Pathophysiology of Apnea, Hypoxia, and Preoxygenation

Abstract

Because intubation becomes a long procedure as potential, arterial oxygen (O 2) desaturation should be taken into account during the intubation. Since oxygen reserves are not always sufficient to meet the duration of intubation, preoxygenation should be routine before anesthetic induction and tracheal intubation. Surveys show that maximal preoxygenation increases oxygen reserves in the body and significantly delays arterial hemoglobin desaturation and hypoxia. In cases of respiratory insufficiency oxygenation can be improved by positive end expiratory pressure (PEEP) or pressure support. Effective technique and FeO 2 monitoring can increase the effectiveness of preoxygenation and thus increase the safety margin. Preoxygenation failures have to be identified and alternative oxygenation methods must be readily available in order to be applied quickly and easily. Although genetic and environmental factors play a role in diseases such as heart attack, stroke and cancer, which have become the cause of the worst death in the twenty-first century, the underlying problem in the development of these pathological conditions is hypoxia. Better understanding of hypoxic areas in ischemic tissues or growing tumors as well as increased knowledge of hypoxia cellular and molecular responses will allow possible applications in the treatment of major diseases associated with tissue hypoxia.

L’intubation chez l’adulte à l’urgence : une séquence à respecter (partie 1)

“…Une canule nasale peut également être ajoutée sous le masque à réservoir pour complémenter l'administration d'O2 (12). Idéalement, la période de préoxygénation devrait durer trois minutes (12,21,22). Si le temps ne le permet pas, huit grandes respirations profondes maximales en 60 secondes peuvent également prodiguer une préoxygénation adéquate (2,12,21).…”

“…L'oxygénation apnéique s'effectue en administrant de l'O2 à 15L/min via une lunette nasale (LN) qui sera maintenue en place durant l'étape de l'intubation (étape 6). L'oxygénation apnéique prolonge théoriquement le délai avant la survenue d'une désaturation en réapprovisionnant continuellement l'O2 consommé(12,19,21,22). Toutefois, l'oxygénation apnéique ne pourra pas compenser pour une préoxygénation inefficace.…”

A Structured Approach to the Collapsed Athlete: The First Minute Matters

“…First, an American Heart Association consensus statement expressed that the appropriate timeframe for intervening with oxygen delivery is unclear and "in non asphyxial arrest, compression without ventilation may be adequate" (11). Young healthy athletes have a large functional residual capacity, and even with apnea, it takes a few minutes for desaturation of hemoglobin to occur (12). Second, to minimize cognitive burden, the steps are strategically organized to address common causes for collapse and prioritizing the most time-sensitive etiologies specific to this population.…”

Paramedics’ Success and Complications in Prehospital Pediatric Intubation: A Meta-Analysis

“…13 Pediatric tolerance to apnea is less efficient than adult, due to high oxygen demand and low oxygen reserves. 14 While many Emergency Medical Services consider pediatric intubation as an essential paramedic skill, there is notable divergence in the utilization of this skill across the United States. 15 The specialized training in procedural and decisionmaking competencies establish and elevate quality standards in the paramedics outside of a hospital setting.…”