Еще одна пилюлька Hескучина

[alex_md]

Давайте посчитаем... Всем полезно вспомнить формулу рассчета инфузии для коррекции гипонатремии.

(Нартий инфузата - натрий сыворотки) / total body water+1

Предположим, что человек весит 80 кг, следовательно TBW = 48 литров

(154-118)/49=0.7 после введение первого литра (ввести в течение часа вполне будет соответствовать рекомендованной скорости коррекции 0.5.

Это будет справедливо при анурии. Как только будет восстановлен объем произойдет некоторая супрессия ADH и пациент начнет выделять более разведенную мочу в большем объеме. При этом альдостерон будет оставаться высоким до тех пор, пока не будет достигнута нормальная осмоляльность. Как считать скорость коррекции дальше, после первых нескольких часов неизвестно. Я пробовал просто контролировать натрий в моче с частотой каждые 2-3 часа, это просто и позволяет точно рассчитать натриевый балланс.

[Alon]

Это все верно. Правда временами рекомендуют добавлять в числитель и К инфузата (это слегка влияет на скорость коррекции в сторону увеличения).
Я пользуюсь и советую использовать программу Medcalc ([Ссылки доступны только зарегистрированным пользователям ]); там одна из формул как раз эта - Change in plasma Na. Очень удобно. Конечно, к формулам в медицине надо относиться с известной осторожностью.
Определение натрия в моче - идея хорошая, но иногда, например, при тубулопатиях не очень-то работает.
Еще раз советую всем заинтересованным лицам прочитать обзоры на обсуждаемую тему , опубликованные в майских 2000 г. номерах NEJM Ссылки даны выше.
Не пожалеете.

[Anton Verbine]

Сообщение от alex_md

... Я пробовал просто контролировать натрий в моче с частотой каждые 2-3 часа, это просто и позволяет точно рассчитать натриевый балланс.

Я несколько раз сталкивался с тем, что формулы не очень точно предсказывали коррекцию- видимо, слишком много допушений, особенно в определении TBW... В итоге, дважды просто контролировал на сыворотки каждый час первые несколько часов, и корректировал инфузию.
...насчет мочи- мне кажется, данные будет еше труднее использовать при рассчетах

[yananshs]

A 31-year-old woman comes to the office with a 5-day history of a red, painful right eye. She complains of photophobia, tearing, and decreased visual acuity and denies any history of trauma. She has had several similar episodes in the past. On examination, her visual acuity is 20/30 in the right eye, both pupils react normally, the conjunctiva is diffusely injected, and there is a watery discharge from the right eye. Fluorescein staining shows uptake in the right cornea, but the cornea is otherwise clear. The left eye is normal. The most likely cause of these findings is
A. acute angle closure glaucoma
B. allergic keratoconjunctivitis
C. bacterial conjunctivitis
D. herpes simplex virus keratitis
E. subconjunctival hemorrhage
Explanation:

The correct answer is D. Herpes simplex keratitis should be suspected in patients with recurrent symptoms of unilateral pain, redness, and photophobia in the presence of an epithelial staining defect. Under slit lamp biomicroscopy these staining defects often take on a "dendritic" appearance, but without a slit lamp they may appear as just fluoroscein uptake. These patients should be referred to an ophthalmologist for treatment. Never prescribe topical corticosteroids for patients with suspected herpes simplex keratitis.

Angle closure glaucoma (choice A) could be consistent with recurrent episodes, but not with this clinical presentation. Patients with angle closure glaucoma will present with poorly reactive pupils, marked decrease in visual acuity, and corneal edema making the cornea unclear.

Allergic diseases (choice B) are most commonly bilateral and are associated with a mucoid discharge and are less likely to cause pain, photophobia, and epithelial defects.

Bacterial conjunctivitis (choice C) rarely produces an epithelial defect, is often associated with copious mucoid discharge, and would not be expected to be recurrent.

Subconjunctival hemorrhage (choice E) is a benign clinical finding. In this case, it would not explain pain, photophobia, tearing, or decreased visual acuity.

[yananshs]

A 23-year-old woman comes into the office because of a 1-week history of painful nodules on her legs. She was recently seen in your office and started on oral contraceptives for the first time. About 2 weeks earlier, she had a "cold" which was associated with sore throat and fever, but she recovered without complications. Physical examination shows multiple red, deep-seated, tender, 2-4 cm nodules on the pretibial region of both legs. She says that "the first lesions" have flattened, leaving a purple or blue-green discoloration. No involvement of the ankles or posterior legs is appreciated. The most appropriate management of her condition is to
A. administer penicillin IM for the presumed upper respiratory infection
B. admit her to the hospital and begin amphotericin for presumed deep fungal infection
C. change her to a different oral contraceptive pill
D. prescribe acetaminophen with codeine
E. recommend ibuprofen 600mg 4 times per day

[Tim Vetrov]

У больной erythema nodosum. Ответ E.

[doctor Asya]

Я тоже считаю, что речь идет об узловатой эритеме. Ответ Е.

[yananshs]

The correct answer is E. Ibuprofen or another nonsteroidal antiinflammatory drug is the treatment of choice for erythema nodosum (EN). EN is a common inflammatory panniculitis which occurs in two forms: acute or chronic. Acute EN most commonly occurs in young adult women with bilateral, symmetrical, deep, tender nodules 1-10 cm in diameter. Usually there are up to 10 lesions but many more may be found. The most common location is the pretibial area. The onset is acute, frequently associated with malaise, leg edema, and arthritis or arthralgias (usually of the ankles, knees or wrists). Over a few days, the lesions flatten, leaving a purple or blue green color resembling a deep bruise. It is commonly associated with a streptococcal infection. Other infectious etiologies have been implied including Mycobacteria tuberculosis, Yersinia, Shigella, Salmonella, or fungal infection. Drugs may also induce erythema nodosum including bromides, iodides, and sulfonamides. The most common drug to induce EN is oral contraceptives. Besides treatment with NSAIDs, if lesions do not resolve within weeks of treatment, physicians should investigate for other infectious causes. Discontinuing oral contraceptive pills may also be important.

Penicillin IM (choice A) is incorrect because treating a respiratory infection without positive culture is not the standard of practice. The proper step here would have been performing a throat culture to determine if Streptococcus is the offending organism prior to initiating treatment

Admit to the hospital to start amphotericin (choice B) is incorrect because deep fungal infection does not usually appear in crops in a healthy, immunocompetent patient. This patient is classic for either streptococcal or drug-induced EN.

Changing oral contraceptive (choice C) is incorrect because most oral contraceptives have been associated with development of EN. Rather than changing to a different type of contraceptive, this patient may be better off discontinuing OCPs.

Acetaminophen with codeine (choice D) is incorrect because only NSAIDs or indomethacin are helpful in EN.

[yananshs]

A 25-year-old comes to the emergency department because of severe right-sided lower abdominal pain for the past 12 hours. She has also experienced fever and chills, but no change in appetite. She is sexually active with 3 different partners and they use the "withdrawal" method for contraception. Her regular menstrual period began 4 days ago. Her temperature is 39 C (102.2 F), blood pressure is 120/80 mm Hg, pulse is 75/min, and respirations are 20/min. Physical examination shows right-sided lower abdominal tenderness with no rebound or guarding. Pelvic examination shows cervical motion tenderness and a purulent discharge. A Gram stain of the discharge shows Gram-negative diplococci within polymorphonuclear leukocytes. A urine pregnancy test is negative. You prescribe a 14-day course ofloxacin and metronidazole. She agrees to be compliant with this therapy and you send her home with a follow-up visit in 48 hours. She returns to the emergency department in 12 hours with one of her sexual partners because of worsening abdominal pain. Her temperature is 39.3 C (102.8 F), blood pressure is 100/60 mm Hg, pulse is 130/min, and respirations are 28/min. Abdominal examination shows severe tenderness with guarding and rebound. At this time you should
A. add cefoxitin to her treatment regimen
B. admit her to the hospital and prepare her for immediate surgery
C. admit her to the hospital for observation
D. evaluate and treat her sexual partner
E. measure the serum Б-subunit of human chorionic gonadotropin concentration
F. order a CT scan of the pelvis

[Anna_Shvedova]

Я за B.
Интересно, конечно, посмотреть на КТ скан, но время не ждет.

[Zambrozy]

Думаю - В

[Tim Vetrov]

Сообщение от yananshs

Physical examination shows right-sided lower abdominal tenderness with no rebound or guarding. Pelvic examination shows cervical motion tenderness and a purulent discharge.

Вообще, странно, что ей сразу не было предложено хотя бы C.
А теперь перитонит, B.

[riltsov]

Гонорея.

Изначально были признаки распространения инфекции на маточные трубы/яичник. Но не было rebound or guarding. Мне кажется, справедливо назначили лечение и отпустили домой. К сожалению, гонорея осложнилась перитонитом.

B. admit her to the hospital and prepare her for immediate surgery

[yananshs]

The correct answer is B. This patient with pelvic inflammatory disease (PID) most likely has a ruptured tuboovarian abscess (TOA), peritoneal inflammation and requires immediate surgery. The abscess needs to be removed before it leads to more severe peritonitis and death.

Adding cefoxitin to her treatment regimen (choice A) is incorrect. In a patient with PID and a TOA you need to make sure that she has effective anaerobic coverage, which she does because she was given metronidazole.

Admitting her to the hospital for observation (choice C) is incorrect because as stated above, she needs immediate surgery because of a TOA.

While it is extremely important to evaluate and treat her sexual partner (choice D), this patient has a ruptured TOA, which is a surgical emergency and requires immediate attention. Evaluating and treating the partner can wait until the proper arrangements are made for this patient.

It is unnecessary to measure the serum Б-subunit of human chorionic gonadotropin concentration (choice E) because her regular menstrual period began a few days ago and a pregnancy test done 12 hours ago was negative.

This patient most likely has a ruptured TOA that requires immediate surgical attention and ordering a CT scan of the pelvis (choice F) will only waste important time.

[yananshs]

A 24-year-old woman with a history of asthma maintained on an albuterol inhaler comes to see you because she has been using her inhaler more frequently over the last few weeks. Previously she used her inhaler about once a week but she now finds that she is using it every day. She denies any fever or shortness of breath, but has an occasional nonproductive cough. She has not experienced any change in her environment and denies any sick contacts. She does not smoke, drink, or use injection drugs. Her temperature is 37.0 C (98.6 F) and her peak flow is 350cc (normal for her 400cc.) Her throat is clear and she has some mild wheezing on expiration. The most appropriate next step in management is to
A. give her a 5-day course of azithromycin
B. increase the dose of albuterol
C. obtain a chest x-ray
D. start inhaled steroids and instruct her in their use
E. start oral theophylline therapy