Types of Altitude Decompression Sickness:
(1) skin bends, with itching and rash, but without marbling (this may be included under Type I DCS)
(2) Type I: limb and joint pain
(3) Type II - systemic symptoms:
(3a) skin marbling or mottling (cutis marmorata)
(3b) CNS neurological symptoms ranging from minor to severe, including visual disturbances, mental confusion with impaired judgment, cerebellar signs such as vertigo and ataxia, convulsions, personality change, extreme fatigue
(3c) spinal cord involvement with anal sphincter hypotonia and absent cremasteric reflex, muscle weakness, paresthesias, numbness, flaccid paralysis
(3d) chokes, with bronchospasm, tachypnea and decreased pulmonary compliance
(3e) pains in the head, neck, torso or radicular pains (pain not limb, pain not joint)
(3f) referred pain from viscera
(3g) circulatory collapse, with loss of consciousness
Differential diagnosis:
(1) trapped gas dysbarism, with distention in the middle ear, sinuses or gastrointestinal tract
(2) gas dissecting along tissue planes, resulting in subcutaneous emphysema. mediastinal emphysema or pneumothorax
(3) angina pectoris
(4) hypoxemia
(5) motion sickness
(6) limb pain not due to DCS
(7) psychological stress
(8) spatial disorientation
(9) acceleration effects
Wirjosemito et al proposed a functional classification of Type II DCS
(1) Class 1: headache or minor neurological signs only, with flying ability intact
(2) Class 2: more severely affected than Class 1, but conscious and able to land
(3) Class 3: conscious but unable to land an aircraft safely
(4) Class 4: unconscious or unable to respond
