Surgical errors and the relationships of disease, risks, and adverse events.

BACKGROUND: Relationships between surgical errors and adverse events have not been fully explored and were examined in this study. MATERIALS AND METHODS: This retrospective cohort study reviewed records of deceased surgical patients over 12 months. Bivariate associations between predictors and errors were examined. RESULTS: 84 deaths occurred following 5,209 operations. Errors in care (63%) compared to those without had significantly more adverse events, (98% vs 80% respectively, p = 0.004). Significant association occurred between error and emergency status, p = 0.016); length of stay >10 days, p = 0.011; adverse events, p = 0.005). Regression results indicated number of adverse events (OR = 1.27, 95% CI (1.08-1.49), p = 0.003) and length of stay (OR = 1.05, 95% CI (1.01-1.09), p = 0.008) were associated with surgical errors. CONCLUSIONS: Examining postoperative adverse events in error cases identified opportunities for improvement. Reducing medical errors requires measuring medical errors.

Robotic compared with laparoscopic cholecystectomy: A propensity matched analysis.

BACKGROUND: As robotic surgery becomes more ubiquitous, determining clinical benefit is necessary to justify the cost and time investment required to become proficient. We hypothesized that robotic cholecystectomy would be associated with improved clinical outcomes but also increased cost as compared with standard laparoscopic cholecystectomy. MATERIALS AND METHODS: All patients undergoing robotic or laparoscopic cholecystectomy at a single academic hospital between 2007 and 2017 were identified using an institutional clinical data repository. Patients were stratified by operative approach (robotic versus laparoscopic) for comparison and propensity score matched 1:10 based on relevant comorbidities and demographics. Categorical variables were analyzed by the χ2 test and continuous variables using the Mann-Whitney U test. RESULTS: A total of 3,255 patients underwent cholecystectomy during the study period. We observed no differences in demographics or body mass index, but greater rates of diabetes mellitus, hypertension, and gastroesophageal reflux disease were present in the laparoscopic group. After matching (n = 106 robotic, n = 1,060 laparoscopic), there were no differences in preoperative comorbidities. Patients who underwent robotic cholecystectomy had lesser durations of stay (robotic: 0.1 ± 0.7 versus laparoscopic: 0.8 ± 1.9, P < .0001) and lesser 90-day readmission rates (robotic: 0% [0], laparoscopic: 4.1% [43], P = 0.035); however, both operative and hospital costs were greater compared with laparoscopic cholecystectomy. CONCLUSION: Robotic cholecystectomy is associated with lesser duration of stay and lesser readmission rate within 90 days of the index operation, but also greater operative duration and hospital cost compared with laparoscopic cholecystectomy. Hospitals and surgeons need to consider the improved clinical outcomes but also the monetary and time investment required before pursuing robotic cholecystectomy.

Inguinal hernia repair: is there a benefit to using the robot?

BACKGROUND: The number of robotic surgical procedures performed yearly is constantly rising, due to improved dexterity and visualization capabilities compared with conventional methods. We hypothesized that outcomes after robotic-assisted inguinal hernia repair would not be significantly different from outcomes after laparoscopic or open repair. METHODS: All patients undergoing inguinal hernia repair between 2012 and 2016 were identified using institutional American College of Surgeons National Surgical Quality Improvement Program data. Demographics; preoperative, intraoperative, and postoperative characteristics; and outcomes were evaluated based on method of repair (Robot, Lap, or Open). Categorical variables were analyzed by Chi-square test and continuous variables using Mann-Whitney U. RESULTS: A total of 510 patients were identified who underwent unilateral inguinal hernia repair (Robot: 13.8% [n = 69], Lap: 48.1% [n = 241], Open: 38.1% [n = 191]). There were no demographic differences between groups other than age (Robot: 52 [39-62], Lap: 57 [45-67], and Open: 56 [48-67] years, p = 0.03). Operative duration was also different (Robot: 105 [76-146] vs. Lap: 81 [61-103] vs. Open: 71 [56-88] min, p < 0.001). There were no operative mortalities and all patients except one were discharged home the same day. Postoperative occurrences (adverse events, readmissions, and death) were similar between groups (Robot: 2.9% [2], Lap: 3.3% [8], Open: 5.2% [10], p = 0.53). Although rare, there was a significant difference in rate of postoperative skin and soft tissue infection (Robot: 2.9% [2] vs. Lap: 0% [0] vs. Open: 0.5% [1], p = 0.02). Cost was significantly different between groups (Robot: $7162 [$5942-8375] vs. Lap: $4527 [$2310-6003] vs. Open: $4264 [$3277-5143], p < 0.001). CONCLUSIONS: Outcomes after robotic-assisted inguinal hernia repair were similar to outcomes after laparoscopic or open repair. Longer operative duration during robotic repair may contribute to higher rates of skin and soft tissue infection. Higher cost should be considered, along with surgeon comfort level and patient preference when deciding whether inguinal hernia repair is approached robotically.

Sex- and diagnosis-dependent differences in mortality and admission cytokine levels among patients admitted for intensive care.

OBJECTIVES: To investigate the role of sex on cytokine expression and mortality in critically ill patients. DESIGN: A cohort of patients admitted to were enrolled and followed over a 5-year period. SETTING: Two university-affiliated hospital surgical and trauma ICUs. PATIENTS: Patients 18 years old and older admitted for at least 48 hours to the surgical or trauma ICU. INTERVENTIONS: Observation only. MEASUREMENTS AND MAIN RESULTS: Major outcomes included admission cytokine levels, prevalence of ICU-acquired infection, and mortality during hospitalization conditioned on trauma status and sex. The final cohort included 2,291 patients (1,407 trauma and 884 nontrauma). The prevalence of ICU-acquired infection was similar for men (46.5%) and women (44.5%). All-cause in-hospital mortality was 12.7% for trauma male patient and 9.1% for trauma female patient (p = 0.065) and 22.9% for nontrauma male patients and 20.6% for nontrauma female patients (p = 0.40). Among trauma patients, logistic regression analysis identified female sex as protective for all-cause mortality (odds ratio, 0.57). Among trauma patients, men had significantly higher admission serum levels of interleukin-2, interleukin-12, interferon-γ, and tumor necrosis factor-α, and among nontrauma patients, men had higher admission levels of interleukin-8 and tumor necrosis factor-α. CONCLUSIONS: The relationship between sex and outcomes in critically ill patients is complex and depends on underlying illness. Women appear to be better adapted to survive traumatic events, while sex may be less important in other forms of critical illness. The mechanisms accounting for this gender dimorphism may, in part, involve differential cytokine responses to injury, with men expressing a more robust proinflammatory profile.

Differences in morbidity and mortality with percutaneous versus open surgical drainage of postoperative intra-abdominal infections: a review of 686 cases.

Intra-abdominal infections following surgical procedures result from organ-space surgical site infections, visceral perforations, or anastomotic leaks. We hypothesized that open surgical drainage is associated with increased patient morbidity and mortality compared with percutaneous drainage. A single-institution, prospectively collected database over a 13-year period revealed 2776 intra-abdominal infections, 686 of which required an intervention after the index operation. Percutaneous procedures (simple aspiration or catheter placement) were compared with all other open procedures by univariate and multivariate analyses. Analysis revealed 327 infections in 240 patients undergoing open surgical drainage and 359 infections in 260 patients receiving percutaneous drainage. Those undergoing open drainage had significantly higher Acute Physiology Score (APS) and Acute Physiology and Chronic Health Evaluation (APACHE) II scores and were more likely to be immunosuppressed, require intensive care unit treatment, and have longer hospital stays. Mortality was higher in the open group: 14.6 versus 4.2 per cent (P = 0.0001). Variables independently associated with death by multivariate analysis were APACHE II, dialysis, intensive care unit (ICU) care, age, immunosuppression, and drainage method. Open intervention for postsurgical intra-abdominal infections is associated with increased mortality compared with percutaneous drainage even after controlling for severity of illness by multivariate analysis. Although some patients are not candidates for percutaneous drainage, it should be considered the preferential treatment in eligible patients.

Does preoperative ejection fraction predict operative mortality with left ventricular restoration?

BACKGROUND: Ischemic cardiomyopathy and aneurysmal disease have been treated surgically with coronary artery bypass grafting in the past. The Dor technique for left ventricular restoration has demonstrated improved outcomes in patients with ischemic, akinetic ventricles. Our hypothesis was that even marked reduction in preoperative cardiac function (ejection fraction < .25) would not correlate with worse outcomes since the ventricle would be reshaped to improve function. METHODS: A retrospective analysis was performed on all patients who had undergone ventricular restoration with the Dor procedure from January 1996 through September 2005. Patients with a preoperative ejection fraction (EF) < .25 and those with a EF > or = .25 were compared. All Society of Thoracic Surgeons database characteristics, mortality, length of stay (LOS), and need for intraaortic balloon pump (IABP) were analyzed. RESULTS: The study included 89 patients (69 men, 20 women), 28 of whom had preoperative EFs < .25 (mean, .183 +/- .035; range, .08 to .25) and 61 had an EF > or = .25 (mean, .334 +/- .074; mean, .25 to .45). Overall operative mortality was 3.4% (3/89), with no statistically significant difference between the two groups (3.6% versus 3.3%). LOS was 7.4 +/- 3.6 days versus 8.9 +/- 15.6 days (p = NS), and need for IABP was 39.2% versus 8.1% (p < 0.05). Overall 5-year survival was 82%. Five-year survival in the EF < .25 cohort was 69.6% versus 88.3% in the EF > or = .25 cohort (p = 0.066). CONCLUSIONS: Ventricular restoration with the Dor technique is a safe procedure. Marked reduction in ejection fraction is not a contraindication to left ventricular restoration; however, increased usage of IABP should be anticipated.

Functional and cytoarchitectural spinal cord protection by ATL-146e after ischemia/reperfusion is mediated by adenosine receptor agonism.

BACKGROUND: ATL-146e protects the spinal cord from ischemia/reperfusion injury, presumably via adenosine A(2A) receptor activation, but this relationship remains unproven. We hypothesized that spinal cord functional and cytoarchitectural preservation from ATL-146e would be lost with simultaneous administration of the specific adenosine A(2A) antagonist ZM241385 (ZM), thus proving that adenosine A(2A) receptor activation is responsible for the protective effects of this compound. METHODS: New Zealand White rabbits underwent 45 minutes of infrarenal aortic cross-clamping. Groups (n = 10) included sham, ischemia, ischemia plus ATL-146e (ATL-146E), ischemia plus ZM, or ischemia with both compounds (agonist-antagonist). Tarlov scores were recorded every 12 hours. After 48 hours, the spinal cord was fixed for histology and microtubule-associated protein 2 immunohistochemistry. RESULTS: Tarlov scores at 48 hours were significantly better in the sham and ATL-146E groups (5.0 and 3.9, respectively) compared with the other three groups (all < or =1.3; P < .001). On hematoxylin and eosin, neuronal viability was higher in the sham, ATL-146E, and agonist-antagonist groups compared with the control and ZM groups (P < .05). Microtubule-associated protein 2 expression was preserved in the sham and ATL-146E groups but was lost in the ATL + ZM, ZM241385, and control groups. CONCLUSIONS: ATL-146e preserves the spinal cord in terms of both cytoarchitecture and function after reperfusion of the ischemic spinal cord, but this preservation is not completely blocked by competitive adenosine A(2A) receptor antagonism. Although ATL-146e does seem to partially function through activation of the adenosine A(2A) receptor, the neuroprotective mechanism may not be limited to this particular receptor.

Comparison of systemic and retrograde delivery of adenosine A2A agonist for attenuation of spinal cord injury after thoracic aortic cross-clamping.

BACKGROUND: Paraplegia remains a devastating complication of thoracic aortic surgery, which has been attenuated by retrograde adenosine and systemic adenosine A2A receptor activation. We hypothesized that despite retrograde spinal perfusion of an adenosine A2A agonist (ATL-146e), systemic therapy produces superior spinal cord protection with reduced inflammation. METHODS: Forty pigs underwent 30-minute thoracic aortic cross-clamping. Pigs received: no therapy (control); retrograde saline (retrograde control); retrograde ATL-146e; systemic ATL-146e; systemic ATL-146e with retrograde saline; or systemic and retrograde ATL-146e. Retrograde therapies were given during ischemia. Systemic ATL-146e (0.06 microg.kg(-1).min(-1)) was given intravenously for 3 hours at reperfusion. At 24 hours, motor function was assessed using the Tarlov scale. Tissue was analyzed for neuronal viability, microtubule-associated protein-2 expression, and neutrophil sequestration (myeloperoxidase activity). RESULTS: Four pigs received retrograde barium showing both radiographic and histologic spinal cord perfusion. Tarlov scores at 24 hours were significantly improved versus both control groups in all ATL groups except the combined ATL-146e group (all p < 0.05). Neuronal viability by hematoxylin and eosin stain was significantly preserved in systemic ATL groups compared with both control groups (all p < 0.05). Microtubule-associated protein-2 expression was significantly preserved compared with both control groups in all systemic ATL groups. Systemic ATL significantly lowered myeloperoxidase activity versus both control groups (p < 0.01). CONCLUSIONS: Both retrograde and systemic ATL-146e therapies attenuate ischemic spinal cord injury, but combining the two routes was less effective. Given comparable results between the two routes and the simplicity of systemic delivery, peripheral venous ATL-146e at reperfusion should be preferred for spinal cord protection in thoracic aortic surgery.

Hyperoxic ventilation exacerbates lung reperfusion injury.

OBJECTIVE: It is well known that hyperoxia can be potentially harmful to the ventilated patient, although little is known about the potential effects in the setting of lung reperfusion. We hypothesized that hyperoxic ventilation at the time of reperfusion could worsen the effects of lung reperfusion injury. METHODS: Using an ex vivo, blood perfused, isolated rabbit lung system, we evaluated the effects of hyperoxic (fraction of inspired oxygen = 100%, n = 10) versus normoxic (room air, n = 10) ventilation after 18 hours of cold ischemia. Lungs were ventilated and perfused for 2 hours. A control group was immediately perfused and ventilated with a fraction of inspired oxygen of 100%. RESULTS: Lung wet/dry ratios demonstrated lower tissue edema in the normoxic group compared with in the hyperoxic group (6.72 +/- 0.89 vs 7.62 +/- 1.14 [mean +/- standard error of the mean], P = .04). Lung ventilation was also significantly better in the normoxic group versus the hyperoxic group (PCO2 = 28.96 +/- 2.01 vs 36.68 +/- 3.20 mm Hg, P = .04). Conversely, lung oxygenation after 2 hours of reperfusion (normoxic group ventilated for the last 15 minutes on 100% fraction of inspired oxygen) was not significantly different between groups (PO2 = 590.2 +/- 50.1 vs 499.6 +/- 67.5 mm Hg, P = .25). CONCLUSIONS: Ventilating lungs with 100% fraction of inspired oxygen at the time of reperfusion could increase the risk of lung reperfusion injury at the time of transplantation. Thus the patient should be ventilated with as low a fraction of inspired oxygen as possible to achieve adequate oxygen saturations during this critical reperfusion period.

Acute sleep deprivation in the thoracic surgical resident does not affect operative outcomes.

BACKGROUND: There is an increasing trend toward work hour restrictions for doctors world wide. These reforms have been inspired, in part, by the assertion by some that the fatigued physician is more prone to making errors. Interestingly, there is very little in the way of objective data with regard to the effects of sleep deprivation on patient outcomes. We have recently studied this in attending surgeons. The present study focused on thoracic surgical residents. Our hypothesis was that acute sleep deprivation would not lead to an increase in operative times or complications. METHODS: A retrospective review of all cases performed by thoracic surgical residents at the University of Virginia from January 1994 to March of 2004 was done. Complication rates of cases performed by "sleep deprived" (SD) residents were compared with cases done when the residents were "not sleep deprived" (NSD). A resident was deemed sleep deprived if he or she performed a case the previous evening that started between 10 pm and 5 am or ended between the hours of 11 pm and 7:30 am. RESULTS: A total of 7,323 cases were recorded in the STS database over the 10-year period examined. Two hundred and twenty-nine of these cases (3%) were performed by SD residents. Mortality rates for coronary artery bypass operations showed no significant differences (2.1% [SD = 3 of 141 patients] vs 3.1% (NSD = 143 of 4452 patients), p = 0.63). A comparison of operative, neurologic, renal, infectious, and pulmonary complications as well as cardiopulmonary bypass times, cross-clamp times, the use of blood products, and length of stay also demonstrated no significant differences between groups. CONCLUSIONS: Acute sleep deprivation in thoracic surgical residents does not affect operative efficiency, morbidity, or mortality in cardiac surgical operations.

Evaluation of an absorbable cyanoacrylate adhesive as a suture line sealant.

BACKGROUND: Previous formulations of cyanoacrylate, though very effective, proved to have too high a tissue reactivity to be used internally. A novel cyanoacrylate compound with less tissue reactivity was recently developed. The objective of this study was to assess this novel cyanoacrylate compound for the use as vascular suture line sealant. MATERIALS AND METHODS: Twelve adult female sheep received a 6 mm PTFE interposition graft in each iliac artery, for a total of 24 grafts. Using oxidized cellulose (Surgicel) as a control, two formulations of a new cyanoacrylate compound (named "compound A" and "compound B") were assessed during this trial. Hemostatic efficiency was measured at the time of operation by the assessment of bleeding time and amount of blood loss. Long-term graft patency was assessed angiographically at 4, 6, and 18 months. Tissue reaction at 2 weeks, 1, 6, and 18 months was assessed grossly by vascular surgeons and microscopically by a blinded pathologist. RESULTS: Average time to hemostasis was 37.6, 50.6, and 219 s in group A, group B, and oxidized cellulose control groups, respectively (P

Sleep deprivation does not affect operative results in cardiac surgery.

BACKGROUND: There has been an increasing trend towards the mandatory reduction in work hours for physicians because of the fear that sleep-deprived (SD) surgeons are more prone to make mistakes. We hypothesized that sleep deprivation would not be associated with increased morbidity or mortality in cardiac operations. METHODS: A retrospective review was done of all cases performed by all attending cardiac surgeons from January 1994 to April 2003. Complication rates of cases performed by SD surgeons were compared with cases done when the surgeons were not sleep-deprived (NSD). A surgeon was deemed sleep deprived if he or she performed a case the previous evening that started between 10:00 pm and 5:00 am, or ended between the hours of 11:00 pm and 7:30 am. RESULTS: A total of 6,751 cases were recorded in the Society of Thoracic Surgeons database over the 9-year period examined. Of these, 339 cases (5%) were performed by SD surgeons, and 6,412 (95%) cases were performed by NSD surgeons. Mortality rates for coronary artery bypass operations showed no significant differences (1.7% [SD = 4/223] vs 3.1% [NSD = 133/4206)] p = 0.34). Operative (p = 0.47), pulmonary (p = 0.60), renal (p = 0.93), neurologic (p = 0.11), and infectious (p = 0.87) complications of all cases also failed to show any statistically significant differences in any group. Perfusion times, cross-clamp times, and the use of blood products were also similar between groups. CONCLUSIONS: Sleep deprivation does not affect operative morbidity or mortality in cardiac surgical operations. These data do not support a need for work hour restrictions on surgeons.