement in airway and lung mechanics, mild distending pressure and a reduction in energy expenditure associated with inspiratory gas conditioning.
Effect of low flow and high flow oxygen delivery on exercise tolerance and sensation of dyspnea. A study comparing the transtracheal catheter and nasal prongs by Dewan NA & Bell CW (Chest. 1994 105:1).
Dewan and Bell describe the effectiveness of high flow nasal cannula in maintaining oxygenation and work tolerance. This paper shows that high flow oxygen delivery by nasal cannula is more effective at maintaining blood oxygen saturation and work performance than low flow oxygen cannula. Furthermore, the data indicate that high flow nasal cannula therapy is similar in efficacy to transtracheal catheters, which are intended to attenuate the effects of anatomical dead space on breathing efficiency. This paper therefore supports the proposed mechanism of action for high flow nasal cannula related to dead space washout.
Research in high flow therapy: Mechanisms of action by Dysart, K, Miller, TL, Wolfson, MR, & Shaffer, TH (Respiratory Medicine. 2009).
Dysart et al summarizes the mechanisms of action behind the efficacy of HFT via nasal cannula. The mechanisms discussed include washout of nasopharyngeal dead space, reduction of inspiratory resistance in the nasopharynx, improvement in airway and lung mechanics, mild distending pressure and a reduction in energy expenditure associated with inspiratory gas conditioning.
Effect of low flow and high flow oxygen delivery on exercise tolerance and sensation of dyspnea. A study comparing the transtracheal catheter and nasal prongs by Dewan NA & Bell CW (Chest. 1994 105:1).
Dewan and Bell describe the effectiveness of high flow nasal cannula in maintaining oxygenation and work tolerance. This paper shows that high flow oxygen delivery by nasal cannula is more effective at maintaining blood oxygen saturation and work performance than low flow oxygen cannula. Furthermore, the data indicate that high flow nasal cannula therapy is similar in efficacy to transtracheal catheters, which are intended to attenuate the effects of anatomical dead space on breathing efficiency. This paper therefore supports the proposed mechanism of action for high flow nasal cannula related to dead space washout.
Research in high flow therapy: Mechanisms of action by Dysart, K, Miller, TL, Wolfson, MR, & Shaffer, TH (Respiratory Medicine. 2009).
Dysart et al summarizes the mechanisms of action behind the efficacy of HFT via nasal cannula. The mechanisms discussed include washout of nasopharyngeal dead space, reduction of inspiratory resistance in the nasopharynx, improvement in airway and lung mechanics, mild distending pressure and a reduction in energy expenditure associated with inspiratory gas conditioning.
Effect of low flow and high flow oxygen delivery on exercise tolerance and sensation of dyspnea. A study comparing the transtracheal catheter and nasal prongs by Dewan NA & Bell CW (Chest. 1994 105:1).
Dewan and Bell describe the effectiveness of high flow nasal cannula in maintaining oxygenation and work tolerance. This paper shows that high flow oxygen delivery by nasal cannula is more effective at maintaining blood oxygen saturation and work performance than low flow oxygen cannula. Furthermore, the data indicate that high flow nasal cannula therapy is similar in efficacy to transtracheal catheters, which are intended to attenuate the effects of anatomical dead space on breathing efficiency. This paper therefore supports the proposed mechanism of action for high flow nasal cannula related to dead space washout.
Impact on Oxygenation and Ventilation in an Acute Lung Injury Model by Frizzola, M, Miller, TL, Rodriguez, ME, Zhu, Y, Rojas, J, Hesek, A, Stump, A, Shaffer, TH, & Dysart, K. Pediatr Pulmonol. 2010.
Frizzola and colleagues demonstrate that by way of purging anatomical dead space in a piglet model, High Flow Therapy (HFT) results in a ventilation effect that is not matched by CPAP therapy. The study shows that the impact HFT has on blood gas parameters is a function of flow, and not inadvertent pressure development. Moreover, these data demonstrate that cannulae which do not obstruct the nares, as compared to more obstructive cannulae, produce the optimal effect on blood O2 and CO2 at significantly lower flow rates and subsequently lower resulting end-distending pressure development. In simpler terms, the more of the nares that are exposed the greater the degree of flush. Therefore, this validation research for the mechanisms behind the efficacy of HFT provides evidence that HFT should be applied with minimally occlusive nasal prongs, and flow parameters set to optimize anatomical flush, and not administered in a way to promote pressure development.
Research in high flow therapy: Mechanisms of action by Dysart, K, Miller, TL, Wolfson, MR, & Shaffer, TH (Respiratory Medicine. 2009).
Dysart et al summarizes the mechanisms of action behind the efficacy of HFT via nasal cannula. The mechanisms discussed include washout of nasopharyngeal dead space, reduction of inspiratory resistance in the nasopharynx, improvement in airway and lung mechanics, mild distending pressure and a reduction in energy expenditure associated with inspiratory gas conditioning.