In the war, both armies researched advancement in the development of battlefield recovery techniques. In the Union, a new medicinal wing was created under the jurisdiction of a “Medical Director of the Army”, the first field hospitals, small tents with a few tables or beds for the wounded, were developed, and a system of transport of the wounded to general hospitals was created, the first wooden ambulances which could hold up to around 4 wounded laying down, 1 or 2 medical officials, and a driver for the horses. The Confederacy advanced mainly by learning from Union camps they overtook, but generally had a less established medical service largely as a result of its more limited resources, vast rural areas, limited medicinal knowledge, and fewer medical professionals. The most common battle injuries were simple flesh wounds that led to amputations of limbs due to lack of better techniques for preventing the fatal spread of gangrene.
Before the Civil War, the armies tended to be small, largely because of the logistics of supply and training. Musket fire, renowned for its inaccuracy, kept casualty rates lower than they might have been. The advent of railroads, industrial production, and canned food allowed for much larger armies, and the Minié ball rifle brought about much higher casualty rates. The work of Florence Nightingale in the Crimean War brought the deplorable situation of military hospitals to the public attention, although reforms were often slow in coming.
The hygiene of the camps was poor, especially at the beginning of the war when men who had seldom been far from home were brought together for training with thousands of strangers. First came epidemics of the childhood diseases of chicken pox, mumps, whooping cough, and, especially, measles. Operations in the South meant a dangerous and new disease environment, bringing diarrhea, dysentery, typhoid fever, and malaria. There were no antibiotics, so the surgeons prescribed coffee, whiskey, and quinine. Harsh weather, bad water, inadequate shelter in winter quarters, poor policing of camps and dirty camp hospitals took their toll. This was a common scenario in wars from time immemorial, and conditions faced by the Confederate army were even worse.
When the war began, there were no plans in place to treat wounded or sick Union soldiers. After the Battle of Bull Run, the United States government took possession of several private hospitals in Washington, D.C., Alexandria, Virginia, and surrounding towns. Union commanders believed the war would be short and there would be no need create a long standing source of care for the armies medical needs. This view changed after the appointment of General George B. McClellan and the organization of the Army of the Potomac. McClellan appointed the first medical director of the army, surgeon Charles S. Tripler, on August 12, 1861. Tripler created plans to enlist regimental surgeons to travel with armies in the field, and the creation of general hospitals for the badly wounded to be taken to for recovery and further treatment. To implement the plan, orders were issued on May 25 that each regiment must recruit one surgeon and one assistant surgeon to serve before they could be deployed for duty. These men served in the initial makeshift regimental hospitals. In 1862 William A. Hammond became surgeon general and launched a series of reforms. He founded the Army Medical Museum, and had plans for a hospital and a medical school in Washington; a central laboratory for chemical and pharmaceutical preparations was created; much more extensive recording was required from the hospitals and the surgeons. Hammond raised the requirements for admission into the Army Medical Corps. The number of hospitals was greatly increased and he paid close attention to aeration. New surgeons were promoted to serving at the brigade level with the rank of Major. The Surgeon Majors were assigned staffs and were charged with overseeing a new brigade level hospital that could serve as an intermediary level between the regimental and general hospitals. Surgeon Majors were also charged with ensuring that regimental surgeons were in compliance with the orders issued by the Medical Director of the Army.
In the Union skilled, well-funded medical organizers took proactive action, especially in the much enlarged United States Army Medical Department, and the United States Sanitary Commission, a new private agency. Numerous other new agencies also targeted the medical and morale needs of soldiers, including the United States Christian Commission as well as smaller private agencies such as the Women's Central Association of Relief for Sick and Wounded in the Army (WCAR) founded in 1861 by Henry Whitney Bellows, and Dorothea Dix. Systematic funding appeals raised public consciousness, as well as millions of dollars. Many thousands of volunteers worked in the hospitals and rest homes, most famously poet Walt Whitman. Frederick Law Olmstead, a famous landscape architect, was the highly efficient executive director of the Sanitary Commission.
States could use their own tax money to support their troops as Ohio did. Following the unexpected carnage at the battle of Shiloh in April 1862, the Ohio state government sent 3 steamboats to the scene as floating hospitals with doctors, nurses and medical supplies. The state fleet expanded to eleven hospital ships. The state also set up 12 local offices in main transportation nodes to help Ohio soldiers moving back and forth.
Field hospitals were initially in the open air, with tent hospitals that could hold only six patients first being used in 1862; after many major battles the injured had to receive their care in the open. As the war progressed, nurses were enlisted, generally two per regiment. In the general hospitals one nurse was employed for about every ten patients. The first permanent general hospitals were ordered constructed during December 1861 in the major hubs of military activity in the eastern and western United States. An elaborate system of ferrying wounded and sick soldiers from the brigade hospitals to the general hospitals was set up. At first the system proved to be insufficient and many soldiers were dying in mobile hospitals at the front and could not be transported to the general hospitals for needed care. The situation became apparent to military leaders in the Peninsular Campaign in June 1862 when several thousand soldiers died for lack of medical treatment. Dr. Jonathan Letterman was appointed to succeed Tripler as the second Medical Director of the Army in 1862 and completed the process of putting together a new ambulance corps. Each regiment was assigned two wagons, one carrying medical supplies, and a second to serve as a transport for wounded soldiers. The ambulance corps was placed under the command of Surgeon Majors of the various brigades. In August 1863 the number of transport wagons was increased to three per regiment.
Union medical care improved dramatically during 1862. By the end of the year each regiment was being regularly supplied with a standard set of medical supplies included medical books, supplies of medicine, small hospital furniture like bed-pans, containers for mixing medicines, spoons, vials, bedding, lanterns, and numerous other implements. A new layer of medical treatment was added in January 1863. A division level hospital was established under the command of a Surgeon-in-Chief. The new divisional hospitals took over the role of the brigade hospitals as a rendezvous point for transports to the general hospitals. The wagons transported the wounded to nearby railroad depots where they could be quickly transported to the general hospitals at the military supply hubs. The divisional hospitals were given large staffs, nurses, cooks, several doctors, and large tents to accommodate up to one hundred soldiers each. The new division hospitals began keeping detailed medical records of patients. The divisional hospitals were established at a safe distance from battlefields where patients could be safely helped after transport from the regimental or brigade hospitals.
Although the divisional hospitals were placed in safe locations, because of their size they could not be quickly packed in the event of a retreat. Several divisional hospitals were lost to Confederates during the war, but in almost all occasions their patients and doctors were immediately paroled if they would swear to no longer bear arms in the conflict. On a few occasions, the hospitals and patients were held several days and exchanged for Confederate prisoners of war.
The U.S. Army learned many lessons and in 1886, it established the Hospital Corps. The Sanitary Commission collected enormous amounts of statistical data, and opened up the problems of storing information for fast access and mechanically searching for data patterns.
The Confederacy was quicker to authorize the establishment of a medical corps than the Union, but the Confederate medical corp was at a considerable disadvantage throughout the war primarily due to the lesser resources of the Confederate government. A Medical Department was created with the initial army structure by the provisional Confederate government on February 26, 1861. President Jefferson Davis appointed David C. DeLeon Surgeon General. Although a leadership for a medical corp was created, an error by the copyist in the creation of the military regulations of the Confederacy omitted the section for medical officers, and none were mustered into their initial regiments. Many physicians enlisted in the army as privates, and when the error was discovered in April, many of the physicians were pressed into serving as regimental surgeons.
DeLeon had little experience with military medicine, and he and his staff of twenty-five began creating plans to implement army-wide medical standards. The Confederate government appropriated money to purchase hospitals to serve the army, and the development of field services began after the First Battle of Manassas. The early hospitals were quickly overrun by wounded, and hundreds had to be sent by train to other southern cities for care following the battle. As a result of the poor planning, Davis demoted DeLeon and replaced him with Samuel Preston Moore. Moore had more experience than DeLeon and quickly moved to speed the implementation of medical standards. Because many of the surgeons in the regiments had been pressed into service, some were not qualified to be surgeons. Moore began reviewing the surgeons and replacing those found to be inadequate for their duties.
Initially the Confederacy employed a policy of furloughing wounded soldiers to return home for recovery. This was a result of their lack of field hospitals and limited capacity in their general hospitals. In August 1861, the army began the construction of new larger hospitals in several southern cities and the furloughing policy was gradually halted. The earliest recruits for surgeons were required to bring their own supplies, a practice that was ended during 1862. The government began providing each regiment with a pack with medical supplies including medicines and surgical instruments. The Confederacy, however, had limited access to medicinal supplies and relied on their blockade-running ships to import needed medicines from Europe, supplies captured from the North or traded with the North through Memphis. Anesthetics were not in as short supply as medical instruments, something highly prized. Field hospitals were set up at the regimental level and located in an open area behind the lines of battle and staffed by two surgeons, one being senior. It was the responsibility of the regimental surgeons to determine which soldiers could return to duty and which should be sent to the general hospitals. There were no intermediary hospitals, and each regiment was responsible for transporting its wounded to the nearest rail depot, where the injured were transported to the general hospitals for longer term care. In some of the lengthier battles, buildings were seized to serve as a temporary secondary hospital at a divisional level where the severely wounded could be held. The secondary facilities were staffed by the regimental surgeons, who pooled their resources to care for the wounded and were oversaw by a divisional surgeon.
The most common battlefield injury was being wounded by enemy fire. Unless the wounds were minor, this often led to amputation of limbs to prevent infection from setting in; anti-biotics had not yet been discovered. Amputations had to be made at the point where the wound occurred, often leaving men with stub limbs. Skin was taken from the amputated limb to cover the wound and stitched to the stump. Men were generally partially sedated with chloroform or alcohol before surgeries. When properly done, the patient would feel no pain during their surgery, but would not be totally unconscious. Stonewall Jackson, for example, recalled the sound of the saw cutting through the bone of his arm, but recalled no pain. Infection was the most common cause of death of injured soldiers.
It has been said that the American Civil War was the first "modern war" in terms of technology and lethality of weapons, but that it was simultaneously fought "at the end of the medical Middle Ages." Very little was known about the causes of disease, and so a minor wound could easily become infected and take a life. Battlefield surgeons were under qualified and hospitals were generally poorly supplied and staffed. The most common battlefield operation was amputation. If a soldier was badly wounded in the arm or leg, amputation was usually the only solution. Surprisingly, about 75% of amputees survived the operation. Contrary to popular belief, few soldiers experienced amputation without any anesthetic. Heavy doses of chloroform were administered; in fact, a few soldiers died of chloroform poisoning, rather than their wounds.
If a wound produced pus, it was thought that it meant the wound was healing, when in fact it meant the injury was infected. Roughly three in five Union casualties and two in three Confederate casualties died of disease.
North and South, over 20,000 women volunteered to work in hospitals, usually in nursing care. They assisted surgeons during procedures, gave medicines, supervised the feedings and cleaned the bedding and clothes. They gave good cheer, wrote letters the men dictated, and comforted the dying.
The Union Army nurse superintendent was Dorothea Lynde Dix, while Clara Barton, Mary Livermore, Mary Ann Bickerdyke, and Annie Wittenmeyer played leadership roles.
Based on their experiences in the war, many veterans went on to develop high standards for medical care and new medicines. The modern pharmaceutical industry began developing in the decades after the war. Colonel Eli Lilly had been a pharmacist; he built a pharmaceutical empire after the war. Clara Barton founded the American Red Cross to provide civilian nursing services in wartime.