complex sleep-related behaviors

Q: 32 years old male is brought to the ED after a Motor Vehicle Accident (MVA). Patient does not remember driving. Per his wife, he went to bed normally, but she was awakened with a police call that her husband was in an MVA on highway. The patient was found by police at the accident site behind a vehicle, only in night gown without any shoes or slippers. Patient remembered the last thing going to bed at his home. Patient acknowledges that recently he increased his sleep medicine by himself. The patient was diagnosed with complex sleep-related behaviors. What are the few complex sleep-related behaviors with insomnia meds?

Answer:

Complex sleep-related behaviors are common and very underappreciated. They are common with higher doses of all insomnia meds, but the most described culprits are

• zolpidem
• zaleplon
• eszopiclone
• triazolam

Patients may perform various activities outside of their will and may be potentially fatal (like our patient in the above case). Common activities while not awake are

• sleepwalking
• driving
• phone call
• eating
• sex 
• swimming

Interestingly, young people are prone to such incidents more than elderly people.

#sleep

#pharmacology

#psychiatry

References:

1. US Food and Drug Administration (FDA). FDA adds boxed warning for risk of serious injuries caused by sleepwalking with certain prescription insomnia medicines. FDA Drug Safety Communication, April 30, 2019. Available at: https://www.fda.gov/drugs/drug-safety-and-availability/fda-adds-boxed-warning-risk-serious-injuries-caused-sleepwalking-certain-prescription-insomnia (Accessed on March 31, 2025).

2. Chen CS, Huang MF, Hwang TJ, et al. Clinical correlates of zolpidem-associated complex sleep-related behaviors: age effect. J Clin Psychiatry 2014; 75:e1314.

3. Chen LF, Lin CE, Chou YC, et al. A comparison of complex sleep behaviors with two short-acting Z-hypnosedative drugs in nonpsychotic patients. Neuropsychiatr Dis Treat 2013; 9:1159.

4. Tsai JH, Yang P, Chen CC, et al. Zolpidem-induced amnesia and somnambulism: rare occurrences? Eur Neuropsychopharmacol 2009; 19:74.

5. Hwang TJ, Ni HC, Chen HC, et al. Risk predictors for hypnosedative-related complex sleep behaviors: a retrospective, cross-sectional pilot study. J Clin Psychiatry 2010; 71:1331.

equi-osmolarity of Mannitol vs. Salt bomb

Q: In the treatment of increased intracranial pressure (ICP), what is the equivalency of 23.4% of NaCl and Mannitol in terms of similar osmolar effect?

Answer: To be precise, 0.686 ml of 23.4% NaCl is equiosmolar to 1 gram/kg of 20% mannitol in effect. 

The usual dose is 30-50 ml of 23.4% NaCl or 50-70 grams of mannitol q3-q6 hours as needed. Dose can be adjusted per clinical situation and lab osmolarity findings.

#neurology

#pharmacology

References:

1. Ch. Lazaridis, R. Neyens, J. Bodle - High-osmolality saline in neurocritical care systematic review and meta-analysis - Crit Care Med, 41 (2013), pp. 1353-1360

2. Gisela Llorente, Maria Claudia Niño de Mejia, Mannitol versus hypertonic saline solution in neuroanaesthesia, Colombian Journal of Anesthesiology, Volume 43, Supplement 1, 2015, Pages 29-39,

ISSN 2256-2087, https://doi.org/10.1016/j.rcae.2014.07.010. (https://www.sciencedirect.com/science/article/pii/S2256208714000935)

Renal cyst and potassium

Case: 62 years old male presented to ED with flank pain and accelerated hypertension (HTN). He informed that his primary care doctor recently found him to have late-onset HTN. In the last few months, he has continued to have potassium issues in his lab work for no reason. The only positive finding so far, is a simple renal cyst on abdominal ultrasound, regarded as an incidental finding by the radiologist. If a simple cyst of the kidney becomes symptomatic, it tends to cause? - Select one

A) hyperkalemia

B) hypokalemia

Answer: B

The finding of a renal cyst on ultrasound is usually benign and an incidental finding. But, if it enlarges in size, it may become a cause of late-onset hypertension. The reason is persistent pain, discomfort, and possible excess renin secretion. This should be treated as secondary HTN, which many times presents as an acute rise in blood pressure in a normotensive person. 

These patients tend to have persistent hypokalemia, which remains unexplained due to any other cause.

#nephrology

#electrolytes

References:

1. Ferrari P. The challenge of renal cystic disease and its association with hypertension, age and abnormal potassium handling. J Hypertens. 2007 Jul;25(7):1347-9. doi: 10.1097/HJH.0b013e32814db544. PMID: 17563553.

2. Gamakaranage CS, Rodrigo C, Jayasinghe S, Rajapakse S. Hypokalemic paralysis associated with cystic disease of the kidney: case report. BMC Nephrol. 2011 Apr 18;12:16. doi: 10.1186/1471-2369-12-16. PMID: 21501478; PMCID: PMC3095547.

BP from lower extremities

Q: Blood Pressure (BP) obtained from the lower extremity is usually _______________ than the BP obtained from the arm? - select one

A) higher

B) lower

Answer: A

Although undesirable, BP from the lower extremities can be obtained if needed, particularly in End-Stage Renal Disease (ESRD) patients with vascular fistulae. Patients with a known history of coarctation of the aorta may also require that.

Systolic blood pressure in the lower extremity is usually higher than in the upper extremity (measured from the brachial artery). This is true for both the calf and the ankle. On an average, the difference is about 10 mmHg higher in the calf and 17 mmHg higher in the ankle.

While obtaining BP in the lower extremity, the cuff center should align with the popliteal artery. 

#cardiology

#procedures

References:

1. Sheppard JP, Lacy P, Lewis PS, Martin U; Blood Pressure Measurement Working Party of the British and Irish Hypertension Society. Measurement of blood pressure in the leg-a statement on behalf of the British and Irish Hypertension Society. J Hum Hypertens. 2020 Jun;34(6):418-419. doi: 10.1038/s41371-020-0325-5. Epub 2020 Apr 22. PMID: 32322006; PMCID: PMC7299841.

2. McDonagh STJ, Sheppard JP, Warren FC, Boddy K, Farmer L, Shore H, Williams P, Lewis PS, Baumber R, Fordham J, Martin U, Aboyans V, Clark CE; INTERPRESS-IPD Collaborators. Arm Based on LEg blood pressures (ABLE-BP): can systolic leg blood pressure measurements predict systolic brachial blood pressure? Protocol for an individual participant data meta-analysis from the INTERPRESS-IPD Collaboration. BMJ Open. 2021 Mar 19;11(3):e040481. doi: 10.1136/bmjopen-2020-040481. PMID: 33741659; PMCID: PMC7986760.

SJS/TEN and Na

Q: Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN) usually causes? - select one

A) hypernatremic dehydration

B) hyponatremic dehydration

Answer: B

Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN) is a serious and potentially fatal mucocutaneous drug reaction, characterized by extensive necrosis and detachment of the epidermis due to massive keratinocyte apoptosis. It usually starts as a prodrome of fever and influenza-like symptoms followed in one to three days by an eruption of ill-defined, coalescing, erythematous macules with atypical target lesions. As the disease progresses, vesicles and bullae form, and the skin begins to slough within days. Mucosal involvement occurs in over 90 percent of cases.

Morbidity (and mortality) occurs due to massive loss of fluids, electrolyte imbalance, hypovolemic shock with hyponatremic dehydration, sepsis, and multiple system organ failure (MSOF). These patients are usually managed in a burn unit because of extensive skin detachment. 

#dermatology

References:

1. Hung CC, Liu WC, Kuo MC, Lee CH, Hwang SJ, Chen HC. Acute renal failure and its risk factors in Stevens-Johnson syndrome and toxic epidermal necrolysis. Am J Nephrol. 2009;29(6):633-8. doi: 10.1159/000195632. Epub 2009 Jan 21. PMID: 19155617.

2. Huang SC, Tsai SJ. Hyponatremia and Stevens-Johnson syndrome in a patient receiving carbamazepine. Gen Hosp Psychiatry. 1995 Nov;17(6):458-60. doi: 10.1016/0163-8343(95)90049-7. PMID: 8714810.

3. Shah H, Parisi R, Mukherjee E, Phillips EJ, Dodiuk-Gad RP. Update on Stevens-Johnson Syndrome and Toxic Epidermal Necrolysis: Diagnosis and Management. Am J Clin Dermatol. 2024 Nov;25(6):891-908. doi: 10.1007/s40257-024-00889-6. Epub 2024 Sep 15. PMID: 39278968; PMCID: PMC11511757.