Anaesthesia
-
Observational Study
Changes in qualitative and quantitative ultrasound assessment of the gastric antrum before and after elective caesarean section in term pregnant women: a prospective cohort study.
Ultrasound measurement of the antral cross-sectional area allows a quantitative estimate of gastric contents in non-pregnant adults, but this relationship may be affected by compression of the stomach exerted by the gravid uterus during pregnancy. This study aimed to assess differences in quantitative (Perlas score) and qualitative (antral cross-sectional area) ultrasound assessments of the gastric antrum performed immediately before and after caesarean section. Forty-three women having elective caesarean section performed under spinal anaesthesia were studied in the semirecumbent and semirecumbent-right lateral positions. ⋯ The distance between the skin and the antrum, and the aorta and the antrum, decreased significantly in both positions after surgery. We suggest that our results indicate that stomach contents remain largely unchanged in women having elective caesarean section, but antral cross-sectional area decreases, especially in the semirecumbent position, related to a change in the position of the stomach within the abdomen. This implies that the relationship of antral cross-sectional area to volume of stomach contents, which has been determined for non-pregnant subjects, may not apply in term pregnant women.
-
Poor sleep is an increasingly recognised problem with chronic pain and further increases the effect on daily function. To identify the relationship between chronic pain, opioid analgesia and sleep quality, this study investigated activity and sleep patterns in patients taking opioid and non-opioid analgesia for chronic back pain. Thirty-one participants (10 healthy controls, 21 patients with chronic pain: 6 on non-opioid medication; 15 on opioid medication) were assessed using actigraphy, polysomnography and questionnaires. ⋯ Patients on high doses of opioids (> 100 mg morphine-equivalent/day) demonstrated distinctly abnormal brain activity during sleep suggesting that polysomnography is necessary to detect sleep disturbance in this population in the absence of irregular rest-activity behaviour. Night-time sleep disturbance is common in individuals suffering from chronic pain and may be further exacerbated by opioid treatment. Considerations must be made regarding the appropriate use of combined actigraphy and miniaturised polysomnography for future population-based studies.