Refractory Hypoxemia in a Patient with Submassive Pulmonary Embolism and an Intracardiac Shunt: A Case Report and Review of the Literature

CT imaging determinants of persistent hypoxemia in acute intermediate-risk pulmonary embolism

The factors associated with persistent hypoxemia after pulmonary embolus (PE) are not well understood. Predicting the need for oxygen post discharge at the time of diagnosis using available CT imaging will enable better discharge planning. To examine the relationship between CT derived imaging markers (automated computation of arterial small vessel fraction, pulmonary artery diameter to aortic diameter ratio (PA:A), right to left ventricular diameter ratio (RV:LV) and new oxygen requirement at the time of discharge in patients diagnosed with acute intermediate-risk PE. CT measurements were obtained in a retrospective cohort of patients with acute-intermediate risk PE admitted to Brigham and Women's Hospital between 2009 and 2017. Twenty one patients without a history of lung disease requiring home oxygen and 682 patients without discharge oxygen requirements were identified. There was an increased median PA:A ratio (0.98 vs. 0.92, p = 0.02) and arterial small vessel fraction (0.32 vs. 0.39, p = 0.001) in the oxygen-requiring group], but no difference in the median RV:LV ratio (1.20 vs. 1.20, p = 0.74). Being in the upper quantile for the arterial small vessel fraction was associated with decreased odds of oxygen requirement (OR 0.30 [0.10-0.78], p = 0.02). Loss of arterial small vessel volume as measured by arterial small vessel fraction and an increase in the PA:A ratio at the time of diagnosis were associated with the presence of persistent hypoxemia on discharge in acute intermediate-risk PE.

Percutaneous stent implantation for occluded central shunts in adults: A case report and review of current evidence

Background

Patients with cyanotic complex congenital heart defects (CHDs) commonly undergo palliation with interposition of systemic-to-pulmonary shunts (SPSs). These palliative shunts are rarely found in adults with CHDs and can be complicated with progressive obstruction or total occlusion during follow-up. The best treatment option for shunt re-permeabilization is challenging and case-oriented because most patients are high risk candidates for redo surgeries. We aimed to review the current evidence on percutaneous stent implantation to treat failed SPSs.

Methods

We performed a comprehensive literature review on percutaneous stent implantation to treat failed and occluded SPSs. We also reported the case of a 33-year-old man with cyanotic CHD and a occluded central aorto-pulmonary shunt, who was successfully treated with percutaneous balloon dilatation and subsequently stent implantation at our institution.

Result

We identified and included 31 articles reporting on 150 patients and 165 stent implantations in failed SPSs. The age of patients at the time of stent implantation ranged from 6 days to 47 years. The time between the surgical shunt creation and transcatheter intervention ranged from 1 day to 17 years. Overall, 161/165 (97.5%) stent implantations were successful. The most common clinical presentation was cyanosis and decreased atrial oxygen saturations and the indication for stent implantation was shunt obstruction and stenosis.

Conclusion

This review highlights the benefits of endovascular stenting to permeabilize failed SPSs in children and adults with complex CHD who are classified as poor candidates for re-surgical repair.

Outcomes of Surgical and Mechanical Thrombectomy in Massive Saddle Pulmonary Embolism: A National Perspective

Introduction Saddle pulmonary embolism (PE) is a type of central PE that involves the bifurcation of the pulmonary arteries. First-line treatment is usually systemic thrombolytics, but surgical and mechanical thrombectomy (ST and MT) are used for patients with contraindications to thrombolytics or right heart strain. This study compares surgical and mechanical thrombectomy trends and outcomes in patients with saddle PE. Methods The data was extracted from the National In-Patient Sample (NIS) from 2016-2018 using the International Classification of Diseases-10-Clinical Modification (ICD-10-CM) diagnosis codes. We used the Cochrane-Armitage trend test to analyze the trends of ST and MT and the chi-square test for statistical analyses. A two-tailed p-value of <0.05 was considered statistically significant. Results The overall trend of MT in saddle PE rose from 2016 to 2018, while ST remained stable. Around 95% of patients undergoing ST/MT were emergent admissions, with 82.5% occurring in teaching hospitals. Patients of age >65 years and more with comorbidity burdens were more likely to undergo MT over ST. In-hospital mortality after ST was 15.1%, and after MT was 11.1% (p:<0.001). The most common complications after ST were congestive heart failure (CHF) and atrial fibrillation (AF), and after MT were vascular events and CHF. Conclusion The use of mechanical thrombectomy has steadily increased during the study period. ST is more common in large/teaching hospitals, weekend admissions, and patients transferred from other facilities. MT is more common in elderly patients with a higher comorbidity burden. Patients who underwent MT had lower mortality, length of hospital stay, and post-procedural complications.

Evidence-based perioperative diagnosis and management of pulmonary embolism: A systematic review

Background

The diagnosis and treatment of pulmonary embolism have multi-modal approach based on specificity, sensitivity, availability of the machine, and associated risks of imaging modalities.

Aim

This review aimed to provide shreds of evidence that improve perioperative diagnosis and management of suspected pulmonary embolism.

Methods

The study was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline 2020. After a clear criteria has been established an electronic searching database was conducted using PubMed, Google Scholar, Cochrane library, and Cumulative Index of Nursing and Allied Health Literature (CINAHL), with Key search terms included:('pulmonary embolism' AND' anesthesia management ', 'anticoagulation' AND 'pulmonary embolism', 'thrombolysis 'AND 'pulmonary embolism', 'surgery' AND' pulmonary embolism'), were used to draw the evidence.The quality of literatures were categorized based on WHO 2011 level of evidence and degree of recommendation, in addition, the study is registered with research registry unique identifying number (UIN) of reviewregistry1318." and has high quality based on AMSTAR2 assessment criteria.

Results

A totally of 27 articles were included [guidelines (n = 3), Cochrane (=5), systemic reviews (n = 7), meta-analyses (=2), RCT (n = 4), cohort studies (n = 3), and cross-sectional study (n = 3) and illegible articles identified from searches of the electronic databases were imported into the ENDNOTE software version X7.1 and duplicates were removed.

Discussion

Currently divergent and contradictory approaches are implemented in diagnosis and management for patients suspected of pulmonary embolism.

Conclusion

All perioperative patients, especially trauma victims, prostate or orthopedic surgery, malignancy, immobility, and obesity; smokers; and oral contraceptive users, antipsychotic medications are at increased risk of venous thromboembolism and need special caution during surgery and anesthesia.

An unusual case of persisting hypoxia in a patient with a thrombolysed pulmonary embolism

Exertional breathlessness and hypoxia are common presenting complaints in acute medicine. We describe a case where the patient continued to have persistent hypoxia even after the primary cause (pulmonary embolism) was diagnosed and treated. The hypoxia persisted as an enigma, its cause remaining elusive till diagnosed. Standard first-line investigations would not have reached the underlying diagnosis in this case and, as such, it demonstrates the keen clinical sense and complex investigative strategy required to solve the puzzle.