Jeffrey A. Claridge

The golden hour and the silver day : Detection and correction of occult hypoperfusion within 24 hours improves outcome from major trauma

BACKGROUND The significance of occult hypoperfusion (OH) in the development of respiratory complications (RC), multiple system organ failure (MSOF), and death, and the effect of rapid identification and correction of OH in the severely injured trauma patient was investigated. METHODS A pilot retrospective study and the analysis of a prospective protocol to correct OH were performed. Pilot study: all trauma patients admitted to our Level I trauma center between February and December of 1995, who survived greater than 48 hours, had an Injury Severity Score greater than or equal to 20, and intensive care unit stays greater than 48 hours were evaluated. Prospective study: patients admitted between January 1, 1996, and April 30, 1997, who survived greater than 24 hours, with Injury Severity Score greater than or equal to 20, and who were hemodynamically stable (systolic blood pressure greater than 100, pulse rate less than 120, and urine output greater than 1 mL/kg per hour) were included. Serum lactic acid (LA) levels were measured at arrival and at proscribed intervals. In the pilot study, initial LA levels were examined in relation to outcome and complications. In the prospective study, patients with two consecutive LA levels greater than 2.5 mmol/L underwent invasive monitoring and vigorous resuscitation to correct their lactic acidosis. RESULTS Among the 31 patients studied in the pilot study, there were 4 deaths, 6 cases of MSOF, and 13 patients with RC. Lactic acidosis and poor cardiac performance, as evidenced by low cardiac index (CI) with normal filling pressures, were seen in all cases of MSOF and RC, as well as in all deaths. From these results, the prospective study was performed. Eighty-five intensive care unit patients met criteria for inclusion in the study. Six additional patients were excluded because of severe, untreatable intracranial hypertension at admission to the intensive care unit. Fifty-eight of these patients had OH in the first 24 hours. Forty-four patients corrected their OH within 24 hours with vigorous resuscitation. There were no deaths, three cases of MSOF, and 10 cases of RC in those patients who corrected OH within 24 hours. Persistent OH (>24 hours) was seen in 14 patients, despite resuscitative efforts, 43% of whom died. MSOF and RC were present in 36% and 50% of cases, respectively (p<0.05). CONCLUSION Initial lactic acidosis is associated with lower cardiac performance and higher morbidity and mortality. Persistent OH is associated with higher rates of RC, MSOF, and death after severe trauma. Early identification and aggressive resuscitation aimed at correcting continued elevation in serum lactate improves survival and reduces complications in severely injured trauma patients.

Persistent occult hypoperfusion is associated with a significant increase in infection rate and mortality in major trauma patients.

OBJECTIVE To investigate the hypothesis that occult hypoperfusion (OH) is associated with infectious episodes in major trauma patients. METHODS Data were collected prospectively on all adult trauma patients admitted to the Surgical/Trauma Intensive Care Unit from November of 1996 to December of 1998. Treatment was managed by a single physician according to a defined resuscitation protocol directed at correcting OH (lactic acid [LA] > 2.4 mmol/L). RESULTS Of a total of 381 consecutive patients, 118 never developed OH and 263 patients exhibited OH. Seventeen patients were excluded because their LA never corrected, and they all subsequently died. One hundred seventy-six infectious episodes occurred in 97 of the 364 patients remaining. The infection rate in patients with no elevation of LA was 13.6% (n = 118) compared with 12.7% (n = 110) in patients whose LA corrected by 12 hours, 40.5% (n = 79; p < 0.01 compared with all other groups) in patients whose LA corrected between 12 and 24 hours, and 65.9% (n = 57; p < 0.01 compared with all other groups) in patients who corrected after 24 hours. Among the patients with infections, there were 276 infection sites with 42% of infections involving the lung and 21% involving bacteremia. There was no difference in proportion of infections occurring at each site between groups. The mortality rate of patients who developed infections was 7.9% versus 1.9% in patients without infections (p < 0.05). Of the patients who developed infections, 69.8% versus 25.8% (p < 0.001) did not have their lactate levels normalized within 12 hours of emergency room admission. Logistic regression demonstrated that both the Injury Severity Score and OH > 12 hours were independently predictive of infection. CONCLUSION A clear increase in infections occurred in patients with OH whose lactate levels did not correct by 12 hours, with an associated increase in length of stay, days in surgical/trauma intensive care unit, hospital charges, and mortality.

Trial of Short-Course Antimicrobial Therapy for Intraabdominal Infection

BACKGROUND The successful treatment of intraabdominal infection requires a combination of anatomical source control and antibiotics. The appropriate duration of antimicrobial therapy remains unclear. METHODS We randomly assigned 518 patients with complicated intraabdominal infection and adequate source control to receive antibiotics until 2 days after the resolution of fever, leukocytosis, and ileus, with a maximum of 10 days of therapy (control group), or to receive a fixed course of antibiotics (experimental group) for 4±1 calendar days. The primary outcome was a composite of surgical-site infection, recurrent intraabdominal infection, or death within 30 days after the index source-control procedure, according to treatment group. Secondary outcomes included the duration of therapy and rates of subsequent infections. RESULTS Surgical-site infection, recurrent intraabdominal infection, or death occurred in 56 of 257 patients in the experimental group (21.8%), as compared with 58 of 260 patients in the control group (22.3%) (absolute difference, -0.5 percentage point; 95% confidence interval [CI], -7.0 to 8.0; P=0.92). The median duration of antibiotic therapy was 4.0 days (interquartile range, 4.0 to 5.0) in the experimental group, as compared with 8.0 days (interquartile range, 5.0 to 10.0) in the control group (absolute difference, -4.0 days; 95% CI, -4.7 to -3.3; P<0.001). No significant between-group differences were found in the individual rates of the components of the primary outcome or in other secondary outcomes. CONCLUSIONS In patients with intraabdominal infections who had undergone an adequate source-control procedure, the outcomes after fixed-duration antibiotic therapy (approximately 4 days) were similar to those after a longer course of antibiotics (approximately 8 days) that extended until after the resolution of physiological abnormalities. (Funded by the National Institutes of Health; STOP-IT ClinicalTrials.gov number, NCT00657566.).

History and Development of Evidence-based Medicine

This article illustrates the timeline of the development of evidence-based medicine (EBM). The term “evidence-based medicine” is relatively new. In fact, as far as we can tell, investigators from McMaster’s University began using the term during the 1990s. EBM was defined as “a systemic approach to analyze published research as the basis of clinical decision making.” Then in 1996, the term was more formally defined by Sacket et al., who stated that EBM was “the conscientious and judicious use of current best evidence from clinical care research in the management of individual patients.” Ancient era EBM consists of ancient historical or anecdotal accounts of what may be loosely termed EBM. This was followed by the development of the renaissance era of EBM, which began roughly during the seventeenth century. During this era personal journals were kept and textbooks began to become more prominent. This was followed by the 1900s, during an era we term the transitional era of EBM (1900–1970s). Knowledge during this era could be shared more easily in textbooks and eventually peer-reviewed journals. Finally, during the 1970s we enter the modern era of EBM. Technology has had a large role in the advancement of EBM. Computers and database software have allowed compilation of large amounts of data. The Index Medicus has become a medical dinosaur of the past that students of today likely do not recognize. The Internet has also allowed incredible access to masses of data and information. However, we must be careful with an overabundance of “unfiltered” data. As history, as clearly shown us, evidence and data do not immediately translate into evidence based practice.

Transfusions result in pulmonary morbidity and death after a moderate degree of injury.

BACKGROUND Prior studies have suggested that blood transfusion (Tx) is associated with infectious and respiratory complications in trauma patients. However, these studies are difficult to interpret because of small sample size, inclusion of severely injured patients in traumatic shock, and combination of a variety of unrelated low-morbidity/mortality infections, such as wound, catheter-related, and urinary tract infection as outcomes. To eliminate these confounding variables, this study evaluates the association between delayed Tx and serious, well-defined respiratory complications (ventilator-associated pneumonia [VAP] and acute respiratory distress syndrome [ARDS]) and death in a cohort of intensive care unit (ICU) admissions with less severe (Injury Severity Score [ISS] < 25) blunt trauma who received no Tx within the initial 48 hours after admission. METHODS Patients with blunt injury and ISS < 25 admitted to the ICU over a 7-year period were identified from the registry and excluded if within 48 hours from admission they received any Tx or if they died. VAP required quantitative bronchoalveolar lavage culture (> or =10(5) colonies/mL), and ARDS required Pao2/Fio2 ratio < 200 mm Hg, *** no congestive heart failure, diffuse bilateral infiltrates, and peak airway pressure > 50 cm H2O for diagnosis. Outcomes were VAP, ARDS, and death. RESULTS Nine thousand one hundred twenty-six with blunt injury were ICU admissions, and 5,260 (58%) met study criteria (72% male). Means for age, ISS, and Glasgow Coma Scale score were 39, 12, and 14, respectively. There were 778 (15%) who received delayed Tx. Incidences of VAP, ARDS, and death were 5%, 1%, and 1%, respectively. Logistic regression analysis identified age, base excess, chest Abbreviated Injury Scale score, ISS, and any transfusion as significant predictors for VAP; chest Abbreviated Injury Scale score and transfusion as significant predictors for ARDS; and age and transfusion as significant predictors for death. CONCLUSION Delayed transfusion is independently associated with VAP, ARDS, and death in trauma patients regardless of injury severity. These data mandate a judicious transfusion policy after resuscitation and emphasize the need for safe and effective blood substitutes and transfusion alternatives.

Occult hypoperfusion is associated with increased morbidity in patients undergoing early femur fracture fixation

BACKGROUND The presence of persistent occult hypoperfusion (OH) is associated with higher morbidity and mortality rates after trauma. Early femur fracture fixation in trauma patients with multiple injuries is associated with decreased morbidity and mortality. Association of OH and incidence of postoperative complications after intramedullary (IM) fixation in patients with femur fractures was investigated. METHODS A retrospective study design was used. All patients with femur fractures admitted to the trauma service of a Level I trauma center between January 1, 1995, and August 1, 1998, who were older than 18 years of age and who had IM fracture fixation within 24 hours of admission and serum lactate determinations on admission and at proscribed intervals, were included in the study. Patients with lactic acid levels > or = 2.5 mmol/L were determined to have OH. No patients had clinical signs of shock (hypotension, tachycardia, decreased urine output) on transfer to the operating room. Complete resuscitation was defined as a lactic acid level < 2.5 mmol/L. Patients were divided into two groups based on presence/absence of OH determined from the lactic acid level immediately before surgery. The incidence of all postoperative organ complications was recorded, and complication rates were compared between groups. Total hospital costs were also compared. RESULTS One hundred seventy-seven patients with femur fractures were admitted to the trauma service during this period. Seventy-nine patients met initial criteria for inclusion in the study. Further review excluded 32 patients. Occult hypoperfusion was present in 20 patients before early IM fixation (group 2). Twenty-seven patients were completely resuscitated before early IM fixation (group 1). Injury Severity Scores were similar in both groups. Group 2 had 35 complications in 20 patients, and group 1 had 11 complications in 27 patients. A significant difference was found in incidence of postoperative complications in group 1 (20%) versus group 2 (50%). Group 2 also had a significantly higher proportion of postoperative infections than group 1 (72% vs. 28%, respectively) and higher total hospital costs (

Does the addition of glutamine to enteral feeds affect patient mortality

46,469 vs.

The Effects of Splenic Artery Embolization on Nonoperative Management of Blunt Splenic Injury: A 16-year Experience

23,139). CONCLUSION The presence of OH in trauma patients undergoing early IM fixation of a femur fracture is associated with a twofold higher incidence of postoperative complications. Clinical judgment, not surgical dogma, should guide the timing of IM fixation in these patients. Identifying and correcting OH through relatively simple resuscitative measures may be advantageous in reducing morbidity in the patient with multiple injuries.

Independent Predictors of Enteric Fistula and Abdominal Sepsis After Damage Control Laparotomy: Results From the Prospective AAST Open Abdomen Registry

Objective:Studies have failed to consistently demonstrate improved survival in intensive care unit (ICU) patients receiving immune-modulating nutrient-enhanced enteral feeds when compared with standard enteral feeds. The objective was to study in a prospective fashion the effects of adding glutamine to standard or immune-modulated (supplemented with omega-3 fatty acids, β-carotene, and amino acids such as glutamine and arginine) tube feeds. Design:Prospective, unblinded study using sequential allocation. Setting:A university surgical trauma ICU. Patients:All surgical and trauma patients admitted to the surgical trauma ICU at a university hospital over a 3-yr period who were to receive enteral feeds (n = 185). Interventions:Sequential assignment to three isocaloric, isonitrogenous diets was performed as follows: standard 1-kcal/mL feeds with added protein (group 1), standard feeds with the addition of 20–40 g/day (0.6 g/kg/day) glutamine (group 2), or an immune-modulated formula with similar addition of glutamine (group 3). The goal for all patients was 25–30 kcal/kg/day and 2 g/kg/day protein. Measurements and Main Results:Patients were followed until discharge from the hospital. The primary end point was in-hospital mortality, and multiple secondary end points were recorded. In-hospital mortality for group 1 was 6.3% (four of 64) vs. 16.9% (ten of 59, p = .09) for group 2 and 16.1% (ten of 62, p = .09) for group 3. After controlling for age and severity of illness, the difference in mortality between patients receiving standard tube feeds and all patients receiving glutamine was not significant (p ≤ .11). There were no statistically significant differences between the groups for secondary end points. Conclusions:The addition of glutamine to standard enteral feeds or to an immunomodulatory formula did not improve outcomes. These findings suggest that enteral glutamine should not be routinely administered to patients with surgical critical illness.

Predictors of patients who will develop prolonged occult hypoperfusion following blunt trauma.

INTRODUCTION Nonoperative management (NOM) of blunt splenic injury has become the preferred treatment for hemodynamically stable patients. The application of splenic artery embolization (SAE) in NOM has been controversial. We hypothesized that incorporation of initial use of SAE into a practice protocol for patients at high risk for NOM failure (contrast extravasation or pseudoaneurysm on computed tomography, grade 3 injury with large hemoperitoneum, grade 4 injuries) would improve patient outcomes. METHODS A retrospective analysis of three continuums of practice was performed: group I (January 1991-June 1998), SAE not part of routine NOM; group II (July 1998-December 2001), introduction and discretionary use of SAE; and group III (January 2002-June 2007), standardized use of initial SAE for patients considered at high risk of nonoperative failure. The primary outcome measure was the success of NOM. Failure of NOM was defined as the need for abdominal operation. Secondary outcomes were mortality, length of stay, and splenic salvage. RESULTS Over 16 years, 815 patients with blunt splenic injury were treated at our level 1 trauma center. There were 222 patients in group I, 195 in group II, and 398 in group III. There was an increase in the use of SAE over time with a significant improvement in the utilization of NOM (61% in group I; 82% in group II; 88% in group III; p < 0.05). This was associated with an increase in successful NOM (77%, group I; 94%, group II; 97%, group III; p < 0.0001 group I vs. group II and III). Mortality, length of stay, and splenic salvage were similar in groups II and III but significantly improved when compared with group I. CONCLUSIONS The increased use of initial SAE in high-risk patients expanded the successful use of NOM but was not associated with other incremental improvements.