Medical Matters Muiris HoustonMedicine and armed conflict may, at first glance, seem unlikely bedfellows. But where there is war, there are casualties, many of whom have multiple severe wounds requiring medical treatment.
From the mobile army surgical hospital (MASH) in Korea to the makeshift modern structures used in Afghanistan and Iraq, armies have been backed by combat hospitals and medical corps personnel.
Landmines, suicide bombers and roadside bombs cause severe trauma to the head and the extremities. Penetrating wounds from bullets and shrapnel lead to a type of injury rarely seen in a civilian environment.
Military medicine is a sought-after training ground. During the North's troubles, general and orthopaedic surgeons-in-training looked for positions in Northern Ireland's hospitals.
Sadly, they were guaranteed quality training in the treatment of multiple bullet wounds, blast trauma and knee-capping injuries.
With the troubles over, British military surgeons now spend 12 weeks at trauma centres and intensive care units in South African hospitals.
There were almost 20,000 murders in South Africa in 2004, so a surgeon in a Johannesburg hospital is likely to treat up to six gunshot wounds in a 30-hour shift. Such training helps to ease the learning curve when the military doctors are posted to Iraq and Afghanistan.
During the second World War, the luxury of pre-conflict training simply did not exist. So for doctors such as Aidan MacCarthy, author of A Doctor's War, it was a case of improvising on the job.
MacCarthy, a native of Berehaven in west Cork, graduated from Cork Medical School in 1938. Medical appointments in the Republic were hard to come by, so the newly qualified doctor went to England looking for work. Soon tiring of locum work in general practice, he joined the RAF Medical Branch and was initially posted to France.
It is MacCarthy's experience of life in Japanese prisoner of war camps that make the book an especially riveting read.
Despite a lack of medical equipment and drugs, MacCarthy and his colleagues improvised. Here he describes the treatment of lung abscesses: "First I cut into the lung over the site of the abscess with a razor blade, taking care not to puncture the lung. Then I planted a drainage needle, which was inserted through a hollow tube [ tracula], both homemade in the factory. These had been sterilised by immersion in potassium permanganate solution . . . Using a homemade syringe the pus was sucked out.
"The protruding tube was left to bubble through water in a bottle. Every three days I removed the equipment, sterilised it and reinserted the tube. Three weeks later my efforts were rewarded, as both abscesses dried up. The incision was allowed to heal and both patients survived their captivity."
Many prisoners were chronically ill. Beri-beri, due to a deficiency of vitamin B in their diet, was a common problem. Thiamine (vitamin B12) is an essential co-factor in many of the body's enzyme reactions.
Stores of thiamine are small and so signs of deficiency quickly develop with an inadequate intake. There are two main types of beri-beri; dry beri-beri causes stiffness and cramps in the legs, followed by weakness and pins and needles. A burning sensation in the feet and scrotum are also characteristic symptoms, which are the result of damage to peripheral nerves.
Wet beri-beri causes swelling of the abdomen, scrotum and ankles. The heart muscle is also damaged, leading to cardiac failure and breathlessness.
According to MacCarthy, prisoners were also prone to retrobulbar neuritis - an inflammation of the ends of the optic nerve. This resulted in a gradual loss of vision. Untreated, the visual loss proceeded to permanent blindness.
When the army doctors found that a mixed fat and protein diet brought about some improvement, they improvised and took a calculated risk: the patients were given an intravenous injection of a small amount of typhoid vaccine.
The author explains: "This was normally given as a skin injection for protection against typhoid and paratyphoid. Given intravenously, it produced an artificial fever [ 102-103 degrees] within 30 minutes. This lasted about an hour. Our theory was that the fever would increase metabolic rate [ ie it would accelerate the breakdown and absorption of fats and proteins in the body].
"In the majority of cases it worked, and with continued treatment the vision returned to normal or near normal. A small percentage, however, were too far gone and became totally blind."
On the basis of urgent needs, military medicine has often been at the cutting edge of surgical development.
It is likely that techniques learned while treating front-line troops in Iraq and Afghanistan will become part of routine medical practice in the years ahead.
A Doctor's War by Aidan MacCarthy is published by The Collins Press, €12.95.
Dr Houston is pleased to hear from readers at mhouston@irish-times.ie but regrets he is unable to reply to individual medical queries.