Magnesium Shown More Effective than Standard Drug Therapy
| Magnesium Shown More Effective than Standard Drug Therapy |
In the following studies, intravenous
magnesium sulfate has been found to relieve respiratory failure in asthmatic patients not
responsive to standard drug therapy.
EM Skobeloff, et al., of the Medical College of Pennsylvania, Department of Emergency Medicine, Philadelphia, reported in JAMA their study of thirty-eight patients suffering from acute exacerbations of moderate to severe asthma who were treated in an emergency department with an intravenous infusion of saline placebo or 1.2 g of magnesium sulfate after conventional beta- agonist therapy failed to produce significant improvement in peak expiratory flow rate.
Nineteen patients were randomized into each of two groups in a placebo-controlled, double-blind clinical trial involving magnesium sulfate. The treatment group demonstrated an increase in peak expiratory flow rate from 225 to 297 L/min (32% increase) as compared with 208 to 216 L/min (4% increase) seen in the placebo group.
In addition, the number admitted vs
discharged was significantly better for the treatment group (7 vs 12) than the placebo
group (15 vs 4). They concluded that intravenous magnesium sulfate may represent a
beneficial adjunct therapy in patients with moderate to severe asthma who show little
improvement with beta-agonists.89
In a subsequent study by Skobeloff and colleagues, further evidence of the efficacy of magnesium was reported.
A four-months'-pregnant woman without a prior history of asthma presented to the emergency department with acute bronchitis compounded by bronchospasm.
The patient failed to respond adequately to aggressive treatment with conventional therapy.
Prior to hospital admission, a bolus of 3 g IV magnesium sulfate was infused with complete abatement of her bronchospasm, significantly increasing peak expiratory flow rate without any significant side effects.
The patient was discharged home and remained asymptomatic thereafter.90
The first reported case of the use of magnesium to prevent intubation and assisted ventilation in a patient with acute respiratory failure complicating asthma, was made by RM McNamara, et al..
IV magnesium sulfate was administered to a 72-year-old man with acute respiratory failure secondary to a severe asthma attack.
The patient had clinically deteriorated despite aggressive standard treatment and evidenced acidosis and hypercarbia by arterial blood gas determination.
An IV dose of 1 g MgSO4 produced
rapid clinical and arterial blood gas improvement and enabled management of the patient
without endotracheal intubation and mechanical ventilation.91
The second such case was reported by LM Kuitert and SL Kletchko in 1991.
In their report, they noted that magnesium, a physiologic calcium antagonist, is known to have a direct effect on calcium uptake in smooth muscle, resulting in smooth muscle relaxation.
Studies of magnesium sulfate infusions in patients with mild or moderate-to-severe acute asthma have shown that it may have a significant bronchodilatory effect, similar to that of salbutamol (albuterol).
They presented a case of a patient
with acute severe life- threatening asthma (initially in cardiorespiratory arrest) who
responded to an IV infusion of magnesium sulfate after aggressive pharmacologic management
failed to result in clinical improvement.92
Infusion of MgSO4 caused a significant improvement in FEV1 (0.94 +/- 0.39L to 1.3 +/- 0.44 L) and an improvement in clinical signs and symptoms in ten out of 12 administrations.
They concluded that these findings
confirm intravenous MgSO4 may be used as an adjunct to classic beta 2-agonist therapy in
cases of severe acute asthma; its exact place in the treatment of asthma remains to be
determined in large-scale studies.93