Although cardiac output (CO) by pulmonary artery catheterization (PAC) has been an important guideline in clinical management for more than four decades, some studies have questioned the clinical efficacy of CO in certain patient populations. Further, the use of CO by PAC has been linked to numerous complications including dysrhythmia, infection, rupture of pulmonary artery, injury to adjacent arteries, embolization, pulmonary infarction, cardiac valvular damage, pericardial effusion, and intracardiac catheter knotting. The use of PAC has been steadily declining over the past two decades. Minimally invasive and noninvasive CO monitoring have been studied in the past two decades with some evidence of efficacy. Several different devices based on pulse contour analysis are available currently, including the uncalibrated FloTrac/Vigileo system and the calibrated PiCCO and LiDCO systems. The pressure-recording analytical method (PRAM) system requires only an arterial line and is commercially available as the MostCare system. Transesophageal echocardiography (TEE) can measure CO by non-Doppler- or Doppler-based methods. The partial CO2 rebreathing technique, another method to measure CO, is marketed by Novametrix Medical Systems as the NICO system. Thoracic electrical bioimpedance (TEB) and electric bioreactance (EB) are totally noninvasive CO monitoring. Nexfin HD and the newer ClearSight systems are examples of noninvasive CO monitoring devices currently being marketed by Edwards Lifesciences. The developing focus in CO monitoring devices appears to be shifting to tissue perfusion and microcirculatory flow and aimed more at markers that indicate the effectiveness of circulatory and microcirculatory resuscitations.

Severe hemorrhage causes significant metabolic and cellular dysfunction secondary to deficient tissue perfusion and oxygen delivery. If bleeding continues, hemodynamic destabilization, hypoxemia, multiple organ failure, and death will occur. Techniques employed to promote hemostasis include surgical suture ligatures, cautery, chemical agents, self-assembling nanoparticles, and physical methods, like mechanical pressure. Improved understanding of the natural clotting cascade has allowed newly designed agents to become more targeted for clinical and military use. Topically-applied hemostatic agents have enormous clinical applications in achieving hemostasis. This manuscript describes currently available and developing topical hemostatic materials, including topical active agents, mechanical agents, synthetic/hemisynthetic hemostatic agents, and external hemostatic dressings for clinical practice.

No abstract