))
Physiology of High-Flow Nasal Cannula (HFNC)
Manage episode 383453043 series 3453614
コンテンツは Dr. Pradip Kamat, Dr. Rahul Damania, Dr. Pradip Kamat, and Dr. Rahul Damania によって提供されます。エピソード、グラフィック、ポッドキャストの説明を含むすべてのポッドキャスト コンテンツは、Dr. Pradip Kamat, Dr. Rahul Damania, Dr. Pradip Kamat, and Dr. Rahul Damania またはそのポッドキャスト プラットフォーム パートナーによって直接アップロードされ、提供されます。誰かがあなたの著作物をあなたの許可なく使用していると思われる場合は、ここで概説されているプロセスに従うことができますhttps://ja.player.fm/legal。
Today’s case presentation involves a 2-year-old girl who was previously healthy and was admitted to the Pediatric Intensive Care Unit (PICU) for acute respiratory distress characterized by increased work of breathing and wheezing.
Case Presentation
A 2-year-old girl with acute respiratory distress due to RSV infection
- Presented with increased work of breathing, wheezing, and no fever
- Started on High Flow Nasal Cannula (HFNC) therapy in the PICU
Key Elements:
- Prodrome of URI symptoms
- Increased respiratory effort (nasal flaring, intercostal retractions, decreased lung base air entry)
- HFNC improved the work of breathing and oxygen saturation
Physiology of HFNC
Mechanisms of Action
Washout of Nasopharyngeal Dead Space:
- HFNC clears nasopharyngeal dead space, improving oxygen efficiency.
- Reduces re-breathing of CO2 from the anatomical dead space.
- Enhances ventilation efficiency and oxygenation.
Reduction in Upper Airway Resistance:
- HFNC reduces resistance in the upper airway.
- Delivers rapid gas flow matching or exceeding natural inhalation rate.
- Eases breathing, especially in neonates and infants with narrow airways.
Optimal Conditioning of Gas:
- HFNC delivers heated and humidified oxygen, matching the body's conditions.
- Reduces energy expenditure and risk of airway irritation
- More comfortable and effective compared to cold, dry air delivery
Debunking the PEEP Theory (Positive End-Expiratory Pressure)
- HFNC generates minimal and variable PEEP.
- Amount of PEEP depends on factors like flow rate and cannula size
- Not as high or consistent as other respiratory support devices
Research Findings
- A 2022 CHEST study by Khemani et al. on children with bronchiolitis challenged the conventional understanding of HFNC's mechanisms.
- HFNC primarily reduces breathing effort but does not consistently increase lung volume (EELV) or tidal volume (VT).
- Reduction in the pressure rate product (PRP) indicates decreased breathing effort, but not significant alterations in EELV or VT.
Physiological Effects
- HR, RR, and SpO2 are key indicators of HFNC efficacy.
- HR and RR should approach normal ranges for the child's age.
- Improvement in SpO2 levels while maintaining or reducing FiO2 indicates a positive response.
Conclusion
- HFNC is a valuable tool in pediatric care for alleviating respiratory distress.
- Not a one-size-fits-all solution; vigilant monitoring and reassessment are crucial
- Recognizing HFNC's mechanisms allows for optimized bedside application.
Closing Remarks:
- Subscribe, share feedback, and leave a review on the podcast.
- Visit picudoconcall.org for more episodes and management cards.
- Hosted by Dr. Pradip Kamat and Dr. Rahul Damania
References
88 つのエピソード
シェア
