Feasibility and effects of prehabilitation in cardiac surgery. Preliminary study.

Prehabilitation programs that combine exercise training, nutritional support, and emotional reinforcement have demonstrated efficacy as a strategy for preoperative optimization in abdominal surgery. The experience in cardiac surgery, one of those associated with greater morbidity and mortality, is anecdotal. OBJECTIVE: evaluation of the feasibility of a multimodal prehabilitation program and its effect on functional capacity in patients candidates for elective cardiac surgery. METHODS: Pilot study conducted from July 2017 to June 2018 in patients candidates to myocardial revascularization and/or valve replacement. The program consisted of: 1) supervised exercise training program, 2) breathing incentive exercises, 3) nutritional support, and 4) mindfulness training. An evaluation was carried out prior to the start of the program and at the end of it (preoperatively). RESULTS: All patients except one who refused surgery, completed the program, which lasted an average of 45 days. No patients presented complications related to the program. The program induced a significantly increase in functional capacity measured by the six-minute walking test (510.7 + 62 m vs 534.3 + 71 m, p = 0.007) and the chair test (13.2 + 4, 7 vs 16.4 + 7 repetitions, p = 0.02), as well as an increase in the level of physical activity measured by the Yale physical activity questionnaire (37.6 + 20 vs 54.2 + 27; p = 00029). CONCLUSIONS: Multimodal prehabilitation in patients candidates for elective cardiac surgery is feasible and it increases functional capacity preoperatively without being associated with complications. The presumed beneficial impact of this improvement on the incidence of postoperative complications and hospital stay, requires further investigation.

Factors Associated with Prolonged Recipient Hepatectomy Time During Liver Transplantation: A Single-Centre Experience.

BACKGROUND: Recipient hepatectomy during liver transplantation can be a challenging operation and can increase cold ischaemic time. The aim of this study is to assess factors associated with prolonged recipient hepatectomy. METHODS: From 2005 to 2015, 930 patients were submitted to liver transplantation in our hospital. Prolonged hepatectomy time was defined as operative time >180 min (from knife on skin to total hepatectomy). Patients undergoing early liver retransplantation and living donation were excluded. RESULTS: A total of 715 patients were included in our study. Median age at transplantation was 53 (18-70) years, and median BMI was 26.2 (16-40). Median hepatectomy time was 131 min. Prolonged hepatectomy time occurred in 89 (12.4%) patients. At univariate analysis, previous decompensated cirrhosis with variceal bleeding and/or ascites, higher BMI and previous abdominal surgery were associated with prolonged operating time. Higher surgeon experience and acute liver failure were associated with shorter hepatectomy time. At multivariate analysis, previous episodes of variceal bleeding (p = 0.027, OR 1.78), BMI > 27 (p = 0.01, OR 1.75), previous abdominal surgery (p = 0.04, OR 1.68) and surgeon experience (p = 0.007, OR 2.04) were independently associated with operating time. Prolonged hepatectomy time was significantly associated with cold and total ischaemic time and intraoperative bleeding (p < 0.001, p = 0.002 and p = 0.002, respectively). CONCLUSIONS: Recipient BMI, previous episodes of variceal bleeding, previous abdominal surgery and surgeon experience are independently associated with hepatectomy duration. These factors can be helpful to identify those patients with potentially prolonged hepatectomy time, and therefore, strategies can be put in place to optimize outcomes in this group of patients.

Post-discharge impact and cost-consequence analysis of prehabilitation in high-risk patients undergoing major abdominal surgery: secondary results from a randomised controlled trial.

BACKGROUND: Prehabilitation may reduce postoperative complications, but sustainability of its health benefits and impact on costs needs further evaluation. Our aim was to assess the midterm clinical impact and costs from a hospital perspective of an endurance-exercise-training-based prehabilitation programme in high-risk patients undergoing major digestive surgery. METHODS: A cost-consequence analysis was performed using secondary data from a randomised, blinded clinical trial. The main outcomes assessed were (i) 30-day hospital readmissions, (ii) endurance time (ET) during an exercise testing, and (iii) physical activity by the Yale Physical Activity Survey (YPAS). Healthcare use for the cost analysis included costs of the prehabilitation programme, hospitalisation, and 30-day emergency room visits and hospital readmissions. RESULTS: We included 125 patients in an intention-to-treat analysis. Prehabilitation showed a protective effect for 30-day hospital readmissions (relative risk: 6.4; 95% confidence interval [CI]: 1.4-30.0). Prehabilitation-induced enhancement of ET and YPAS remained statistically significant between groups at the end of the 3 and 6 month follow-up periods, respectively (ΔET 205 [151] s; P=0.048) (ΔYPAS 7 [2]; P=0.016). The mean cost of the programme was €389 per patient and did not increment the total costs of the surgical process (€812; CI: 95% -878 - 2642; P=0.365). CONCLUSIONS: Prehabilitation may result in health value generation. Moreover, it appears to be a protective intervention for 30-day hospital readmissions, and its effects on aerobic capacity and physical activity may show sustainability at midterm. CLINICAL TRIAL REGISTRATION: NCT02024776.

Physical activity and frailty as indicators of cardiorespiratory reserve and predictors of surgical prognosis: General and digestive surgery population characterization. / Actividad física y fragilidad como indicadores de reserva cardiorrespiratoria y predictores del pronóstico quirúrgico: caracterización de la población quirúrgica en cirugía general y digestiva.

INTRODUCTION: Frailty and low physical activity and cardiorespiratory reserve are related to higher perioperative morbimortality. The crucial step in improving the prognosis is to implement specific measures to optimize these aspects. It is critical to know the magnitude of the problem in order to implement preoperative optimization programmes. OBJECTIVE: To characterize surgical population in a university hospital. METHODS: All patients undergoing preoperative evaluation for abdominal surgery with admission were prospectively included during a 3-month period. Level of physical activity, functional capacity, frailty and emotional state were assessed using score tests. Additionally, physical condition was evaluated using 5 Times Sit-to-Stand Test. Demographic, clinical and surgical data were collected. RESULTS: One hundred and forty patients were included (60±15yr-old, 56% male, 25% ASA III or IV). Forty-nine percent of patients were proposed for oncologic surgery and 13% of which had received neoadjuvant treatment. Seventy percent of patients presented a low functional capacity and were sedentary. Eighteen percent of patients were considered frail and more than 50% completed the 5 Times Sit-to-Stand Test at a higher time than the reference values adjusted to age and sex. Advanced age, ASA III/IV, sedentarism, frailty and a high level of anxiety and depression were related to a lower functional capacity. CONCLUSIONS: The surgical population of our area has a low functional reserve and a high index of sedentary lifestyle and frailty, predictors of postoperative morbidity. It is mandatory to implement preoperative measures to identify population at risk and prehabilitation programmes, considered highly promising preventive interventions towards improving surgical outcome.

[Fibreoptic clinical training in anaesthesia. Course design and results based on a self-assessment survey]. / Entrenamiento clínico con fibrobroncoscopio en anestesia. Diseño y resultados del curso según encuesta de autoevaluación.

BACKGROUND AND OBJECTIVE: Fibreoptic intubation is the technique of choice for resolving complications related to a difficult airway. Our aim was to determine whether a clinical-practice-based, individualized course provides sufficient training and confidence to allow anaesthetists to routinely practice fibreoptic intubation. METHODS: Our hospital developed a clinical-practice-based, individualized course on fibreoptic intubation in general anaesthesia that provided practice in sedated spontaneously breathing patients and insertion through supraglottic devices. From 2005 to 2009, we e-mailed participants for response to an anonymous online self-assessment survey. We asked participants about the training outcomes and their overall degree of satisfaction. RESULTS: Seventy-seven participants were sent the questionnaire six months after the course and 61% responded. All respondents considered themselves skilled in handling the bronchoscope at the end of the course and 97% used it in their routine practice in patients with difficult airways. CONCLUSIONS: These results suggest a high success rate can be expected from individually tailored fibreoptic intubation courses that supplement theory and mannequin experience with clinical practice.

[An established anesthesia team-care model: over 12000 cases in a digestive endoscopy unit]. / Consolidación de un modelo asistencial basado en un equipo de anestesia: experiencia en más de 12.000 casos en una Unidad de Endoscopia Digestiva.

BACKGROUND AND OBJECTIVE: The growing demand for digestive and other endoscopic procedures outside the operating room, both in terms of type of endoscopy and number of patients, requires reorganization of the anesthesiology department's workload. We describe 2 years of our hospital digestive endoscopy unit's experience with a now well-established care model involving both anesthesiologists and nurse anesthetists. MATERIAL AND METHODS: After previously reviewing the medical records of outpatients and conducting a telephone interview about state of health, nurse anesthetists administered a combination of propofol and remifentanil through a target-controlled infusion system under an anesthesiologist's direct supervision. RESULTS: The ratio of anesthesiologists to nurses ranged from 1:2 to 1:3 according to the complexity of the examination procedure. Over 12000 endoscopies (simple to advanced) in a total of 11853 patients were performed under anesthesia during the study period. Airway management maneuvers were required by 4.9% of the patients; 0.18% required bag ventilation for respiratory depression, and 0.084% required bolus doses of a vasopressor to treat hypotension or atropine to treat bradycardia. The procedure had to be halted early in 9 patients (0.07%). No patient required orotracheal intubation and none died. Nor were any complications related to sedation recorded. CONCLUSION: The results suggest that this care model can safely accommodate a large caseload in anesthesia at an optimum level of quality.

Modeling the effect of propofol and remifentanil combinations for sedation-analgesia in endoscopic procedures using an Adaptive Neuro Fuzzy Inference System (ANFIS).

BACKGROUND: The increasing demand for anesthetic procedures in the gastrointestinal endoscopy area has not been followed by a similar increase in the methods to provide and control sedation and analgesia for these patients. In this study, we evaluated different combinations of propofol and remifentanil, administered through a target-controlled infusion system, to estimate the optimal concentrations as well as the best way to control the sedative effects induced by the combinations of drugs in patients undergoing ultrasonographic endoscopy. METHODS: One hundred twenty patients undergoing ultrasonographic endoscopy were randomized to receive, by means of a target-controlled infusion system, a fixed effect-site concentration of either propofol or remifentanil of 8 different possible concentrations, allowing adjustment of the concentrations of the other drug. Predicted effect-site propofol (C(e)pro) and remifentanil (C(e)remi) concentrations, parameters derived from auditory evoked potential, autoregressive auditory evoked potential index (AAI/2) and electroencephalogram (bispectral index [BIS] and index of consciousness [IoC]) signals, as well as categorical scores of sedation (Ramsay Sedation Scale [RSS] score) in the presence or absence of nociceptive stimulation, were collected, recorded, and analyzed using an Adaptive Neuro Fuzzy Inference System. The models described for the relationship between C(e)pro and C(e)remi versus AAI/2, BIS, and IoC were diagnosed for inaccuracy using median absolute performance error (MDAPE) and median root mean squared error (MDRMSE), and for bias using median performance error (MDPE). The models were validated in a prospective group of 68 new patients receiving different combinations of propofol and remifentanil. The predictive ability (P(k)) of AAI/2, BIS, and IoC with respect to the sedation level, RSS score, was also explored. RESULTS: Data from 110 patients were analyzed in the training group. The resulting estimated models had an MDAPE of 32.87, 12.89, and 8.77; an MDRMSE of 17.01, 12.81, and 9.40; and an MDPE of -1.86, 3.97, and 2.21 for AAI/2, BIS, and IoC, respectively, in the absence of stimulation and similar values under stimulation. P(k) values were 0.82, 0.81, and 0.85 for AAI/2, BIS, and IoC, respectively. The model predicted the prospective validation data with an MDAPE of 34.81, 14.78, and 10.25; an MDRMSE of 16.81, 15.91, and 11.81; an MDPE of -8.37, 5.65, and -1.43; and P(k) values of 0.81, 0.8, and 0.8 for AAI/2, BIS, and IoC, respectively. CONCLUSION: A model relating C(e)pro and C(e)remi to AAI/2, BIS, and IoC has been developed and prospectively validated. Based on these models, the (C(e)pro, C(e)remi) concentration pairs that provide an RSS score of 4 range from (1.8 µg·mL(-1), 1.5 ng·mL(-1)) to (2.7 µg·mL(-1), 0 ng·mL(-1)). These concentrations are associated with AAI/2 values of 25 to 30, BIS of 71 to 75, and IoC of 72 to 76. The presence of noxious stimulation increases the requirements of C(e)pro and C(e)remi to achieve the same degree of sedative effects.

The role of a computed tomography-based image registered navigation system for natural orifice transluminal endoscopic surgery: a comparative study in a porcine model.

BACKGROUND AND STUDY AIMS: Most natural orifice transluminal endoscopic surgery (NOTES) procedures have been performed in animal models through the anterior stomach wall, but this approach does not provide efficient access to all anatomic areas of interest. Moreover, injury of the adjacent structures has been reported when using a blind access. The aim of the current study was to assess the utility of a CT-based (CT: computed tomography) image registered navigation system in identifying safe gastrointestinal access sites for NOTES and identifying intraperitoneal structures. METHODS: A total of 30 access procedures were performed in 30 pigs: anterior gastric wall (n = 10), posterior gastric wall (n = 10), and anterior rectal wall (n = 10). Of these, 15 procedures used image registered guidance (IR-NOTES) and 15 procedures used a blind access (NOTES only). Timed abdominal exploration was performed with identification of 11 organs. The location of the endoscopic tip was tracked using an electromagnetic tracking system and was recorded for each case. Necropsy was performed immediately after the procedure. The primary outcome was the rate of complications; secondary outcome variables were number of organs identified and kinematic measurements. RESULTS: A total of 30 animals weighting a mean (± SD) of 30.2 ± 6.8 kg were included in the study. The incision point was correctly placed in 11 out of 15 animals in each group (73.3 %). The mean peritoneoscopy time and the number of properly identified organs were equivalent in the two groups. There were eight minor complications (26.7 %), two (13.3 %) in the IR-NOTES group and six (40.0 %) in the NOTES only group ( P = n. s.). Characteristics of the endoscope tip path showed a statistically significant improvement in trajectory smoothness of motion for all organs in the IR-NOTES group. CONCLUSION: The image registered system appears to be feasible in NOTES procedures and results from this study suggest that image registered guidance might be useful for supporting navigation with an increased smoothness of motion.

Endoscopic ultrasound-guided fine-needle aspiration and trucut biopsy in the diagnosis of gastric stromal tumors: a randomized crossover study.

BACKGROUND AND AIM: The diagnosis of gastrointestinal stromal tumors (GISTs) has important prognostic and therapeutic implications. The specific diagnosis of GIST has to be based on immunocytochemistry. This study aimed to prospectively compare in a crossover manner the accuracy of endoscopic ultrasound (EUS)-guided fine-needle aspiration (EUS-FNA) and EUS-guided trucut biopsy (EUS-TCB) in the specific diagnosis of gastric GISTs. We hypothesized that EUS-TCB is superior to EUS-FNA in this respect. PATIENTS AND METHODS: Forty patients with gastric subepithelial tumors suspected on the basis of EUS of being a GIST underwent both EUS-FNA and EUS-TCB. The sequence in which the techniques were employed was randomly assigned to avoid bias. RESULTS: Forty tumors were sampled (mean number of passes: 2.1 +/- 0.9 with EUS-TNB and 1.9 +/- 0.8 with EUS-FNA; P = not significant, NS). Final diagnoses were: GIST (n = 27), carcinoma (n = 2), leiomyoma (n = 1), schwannoma (n = 1), and no diagnosis possible (n = 9). Device failure occurred in 6 patients with EUS-TCB. A cytohistological diagnosis of mesenchymal tumor (n = 29) and carcinoma (n = 2) was made in 70 % of cases by EUS-FNA and in 60 % of cases by EUS-TCB ( P = NS). Among the samples that were adequate, immunohistochemistry could be performed in 74 % of EUS-FNA samples and in 91 % of EUS-TCB samples ( P = 0.025). When inadequate samples were included, the overall diagnostic accuracy of EUS-FNA was 52 % and that of EUS-TCB was 55 % ( P = NS). There were no complications. CONCLUSIONS: EUS-TCB is not superior to EUS-FNA in GISTs because of the high rate of technical failure of trucut. However, when an adequate sample is obtained with EUS-TCB, immunohistochemical phenotyping is almost always possible. EUS-TCB can be safely performed in this set of patients.

Severe complications limit long-term clinical success of self-expanding metal stents in patients with obstructive colorectal cancer.

OBJECTIVES: Self-expanding metal stents (SEMS) are increasingly being used to treat malignant colorectal obstruction. However, complications have been reported in up to 50% of patients. There is limited information on long-term outcomes of these patients. The aim of this study was to retrospectively assess the long-term clinical success of SEMS in patients with malignant colorectal obstruction in a single tertiary center and to identify possible predictive factors of developing complications. METHODS: A total of 47 attempts to insert colorectal SEMS were made in 47 patients during a 5-year period. Stents of 9-cm length were placed under endoscopic and radiologic monitoring. After 24 h, all patients underwent abdominal X-ray to verify correct positioning of the stent. Patients were followed at the outpatient clinic. RESULTS: Insertion success was achieved in 44 (94%) patients. Acceptable initial colonic decompression was observed in 44 out of 47 (94%) attempts and in all (100%) successfully inserted stents. The stents were placed in the rectum (n=7, 15%), sigmoid (n=33, 70%), left colon (n=4, 9%), or anastomosis (n=3, 6%). The majority of patients had stage IV disease (n=40, 85%). SEMS served as a bridge to scheduled surgery in 9 (20%) patients and as a palliative definitive treatment in 38 (80%) cases. Three patients were lost to follow-up, so the outcome was evaluated in 41 patients. Long-term clinical failure occurred in 21 (51%) patients and was due to complications such as: migration (n=9, 22%), obstruction (n=7, 17%), perforation (n=3, 7%), and tenesmus (n=2, 5%). Perforations occurred 3, 4, and 34 days after insertion, and all patients died. In the bridge-to-surgery group, primary anastomosis was possible in only four of nine patients (44%). Clinical failure was not associated with any tumor-related factor. However, eight of nine patients with stent migration and two of three patients with perforation had been previously treated with chemotherapy. CONCLUSIONS: Placement of SEMS does not seem to be as effective as suggested because of late complications. For patients with potentially curable lesions, the use of colonic stents for malignant obstruction should only be considered when surgery is scheduled shortly after the stent insertion. Moreover, in patients with incurable obstructing colorectal cancer eligible for chemotherapy and a long life expectancy, palliative treatments other than SEMS should be considered.

The effects of vasoactive drugs on hepatic blood flow changes induced by CO2 laparoscopy: an animal study.

UNLABELLED: Laparoscopic surgery is associated with systemic and splanchnic hemodynamic alterations. Recent data suggest that small-dose dobutamine may attenuate the reduction in splanchnic blood flow associated with increments in intraabdominal pressure. We conducted this study to analyze the effects of dopamine and dobutamine on the hepatic circulation in this setting. Twenty-one pigs were anesthetized and mechanically ventilated. A flow-directed pulmonary artery and carotid artery catheters were inserted. Perivascular flow probes were placed around the main hepatic artery and the portal vein. CO2 was insufflated into the peritoneal cavity to reach an intraabdominal pressure of 15 mm Hg. After 60 min, animals received dopamine (5 microg x kg(-1) x min(-1); n = 8), dobutamine (5 microg x kg(-1) x min(-1); n = 8), or saline (n = 5) for 30 min. Pneumoperitoneum induced significant increases in heart rate, mean arterial pressure, and systemic vascular resistance, with decreases in cardiac output and hepatic artery and portal vein blood flows. Dobutamine infusion, in contrast to dopamine, corrected, at least in part, cardiac output, systemic vascular resistance, and hepatic artery blood flow alterations, but neither drug restored total hepatic blood flow. IMPLICATIONS: Hepatic blood flow decreases during laparoscopic surgery. A small-dose infusion of neither dobutamine nor dopamine corrects the total hepatic blood flow impairment, but the former is able to restore the hepatic arterial blood supply in an animal model mimicking this condition.

Effects of carbon dioxide vs helium pneumoperitoneum on hepatic blood flow.

BACKGROUND: Elevated intraabdominal pressure due to gas insufflation for laparoscopic surgery may result in regional blood flow changes. Impairments of hepatic, splanchnic, and renal blood flow during peritoneal insufflation have been reported. Therefore we set out to investigate the effects of peritoneal insufflation with helium (He) and carbon dioxide (CO2) on hepatic blood flow in a porcine model. METHODS: Twelve pigs were anesthetized and mechanically ventilated with a fixed tidal volume after the stabilization period. Peritoneal cavity was insufflated with CO2 (n = 6) or He (n = 6) to a maximum intraabdominal pressure of 15 mmHg. Hemodynamic parameters, gas exchange, and oxygen content were studied at baseline, 90 mm and 150 min after pneumoperitoneum, and 30 min after desufflation. Determination of hepatic blood flow with indocyanine green was made at all measured points by a one-compartment method using hepatic vein catheterization. RESULTS: A similar decrease in cardiac output was observed during insufflation with both gases. Hepatic vein oxygen content decreased with respect to the baseline during He pneumoperitoneum (p < 0.05), but it did not change during CO2 insufflation. Hepatic blood flow was significantly reduced in both the He and CO2 pneumoperitoneums at 90 min following insufflation (63% and 24% decrease with respect to the baseline; p < 0.001 and p < 0.05, respectively) being this decrease marker in the He group (p = 0.02). CONCLUSIONS: These findings suggest that helium intraperitoneal insufflation results in a greater impairment on hepatic blood flow than CO2 insufflation.

[Measurement of exhaled nitric oxide in healthy subjects]. / Medición del óxido nítrico exhalado en sujetos sanos.

BACKGROUND: Endogenously synthesized nitric oxide (NO) is present in exhaled air and its analysis could be used as a tool to monitor inflammatory airway diseases. The objective of the present study was to develop the methodology for the measurement of exhaled NO and to obtain reference values in a group of healthy subjects. SUBJECTS AND METHOD: Exhaled NO was measured in 40 healthy subjects and 22 asthmatic patients using a single breath manoeuvre and a chemiluminescence analyzer. Comparisons of exhaled NO while breathing both, room air and medical air, were performed in 20 subjects. In seven asthmatic patients we evaluated the effect of an inhibitor of NO-synthesis (L-NAME). RESULTS: Mean (SD) exhaled NO in healthy subjects was 18 (13) parts per billion (ppb). Intraindividual variability was 6.5 (6.5%). The concentration of exhaled NO could be overestimated when environmental NO was high (> 80 ppb). Smokers showed lower levels than nonsmokers (10 [7] vs 22 [13] ppb, respectively; p < 0.005), whereas asthmatic patients showed higher exhaled NO levels (62 [31] ppb; p < 0.001). In these patients nebulization of L-NAME induced a progressive fall in exhaled NO (maximal decrease, -68 [15%]; p < 0.01). CONCLUSIONS: The measurement of NO concentration in exhaled air is reproducible, not influenced by the usual levels of environmental NO, and sensible enough to detect changes induced by the administration of a specific inhibitor. Exhaled NO concentration decreases in smokers and increases in asthmatics.

Epidural hematoma after epidural anesthesia in a patient with peripheral vascular disease. Case report.

BACKGROUND AND OBJECTIVES: Epidural hematoma is a severe, uncommon complication associated with epidural anesthesia in patients with peripheral vascular disease who require anticoagulant therapy. METHODS: An 84-year-old woman with acute left leg arterial ischemia underwent revascularization surgery under lumbar epidural anesthesia. Pre- and postoperative heparin was administered as an anticoagulant. RESULTS: Reperfusion of the leg was successful, however, 3 days later clinical signs of spinal cord compression appeared and epidural hematoma was diagnosed. Neurologic recovery was poor. CONCLUSIONS: This case highlights the need for careful individual preoperative analysis and postoperative observation to make anesthetic practice safe in patients receiving perioperative anticoagulant therapy.