Supplementation of pre‐oxygenation in morbidly obese patients using nasopharyngeal oxygen insufflation

Abstract

SummaryDuring apnoea following induction of anaesthesia, morbidly obese patients may suffer a rapid decrease in oxygen saturation. This study compares pre-oxygenation alone with pre-oxygenation followed by nasopharyngeal oxygen insufflation on the onset of desaturation occurring during the subsequent apnoea. A randomised controlled trial was performed in 34 morbidly obese patients undergoing gastric bypass or gastric band surgery. Seventeen patients received nasopharyngeal oxygen supplementation following pre-oxygenation (Study group, body mass index = 41.8 (6.9) kg.m ). Time from the onset of apnoea until S p O 2 fell to 95% was compared between the two groups with a cut-off of 4 min. In the control group, the S p O 2 fell from 100% to 95% during the subsequent apnoea in 145 (27) s, with a significantly negative correlation (r 2 = 0.66, p < 0.05) between the time to desaturation to 95% and the body mass index. In the study group, the S p O 2 was maintained in 16 of 17 patients at 100% for 4 min when apnoea was terminated. In conclusion, nasopharyngeal oxygen insufflation following pre-oxygenation in morbidly obese patients delays the onset of oxyhaemoglobin desaturation during the subsequent apnoea.

Optimizing preoxygenation in adults

“…27 This technique has successfully been employed in obese patients, with DAWD increasing from a mean of 2.4 min without such a device to 4 min in 16 of 17 patients when oxygen was provided by a nasopharyngeal cannula at a rate of 5 L Á min -1 . 28 One of the drawbacks of this technique is that it requires an extra manipulation after induction of anesthesia. …”

Time to abandon awake fibreoptic intubation?

“…The administration of oxygen via nasal cannulae during conventional laryngoscopy or videolaryngoscopy extends the duration of safe apnoea [24][25][26], and is effective even in obese patients. For example, Ramachandran et al [27] simulated difficult airways in obese patients and found that supplemental oxygen administration was associated with a significant increase in the duration and frequency of oxygen saturations >95% after induction of anaesthesia and neuromuscular blockade.…”

La prise en charge des voies aériennes et l’oxygénation du patient obèse

“…[28][29][30][31] Baraka et al compared preoxygenation followed by nasopharyngeal oxygen insufflation (study group) with preoxygenation alone (control group) in morbidly obese patients placed in a 25°head-up position. 35 In the study group, 16 of 17 patients maintained oxygen saturation at 100% during four minutes of apnea. All 17 patients in the control group experienced oxygen desaturation from 100 to 95% in a mean time of 145 (27) sec.…”

“…ont comparé une technique de préoxygénation suivie par l'insufflation nasopharyngée d'oxygène (groupe à l'étude) à une technique de préoxygénation seule (groupe témoin) chez des patients obèses morbides positionnés avec la tête élevée à un angle de 25°. 35 Dans le groupe à l'étude, 16 des 17 patients ont maintenu leur saturation en oxygène à 100 % pendant quatre minutes d'apnée. Les 17 patients du groupe témoin ont subi une désaturation en oxygène de 100 à 95 % en un temps moyen de 145 (27) sec.…”