Postoperative acute respiratory dysfunction and the influence of antibiotics after acute type A aortic dissection surgery: A retrospective analysis

Management of acute aortic dissection in critical care

Aortic dissections are associated with significant mortality and morbidity, with rapid treatment paramount. They are caused by a tear in the intimal lining of the aorta that extends into the media of the wall. Blood flow through this tear leads to the formation of a false passage bordered by the inner and outer layers of the media. Their diagnosis is challenging, with most deaths caused by aortic dissection diagnosed at post-mortem. Aortic dissections are classified by location and chronicity, with management strategies depending on the nature of the dissection. The Stanford method splits aortic dissections into type A and B, with type A dissections involving the ascending aorta. De Bakey classifies dissections into I, II or III depending on their origin and involvement and degree of extension. The key to diagnosis is early suspicion, appropriate imaging and rapid initiation of treatment. Treatment focuses on initial resuscitation, transfer (if possible and required) to a suitable specialist centre, strict blood pressure and heart rate control and potentially surgical intervention depending on the type and complexity of the dissection. Effective post-operative care is extremely important, with awareness of potential post-operative complications and a multi-disciplinary rehabilitation approach required. In this review article we will discuss the aetiology and classifications of aortic dissection, their diagnosis and treatment principles relevant to critical care. Critical care clinicians play a key part in all these steps, from diagnosis through to post-operative care, and thus a thorough understanding is vital.

Association of preoperative monocyte/lymphocyte ratio with postoperative oxygenation impairment in patients with acute aortic syndrome

BACKGROUND

Postoperative oxygenation impairment represents a common complication in patients with the acute aortic syndrome (AAS). The study aimed to explore the relationship between inflammatory indicators and AAS patients with oxygenation impairment after operation.

METHODS

In this study, 330 AAS patients who underwent surgery were enrolled and divided into 2 groups based on postoperative oxygenation impairment (non-oxygenation impairment group and oxygenation impairment group). Regression analysis was performed to assess the relationship between inflammatory indicators and postoperative oxygenation impairment. A smooth curve and interaction analysis were further conducted. Stratified analysis was used according to preoperative monocyte/lymphocyte ratio (MLR) (Tertiles).

RESULTS

Multivariate analysis showed that preoperative MLR was independently related to oxygenation impairment after surgery in AAS patients (OR, 95% CI, P: 2.77, 1.10-7.00, 0.031). The smooth curve indicated the risk of postoperative oxygenation impairment was higher with the elevated preoperative MLR. Interaction analysis revealed that patients with AAS with high preoperative MLR who had coronary artery disease (CAD) had a higher risk of oxygenation impairment after operation. Moreover, stratified analysis was performed according to baseline MLR (Tertiles), and a higher baseline MLR level in AAS patients was correlated with a lower arterial oxygen tension (P_aO2) / inspiratory oxygen fraction (F_iO2) ratio perioperatively.

CONCLUSIONS

In AAS patients, preoperative MLR level was independently related to postoperative oxygenation impairment.

Perioperative Risk Factors for Post-operative Pneumonia after Type A Acute Aortic Dissection Surgery

OBJECTIVE

Type A acute aortic dissection (TAAAD) is a dangerous and complicated condition with a high death rate before hospital treatment. Patients who are fortunate to receive prompt surgical treatment still face high in-hospital mortality. A series of post-operative complications further affects the prognosis. Post-operative pneumonia (POP) also leads to great morbidity and mortality. This study aimed to identify the prevalence as well as the risk factors for POP in TAAAD patients and offer references for clinical decisions to further improve the prognosis of patients who survived the surgical procedure.

METHODS

The study enrolled 89 TAAAD patients who underwent surgical treatment in Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei province, China from December 2020 to July 2021 and analyzed the perioperative data and outcomes of these patients. Logistic regression analyses were used to identify the risk factors for POP.

RESULTS

In the study, 31.5% of patients developed POP. Patients with POP had higher proportions of severe oxygenation damage, pneumothorax, reintubation, tracheotomy, renal replacement therapy, arrhythmia, gastrointestinal bleeding, and longer duration of mechanical ventilation, fever, ICU stay, and length of stay (all with P<0.05). The in-hospital mortality was 2.3%. Smoking, preoperative white blood cells, and intraoperative transfusion were the independent risk factors for POP in TAAAD.

CONCLUSION

Patients who underwent TAAAD surgery suffered poorer outcomes when they developed POP. Furthermore, patients with risk factors should be treated with caution.

Impact of body mass index on postoperative oxygenation impairment in patients with acute aortic syndrome

Objective: Oxygenation impairment is a common complication of acute aortic syndrome (AAS) patients after surgical repair. The aim of this study is to identify the relationship between body mass index (BMI) and the risk of postoperative oxygenation impairment in AAS patients.

Methods: A total of 227 consecutive patients who were diagnosed as AAS and underwent surgical repair were recruited. They were divided into two groups based on the postoperative oxygenation impairment (non-oxygenation impairment group and oxygenation impairment group). Logistic regression was conducted to evaluate the association between BMI and the risk of oxygenation impairment after surgery. Dose-response curve and subgroup analysis were used to test the reliability of the results of regression analysis. A meta-analysis was then performed to further confirm these results using Pubmed, Embase, and Web of Science databases.

Results: For the retrospective study, a significant association was observed after adjusting for a series of variables. BMI was significantly correlated with postoperative oxygenation impairment in patients with AAS (OR, 95% CI, P: 1.27, 1.17–1.46, 0.001). Compared with the normal weight group (18.5 kg/m² ≤ BMI <23.0 kg/m²), patients with excessive BMI were at a higher risk of oxygenation impairment for the overweight group (23.0 kg/m² ≤ BMI <25 kg/m²) and obesity group (BMI ≥25 kg/m²) (OR, 95% CI, P: 4.96, 1.62–15.15, 0.005; 9.51, 3.06–29.57, <0.001). The dose-response curve showed that the risk of oxygenation impairment after surgery increased with the increased BMI. Besides, subgroup analysis showed that AAS patients who have an excess weight with a TNF-α ≥ 8.1 pg/ml carried an excess risk of postoperative oxygenation impairment. For the meta-analysis, the pooled result also indicated that AAS patients with high BMI had a significantly increased risk of oxygenation impairment after surgery (OR, 95% CI, P: 1.40, 1.18–1.66, 0.001).

Conclusion: Excessive BMI was an independent risk factor for AAS with postoperative oxygenation impairment.

Age-dependent differences in the prognostic relevance of body composition-related variables in type A aortic dissection patients

Background

The current research is allocated to appraise the association between the parameters of body composition and findings in type A aortic dissection (TAAD) cases in diverse age groups.

Methods

Data from consecutive TAAD patients undergoing implantation of modified triple-branched stent-graft from January 2017 and December 2019 were prospectively collected and analyzed. A regression model of Cox proportional hazard was employed to assess correlations among body composition-related variables (body mass index [BMI], lean body mass [LBM], body surface area [BSA], and LBM index) as well as cumulative mortality.

Results

Overall, 258 patients (53.9 ± 11.1 years old; 72.9% male) were separated into young (n = 110) and elderly (n = 148) age groups based upon whether they were younger or older than 50 years of age. Of these patients, 247 survivors were included in subsequent analyses over an average 26.8 ± 11.6 month follow-up duration. Multivariate analyses in the elderly group instead of young group indicated that increased BMI (p = 0.042), BMI ≤ 18.5 kg/m² (p = 0.025), and lower LBM index values (p = 0.019) were significant predictors of increased total all-cause cumulative mortality. BMI was considerably positively correlated with estimated all-cause cumulative mortality in elderly but not young TAAD cases.

Conclusion

Briefly, these results suggest that BMI and LBM indices are only significant predictors of TAAD patient all-cause mortality in elderly patient cohorts, whereas they do not offer significant prognostic value for younger patients. As such, these age differences must be taken into consideration when conducting stratified risk assessments based upon TAAD patient body composition characteristics.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13019-021-01742-1.