A noninvasive postoperative clinical score to identify patients at risk for postoperative pulmonary complications: the Air-Test Score.

BACKGROUND: Postoperative pulmonary complications (PPCs) negatively affect morbidity, healthcare costs and postsurgical survival. Preoperative and intraoperative peripheral oxyhemoglobin saturation (SpO2) levels are independent risk factors for postoperative pulmonary complications (PPCs). The air-test assesses the value of SpO2 while breathing room-air. We aimed at building a clinical score that includes the air-test for predicting the risk for PPCs. METHODS: This is a development and validation study in patients -randomly divided into two cohorts- from a large randomized clinical trial (iPROVE) that enrolled 964 intermediate-to-high risk patients scheduled for abdominal surgery. Arterial oxygenation was assessed on room-air in the preoperative period (preoperative air-test) and 3h after admission to the postoperative care unit (postoperative air-test). The air-test was defined as positive or negative if SpO2 was ≤96% or >96%, respectively. Positive air-tests were stratified into weak (93-96%) or strong (<93%). The primary outcome was a composite of moderate-to-severe PPCs during the first seven postoperative days. RESULTS: A total of 902 patients were included in the final analysis (542 in the development cohort and 360 in the validation cohort). Regression analysis identified five independent risk factors for PPC: age, type of surgery, pre- and postoperative air-test, and atelectasis. The area under the receiver operating characteristic curve (AUC) was 0.79 (95% CI: 0.75-0.82) when including these five independent predictors. We built a simplified score termed "air-test score" by using only the pre- and postoperative SpO2, resulting in an AUC of 0.72 (95% CI: 0.67-0.76) for the derivation and 0.72 (95% CI: 0.66-0.78) for the validation cohort, respectively. The air-test score stratified patients into four levels of risk, with PPCs ranging from <15% to >75%. CONCLUSIONS: The simple, non-invasive and inexpensive bedside air-test score, evaluating pre- and postoperatively SpO2 measured on room-air, helps to predict the risk for PPCs.

Effects of oxygen on post-surgical infections during an individualised perioperative open-lung ventilatory strategy: a randomised controlled trial.

BACKGROUND: We aimed to examine whether using a high fraction of inspired oxygen (FIO2) in the context of an individualised intra- and postoperative open-lung ventilation approach could decrease surgical site infection (SSI) in patients scheduled for abdominal surgery. METHODS: We performed a multicentre, randomised controlled clinical trial in a network of 21 university hospitals from June 6, 2017 to July 19, 2018. Patients undergoing abdominal surgery were randomly assigned to receive a high (0.80) or conventional (0.3) FIO2 during the intraoperative period and during the first 3 postoperative hours. All patients were mechanically ventilated with an open-lung strategy, which included recruitment manoeuvres and individualised positive end-expiratory pressure for the best respiratory-system compliance, and individualised continuous postoperative airway pressure for adequate peripheral oxyhaemoglobin saturation. The primary outcome was the prevalence of SSI within the first 7 postoperative days. The secondary outcomes were composites of systemic complications, length of intensive care and hospital stay, and 6-month mortality. RESULTS: We enrolled 740 subjects: 371 in the high FIO2 group and 369 in the low FIO2 group. Data from 717 subjects were available for final analysis. The rate of SSI during the first postoperative week did not differ between high (8.9%) and low (9.4%) FIO2 groups (relative risk [RR]: 0.94; 95% confidence interval [CI]: 0.59-1.50; P=0.90]). Secondary outcomes, such as atelectasis (7.7% vs 9.8%; RR: 0.77; 95% CI: 0.48-1.25; P=0.38) and myocardial ischaemia (0.6% [n=2] vs 0% [n=0]; P=0.47) did not differ between groups. CONCLUSIONS: An oxygenation strategy using high FIO2 compared with conventional FIO2 did not reduce postoperative SSIs in abdominal surgery. No differences in secondary outcomes or adverse events were found. CLINICAL TRIAL REGISTRATION: NCT02776046.

Computerized tests to evaluate recovery of cognitive function after deep sedation with propofol and remifentanil for colonoscopy.

The use of sedation for diagnostic procedures including gastrointestinal endoscopy is rapidly growing. Recovery of cognitive function after sedation is important because it would be important for most patients to resume safe, normal life soon after the procedure. Computerized tests have shown being accurate descriptors of cognitive function. The purpose of the present study was to evaluate the time course of cognitive function recovery after sedation with propofol and remifentanil. A prospective observational double blind clinical study conducted in 34 young healthy adults undergoing elective outpatient colonoscopy under sedation with the combination of propofol and remifentanil using a target controlled infusion system. Cognitive function was measured using a validated battery of computerized cognitive tests (Cogstate™, Melbourne, Australia) at different predefined times: prior to starting sedation (Tbaseline), and then 10 min (T10), 40 min (T40) and 120 min (T120) after the end of colonoscopy. Tests included the assessment of psychomotor function, attention, visual memory and working memory. All colonoscopies were completed (median time: 26 min) without significant adverse events. Patients received a median total dose of propofol and remifentanil of 149 mg and 98 µg, respectively. Psychomotor function and attention declined at T10 but were back to baseline values at T40 for all patients. The magnitude of psychomotor task reduction was large (d = 0.81) however 100% of patients were recovered at T40. Memory related tasks were not affected 10 min after ending sedation. Cognitive impairment in attention and psychomotor function after propofol and remifentanil sedation was significant and large and could be easily detected by computerized cognitive tests. Even though, patients were fully recovered 40 min after ending the procedure. From a cognitive recovery point of view, larger studies should be undertaken to propose adequate criteria for discharge after sedation.

Individualised perioperative open-lung approach versus standard protective ventilation in abdominal surgery (iPROVE): a randomised controlled trial.

BACKGROUND: The effects of individualised perioperative lung-protective ventilation (based on the open-lung approach [OLA]) on postoperative complications is unknown. We aimed to investigate the effects of intraoperative and postoperative ventilatory management in patients scheduled for abdominal surgery, compared with standard protective ventilation. METHODS: We did this prospective, multicentre, randomised controlled trial in 21 teaching hospitals in Spain. We enrolled patients who were aged 18 years or older, were scheduled to have abdominal surgery with an expected time of longer than 2 h, had intermediate-to-high-risk of developing postoperative pulmonary complications, and who had a body-mass index less than 35 kg/m2. Patients were randomly assigned (1:1:1:1) online to receive one of four lung-protective ventilation strategies using low tidal volume plus positive end-expiratory pressure (PEEP): open-lung approach (OLA)-iCPAP (individualised intraoperative ventilation [individualised PEEP after a lung recruitment manoeuvre] plus individualised postoperative continuous positive airway pressure [CPAP]), OLA-CPAP (intraoperative individualised ventilation plus postoperative CPAP), STD-CPAP (standard intraoperative ventilation plus postoperative CPAP), or STD-O2 (standard intraoperative ventilation plus standard postoperative oxygen therapy). Patients were masked to treatment allocation. Investigators were not masked in the operating and postoperative rooms; after 24 h, data were given to a second investigator who was masked to allocations. The primary outcome was a composite of pulmonary and systemic complications during the first 7 postoperative days. We did the primary analysis using the modified intention-to-treat population. This trial is registered with ClinicalTrials.gov, number NCT02158923. FINDINGS: Between Jan 2, 2015, and May 18, 2016, we enrolled 1012 eligible patients. Data were available for 967 patients, whom we included in the final analysis. Risk of pulmonary and systemic complications did not differ for patients in OLA-iCPAP (110 [46%] of 241, relative risk 0·89 [95% CI 0·74-1·07; p=0·25]), OLA-CPAP (111 [47%] of 238, 0·91 [0·76-1·09; p=0·35]), or STD-CPAP groups (118 [48%] of 244, 0·95 [0·80-1·14; p=0·65]) when compared with patients in the STD-O2 group (125 [51%] of 244). Intraoperatively, PEEP was increased in 69 (14%) of patients in the standard perioperative ventilation groups because of hypoxaemia, and no patients from either of the OLA groups required rescue manoeuvres. INTERPRETATION: In patients who have major abdominal surgery, the different perioperative open lung approaches tested in this study did not reduce the risk of postoperative complications when compared with standard lung-protective mechanical ventilation. FUNDING: Instituto de Salud Carlos III of the Spanish Ministry of Economy and Competitiveness, and Grants Programme of the European Society of Anaesthesiology.

Personalised Prehabilitation in High-risk Patients Undergoing Elective Major Abdominal Surgery: A Randomized Blinded Controlled Trial.

OBJECTIVE: The aim of this study was to assess the impact of personalized prehabilitation on postoperative complications in high-risk patients undergoing elective major abdominal surgery. SUMMARY BACKGROUND DATA: Prehabilitation, including endurance exercise training and promotion of physical activity, in patients undergoing major abdominal surgery has been postulated as an effective preventive intervention to reduce postoperative complications. However, the existing studies provide controversial results and show a clear bias toward low-risk patients. METHODS: This was a randomized blinded controlled trial. Eligible candidates accepting to participate were blindly randomized (1:1 ratio) to control (standard care) or intervention (standard care + prehabilitation) groups. Inclusion criteria were: i) age >70 years; and/or, ii) American Society of Anesthesiologists score III/IV. Prehabilitation covered 3 actions: i) motivational interview; ii) high-intensity endurance training; and promotion of physical activity. The main study outcome was the proportion of patients suffering postoperative complications. Secondary outcomes included the endurance time (ET) during cycle-ergometer exercise. RESULTS: We randomized 71 patients to the control arm and 73 to intervention. After excluding 19 patients because of changes in the surgical plan, 63 controls and 62 intervention patients were included in the intention-to-treat analysis. The intervention group enhanced aerobic capacity [ΔET 135 (218) %; P < 0.001), reduced the number of patients with postoperative complications by 51% (relative risk 0.5; 95% confidence interval, 0.3-0.8; P = 0.001) and the rate of complications [1.4 (1.6) and 0.5 (1.0) (P =  0.001)] as compared with controls. CONCLUSION: Prehabilitation enhanced postoperative clinical outcomes in high-risk candidates for elective major abdominal surgery, which can be explained by the increased aerobic capacity.

Prediction of thromboembolic complications after liver resection for cholangiocarcinoma: is there a place for thromboelastometry?

: Postoperative venous thromboembolism has a poor prognosis in patients with cancer. We aimed to investigate the utility of thromboelastometry in detecting the risk of postoperative venous thromboembolism in patients with cholangiocarcinoma. We prospectively included patients submitted to liver resection for cholangiocarcinoma at our hospital between May 2011 and July 2014. Patients undergoing major hepatectomy for adult living donor transplantation in the same time period served as a control group. Thromboelastometry was performed before anesthesia. Postoperative venous thrombotic events were recorded in the 6 months after surgery. Twenty-seven patients with cholangiocarcinoma and 17 living-donor liver transplantation patients were included. Maximum clot firmness and its derivative parameter G, pointed to hypercoagulability in patients with cholangiocarcinoma, whereas all parameters were within normal ranges in controls. Six postoperative thrombotic events were recorded: four portal vein thrombosis and two deep venous thrombosis, all in patients with cholangiocarcinoma. Patients with cholangiocarcinoma who displayed thrombotic complications showed a nonsignificant trend to more pronounced hypercoagulability compared with those without. The results suggest that first, in patients with cholangiocarcinoma, despite standard thromboprophylaxis, thrombotic events remain a substantial problem, and, second, thromboelastometry may be useful in identifying patients with cholangiocarcinoma at risk of postoperative venous thromboembolism. Large prospective studies are warranted to confirm these results.

Rationale and study design for an individualised perioperative open-lung ventilatory strategy with a high versus conventional inspiratory oxygen fraction (iPROVE-O2) and its effects on surgical site infection: study protocol for a randomised controlled trial.

INTRODUCTION: Surgical site infection (SSI) is a serious postoperative complication that increases morbidity and healthcare costs. SSIs tend to increase as the partial pressure of tissue oxygen decreases: previous trials have focused on trying to reduce them by comparing high versus conventional inspiratory oxygen fractions (FIO2) in the perioperative period but did not use a protocolised ventilatory strategy. The open-lung ventilatory approach restores functional lung volume and improves gas exchange, and therefore it may increase the partial pressure of tissue oxygen for a given FIO2. The trial presented here aims to compare the efficacy of high versus conventional FIO2 in reducing the overall incidence of SSIs in patients by implementing a protocolised and individualised global approach to perioperative open-lung ventilation. METHODS AND ANALYSIS: This is a comparative, prospective, multicentre, randomised and controlled two-arm trial that will include 756 patients scheduled for abdominal surgery. The patients will be randomised into two groups: (1) a high FIO2 group (80% oxygen; FIO2 of 0.80) and (2) a conventional FIO2 group (30% oxygen; FIO2 of 0.30). Each group will be assessed intra- and postoperatively. The primary outcome is the appearance of postoperative SSI complications. Secondary outcomes are the appearance of systemic and pulmonary complications. ETHICS AND DISSEMINATION: The iPROVE-O2 trial has been approved by the Ethics Review Board at the reference centre (the Hospital Clínico Universitario in Valencia). Informed consent will be obtained from all patients before their participation. If the approach using high FIO2 during individualised open-lung ventilation decreases SSIs, use of this method will become standard practice for patients scheduled for future abdominal surgery. Publication of the results is anticipated in early 2019. TRIAL REGISTRATION NUMBER: NCT02776046; Pre-results.

Effects of alfapump™ system on kidney and circulatory function in patients with cirrhosis and refractory ascites.

The alfapump system has been proposed as a new treatment for the management of refractory ascites. The system removes ascites from the peritoneal cavity to urinary bladder, producing a continuous low-volume paracentesis. The aim of the study is to investigate the effects of treatment with the alfapump™ system on kidney and circulatory function in patients with cirrhosis and refractory ascites. This was a prospective study including 10 patients with cirrhosis and refractory ascites. Primary outcomes were changes in glomerular filtration rate (GFR), as assessed by isotopic techniques, and changes in circulatory function assessed by arterial pressure, cardiac output, and activity of vasoconstrictor systems. Secondary outcomes were the need for large-volume paracentesis and adverse events. Follow-up was 1 year. GFR decreased significantly from 67 mL/minute/1.73 m2 (41-90 mL/minute/1.73 m2 ) at baseline to 45 mL/minute/1.73 m2 (36-74 mL/minute/1.73 m2 ) at month 6 (P = 0.04). Mean arterial pressure and cardiac output did not change significantly; however, there was a marked increase in plasma renin activity and norepinephrine concentration (median percent increase with respect to baseline +191% and 59%, respectively). There were 68 episodes of complications of cirrhosis in 8 patients during follow-up, the most frequent being acute kidney injury. In conclusion, treatment with alfapump™ system was associated with marked activation of endogenous vasoconstrictor systems and impairment of kidney function. The chronological relationship observed between kidney impairment and vasoconstrictor systems activation after device insertion suggests a cause-effect relationship, raising the possibility that treatment with alfapump impairs effective arterial blood volume mimicking a postparacentesis circulatory dysfunction syndrome. In this context, the potential role of albumin in counteracting these effects should be investigated in future studies. Liver Transplantation 23 583-593 2017 AASLD.

Endoscopic tattooing of early colon carcinoma enhances detection of lymph nodes most prone to harbor tumor burden.

BACKGROUND: Colorectal cancer (CRC) screening programs result in the detection of early-stage asymptomatic carcinomas suitable to be surgically cured. Lymph nodes (LN) from early CRC are usually small and may be difficult to collect. Still, at least 12 LNs should be analyzed from colectomies, to ensure a reliable pN0 stage. Presurgical endoscopic tattooing improves LN procurement. In addition, molecular detection of occult LN tumor burden in histologically pN0 CRC patients is associated with a decreased survival rate. We aimed to study the impact of presurgical endoscopic tattooing on the molecular detection of LN tumor burden in early colon neoplasms. METHODS: A prospective cohort study from a CRC screening-based population was performed at a tertiary academic hospital. LNs from colectomies with and without preoperative endoscopic tattooing were assessed by two methods, hematoxylin and eosin (HE), and RT-LAMP, to detect tumor cytokeratin 19 (CK19) mRNA. We compared the amount of tumor burden and LN yields from tattooed and non-tattooed specimens. RESULTS: HE and RT-LAMP analyses of 936 LNs were performed from 71 colectomies containing early carcinomas and endoscopically unresectable adenomas (8 pT0, 17 pTis, 27 pT1, 19 pT2); 47 out of 71 (66.2 %) were tattooed. Molecular positivity correlated with the presence of tattoo in LN [p < 0.001; OR 3.1 (95 % CI 1.7-5.5)]. A significantly higher number of LNs were obtained in tattooed specimens (median 17 LN vs. 14.5 LN; p = 0.019). CONCLUSIONS: Endoscopic tattooing enables the analysis of those LNs most prone to harbor tumor cells and improves the number of LN harvested.

Reliability of thromboelastometry for detecting the safe coagulation threshold in patients taking acenocoumarol after elective heart valve replacement.

BACKGROUND: Reversal of anticoagulation can be needed in patients undergoing heart valve surgery. ROTEM® has been correlated with international normalized ratio (INR) in patients on warfarin but not with patients on acenocoumarol. This study investigates the reliability of ROTEM® for detecting INR values below the 1.5 threshold in patients on acenocoumarol therapy. MATERIAL AND METHODS: Patients on oral anticoagulation with acenocoumarol after elective heart valve replacement were prospectively included in the study. INR and the ROTEM® were measured simultaneously. ROTEM® parameters included coagulation time, clot formation time, alpha angle, and maximal clot firmness after tissue factor activation (EXTEM). Concordance between INR and ROTEM® was analyzed by Lin's concordance coefficient (LCC) and the correlation with Spearman's rho. RESULTS: Fifty-four consecutive patients (40 female; median age 67years) were included. Clotting time (CT) was the parameter that best correlated with INR (r=0.81, p<0,001), and LCC was substantial (0.67). CT was able to predict INR values above or below 1.5: area under curve=0.998. CT≥84seconds, corresponding to a cut-off for likelihood ratio (LR+)=5, had a sensitivity and specificity of 100% and 80%, respectively, to detect an INR below 1.5. For the same INR threshold, CT≥84seconds had a predictive positive value of 92.9% and a predictive negative value of 100%. CONCLUSION: Our preliminary results suggest that CT≥84seconds in the EXTEM ROTEM® test is a feasible method for predicting an insufficient reversion of oral anticoagulant therapy in patients taking acenocoumarol after elective heart valve surgery.

Transient hyperglycemia during liver transplantation does not affect the early graft function.

UNLABELLED: Background and rationale for the study. Hyperglycemia after graft reperfusion is a consistent finding in liver transplantation (LT) that remains poorly studied. We aim to describe its appearance in LT recipients of different types of grafts and its relation to the graft function. MATERIAL & METHODS: 436 LT recipients of donors after brain death (DBD), donors after cardiac death (DCD), and familial amyloidotic polyneuropathy (FAP) donors were reviewed. Serum glucose was measured at baseline, during the anhepatic phase, after graft reperfusion, and at the end of surgery. Early graft dysfunction (EAD) was assessed by Olthoff criteria. Caspase-3, IFN-γ, IL1ß, and IL6 gene expression were measured in liver biopsy. RESULTS: The highest increase in glucose levels after reperfusion was observed in FAP LT recipients and the lowest in DCD LT recipients. Glucose level during the anhepatic phase was the only modifiable predictive variable of hyperglycemia after reperfusion. No relation was found between hyperglycemia after reperfusion and EAD. However, recipients with the highest glucose levels after reperfusion tended to achieve the best glucose control at the end of surgery and those who were unable to control the glucose value after reperfusion showed EAD more frequently. The highest levels of caspase-3 were found in recipients with the lowest glucose values after reperfusion. In conclusion, glucose levels increased after graft reperfusion to a different extent according to the donor type. Contrary to general belief, transient hyperglycemia after reperfusion does not appear to impact negatively on the liver graft function and could even be suggested as a marker of graft quality.

Rationale and study design for an individualized perioperative open lung ventilatory strategy (iPROVE): study protocol for a randomized controlled trial.

BACKGROUND: Postoperative pulmonary and non-pulmonary complications are common problems that increase morbidity and mortality in surgical patients, even though the incidence has decreased with the increased use of protective lung ventilation strategies. Previous trials have focused on standard strategies in the intraoperative or postoperative period, but without personalizing these strategies to suit the needs of each individual patient and without considering both these periods as a global perioperative lung-protective approach. The trial presented here aims at comparing postoperative complications when using an individualized ventilatory management strategy in the intraoperative and immediate postoperative periods with those when using a standard protective ventilation strategy in patients scheduled for major abdominal surgery. METHODS: This is a comparative, prospective, multicenter, randomized, and controlled, four-arm trial that will include 1012 patients with an intermediate or high risk for postoperative pulmonary complications. The patients will be divided into four groups: (1) individualized perioperative group: intra- and postoperative individualized strategy; (2) intraoperative individualized strategy + postoperative continuous positive airway pressure (CPAP); (3) intraoperative standard ventilation + postoperative CPAP; (4) intra- and postoperative standard strategy (conventional strategy). The primary outcome is a composite analysis of postoperative complications. DISCUSSION: The Individualized Perioperative Open-lung Ventilatory Strategy (iPROVE) is the first multicenter, randomized, and controlled trial to investigate whether an individualized perioperative approach prevents postoperative pulmonary complications. TRIAL REGISTRATION: Registered on 5 June 2014 with identification no. NCT02158923 .

Accuracy of Vigileo/Flotrac monitoring system in morbidly obese patients.

PURPOSE: Our goal was to assess the accuracy of measuring cardiac output (CO) by the FloTrac/Vigileo (CO(V)) device in comparison with thermodilution technique through pulmonary artery catheterization (PAC(TD)) in morbidly obese patients. MATERIAL AND METHODS: Cardiac output in 8 morbidly obese patients was assessed twice at upright and lying position breathing ambient air. At least 4 consecutive CO measurements with 10 mL of ice-cold saline injections were performed each time. Simultaneous CO measurements were recorded with both single-bolus thermodilution and CO(V). RESULTS: One hundred thirty-two CO data pairs were collected. The overall mean single-bolus thermodilution 6.2 ± 1.1 L/min was lower than the overall mean CO(V) 7.8 ± 1.6 L/min (P < .001). Lin concordance coefficient indicated that overall agreement between PAC(TD) and CO(V) was poor, 0.29. Lin concordance coefficient in sitting position was 0.29, 95% confidence interval (0.17-0.40) and in lying position was 0.30, 95% confidence interval (0.15-0.44). The Bland-Altman plot analysis showed systematically higher values from CO(V) in comparison with PAC(TD). These differences increased in presence of high CO measurements. In 3 of 8 patients, the percentage error was lower than 20%, whereas in the other 5, it was higher than 20%. Of these 5, in 2 cases, the percentage error was greater than 50%. CONCLUSION: Data obtained using CO(V) vs PAC(TD) measurements showed poor correlation. The results were not interchangeable.

Minimal invasive surgery: NOSE and NOTES in ulcerative colitis.

BACKGROUND: In patients with ulcerative colitis (UC), laparoscopic pelvic dissection for IPAA is not always straightforward: often, a hand-assistance incision is used to complete the proctectomy, lengthening operative times. Hybrid NOSE and NOTES are emerging as an alternative approach to conventional laparoscopy. We believe that UC patients could benefit from this new hybrid approach in three ways: by easing the proctectomy as performed down to up, avoiding additional incisions and decreasing surgical times. We present the short-term outcomes of our series. METHODS: All patients with UC who required IPAA were enrolled in a single-arm prospective study (July 2011 to March 2014). A three-step procedure was performed. The first step: laparoscopic colectomy (with transanal removal of the colon) and temporary ileostomy. The second step: "down-to-up" proctectomy (with transanal removal of the rectum) and IPAA with a covering ileostomy. We combined simultaneously transanal and laparoscopic approach. The third step: ileostomy closure. Functional outcomes were assessed 3 months after third step. RESULTS: Eighteen patients were enrolled. Two patients are waiting to complete the second stage, and 16 underwent all surgical steps. Twelve have been evaluated with functional scores. For the first step, the mean operative time was 162.2 min (SD 40.5) and 170 min (SD 50.1) for the second one. The median hospital stay was 6 days (IQR 5-14.75) for the first step and 5.5 (IQR 5-9.75) for the second one. No major complications occurred. Twenty-four-hour defecation frequency was 5.5 per day (SD 1.7), 0.5 per night. Seventy-five percentage of patients may retain stools for more than 30 min; the mean value of Oresland score was 4.7 and Wexner score 1.4. CONCLUSIONS: This is a safe and feasible technique to treat UC patients with good short-term outcomes. Long-term outcomes and controlled trials are needed.

Transanal total mesorectal excision in rectal cancer: short-term outcomes in comparison with laparoscopic surgery.

OBJECTIVE: The aim of this study was to compare short-term results obtained with transanal total mesorectal excision (TME) and laparoscopic surgery. BACKGROUND: Transanal TME appears as an alternative in the treatment of rectal cancer and other rectal disease. Natural orifices transluminal endoscopic surgery using the rectum as access in colorectal surgery is intuitively better suited than other access routes. METHODS: All consecutive patients with middle or low rectal cancer submitted to surgery were included into a prospective cohort and treated by transanal TME assisted by laparoscopy. They were compared with a retrospective cohort of consecutive patients of identical characteristics treated by laparoscopic TME in the immediate chronological period. RESULTS: Thirty-seven patients were included in both study groups. No differences were observed between them with respect to baseline characteristics, thus emphasizing the comparability of both cohorts. Surgical time was higher in the laparoscopy group (252 ± 50 minutes) than in the transanal group (215 ± 60 minutes) (P < 0.01). Moreover, coloanal anastomosis was performed less frequently (16% vs 43%, respectively; P = 0.01) and distal margin was lower (1.8 ± 1.2 mm vs 2.7 ± 1.7 mm, respectively; P = 0.05) in the laparoscopy group than in the transanal one. Although there was no significant difference in 30-day postoperative complication rate (laparoscopy, 51% vs transanal, 32%; P = 0.16), early readmissions were more frequent in the laparoscopy group than in the transanal one (22% vs 6%, respectively; P = 0.03). CONCLUSIONS: Evaluation of short-term outcomes demonstrated that transanal TME is a feasible and safe technique associated with a shorter surgical time and a lower early readmission rate.

Cardiorespiratory impact of transesophageal endoscopic mediastinoscopy compared with cervical mediastinoscopy: a randomized experimental study.

BACKGROUND: Transesophageal natural-orifice transluminal endoscopic surgery (NOTES) mediastinoscopy has been described as a feasible, less-invasive alternative to video-assisted mediastinoscopy (VAM). We aimed to investigate hemodynamic and respiratory effects during transesophageal NOTES mediastinoscopy compared with VAM. PATIENTS AND METHODS: This was a short-survival experiment in 20 female pigs randomized to NOTES (n = 10) or VAM (n = 10) mediastinoscopy. In the NOTES group, an endoscopist accessed the mediastinum through a 5-cm submucosal tunnel in the esophageal wall, and CO2 was used to create the pneumomediastinum. Conventional VAM was carried out by thoracic surgeons. A 30-minute systematic exploration of the mediastinum was then performed, including invasive monitoring for hemodynamic and respiratory data. Blood samples were drawn for gas analyses. RESULTS: All experiments except 2 in the NOTES group (one because of technical difficulties, the other because of thoracic lymphatic duct lesion) were completed as planned, and animals survived 24 hours. Also, 3 animals in the NOTES group presented a tension pneumothorax that was immediately recognized and percutaneously drained. VAM and NOTES animals showed similar pulmonary and systemic hemodynamic behavior during mediastinoscopy. Pulmonary gas exchange pattern was mildly impaired during the NOTES procedure, showing lower partial arterial oxygen pressure associated with higher airway pressures (more important in animals that presented with pneumothorax). CONCLUSIONS: NOTES mediastinoscopy induces minimal deleterious respiratory effects and hemodynamic changes similar to conventional cervical VAM and could be feasible when performed under strict hemodynamic and respiratory surveillance. Notably, serious complications caused by the injury of pleura are more frequent in NOTES, which mandates an improvement in technique and suitable equipment.

Stroke volume response to liver graft reperfusion stress in cirrhotic patients.

INTRODUCTION: In patients with advanced cirrhosis, stressful stimuli may reveal a silent reduced cardiac performance. During liver transplantation (LT), graft reperfusion strongly stresses the heart and may unmask latent myocardial dysfunction. AIM: The objective of this study was to assess heart response to acutely increased preload after liver graft reperfusion and correlate this response with preoperative data and outcome. METHODS: Preoperative clinical, echocardiographic, and hemodynamic data, and patient outcome were retrospectively recorded for 235 liver recipients who had no known cardiac disease. Myocardial dysfunction was defined as less than 10 % increase of stroke volume after graft reperfusion (non-responder). RESULTS: We found 84 (35.7 %) non-responder patients. The non-responders showed higher Model for end-stage liver disease scores (p = 0.046), left atrial diameter (LAD) (p = 0.040), hepatic vein pressure gradient (p = 0.055), and hyperdynamic state than responders. The percentages of patients with hyponatremia (p = 0.048) and alcohol etiology (p = 0.025) were also higher among non-responders. Independent predictors of inadequate cardiac response in the multivariate analysis were low preoperative systemic vascular resistance (SVRI) [odds ratio (OR) 3.09, 95 % CI 1.15-4.82; p = 0.027] and enlargement of LAD (OR 2.08, 95 % CI 1.49-2.74; p = 0.044). Non-response was associated with higher rates of early cardiovascular events [hazard ratio (HR) 2.84, 95 % CI 1.09-4.22; p = 0.039] and higher length of intensive care unit stay (p = 0.038). No differences were found in 1-year survival rates. CONCLUSIONS: Latent cardiac dysfunction among LT recipients, considered to be abnormal stroke volume response to unclamping of portal vein, is very prevalent. SVRI and LAD were independent predictors of inadequate responses. This condition deserves special attention since it may aggravate the early postoperative course of LT.

Impact of deep sedation on the accuracy of hepatic and portal venous pressure measurements in patients with cirrhosis.

BACKGROUND & AIMS: Measurement of the hepatic venous pressure gradient (HVPG) offers valuable prognostic information in patients with cirrhosis. In specific circumstances, (children, agitated patients, TIPS placement) deep sedation is required. This study aims to assess the impact of deep sedation on the accuracy of hepatic/portal pressure measurements. METHODS: Forty-four patients were included. Measurements of baseline HVPG (n = 30), HVPG response to i.v. propranolol (n = 11), portal pressure gradient (PPG) after TIPS (n = 27) and of cardio-pulmonary pressures (n = 25) were obtained in awake conditions and under deep sedation with propofol and remifentanil. RESULTS: During deep sedation, a marked oscillation within respiratory cycle was observed in abdominal pressures. End-expiratory sedated HVPG showed a better agreement with awake HVPG (intra-class correlation coefficient - ICC 0.864) than end-inspiratory HVPG (ICC 0.796). However, in almost half of the patients both values differed by more than 10%. Accuracy was not improved by using mean HVPG along the respiratory cycle. Similarly, changes in HVPG caused by propranolol while under sedation had a poor agreement to those obtained in awake conditions. Indeed, about a half of patients were misclassified according to the 10% HVPG reduction target. After TIPS, PPG values obtained under sedation were significantly different to awake PPG, usually underestimating the awake value. The systemic hemodynamic changes induced by sedation were not associated to a greater variability of PPG/HVPG measurements. CONCLUSION: Deep sedation with propofol and remifentanil adds substantial variability and uncertainty to HVPG/PPG measurements. This must be considered when using these values to estimate prognosis, or targeting HVPG/PPG reductions.

Clinical markers of the hypercoagulable state by rotational thrombelastometry in obese patients submitted to bariatric surgery.

BACKGROUND: Metabolic and inflammatory disturbances associated with obesity are considered important trigger factors for venous thromboembolism (VTE). Identification of clinical markers indicating a hypercoagulability state could define a group of high-risk patients in the surgical setting. This study aimed to identify these markers using rotational thrombelastometry (ROTEM) analysis, an established method for hemostasis testing that can detect hyperfunctional stages of the clotting process. METHODS: From June to December 2010, this study investigated 109 consecutive obese patients (28 women and 22 men, mean age 46 years, body mass index 46.6 ± 7 kg/m(2)) with no history of VTE who were candidates for bariatric surgery. Preoperative clinical and metabolic characteristics and ROTEM analysis were recorded. Hypercoagulable risk was defined when patients showed a clot strength (G) of ≥11 dynes/cm(2). RESULTS: Of the 109 patients, 20 (18%) were hypercoagulable according to ROTEM analysis. Metabolic/inflammatory biomarkers such as leptin, C-reactive protein, fibrinogen levels, and platelet count were significantly higher in the high-risk patients. In the multivariate analysis, fibrinogen was an independent predictor of G ≥ 11 dynes/cm(2) [odds ratio (OR) 2.92, 95 % confidence interval (CI) 1.80-5.21, p = 0.023]. After adjustment to other data, only waist circumference affected the prediction [OR 4.42, 95 % CI 2.27-6.71, p = 0.009]. Receiver operating characteristic curve analysis showed that 3.95 g/l was the best cutoff point for fibrinogen predictability (sensitivity 100 %, specificity 41%). CONCLUSION: A hypercoagulability state in obese patients is associated with central obesity and high fibrinogen levels, which should be considered clinical hallmarks of this state. More aggressive perioperative prophylaxis for VTE should be recommended when these hallmarks are present in obese patients.

On-demand endoscopic CO2 insufflation with feedback pressure regulation during natural orifice transluminal endoscopic surgery (NOTES) peritoneoscopy induces minimal hemodynamic and respiratory changes.

BACKGROUND: Endoscopic insufflation has been associated with marked increase in intra-abdominal pressure (IAP) and hemodynamic and respiratory changes during transgastric surgery. OBJECTIVE: To investigate the hemodynamic and respiratory effects during intraperitoneal cavity exploration through 3 different natural orifice transluminal endoscopic surgery (NOTES) access locations compared with laparoscopy. DESIGN AND SETTING: Survival experiments using 40 female pigs randomized to transgastric, transcolonic, transvaginal, and laparoscopic peritoneoscopy. INTERVENTIONS: On-demand endoscopic insufflation of CO(2) with feedback pressure regulation was used in NOTES with a maximum pressure of 14 mm Hg. In the laparoscopy group, the IAP was maintained at 14 mm Hg. NOTES procedures were performed by an endoscopist (with the assistance of a gynecologist in the transvaginal group and a second endoscopist in the transgastric and transrectal groups) and laparoscopy by 2 surgeons. MAIN OUTCOME MEASUREMENTS: Invasive hemodynamic and respiratory data. Blood samples were drawn for gas analyses. RESULTS: All experiments except one in the transrectal group were completed. The IAP was significantly lower in all NOTES groups compared with the laparoscopy group. A significant increase in mean systemic arterial blood pressure was observed in the laparoscopy group at 15 and 30 minutes of intraperitoneal cavity exploration, but it remained unchanged during all NOTES procedures. An increase in airway pressures was observed at 15 and 30 minutes of peritoneoscopy in the animals undergoing laparoscopy, whereas those parameters remained unchanged in the NOTES groups. The laparoscopy group showed a significant impairment in pulmonary gas exchange (decrease in Pao(2), increase in Paco(2), and decrease in arterial pH) after 30 minutes of peritoneoscopy, whereas only a slight increase in Paco(2) was observed in the transrectal and transvaginal groups. LIMITATIONS: Healthy animal model. CONCLUSION: On-demand endoscopic insufflation of CO(2) with feedback pressure regulation can minimize the risk of hemodynamic and respiratory compromise caused by acute changes in IAP.