Sensorineural hearing loss (SNHL) is a type of hearing loss in which the root cause lies in the inner ear or sensory organ (cochlea and associated structures) or the vestibulocochlear nerve (cranial nerve VIII). SNHL accounts for about 90% of reported hearing loss. SNHL is usually permanent and can be mild, moderate, severe, profound, or total. Various other descriptors can be used depending on the shape of the audiogram, such as high frequency, low frequency, U-shaped, notched, peaked, or flat. Sensory hearing loss often occurs as a consequence of damaged or deficient cochlear hair cells. Hair cells may be abnormal at birth or damaged during the lifetime of an individual. There are both external causes of damage, including infection, and ototoxic drugs, as well as intrinsic causes, including genetic mutations. A common cause or exacerbating factor in SNHL is prolonged exposure to environmental noise, or noise-induced hearing loss. Exposure to a single very loud noise such as a gun shot or bomb blast can cause noise-induced hearing loss. Using headphones at high volume over time, or being in loud environments regularly, such as a loud workplace, sporting events, concerts, and using noisy machines can also be a risk for noise-induced hearing loss. Neural, or "retrocochlear", hearing loss occurs because of damage to the cochlear nerve (CVIII). This damage may affect the initiation of the nerve impulse in the cochlear nerve or the transmission of the nerve impulse along the nerve into the brainstem.
A hypertensive urgency is a clinical situation in which blood pressure is very high (e.g., 220/125 mmHg) with minimal or no symptoms, and no signs or symptoms indicating acute organ damage. This contrasts with a hypertensive emergency where severe blood pressure is accompanied by evidence of progressive organ or system damage. Definition
Hypertensive urgency is defined as severely high blood pressure with no evidence of end organ damage. The term "malignant hypertension" was also included under this category with grade III/IV hypertensive retinopathy. However, in 2018, European Society of Cardiology and the European Society of Hypertension issued a new guideline which put "malignant hypertension" under the category "hypertensive emergency", which emphasize on poor outcome if the condition is not treated urgently. Treatment
In a hypertensive urgency blood pressure should be lowered carefully to ≤160/≤100 mmHg over a period of hours to days, this can often be done as an outpatient. There is limited evidence regarding the most appropriate rate of blood pressure reduction, although it is recommended that mean arterial pressure should be lowered by no more than 25 to 30 percent over the first few hours. Recommended medications for hypertensive urgencies include: captopril, labetalol, amlodipine, felodipine, isradipine, and prazosin. Sublingual nifedipine is not recommended in hypertensive urgencies. This is because nifedipine can cause rapid decrease of blood pressure which can precipitate cerebral or cardiac ischemic events. There is also lack of evidence on the benefits of nifedipine in controlling hypertension.