Timing of Abdominal CT Evaluation Impacts the Diagnosis of Paraduodenal Hernia.

Internal hernias are the causes of 0.5 to 5.8 per cent of all cases of small bowel obstruction. Left paraduodenal hernia (PDH) is the most common congenital internal hernia encountered in adults. The symptoms and physical findings associated with PDH are vague and nonspecific before the onset of complicated intestinal obstruction. Diagnoses are most commonly established by CT. This case presentation and review is intended to promote clinicians' awareness of this unusual but potentially highly morbid condition, discuss CT findings associated with PDH, and illustrate the importance of timing in the acquisition of diagnostic abdominal CT scans.

Hospital-centered violence intervention programs: a cost-effectiveness analysis.

BACKGROUND: Hospital-centered violence intervention programs (HVIPs) reduce violent injury recidivism. However, dedicated cost analyses of such programs have not yet been published. We hypothesized that the HVIP at our urban trauma center is a cost-effective means for reducing violent injury recidivism. METHODS: We conducted a cost-utility analysis using a state-transition (Markov) decision model, comparing participation in our HVIP with standard risk reduction for patients injured because of firearm violence. Model inputs were derived from our trauma registry and published literature. RESULTS: The 1-year recidivism rate for participants in our HVIP was 2.5%, compared with 4% for those receiving standard risk reduction resources. Total per-person costs of each violence prevention arm were similar: $3,574 for our HVIP and $3,515 for standard referrals. The incremental cost effectiveness ratio for our HVIP was $2,941. CONCLUSION: Our HVIP is a cost-effective means of preventing recurrent episodes of violent injury in patients hurt by firearms.

BRAF mutation in papillary thyroid cancer: A cost-utility analysis of preoperative testing.

BACKGROUND: Papillary thyroid carcinoma (PTC) with BRAF mutation carries a poorer prognosis. Prophylactic central neck dissection (CND) reduces locoregional recurrences, and we hypothesize that initial total thyroidectomy (TT) with CND in patients with BRAF-mutated PTC is cost effective. METHODS: This cost-utility analysis is based on a hypothetical cohort of 40-year-old women with small PTC [2 cm, confined to the thyroid, node(-)]. We compared preoperative BRAF testing and TT+CND if BRAF-mutated or TT alone if BRAF-wild type, versus no testing with TT. This analysis took into account treatment costs and opportunity losses. Key variables were subjected to sensitivity analysis. RESULTS: Both approaches produced comparable outcomes, with costs of not testing being lower (-$801.51/patient). Preoperative BRAF testing carried an excess expense of $33.96 per quality-adjusted life-year per patient. Sensitivity analyses revealed that when BRAF positivity in the testing population decreases to 30%, or if the overall noncervical recurrence in the population increases above 11.9%, preoperative BRAF testing becomes the more cost-effective strategy. CONCLUSION: Outcomes with or without preoperative BRAF testing are comparable, with no testing being the slightly more cost-effective strategy. Although preoperative BRAF testing helps to identify patients with higher recurrence rates, implementing a more aggressive initial operation does not seem to offer a cost advantage.

Pan computed tomography versus selective computed tomography in stable, young adults after blunt trauma with moderate mechanism: a cost-utility analysis.

BACKGROUND: Pan computed tomography (PCT) of the head, cervical spine, chest, abdomen, and pelvis is a valuable approach for rapid evaluation of severely injured blunt trauma patients. A PCT strategy has also been applied for the evaluation of patients with lower injury severity; however, the cost-utility of this approach is undetermined. The advantage of rapidly identifying all injuries via PCT must be weighed against the risk of radiation-induced cancer (RIC). Our objective was to compare the cost-utility of PCT with selective computed tomography (SCT) in the management of blunt trauma patients with low injury severity. METHODS: A Markov model-based, cost-utility analysis of a hypothetical cohort of hemodynamically stable, 30-year-old males evaluated in a trauma center after motor vehicle crash was used. CT scans are performed based on the mechanism of injury. The analysis compared PCT with SCT over a 1-year time frame with an analytic horizon over the lifespan of the patients. The possible outcomes, utilities of health states, and health care costs including RIC were derived from the published medical literature and public data. Costs were measured in US 2010 dollars, and incremental effectiveness was measured in quality-adjusted life-years (QALYs) with 3% annual discounted rates. Multiway sensitivity analyses were performed on all variables. RESULTS: The total cost for blunt trauma patients undergoing PCT was $15,682 versus $17,673 for SCT. There was no difference in QALYs between the two populations (26.42 vs. 26.40). However, there was a cost savings of $75 per QALY for patients receiving PCT versus SCT ($594 per QALY vs. $669 per QALY). CONCLUSION: PCT enables surgeons to identify and rule out injuries promptly, thereby reducing the need for inpatient observation. The risk of RIC is low following a single PCT. This cost-utility analysis finds PCT based on mechanism to be a cost-effective use of resources. LEVEL OF EVIDENCE: Economic and value-based evaluations, level II.

Routine prophylactic central neck dissection for low-risk papillary thyroid cancer is not cost-effective.

BACKGROUND: The role of routine prophylactic central neck dissection (CND) in papillary thyroid cancer (PTC) remains controversial. The aim of this study was to evaluate the cost utility of the addition of routine CND in patients with low-risk PTC compared with total thyroidectomy (TT) alone. METHODS: A Markov model for low-risk PTC was constructed with a treatment algorithm based on the American Thyroid Association guidelines for well-differentiated thyroid carcinoma. Utilities and outcome probabilities were derived from published medical literature. US 2010 costs were examined from a society perspective using Medicare reimbursement rates and opportunity loss based on published US government data. Monte Carlo simulation and sensitivity analysis were used to examine the uncertainty of probability, cost and utility estimates. RESULTS: Initial TT alone is more cost-effective than TT with CND, resulting in a cost savings of US $5763 per patient with slightly higher effectiveness per patient (0·03 QALY) for a cost savings of $285 per QALY. Sensitivity analysis shows that TT alone offers no advantage when radioactive iodine (RAI) becomes more detrimental to a patient's state of health, when the incidence of non-neck recurrence increases above 5% in patients undergoing TT alone or decreases below 3·9% in patients undergoing TT with CND or when the rate of permanent hypocalcaemia rises above 4%. CONCLUSIONS: TT with CND is not a cost-effective strategy in low-risk PTC. Initial TT alone is favourable because of the low complication rates and low recurrence rates associated with the initial surgery. Alternative strategies such as unilateral prophylactic neck dissection require additional study to assess their cost-effectiveness.

Cost-utility analysis of prehospital spine immobilization recommendations for penetrating trauma.

BACKGROUND: The American College of Surgeons' Committee on Trauma's recent prehospital trauma life support recommendations against prehospital spine immobilization (PHSI) after penetrating trauma are based on a low incidence of unstable spine injuries after penetrating injuries. However, given the chronic and costly nature of devastating spine injuries, the cost-utility of PHSI is unclear. Our hypothesis was that the cost-utility of PHSI in penetrating trauma precludes routine use of this prevention strategy. METHODS: A Markov model based cost-utility analysis was performed from a society perspective of a hypothetical cohort of 20-year-old males presenting with penetrating trauma and transported to a US hospital. The analysis compared PHSI with observation alone. The probabilities of spine injuries, costs (US 2010 dollars), and utility of the two groups were derived from published studies and public data. Incremental effectiveness was measured in quality-adjusted life-years. Subset analyses of isolated head and neck injuries as well as sensitivity analyses were performed to assess the strength of the recommendations. RESULTS: Only 0.2% of penetrating trauma produced unstable spine injury, and only 7.4% of the patients with unstable spine injury who underwent spine stabilization had neurologic improvement. The total lifetime per-patient cost was $930,446 for the PHSI group versus $929,883 for the nonimmobilization group, with no difference in overall quality-adjusted life-years. Subset analysis demonstrated that PHSI for patients with isolated head or neck injuries provided equivocal benefit over nonimmobilization. CONCLUSION: PHSI was not cost-effective for patients with torso or extremity penetrating trauma. Despite increased incidence of unstable spine injures produced by penetrating head or neck injuries, the cost-benefit of PHSI in these patients is equivocal, and further studies may be needed before omitting PHSI in patients with penetrating head and neck injuries. LEVEL OF EVIDENCE: Economic and value-based evaluation, level II.

Emergency uncrossmatched transfusion effect on blood type alloantibodies.

BACKGROUND: Trauma patients receive emergency transfusions of unmatched Type O Rh-negative (Rh-) blood until matched blood is available. We hypothesized that patients given uncrossmatched blood may develop alloantibodies, placing them at risk for hemolytic transfusion reactions (HTRs). METHODS: Data regarding alloantibody profiles and HTR occurrence were collected from the records of trauma patients at our university-based trauma center who received emergency uncrossmatched blood from July 2008 to August 2010. RESULTS: A total of 132 patients received 1,570 units of packed red blood cells. Mean injury severity score was 28 ± 1.3. Forty-five (34%) patients died: 27 on hospital day 1; the remaining 18 had no evidence of HTR before death. Four Rh- female patients received Rh+ fresh frozen plasma, but none received Rh+ packed red blood cells. Three Rh- male patients received both Rh+ packed red blood cells and fresh frozen plasma, and one received Rh+ fresh frozen plasma. One patient developed anti-Rh D antibodies. None experienced HTR. One female patient had HTR from reactivation of anamnestic JK antibodies. Thirteen (33%) of 39 patients met criteria for HTR based on urinalysis and 29 (40%) of 72 patients tested met criteria for HTR based on hemoglobin and bilirubin values. Only one patient had confirmed HTR. CONCLUSION: High rates of injury recidivism in trauma patients increase the likelihood of multiple blood transfusions during their lifetime. Rh- patients who receive Rh+ blood are at risk of developing anti-Rh antibodies, putting them at risk for HTR. The conservation of Rh- blood for use in female patients may be detrimental to Rh- male patients. Laboratory diagnostic criteria for HTR are nonspecific in the trauma population and should be used with caution.

Single-contrast computed tomography for the triage of patients with penetrating torso trauma.

BACKGROUND: We have used single-contrast (intravenous contrast only) computed tomography (SCCT) for triaging hemodynamically stable patients with penetrating torso trauma. We hypothesized that SCCT safely determines the need for operative exploration. Furthermore, trauma surgeons without specialized training in body imaging can accurately apply this modality. METHODS: We retrospectively reviewed the records of patients with penetrating torso injuries at a university-based urban trauma center to establish the accuracy of SCCT in determining the need for exploratory laparotomy. The scan was considered positive or negative with respect to the need for exploratory laparotomy as documented by the attending surgeon, who may have considered the read of the on call radiologist if available. In a separate study, four trauma surgeons independently reviewed 42 SCCT scans to establish whether the scans alone could be used to determine whether operative exploration was necessary. RESULTS: Between 1997 and 2008, 306 hemodynamically stable patients with penetrating torso trauma were triaged by SCCT. Overall, SCCT predicted the need for laparotomy with 98% sensitivity and 90% specificity. The positive predictive value was 84% and the negative predictive value (NPV) was 99%. In the 222 patients with gunshot wounds, SCCT had 100% sensitivity and 100% NPV. In the 84 patients with stab wounds, SCCT had 92% sensitivity and 97% NPV. Trauma surgeon agreement in the retrospective review of 42 computed tomography scans was "nearly perfect": positive predictive value was 93% and NPV was 92% for determining the need for exploratory laparotomy surgery. CONCLUSIONS: SCCT is safe and effective for triaging hemodynamically stable patients with penetrating torso trauma. It successfully determined the need for operative intervention with appropriate clinical accuracy without the additional costs, morbidity, and delay of oral and rectal contrast. Trauma surgeons can reproducibly interpret SCCT with high-predictive accuracy as to whether patients with penetrating torso trauma require operative exploration.

Admission serum lactate levels do not predict mortality in the acutely injured patient.

INTRODUCTION: The conventional view that admission lactate levels predict outcome in trauma patients stems from simple comparisons of mean blood levels between groups and small sample sizes. To better address this question, we performed more rigorous statistical analyses of lactate in a larger patient sample. METHODS: We prospectively collected data on admission lactate and outcomes in 5,995 patients admitted to an urban, university-based trauma center. The ability of admission lactate to predict mortality was assessed by logistic regression, calculation of positive predictive values (PPV), and measurement of areas under receiver operating characteristic (ROC) curves. RESULTS: Differences between survivors and nonsurvivors in means of most proposed prognosticators was again demonstrated. However, the large overlap in these variables between survivors and nonsurvivors prevented clinically useful predictions. The overall PPV of elevated lactate was only 5.4%. Even in severely injured patients (Injury Severity Score >20; mortality 23%), elevated admission lactate level was a poor predictor of outcome. ROC analyses found no useful sensitivity threshold overall or after stratification by age, sex, Glasgow Coma Scale score, revised trauma score, or mechanism of injury. CONCLUSIONS: This large retrospective examination of admission lactate levels failed to show useful predictive accuracy for hospital death. Serum lactate levels need not be obtained routinely but can be reserved for patients who will be admitted to the intensive care unit and/or require an emergency operation.

Quantification of surgical resident stress "on call".

BACKGROUND: We hypothesized that surgical resident stress involves both psychologic and physiologic components that manifest as changes in heart rate (HR) and circulating white blood cell (WBC) count. The purposes of this series of experiments were to monitor HR as a measure of stress "on call"; to monitor WBC count (1,000 cells/microL) during "on call" periods as a measure of stress; and to relate maximum HR and WBC count "on call" to surgical resident training level. STUDY DESIGN: HR was continuously documented by Holter monitor for 24hours "on call" in interns (n = 6), junior residents (n = 5), and senior residents (n = 5). Interns (n = 4), junior residents (n = 4), and senior residents (n = 4) during periods devoid of clinical responsibilities served as controls. WBC counts were obtained from residents "off" and "on call" for interns (n = 5) and junior residents (n = 5). RESULTS: Mean HR "on call" increased in all resident groups as compared with controls: intern mean HR increased from 71 +/- 3 to 87 +/- 2 beats per minute (bpm) (p = 0.003), junior resident mean HR increased from 74 +/- 3 to 88 +/- 4 bpm (p = 0.03), and senior resident mean HR increased from 69 +/- 2 to 80 +/- 2 bpm (p = 0.004). Intern maximum control HR was 119 +/- 3 and increased to 149 +/- 6 bpm (p = 0.005). The increase in maximum HR (control versus "on call") did not reach significance in junior residents (123 +/- 5 to 136 +/- 6 bpm, p = 0.14) and senior residents (115 +/- 6 to 116 +/- 3 bpm, p = 0.9). WBC count in interns increased from control values of 5.2 +/- 0.6 x 1,000 cells/microL to 7.5 +/- 0.9 x 1,000 cells/microL"on call" (p = 0.005). The WBC change in juniors was not significant (control: 6.8 +/- 0.7 x 1,000 cells/microL, "on call": 7.1 +/- 0.7 x 1,000 cells/microL; p = 0.37). CONCLUSIONS: When heart rate is used as an indicator of combined physiologic and psychologic stress, surgical residents achieve stress levels of tachycardia "on call." Surgical residents also exhibit an increase in circulating WBC count "on call." Both the degree of tachycardia and the increase in WBC count are inversely related to the level of training. Senior residents cope better with stress "on call" than junior residents and interns.

Magnetic resonance cholangiography: applications in patients with calculus disease of the biliary tract.

Magnetic resonance cholangiography (MRC) is a non-invasive imaging modality that has become widely available. In the short time since its introduction, MRC has been shown to possess excellent accuracy for the diagnosis of various biliary pathologies, including choledocholithiasis. Investigations of the clinical applications of MRC are ongoing. This review summarizes the diagnostic capabilities of MRC and discusses its application in the management of patients with gallstone diseases.

Acute pancreatitis in intensive care unit patients: value of clinical and radiologic prognosticators at predicting clinical course and outcome.

OBJECTIVE: To assess the value of clinical and/or radiographic prognostic indices in predicting the clinical course and outcome of patients with acute pancreatitis, in the intensive care unit. DESIGN: Retrospective, single institution review. SETTING: An adult medical and surgical intensive care unit in a public, urban teaching hospital. PATIENTS: Patients with acute pancreatitis requiring intensive care unit admission between January 1, 1997 and June 30, 2000. INTERVENTIONS: Standard care. MEASUREMENTS AND MAIN RESULTS: A total of 477 patients were hospitalized with the diagnosis of acute pancreatitis. Of these, 28 patients (6%) were admitted to the intensive care unit. Ranson's, Imrie scores, Acute Physiologic and Chronic Health Evaluation (APACHE) II and III scores, simplified acute physiology scores, and multiple organ dysfunction scores were tabulated at 1, 2, 3, 7, and 14 days after intensive care unit admission. Abdominal computed tomography was available for review for 24 of the 28 patients (86%), where the mean Balthazar's computed tomography index was 4.5 +/- 0.4 (range = 2 to 10). Hospital mortality rate for the intensive care unit patients was 14% (4 of 28). The intensive care unit length of stay ranged from 1 to 79 days (mean 15 days, median 5 days). Fifty-seven percent of the patients developed organ dysfunction, and 36% of the patients required mechanical ventilatory support, ranging in duration from 1 to 70 days. Infectious morbidity occurred in 43% of patients. Thirty-six percent of the patients required operative intervention for intraabdominal complications. APACHE II scores at 7 days after intensive care unit admission correlated closely with ventilator days (r2 =.90; p =.003) and correlated with the occurrence of infectious complications (r2 =.71; p =.02). Patient age, APACHE III, simplified acute physiology scores, multiple organ dysfunction scores, Ranson, Imrie, computed tomography, and APACHE II scores before day 7 did not closely correlate with the occurrence of adverse clinical outcome. CONCLUSIONS: The clinical course and outcomes of intensive care unit patients with acute pancreatitis can be highly variable. An APACHE II score <10 during the initial 48 hrs correlated with mild pancreatitis and uncomplicated intensive care unit course; however, multifactorial prognosticators were not useful for the early identification of patients who developed complications or required extended intensive care unit care.

Does upregulation of inducible nitric oxide synthase play a role in hepatic injury?

Lipopolysaccharide (LPS) and gut ischemia/reperfusion (I/R) injury cause reversible liver injury. Because nitric oxide (NO) can have both beneficial and deleterious effects in the gastrointestinal tract, and because the role of NO in gut I/R-induced hepatic injury is unknown, this study examined its role in LPS and gut I/R-induced hepatic injury in the rat. Both LPS and gut I/R caused a similar increase in serum hepatocellular enzymes. LPS but not gut I/R caused a significant increase in upregulation of hepatic inducible NO synthase (iNOS) according to quantitative real-time RT-PCR and Western immunoblot analysis. Aminoguanidine, a selective iNOS inhibitor, attenuated LPS-induced hepatic injury and hypotension, but did not prevent gut I/R-induced hepatic injury. In contrast, the non-selective NOS inhibitor N(G)-nitro-L-arginine methyl ester aggravated liver damage from both LPS and gut I/R. These data indicate that iNOS plays a role in mediating LPS-induced hepatic injury, but not gut I/R-induced hepatic injury. The data also suggest that the constitutive isoforms of NOS play a hepatoprotective role in both models of hepatic injury.

Standardized patient care guidelines reduce infectious morbidity in appendectomy patients.

BACKGROUND: Surgical wound infection and intra-abdominal abscess remain common infectious complications after appendectomy, especially in the setting of a perforated or gangrenous appendix. We therefore developed a clinical protocol for the management of appendicitis to decrease postoperative infectious complications. METHODS: Between January 1, 1999, and December 31, 1999, 206 patients with appendicitis were treated on protocol. Retrospectively, the charts were reviewed for all protocol patients as well as for 232 patients with appendicitis treated in the year prior to protocol initiation. Data were collected on surgical wound infections and intra-abdominal abscesses. RESULTS: There were significantly fewer infectious complications in the protocol group than in the nonprotocol group (20 [9%] versus 8 [4%]; P <0.05). In patients with a perforated or gangrenous appendix, the infectious complication rate was reduced from 33% to 13% (P <0.05). CONCLUSIONS: The incidence of infectious complications after appendectomy can be significantly reduced with a standardized approach to antibiotic therapy and wound management.

Laparoscopic cholecystectomy for acute cholecystitis: technical considerations and outcome.

Laparoscopic cholecystectomy (LC) is the preferred method of treatment for patients with gallbladder disease in the elective setting. Despite being technically more difficult, LC performed during the early course of acute cholecystitis can be safe and cost-effective. The current review discusses the diagnostic and therapeutic strategies that may help promote the safe and successful laparoscopic treatment of patients with acute cholecystitis.