The history and evolution of circulatory shock

Ischemic Pancreatitis Is an Important Cause of Acute Pancreatitis in the Intensive Care Unit

BACKGROUND

Ischemic pancreatitis (IP) has mainly been described in case reports. The aims of the study were to assess the frequency, clinical characteristics and outcomes in patients with IP among patients hospitalized in the intensive care unit (ICU) for acute pancreatitis (AP).

METHODS

All patients with first time AP between 2011 and 2018 in the ICU of Landspitali Hospital, Iceland were retrospectively included. IP as an etiology required a clinical setting of circulatory shock, arterial hypotension, hypovolemia and/or arterial hypoxemia [PaO 2 of 60 mm Hg (8.0 kPa), or less] before the diagnosis of AP without prior history of abdominal pain to this episode. Other causes of AP were ruled out. IP patients were compared with patients with AP of other etiologies, also hospitalized in the ICU.

RESULTS

Overall 67 patients with AP were identified (median age 60 y, 37% females), 31% idiopathic, 24% alcoholic, 22% IP, 15% biliary, and 8% other causes. Overall, 15 (22%) fulfilled the predetermined criteria for IP, 9 males (64%), median age 62 years (interquartile range: 46 to 65). IP was preceded mainly by systemic shock (73%). Other causes included dehydration, hypoxia, or vessel occlusion to the pancreas. Necrosis of the pancreas was rare with one patient requiring pancreatic necrosectomy. Inpatient mortality was higher among patients with IP than in other patients with AP (33% vs. 14%, P =0.12).

CONCLUSIONS

IP was found in a significant proportion of AP patients hospitalized in the ICU. The main causes of IP were systemic shock and hypoxia. IP was associated with ∼30% mortality.

What We Owe the World Wars: Challenges That Fueled Surgical Innovation

War has the unique ability to intensify obstacles that surgeons face daily in civilian hospitals. After a brief overview of the historical context of the first and second world wars, this article will focus on how those daily challenges, namely limited skill, bleeding, and infection, led to an era of surgical innovation and standardization of surgical education.

Fluid resuscitation in human sepsis: Time to rewrite history?

Fluid resuscitation continues to be recommended as the first-line resuscitative therapy for all patients with severe sepsis and septic shock. The current acceptance of the therapy is based in part on long history and familiarity with its use in the resuscitation of other forms of shock, as well as on an incomplete and incorrect understanding of the pathophysiology of sepsis. Recently, the safety of intravenous fluids in patients with sepsis has been called into question with both prospective and observational data suggesting improved outcomes with less fluid or no fluid. The current evidence for the continued use of fluid resuscitation for sepsis remains contentious with no prospective evidence demonstrating benefit to fluid resuscitation as a therapy in isolation. This article reviews the historical and physiological rationale for the introduction of fluid resuscitation as treatment for sepsis and highlights a number of significant concerns based on current experimental and clinical evidence. The research agenda should focus on the development of hyperdynamic animal sepsis models which more closely mimic human sepsis and on experimental and clinical studies designed to evaluate minimal or no fluid strategies in the resuscitation phase of sepsis.

Septic Shock: Advances in Diagnosis and Treatment

IMPORTANCE

Septic shock is a clinical emergency that occurs in more than 230,000 US patients each year. OBSERVATIONS AND ADVANCES: In the setting of suspected or documented infection, septic shock is typically defined in a clinical setting by low systolic (≤90 mm Hg) or mean arterial blood pressure (≤65 mm Hg) accompanied by signs of hypoperfusion (eg, oliguria, hyperlactemia, poor peripheral perfusion, or altered mental status). Focused ultrasonography is recommended for the prompt recognition of complicating physiology (eg, hypovolemia or cardiogenic shock), while invasive hemodynamic monitoring is recommended only for select patients. In septic shock, 3 randomized clinical trials demonstrate that protocolized care offers little advantage compared with management without a protocol. Hydroxyethyl starch is no longer recommended, and debate continues about the role of various crystalloid solutions and albumin.

CONCLUSIONS AND RELEVANCE

The prompt diagnosis of septic shock begins with obtainment of medical history and performance of a physical examination for signs and symptoms of infection and may require focused ultrasonography to recognize more complex physiologic manifestations of shock. Clinicians should understand the importance of prompt administration of intravenous fluids and vasoactive medications aimed at restoring adequate circulation, and the limitations of protocol-based therapy, as guided by recent evidence.

Validating a pragmatic definition of shock in adult patients presenting to the ED

OBJECTIVE

The importance of the early recognition of shock in patients presenting to emergency departments is well recognized, but at present, there is no agreed practical definition for undifferentiated shock. The main aim of this study was to validate an a priori clinical definition of shock against 28-day mortality.

DESIGN, SETTING AND SUBJECTS

This prospective, observational, cross-sectional, single-center study was conducted in Hong Kong, China. Data were collected between July 1, 2012, and January 31, 2013. An a priori definition of shock was designed, whereby patients admitted to the resuscitation room or high dependency area of the emergency department were divided into 1 of 3 groups-no shock, possible shock, and shock. The primary outcome was 28-day mortality. Secondary outcomes were in-hospital mortality or admission to the intensive or coronary care unit.

MEASUREMENTS AND MAIN RESULTS

A total of 111 patients (mean age, 67.2 ± 17.1 years; male = 69 [62%]) were recruited, of which 22 were classified as no shock, 54 as possible shock, and 35 as shock. Systolic blood pressure, mean arterial pressure, lactate, and base deficit correlated well with shock classifications (P < .05). Patients who had 3 or more positively defined shock variables had a 100% poor composite outcome rate (5 of 5). Patients with 2 shock variables had a 66.7% (4 of 6) poor composite outcome rate.

CONCLUSIONS

A simple, practical definition of undifferentiated shock has been proposed and validated in a group of patients presenting to an emergency department in Hong Kong. This definition needs further validation in a larger population and other settings.

Estimation of cardiac output and systemic vascular resistance using a multivariate regression model with features selected from the finger photoplethysmogram and routine cardiovascular measurements

Background

Cardiac output (CO) and systemic vascular resistance (SVR) are two important parameters of the cardiovascular system. The ability to measure these parameters continuously and noninvasively may assist in diagnosing and monitoring patients with suspected cardiovascular diseases, or other critical illnesses. In this study, a method is proposed to estimate both the CO and SVR of a heterogeneous cohort of intensive care unit patients (N=48).

Methods

Spectral and morphological features were extracted from the finger photoplethysmogram, and added to heart rate and mean arterial pressure as input features to a multivariate regression model to estimate CO and SVR. A stepwise feature search algorithm was employed to select statistically significant features. Leave-one-out cross validation was used to assess the generalized model performance. The degree of agreement between the estimation method and the gold standard was assessed using Bland-Altman analysis.

Results

The Bland-Altman bias ±precision (1.96 times standard deviation) for CO was -0.01 ±2.70 L min^-1 when only photoplethysmogram (PPG) features were used, and for SVR was -0.87 ±412 dyn.s.cm^-5 when only one PPG variability feature was used.

Conclusions

These promising results indicate the feasibility of using the method described as a non-invasive preliminary diagnostic tool in supervised or unsupervised clinical settings.

Hypoxic hepatitis in critically ill patients: incidence, etiology and risk factors for mortality

PURPOSE

Hypoxic hepatitis may be induced by hemodynamic instability or arterial hypoxemia in critically ill patients. We investigated the incidence, etiology, association with systemic ischemic injury and risk factors for mortality in this population.

METHODS

Retrospective analysis of patients with hypoxic hepatitis admitted to a multidisciplinary intensive care unit (ICU) of a university hospital. Hypoxic hepatitis was defined as the existence of a compatible clinical setting (cardiocirculatory failure or arterial hypoxemia) and aminotransferase levels higher than 1000 IU/L.

RESULTS

During the 8-year study period, 182 out of the 7674 patients admitted presented hypoxic hepatitis (2.4%). The most common cause was septic shock. The rate of in-hospital mortality in hypoxic hepatitis was 61.5% (112 patients), and was higher in patients with septic shock (83.3%) and cardiac arrest (77.7%). Ischemic pancreatitis (25.6%), rhabdomyolysis (41.2%) and renal failure (67.2%) were common in these patients. Risk factors of mortality were prolonged INR (p = 0.005), need for renal replacement therapy (p = 0.001) and septic shock (p = 0.005).

CONCLUSIONS

Hypoxic hepatitis was not a rare condition, and was frequently accompanied by multiorgan injury, with high mortality. Risk factors for increased mortality were prolonged INR, need for renal replacement therapy, and septic shock.