Journal Club Round up June 13, 2009
(1) THE SENSITIVITY OF COMPUTED TOMOGRAPHY (ct) SCANS IN DETECTING TRAUMA: ARE CT SCANS RELIABLE ENOUGH FOR COURTROOM TESTIMONY? Molina, D.K., et al, J Trauma 63:625, September 2007
BACKROUND: Missed injuries in trauma patients can have substantial medicolegal consequences. CT scanning is often considered the “gold standard” in trauma, but it is not certain how often important injuries are missed by this imaging modality. METHODS: These authors, forensic pathologies from Medical Examiner’s office in Texas, identified 113 trauma patients who had undergone a CT scan during the 24 hours before death, without any intervening surgery. They compared the CT findings, as reported by a board-certified radiologist at the time the study was performed, to the results of an autopsy by one of an unknown number of pathologists, who were blinded to the reported CT results. RESULTS: The sensitivity of the CT scan was 26% for skull fracture and 47% for intracranial hemorrhage of any kind. CT of the neck failed to identify any of the five patients with a cervical fracture, and reported only one of the six cervical dislocation found at autopsy. Abdominal CT identified only seven of the 16 patients with solid organ injury at autopsy. The overall sensitivity for fracture was 30%. CONCLUSIONS: Although selection bias might have impacted these results, and although some of the findings might not have been clinically important, CT scanning appeared to have missed many injuries identified at autopsy in this series of patients who died following trauma.
(2)
DIGITAL NERVE BLOCKS? Waterbrook, A.L., et al, Ann Emerg Med 50(4):472 October 2007METHODS: The authors, from Maine Medical Center in Portland, reviewed seven published papers evaluating the safety of epinephrine in conjunction with local anesthesia for digital nerve block. RESULTS: In two trials, in which the block was performed in 103 patients randomized to lidocaine with or without epinephrine, no patient randomized to lidocaine plus epinephrine developed digital necrosis or vascular insufficiency; the epinephrine groups were less likely to require additional anesthetic injections or ancillary measures to control bleeding, and had a longer duration of post-procedure pain relief. In a prospective series 3,110 blocks performed by nine hand surgeons using low-dose epinephrine (1:100,000), there were no cases of digital ischemia and no patient required treatment with phentolamine to reserve the effects of epinephrine. In one series of 24 patients, Doppler studies demonstrated a decrease in blood flow ten minutes after lidocaine/epinephrine block, with restoration of flow within 60-90 minutes without complications. Only 21 of 48 cases of digital necrosis after local anesthesia identified in three literature reviews involved the use of epinephrine. The overwhelming majority of these cases occurred prior to 1950, when the concentration of epinephrine was not standardized, (acidic) procaine was the anesthetic of choice and dubious management techniques were often employed. No cases have been reported with current commercially available formulations of epinephrine plus lidocaine. CONCLUSIONS: Using a currently available commercial formulation of epinephrine plus lidocaine for a digital nerve block does not appear to be harmful.
(3)
THE RATIO OF BLOOD PRODUCTS TRANSFUSED AFFECTS MORTALITY IN PATEINTS RECEIVING MASSIVE TRANSFUSSIONS AT A COMBAT SUPPORT HOSPITAL Borgman, M.A., et al, J Trauma 63(4):805, October 2007 BACKGROUND: Among trauma patients requiring massive transfusions (ten or more RBC units in 24 hours0, morality rates have ranged between 20% and 50%, likely due to the “lethal triad” of hypothermia, metabolic acidosis and coagulopathy. It has recently been recommended that such patients receive RBC’s fresh frozen plasma and platelets in 1:1:1 ratio. METHODS: The authors, from BrookeArmyMedicalCenter, examined the relationship between the ratio of plasma to RBCs and morality in 246 combat causalities requiring massive transfusions that were treated at a combat support hospital. RESULTS: The patients were divided into three groups representing a low (1:8), medium (1:2.5) or high (1:1.4) ratio of transfused plasma to RBC units. A significant decrease in mortality was observed as this ratio increased. Specifically, the morality rate was 65% in the low ratio group, 34% in the medium ration group, and 19% in the high ration group. Patients in the high ration group also had a lower rate per hour for administration of crystalloid and RBC units during the first 24 hours. Among nonsurvivors, the medium ration group, but 38 hours in the high ration group. The percentage of deaths analysis, there was a significant association between the plasma to RBC ratio and the likelihood of survival (odds ratio 8.6). CONCLUSION: These findings support 1:1 plasma to RBC ratio for trauma patients requiring massive transfusions.
(4)
ACUTE APPENDICITIS: DIAGNOSTIC VALUE OF NONEHANCED CT WITH SELECTIVE USE OF CONTRAST IN ROUTINE CLINICAL SETTINGS Tamburruni, S., et al, Eur Radiol 17(8):2055, August 2007
BACKGROUND: There is disagreement regarding the need fir contrast enhancement in patients undergoing CT scanning for possible appendicitis. METHODS: This study, from Naples, Italy, and UC San Diego, reviewed CT readings and clinical charts in 536 patients with suspected appendicitis who received CT scanning according to a protocol which called for initial unenhanced scanning followed by repeat scanning with contrast at the discretion if the initial scan was felt to be inconclusive. The accuracy of CT interpretation was based on findings at laparotomy or on clinical follow-up in patients with a reportedly negative scan. RESULTS: The initial unenhanced CT was judged to be conclusive in 75% of the patients. Repeat scanning with contrast was performed in all but six of the remaining 132 patients, with contrast choices including IV administration in 118 cases, and oral and rectal administration in 33 and 12 cases respectively (37 patients received contrast by more than one route). The sensitivity and specificity of the initial scans were 90% and 96%, respectively, and for the entire group (including all those who had a second, contrast-enhanced, CT) was 91%, respectively. CONCLUSIONS: CT scanning without contrast was reasonably accurate in the three-quarters of cases in which it was felt to be “conclusive”. Selective repeat scanning with contrast enhancement maintained essentially the same overall accuracy, even including those patients whose initial scan was inconclusive, but would lead to the costs and radiation exposure incurred by a second scan.
(5)
A SYSTEMATIC REVIEW OF MEDICAL THERAPY TO FACILITATE PASSGAE OF URETERAL CALCULI Singh, A., et al, Ann Emerg MED 50(5):552, November 2007BACKGROUND: Alpha-antagonists and calcium channel blockers (CCBs) have been reported to inhibit the contraction of ureteral muscle and to facilitate passage of distal ureteral stones. METHODS: The authors, from AlamedaCountyMedicalCenter in Oakland, CA, performed a systematic review of randomized, controlled trials of medical expulsive therapy in adults with distal ureteral calculi. The review included 16 trails (1,235 patients) of alpha-antagonists (tamsulosin [Flomax] in 13 of the 16 trails) and nine trails (686 patients) of CCBs (usually nifedipine). RESULTS: In the alpha-antagonist trials, follow-up ranged between one and seven weeks (median, four weeks) and stone sizes ranged between 3-18mm (mean, 5mm). When combined with standard treatment )analgesics and encouraged fluid intake), active treatment had a beneficial effect on stone expulsion (risk ratio [RR] 1.59, 95% CI 1.44-1.75) (number-needed- to-treat [NNT] 3.3), and the average improvement in time to passage was two to six days. In the CCB trials, follow-up ranged between three and seven weeks (median, four weeks) and the average stone size exceeded 5mm in six of the nine studies. When combined with standard treatment, CCB administration had a beneficial effect on stone expulsion (RR 1.5, 95% CI 1.34-1.68, NNT 3.9), and seven studies reported a reduction in the interval to expulsion (median interval, less than 28 days). Adverse effects were reported in 4% of the patients in the alpha-antagonist trails (discontinuation rate 0.2%) and in 15.2% of those in the CCB trials (discontinuation rate 2.9%).. CONCLUSIONS: In adults with a moderate sized distal ureteral calculus, medical expulsive therapy with an alpha-antagonist or CCB increases the rate of stone expulsion. 91 references 3/08-#26
(6)
HYDROCORTISONE THERAPY FOR PATIENTS WITH SEPTIC SHOCK Sprung, C.L., et al, N Engl J Med 358(2):111, January 10, 2008METHODS: In the multinational, prospective, double-blind, 52-ICU “Corticosteroid Therapy of Septic Shock” (CORTICUS) study, 499 adults with septic shock were randomized to IV hydrocortisone (50mg every six hours for five days and then tapered over the next six days) or placebo. The primary endpoint was 28-days mortality, with stratified analysis according to the patients’ response to corticotrophin testing (previously suggested to be a maker of the likely response to steroid treatment). RESULTS: Just under half the patients (46.7%) did not exhibit a response to corticotrophin, and these patients had a worse outcome. However, there were no differences between the hydrocortisone or placebo-treated groups in 28-day mortality (34.3% vs. 31.5% overall, and 28.8% vs.28.7% and 39.2% vs. 36.1% in those with and without a response to corticotrophin, respectively). There was, likewise, no difference in the percentage of patients in whom shock was reversed (79.7% in the hydrocortisone group and 74.2% in controls overall, and 84.7% vs. 76.5% and 76% vs. 70.4% in the two subgroups), although the median interval to reversal of shock was significantly shorter (by about 2-3 days) in the hydrocortisone group overall and in the corticotrophin response subgroups. When compared with controls, the hydrocortisone group had a higher incidence of superinfection (33% vs. 26%, relative risk [RR] 1.27), new episodes of septic shock (6% vs. 2%, RR 2.78), hyperglycemia (85% vs. 72%, RR 1.18) and hypernatremia (29% vs. 18%, RR 1.58). CONCLUSIONS: In this large study, low dose hydrocortisone treatment of patients with septic shock did not reduce 28-days mortality, regardless of the results of corticotrophin testing. 39 references 5/08-#27
(7)
NOREPINEPHRINE PLUS DOBUTAMINE VERSUS EPINEPHRINE ALONF FOR MANAGEMENT OF SEPTIC SHOCK: A RANDOMISED TRAIL Annane, D., et al, Lancet 370:676 August 25, 2007BACKGROUND: There is uncertainty regarding the optimum vasopressor / inotrope or combinations of agents for the treatment of septic shock. METHODS: These French authors carried out a prospective, multicenter, randomized, double-blinded, controlled trial of epinephrine vs. norepinephrine and dobutamine in 330 patients admitted to one of 19 French intensive care units. These agents were titrated to achieve and maintain a mean blood pressure of greater than 70mm Hg. The primary outcome was 28-day all-cause mortality. RESULTS: Patients in the two groups had similar clinical characteristics, except that the epinephrine group was slightly older (mean 65 vs. 60 years). There was no statistical difference in the primary outcome of 28-days mortality: 64 deaths (40%) in the epinephrine group and 58 deaths (34%) in the norepinephrine-dobutamine group, relative risk 0.86 (95% CI 0.65-1.14). In addition, there were no differences between the two groups in any of the secondary endpoints, or in serious adverse events. CONCLUSIONS: There appears to be no difference in either efficacy or safety between epinephrine or the combination of norepinephrine and dobutamine for the treatment of patients with septic shock.
(8)
INTENSIVE INSULIN THERAPY AND MORTALITY IN CRICICALLYILL PATINETS Treggiari, M.M., et al, Crit Care 12(1):R29, February 29, 2008BACKGROUND: Studies if the effects of intensive insulin therapy in critically ill patients yielded conflicting results. METHODS: This study evaluated the outcomes of 10,456 patients admitted to one of seven ICUs at Harborview Medical Center in Seattle during three periods corresponding to changing protocols for glycemic control in the ICU: 2,366 treated when there was no specific protocol and hyperglycemia was treated by a mix of subcutaneous and IV insulin to a general target blood glucose level of 120-180mg/dl; 3,322 treated when the target level was 80-130mg/dl; and 4,768 treated when the target was 80-110mg/dl. The intensive insulin protocols stipulated explicit blood sugar ranges and dosing orders for IV insulin, and included educational programs for nurses and physicians. RESULTS: The percentage of patients receiving insulin infusions increased from 9% in period one to 25% in period two and 43% in period three to four-fold increase in episodes of moderate to severe hypoglycemia from period one to period three. The average 6am blood glucose levels were not within the target range (144mg/dl in period one, 139mg/dl in period two and 129mg/dl in period three) ICU mortality rates in period one, two and three were 9.04%, 10.78% and 9.75%, respectively, and corresponding inpatient mortality rates were 14.2%, 15.71% and 14.39%, respectively. After adjustment for confounders, there was an increased risk of death during period three compares with period one (odds ratio [OR] 1.15), largely reflecting excess mortality in patients with an ICU length of stay of three days or less. CONCLUSIONS: In this large study of ICU patients, intensive insulin therapy was not associated with a decrease in mortality. 55 references 8/08-#19
(9)
RAMDOMIZED, DOUBLE-BLINDED, PLACEBO-CONTROLLED TRAIL OF CEPHALEXIN FOR TREATMENT OF UNCOMPICATED SKIN ABCESSES IN A POPULATION AT RISK FOR COMMUNITY-ACQUIRED METHICILLIN-RESISTANT STAPHYLOCOCCUS AUREUS INFECTION Rajendran, P.M., el al, Antimicrob Agents Chemother 51(11):4044, November 2007BACKGROUND: Although uncomplicated skin abscesses respond to simple incision and drainage (I&D) without antibiotics, a survey published in 2005 found that 87% of providers prescribe antibiotics (typically a beta-lactic) after I&D in such patients. METHODS: In this study, from San Francisco GeneralHospital, 166 adult requiring I&D of an uncomplicated skin abscess were randomized to a seven-day course of oral cephalexin (500mg four times a daily) or placebo. RESULTS: In the study population there was a high rate of homelessness (35-40%), hepatitis B or C (31-33%) and HIV infection (16% in the cephalexin group and 7% in controls). S. aureus was isolated from 70.4% of the 162 wounds that were cultured, and methicillin-resistant S. aureus (MRSA) accounted for 88% of the S. aureus isolated that were tested for antibiotic susceptibility. There was no statistical difference between the cephalexin and placebo treated control groups in clinical cure rate (84% vs. 91% respectively). CONCLUSIONS: In these high-risk patients with an uncomplicated skin abscess, most of which were caused by MRSA, clinical cure was achieved in the large majority with I&D alone, either without any antibiotics or with an antibiotic not achieve against MRSA. 30 references 6/08
(10)
ANTIBIOTICS NECESSARY AFTER INCISION AND DRAIANGE OF A CUTANEOUS ABSCESS? Hankin, A., et al, Ann Emerg Med 50(1):49, July 2007BACKGROUND: Both the CDC-P and the Infectious Disease Society of American recommend incision and drainage (I&D) alone, without antibiotics, for most patients with a simple cutaneous abscess, and use of an antibiotic effective against MRSA only of the abscess is persistent or recurrent. METHODS: The authors, from the University of Pennsylvania, reviewed five research studies abd one abstract concerning the management of simple abscesses. RESULTS: Two ramdomized, controlled trials performed in the 1970s and early 1980s reported no clear advantage of antibiotics in addition to I&D. In one trial published in 2006 and involving patients with comorbidities and at increased risk for MRSA infection, wound cultures were positive for MRSA in 52%. A course of cephalexin following I&D did not significantly improve resolution rates, which exceeded 90% in placebo-treated controls. Similar findings were noted in two prospective studies (one involving children with an abscess culture-positive for MRSA and the other involving adults presenting to a university-affiliated ED in one of eleven U.S. cities [cultures positive for MRSA in nearly half of these latter patients]). In both of these studies, most patients in all treatment groups experienced complete resolution of the abscess after I&D, including those receiving an antibiotic that was ineffective against the causative organism. A retrospective study involving 441 abscesses (64% due to MRSA) reported similar conclusions. CONCLUSIONS: These findings do not support the routine use of antibiotics, in addition to I&D, in patients with a simple Cutaneous abscess, including those residing in an area in which MRSA is prevalent. 8 references 11/07-#10
(11)
THE OPALS MAJOR TRAUMA STUDY: IMPACT OF ADVANCD LIFE-SUPPORT ON SURVIVAL AND MORBILITY Stiell, I.G., et al, Can Med Assoc J 178(9):1141, April 22, 2008BACKGROUND: Within large North American cities, provision of prehospital advanced life support (ALS) has become relatively standard for patients sustaining major trauma, but its effectiveness has not been clearly established. METHODS: In a before-after format, the 17-city “Ontario Prehospital Advanced Life Support” )OPALS) major trauma study compared outcomes in 1,373 adult with Injury Severity Scores (ISS) above 12 who received basic life support (BLS) in the prehospital setting and 1,494 similar patients who received prehospital ALS care. RESULTS: The median ISS was 24 in the BLS phase and 22 in the ALS phase, and median Revised Trauma Scores were 7.84% in both phases. Among patients managed during the ALS phase, 6.8% were intubated in the field (71.8% success rate), IV access was established in 63% (90.3% success rate), and 11.7% received IV fluid bolus therapy. The overall rate of survival todischarge was 81.8% during the BLS phase and 81.1% during the ALS phase, and corresponding mortality rates during the initial 24 hours after injury were 7.0% abd 7.2%, respectively. No subgroup was identified that has significantly better outcomes during the ALS phase, and the patients with a GCS below 9 had a lower survival rate during the ALS phase (51.2% vs. 60.1% during the BLS phase). Among patients who survived to discharge, there were no significant differences between the twp phases in Glasgow Outcome Scale scores or measures of functional independence. CONCLUSION: The authors suggest that EMS systems should reevaluate the implementation of advanced life support programs for the prehospital care of patients sustaining major trauma. 40 references 8/08-#40
(12)
REVIEW OF MANAGEMENT OF PRIMARY SPONTANEOUS PNEUMOTHORAX: IS THE BEST EVIDENCE CLEARER 15 YEARS ON? Kelly, A.M., Emerg Med Australasia 19:303, august 2007BACKGROUND: A review on the management of primary spontaneous pneumothorax (PSP) published in 1993 noted a dearth of high-quality evidence on which base management. METHODS: This Australian author reexamined the evidence of PSP management to determine if treatment choices have been clarified in the interim. RESULTS: Methods of estimating the size of PSP, including plain x-ray and nomogram-based mathematic calculations, have generally been derived from limited patient populations with small pneumothoraces; most have not been validated, and they have also been found to be unreliable. In the absence of respiratory and/or hemodynamic compromise, various treatment options are available. Reported success rates are 90% with conservative management, 50-83% with needle aspiration, 66-97% with intercostals catheter drainage, and 74-100% with small bore or pigtail catheter drainage. Three guidelines have been published for PSP management (British Thoracic Society [2003], American College of Chest Physicians [ACCP] [2004] abd the Belgian Society of Pneumology [2005]). While all three advocate conservative management for a small PSP. The ACCP guideline recommends conservative management for a small PSP with ED observation for 3-6 hours followed by the outpatient management if progression is excluded on chest x-rays. For a large PSP in a stable patient, the ACCP guidelines advocates reexpansion using a small-bore catheter or chest tube placement, with hospital admission in most cases. CONCLUSIONS: The author cites the need for performance of high-quality studies of optimal PSP management. 59 references 12/07-#36