text: Chapter 1
  * Weather conditions.
  Medical Logistics
  1-163. FM 3-90 does not discuss medical logistics. (See FM 4-02 and ATP 4-02.1 for more information on
  medical logistics.)
  Additional Medical Considerations
  1-164. Tactical combat casualty care and casualty evacuation are not medical support functions. However,
  these are vital concepts for leaders to understand and implement during tactical operations.
  Tactical Combat Casualty Care
  1-165. Tactical combat casualty care is divided into the three phases: care under fire, tactical field care, and
  tactical evacuation care. Tactical combat casualty care occurs during a combat mission and is the military
  counterpart to prehospital emergency medical treatment. Tactical combat casualty care in the military is most
  commonly provided by enlisted personnel and includes self-aid and buddy aid (first aid), combat lifesaver
  (enhanced first aid), Army combat medics and critical care flight paramedics, corpsmen from the Navy and
  Marine Corps and the U.S. Coast Guard, and both medics and pararescuemen in the U.S. Air Force.
  1-166. In the care under fire phase, combat medical personnel and their units are under effective hostile fire
  and are very limited in the care they can provide. During this phase, only those lifesaving interventions that
  must be performed immediately are undertaken. Soldiers mainly focus on stabilizing the casualties to
  transport them to the next higher medical facility.
  1-167. During the tactical field care phase, medical personnel and their patients are no longer under
  effective hostile fire and medical personnel can provide more extensive patient care. In this phase,
  interventions directed at other life-threatening conditions, as well as resuscitation and other measures to
  increase the comfort of the patient may be performed. During tactical field care, personnel must be prepared
  to transition back to care under fire, or to prepare the casualty for tactical evacuation, as the tactical situation
  changes.
  1-168. In the tactical evacuation care phase, casualties are transported from the battlefield to medical
  treatment facilities. Evacuation can be by either MEDEVAC or casualty evacuation. (See FM 4-02 for more
  information on tactical combat casualty care).
  Casualty Evacuation
  1-169. If MEDEVAC platforms are available, casualties should be evacuated on these platforms to ensure
  that they receive proper enroute medical care. However, if dedicated medical evacuation assets are
  unavailable, units use non-dedicated vehicles to transport causalities. Casualty evacuation is the movement
  of casualties aboard nonmedical vehicles or aircraft without enroute medical care (FM 4-02). Casualty
  evacuation (CASEVAC) involves the unregulated movement of casualties using tactical or logistic aircraft
  and vehicles. These vehicles or aircraft are not staffed with medical personnel for enroute care (unless
  augmentation is planned for in the operation plan). These vehicles and aircraft do not have organic medical
  equipment. If the combat medic is not available to provide care enroute, the combat lifesaver may accompany
  the casualties to monitor their conditions.
  1-170. Combat operations place a significant burden on medical resources due to the magnitude and
  lethality of the forces involved. Medical units must anticipate large numbers of casualties in a short period
  due to the capabilities of modern conventional weapons and the possible employment of weapons of mass
  destruction. These mass casualty situations can rapidly exceed the capabilities of medical assets. Mass
  casualty refers to any number of human casualties produced across a period of time that exceeds available
  medical support capabilities (JP 4-02). Careful planning and coordination are necessary to minimize the
  extent to which medical capabilities are overwhelmed. CASEVAC must occur concurrently with operations.
  Units that cease aggressive maneuver to evacuate casualties while in enemy contact are likely to both suffer
  additional casualties while stationary and fail their mission. Effective management of mass casualty situations