Beta-blocker complications

Yet another neuropsychiatric complication of TBI is a set of behavioral disturbances including impulsivity, irritability, disinhibition, and/or aggression. These symptoms appear to be more likely to arise when the brain injury involves the temporal or orbitofrontal brain regions. Treatment options for these disruptive behavioral syndromes include antidepressants, buspirone, anticonvulsants, antipsychotics, beta blockers, and stimulants (see Table 12.1). 

As with other Class I agents, patients treated with flecainide for atrial flutter have been reported with 1 1 atrioventricular conduction due to slowing the atrial rate. A paradoxical increase in the ventricular rate also may occur in patients with atrial fibrillation who receive flecainide. Concomitant negative chronotropic therapy such as digoxin or beta-blockers may lower the risk of this complication. 

Legal claims arising from glaucoma therapy may be divided into three categories adverse effects of beta-blockers, retinal detachments after initiation of miotic therapy, and complications resulting from use of CAIs. 

Interest in the possible effects of the sudden withdrawal of beta-adrenoceptor antagonists followed a 1975 report of two deaths and four life-threatening complications of coronary artery disease within 2 weeks of withdrawal of propranolol (302). Subsequent analyses did not always confirm these findings (303,304), and it has not been easy to distinguish between natural progression and deterioration caused by drug withdrawal under such circumstances. However, a case-control study in hypertensive patients showed a relative risk of 4.5 (95% Cl = 1.1, 19) associated with recent withdrawal of beta-blockers and the development of myocardial infarction or angina (305). 

Propranolol has been implicated in hypersensitivity pneumonitis (2,3), although other beta-blockers have also been associated with this complication. 

Although spironolactone has been available for more than 30 years, its efficacy and safety in patients with heart failure have only recently been recognized in the Randomized Aldosterone Evaluation Study (RALES), in which it reduced mortahty (1). Based on this and numerous smaller trials, the use of spironolactone, in conjunction with ACE inhibitors, other diuretics, and possibly beta-blockers or digoxin, represents a promising strategy for patients with severe heart failure. Its main adverse effects are hyperkalemia and antiadrenergic complications (SED-14, 675). 

Stewart WC, Garrison PM. Beta-blocker-induced complications and patients with glaucoma. Arch Intern Med 1998 158 221-226. 

B. Several studies suggest that beta blockers, such as atenolol and esmolol, given before induction reduce the anaesthetic dose requirement and may potentiate hypnosis. However, there are concerns that reducing the dose of anaesthetic may increase the risk of intra-operative awareness and it has been suggested that the use of BIS to predict the depth of anaesthesia in the presence ofbeta blockers may not be valid.There is a possibility that acute as well as chronic administration ofbeta blockers may prevent perioperative cardiac complications, but more study is needed on this. ... 

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