Use of the SOFA score to assess the incidence of organ dysfunction/failure in intensive care units: results of a multicenter, prospective study. Working group on "sepsis-related problems" of the European Society of Intensive Care Medicine

OBJECTIVE: To evaluate the use of the Sequential Organ Failure Assessment (SOFA) score in assessing the incidence and severity of organ dysfunction in critically ill patients. DESIGN: Prospective, multicenter study. SETTING: Forty intensive care units (ICUs) in 16 countries. PATIENTS: Patients admitted to the ICU in May 1995 (n = 1,449), excluding patients who underwent uncomplicated elective surgery with an ICU length of stay <48 hrs. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The main outcome measures included incidence of dysfunction/failure of different organs and the relationship of this dysfunction with outcome. In this cohort of patients, the median length of ICU stay was 5 days, and the ICU mortality rate was 22%. Multiple organ dysfunction and high SOFA scores for any individual organ were associated with increased mortality. The presence of infection on admission (28.7% of patients) was associated with higher SOFA scores for each organ. The evaluation of a subgroup of 544 patients who stayed in the ICU for at least 1 wk showed that survivors and nonsurvivors followed a different course. This subgroup had greater respiratory, cardiovascular, and neurologic scores than the other patients. In this subgroup, the total SOFA score increased in 44% of the nonsurvivors but in only 20% of the survivors (p < .001). Conversely, the total SOFA score decreased in 33% of the survivors compared with 21% of the nonsurvivors (p < .001). CONCLUSIONS: The SOFA score is a simple, but effective method to describe organ dysfunction/failure in critically ill patients. Regular, repeated scoring enables patient condition and disease development to be monitored and better understood. The SOFA score may enable comparison between patients that would benefit clinical trials.     

Usefulness of gastric intramucosal pH for monitoring hemodynamic complications in critically ill children

OBJECTIVE: To assess the efficacy of gastric intramucosal pH for the evaluation of tissue perfusion and prediction of hemodynamic complications in critically ill children. DESIGN: Open prospective study without controls. SETTING: Pediatric intensive care unit (ICU) of a tertiary care university pediatric hospital. PATIENTS: Thirty critically ill children (16 boys and 14 girls), age range: 3 months-12 years. MEASUREMENTS AND RESULTS: A tonometry catheter was placed in the stomach of all patients on admission to the pediatric ICU. Simultaneous tonometry and arterial gas measurements were made on admittance and every 6-12 h throughout the study; a total of 202 measurements were made. The catheter was removed after extubation and/or when the patient was hemodynamically stable. Intramucosal pH was calculated using the Henderson-Hasselbalch equation based on the pCO2 of the tonometer and arterial bicarbonate. Intramucosal pH values between 7.30 and 7.45 were considered to be normal. The patient's condition was analyzed using the Pediatric Risk Mortality Score (PRISM). The relations between intramucosal pH and the presence of major hemodynamic complications (cardiopulmonary arrest, shock), minor hemodynamic complications (hypotension, hypovolemia or arrhythmia), death, PRISM score and the duration of the stay in the pediatric ICU were analyzed. Intramucosal pH on admission was 7.48 +/- 0.15 on average (range 7.04-7.68). Five patients (16%) had an intramucosal pH lower than 7.30 on admission; these patients did not have a higher incidence of hemodynamic complications. The 16 patients (53%) who had an intramucosal pH of less than 7.30 at some time during the course of their disease had more hemodynamic complications than the patients who did not have pH lower than 7.30 (p < 0.0001). Every case of cardiopulmonary arrest and shock was related to intramucosal pH of less than 7.30. Patients with major complications (cardiopulmonary arrest and shock) had lower intramucosal pHs than those with minor hemodynamic complications (p = 0.03); similarly, they had low intramucosal pH readings more often than those with minor complications (p = 0.0032). Intramucosal pH values less than 7.30 had a sensitivity of 90% and a specificity of 98% as a predictor of hemodynamic complications. There was no relation between intramucosal pH lower than 7.30 and either PRISM or the duration of the stay in the pediatric ICU. Patients with intramucosal pH less than 7.20 had a higher PRISM than the patients who did not have pH lower than 7.20 (p < 0.05). A patient who died during the study due to cardiopulmonary arrest had prior intramucosal pH measurements of 7.23 and 7.10, and three patients died of late complications after the end of the study. Hemodynamic complications were not detected with arterial pH. Gap pH (arterial pH-intramucosal pH) and standard pH measurements yielded the same results as gastric intramucosal pH. CONCLUSION: Intramucosal pH could provide a useful early indication of hemodynamic complications in critically ill children.     

A new dimension of the PACU: the dilemma of the ICU overflow patient

With the increase in the number of critically ill patients needing extended periods of time in the ICU and the subsequent shortage of ICU beds, hospitals have examined ways to use the PACU as an alternative for the short-term critically ill patient. This article identifies common problems encountered by the PACU staff, and the author suggests criteria for establishing and implementing guidelines for successful integration of these short-term critically ill patients without losing sight of the PACU's goals and compromising patient care. The criteria for establishing guidelines were based on the personal experience of the author in developing a program for ICU overflow patients, as well as from experiences of other PACU nurses working in PACUs where successful guidelines currently are used.     

Mitchell osteotomy for adolescent hallux valgus

BACKGROUND: Complications often follow if a choledochal cyst is treated simply by drainage, either internal or external. This study reviews 17 patients who had had previous cystoenterostomy (n = 9) or external drainage (n = 8) and who required reoperation and cyst excision. METHODS: The study was a retrospective review including ten women and seven men managed over 9 years. The indications for reoperation were stone formation (10 patients), pancreatitis (three), portal hypertension (two) and hepatic abscess (one); two patients were asymptomatic. RESULTS: Definitive surgery with cyst excision was possible in all patients who had previously had external cyst drainage and in seven of nine who had had previous cystoenterostomy. There were no deaths. Two postoperative biliary leaks and two duodenal fistulas resolved spontaneously. CONCLUSION: Excision of a choledochal cyst is possible and desirable even after a previous drainage operation. In severely ill patients with a complication of choledochal cyst, external drainage may be a preferable initial manoeuvre.     

Atrial natriuretic factor modifies the biosynthesis and turnover of norepinephrine in the rat adrenal medulla

Abnormalities of the cornea and conjunctiva occur in association with neurological diseases, nocturnal lagophthalmos, coma, infection, and mechanical ventilation. We investigated the incidence and causes of ocular surface disorders in critically ill patients. In a retrospective study, the presence of conjunctivitis and corneal erosion was determined by reviewing the medical charts of 143 mechanically ventilated patients (intensive care unit [ICU] stay > or =7 days). In the subsequent prospective study, 15 patients who had sedatives or muscle relaxants administered continuously for more than 48 h in the ICU were investigated. Corneal erosion was examined using a slit lamp once a day. Ocular surface disorder was found in 28 of the 143 patients (20%) whose ICU stay exceeded 7 days. The incidence increased with continuous sedation (35% vs 15%). The incidence also increased with continuous neuromuscular blockade (39% vs 11%). In the prospective study, nine patients (60%) developed corneal erosion. A patient's inability to fully close his or her eyes increased the incidence (P < 0.01) of corneal erosion. Protective eyelid taping was effective in preventing and treating the corneal erosion. In conclusion, the critically ill often develop ocular surface disorders, especially when sedated and immobilized. A close relationship was observed between these conditions and the inability to close one's eyes.     

Neurological intensive care admissions: identifying candidates for intermediate care and the services they receive

OBJECTIVE: The high cost and scarcity of intensive care unit (ICU) beds has resulted in a need for improved utilization. This study describes the characteristics of patients who are admitted to the ICU for neurosurgical and neurological care, identifies patients who might receive all or most of their care in an intermediate care unit, and describes the services the patients would receive in an intermediate care unit. METHODS: We describe patients who received neurological care and who were part of a prospective study of 17,440 patients admitted to 42 ICUs at 40 United States hospitals. We identified patients who received only monitoring during ICU Day 1 and then used a previously validated equation to distinguish which patients were at low risk (< 10%) for subsequent active life-supporting therapy. We also describe the services these patients received during their ICU stay. RESULTS: Among 3000 patients admitted to the ICU for neurological care, 1350 received active therapy and 1650 (55%) underwent monitoring and received concentrated nursing care on ICU Day 1. After excluding those patients who received active therapy at admission, 1288 (78%) of the 1650 patients who underwent monitoring at admission were at low risk (< 10%) for subsequent active therapy; 95.8% received no active therapy. These patients who were at low risk for subsequent active therapy were significantly (P < 0.001) more often admitted postoperatively, were younger and less severely ill, and had lower ICU and hospital mortality rates (0.9 and 3.9%, respectively) than patients who received active treatment at admission. CONCLUSIONS: Patients receiving neurological care at an ICU who receive only monitoring during their 1st ICU day and have a less than 10% predicted risk of active treatment can be safely transferred to an intermediate care unit. Some of these patients may not require ICU admission. We suggest guidelines for equipping and staffing neurological intermediate care units based on the type and amount of therapy received by these patients.     

Randomized clinical outcome study of critically ill patients given glutamine-supplemented enteral nutrition

Glutamine is normally an abundant amino acid in the body. It has many important metabolic roles, which may protect or promote tissue integrity and enhance the immune system. Low plasma and tissue levels of glutamine in the critically ill suggest that demand may exceed endogenous supply. A relative deficiency of glutamine could compromise recovery, resulting in prolonged illness and an increase in late mortality, morbidity, and consequently hospital costs. Using a prospective block-randomized, double-blind treatment study design, we tested whether a glutamine-containing enteral feed compared with an isonitrogenous, isoenergetic control feed would influence outcome. The study endpoints were morbidity, mortality, and hospital cost at 6 mo postintervention. In one general intensive care unit (ICU), to ensure consistency of management policies, 78 critically ill adult patients with Acute Physiological and Chronic Health Evaluation (APACHE) II score of 11 and greater and who were considered able to tolerate introduction of enteral nutrition were studied. Fifty patients successfully received enteral nutrition (26 glutamine, 24 control). There was no mortality difference between those patients receiving glutamine-containing enteral feed and the controls. However, there was a significant reduction in the median postintervention ICU and hospital patient costs in the glutamine recipients $23,000 versus $30,900 in the control patients (P = 0.036). For patients given glutamine there was a reduced cost per survivor of 30%. We conclude that in critically ill ICU patients enteral feeds containing glutamine have significant hospital cost benefits.     

Echo-guided percutaneous cholecystostomy in the treatment of acute cholecystitis. Apropos of 41 cases

Differents studies note many complications of the traditional cholecystectomy for acute cholecystitis in critically ill and very old patients. We report a retrospective study of ultrasound-guided cholecystostomy as an alternative treatment avoiding surgery in 41 patients between April 1988 and January 1994. Mean-age was 77.8 years (42-95). Hospital mortality concerned five (12.2%) patients. Four (9.8%) required surgical procedure, all of them with simple post-operative course. Six (14.6%) had a recurrence between 1 and 67 months after the end of the drainage. Twenty-six patients are considered as healed, without recurrence, after a mean-follow-up of 33 months. The percutaneous echoguided cholecystostomy seems to be a treatment of choice for patients with a contraindication for a surgical procedure. This technic allows an efficient treatment in patients with post-operative cholecystitis.     

Low lipid concentrations in critical illness: implications for preventing and treating endotoxemia

OBJECTIVES: To determine the prevalence and clinical significance of hypolipidemia found in critically ill patients, and whether the addition of a reconstituted lipoprotein preparation could inhibit the generation of tumor necrosis factor-alpha (TNF-alpha) in acute-phase blood taken from these patients. SETTING: Surgical intensive care unit (ICU) of a large urban university hospital. DESIGN: Prospective case series. PATIENTS: A total of 32 patients with a variety of critical illnesses had lipid and lipoprotein concentrations determined. Six patients and six age- and gender-matched control subjects had whole blood in vitro studies of the effect of lipoprotein on lipopolysaccharide mediated TNF-alpha production. INTERVENTIONS: Blood samples were drawn on admission to the ICU and over a subsequent 8-day period. MEASUREMENTS AND MAIN RESULTS: Mean serum lipid and lipoprotein values obtained from patients within 24 hrs of transfer to the surgical ICU were extremely low: mean total cholesterol was 117 mg/dL (3.03 mmol/L), low-density lipoprotein cholesterol 71 mg/dL (1.84 mmol/L), and high-density lipoprotein cholesterol 25 mg/dL (0.65 mmol/L). Only the mean triglyceride concentration of 105 mg/dL (1.19 mmol/L), and the mean lipoprotein(a) concentration of 25 mg/dL (0.25 g/L) were within the normal range. During the first 8 days following surgical ICU admission, there were trends toward increasing lipid and lipoprotein concentrations that were significant for triglycerides and apolipoprotein B. Survival did not correlate with the lipid or lipoprotein concentrations, but patients with infections had significantly lower (p = .008) high-density lipoprotein cholesterol concentrations compared with noninfected patients. Lipopolysaccharide-stimulated production of TNF-alpha in patient and control blood samples was completely suppressed by the addition of 2 mg/mL of a reconstituted high-density lipoprotein preparation. CONCLUSIONS: Patients who are critically ill from a variety of causes have extremely low cholesterol and lipoprotein concentrations. Correction of the hypolipidemia by a reconstituted high-density lipoprotein preparation offers a new strategy for the prevention and treatment of endotoxemia.     

Acute cholecystitis in the intensive care unit

The development of acute cholecystitis in the ICU is now a well-recognized complication of many acute illnesses that precipitate ICU admission and may also result as a complication of the subsequent treatment. The etiology of the disease remains obscure and, unlike acute cholecystitis outside the ICU setting, most cases are acalculous and not associated with gallstones. The disease may often go unrecognized due to the complexity of the patient's medical and surgical problems. Clinical examination is often unhelpful, as many patients are receiving mechanical ventilation and have decreased mental awareness. Biochemical markers are nonspecific and contribute to the delay in diagnosis and treatment. Early diagnosis is essential to avoid the high rates of associated morbidity and mortality. The diagnosis is usually made by radiologic tests, most often by sonographic examination of the gallbladder, which can be performed at the bedside. However, radiologic findings may also be nonspecific. The treatment involves gallbladder drainage by percutaneous cholecystostomy, which is usually curative in acalculous cholecystitis. Interval cholecystectomy is indicated for the remaining patients with gallstone-associated cholecystitis.     

Nonconvulsive status epilepticus in the critically ill elderly

PURPOSE: To describe the electrographic and clinical features of nonconvulsive status epilepticus (NCSE) in the critically ill elderly and to identify potential predictors of outcome. METHODS: We prospectively identified 25 episodes of altered mentation and NCSE in 24 critically ill elderly patients associated with generalized, focal, or bihemispheric epileptiform EEG patterns. Patients with anoxic encephalopathy were excluded. RESULTS: Of 25 hospitalizations, 13 (52%) resulted in death, and 12 (48%) patients survived to discharge. Death was associated with the number of acute, life-threatening medical problems on presentation (survivors, 1.8; fatalities, 2.8; p = 0.013) and with generalized EEG pattern (p = 0.017). Higher doses or greater number of antiepileptic drugs (AEDs) did not improve outcome. Treatment with intravenous benzodiazepines was associated with increased risk of death (p = 0.033). Ten patients with advance directives were managed outside the intensive care unit (ICU). Mean hospitalization was 39 days in the ICU group and 22 for those with advance directives (p = 0.017). CONCLUSIONS: Severity of illness correlates with mortality in critically ill elderly patients with NCSE. Treatment with intravenous benzodiazepines may increase their risk of death. Aggressive ICU management may prolong hospitalization at considerable cost, without improving outcome. It is unclear whether NCSE affects outcome in the critically ill elderly or is merely a marker for severity of disease in predisposed patients. The benefits of aggressive therapy are unclear. Carefully controlled, prospective trials will be necessary to determine the best therapies for NCSE in the critically ill elderly and the appropriate role of the ICU in their management.     

Catheter-directed thrombolysis in the treatment of phlegmasia cerulea dolens

The objective of this study was to review the incidence, risk factors, methods of diagnosis, and outcome of acute acalculous cholecystitis (AAC) and to identify the sensitivity and limitations of current radiographic modalities used to establish the diagnosis. Our study was a retrospective chart review in a tertiary-care university hospital. Over a 53-month period, 27 cases of AAC (17 males, 10 females; mean age 50 years; mean Acute Physiology and Chronic Health Evaluation II score, 17) were encountered. Of these, 14 (52%) occurred in critically ill patients and 17 (63%) in patients recovering from non-biliary tract operations. AAC occurred in 0.19 per cent of surgical intensive care unit admissions and accounted for 14 per cent (27 of 188) of all cases of acute cholecystitis. Presenting symptoms and laboratory values were nonspecific. Twenty patients had radiographic studies before surgery. Among the various radiological studies used for AAC, morphine cholescintigraphy had the highest sensitivity (9 of 10; 90%), followed by computed tomography (8 of 12; 67%) and ultrasonography (2 of 7; 29%). Ten of the 20 patients had more than one study done preoperatively. All 27 patients had an open cholecystectomy. AAC was associated with a high incidence of gangrene (17 of 27 cases; 63%), perforation (4 of 27; 15%), and abscess (1 of 27; 4%). The mortality rate was 41 per cent (11 of 27). We conclude that AAC is a rare, but potentially lethal, disease occurring in critically ill patients and those recovering from non-biliary tract operations. The clinical presentation is nonspecific, and significant delays in diagnosis result in a high incidence of gangrene, perforation, abscess, and death. To improve outcome, a high index of suspicion with early radiographic evaluation, often employing multiple studies, is necessary. An algorithm for the evaluation of patients for suspected AAC is proposed.     

Wortmannin-sensitive activation of p70S6-kinase and MAP-kinase by the G protein-coupled receptor, G/CCKB

OBJECTIVE: To determine whether emergency rigid bronchoscopic intervention, including Nd-YAG laser resection or stenting, immediately affected the need for continued mechanical ventilation or intensive care level of support in critically ill patients with acute respiratory failure from malignant or benign central airways obstruction. DESIGN: Retrospective review of medical records of all patients with acute respiratory failure and malignant or benign tracheobronchial obstruction necessitating intubation, mechanical ventilation, or hospitalization in the ICU prior to referral for therapeutic bronchoscopy. SETTING: University of California San Diego, a tertiary care institution specialized in airway management. PATIENTS: Medical records of 32 patients with malignant or benign central airways obstruction requiring admission to the ICU prior to rigid bronchoscopic intervention between January 1994 and April 1996. INTERVENTIONS: Emergent rigid bronchoscopy with dilatation, Nd-YAG laser resection, or silicone stent insertion performed in the operating room under general anesthesia. RESULTS: Thirty-two patients with central airways obstruction requiring emergent hospitalization in the ICU were referred for therapeutic rigid bronchoscopy. Airway strictures were caused by benign disease in 18 patients, and by primary bronchogenic lung cancer in 14. Of the 19 patients who were mechanically ventilated, bronchoscopic intervention allowed immediate discontinuation of mechanical ventilation in 10 (52.6%). Twenty-five patients had indwelling artificial airways (12 endotracheal tubes, 13 tracheotomy tubes). Two, however, were considered tracheotomy-dependent because of neuromuscular disease. Of the remaining 23 patients, immediate extubation or decannulation was possible in seven (30.4%). Of seven patients with no indwelling airway, five (71.4%) were immediately transferred to a lower level of care after intervention. Of the 32 total patients, 20 (62.5%) were immediately transferred to a lower level of care immediately after intervention. CONCLUSIONS: Emergency laser resection or stent insertion can favorably affect health-care utilization in patients with acute respiratory distress from central airways obstruction. Treatment may be lifesaving and allows successful withdrawal from mechanical ventilation, hospitalization in a lower level of care environment, relief of symptoms, and extended survival in critically ill patients. In patients with regionally advanced cancer, the palliative nature of this procedure postpones death by respiratory distress and may prompt consideration for institution of conservative comfort measures to reduce patient suffering.     

Use of 2% propofol to produce diurnal sedation in critically ill patients

OBJECTIVE: The assessment of propofol to produce diurnal sedation in critically ill patients. DESIGN: Prospective clinical study. SETTING: Intensive Care Unit, University Hospital. PATIENTS AND PARTICIPANTS: Thirty consecutive patients admitted to the Intensive Care Unit older than 18 years who were expected to be sedated for more than 50 h. INTERVENTIONS: The patients were randomised into two groups. All received sedation with a constant background infusion of morphine and a variable infusion rate of propofol, which was altered hourly to maintain the intended sedation score. The first group received constant light sedation (CLS) over 50 h aiming for a Ramsay score of 2-3. The second group received CLS between 0600 h and 2200 h and additional night sedation (ANS) with propofol between 2200 h and 0600 h, aiming for a sedation score of 4-5. MEASUREMENTS AND RESULTS: Patients were studied for 50 h from 1800 h on the first day of admission. Recordings of heart rate, blood pressure, sedation scores and propofol and morphine infusion rates were made hourly. An APACHE II score was recorded for each patient. Sedation scores were analysed by blind visual assessment and cosinor analysis, which is used in chronobiology to examine the correlation of data with a cosine curve. Patients in the ANS group had significantly better rhythmicity of sedation levels using cosinor analysis (r = 26% v 8%) p < 0.01. There was no difference between the CLS and ANS groups with respect to age, sex or APACHE II scores. Nine out of 15 patients in the ANS group achieved diurnal sedation. Three patients in the CLS group showed diurnal rhythmicity of sedation, which can be attributed to natural sleep, and had a median APACHE II score of 12. Five patients in the CLS group and three in the ANS group showed a deep constant sedation pattern. They had high APACHE II scores (median 21.5) and an obtunded conscious level on admission due to severe sepsis. CONCLUSION: Propofol can safely provide diurnal sedation in the critically ill when titrated against the Ramsay score. Sedation levels cannot be manipulated in some severely ill patients.     

Trace element and vitamin concentrations and losses in critically ill patients treated with continuous venovenous hemofiltration

OBJECTIVES: To measure the blood concentrations of a number of trace elements and vitamins in critically ill patients and examine their elimination by continuous venovenous hemofiltration (CVVH). SETTING: Intensive care unit of a tertiary institution. DESIGN: Prospective, controlled, clinical study. PATIENTS: Eight critically ill patients requiring renal replacement therapy, nine patients requiring intensive care treatment but not requiring renal replacement therapy, and nine healthy controls. INTERVENTIONS: Measurement of trace element and vitamin concentrations in blood and ultrafiltrate. MEASUREMENTS AND MAIN RESULTS: Compared with normal volunteers, critically ill patients requiring CVVH had significantly lower median blood concentrations of vitamin C, vitamin E, selenium, and zinc. During the first 24 hrs of CVVH, there were no changes in the trace element and vitamin concentrations in blood, nor were there differences between pre- and postfilter samples. Micronutrient losses in the ultrafiltrate were small or undetectable except for Vitamin C, chromium, and copper. Compared with normal volunteers, critically ill patients not requiring CVVH also had significantly lower median blood concentrations of vitamin C, vitamin E, selenium, and zinc. There were no differences between the two critically ill groups. CONCLUSIONS: The clinical significance of the reductions in blood concentrations of selenium, zinc, vitamin C, and vitamin E in critically ill patients and the ultrafiltrate losses of Vitamin C, copper, and chromium remains unclear.     

Epidemiology of sepsis and multiple organ dysfunction syndrome in children

STUDY OBJECTIVES: To determine the cumulated incidence and the density of incidence of systemic inflammatory response syndrome (SIRS), sepsis, severe sepsis, septic shock, and multiple organ dysfunction syndrome (MODS) in critically ill children; to distinguish patients with primary from those with secondary MODS. DESIGN: Prospective cohort study. SETTING: Pediatric ICU of a university hospital. PATIENTS: One thousand fifty-eight consecutive hospital admissions. INTERVENTIONS: None. MEASUREMENTS AND RESULTS: SIRS occurred in 82% (n=869) of hospital admissions, 23% (n=245) had sepsis, 4% (n=46) had severe sepsis, 2% (n=25) had septic shock; 16% (n=168) had primary MODS and 2% (n=23) had secondary MODS; 6% (n=68) of the study population died. The pediatric risk of mortality (PRISM) scores on the first day of admission to pediatric ICU were as follows: 3.9 +/- 3.6 (no SIRS), 7.0 +/- 7.0 (SIRS), 9.5 +/- 8.3 (sepsis), 8.8 +/- 7.8 (severe sepsis), 21.8 +/- 15.8 (septic shock); differences among groups (p=0.0001), all orthogonal comparisons, were significant (p<0.05), except for patients with severe sepsis. The observed mortality for the whole study population was also different according to the underlying diagnostic category (p=0.0001; p<0.05 for patients with SIRS and those with septic shock, compared with all groups). Among, patients with MODS, the difference in mortality between groups did not reach significance (p=0.057). Children with secondary MODS had a longer duration of organ dysfunction (p<0.0001), a longer stay in pediatric ICU after MODS diagnosis (p<0.0001), and a higher risk of mortality (odds ratio, 6.5 [2.7 to 15.9], p<0.0001) than patients with primary MODS. CONCLUSIONS: SIRS and sepsis occur frequently in critically ill children. The presence of SIRS, sepsis, or septic shock is associated with a distinct risk of mortality among critically ill children admitted to the pediatric ICU; more data are needed concerning children with MODS. Secondary MODS is much less common than primary MODS, but it is associated with an increased morbidity and mortality; we speculate that distinct pathophysiologic mechanisms are involved in these two conditions.     

Elevated methemoglobin in patients with sepsis

BACKGROUND: It has been reported that large amounts of nitric oxide (NO) are released in patients with sepsis. NO is converted to methemoglobin and nitrate. This study was designed to determine whether blood methemoglobin levels were increased in patients with sepsis or septic shock. METHODS: Forty-five critically ill patients including 8 with sepsis but without shock, 6 with septic shock and 31 non-septic patients were enrolled in the study. For septic and septic shock patients, blood methemoglobin concentrations were measured during sepsis or septic shock and at the time of recovery or just before the onset of sepsis. For the remaining non-septic patients, methemoglobin concentrations were measured at ICU admission and discharge. RESULTS: Blood methemoglobin levels in the presence of sepsis or septic shock were significantly (P < 0.05) higher than those in non-septic patients and those at recovery or just before the onset of sepsis in both septic and septic shock patients. CONCLUSIONS: Blood methemoglobin concentration may be useful as a marker of the onset of sepsis or septic shock.     

Impaired gastric emptying in mechanically ventilated, critically ill patients

OBJECTIVE: To measure gastric emptying in critically ill patients using an acetaminophen absorption model and determine which variables are associated with impaired gastric emptying. DESIGN: A prospective, cohort study. SETTING: A medical/surgical ICU at a tertiary care hospital: Hamilton General Hospital, Hamilton, Ontario. PATIENTS AND PARTICIPANTS: We recruited 72 mechanically ventilated patients expected to remain in the ICU for more than 48 h. Our results were compared to those in healthy volunteers. INTERVENTION: Within 48 h of admission to the ICU, 1.6 g acetaminophen suspension were administered via a nasogastric tube into the stomach. Blood samples were drawn a t = 0, 30, 60, 90, and 120 min for measurement of plasma acetaminophen levels determined by the enzymatic degradation method. MEASUREMENTS AND RESULTS: Maximal concentration of acetaminophen was 94.1 (75.3) mumol/l compared to 208.4 (33.1) mumol/l in a control population (p < 0.0001). The time to reach the maximal concentration was 105 min (60-180) compared to 30 min (15-90) in controls (p < 0.0001). The area under the time-acetaminophen concentration curve t = 120 was 9301 (7343) mumol/min per l compared to 11644 (1336) mumol/min per l in the controls (p = 0.28). The variables associated with delayed gastric emptying were age, sex and use of opioids for analgesia and sedation. CONCLUSIONS: Gastric emptying is delayed in critically ill patients. The important consequences of this phenomenon include intolerance to enteral nutrition and gastric colonization. Strategies to minimize the use of narcotics may improve gastric emptying. Studies to examine the effect of gastrointestinal prokinetic agents on gastric emptying are needed.     

A natural experiment on the effects of ovarian hormones on cardiovascular risk factors and stress reactivity: bilateral salpingo oophorectomy versus hysterectomy only

Indirect calorimetry is the method by which metabolic rate and substrate utilization are estimated in human beings starting from respiratory gas exchange measurements and urinary nitrogen excretion. This method is based on some models and assumptions that must be known and taken into consideration to correctly interpret the results obtained. Recent advances in technology and the availability of precise and portable metabolic carts have made this technique practical at the beside even in critically ill patients. It must be considered that, particularly in the ICU, there may be several sources of error and many technical difficulties in applying this methodology. Taking into account the relevant clinical studies related to the outcomes of critically ill patient, this article defines when the assessment of energy expenditure by indirect calorimetry may provide useful and valid information. Review of the literature suggests that the clinical application of indirect calorimetry in critically ill patients, although promising, requires further evaluation. Currently, the potential useful clinical applications of indirect calorimetry in this category of patients can be summarized as follows: (1) assessment of energy expenditure in patients who fail to adequately respond to the estimated nutritional needs; (2) assessment of energy expenditure in patients with single- or multiple-organ dysfunction who need prolonged ICU care and artificial nutritional support; (3) assessment of the effects induced by artificial nutrition on the cardiocirculatory and respiratory systems in mechanically ventilated patients with acute respiratory failure; and (4) monitoring of VO2 during weaning from mechanical ventilation.