Saline, hypertonic

Osmotherapy employs agents such as mannitol, glycerol, and hypertonic saline to create an osmotic gradient between the brain (optimally, the edematous infarcted tissue) and the bloodstream, such that water is drawn out from the brain, thereby reducing edema. Each of these agents has been shown to be effective, and may be used alone or in combination with a diuretic, such as furosemide. Their action, however, depends upon an intact blood-brain barrier (BBB), and concerns have been raised for possible paradoxical worsening when one is absent. In this hypothesis, mannitol extravasates from the vessel into the interstitial tissue and water follows a new osmotic... 

Hypertonic sahne is actively excluded from an intact BBB and also acts to draw water into the intravascular space by the creation of a sodium gradient. Various concentrations have been evaluated, with continuous sodium chloride infusions ranging from 3% to 9%, and bolus infusions up to 23.4% administered over 20 minutes in a 30 mL solution. When a continuous infusion is used, the serum sodium is typically titrated to the 155-160 range. Sodium levels above this range raise the concern for seizures and other toxic side effects. Hypertonic saline may hold an advantage over mannitol, as it has been found in animal models to decrease edema in both... 

Schwarz S, Schwab S, Bertram M, Aschoff A, Hacke W. Effects of hypertonic saline hydroxyethyl starch solution and mannitol in patients with increased intracranial pressure after stroke. Stroke 1998 29(8) 1550-1555. 

Qureshi A, Suarez JI. Use of hypertonic saline solutions in treatment of cerebral edema and intracranial hypertension. Crit Care Med 2000 28(9) 3301-3313. 

Dornase alfa (Pulmozyme ) is a recombinant human (rh) DNase that selectively cleaves extracellular deoxyribonucleic acid (DNA). This DNA is released during neutrophil degradation and contributes to the high viscosity of CF sputum. Nebulization of dornase alfa 2.5 mg once or twice daily improves daily pulmonary symptoms and function, reduces pulmonary exacerbations, and improves quality of life.16 N-acetylcysteine and hypertonic saline are other mucolytic agents that are occasionally used however, they are not preferred agents due to a greater incidence of bronchospasm and unpleasant odor and taste.5... 

Therapeutic fluids include crystalloid and colloid solutions. The most commonly used crystalloids include normal saline, hypertonic saline, and lactated Ringer s solution. Examples of colloids include albumin, the dextrans, hetastarch, and fresh frozen plasma. 

Fluids can be classified further according to their tonicity. Isotonic solutions (i.e., normal saline or 0.9% sodium chloride [NaCl]) have a tonicity equal to that of the ICF (approximately 310 mEq/L or 310 mmol/L) and do not shift the distribution of water between the ECF and the ICF. Because hypertonic solutions (i.e., hypertonic saline or 3% NaCl) have greater tonicity than the ICF (greater than 376 mEq/L or 376 mmol/L), they draw water from the ICF into the ECF. In contrast, hypotonic solutions (i.e., 0.45% NaCl) have less tonicity than the ICF (less than 250 mEq/L or 250 mmol/L) leading to an osmotic pressure gradient that pulls water from the ECF into the ICF. The tonicity, electrolyte content, and glucose content of selected fluids are shown in Table 24—3. 

Hypertonic saline is obviously hypertonic and provides a significant sodium load to the intravascular space. This solution is utilized very infrequently given the potential to cause significant shifts in the water balance between the ECF and the ICF. It is typically considered to treat patients with severe hyponatremia who have symptoms attributable to low serum sodium. 

Although both water and sodium are required in this instance, sodium needs to be provided in excess of water to fully correct this abnormality. As such, hypertonic saline (3% NaCl) is often used. One can estimate the change in serum sodium concentration after 1 L of 3% NaCl infusion using the following equation 16... 

Treatment of hyponatremia involves the use of hypertonic saline. However, care is required since correction at rates in excess of 1 mEq/l/h may result in central pontine myelinolysis (CPM) [5], Symptoms of CPM include progressive weakness leading to quadriparesis, pseudobulbar palsy and altered mental status. CPM is often fatal and is characterized neuropathologically by demyelinating lesions in the central pons. 

Over the years it has been interesting to note that many compounded products eventually become commercially available products. Recent examples might include fentanyl lozenges, minoxidil topical solution, nystatin lozenges, clindamycin topical solution, tetracaine-adrenalin-cocaine (TAG) solution, dihydroergotamine mesylate nasal spray, buprenorphine nasal spray, buffered hypertonic saline solution, and erythromycin topical solution as well as numerous other dermatological and pediatric oral liquids and some... 

Pascual JL, Khwaja KA, Chaudhury P, et al. Hypertonic saline and the micro-circulation. J Trauma 2003 54 8133. 

Rabinovici R, Rudolph A8, Vernick J, et al. A new salutary resuscitative fluid liposome encapsulated hemoglobin/hypertonic saline solution. J Trauma 1993 35 121. 

Base the repletion rate on the degree of urgency in the patient. Use of hypertonic saline (eg, 3% or 5%) will correct the deficit more rapidly. 

Hyponatraemia impaired excretion of water and enhanced sodium retention is a feature of advanced cirrhosis. Fluid restriction is often imposed, but does not reverse the problem. Administration of hypertonic saline will exacerbate fluid retention. 

Gastric lavage (with hypertonic saline solution, apomorphine injection for ingested poison). 

The mainstay of medical treatment is fluid restriction, but this may not be appropriate in the surgical and critical care patient population. Severe (<120 mmol-L-l) or symptomatic hyponatraemia (mental status changes, seizure) requires more aggressive therapy to reduce cerebral oedema. Infusion of hypertonic saline to increase plasma sodium concentrations to 120-125 mmol L-1 alleviates symptoms. Adjunct therapy with demeclocycline (600 mg-day-1) may assist management in resistant SIADH. Demeclocycline is a tetracycline antibiotic which inhibits the actions of ADH at the renal tubules. 

Nephrotoxicity has also been reviewed recently (200-202), whereas Borch and Markman (203) have published an interesting paper on the modulation of cts-Pt toxicity, by using a combination of Naddtc and hypertonic saline, for example. 

Chang L, Karin M (2001) Mammalian MAP kinase signalling cascades. Nature 410(6824) 37-40 Chen Y, Hashiguchi N, Yip L, Junger WG (2006) Hypertonic saline enhances neutrophil elastase release through activation of P2 and A receptors. Am J Physiol Cell Physiol 290(4) C1051-C1059... 

Hannon JP, Pfannkuche HJ, Fozard JR (1995) A role for mast cells in adenosine A, receptor-mediated hypotension in the rat. Br J Pharmacol 115(6) 945-952 Hashiguchi N, Lum L, Romeril E, Chen Y, Yip L, Hoyt DB, Junger WG (2007) Hypertonic saline resuscitation efficacy may require early treatment in severely injured patients. J Trauma 62(2) 299-306... 

Murao Y, Loomis W, Wolf P, Hoyt DB, lunger WG (2003) Effect of dose of hypertonic saline on its potential to prevent lung tissue damage in a mouse model of hemorrhagic shock. Shock 20(l) 29-34... 

Inoue Y, Chen Y, Pauzenberger R, Hirsh MI, Junger WG (2008a) Hypertonic saline up-regulates A3 adenosine receptor expression of activated neutrophils and increases acute lung injury after sepsis. Crit Care Med 36(9) 2569-2575... 

A 74-year-old man with rheumatoid arthritis developed nausea and headache 1.5 months after starting to take mizoribine. His serum sodium concentration fell to 118 mmol/1, but his urinary sodium excretion was normal and there was no hypotension or hemoconcentration. His serum antidiuretic hormone concentration was raised at 0.59 pg/ml in spite of a reduced serum osmolality to 254 mosm/kg. He had no organic disease likely to cause SIADH. Despite infusion of hypertonic saline, his serum sodium concentration did not return to normal. Shortly after mizoribine withdrawal, his serum sodium increased... 

Suri R, Grieve R, Normand C, et al. Effects of hypertonic saline, alternate day and daily rhDNase on healthcare use, costs and outcomes in children with cystic fibrosis. Thorax. 2002 57 841-846. 

Bullous keratopathy is a major complication of cataract surgery. In the past, penetrating keratoplasty was considered the most effective therapy for the symptomatic stage of the disease. Other surgical options have included conjunctival flaps, enucleation (reserved for blind, painful eyes) and, more recently, deep phototherapeutic keratectomy and amniotic membrane transplantation. Medical therapy of bullous keratopathy using hypertonic saline (Nad 5%) has been of marginal benefit due to its relatively weak osmotic effect. 

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