Imaging of suspected pulmonary embolism and deep venous thrombosis in obese patients

Association of medical comorbidities in obese subjects diagnosed with heparin-induced thrombocytopenia

Objectives

Heparin-induced thrombocytopenia can occur in obese subjects. The medical comorbidities associated with obesity may contribute to the pathogenesis of this disease. It is unknown, however, which specific medical comorbidities and if higher odds of thrombosis are present in obese heparin-induced thrombocytopenia patients. We sought to determine whether obese heparin-induced thrombocytopenia subjects had higher odds of both comorbidities and thrombosis, hypothesizing that this patient population would have higher odds of both these conditions.

Methods

This was a multi-center retrospective study utilizing TriNetX©, an electronic health record database, in subjects aged 18-99 years diagnosed with heparin-induced thrombocytopenia. The cohort was divided into two groups (1) non-obese (body mass index < 30 kg/m2) and (2) obese (body mass index ⩾ 30 kg/m2). We evaluated patient characteristics, diagnostic, laboratory, medication, and procedure codes.

Results

A total of 1583 subjects (696 (44.0%) non-obese and 887 (56.0%) obese) were included. Obese subjects had higher odds of diabetes with complications (OR = 1.73, 95% CI = 1.35-2.22, p < 0.001) and without complications (OR = 1.81, 95% CI = 1.47-2.22, p < 0.001). This association was still present after correcting for demographic and clinical factors. There were no increased odds of thrombosis observed in the obesity group.

Conclusions

Our study found that obese heparin-induced thrombocytopenia subjects had higher odds of having a diabetes mellitus comorbidity, but did not have higher odds of thrombosis. Given obesity is considered a hypercoagulable state, further study may be needed to understand why obese subjects diagnosed with heparin-induced thrombocytopenia do not have higher rates of thrombosis.

Critical care for multimorbid patients

Multimorbidity - the simultaneous presence of several chronic diseases - is very common in the critically ill patients. Its prevalence is roughly 40-85 % and continues to increase further. Certain chronic diseases such as diabetes, obesity, chronic heart, pulmonary, liver or kidney disease and malignancy are associated with higher risk of developing serious acute complications and therefore the possible need for intensive care. This review summarizes and discusses selected specifics of critical care for multimorbid patients.

From Dyspnea to Skin Grafting: The Difficulties of Managing a Patient with Extreme Obesity

While the prevalence of severe obesity is increasing worldwide, caregivers are often challenged with the management of patients with extreme weight. A 30-year-old woman (weight 245 kg, body mass index 85 kg/m2) presented with dyspnea, for which investigations led to suspect pulmonary embolism. The patient's weight made it impossible to perform adapted imaging; thus, an empirical anticoagulant treatment was initiated. A hematoma of the thigh occurred as a consequence of a transient antivitamin K overdose, leading to a 15-cm necrotic wound worsened by a state of malnutrition. Multidisciplinary and comprehensive care was performed including wound trimming, antibiotics, skin grafting, treatment of malnutrition, and psychological support, but with marked difficulties due to the lack of adapted medical equipment and facilities as well as appropriate medical guidelines. Overall, 7 months of hospitalization including 4 months of physiotherapy and rehabilitation were needed before the patient could return home. This case highlights how difficult managing patients with extreme obesity can be and points to the importance for healthcare systems to adapt to the specific needs of these patients and to design specific guidelines for treatment dosage and malnutrition prevention and treatment in this setting.

Innovative Technique for Posterior Fixation of Vertically Unstable Pelvic Ring Fracture: A Case Report

An obese 57-year-old woman with known hypertension and diabetes mellitus sustained multiple injuries during an accident, which caused anterior-posterior fracture-dislocation of the pelvic ring. Due to the drawbacks of conventional stabilizing methods for anterior-posterior fracture-dislocations of the hip in this setting, such as the inability to visualize anatomical landmarks fluoroscopically for the iliosacral screw technique and the compromised L5 pedicle preventing lumbopelvic fixation, the patient underwent an innovative Hula Hoop technique described here. Using the Hula Hoop technique, a technique that has rarely been studied in humans, we avoided an invasive open procedure, decreased anesthesia time, reduced the size and number of incisions, and minimized bleeding. After three months of routine physiotherapy and occupational therapy, the patient was able to walk with a walker and an ankle-foot orthosis.

The Impact of Obesity in Critical Illness

The prevalence of obesity is rising worldwide. Adipose tissue exerts anatomic and physiological effects with significant implications for critical illness. Changes in respiratory mechanics cause expiratory flow limitation, atelectasis, and V̇/Q̇ mismatch with resultant hypoxemia. Altered work of breathing and obesity hypoventilation syndrome may cause hypercapnia. Challenging mask ventilation and peri-intubation hypoxemia may complicate intubation. Patients with obesity are at increased risk of ARDS and should receive lung-protective ventilation based on predicted body weight. Increased positive end expiratory pressure (PEEP), coupled with appropriate patient positioning, may overcome the alveolar decruitment and intrinsic PEEP caused by elevated baseline pleural pressure; however, evidence is insufficient regarding the impact of high PEEP strategies on outcomes. Venovenous extracorporeal membrane oxygenation may be safely performed in patients with obesity. Fluid management should account for increased prevalence of chronic heart and kidney disease, expanded blood volume, and elevated acute kidney injury risk. Medication pharmacodynamics and pharmacokinetics may be altered by hydrophobic drug distribution to adipose depots and comorbid liver or kidney disease. Obesity is associated with increased risk of VTE and infection; appropriate dosing of prophylactic anticoagulation and early removal of indwelling catheters may decrease these risks. Obesity is associated with improved critical illness survival in some studies. It is unclear whether this reflects a protective effect or limitations inherent to observational research. Obesity is associated with increased risk of intubation and death in SARS-CoV-2 infection. Ongoing molecular studies of adipose tissue may deepen our understanding of how obesity impacts critical illness pathophysiology.

Canadian Society of Thoracic Radiology/Canadian Association of Radiologists Best Practice Guidance for Investigation of Acute Pulmonary Embolism, Part 2: Technical Issues and Interpretation Pitfalls

The investigation of acute pulmonary embolism is a common task for radiologists in Canada. Technical image quality and reporting quality must be excellent; pulmonary embolism is a life-threatening disease that should not be missed but overdiagnosis and unnecessary treatment should be avoided. The most frequently performed imaging investigation, computed tomography pulmonary angiogram (CTPA), can be limited by poor pulmonary arterial opacification, technical artifacts and interpretative errors. Image quality can be affected by patient factors (such as body habitus, motion artifact and cardiac output), intravenous (IV) contrast protocols (including the timing, rate and volume of IV contrast administration) and common physics artifacts (including beam hardening). Mimics of acute pulmonary embolism can be seen in normal anatomic structures, disease in non-vascular structures and pulmonary artery filling defects not related to acute pulmonary emboli. Understanding these pitfalls can help mitigate error, improve diagnostic quality and optimize patient outcomes. Dual energy computed tomography holds promise to improve imaging diagnosis, particularly in clinical scenarios where routine CTPA may be problematic, including patients with impaired renal function and patients with altered cardiac anatomy.

Obesity in the critically ill: a narrative review

The World Health Organization defines overweight and obesity as the condition where excess or abnormal fat accumulation increases risks to health. The prevalence of obesity is increasing worldwide and is around 20% in ICU patients. Adipose tissue is highly metabolically active, and especially visceral adipose tissue has a deleterious adipocyte secretory profile resulting in insulin resistance and a chronic low-grade inflammatory and procoagulant state. Obesity is strongly linked with chronic diseases such as type 2 diabetes, hypertension, cardiovascular diseases, dyslipidemia, non-alcoholic fatty liver disease, chronic kidney disease, obstructive sleep apnea and hypoventilation syndrome, mood disorders and physical disabilities. In hospitalized and ICU patients and in patients with chronic illnesses, a J-shaped relationship between BMI and mortality has been demonstrated, with overweight and moderate obesity being protective compared with a normal BMI or more severe obesity (the still debated and incompletely understood "obesity paradox"). Despite this protective effect regarding mortality, in the setting of critical illness morbidity is adversely affected with increased risk of respiratory and cardiovascular complications, requiring adapted management. Obesity is associated with increased risk of AKI and infection, may require adapted drug dosing and nutrition and is associated with diagnostic and logistic challenges. In addition, negative attitudes toward obese patients (the social stigma of obesity) affect both health care workers and patients.