Physiological perspectives of therapy in bronchial hyperreactivity.

PURPOSE: This paper reviews the literature on the aetiology and therapy of bronchial hyperreactivity to describe the underlying pathophysiology, identify patients at risk and update knowledge on new and existing therapies. SOURCE: Information was obtained from monograms on New Drugs for Asthma, Respiratory Medicine: recent advances, Agents and Actions Supplements, Pulmonary Pharmacology, Anesth Analg, the European Journal of Respiration and a Medline literature search. PRINCIPAL FINDINGS: Reduced airway calibre, increased bronchial contractility, altered permeability of the bronchial mucosa, humoral and cellular mediators, and dysfunctional neural regulation are critical factors for bronchial hyperreactivity, a characteristic feature of hyperreactive airways which results in bronchoconstriction after exposure to varied stimuli. Preoperative anaesthetic considerations in these patients include FEV1 and PEFR testing to assess the severity and for optimal control of the condition. Bronchospasm causing hypoxaemia is the major intraoperative problem anticipated in these patients. Current therapeutic management of bronchoconstriction focuses on the beta 2 agonists, theophylline and steroids. Besides relaxing the airway smooth muscle these agents are all capable of altering bronchial inflammatory responses. Future developments of therapy are directed towards the inflammatory components of the disease. CONCLUSION: This review has presented background information on physiological mechanisms of smooth muscle contractility, pathophysiological alterations of bronchial contractility and the pharmacological basis of therapy in bronchoconstrictive disease. Information is presented to enable the prompt arrest and reversal of airway constriction, and to maintain prophylactic treatment during the perioperative period. Intraoperative bronchospasm is managed by adequate oxygenation and reversal of bronchoconstriction.

Pruritus ani: common infections and treatment

Pruritus ani is a manifestation of a wide spectrum of disease conditions. Infections form a minor aetiological fraction but includes organisms from the various microbiological subdiciplines. Fungal causes of pruritus ani usually come from the normal flora, and can be diagnosed in the office, by microscopy using a mixture of potassium hydroxide and dimethyl sulfoxide. Parasites causing pruritus ani may be transmitted by direct contact, the faeco-oral route or sexually. Treatment of scabies and enterobiasis should involve simultaneous treatment of family members. Articles of clothing and bed sheets must be exposed to heat. Lindane (gamma benzene hexachloride) should not be used in pregnant women and children under the age of two years to avoid potential neurotoxicity. Irrespective of the aetiology severe pruritus ani predisposes to secondary bacterial infection (AU)

Socio-biological associations of bacteriuria in pregnancy.

The prevalence and socio-biological relations of bacteriuria in Trinidadian pregnant women were investigated. The prevalence of bacteriuria was found to be 16.7% and it was more common in the 30-39 year age group, among parous women, among Negroes, and in patients with a low family income and overcrowded living conditions. Symptoms were present in 19% of bacteriuric patients and almost one-third gave a past history of urinary tract infection. Only 10% had been previously exposed to sexually transmitted diseases such as syphilis, gonorrhea and herpetic genital infections. Because of the serious consequences to mother and foetus, we advocate quantitative urine cultures for all antenatal patients, especially those coming from disadvantaged socio-economic conditions.

Considerations for implementing an antibiotic policy in hospital practice

An antibiotic policy should aim for the safe, effective and economical use of antimicrobial drugs, and to prevent their indiscriminate use and development of resistant bacterial strains. The term 'antibiotic' is used as a general term for all antimicrobial drugs. Antibiotics prescriptions should be based on clinical evidence of bacterial infection, preferably substantiated by appropriate laboratory culture and sensitivity tests. Viral infections are not an indication for antibiotic prescriptions. Patient factors to be considered for choice and dose of an antibiotic are age, pregnancy, lactation, renal and hepatic impairment. Immunodeficient patients should receive only bactericidal drugs. Severity of infection determines the route of administration. Duration of therapy should not exceed five days, unless specifically prescribed by the physician. An antibiotic should, if started as an empirical therapy not be changed before a minimum of three days trial. Prescriptions of drugs such as aztreonam, imipenem, vancomycin, piperacillin and amphotericin are to be restricted due to cost and toxicity and should be reviewed by the microbiologist(AU)