Journal of Intensive Care Medicine recent issues

Analytic Review: Hyponatremia in Heart Failure

Chatterjee, K. — Wed, 18 Nov 2009 23:09:05 PST

Hyponatremia is one of the newer and emerging risk factors for an adverse prognosis in chronic heart failure. Why decreased serum sodium is associated with worse prognosis remains unclear. It may reflect worsening heart failure and the deleterious effects of activation of neurohormones. The mechanism of hyponatremia in heart failure also remains unclear. A relatively greater degree of free-water retention compared to sodium retention is probably the major mechanism. The treatment of significant hyponatremia in heart failure is difficult. The conventional treatments such as fluid restriction, infusion of hypertonic saline, and aggressive diuretic therapies are not usually effective. Vasopressin receptor antagonists have been shown to enhance aquaresis and correct hyponatremia. However, long-term beneficial effects of such treatments in chronic heart failure have not been documented.

A Simple Physiologic Algorithm for Managing Hemodynamics Using Stroke Volume and Stroke Volume Variation: Physiologic Optimization Program

McGee, W. T. — Wed, 18 Nov 2009 23:09:05 PST

Intravascular volume status and volume responsiveness continue to be important questions for the management of critically ill or injured patients. Goal-directed hemodynamic therapy has been shown to be of benefit to patients with severe sepsis and septic shock, acute lung injury and adult respiratory distress syndrome, and for surgical patients in the operating room. Static measures of fluid status, central venous pressure (CVP), and pulmonary artery occlusion pressure (PAOP) are not useful in predicting volume responsiveness. Stroke volume variation and pulse pressure variation related to changes in stroke volume during positive pressure ventilation predict fluid responsiveness and represent an evolving practice for volume management in the intensive care unit (ICU) or operating room. Adoption of dynamic parameters for volume management has been inconsistent. This manuscript reviews some of the basic physiology regarding the use of stroke volume variation to predict fluid responsiveness in the ICU and operating room. A management algorithm using this physiology is proposed for the critically ill or injured in various settings.

Inhalational Anesthesia: Basic Pharmacology, End Organ Effects, and Applications in the Treatment of Status Asthmaticus

Tobias, J. D. — Wed, 18 Nov 2009 23:09:05 PST

The potent inhalational anesthetic agents are used on a daily basis to provide intraoperative anesthesia. Given their beneficial effects on airway tone and reactivity, they also have a role in the treatment of status asthmaticus that is refractory to standard therapy. Although generally not of clinical significance, these agents can affect various physiological functions. The potent inhalational anesthetic agents decrease mean arterial pressure and myocardial contractility. The decrease in mean arterial pressure reduces renal and hepatic blood flow. Secondary effects on end-organ function may result from the metabolism of these agents and the release of inorganic fluoride. The following article reviews the history of inhalational anesthesia, the physical structure of the inhalational anesthetic agents, their end-organ effects, reports of their use for the treatment of refractory status asthmaticus in the intensive care unit (ICU) patient, and special considerations for their administration in this setting including equipment for their delivery, scavenging, and monitoring.

The Role of Head Computer Tomographic Scans on the Management of MICU Patients With Neurological Dysfunction

Salerno, D., Marik, P. E., Daskalakis, C., Kolm, P., Leone, F. — Wed, 18 Nov 2009 23:09:05 PST

Neurological dysfunction is common in patients admitted to the medical intensive care unit (MICU). However, the indications for head imaging in those patients are unclear. The objective of this study was to assess whether clinical variables would be useful in selecting patients who are likely to have an abnormality on head computerized tomographic (CT) scanning and to determine the impact of such scans on management decisions. We reviewed the charts of 740 patients admitted to our MICU between October 2002 and July 2004. A total of 123 patients (16.6%) had a head CT scan performed, with a new finding being present in 26 (21.1%) patients. In the patients with a new CT finding, there was a change in diagnosis in 11 (42%) patients and a change in treatment in 6 (23%) patients. Logistic regression analysis failed to determine any clinical characteristic that could predict a new finding on the CT scan. This study suggests that clinicians should have a low threshold for ordering a CT scan in MICU patients with acute neurological dysfunction.

Acute Hemodynamic Effects of Recruitment Maneuvers in Patients With Acute Respiratory Distress Syndrome

Wed, 18 Nov 2009 23:09:05 PST

Background: The recruitment maneuver (RM) in acute respiratory distress syndrome (ARDS) can cause hemodynamic derangement. We evaluated circulatory and cardiac changes during RMs.

Methods: We performed sustained inflation (SI) with a pressure of 40 cm H₂O for 30 seconds as an RM on 22 patients with ARDS. Blood pressure (BP) and heart rate were recorded immediately before, every 10 seconds during, and 30 seconds after the RM. Ventricular dimensions were obtained simultaneously using M-mode echocardiography, and tissue Doppler imaging was performed on the left ventricular wall.

Results: Mean, systolic, and diastolic BP decreased at 20 and 30 seconds during 30-second RMs (mean BP: 92 ± 12 at baseline to 83 ± 18 mm Hg at the end of the RM, P < .05) and subsequently recovered. Heart rate decreased at 10 and 20 seconds during the RM, and tended to increase afterward. Both ventricular dimensions decreased significantly during the RM. The left ventricular ejection fraction and peak velocity of the left ventricle during systole remained stable. The fractional changes in mean BP and left ventricular end-diastolic dimension during the RMs were correlated significantly with each other (r_s = 0.59). Static compliance of the respiratory system (Crs) was lower in patients with mean BP change ≥15% than in patients in whom the change was <15% (P < .05).

Conclusions: A transient decrease in mean BP was observed during the RM, and its degree was correlated with the preload decrease, while cardiac contractility was maintained.

Bi-Level Positive Airway Pressure Ventilation in Pediatric Oncology Patients With Acute Respiratory Failure

Schiller, O., Schonfeld, T., Yaniv, I., Stein, J., Kadmon, G., Nahum, E. — Wed, 18 Nov 2009 23:09:05 PST

The aim of the study was to describe our experience with bi-level positive airway pressure (BiPAP) ventilation in oncology children with acute respiratory failure, hospitalized in a single tertiary pediatric tertiary center. This was a retrospective cohort study of all pediatric oncology patients in our center admitted to the intensive care unit with acute hypoxemic or hypercarbic respiratory failure from January 1999 through May 2006, who required mechanical ventilation with BiPAP. Fourteen patients met the inclusion criteria with a total of 16 events of respiratory failure or impending failure: 12 events were hypoxemic, 1 was combined hypercarbic and hypoxemic, and 3 had severe respiratory distress. Shortly after BiPAP ventilation initiation, there was a statistically significant improvement in the respiratory rate (40.4 ± 9.3 to 32.5 ± 10.1, P < .05] and a trend toward improvement in arterial partial pressure of oxygen (PaO₂; 71.3 ± 32.7 to 104.6 ± 45.6, P = .055). The improvement in the respiratory status was sustained for at least 12 hours. In 12 (75%) events there was a need for sedation during ventilation; 12 children needed inotropic support during the BiPAP ventilation. Bi-level positive airway pressure ventilation failed in 3 (21%) children who were switched to conventional ventilation. All of them have died during the following days. One child was recategorized to receive palliative care while on BiPAP ventilator and was not intubated. In 12 of 16 BiPAP interventions (75%; 11 patients), the children survived to pediatric intensive care unit (PICU) discharge without invasive ventilation. No major complications were noted during BiPAP ventilation. Bi-level positive airway pressure ventilation is well tolerated in pediatric oncology patients suffering from acute respiratory failure and may offer noninferior outcomes compared with those previously described for conventional invasive ventilation. It appears to be a feasible initial option in children with malignancy experiencing acute respiratory failure.

Circulatory Arrest in a Brain-Dead Organ Donor: Is the Use of Cardiac Compression Permissible?

Cummings, B., Noviski, N., Moreland, M. P., Paris, J. J. — Wed, 18 Nov 2009 23:09:05 PST

Care of the brain-dead patient is common in intensive care practice. Aggressive donor management is advocated to increase supply of viable organs. Significant controversy exists over cardiac resuscitation in patients determined dead by cardiac criteria. The issue, till now, has not been addressed in brain dead patients. We discuss a case of cardiac resuscitation of a brain-dead donor to ensure organ donation. This case allows us to examine the use of brain death criteria to declare death, the controversy regarding cardiac resuscitation in organ donor patients, and the standards for use of cardiac resuscitation in the organ donor declared dead by brain death criteria. The consent process for organ donation in brain dead patients should address the possibility of subsequent cardiac arrest.

Respect for Persons: Beyond the Mortal World

Bierer, G. — Wed, 18 Nov 2009 23:09:05 PST

Neuroimaging in the Medical Intensive Care Unit: An Essential Complement to the Clinical Examination

Lee, K., Badjatia, N. — Wed, 18 Nov 2009 23:09:05 PST

Analytic Review: Confirmation of Endotracheal Tube Position: A Narrative Review

Rudraraju, P., Eisen, L. A. — Fri, 18 Sep 2009 04:33:54 PDT

Endotracheal tube (ETT) insertion is the primary method of definitive airway protection and control in critically ill patients. Detection of ETT malposition in a timely fashion is crucial in both elective and emergent intubation. In this review, we describe classic tests and highlight several new technologies that may assist the practitioner in determining ETT position within the esophago-tracheal complex, namely ultrasonographic and impedance-based methods. Strengths and weaknesses of particular methods are highlighted. Although many physical examination maneuvers have been described, reliance on the physical examination alone is insufficient for confirmation. Touted methods that appear failsafe, such as direct visualization of the ETT traversing the vocal cords have limitations, especially when dealing in the emergency setting accompanying a difficult to visualize airway. While carbon dioxide detection is an excellent confirmatory method, it is not infallible. Esophageal detection devices are useful as an alternative means of confirmation. New methods such as ultrasonic location of the ETT show promise but require further study. The clinician performing ETT insertion should have multiple confirmation methods that allow the practitioner to adapt to a variety of clinical situations, depending on local costs and availability. Finally, when the clinician still has uncertainty, or multiple tests give conflicting results, the availability of bronchoscopy at the bedside to visualize the carina through the ETT is useful.

Sympathetic Overstimulation During Critical Illness: Adverse Effects of Adrenergic Stress

Dunser, M. W., Hasibeder, W. R. — Fri, 18 Sep 2009 04:33:54 PDT

The term ‘‘adrenergic’’ originates from ‘‘adrenaline’’ and describes hormones or drugs whose effects are similar to those of epinephrine. Adrenergic stress is mediated by stimulation of adrenergic receptors and activation of post-receptor pathways. Critical illness is a potent stimulus of the sympathetic nervous system. It is undisputable that the adrenergic-driven ‘‘fight-flight response’’ is a physiologically meaningful reaction allowing humans to survive during evolution. However, in critical illness an overshooting stimulation of the sympathetic nervous system may well exceed in time and scope its beneficial effects. Comparable to the overwhelming immune response during sepsis, adrenergic stress in critical illness may get out of control and cause adverse effects. Several organ systems may be affected. The heart seems to be most susceptible to sympathetic overstimulation. Detrimental effects include impaired diastolic function, tachycardia and tachyarrhythmia, myocardial ischemia, stunning, apoptosis and necrosis. Adverse catecholamine effects have been observed in other organs such as the lungs (pulmonary edema, elevated pulmonary arterial pressures), the coagulation (hypercoagulability, thrombus formation), gastrointestinal (hypoperfusion, inhibition of peristalsis), endocrinologic (decreased prolactin, thyroid and growth hormone secretion) and immune systems (immunomodulation, stimulation of bacterial growth), and metabolism (increase in cell energy expenditure, hyperglycemia, catabolism, lipolysis, hyperlactatemia, electrolyte changes), bone marrow (anemia), and skeletal muscles (apoptosis). Potential therapeutic options to reduce excessive adrenergic stress comprise temperature and heart rate control, adequate use of sedative/analgesic drugs, and aiming for reasonable cardiovascular targets, adequate fluid therapy, use of levosimendan, hydrocortisone or supplementary arginine vasopressin.

Fever During Pediatric Intensive Care Unit Admission Is Independently Associated With Increased Morbidity

Gordijn, M. S., Plotz, F. B., Kneyber, M. C. J. — Fri, 18 Sep 2009 04:33:54 PDT

Aims: To investigate the occurrence and etiology of fever at anytime during pediatric intensive care unit (PICU) admission, and to study its possible effects on clinical outcome in a heterogeneous population of critically ill children. Methods: Retrospective, observational single-center study, comprising 202 patients aged 0 to 18 years, admitted during a 6-month period between January and June 2004. Demographic and clinical data were collected. Fever was defined by a core temperature ≥38.3°C. Outcomes of interest were duration of mechanical ventilation (MV) and PICU stay. Statistical analyses were done using nonparametric univariate analysis and multivariate Cox’s regression analysis. Results: Fever during PICU stay occurred in 82 of 202 children (40.6%). Demographic, clinical, and laboratory data of febrile patients were compared to data of nonfebrile patients. In 76 of the febrile patients (92.7%), fever occurred in the first 48 hours of admission and was associated with primary diagnosis in all cases. Six patients developed fever after 48 hours of admission and 8 patients developed a new febrile period after 48 nonfebrile hours. At least 50% of the late-onset fever was caused by cultured proven nosocomial infections, in the other cases a nosocomial infection was suspected. Fever after 48 hours of PICU admission or a secondary episode of fever was independently associated with prolonged length of ventilatory support and prolonged length of PICU stay. Conclusions: Fever in critically ill children occurs frequently during PICU stay. Fever after 48 hours of admission or new episodes of fever after 48 nonfebrile hours were mainly caused by nosocomial infections and was independently associated with prolonged length of ventilatory support and PICU stay.

Children With Respiratory Distress Treated With High-Flow Nasal Cannula

Spentzas, T., Minarik, M., Patters, A. B., Vinson, B., Stidham, G. — Fri, 18 Sep 2009 04:33:54 PDT

High-flow nasal cannula (HFNC) therapy is a treatment for respiratory distress in neonates and children. In the present study, we assessed its effectiveness, comfort, and possible mechanism of action. Methods: We reviewed records of 46 patients treated with HFNC and estimated the modified COMFORT score (7 to 35 units), the respiratory clinical scale (0 to 12 units), and the oxygen saturation level. Data were collected at time 0 (before the use of high-flow), time 2 (60 to 90 min post-application), and at time 3 (8 to 12 hours post-application). Furthermore, we measured the nasopharyngeal pressure while on continuous positive air pressure (CPAP) as well as the differences in ‘‘lung expansion’’ demonstrated by the prestudy and post-study chest x-ray. Results: There were significant improvements in the modified COMFORT score (F_1,45 = 40.03, P < .05), respiratory clinical scale (F_1.69,76.15 = 121.19, P < .05), and oxygen saturation (F_2,90 = 101.54, P < .05). Application of HFNC therapy created a significant average positive expiratory pressure of 4.0 ± 1.99 (SE) cm H₂O. X-rays taken after initiation of HFNC showed either improved aeration of the lungs or no changes in 40 of 46 patients. Mechanical ventilation was needed in 5 of 46 patients. Conclusion: Our study indicates that high-flow nasal cannula improves the respiratory scale score, the oxygen saturation, and the patient’s COMFORT scale. Its mechanism of action is application of mild positive airway pressure and lung volume recruitment.

Techniques for Assessment of Intravascular Volume in Critically Ill Patients

Marik, P. E. — Fri, 18 Sep 2009 04:33:54 PDT

Fluid replacement is considered the cornerstone of resuscitation in the ICU. However, only about 50% of critically ill hemodynamically unstable patients are fluid responsive; furthermore, both under-resuscitation and overzealous fluid administration adversely affect outcome Consequently, the resuscitation of critically ill patients requires an accurate assessment of the patients’ intravascular volume status and their volume responsiveness. This paper reviews the evolution and accuracy of methods for assessing fluid responsiveness in critically ill patients.

Can a broken heart be fixed?

Shamloo, B., Taylor, J. L., Yusufali, T., D' Attellis, N. — Fri, 18 Sep 2009 04:33:54 PDT

Analytic Reviews: High-Frequency Oscillatory Ventilation (HFOV) and Airway Pressure Release Ventilation (APRV): A Practical Guide

Stawicki, S.P., Goyal, M., Sarani, B. — Tue, 21 Jul 2009 21:07:17 PDT

Despite advances in ventilator management, 31% to 38% of patients with adult respiratory distress syndrome (ARDS) will die, some from progressive respiratory failure. Inability to adequately oxygenate patients with severe ARDS has prompted extensive efforts to identify what are now known as alternative modes of ventilation including high-frequency oscillatory ventilation and airway pressure release ventilation. Both modalities are based on the principles of the open-lung concept and aim to improve oxygenation by keeping the lung uniformly inflated for an extended period of time. Although a mortality benefit has not been proven, some patients may benefit from these alternative modes of ventilation as rescue measures while the underlying process resolves. The purpose of this article is to review the evidence and mechanisms underlying each modality and to describe the fundamental steps in initiating, adjusting, and terminating these modes of ventilation.

The Use of Carbapenems in the Treatment of Serious Infections

Baughman, R. P. — Tue, 21 Jul 2009 21:07:17 PDT

Inadequate initial antimicrobial treatment in serious infections leads to increased mortality. Achieving adequate treatment is increasingly difficult because of the increasing prevalence of multidrug-resistant (MDR) pathogens. The carbapenems are potent, broad-spectrum antibiotics that have been shown to be safe and efficacious therapies in the treatment of serious infections. This review is intended to compare the 4 major members of the carbapenem class, which include imipenem, meropenem, ertapenem, and doripenem, with other widely used antimicrobial agents in the intensive care unit (ICU). The carbapenems are potent, broad-spectrum antibiotics that have been shown to be safe and efficacious therapies in the treatment of serious infections. They provide better gram-negative coverage than other β-lactams and are stable against extended-spectrum β-lactamases and AmpC β-lactamases, making them effective in the treatment of many MDR bacteria. The newly approved carbapenem, doripenem, may help preserve the utility of the carbapenem class.

Review of a Large Clinical Series: Insulin Resistance Despite Tight Glucose Control Is Associated With Mortality in Critically Ill Surgical Patients

Tue, 21 Jul 2009 21:07:17 PDT

Background: The hyperglycemic state following trauma and surgery is related partially to insulin resistance (IR). The objective is to determine if critically ill surgical patients vary in their extent of IR and is IR associated with mortality. Methods: Prospective observational study in trauma and surgical intensive care units. There were 925 ventilated, critically ill surgical patients who were placed on an automated euglycemia protocol. A mathematic multiplier (M) employed by the protocol was used as a measure of IR. Outcome, phenotypic, laboratory, and treatment variables were analyzed. Results: 54,141 entries for glucose (mg/dl) and M were analyzed. Median glucose was 118mg/dL, with 45% of values between 80-110mg/dL, 81% between 80-150 mg/dL, and 0.2% less than 40 mg/ dL. M varied by 42 fold over the entire population, and by an average of 11-fold among individual patients. The median blood glucose was not different between groups (118 mg/dl for survivors and 118 mg/dl for non-survivors, P = 0.36). The median insulin dose and M were significantly higher in non-survivors (4.1 U/hr versus 3.4 U/hr, P = 0.005; 0.061 versus 0.058, P = 0.02). Conclusions: There was a large amount of variation in insulin resistance, as measured by an adapting multiplier, both across the population and within patients. In the setting of tight glucose control measures of glucose control (median blood glucose and percent in range) do not differentiate between patients who lived and died while measures of insulin resistance (median insulin dose and multiplier) do, suggesting that the insulin resistance is a better predictor of outcome.

Increased Oxidants and Reduced Antioxidants in Irradiated Parenteral Nutrition Solutions May Contribute to the Inflammatory Response

Tue, 21 Jul 2009 21:07:17 PDT

Background/Objectives: To measure reactive oxidant production and the decline in antioxidant potential in commercially available, irradiated parenteral nutrition (PN) solutions and the effect that these have on oxidant production in patients in the intensive care unit. Subjects and Methods: Vitamin E and malondialdehyde in irradiated and nonirradiated commercially available, PN solutions were measured. The PBN (-phenyl-n-test-butylnitrone (PBN) spin trap was used to measure free radicals and TEMPOL (2,2,6,6-tetramethyl-4-hydroxy-piperidine-oxyl) was used to assess antioxidant capacity. The irradiated PN was administered (as per unit protocol) to 10 patients with gut failure and plasma and urinary isoprostanes and interleukin-6 (IL-6) were measured 1 hour preadministration, at the time of, and 1 and 2 hours postadministration of PN. Results: Irradiation reduced vitamin E significantly (P < .0025). Malondialdehyde products were present in both samples, but more so in irradiated samples (P < .0001), as were free radicals measured by PBN spin trapping. Irradiated samples had a higher scavenging capacity of TEMPOL free radical due to depletion of antioxidants in irradiated samples. Urinary isoprostanes increased at time 2 by 6.3 units relative to time 0 and by 5.23 units relative to time 1(Friedman ANOVA: P < .01413). Conclusions: Lipid hydroperoxides are formed in PN solutions and increase further following irradiation. This is associated with a significant reduction in vitamin E and antioxidant potential. The increase in urinary isoprostanes indicates a potentially proinflammatory effect of irradiated PN.

A Comparison of Infusion Volumes in the Measurement of Intra-Abdominal Pressure

Tue, 21 Jul 2009 21:07:17 PDT

Bladder pressure measurement through a foley catheter is the current standard in monitoring for intraabdominal hypertension (IAH) and abdominal compartment syndrome (ACS). Accurate pressure transduction requires a continuous fluid column with a small volume of transducing medium at the tip of the catheter. Infusing excessive fluid volume can falsely elevate the measured intra-abdominal pressure (IAP) due to bladder overdistention and can lead to intrinsic muscular contraction. This effect can be seen with volumes as low as 60 mL. Recent expert consensus has recommended 25 mL as the maximal infusion volume; however, 50 mL is the most commonly cited volume of infusion in the literature. The purpose of this analysis was to determine the variance between IAP values using a range of volume infusions between 10 and 60 mL. Eighteen adult, surgical intensive care unit (SICU) patients who were undergoing IAP measurement for IAH or clinically indicated monitoring were enrolled in a prospective, nontreatment study. Intra-abdominal pressure measurements were obtained with stepwise increases of injectate volume from 10 to 60 mL (in 10 mL increments). Bland-Altman analyses and receiver operating characteristic (ROC) curves were used for analysis. After analysis accounting for data correlation within patients, means and standard deviations were generated for differences between 50 mL and 10, 20, 30, 40, and 60 mL bladder infusion volumes. Bland-Altman analyses showed good agreement between measurements and no significant difference in variance (mean ≤1.35 mm Hg) between volume comparisons. The ROC curve generated for each test volume using a diagnostic pressure value for IAH (!12 mm Hg) showed that a value between 11 and 12 mm Hg gave the best combination of sensitivity and specificity for all test volumes. In SICU patients, with a clinical indication for IAP monitoring, bladder infusion volumes between 10 mL and 60 mL provide consistent IAP measurements.

Massive Cerebrovascular Infarct Due to the Catastrophic Antiphospholipid Syndrome in a Patient With Idiopathic Thrombocytopenic Purpura

Modrykamien, A., Reddy, A., Guzman, J. A., Farha, S. — Tue, 21 Jul 2009 21:07:17 PDT

Catastrophic antiphospholipid syndrome (APS) is caused by thrombotic vascular occlusions that affect both small and large vessels, producing ischemia in the affected organs as well as a systemic inflammatory response syndrome (SIRS). We report a case of a patient with idiopathic thrombocytopenic purpura (ITP) who developed massive cerebral ischemia due to this entity. Prompt and aggressive treatment may prevent and actually resolve lethal complications caused by this devastating syndrome.

Intraoperative Diagnosis of Unsuspected Methemoglobinemia Due to Low Pulse Oximetry Values

Tobias, J. D., Ramachandran, V. — Tue, 21 Jul 2009 21:07:17 PDT

Methemoglobinemia results from the oxidation of the iron in the hemoglobin molecule from the ferrous to the ferric state. Methemoglobinemia may result from congenital deficiencies of enzymes that normally convert methemoglobin (metHb) to hemoglobin, alterations in the hemoglobin molecule itself or, most commonly, from medications or toxins. As metHb cannot carry oxygen, clinical sequelae result when the concentration of metHb is high enough to compromise oxygen delivery to the tissues. With low levels, the patient may be asymptomatic or only symptomatic during periods of increased tissue oxygen demands such as exercise. With higher levels, symptoms may occur at rest. We describe an adolescent with acute leukemia who presented to the operating room for placement of a Broviac catheter for permanent central venous access. Given a persistently low oxygen saturation as measured by pulse oximetry (92% to 94%) with no response to changes in the inspired oxygen concentration and the lack of physical findings on auscultation to explain the low oxygen saturation, the diagnosis of metHb was entertained and confirmed by laboratory analysis.

Book Review: The Trauma Manual: Trauma and Acute Care Surgery, 3rd Edition By Andrew Peitzman B. et al Lippincott, Williams & Wilkins, 2007. Price of Book: $49.95

DeRoss, A. L. — Tue, 21 Jul 2009 21:07:17 PDT

Analytic Review: The Pathogenetic and Prognostic Value of Biologic Markers in Acute Lung Injury

Levitt, J. E., Gould, M. K., Ware, L. B., Matthay, M. A. — Thu, 21 May 2009 04:00:21 PDT

Over the past 2 decades, measurement of biomarkers in both the airspaces and plasma early in the course of acute lung injury has provided new insights into the mechanisms of lung injury. In addition, biologic markers of cell-specific injury, acute inflammation, and altered coagulation correlate with mortality from acute lung injury in several single center studies as well as in multicenter clinical trials. To date, biomarkers have been measured largely for research purposes. However, with improved understanding of their role in the pathogenesis of acute lung injury, biomarkers may play an important role in early detection of lung injury, risk stratification for clinical trials, and, ultimately, tailoring specific therapies to individual patients. This article provides a review of biologic markers in acute lung injury, with an emphasis on recent analysis of results from multicenter clinical trials.

Decompressive Surgery for Severe Brain Edema

Diedler, J., Sykora, M., Blatow, M., Juttler, E., Unterberg, A., Hacke, W. — Thu, 21 May 2009 04:00:22 PDT

Decompressive surgery has since long been a promising therapeutic approach for patients with acute severe brain injury at risk to develop severe brain edema. The underlying rationale of removing part of the cranium is to create space for the expanding brain to prevent secondary damage to vital brain tissue. However, until recently, randomized controlled trials that demonstrate the efficacy of decompressive surgery or benefit for outcome were missing. This has changed since the results of 3 randomized trials on hemicraniectomy in malignant infarction of the middle cerebral artery have been published in 2007. In this article, the current evidence for decompressive surgery in the treatment of cerebral ischemia, intracranial hemorrhage, traumatic brain injury, inflammatory diseases, or severe metabolic derangements is reviewed. Although there is increasing evidence for the efficacy of decompressive surgery in reducing intracranial pressure and even mortality, a critical point remains the definition of good or acceptable outcome.

Review of A Large Clinical Series: Coronary Angiography Predicts Improved Outcome Following Cardiac Arrest: Propensity-adjusted Analysis

Thu, 21 May 2009 04:00:22 PDT

Objectives: Determine if clinical parameters of resuscitated patients predict coronary angiography (CATH) performance and if receiving CATH after cardiac arrest is associated with outcome. Introduction: CATH is associated with survival in patients suffering out-of-hospital cardiac arrest (OHCA) from ventricular fibrillation or ventricular tachycardia(VF/VT). Its effect on outcome in other cohorts is unknown. Methods: Chart review of resuscitated cardiac arrest patients between 2005 and 2007. Exclusion criteria: immediate withdrawal of care, hemodynamic collapse, or neurologic exam under sedation. Clinical parameters included Glasgow Coma Scale (GCS) arrest location, presenting rhythm, age, and acute ischemic ECG changes (new left bundle branch block or ST-elevation myocardial infarction-STEMI). Logistic regression identified clinical parameters predicting CATH. The association between CATH and good outcome (discharge home or to acute rehabilitation facility) was determined using logistic regression adjusting for likelihood of receiving CATH via propensity score. Result: Of the 241 patients, 96 (40%) received CATH. Significant disease (≥70% stenosis) of ≥1 coronary arteries was identified in 69% of patients including 57% of patients without acute ischemic ECG changes. Unadjusted predictors of CATH were sex, method of arrival, OHCA, presenting rhythm, acute ischemic ECG changes, and GCS. Propensity adjusted logistic regression demonstrated an association between CATH and good outcome (OR 2.16; 95% CI 1.12, 4.19; P < 0.02). Conclusion: CATH is more likely to be performed in certain patients and identifies a significant number of high-grade stenoses in this population. Receiving CATH was independently associated with good outcome.

Decannulation Following Tracheostomy for Prolonged Mechanical Ventilation

O'Connor, H. H., Kirby, K. J., Terrin, N., Hill, N. S., White, A. C. — Thu, 21 May 2009 04:00:22 PDT

Background: We examined the process of decannulation following tracheostomy in patients transferred to a long-term acute care (LTAC) hospital for weaning from prolonged mechanical ventilation (PMV). Methods: A retrospective chart review of 135 patients. Results: Decannulation was successful in 35% of patients a median of 45 days (IQR, 32-76) following tracheostomy. Patients who failed decannulation had a tracheostomy tube placed earlier (14 days; IQR 11-18 vs. 18 days; IQR 14-30, P = .04) and had a shorter length of stay at the acute facility (20 days; IQR, 16-23 vs. 31 days; IQR, 24-45, P = .003) compared with patients who were decannulated. Length of stay and cost of care at the LTAC did not differ with decannulation status. At 3.5 years, 35% (47/135) of all patients and 62% (29/47) of decannulated patients were alive. Conclusions: Decannulation was achieved in 35% of patients transferred to an LTAC for weaning from prolonged mechanical ventilation.

Design and Development of a Cardiopulmonary Resuscitation Mattress

Thu, 21 May 2009 04:00:22 PDT

This study introduces the design and construction of a mattress insert to produce more effective cardiopulmonary resuscitation (CPR). The mattress insert deflates, making the mattress insert a rigid surface. Using a device that administers a constant compression depth onto a manikin, we were able to show that our mattress insert more effectively directed the compressive force to the manikin compared to the current practice of using a headboard on top of a mattress. The mattress insert produced a statistically significant increase in the compression efficiency when compared to the current practice of using the headboard (81% vs. 53%). Because the mattress insert starts deflating immediately after the vacuum is turned on, 1 person is needed to initiate chest compressions. Compression begins while the mattress deflates. Running compression tests at incremental time periods, we found that our design reaches and surpasses the compression efficiency when using a headboard in 10 seconds.

30-Year-old HIV-positive Female With Diffuse Alveolar Hemorrhage

Agarwal, V. K., Khurana, H. S., Le, H. X., Mathisen, G., Kamangar, N. — Thu, 21 May 2009 04:00:22 PDT

We present a case of Strongyloides stercoralis hyperinfection in a 30-year-old HIV positive female who presents with diffuse alveolar hemorrhage. We discuss the relevant differential diagnoses and characteristic imaging findings.

A Case of Kombucha Tea Toxicity

SungHee Kole, A., Jones, H. D., Christensen, R., Gladstein, J. — Thu, 21 May 2009 04:00:22 PDT

Introduction: Kombucha ``mushroom'' tea is touted to have medicinal properties. Here, we present a case of hyperthermia, lactic acidosis, and acute renal failure within 15 hours of Kombucha tea ingestion. Case Presentation: A 22 year old male, newly diagnosed with HIV, became short of breath and febrile to 103.0F, within twelve hours of Kombucha tea ingestion. He subsequently became combative and confused, requiring sedation and intubation for airway control. Laboratories revealed a lactate of 12.9 mmol/L, and serum creatinine of 2.1 mg/dL. Discussion: Kombucha tea is black tea fermented in a yeast-bacteria medium. Several case reports exist of serious, and sometimes fatal, hepatic dysfunction and lactic acidosis within close proximity to ingestion. Conclusion: While Kombucha tea is considered a healthy elixir, the limited evidence currently available raises considerable concern that it may pose serious health risks. Consumption of this tea should be discouraged, as it may be associated with life-threatening lactic acidosis.

In-hospital CPR: Performing it Better but Less Often

Nader, A., Seneff, M. G. — Thu, 21 May 2009 04:00:22 PDT

The Rapidly Expanding Therapeutic Role of Thymosin {alpha}-1 in the Management of Gastrointestinal and Systemic Infectious Disorders

Kapoor, S. — Thu, 21 May 2009 04:00:22 PDT