Postoperative Hypoxaemia After Major Abdominal Vascular Surgery

Abstract

We have studied the severity and duration of nocturnal hypoxaemia before operation and for the first five nights after operation after elective major abdominal vascular surgery. Oxygen supplementation was almost 100% effective in keeping oxygen saturation greater than 90% during the early postoperative period; however, 50% of patients spent prolonged periods with an SpO2 less than 85% during at least one night after operation. The risk of severe hypoxaemia persists well beyond the current prescription of supplementary oxygen in these high risk patients. A significant association exists between the mean preoperative overnight saturation value and the nocturnal saturation observed subsequently in the later postoperative period.

Czy znieczulenie zewnątrzoponowe zmniejsza częstość incydentów desaturacji w okresie pooperacyjnym u chorych operowanych z powodu tętniaka aorty brzusznej?

“…In the postoperative period during the observation of ICU patients, myocardial infarction was diagnosed in three patients (5%): one from group A and two from group B. Although some authors have reported that epidural anaesthesia reduced the risk of myocardial hypoxia [8,16], the majority have not confirmed such effects [4,6,12,17], which is consistent with our findings.…”

“…Based on a study in PACU patients, Moller [18] evaluated the incidence of desaturation events and their severity and noted that postoperative hypoxia is a common phenomenon and that oxygen therapy does not protect against hypoxaemia events, which was consistent with the conclusions that were reported by Rosenberg [13] and Russell [12]. Similarly, episodes of hypoxaemia in our study group were common and comprised 90% of patients in both groups.…”

“…After 70 hours, no incidents of hypoxaemia were observed in any patient. The above results confirm the observations of Rosenberg [10,11], Pedersen [13] and Reeder [12], which indicate that postoperative hypoxaemia does not have to include the immediate postoperative period and can develop later, even up to 7 days after surgery, according to some authors [9,10,13,16]. Lower incidences of hypoxaemia in the immediate postoperative period are likely to result from favourable effects of mechanical ventilation, lung expansion and the use of concentrations of a respiratory mixture of oxygen higher than 21%.…”

A comparison of epidural tramadol and epidural morphine for postoperative analgesia

“…2~ The respiratory depressant effects of opioid analgesia also have an important role in the production of postoperative hypoxaemia. 17 Previous clinical reports have also shown that parenteral morphine results in greater, and clinically important, respiratory depression than equi-analgesic doses of parenteral tramadol. 8.9 The absence of respiratory depression following epidural or parenteral tramadol compared with epidural or parenteral morphine may be attributed to the different mechanisms of their analgesic actions.…”

O sistema respiratório e o idoso: implicações anestésicas

“…Apesar da administração de oxigênio, talvez a metade de todos os pacientes admitidos em unidades de recuperação pós-anestésica tenha diminuição na saturação de oxigênio através da oximetria, em valores de 90% ou mais. A diminuição na concentração arterial de oxigênio pode acontecer particularmente entre o segundo e o quinto dia pós-operatório 64 , pois neste período a suplementação de oxigênio geralmente é descontinuada, sendo porém necessária ainda a administração de opióides para controlar a dor 65 . O uso de analgesia controlada pelo paciente tanto venosa quanto peridural atua de maneira mais consistente, reduz a sonolência, pois diminui a sobredose, porém pode produzir depressão respiratória em idosos mais frágeis 66 .…”