RESUMO
OBJECTIVE@#To evaluate the safety of preoxygenation with high-flow nasal oxygenation in elderly patients during induction of general anesthesia with endotracheal intubation.@*METHODS@#Fifty-six elderly patients without difficult airway were randomized equally into high-flow nasal oxygen group (HF group) and conventional mask oxygen group (M group). Preoxygenation was performed for 5 min before induction of general anesthesia and endotracheal intubation. Oxygenation was maintained during laryngoscopy in HF group, and ventilation lasted until laryngoscopy in M group. For all the patients, the general data, cross-sectional area (CSA) of the gastric antrum measured by ultrasonography, arterial partial pressure of oxygen (PaO2), arterial partial pressure of carbon dioxide (PaCO2) and arterial oxygen saturation (cSO2) were recorded before preoxygenation (T1), at 5 min of preoxygenation (T2) and immediately after intubation (T3). The safety time of asphyxia, intubation time, times of mask ventilation and postoperative complications were compared between the two groups.@*RESULTS@#The general data were comparable between the two groups. After 5 min of preoxygenation, PaO2 and cSO2 were significantly increased in both groups, and PaO2 was significantly higher in HF group than in M group (F=118.108 vs 9.511, P < 0.05). Both PaO2 and cSO2 decreased after intubation, but PaO2 decreased more slowly in HF group and still remained higher than that at T1; cSO2 decreased significantly in M group to a lower level than that at T1. Compared with those in M group, the patients in HF group showed a significantly longer safety time of asphyxia (t=5.305, P < 0.05) with fewer times of mask ventilation (χ2= 6.720, P < 0.05). PaCO2 increased after intubation in both groups but was comparable between the two groups (F=3.138, P > 0.05).@*CONCLUSION@#High-flow nasal oxygen is safe, simple and effective for pre-oxygenation, which, as compared with the conventional oxygen mask, improves arterial oxygen partial pressure and prolongs the safety time of asphyxia to ensure the safety of airway management during induction of general anesthesia in elderly patients with endotracheal intubation.
Assuntos
Idoso , Humanos , Anestesia Geral , Asfixia , Intubação Intratraqueal , Oxigênio , Pressão ParcialRESUMO
High-flow nasal oxygenation (HFNO) is a promising new technique for anesthesiologists. The use of HFNO during the induction of anesthesia and during upper airway surgeries has been initiated, and its applications have been rapidly growing ever since. The advantages of this technique include its easy set-up, high tolerability, and its abilities to produce positive airway pressure and a high fraction of inspired oxygen and to influence the clearance of carbon dioxide to some extent. HFNO, via a nasal cannula, can provide oxygen both to patients who can breathe spontaneously and to those who are apneic; further, this technique does not interfere with bag-mask ventilation, attempts at laryngoscopy for tracheal intubation, and surgical procedures conducted in the airway. In this review, we describe the techniques associated with HFNO and the advantages and disadvantages of HFNO based on the current state of knowledge.