Monday, July 12, 2010

Methyl Alcohol Poisoning: Management Tips

Successful management of methyl alcohol poisoning requires prompt recognition. The most important therapeutic action is to correct the metabolic acidosis quickly. Methyl alcohol or methanol is an industrial solvent and widely used as paint thinner, paint remover, nail-polish remover and as a denaturant in ethyl alcohol. The poisoning due to methyl alcohol occurs due to consumption of rectified spirit or methylated spirit or illicit distilled ethyl alcohol. Methanol is completely absorbed within 3-4 hours of ingestion. After absorption the methanol is metabolized in the liver by the action of alcohol dehydrogenase to form formaldehyde and formic acid. Some of the ingested methanol is eliminated unchanged by the kidneys and lungs.

Ingestion of more than 30 ml of methanol/methyl alcohol is lethal, but the extent of toxicity may be influenced by concomitant ingestion of ethyl alcohol and other unknown host factors. A blood level of methanol of 20mg/dl is toxic. Severity of toxicity correlates with the level of methanol in blood. The variability in the development of methanol toxicity may be due to various liver diseases and availability and synthesis of alcohol dehydrogenase.

Symptoms of methanol poisoning after illicit alcohol consumption:

A person suspected of having consumed pure methanol or rectified spirit, industrial solvent/thinner, nail-polish remover or illicit distilled alcohol may complain of abdominal discomfort and pain, breathlessness, cardiac arrhythmia and blurred vision. If medical help is delayed the patient may go blind with delayed onset of coma.

Tips to manage methanol poisoning:

If the patient is not unconscious, try to know the type of alcoholic drink he/she has consumed. The patient should be shifted to emergency wing of a nearby hospital immediately. If the patient has consumed pure methanol, he/she should be encouraged to take around 4 oz of brandy or whisky to retard the metabolism as the enzyme alcohol dehydrogenase has more affinity for ethyl alcohol than the methyl alcohol. An assay of methanol blood levels can help to confirm the diagnosis, however, a patient having consumed a doubtful solvent and having metabolic acidosis and burred vision, should be considered a case of methanol poisoning and treated accordingly. Liver function tests along with blood pH and urine analysis should be done. The patient should be put on hemodialysis or promptly referred to a hospital where facilities for hemodialysis are available. Any arrhythmia, heart failure, convulsions or shock need urgent medical attention. If more than 4 hours have elapsed since ingestion and patient do not have arrhythmia and blurred vision, gastric lavage should be performed with sodium bicarbonate solution until the return fluid is clear of methanol. Patient should be kept under observation till considerable metabolic recovery.

Wednesday, July 7, 2010

Childhood Asthma

A wheezing child has over 80% chances of having asthma. Though wheezing has been considered as a hallmark feature of asthma but it may be associated with other disorders. Recurrent wheezing in infants and children should be considered a diagnostic feature of asthma, but all asthma does not wheeze. Pulmonary function tests (PFT) should be performed to confirm a diagnosis of asthma. Non-wheezing asthma is called 'occult asthma'. Spasmodic, persistent or recurrent cough may also be a feature of asthma. In the absence of wheezing a diagnosis of asthma may be missed in children. All cases of suspected asthma should be subjected to PFT. The response to asthma therapy can also be assessed with PFT. General pulmonary fitness in-between attacks should be monitored at home or at doctor's clinic by Peak Expiratory Flow Rate (PEFR) meter. Various precipitating and aggravating factors may differ with age in children and the trend may continue during adult life.

Because of various misconceptions, asthma is highly undertreated disorder in children. Symptoms of asthma may vary with age and asthmatic children always have different clinical patterns. Type and duration of pharmacotherapy appropriate for one pattern may be inappropriate for the other, so it is important both for the physician and the parents of children to understand these patterns.

Childhood Asthma: Pattern-I

Allergic, viral or exercise induced asthma are included in pattern-I. Here the chest congestion with wheezing and breathlessness (bronchospasm) occurs in minutes or hours and rarely lasts for more than a few days. Around 50% percent of all cases of childhood asthma have pattern-I asthma. There may be 1 to 5 episodes per year. The lung functions are near normal and these cases respond well to bronchodilators along with anti-allergic treatment and rarely need steroids.

Childhood Asthma: Pattern-II

Aetiology and features of this type also resemble pattern-I but number of attacks may be 5 to 6 per year. Longer duration of treatment with bronchodilators and sometimes steroids may be required.

Childhood Asthma: Pattern-III

Undertreated children may develop this pattern where overt symptoms of asthma may be variable with impairment of PFT. These children require steroids along with bronchodilators and the course of treatment may be longer.

Childhood Asthma: Pattern-IV

Children with this pattern experience breathlessness without considerable wheezing. Variable but persistent airway obstruction and impaired PFT have been documented in children affected by pattern-IV asthma. These patients need long term treatment with bronchodilators and steroids.

Childhood Asthma: Pattern-V

Children having no symptoms of asthma during the day but having asthmatic attack at midnight or early in the morning should be labeled as the cases of pattern-V asthma. These patients may need aerosol therapy with steroids or beta agonists at night to control the cough and wheezing. Concurrent exposure to various aggravating factors may induce severe effects. Aggravation of symptoms by exercise or a specific allergen should be recognized and reported to the treating physician.

Tuesday, July 6, 2010

Understanding Obesity

Basically the term obesity means excess of body weight due to increase in adipose tissue-mass. It is important to understand the cause of obesity for its effective management. Weight measures in excess of 'ideal body weight' with reference to normal range ideal for age, sex, height and body built. To define obesity we should measure the adiposity by measuring the skinfold thickness at triceps (normal: 23mm in males and 27mm in females) or at inter scapular region (normal: 35mm in males and 42mm in females). In most of the cases the obesity is due to overeating while in minority it could be associated with the metabolic and endocrine disorders. Beyond certain degree, obesity may increase the state of morbidity and cause associated diseases like diabetes mellitus, hypertension, coronary artery disease (CAD), gall stones, osteoarthritis etc.

Understanding patient's eating habits, likes & dislikes, temperaments, lifestyle, work schedules and adaptability to environment are important to decide a course of treatment. Compliance of doctor's advice is important for effective treatment of obesity. Dietary measurements, exercise and slimming pills are always helpful in controlling the obesity. Treatment of associated metabolic or endocrine disorders should be pursued effectively.

Dietary management:

A variety of dietary schedules ranging from zero calorie to isocaloric high protein diets are available for the treatment of obesity. Diet should be adjusted in such a way that weight loss is not in excess of one kg/week. For the success of diet regime it is important to keep a balance between 'forbidden' and 'permitted' items. Too much recommendation of low carbohydrate diet sometimes leads to a notion that non-carbohydrate diets are absolutely harmless. Rapid weight loss through zero calorie diet or fasting may sometimes be non productive as the weight lost due to loss of water would be regained quickly. The 'ad lib' items should be salads and leafy vegetables.

Exercise:

Exercise is known to increase calorie expenditure and thus leads to loss of adiposity. Exercise also increases our metabolic rate and thus supports the weight loss. In practice, however, exercise alone cannot be sufficient way to try to reduce weight. Exercise along with dietary control is good for both the general fitness and weight loss.

Anti-obesity drugs:

There are a variety of drugs for combating the food-obesity axis. There are drugs for decreasing appetite, digestion, absorption and inhibiting lipogenesis. There drugs for increasing heat production or thermogenesis. The drug treatment of obesity is not very promising, as the majority of drugs at effective therapeutic level have been found toxic.

Monday, July 5, 2010

Itching and Associated Diseases

Itching or pruritus is defined as the skin sensation that prompts the patient to scratch a particular area of the skin. Irritative stimulation of skin is caused due to activation of free nerve endings situated at the dermo-epidermal junction. Itching is a physiologic or pathologic symptom caused due to internal or external factors. Itch receptors present in the free nerve endings at the dermo-epidermal junction are stimulated by histamine and other anaphylactic substances and evoke motor response of scratching. If not controlled, scratching may lead to skin injury and infection. There is a scratching itch cycle and one feels relieved after the itching cycle. Itching or pruritus is the most common disease of the skin caused by innumerable causes. If the cause of itching/pruritus remains undiagnosed even after two weeks then it is labeled as pruritus of undetermined origin (PUO). The cause of itching/pruritus could be local or systemic. It can be associated with the following systemic diseases.

Renal disease and pruritus:

Chronic renal failure (CRF) is a well-recognized cause of generalized and persistent pruritus. Uremia during CRF and cellular changes in the skin could be the possible cause of itching/pruritus. It is not directly related to renal function parameters, as patients with acute renal failure (ARF) do not complain of itching.

Liver disease and pruritus:

Patients with liver disease may also present with mild transient or severe or persistent sensation of itching. Intra-hepatic or extra-hepatic cholestasis in these patients leads to pruritus or itching. Primary billiary cirrhosis, cholangitis, viral infections, drugs and pregnancy can cause intra-hepatic cholestasis and lead pruritus.

Pregnancy and pruritus:

Pregnant women with mild abnormalities of liver function in the form of cholestasis may develop itching in the third trimester of pregnancy. Three out of 100 pregnant women may have pruritus.

Endocrine diseases and pruritus:

Pruritus confined to genital or peri-anal areas is most common in diabetics. Patients with diabetes mellitus sometimes may present with pruritus as the main presenting feature for medical consultation. Patients suffering from hypothyroidism and hyperthyroidism may also have generalized itching or pruritus.

Pruritus in occult malignancies:

Intense itching of nostrils has been observed in patients with tumors of brain. Adenocarcinomas and squamous cell carcinomas of various organs may also lead to generalized itching/pruritus. Around 30% patients with Hodgkin's disease have been found to be affected by itching disorder; some patients may show these symptoms as presenting features.

Friday, July 2, 2010

Computer Related Health Disorders

Computer users may experience occasional discomfort in their hands, arms, shoulders, neck as well as other parts of body. If some one experiences symptoms such as recurring or persistent discomfort, pain, throbbing, aching, stiffness, burning sensation, tingling or numbness; should not ignore these warning signs. One should consult a qualified medical professional even if symptoms occur occasionally. Above cited symptoms can be associated with painful and sometimes permanently disabling injuries involving nerves, muscles or tendons. These computer associated musculoskeletal disorders (MSDs) include carpal tunnel syndrome, tendonitis, and tenosynovitis. Severity of symptoms depend on many factors like general physical & medical conditions of the computer user, daily duration of computer use, type and make of computer key board & mouse, type of monitor (CRT, TFT or LCD) and posture during computer operation. For guidelines to reduce the risk of developing an MSD, please refer to "Healthy Computing Guide". You can access the "Healthy Computing Guide" at www.microsoft.com/hardware/hcg/default.html .