scholarly journals Risk of airway fire with the use of KTP laser and high flow humidified oxygen delivery in a laryngeal surgery model

2022 ◽  
Vol 12 (1) ◽  
Author(s):  
Lucy Huang ◽  
Adam Badenoch ◽  
Marthinus Vermeulen ◽  
Shahid Ullah ◽  
Charmaine Woods ◽  
...  
Keyword(s):  
Oxygen Concentration ◽  
Ex Vivo ◽  
High Flow ◽  
Tissue Type ◽  
Ktp Laser ◽  
Ex Vivo Model ◽  
Laryngeal Surgery ◽  
High Flow Oxygen ◽  
Smoke Evacuation ◽  
Estimated Risk

AbstractAirway surgery presents a unique environment for operating room fire to occur. This study aims to explore the factors of combustion when using KTP laser with high flow oxygen in an ex-vivo model. The variables tested were varying tissue type, tissue condition, oxygen concentration, laser setting, and smoke evacuation in a stainless-steel model. Outcome measures were time of lasing to the first spark and/or flame. A multivariate Cox proportional hazard model was used to determine the risk of spark and flame across the different risk factors. For every 10% increase in oxygen concentration above 60% the risk of flame increased by a factor of 2.3. Continuous laser setting at 2.6 W increased the risk by a factor of 72.8. The risk of lasing adipose tissue is 7.3 times higher than that of muscle. Charred tissue increases the risk of flame by a factor of 92.8. Flame occurred without a preceding spark 93.6% of the time. Using KTP laser in the pulsed mode with low wattages, minimising lasing time, reducing the oxygen concentration and avoiding lasing adipose or charred tissue produce a relatively low estimated risk of spark or flame.

scholarly journals Risk of Airway Fire with the use of KTP Laser and High Flow Humidified Oxygen Delivery in a Laryngeal Surgery Model

2021 ◽  
Author(s):  
Lucy Huang ◽  
Adam Badenoch ◽  
Marthinus Vermeulen ◽  
Shahid Ullah ◽  
Charmaine Woods ◽  
...  
Keyword(s):  
Oxygen Concentration ◽  
Ex Vivo ◽  
High Flow ◽  
Tissue Type ◽  
Ktp Laser ◽  
Ex Vivo Model ◽  
Laryngeal Surgery ◽  
High Flow Oxygen ◽  
Smoke Evacuation ◽  
Estimated Risk

Abstract Background Airway surgery presents a unique environment for operating room fire to occur. This study aims to explore the factors of combustion when using KTP laser with high flow oxygen in an ex-vivo model. MethodsThe variables tested were varying tissue type, tissue condition, oxygen concentration, laser setting, and smoke evacuation in a stainless-steel model. Outcome measures were time of lasing to the first spark and/or flame. A multivariate Cox proportional hazard model was used to determine the risk of spark and flame across the different risk factors. ResultsFor every 10% increase in oxygen concentration above 60% the risk of flame increased by a factor of 2.3. Continuous laser setting at 2.6W increased the risk by a factor of 72.8. The risk of lasing adipose tissue is 7.3 times higher than that of muscle. Charred tissue increases the risk of flame by a factor of 92.8. Flame occurred without a preceding spark 93.6% of the time. Conclusions Using KTP laser in the pulsed mode with low wattages, minimising lasing time, reducing the oxygen concentration and avoiding lasing adipose or charred tissue produce a relatively low estimated risk of spark or flame.

scholarly journals Anesthesia-related Safety Profile of a High-energy Ultrasonic Scalpel in Oropharyngeal and Laryngeal Surgery: An Ex Vivo Model

Cureus ◽  
2019 ◽  
Author(s):  
Nikolay R Sapundzhiev ◽  
Georgi Davidov ◽  
Viliyan Platikanov ◽  
George S Stoyanov ◽  
Valentin Ignatov
Keyword(s):  
Safety Profile ◽  
Ex Vivo ◽  
High Energy ◽  
Ex Vivo Model ◽  
Ultrasonic Scalpel ◽  
Laryngeal Surgery

scholarly journals Oxygenation laryngoscope vs. nasal standard and nasal high flow oxygenation in a technical simulation of apnoeic oxygenation

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
H. Herff ◽  
W. A. Wetsch ◽  
S. Finke ◽  
F. Dusse ◽  
T. Mitterlechner ◽  
...  
Keyword(s):  
Airway Management ◽  
Oxygen Concentration ◽  
High Flow ◽  
Nasal Cannula ◽  
Pure Oxygen ◽  
High Flow Oxygen ◽  
Failed Airway ◽  
Oxygen Group ◽  
And Control ◽  
Apnoeic Oxygenation

Abstract Background Failed airway management is the major contributor for anaesthesia-related morbidity and mortality. Cannot-intubate-cannot-ventilate scenarios are the most critical emergency in airway management, and belong to the worst imaginable scenarios in an anaesthetist’s life. In such situations, apnoeic oxygenation might be useful to avoid hypoxaemia. Anaesthesia guidelines recommend careful preoxygenation and application of high flow oxygen in difficult intubation scenarios to prevent episodes of deoxygenation. In this study, we evaluated the decrease in oxygen concentration in a model when using different strategies of oxygenation: using a special oxygenation laryngoscope, nasal oxygen, nasal high flow oxygen, and control. Methods In this experimental study we compared no oxygen application as a control, standard pure oxygen application of 10 l·min− 1 via nasal cannula, high flow 90% oxygen application at 20 l·min− 1 using a special nasal high flow device, and pure oxygen application via our oxygenation laryngoscope at 10 l·min− 1. We preoxygenated a simulation lung to 97% oxygen concentration and connected this to the trachea of a manikin model simulating apnoeic oxygenation. Decrease in oxygen concentration in the simulation lung was measured continuously for 20 min. Results Oxygen concentration in the simulation lung dropped from 97 ± 1% at baseline to 40 ± 1% in the no oxygen group, to 80 ± 1% in the standard nasal oxygen group, and to 73 ± 2% in the high flow nasal oxygenation group. However, it remained at 96 ± 0% in the oxygenation laryngoscope group (p < 0.001 between all groups). Conclusions In this technical simulation, oxygenation via oxygenation laryngoscope was more effective than standard oxygen insufflation via nasal cannula, which was more effective than nasal high flow insufflation of 90% oxygen.

Effect of ex vivo extracorporeal membrane oxygenation flow dynamics on immune response

Perfusion ◽  
2019 ◽  
Vol 34 (1_suppl) ◽  
pp. 5-14 ◽  
Author(s):  
Katrina K Ki ◽  
Margaret R Passmore ◽  
Chris Hoi Houng Chan ◽  
Maximillian V Malfertheiner ◽  
Mahe Bouquet ◽  
...  
Keyword(s):  
Inflammatory Response ◽  
Extracorporeal Membrane Oxygenation ◽  
Ex Vivo ◽  
Antigen Expression ◽  
High Flow ◽  
Flow Dynamics ◽  
Low Flow ◽  
Technological Advancement ◽  
Ex Vivo Model ◽  
Membrane Oxygenation

Background: Extracorporeal membrane oxygenation is a life-saving support for heart and/or lung failure patients. Despite technological advancement, abnormal physiology persists and has been associated with subsequent adverse events. These include thrombosis, bleeding, systemic inflammatory response syndrome and infection. However, the underlying mechanisms are yet to be elucidated. We aimed to investigate whether the different flow dynamics of extracorporeal membrane oxygenation would alter immune responses, specifically the overall inflammatory response, leukocyte numbers and activation/adhesion surface antigen expression. Methods: An ex vivo model was used with human whole blood circulating at 37°C for 6 hours at high (4 L/minute) or low (1.5 L/minute) flow dynamics, with serial blood samples taken for analysis. Results: During high flow, production of interleukin-1β (p < 0.0001), interleukin-6 (p = 0.0075), tumour necrosis factor-α (p = 0.0013), myeloperoxidase (p < 0.0001) and neutrophil elastase (p < 0.0001) were significantly elevated over time compared to low flow, in particular at 6 hours. While the remaining assessments exhibited minute changes between flow dynamics, a consistent trend of modulation in leukocyte subset numbers and phenotype was observed at 6 hours. Conclusion: We conclude that prolonged circulation at high flow triggers a prominent pro-inflammatory cytokine response and activates neutrophil granule release, but further research is needed to better characterize the effect of flow during extracorporeal membrane oxygenation.

High Flow Oxygen Therapy and the Pressure to Feed Infants With Acute Respiratory Illness

2020 ◽  
Vol 5 (4) ◽  
pp. 1006-1010
Author(s):  
Jennifer Raminick ◽  
Hema Desai
Keyword(s):  
Clinical Practice ◽  
Clinical Practice Guidelines ◽  
Practice Guidelines ◽  
Oxygen Therapy ◽  
Respiratory Illness ◽  
High Flow ◽  
Oral Feeding ◽  
Respiratory Support ◽  
Acute Respiratory Illness ◽  
High Flow Oxygen

Purpose Infants hospitalized for an acute respiratory illness often require the use of noninvasive respiratory support during the initial stage to improve their breathing. High flow oxygen therapy (HFOT) is becoming a more popular means of noninvasive respiratory support, often used to treat respiratory syncytial virus/bronchiolitis. These infants present with tachypnea and coughing, resulting in difficulties in coordinating sucking and swallowing. However, they are often allowed to feed orally despite having high respiratory rate, increased work of breathing and on HFOT, placing them at risk for aspiration. Feeding therapists who work with these infants have raised concerns that HFOT creates an additional risk factor for swallowing dysfunction, especially with infants who have compromised airways or other comorbidities. There is emerging literature concluding changes in pharyngeal pressures with HFOT, as well as aspiration in preterm neonates who are on nasal continuous positive airway pressure. However, there is no existing research exploring the effect of HFOT on swallowing in infants with acute respiratory illness. This discussion will present findings from literature on HFOT, oral feeding in the acutely ill infant population, and present clinical practice guidelines for safe feeding during critical care admission for acute respiratory illness. Conclusion Guidelines for safety of oral feeds for infants with acute respiratory illness on HFOT do not exist. However, providers and parents continue to want to provide oral feeds despite clinical signs of respiratory distress and coughing. To address this challenge, we initiated a process change to use clinical bedside evaluation and a “cross-systems approach” to provide recommendations for safer oral feeds while on HFOT as the infant is recovering from illness. Use of standardized feeding evaluation and protocol have improved consistency of practice within our department. However, further research is still necessary to develop clinical practice guidelines for safe oral feeding for infants on HFOT.

1849: Systematic Evaluation of 21μm Thulium Laser Device for Treatment of Benign Prostatic Enlargement in an Ex-VIVO Model

2007 ◽  
Vol 177 (4S) ◽  
pp. 614-614 ◽  
Author(s):  
Gunnar Wendt-Nordahl ◽  
Stefanie Huckele ◽  
Patrick Honeck ◽  
Peter Aiken ◽  
Thomas Knoll ◽  
...  
Keyword(s):  
Ex Vivo ◽  
Systematic Evaluation ◽  
Thulium Laser ◽  
Laser Device ◽  
Benign Prostatic Enlargement ◽  
Ex Vivo Model ◽  
Prostatic Enlargement

Porcine small intestine, a good ex vivo model to investigate absorption and metabolism of natural products

2017 ◽  
Author(s):  
J Houriet ◽  
YE Arnold ◽  
C Petit ◽  
YN Kalia ◽  
JL Wolfender
Keyword(s):  
Natural Products ◽  
Small Intestine ◽  
Ex Vivo ◽  
Ex Vivo Model

Effects of Two Different Doses of Hirudin on APTT, Determined with Eight Different Reagents

1995 ◽  
Vol 73 (02) ◽  
pp. 219-222 ◽  
Author(s):  
Manuel Monreal ◽  
Luis Monreal ◽  
Rafael Ruiz de Gopegui ◽  
Yvonne Espada ◽  
Ana Maria Angles ◽  
...  
Keyword(s):  
Ex Vivo ◽  
Anticoagulant Activity ◽  
Subcutaneous Administration ◽  
In Vitro Study ◽  
Ex Vivo Model ◽  
Suitable Candidate ◽  
Significant Prolongation ◽  
High Doses ◽  
Different Doses

SummaryThe APTT has been considered the most suitable candidate to monitor the anticoagulant activity of hirudin. However, its use is hampered by problems of standardization, which make the results heavily dependent on the responsiveness of the reagent used. Our aim was to investigate if this different responsiveness of different reagents when added in vitro is to be confirmed in an ex vivo study.Two different doses of r-hirudin (CGP 39393), 0.3 mg/kg and 1 mg/kg, were administered subcutaneously to 20 New Zealand male rabbits, and the differences in prolongation of APTT 2 and 12 h later were compared, using 8 widely used commercial reagents. All groups exhibited a significant prolongation of APTT 2 h after sc administration of hirudin, both at low and high doses. But this prolongation persisted 12 h later only when the PTTa reagent (Boehringer Mannheim) was used. In general, hirudin prolonged the APTT most with the silica- based reagents.In a further study, we compared the same APTT reagents in an in vitro study in which normal pooled plasma was mixed with increasing amount of hirudin. We failed to confirm a higher sensitivity for silica- containing reagents. Thus, we conclude that subcutaneous administration of hirudin prolongs the APTT most with the silica-based reagents, but this effect is exclusive for the ex vivo model.

The Effect of Pentosan Polysulphate (SP54) on the Fibrinolytic Enzyme System - A Human Volunteer and Experimental Animal Study

1985 ◽  
Vol 54 (04) ◽  
pp. 833-837 ◽  
Author(s):  
N A Marsh ◽  
P M Peyser ◽  
L J Creighton ◽  
M Mahmoud ◽  
P J Gaffney
Keyword(s):  
Plasminogen Activator ◽  
Surface Effect ◽  
Ex Vivo ◽  
Vena Cava ◽  
Tissue Type ◽  
Similar Response ◽  
Small Contribution ◽  
Thrombosis Model ◽  
Pentosan Polysulphate

SummaryPentosan polysulphate causes an increase in plasminogen activator activity in plasma both after oral ingestion and after subcutaneous injection. The effect is greatest after 3 h and has disappeared by 6 h. Repeat doses by mouth over 5 days elicit a similar response. The recorded increase in activity is due largely to the release of tissue-type plasminogen activator (tPA) from the endothelium according to the antigen assay although there could be a small contribution from Factor XH-related “intrinsic” fibrinolysis induced in vitro. SP54 enhances activity ex vivo by a non-specific surface effect, and this phenomenon may contribute the increased levels of activity seen in vitro. Administration of SP54 to animals elicits a similar increase in activator activity, the intramuscular route being slightly more effective. Results with an inferior vena cava thrombosis model in the rat suggest that pentosan polysulphate may induce a thrombolytic effect.

Sign in / Sign up

Export Citation Format

Share Document