New York Times Magazine, Dec 4, 2022 (I)

choi

(1) Lisa Sanders, Daddy Longlegs. When he stood up quickly, he got dizzy and sometimes fainted. Doctors gave a name for this -- they just dodn't know what caused it. At page 22,
https://www.nytimes.com/2022/11/ ... sion-diagnosis.html

Quote:

"Years before, the patient had fallen in the bathtub, broken his ribs and punctured a lung. Blood filled his chest and collapsed the lung [accumulation of much blood might squeeze the lung but more commonly, broken rib(s) punctured lung, causing the latter to collapse and ensuing breathlessness; broken rib itself causes severe pain]. He had to be rushed to the hospital. Patients who are stuck in bed while in the hospital are at risk of developing blood clots in the veins of their legs [medical term: deep vain thrombosis (DVT)] because they are immobilized. Clots form when blood isn't moving. These patients are usually started on blood thinners to reduce that risk. Because this man had bled into his chest, blood thinners weren't a good option for him. Clots that form because of immobility block veins and cause swelling and pain [because venous blood can not return to heart efficiently but need to use alternate, superficial, small-calibered veins\, but they can also be deadly if they [a thrombus is dislodged and becomes, be definition, an embolus] travel through the body and end up in the lungs or brain [wrong: embolus from leg vein can NOT reach brain because capillary network in lungs filter the embolus out]. So his doctors had chosen to put a filter in the main vein that brought blood from his legs back to his heart — a vessel called the inferior vena cava — to catch any clots that formed and broke free.  These filters are supposed to be removed a few months later when the risk of clotting goes down, but many are not removed on schedule. This one had been left in place for more than 15 years.

"to get the filter out [of inferior vena cava]. * * * The patient was sedated for the operation. [doctor] put a tiny tube [called catheter] through an incision into the patient's jugular vein in his neck and slowly advanced it down [via superior vena cava] past the heart into the [inferior] vena cava where the filter was located. These contraptions look like daddy longlegs with tiny hooks at each foot to hold them in place in the vein. Where the body of the insect would be located was a small hook. [doctor] used a tiny gripping tool to grasp the hook and pull the filter up through the vena cava and out through the small incision in the patient's neck. Next Parkhurst inserted tiny [first deflated] balloons [backed by a stiff metal rod] that he inflated [to create volume] to reopen the threadlike [(venous) blood] stream through the narrowed vena cava. He then positioned a stent to hold the vessel open [which is the purpose of a stent]. He continued this process down the primary vein of each leg [balloons and stents, to increase (venous) blood flow of deep veins in legs]. The procedure took six hours and required nine stents, but finally there was good blood flow between the legs and the heart.

Note:
(a)
(i) The article is straightforward: "When he stood up quickly, he got dizzy." The diagnosis is positional hypotension -- or, in fanciful jargon, "orthostatic hypotension (O.H.)" as the text of the article indicates *you do not have to remember this, because this fanciful term is not used in medicine, either).
(ii) There is nothing important in this article, except the vena cava filter called by the author as spider-like. See quotation 2 and (c) below.
(iii) Dr Sanders's failure in this article is not to explain why many veins in this patient were almost completely clogged. By what?  The filter itself would not obstruct blood flow.

(b) daddy longlegs
https://en.wikipedia.org/wiki/Daddy_longlegs
(may refer to: "Pholcidae or cellar spiders, a family of spiders" which neither produces venom nor gave fangs)

(c)
(i) Inferior Vena Cava Filters. Center for Vein Care, Stony Brook Medicine, undated
https://vein.stonybrookmedicine. ... r-vena-cava-filters
(ii) Stony Brook University Hospital
https://en.wikipedia.org/wiki/Stony_Brook_University_Hospital
(1980- ; located in Hamlet of Stony Brook, New York; section 2 About, section 2.1 Education: Renaissance School of Medicine at Stony Brook University (Renaissance is a hedge fund)
(iii)
(A) vein
https://en.wikipedia.org/wiki/Vein

Take notice that pulmonary artery leaving heart (for lungs) carries venous blood, whereas pulmonary vein carries arterial or oxygenated blood back to heart from lungs.
(B) inferior vena cava  下腔静脉
https://en.wikipedia.org/wiki/Inferior_vena_cava
("The name derives from Latin: [noun feminine] vena, 'vein,' [adjective masculine; feminine  cava] cavus, 'hollow' ")


(d)
(i) Thrombosis (forming thrombus) in deep vein(s) of legs is rare among Asians in Asia and in the West after emigration -- about one fifth to one sixth of the chance compared with whites or blacks in the West. Thrombosis  dee vein of a leg hinders (venous) blood return to heart. However, the danger is when a thrombus get detached and turns an embolus, which flow with blood back to right side of the heart and enter pulmonary artery and blocks f=bolld flow there (patient dies instantly). If the embolus is smaller in size, it is lodged somewhere downstream in the arterial side of a lung.  
(ii) The following four items are from medicine. There is no need to read the rest, beyond quotations.
(A) Wang, Kang-Ling et al, The Diagnosis and Treatment of Venous Thromboembolism in Asian Patients. Thrombosis Journal, vol 16 (2018)
https://thrombosisjournal.biomed ... 6/s12959-017-0155-z

Quote:

"Venous thromboembolism (VTE), which includes deep vein thrombosis (DVT) and pulmonary embolism (PE) * * *

"studies conducted in Asia have consistently reported lower rates of VTE in Asian populations than in Caucasians (Table 1). These data are comparable to those obtained from Asian patients in Western countries * ** " (footnotes omitted).

(B) LEE Lai Heng et al, Incidence of Venous Thromboembolism in Asian Populations: A Systematic Review. Thrombosis and Haemostasis, 117: 2243 (2017)
https://pubmed.ncbi.nlm.nih.gov/29212112/
("Conclusion: Population-wide incidence estimates in Asia were approximately 15 to 20% of the levels recorded in western countries")
(C) WAHEED Sheikh M et al, Deep Vein Thrombosis. StatPearls, last update Aug 11, 2021
https://www.ncbi.nlm.nih.gov/books/NBK507708/
("A deep-vein thrombosis (DVT) is a blood clot that forms within the deep veins, usually of the leg, but can occur in the veins of the arms and the mesenteric and cerebral veins. * * * the annual incidence of DVT is 80 cases per 100,000 [in the West] * * * There is evidence from the United States that there is an increased incidence of DVT and an increased risk of complications in African Americans and white people when compared to Hispanics and Asians. * * * [symptoms:] • Pain (50% of patients), • Red [and hot skin, with dilated superficial veins], • Swelling (70% of patients) * * *
The focus is on the prevention of DVT [: importance of ambulation, compression stockings (the first two to prevent stasis of venous blood], and anticoagulation medications] * * * Once DVT is diagnosed, the treatment is with an anticoagulant for 3-6 months")
(D) VYAS Vrinda and GOYAL Amandeep, Acute Pulmonary Embolism. StatPearls, last update Aug 8, 2022
https://www.ncbi.nlm.nih.gov/books/NBK560551/
("Most pulmonary embolisms originate as lower extremity DVTs. * * * After coronary artery disease [causing myocardial infarction] and stroke, acute pulmonary embolism is the third most common type of cardiovascular disease. * * * PE leads to impaired gas exchange due to obstruction of the pulmonary vascular bed leading to a mismatch in the ventilation to perfusion ratio because alveolar ventilation remains the same, but pulmonary capillary blood flow decreases, effectively leading to dead space ventilation and hypoxemia. * * * The most common symptoms of PE include the following: dyspnea [Ancient Greek for breathlessness], pleuritic chest pain, cough, hemoptysis, presyncope, or syncope [Ancient Greek for fainting; e is pronounced like the vowel of hit]. * * * Vena Cava Filters[:] These block the path of travel of emboli and prevent them from entering the pulmonary circulation. Filters are indicated in patients with venous thromboembolism who have an absolute contraindication to anticoagulants, and in patients with recurrent VTE despite anticoagulation. Retrievable filters are preferred, such that once the contraindication has resolved, the filter can be removed")