Speciality
Spotlight

   




   


Surgery


   

 





critical
care

     

  • J
    Briegel, H Forst, M Haller, et al (Ludwig-Maximilians-Universitat
    Munchen, Munich)

    Stress
    Doses of Hydrocortisone Reverse Hyperdynamic Septic
    Shock: A Prospective, Randomized, Double-blind,
    Single-center Study.

    Crit Care Med 27:723-732, 1999.

         

    Past
    studies have showed that stress doses of
    hydrocortisone were ineffective in septic shock. However, recent studies have shown that a patient in septic shock
    may have relative adrenocortical insufficiency.

        

    In
    septic shock, a 100mg loading dose of hydrocortisone
    was given within 30 min, and followed by an infusion
    of (0.18mg/kg/hr) hydrocortisone.
    After reversal of shock, the dose was reduced
    to 0.08mg/kg/hr and continued for 6 days.

        

    This
    significantly reduces the duration of vasopressor
    support and may shorten the time for resolution of
    sepsis induced organ dysfunction.

           

  • MB
    Malay, Jr Ashton RC, DW Landry, et al (Allegheny Gen
    Hosp, Pittsburgh, Pa; Columbia, Univ, New York)

    Low-Dose
    Vasopressin in the Treatment of Vasodilatory Septic
    Shock

    J Trauma  47: 699-705, 1999.

        

    Refractory
    hypotension not responding to epinephrine in septic
    shock is potentially fatal.
    It has been suggested that vasopressin used
    concomitantly could give better results.

       

    The
    vasopressor was infused at a rate of 0.04U/min.
    This permitted maintenance of arterial
    pressure thus allowing withdrawal of vasopressors.

          

  • MWA
    Angstwurm, J Schottdorf, J Schopohl, et la (Univ of
    Munich, Germany)

    Selenium Replacement in Patients with Severe Systemic Inflammatory
    Response Syndrome Improves Clinical Outcome.

    Crit Care Med 27: 1807-1813, 1999.

       

    Systemic
    inflammatory response syndrome (SIRS) causes
    substantial morbidity and mortality. It has also
    been recorded that selenium concentrations are
    reduced in SIRS. This
    is a pilot study on the effects of selenium
    replacement on SIRS related morbidity and mortality.

        

    Selenium
    was replaced as i.v. sodium selenite in a decreasing
    dosage over a period of 10 days.

         

    Within
    30 days, patients had normal selenium and
    glutathione peroxidose levels.
    There was significant reduction in Acute
    Physiologic and Chronic Health Evaluation III scores
    as compared to controls.
    Only 14% (as against 43% in controls) had
    renal failure and the mortality was 34% against 54%
    in the control group.

         

  • JE
    Gadek, and the Enteral Nutrition in ARDS Study Group
    (Ohio State Univ, Columbus; et al )

    Effect
    of Enteral Feeding with Eicosapentaenoic Acid,
    g-Linolenic
    Acid, and Antioxidants in Patients with Acute
    Respiratory Distress Syndrome.

    Crit Care Med  27:
    1409-1420, 1999.

       

    Low
    carbohydrate, high fat nutritional support for
    ventilated patients reduces demands on the
    respiratory system and decreases the severity of the
    inflammatory injury.
    Animal studies show that diets rich in
    eicosapentaenoic acid,
    g-linolenic
    acid and antioxidants can moderate inflammation.
    This is a prospective double blind randomized
    controlled trial (multi-centered) to evaluate the
    effect of a diet supplemented with EPA, GLA and
    antioxidants on the clinical outcome of ARDS.

       

    The
    patients on the test diet required fewer days of
    ventilatory support in ICU or on supplemental oxygen
    and had less new organ failure.
    The infection rates were the same but the
    test diet patients had fewer adverse events.

         

  • VM
    Ranieri, PM Suter, C Tortorella, et al (Univ of
    Toronto)

    Effect
    of Mechanical Ventilation on Inflammatory Mediators
    in Patients with Acute Respiratory Distress
    Syndrome: A Randomized Controlled Trial.

    JAMA 282:54-61, 1999

       

    Mechanical
    ventilation can escalate or cause an inflammatory
    response and acute lung injury.
    The influence of mechanical ventilation on
    the lung and systemic cytokine release was assessed
    in patients with ARDS.

      

    Two
    groups were assessed (1) a control group and (2) a
    lung protective strategy group.

      

    At
    baseline physiologic characteristics and cytokine
    concentrations were similar.
    But after 24 and 36 hours, there were
    significant between-group differences in tidal
    volume, end-inspiratory plateau pressures and PEEP. The lung protective strategy group had significantly better
    results. It
    could be concluded that mechanical ventilation can
    produce a cytokine response that may be diminished
    by minimising overdistension and recruitment and
    derecruitment of the lung.

         

  • PC
    Hebert, for the Canadian Critical Care Trials Group
    (Univ of Ottawa, Canada; et al)

    A
    Multicenter, Randomized, Controlled Clinical Trial
    of Transfusion Requirements in Critical Care,

    N Engl J Med 340: 409-417, 1999.

      

    The
    optimal transfusion strategy for cirtically ill
    anaemia patients has not been standardised.
    A randomised, controlled study was undertaken
    comparing a restrictive (when Hb <7.0gms/dL) with
    a liberal approach (when Hb <10gms/dL).

      

    The study was conducted on 838 critically ill
    patients randomly assigned to one of the two groups.

      

    The
    overall 30 days mortality was similar.
    Mortality rates were significantly lower in
    the restrictive group in less acutely ill patients
    but was similar in critically ill patients.
    The mortality during hospitalization was
    significantly lower in the restrictive group.

        

  • S
    Deb, B Martin, L Sun, et al (Natl Naval Med Ctr,
    Bethesdam Md; Walter Reed Army Med Ctr, Washington,
    DC; Uniformed Services Univ of the Health
    Sciences, Bethesda, Md)

    Resuscitation
    With Lactated Ringer’s Solution in Rats with
    Hemorrhagic Shock Induces Immediate Apoptosis.

    J Trauma: Injury Infect Crit Care  46:
    582-589, 1999.

      

    For
    patients in haemorrhagic shock, reperfusion injury
    can cause cell damage, leading to cell death and
    organ failure. Apoptotic
    cell death is thought to play an important role in
    the pathophysiology of haemorrhagic shock.
    The effects of resuscitation with lactated
    Ringer’s solution on cell apoptosis were assessed.

      

    It
    was seen that the use of lactated Ringer’s solution
    for resuscitation caused a significant increase in
    cell apoptosis in the small intestine and the liver
    as compared with other agents used for
    resuscitation.

          

  • FA
    Luchette, BRH Robinson, LA Friend, et al (Univ of
    Cincinnati, Ohio)

    Adrenergic
    Antagonists Reduce Lactic Acidosis in Response to
    Hemorrhagic Shock

    J Trauma : Injury Infect Crit Care 
    46: 873-880, 1999.

        

    During
    haemorrhagic shock, lactic acidosis and plasma
    catecholamines are significantly increased. The increase in circulating catecholamines have a greater effect on
    the post haemorrhagic lactic acidosis than do poor
    perfusion and tissue hypoxia.

      

    The
    use of
    a-blockers
    with a
    b-blocker
    significantly reduces plasma lactate levels, but had
    no effect on tissue perfusion.
    In an in-vitro study propranolol eliminated
    the increased lactate production by muscle in
    response to epinephrine.

       

  • E
    Barquist, E Fein, D Shadick, et al (Univ of Miami,
    Fla)

    A
    Randomized Prospective Trial of Amphotericin B Lipid
    Emulsion Versus Dextrose Colloidal Solution in
    Critically ill
    Patients.

    J Trauma  47: 336-340, 1999.

       

    Amphotericin
    B is the drug of choice in fungal infections in
    critically ill patients.
    However, it carries at least a 50% risk of
    nephrotoxicity, inspite of preventive measures.

      

    A
    trial was conducted using a combination of
    Amphotericin B with 20% intralipid solution in
    critically ill patients with positive fungal
    cultures of peritoneum, sputum or blood.
    The dose was 1mg/kg/d as against 0.5mg/kg/d
    given to controls (with 5% dextrose).

      

    It
    was found to have less nephrotoxicity than
    Amphotericin with Dextrose.
    It can safely be given at a higher total
    cumulative dose.

         

  • RS
    Hotchkiss, PE Swanson, CM Knudson, et al (Washington
    Univ, St Louis)

    Overexpression
    of Bcl-2 in Transgenic Mice Decreases Apoptosis and
    Improves Survival in Sepsis.

    J Immunol 162: 4148-4156, 1999

       

    Sepsis is associated with extensive lymphocyte
    apoptosis, which may reduce inflammation, but
    impairs host defences.

      

    The
    effect of Bcl-2 (a protein product) has been shown
    to prevent apoptotic cell death.
    Its effect on lymphocyte 
    apoptosis was studied in a rat model
    comparing 2 sets. (1) transgenic mice that
    selectively overexpressed B cl-2 in T lymphocytes as
    well as in endotoxin 
    resistant species and (2) the endotoxin
    sensitive species.

      

    The
    Bcl-2 overexpressors showed complete protection
    against sepsis induced apoptosis.
    The protective effect may result from the
    preservation of mitochondrial membrane potential.

         

  • Heyland
    DK, for the Canadian Critical Care Trials Group
    [Queen’s Univ, Kingston, Ont, Canada; et al]


    The Clinical Utility of Invasive Diagnostic
    Techniques in the Setting of Ventilator – Associated
    Pneumonia


    Chest
    115: 1076-1084, 1999

      

    Ventricular-associated
    pneumonia [VAP] is often diagnosed on clinical
    grounds alone and contributes to the morbidity,
    mortality and costs of caring for critically ill
    patients. Overdiagnosis may be disastrous with the
    use of needless antibiotics and the delay in
    recognition of the ‘true’ diagnosis.

      

    The utility of invasive investigations like
    bronchoscopy, with protected brush catheter [PBC]
    bronchoalveolar lavage [BAL] was evaluated in 92
    patients receiving ventilatory support 
    with a clinical suspicion of VAP.

        

    The results showed that VAP was often overdiagnosed
    after BAL or PBC after these procedures. Patients
    received fewer antibiotics. Both groups had similar
    duration of mechanical ventilation and ICU stay.
    Those who underwent PBC/BAL had a lower mortality.

     

    Invasive
    diagnostic testing may boost physicians confidence
    in the diagnosis and management of VAP.

        



 

   

Speciality Spotlight

   

   
Surgery
   

 

critical care
     

  • J Briegel, H Forst, M Haller, et al (Ludwig-Maximilians-Universitat Munchen, Munich)
    Stress Doses of Hydrocortisone Reverse Hyperdynamic Septic Shock: A Prospective, Randomized, Double-blind, Single-center Study.
    Crit Care Med 27:723-732, 1999.
         
    Past studies have showed that stress doses of hydrocortisone were ineffective in septic shock. However, recent studies have shown that a patient in septic shock may have relative adrenocortical insufficiency.
        
    In septic shock, a 100mg loading dose of hydrocortisone was given within 30 min, and followed by an infusion of (0.18mg/kg/hr) hydrocortisone. After reversal of shock, the dose was reduced to 0.08mg/kg/hr and continued for 6 days.
        
    This significantly reduces the duration of vasopressor support and may shorten the time for resolution of sepsis induced organ dysfunction.
           

  • MB Malay, Jr Ashton RC, DW Landry, et al (Allegheny Gen Hosp, Pittsburgh, Pa; Columbia, Univ, New York)
    Low-Dose Vasopressin in the Treatment of Vasodilatory Septic Shock
    J Trauma  47: 699-705, 1999.
        
    Refractory hypotension not responding to epinephrine in septic shock is potentially fatal. It has been suggested that vasopressin used concomitantly could give better results.
       
    The vasopressor was infused at a rate of 0.04U/min. This permitted maintenance of arterial pressure thus allowing withdrawal of vasopressors.
          

  • MWA Angstwurm, J Schottdorf, J Schopohl, et la (Univ of Munich, Germany)
    Selenium Replacement in Patients with Severe Systemic Inflammatory Response Syndrome Improves Clinical Outcome.
    Crit Care Med 27: 1807-1813, 1999.
       
    Systemic inflammatory response syndrome (SIRS) causes substantial morbidity and mortality. It has also been recorded that selenium concentrations are reduced in SIRS. This is a pilot study on the effects of selenium replacement on SIRS related morbidity and mortality.
        
    Selenium was replaced as i.v. sodium selenite in a decreasing dosage over a period of 10 days.
         
    Within 30 days, patients had normal selenium and glutathione peroxidose levels. There was significant reduction in Acute Physiologic and Chronic Health Evaluation III scores as compared to controls. Only 14% (as against 43% in controls) had renal failure and the mortality was 34% against 54% in the control group.
         

  • JE Gadek, and the Enteral Nutrition in ARDS Study Group (Ohio State Univ, Columbus; et al )
    Effect of Enteral Feeding with Eicosapentaenoic Acid, g-Linolenic Acid, and Antioxidants in Patients with Acute Respiratory Distress Syndrome.
    Crit Care Med  27: 1409-1420, 1999.
       
    Low carbohydrate, high fat nutritional support for ventilated patients reduces demands on the respiratory system and decreases the severity of the inflammatory injury. Animal studies show that diets rich in eicosapentaenoic acid,
    g-linolenic acid and antioxidants can moderate inflammation. This is a prospective double blind randomized controlled trial (multi-centered) to evaluate the effect of a diet supplemented with EPA, GLA and antioxidants on the clinical outcome of ARDS.
       
    The patients on the test diet required fewer days of ventilatory support in ICU or on supplemental oxygen and had less new organ failure. The infection rates were the same but the test diet patients had fewer adverse events.
         

  • VM Ranieri, PM Suter, C Tortorella, et al (Univ of Toronto)
    Effect of Mechanical Ventilation on Inflammatory Mediators in Patients with Acute Respiratory Distress Syndrome: A Randomized Controlled Trial.
    JAMA 282:54-61, 1999
       
    Mechanical ventilation can escalate or cause an inflammatory response and acute lung injury. The influence of mechanical ventilation on the lung and systemic cytokine release was assessed in patients with ARDS.
      
    Two groups were assessed (1) a control group and (2) a lung protective strategy group.
      
    At baseline physiologic characteristics and cytokine concentrations were similar. But after 24 and 36 hours, there were significant between-group differences in tidal volume, end-inspiratory plateau pressures and PEEP. The lung protective strategy group had significantly better results. It could be concluded that mechanical ventilation can produce a cytokine response that may be diminished by minimising overdistension and recruitment and derecruitment of the lung.
         

  • PC Hebert, for the Canadian Critical Care Trials Group (Univ of Ottawa, Canada; et al)
    A Multicenter, Randomized, Controlled Clinical Trial of Transfusion Requirements in Critical Care,
    N Engl J Med 340: 409-417, 1999.
      
    The optimal transfusion strategy for cirtically ill anaemia patients has not been standardised. A randomised, controlled study was undertaken comparing a restrictive (when Hb <7.0gms/dL) with a liberal approach (when Hb <10gms/dL).
      
    The study was conducted on 838 critically ill patients randomly assigned to one of the two groups.
      
    The overall 30 days mortality was similar. Mortality rates were significantly lower in the restrictive group in less acutely ill patients but was similar in critically ill patients. The mortality during hospitalization was significantly lower in the restrictive group.
        

  • S Deb, B Martin, L Sun, et al (Natl Naval Med Ctr, Bethesdam Md; Walter Reed Army Med Ctr, Washington, DC; Uniformed Services Univ of the Health Sciences, Bethesda, Md)
    Resuscitation With Lactated Ringer’s Solution in Rats with Hemorrhagic Shock Induces Immediate Apoptosis.
    J Trauma: Injury Infect Crit Care  46: 582-589, 1999.
      
    For patients in haemorrhagic shock, reperfusion injury can cause cell damage, leading to cell death and organ failure. Apoptotic cell death is thought to play an important role in the pathophysiology of haemorrhagic shock. The effects of resuscitation with lactated Ringer’s solution on cell apoptosis were assessed.
      
    It was seen that the use of lactated Ringer’s solution for resuscitation caused a significant increase in cell apoptosis in the small intestine and the liver as compared with other agents used for resuscitation.
          

  • FA Luchette, BRH Robinson, LA Friend, et al (Univ of Cincinnati, Ohio)
    Adrenergic Antagonists Reduce Lactic Acidosis in Response to Hemorrhagic Shock
    J Trauma : Injury Infect Crit Care  46: 873-880, 1999.
        
    During haemorrhagic shock, lactic acidosis and plasma catecholamines are significantly increased. The increase in circulating catecholamines have a greater effect on the post haemorrhagic lactic acidosis than do poor perfusion and tissue hypoxia.
      
    The use of
    a-blockers with a b-blocker significantly reduces plasma lactate levels, but had no effect on tissue perfusion. In an in-vitro study propranolol eliminated the increased lactate production by muscle in response to epinephrine.
       

  • E Barquist, E Fein, D Shadick, et al (Univ of Miami, Fla)
    A Randomized Prospective Trial of Amphotericin B Lipid Emulsion Versus Dextrose Colloidal Solution in Critically ill Patients.
    J Trauma  47: 336-340, 1999.
       
    Amphotericin B is the drug of choice in fungal infections in critically ill patients. However, it carries at least a 50% risk of nephrotoxicity, inspite of preventive measures.
      
    A trial was conducted using a combination of Amphotericin B with 20% intralipid solution in critically ill patients with positive fungal cultures of peritoneum, sputum or blood. The dose was 1mg/kg/d as against 0.5mg/kg/d given to controls (with 5% dextrose).
      
    It was found to have less nephrotoxicity than Amphotericin with Dextrose. It can safely be given at a higher total cumulative dose.
         

  • RS Hotchkiss, PE Swanson, CM Knudson, et al (Washington Univ, St Louis)
    Overexpression of Bcl-2 in Transgenic Mice Decreases Apoptosis and Improves Survival in Sepsis.
    J Immunol 162: 4148-4156, 1999
       
    Sepsis is associated with extensive lymphocyte apoptosis, which may reduce inflammation, but impairs host defences.
      
    The effect of Bcl-2 (a protein product) has been shown to prevent apoptotic cell death. Its effect on lymphocyte  apoptosis was studied in a rat model comparing 2 sets. (1) transgenic mice that selectively overexpressed B cl-2 in T lymphocytes as well as in endotoxin  resistant species and (2) the endotoxin sensitive species.
      
    The Bcl-2 overexpressors showed complete protection against sepsis induced apoptosis. The protective effect may result from the preservation of mitochondrial membrane potential.
         

  • Heyland DK, for the Canadian Critical Care Trials Group [Queen’s Univ, Kingston, Ont, Canada; et al]
    The Clinical Utility of Invasive Diagnostic Techniques in the Setting of Ventilator – Associated Pneumonia
    Chest 115: 1076-1084, 1999
      
    Ventricular-associated pneumonia [VAP] is often diagnosed on clinical grounds alone and contributes to the morbidity, mortality and costs of caring for critically ill patients. Overdiagnosis may be disastrous with the use of needless antibiotics and the delay in recognition of the ‘true’ diagnosis.
      
    The utility of invasive investigations like bronchoscopy, with protected brush catheter [PBC] bronchoalveolar lavage [BAL] was evaluated in 92 patients receiving ventilatory support  with a clinical suspicion of VAP.
        
    The results showed that VAP was often overdiagnosed after BAL or PBC after these procedures. Patients received fewer antibiotics. Both groups had similar duration of mechanical ventilation and ICU stay. Those who underwent PBC/BAL had a lower mortality.
     
    Invasive diagnostic testing may boost physicians confidence in the diagnosis and management of VAP.
        

 

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