The Cardiovascular System and its Disorders
Walter F. Stanaszek, Mary J. Stanaszek, Robert J. Holt, Steven Strauss in Understanding Medical Terms, 2020
Hypovolemic shock is caused by a reduced blood volume, which may be hemorrhagic (caused by bleeding, whether external as in traumatic injury or internal such as from a perforated ulcer or a ruptured aneurysm) or nonhemorrhagic. Diarrhea, vomiting, unreplaced excess perspiration, or diabetes mellitus can cause severe dehydration, which can reduce blood volume sufficiently to result in nonhemorrhagic hypovolemic shock. Similarly, severe burns result in volume depletion, and ascites or any other conditions that sequester large volumes of fluid outside the vasculature will cause hypovolemia in the vessels and reduce tissue perfusion.
Clinical Approach to Case of PPH
Gowri Dorairajan in Management of Normal and High Risk Labour During Childbirth, 2022
The goal of resuscitation is to prevent morbidity and mortality. It is prudent to call for help. One should call the senior most of the team on-site and the consultant, if needed, early in the management. One should alert the nursing and other staff, the blood bank, and the anaesthetist. The classification of hypovolemic shock as laid down by the advanced trauma [1] life support should guide in recognizing the severity. There is a 40%–50% increase in plasma volume throughout pregnancy. One must remember that the pulse and blood pressure may show a change only when immense blood loss has happened. So, one should be alert about the visual quantification of blood loss and act accordingly. Shock index (Pulse rate/systolic blood pressure) is helpful to assess the volume loss clinically. The shock index should always be less than 1.
Lens Models of Human Judgment for Rater-Mediated Assessments
George Engelhard, Stefanie A. Wind in Invariant Measurement with Raters and Rating Scales, 2017
In order to explore this judgmental process, a group of nurses was presented with a series of simulated medical scenarios in which clinical information related to six symptoms was presented based on advice from expert clinicians. Each scenario included variations on the level of normality of each symptom among patients who are not experiencing hypovolemic shock: normal, equivocal, and abnormal. For each scenario, the nurses were asked to estimate the likelihood that the simulated patient was in shock (0–100 scale), and provide a dichotomous judgment regarding the patient’s status as not in shock (0) or in shock (1). The nurses completed the judgmental procedure prior to and immediately following the presentation of a lecture related to clinical diagnosis. Using these judgments, analyses focused on examining nurses’ judgmental accuracy, along with differences in the weights assigned to clinical information across individual and groups of nurses.
Modified ‘sandwich’ injection with or without ligation for variceal bleeding in patients with both esophageal and gastric varices: a retrospective cohort study
Published in Scandinavian Journal of Gastroenterology, 2020
Tingting Hu, Simon Stock, Wandong Hong, Yongping Chen
Failure to control bleeding was based on Baveno V consensus. It required that the time frame for the acute bleeding episode should be 120 h (5 days) and defined failure as death or the need to change therapy according to one of the following criteria: (1) Fresh hematemesis or nasogastric aspiration of ≥100 mL of fresh blood ≥2 h after the start of a specific drug treatment or therapeutic endoscopy. (2) Development of hypovolemic shock. (3) A 3 g drop in Hb (equivalent to a 9% drop in hematocrit) within any 24 h period if no blood transfusion is administered [19]. Rebleeding was defined as occurrence of one or more times clinically significant rebleeding (example: melena or/and hematemesis) from portal hypertensive sources after day 5 [20]. As proposed by Baveno VI consensus, 6 weeks should be the primary endpoint for studies for treatment of acute variceal bleeding. Therefore, we analyzed 6-week rebleeding rate [4]. The 1-year rebleeding rate was defined as cumulative rebleeding rate within 1-year after day 5.
Echocardiography in a critical care unit: a contemporary review
Published in Expert Review of Cardiovascular Therapy, 2022
Muhammad Mohsin, Muhammad Umar Farooq, Waheed Akhtar, Waqar Mustafa, Tanzeel Ur Rehman, Jahanzeb Malik, Taimoor Zahid
Hypovolemic shock is the presence of inadequate organ perfusion caused by intravascular volume loss in acute settings [2,53]. This causes a drop in preload and cardiac output and reduces micro- and macrocirculation, leading to negative tissue metabolism and an inflammatory reaction [2,54]. Assessment of intravascular volume, although pertinent in all types of circulatory shock, is particularly used as a starting point in hypovolemic shock [55]. In contemporary practice, a clinician can assess volume status on 2D and M-mode echocardiography. LV collapse at the end of systole implies severe hypovolemia and a fixed bowing of atrial septum toward the right chambers means adequate fluid resuscitation was given [56]. However, these signs are not specific to intravascular fluid status.
Dengue: current state one year before WHO 2010–2020 goals
Published in Acta Clinica Belgica, 2022
K Wellekens, A Betrains, P De Munter, W Peetermans
At the time of defervescence on day 4–5 (range 3–7 days), a minority of patients will develop a vascular leak syndrome due to increased vascular permeability, making them pass to the critical phase [3]. Hemoconcentration, hypoproteinemia, ascites and pleural effusions are suggestive findings [3,10–12]. Hypovolemic shock arises if intrinsic compensatory mechanisms fail to maintain adequate circulation and the pulse pressure drops eventually below 20 mmHg [3]. This gives rise to organ hypoperfusion, metabolic acidosis, organ failure, and disseminated intravascular coagulation with associated hemorrhage. A flushed face and warm trunk with cold and clammy extremities, irritability, abdominal pain, and reduced urine output may be observed. The hemorrhagic manifestations are usually minor, but some patients have profound skin (petechiae, ecchymoses, bleeding at venipuncture sites) or mucosal (nasal or gingival bleeding, melaena, hematemesis, and menorrhagia) bleeding [3,10–12]. According to the definition of ‘severe dengue’ (Figure 1), organ impairment such as hepatitis/acute liver failure, encephalitis, myocarditis and severe bleeding may also develop in the absence of profound plasma leakage or shock [3,17].
Related Knowledge Centers
- Bleeding
- Dehydration
- Extracellular Fluid
- Tachycardia
- Volume Contraction
- Hypovolemia
- Ischemia
- Multiple Organ Dysfunction Syndrome
- Shock
- Medical Emergency