Abstract:
Hyperbaric oxygen (HBO) therapy still lacks proper interpretations of its many actions. This hypothesis is based on reports of temporarily elevated peripheral vascular resistance (PVR) during HBO sessions. Besides that, during HBO sessions, hyperoxygenated tissues can reduce their perfusion so much that CO2 can accumulate in them. Tissue perfusion depends on vascular innervation and on the balance between systemic constrictors and local dilators. During an HBO session, increased tissue oxygen levels suppress dilatory mechanisms. Tissue hyperoxygenation increases PVR, suggesting that the HBO action on an edematous tissue may be caused by an oxygen-induced disbalance among Starling capillary forces. The presented hypothesis is that oxygen-caused arteriolar constriction reduces the hydrostatic pressure in downstream capillaries. Thus, more tissue fluid is absorbed in vascular capillaries, under the condition that the plasma colloid osmotic pressure remains unaltered during the HBO session. Among several known mechanisms behind the HBO actions, the vasoconstriction has been listed as a therapeutic modality for the reduction of the tissue edema, for a crush injury, for burns (in an acute phase), and for the compartment syndrome. The Bell\'s palsy is among often listed indications for the HBO treatment, although evidence is poor and reports of randomized trials are scarce.
摘要:
高压氧(HBO)治疗仍然缺乏对其许多行为的正确解释。该假设基于HBO会话期间外周血管阻力(PVR)暂时升高的报道。除此之外,在HBO会议期间,高氧合的组织可以减少它们的灌注,以至于二氧化碳可以在其中积聚。组织灌注取决于血管神经支配以及全身收缩器和局部扩张器之间的平衡。在HBO会议期间,增加的组织氧水平抑制扩张机制。组织过度氧合增加PVR,表明HBO对水肿组织的作用可能是由氧引起的Starling毛细血管力失衡引起的。提出的假设是,氧气引起的小动脉收缩会降低下游毛细血管的静水压力。因此,更多的组织液被血管毛细血管吸收,在HBO期间血浆胶体渗透压保持不变的条件下。在HBO行动背后的几种已知机制中,血管收缩已被列为减少组织水肿的治疗方式,因为挤压伤,烧伤(在急性期),和隔室综合症。贝尔麻痹是HBO治疗经常列出的适应症之一,尽管证据不足,但随机试验的报告很少.