Dataset Information

Minimizing atelectasis formation during general anaesthesia-oxygen washout is a non-essential supplement to PEEP.

ABSTRACT:

Background

Following preoxygenation and induction of anaesthesia, most patients develop atelectasis. We hypothesized that an immediate restoration to a low oxygen level in the alveoli would prevent atelectasis formation and improve oxygenation during the ensuing anaesthesia.

Methods

We randomly assigned 24 patients to either a control group (n?=?12) or an intervention group (n?=?12) receiving an oxygen washout procedure directly after intubation. Both groups were, depending on body mass index, ventilated with a positive end-expiratory pressure (PEEP) of 6-8 cmH₂O during surgery. The atelectasis area was studied by computed tomography before emergence. Oxygenation levels were evaluated by measuring blood gases and calculating estimated venous admixture (EVA).

Results

The atelectasis areas expressed as percentages of the total lung area were 2.0 (1.5-2.7) (median [interquartile range]) and 1.8 (1.4-3.3) in the intervention and control groups, respectively. The difference was non-significant, and also oxygenation was similar between the two groups. Compared to oxygenation before the start of anaesthesia, oxygenation at the end of surgery was improved in the intervention group, mean (SD) EVA from 7.6% (6.6%) to 3.9% (2.9%) (P?=?.019) and preserved in the control group, mean (SD) EVA from 5.0% (5.3%) to 5.6% (7.1%) (P?=?.59).

Conclusion

Although the oxygen washout restored a low pulmonary oxygen level within minutes, it did not further reduce atelectasis size. Both study groups had small atelectasis and good oxygenation. These results suggest that a moderate PEEP alone is sufficient to minimize atelectasis and maintain oxygenation in healthy patients.

SUBMITTER: Ostberg E

PROVIDER: S-EPMC5441378 | biostudies-literature | 2017 Jun

REPOSITORIES: biostudies-literature

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Publications

Minimizing atelectasis formation during general anaesthesia-oxygen washout is a non-essential supplement to PEEP.

Östberg Erland E Auner Udo U Enlund Mats M Zetterström Henrik H Edmark Lennart L

Upsala journal of medical sciences 20170424 2

<h4>Background</h4>Following preoxygenation and induction of anaesthesia, most patients develop atelectasis. We hypothesized that an immediate restoration to a low oxygen level in the alveoli would prevent atelectasis formation and improve oxygenation during the ensuing anaesthesia.<h4>Methods</h4>We randomly assigned 24 patients to either a control group (n = 12) or an intervention group (n = 12) receiving an oxygen washout procedure directly after intubation. Both groups were, depending on bod ...[more]

PMID: 28434271

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Project description:Objectives: Thyroid nodules are common in adults, but only some of them are malignant. Ultrasound-guided fine-needle aspiration (FNA) is widely applied as a reliable and minimally invasive technique for evaluating thyroid nodules. However, the scarcity of FNA biopsy specimens poses a challenge to molecular diagnosis. This study aimed to evaluate the feasibility of FNA washout precipitation specimens as an effective supplement to the thyroid genetic test. Methods: A total of 115 patients with thyroid nodules were enrolled in our study. The BRAF V600E mutation status was detected in all FNA washout precipitation specimens and biopsy formalin-fixed paraffin-embedded (FFPE) specimens using an amplification refractory mutation system PCR (ARMS-PCR). All patients underwent cytological diagnoses; 79 patients also underwent surgery for histopathological analysis. Results: All the 115 samples were successfully analyzed using both FNA washout precipitation and biopsy FFPE specimens. The results showed that the BRAF V600E status detected in 96 FNA washout precipitation specimens were consistent with that in FNA biopsy FFPE specimens, including 41 BRAF V600E positive and 55 BRAF V600E negative, achieving a concordance rate of 84.4% (kappa = 0.689). Furthermore, the BRAF V600E mutation status using FNA washout precipitation specimens provided a 100.0% positive predictive value for diagnosing papillary thyroid carcinoma in patients with The Bethesda system for reporting thyroid cytopathology (TBSRTC) V. Besides, the BRAF V600E mutation status was positive in 90.9% (10/11) FNA washout precipitation specimens from patients with capsule invasion, achieving a higher overall sensitivity of 100.0%, compared with 57.1% of FNA washout precipitation specimens from patients without capsule invasion. Conclusion: These results suggested that FNA washout precipitation specimens might be a valuable supplementary sample type for detecting the BRAF V600E mutation in patients with thyroid nodules, especially with thyroid capsule invasion.

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Dataset Information

Minimizing atelectasis formation during general anaesthesia-oxygen washout is a non-essential supplement to PEEP.

Background

Methods

Results

Conclusion

Publications

Minimizing atelectasis formation during general anaesthesia-oxygen washout is a non-essential supplement to PEEP.

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