Shock associated with endothelial dysfunction in omental microvessels.

BACKGROUND: Impaired microvascular function leads to a poor outcome in a variety of medical conditions. Our aim was to determine whether vasodilator responses to acetylcholine (Ach) are impaired in human omental arterioles from patients with severe trauma. MATERIALS AND METHODS: Patients with massive blood loss and severe shock requiring damage control procedures were included. Tissues were collected at the first (FEL) and the second explorative laparotomy (SEL). Control tissues were collected from nontrauma patients. Freshly isolated 50-200-µm-diameter omental arterioles were analysed using videomicroscopy. Dihydroethidine and DCF-DA fluorescence were used to assess reactive oxygen species (ROS) production. MnTBAP was used to determine the contribution of excess vascular superoxide contribution to endothelial dysfunction. RESULTS: After constriction (30-50%) with endothelin-1, dilation to graded doses of Ach (10-9 -10-4 M) was greater in control vessels compared to FEL and SEL (max dilation at 10-4 M (MD) = 25 ± 3%, n = 8; and 59 ± 8%, n = 8, respectively, and controls MD = 93 ± 10%, n = 6, P < 0·05). Fluorescence imaging of ROS production showed significant increases in superoxide (225·46 ± 12·86; 215·77 ± 10·75 vs. 133·75 ± 7·26, arbitrary units; P < 0·05) and peroxide-related ROS (240·8 ± 20·42; 234·59 ± 28·86, vs. 150·78 ± 15·65, arbitrary units; P < 0·05), in FEL and SEL microvessels compared to control, respectively. FEL pretreated with MnTBAP demonstrated significant improvement in Ach-induced vasodilation (25·5 ± 3·0% vs. 79·5 ± 8·2%; P < 0·05). CONCLUSIONS: Severe shock associated with microvascular endothelial dysfunction enhances production of ROS in human omental tissues. The altered flow regulation may contribute to a mismatch between local blood supply and demand, exacerbating abnormal tissue perfusion and function.

Undetected penetrating bladder injuries presenting as a spontaneously expulsed bullet during voiding: a rare entity and review of the literature.

BACKGROUND: Patients presenting with a penetrating missile lodged in the pelvis are at risk for having a urinary tract injury. Once in the bladder, the missile can become impacted in the urethra, causing retention that requires extraction. Rarely, the missile can be expulsed spontaneously through the urethra. OBJECTIVES: To describe the world literature regarding undetected penetrating bladder injuries presenting as spontaneously voided bullets and to contribute an additional case to the literature. CASE REPORT: We present a case report of a 37-year-old man who sustained a gunshot wound to the right buttock, with an undetected urinary system injury and subsequent spontaneous voiding of a bullet. CONCLUSION: There have been <10 cases reported in the literature of spontaneously expulsed bullets from the urethra, all of which were undetected injuries on initial presentation. Physicians should be aware of the potential for undetected urinary tract injuries in patients with penetrating missiles to the pelvis and understand the appropriate evaluation and management strategies for these injuries.

Ketamine infusion for pain control in elderly patients with multiple rib fractures: Results of a randomized controlled trial.

BACKGROUND: Rib fractures are associated with increased mortality, particularly in the elderly. While opiate-based pain regimens remain the cornerstone of rib fracture management, issues related to opioids have driven research into alternative analgesics. Adjunctive ketamine use in lieu of opioids continues to increase but little evidence exists to support its efficacy or safety within the elderly trauma population. METHODS: A prospective, randomized, double-blind placebo-controlled trial of elderly patients (age, ≥65 years) with three or more rib fractures admitted to a Level I trauma center was conducted. Exclusion criteria included Glasgow Coma Scale score less than 14, and chronic opiate use. Groups were randomized to either low-dose ketamine (LDK) at 2 µg·kg·min or an equivalent rate of 0.9% normal saline. The primary outcome was reduction in numeric pain scores (NPS). Secondary outcomes included oral morphine equivalent (OME) utilization, epidural rates, pulmonary complications, and adverse events. RESULTS: Thirty (50.8%) of 59 were randomized to the experimental arm. Groups were similar in makeup. Low-dose ketamine failed to reduce 24-hour NPS or OME totals. Subgroup analysis of 24 patients with Injury Severity Score greater than 15 demonstrated that LDK was associated with a reduction in OME utilization the first 24-hours (25.6 mg vs. 42.6 mg, p = 0.04) but at no other time points. No difference in other secondary outcomes or adverse events was noted. CONCLUSION: Low-dose ketamine failed to affect NPS or OME within the overall cohort, but a decrease in OME was observed in those with an Injury Severity Score greater than 15. Additional studies are necessary to confirm whether LDK benefits severely injured elderly patients. LEVEL OF EVIDENCE: Therapeutic, level I.

Ketamine infusion for pain control in adult patients with multiple rib fractures: Results of a randomized control trial.

BACKGROUND: Rib fractures occur in up to 40% of trauma patients and are associated with increased mortality. Opiate-based pain regimens remain the cornerstone of rib fracture management; however, concerns around opioids have fostered interest in alternative analgesics. Ketamine is currently being used in lieu of opioids, but little evidence exists supporting its use within the trauma population. METHODS: A prospective, randomized, double-blind placebo-controlled trial of adult patients with three or more rib fractures admitted to a Level I trauma center was conducted. Exclusion criteria included age older than 64 years, Glasgow Coma Scale score less than 13, and chronic opiate use. The experimental arm received low-dose ketamine (LDK) at 2.5 µg·kg·min while the placebo cohort received an equivalent rate of 0.9% normal saline. All infusions were continued for 48 hours. The primary outcome was reduction in numeric pain score (NPS) during the first 24 hours. Secondary outcomes studied included oral morphine equivalent (OME) utilization, length of stay, epidural rates, pulmonary complications, and adverse events. RESULTS: Forty-five (49%) of 91 patients were randomized to the experimental arm. Both groups were similar in makeup. Overall, 74.7% were male, had a median age of 49 years, and an Injury Severity Score (ISS) of 14. Low-dose ketamine was not associated with a significant reduction in 24-hour NPS or OME totals. Subgroup analysis of 45 severely injured patients (ISS, >15) demonstrated that LDK was associated with a significant reduction in OME utilization during the first 24 hours (35.7 vs. 68, p = 0.03), 24 hours to 48 hours (64.2 vs. 96, p = 0.03), and overall (152.1 vs. 198, p = 0.048). No difference in other secondary outcomes or adverse events was noted. CONCLUSION: Low-dose ketamine failed to decrease NPS or OME within the overall cohort, but a decrease in OME was observed among patients with an ISS greater than 15. Confirmatory studies are necessary to determine if LDK is a useful adjunct among severely injured patients. LEVEL OF EVIDENCE: Therapeutic study, level II.

Effective retention of primary survey skills by medical students after participation in an expanded Trauma Evaluation and Management course.

BACKGROUND: The Trauma Evaluation and Management (TEAM) module orients medical students to the initial assessment of an injured patient. At the Medical College of Wisconsin, a course based on expanded TEAM (eTEAM) was developed for junior medical students. This study determined whether eTEAM improved the ability to perform and retain primary survey skills. METHODS: Objective Structured Clinical Examination methodology was used to compare 2 groups of senior medical students 1 year after receiving either a 2-hour lecture or eTEAM. RESULTS: Students receiving eTEAM performed the primary survey much better than those receiving lecture alone. The overall Objective Structured Clinical Examination scores did not differ between groups. CONCLUSIONS: Medical students participating in eTEAM retained the ability to perform a primary survey in proper sequence 1 year later better than students receiving the information in lecture format only.

Rib fracture stabilization in patients sustaining blunt chest injury.

Conservative management for the majority of patients with severe chest injuries has produced a reduction in mortality, complications, and hospital length of stay. More recently, operative stabilization of rib fractures has been used with the implication of improved outcome. We assessed the impact of operative rib fracture stabilization on outcome among trauma patients. A matched case-control study of patients undergoing operative rib fracture stabilization was performed. Thirty patients undergoing rib stabilization were matched with 30 controls. Length of intensive care unit (controls, 14.1 +/- 2.7 vs cases, 12.1 +/- 1.2, P = 0.51) and total hospital (controls, 21.1 +/- 3.9 vs cases, 18.8 +/- 1.8, P = 0.59) stay were similar for both groups. There was a trend toward fewer total ventilator days for operative patients (6.5 +/- 1.3 days vs 11.2 +/- 2.6 days, P = 0.12). Ventilator days for operative patients from the time of stabilization was 2.9 +/- 0.6 days compared with 9.4 +/- 2.7 days in controls (P = 0.02). Rib fracture fixation may reduce ventilator requirements in trauma patients with severe thoracic injuries. Long-term functional outcomes need to be assessed to ascertain the impact of this procedure.

The value of process measures in evaluating an evidence-based guideline.

BACKGROUND: Linking the process of evidence-based guidelines to outcomes is difficult. We hypothesized that the process of implementing an evidence-based clinical guideline for blunt splenic trauma would reduce resource consumption and improve outcome. METHODS: Time periods were divided into period 1 (7/1/96-6/30/99) and period 2 (7/1/99-6/30/01). On 7/1/99 our American College of Surgeons-verified level I trauma center instituted an evidence-based approach for managing splenic trauma incorporating hemodynamic normality as the process measure triggering clinical decisions. Outcomes included the number of hemodynamically normal patients treated without operation, patient death, length of stay, and cost. RESULTS: Two hundred thirty-one patients had blunt splenic injury; 115 patients were seen during period 1 and 116 during period 2. Hemodynamically normal patients undergoing splenectomy decreased during period 2 (P<.05). Median length of stay was 8 days in period 1 and 6 days in period 2 (P<.03). Cost per patient was $34,972 US dollars in period 1 and $24,037 US dollars in period 2 (P<.03). The mortality rate was unchanged. CONCLUSIONS: Compliance with evidence-based data in the management of blunt splenic injury improved rates of nonoperative management, decreased hospital days, and did not change mortality rates. An evidence-based clinical guideline evaluated with process measures can reduce resource use and improve outcome in a trauma program.

Comparative in vitro antimicrobial activity of a novel quinolone, garenoxacin, against aerobic and anaerobic microbial isolates recovered from general, vascular, cardiothoracic and otolaryngologic surgical patients.

OBJECTIVES: The aim of the study was to analyse the susceptibility of unique and non-duplicate aerobic and anaerobic isolates from surgical patients to a novel des-F(6)-quinolone (garenoxacin) and other selected antimicrobial agents. METHODS: Eleven hundred and eighty-five aerobic and anaerobic isolates from general, vascular, cardiothoracic and otolaryngologic surgical patients were tested for susceptibility to garenoxacin and seven other antibiotics (ciprofloxacin, moxifloxacin, levofloxacin, piperacillin/tazobactam, imipenem, clindamycin and metronidazole) using the referenced microbroth and agar-dilution method. RESULTS: Garenoxacin exhibited greater antimicrobial activity than comparator quinolones such as ciprofloxacin, levofloxacin and other antimicrobials when tested against selected gram-positive organisms. The in vitro aerobic and anaerobic activity of garenoxacin was similar to that of moxifloxacin. All fluoroquinolones tested were effective against most gram-negative facultative anaerobes including Escherichia coli. Garenoxacin and moxifloxacin demonstrated similar in vitro antimicrobial activity against selected anaerobic gram-positive and gram-negative anaerobic bacteria such as members of the Bacteroides fragilis group. Overall, the in vitro activity of the advanced spectrum quinolones against anaerobic surgical isolates compared favourably with selected comparator agents, metronidazole, imipenem and piperacillin/tazobactam. CONCLUSIONS: These findings suggest that 82.4% of aerobic surgical isolates were susceptible to a concentration of garenoxacin < or = 1.0 mg/L, whereas 84.5% of the anaerobic isolates were susceptible to a garenoxacin concentration < or = 1.0 mg/L. Garenoxacin may be a valuable surgical anti-infective for treatment of serious head and neck, soft tissue, intra-abdominal and diabetic foot infections.

Effect of gender on endothelium-dependent dilation to bradykinin in human adipose microvessels.

We examined the influence of gender and climacteric status, two coronary risk factors, on bradykinin (BK)-induced dilation in adipose arterioles from men and women of different ages [premenopausal women (Pre-W), postmenopausal women (Post-W), and similar aged men (Y-M and O-M), respectively]. We examined the responses from both omental (more closely associated with coronary disease) and subcutaneous fat. Tissues were obtained at surgery and cannulated (60 mmHg) for measurement of internal diameter. In vessels from omental tissue, dilation to BK was more sensitive in Pre-W than other groups, whereas in vessels from subcutaneous tissue, sensitivity to BK was greater in both Pre-W and Post-W compared with Y-M and O-M. Maximal dilation was similar among groups. Indomethacin (Indo; 10(-5) M) alone had no effect on dilation to BK in any groups, but Indo and N(omega)-nitro-L-arginine methyl ester (L-NAME; 10(-4) M) reduced dilation to BK in Pre-W more than in Y-M. L-NAME increased dilation to BK in subcutaneous fat from Y-M but had no effect in Post-W and O-M. Indo- and L-NAME-resistant dilation in all vessels was markedly reduced by 30 mM KCl. There was no difference in sodium nitroprusside-induced dilation among groups. We conclude that gender and climacteric state contribute to mechanisms of microvascular regulation in humans. Functional vascular differences in visceral and subcutaneous fat may underlie the proposed differential influence of these tissues on cardiovascular risk.