The clinical manifestations of shock depend on the precipitating insult. In hypovolemic and cardiogenic shock, patients exhibit hypotension, a weak rapid pulse, tachypnea, and cool, clammy, cyanotic skin. As already noted, in septic shock, the skin may be warm and flushed owing to peripheral vasodilation. The primary threat to life is the underlying initiating event (e.g., myocardial infarction, severe hemorrhage, bacterial infection). However, the cardiac, cerebral, and pulmonary changes rapidly aggravate the situation. If patients survive the initial period, worsening renal function can provoke a phase dominated by progressive oliguria, acidosis, and electrolyte imbalances.
Prognosis varies with the origin of shock and its duration. Thus, more than 90% of young, otherwise healthy patients with hypovolemic shock survive with appropriate management; by comparison, septic or cardiogenic shock is associated with substantially worse outcomes, even with state-of-the-art care.
•Shockisdefinedasastateofsystemictissuehypoperfusionresultingfromreducedcardiacoutputand/orreducedeffectivecirculatingbloodvolume.
Themajortypesofshockarecardiogenic(e.g.,myocardialinfarction),hypovolemic(e.g.,bloodloss),andseptic(e.g.,infections).
Shockofanyformcanleadtohypoxictissueinjuryifnotcorrected.
Septicshockiscausedbythehostresponsetobacterialorfungalinfections;itischaracterizedbyendothelialcellactivation,vasodilation,edema,disseminatedintravascularcoagulation,andmetabolicderangements.
Akhtar S: Fat embolism, Anesthesiol Clin 27:533, 2009. [Recent overview of the pathogenesis and clinical issues in fat embolism syndrome.]
Alberelli MA, De Candia E: Functional role of protease activated receptors in vascular biology, Vascul Pharmacol 62:72–81, 2014. [An exhaustive review of the role played by PARs in hemostasis.]
Angus DC, van der Poll T: Severe sepsis and septic shock, N Engl J Med 840:2013. [An excellent review of clinical features, pathogenesis, and outcome of septic shock.]
Benson MD: Current concepts of immunology and diagnosis in amniotic fluid embolism, Clin Dev Immunol doi:10.1155/2012/946576: 2012. [Discussion of the pathophysiology of amniotic fluid embolism.]
Cawcutt KA, Peters SG: Severe sepsis and septic shock: clinical overview and update on management, Mayo Clin Proc 89:1572, 2014. [A brief clinical review of sepsis.]
Chapman JC, Hajjar KA: Fibrinolysis and the control of blood coagulation, Blood Rev 29:17, 2015. [An updated discussion of fibrinolysis and its role in the regulation of coagulation.]
Chaturvedi S, McCrae KR: Recent advances in the antiphospholipid antibody syndrome, Curr Opin Hematol 21:371, 2014. [A discussion of the pathophysiology of this important and complex entity.]
Coleman DM, Obi A, Henke PK: Update in venous thromboembolism: pathophysiology, diagnosis, and treatment for surgical patients, Curr Probl Surg 52:233, 2015. [An exhaustive review of this common clinical condition.]