week 12 Vascular Emergencies.pdf

DVTs can lead to pulmonary embolism (PE), which is a significant cause of...

DVTs can lead to pulmonary embolism (PE), which is a significant cause of mortality. Why Worry About DVTs? Understanding the difference between a thrombus and an embolus is crucial. Stasis: Any situation where blood is not moving properly, such as prolonged immobilization. Endothelial injury/dysfunction: Surgical procedures (especially orthopedic), Risk Factors (Virchow's Triad) lipid/cholesterol plaque formation. Hypercoagulability: Conditions like pregnancy, diabetes. Pharmaceutical: Low molecular weight heparin (e.g., enoxaparin). Thromboprophylaxis for medical and VTE - Primary Prevention surgical patients: Non-pharmaceutical: Early ambulation, graduated compression stockings, pneumatic compression stockings, adequate hydration. Asymptomatic if incomplete vessel Venous Thromboembolism obstruction. (VTE) - Deep Vein Thrombosis (DVT) Clinical signs and symptoms only 20% accurate. Homan's sign (calf pain at dorsiflexion of the foot) present in less than 1/3 of patients. Pain does not correlate with the size of the Assessment DVT. Limb edema, warmth, erythema, and discoloration may be present. Simplified Wells score and PERC (Pulmonary Embolism Rule-out Criteria) can help assess the probability of VTE. Imaging: Doppler ultrasound, chest imaging (CTPA or V/Q scan). Investigations Bloodwork: FBC, coagulation studies, liver and kidney function, electrolytes, D-dimer. Anticoagulation: Low molecular weight heparin, intravenous unfractionated heparin, warfarin. VTE Treatment Outpatient management is possible for acute DVT in selected patients. Subclavian and carotid arteries supply the arms and brain. Celiac trunk supplies the stomach, duodenum, liver, pancreas, and spleen. Superior mesenteric artery supplies the pancreas, small bowel, and proximal large Aortic Perfusion bowel. Renal arteries supply the kidneys. Inferior mesenteric artery supplies the distal large bowel. Fusiform: Dilation of the entire circumference. Saccular: A portion of the artery is dilated (sac-like appearance), usually the Types of Aortic Aneurysm ascending aorta. Dissecting (pseudoaneurysm): A dissection of the intimal layer creating a false channel or lumen. Atherosclerosis, connective tissue diseases, prior aortic dissection, infection, aortic valve disease, prior aortic surgery, Risk Factors for Developing Aneurysm diabetes, heredity, male gender, and age. Large initial aneurysm diameter, current smoking, elevated blood pressure, higher aortic expansion rate, female sex, and Risk Factors for Rupture presence of symptoms. Aortic Aneurysm Rare under 50 years of age. Prevalence rates estimated at 1.3-8.9% in Abdominal Aortic Aneurysm (AAA) men and 1.0-2.2% in women. Surgical threshold is 5.5 cm for males and 5.0 cm for females. Location and size of the aneurysm determine the signs and symptoms. Possible asymptomatic until rupture. Symptoms may include severe pain Aortic Aneurysm Symptoms (tearing, sharp, ripping), collapse, pulsatile mass, back pain, abdominal pain, cough, dyspnea, stridor, tachycardia, unilateral absence of major pulses, bilateral blood pressure differences, hypertension, hemiplegia, and ischemic limbs. Chest X-ray, MRI, CT scan with contrast, ultrasound, transesophageal Investigations echocardiogram, and angiogram. Vascular Oxygen, large bore IV access, analgesia, tight blood pressure control, treatment of Emergencies hypovolemic shock, and urine output monitoring. Management Surgical repair with graft for ruptured or high-risk aneurysms. Atherosclerotic ulcer leading to intimal tear. Disruption of vasa vasorum causing Mechanism intramural hematoma (very rare). De novo intimal tear. Inherited diseases (connective tissue disorders, family history). Aortic wall stress (hypertension, other Risk Factors cardiovascular risk factors, previous cardiovascular surgery, structural abnormalities, iatrogenic, infection, aortic dilation/aneurysm, 'crack' cocaine). Type A: Starts at the ascending aorta to the left subclavian artery. Types A and B (Stanford Classification) Type B: Starts past the left subclavian Aortic Dissection artery. Chest pain (retrosternal for anterior dissection, interscapular for descending aorta). Symptoms Severe, sudden, and maximal at onset. Other features: Neurological symptoms, syncope, seizure, limb paresthesia, flank pain, shortness of breath, and hemoptysis. History, physical examination, and CT chest with contrast. Pain relief, tight blood pressure control (labetalol, GTN), and correction of Assessment and Management coagulopathy. Surgical repair for Type A, more conservative management for Type B. Acute Limb Ischemia (ALI): Sudden decrease in limb perfusion threatening limb viability within 14 days. Definition and Classification Critical Limb Ischemia (CLI): Occurs over a longer period, with collateral supply often present. Embolic (organic/inorganic substances, arrhythmia, sepsis). Secondary to partial aortic Causes dissection/embolus formation. Iatrogenic. Trauma (crush, laceration). Acute Ischemic Limb Absent pulse distal to occlusion. Presentation Pain, pallor, discoloration, mottling, non- blanching skin, paresthesia, and muscle weakness. Doppler, ultrasound, angiography, and CT Investigations angiography. Damage limitation: Vasodilator therapy, identify and treat the cause, maintain limb position below heart level, analgesia, intravenous thrombolytics, anticoagulation, and surgical intervention. Management Prompt identification and treatment of vascular emergencies are crucial to minimize mortality and morbidity. Conclusion Nurses play a vital role in recognizing these conditions and advocating for timely management.