High intraoperative inspiratory oxygen fraction and risk of major respiratory complications.

BACKGROUND: High inspiratory oxygen fraction ( FIO2 ) may improve tissue oxygenation but also impair pulmonary function. We aimed to assess whether the use of high intraoperative FIO2 increases the risk of major respiratory complications. METHODS: We studied patients undergoing non-cardiothoracic surgery involving mechanical ventilation in this hospital-based registry study. The cases were divided into five groups based on the median FIO2 between intubation and extubation. The primary outcome was a composite of major respiratory complications (re-intubation, respiratory failure, pulmonary oedema, and pneumonia) developed within 7 days after surgery. Secondary outcomes included 30-day mortality. Several predefined covariates were included in a multivariate logistic regression model. RESULTS: The primary analysis included 73 922 cases, of whom 3035 (4.1%) developed a major respiratory complication within 7 days of surgery. For patients in the high- and low-oxygen groups, the median FIO2 was 0.79 [range 0.64-1.00] and 0.31 [0.16-0.34], respectively. Multivariate logistic regression analysis revealed that the median FIO2 was associated in a dose-dependent manner with increased risk of respiratory complications (adjusted odds ratio for high vs low FIO2 1.99, 95% confidence interval [1.72-2.31], P -value for trend <0.001). This finding was robust in a series of sensitivity analyses including adjustment for intraoperative oxygenation. High median FIO2 was also associated with 30-day mortality (odds ratio for high vs low FIO2 1.97, 95% confidence interval [1.30-2.99], P -value for trend <0.001). CONCLUSIONS: In this analysis of administrative data on file, high intraoperative FIO2 was associated in a dose-dependent manner with major respiratory complications and with 30-day mortality. The effect remained stable in a sensitivity analysis controlled for oxygenation. CLINICAL TRIAL REGISTRATION: NCT02399878.

Confirmation of the role of diabetes in the local recurrence of surgically resected non-small cell lung cancer.

PURPOSE: We recently demonstrated that diabetes mellitus was an independent risk factor for local recurrence (LR) for patients undergoing resection of non-small cell lung cancer (NSCLC). This investigation was performed to confirm or refute this finding in a different patient cohort. MATERIALS AND METHODS: Patients were eligible if they did not have a second primary cancer within 5 years of the original diagnosis, had at least 3-month follow-up, and did not receive radiotherapy. There were 373 and 168 patients in the original (P1) and confirmatory (P2) cohorts, respectively, with 66 and 30 patients with diabetes. RESULTS: The median follow-up was 33 months (range, 3-98 months). Diabetes was an independent risk factor for LR in a Cox model in both the P2 (p=0.05, hazard ratio [HR] 2.15) and P1 (p=0.008, HR 1.90) cohorts, separately from BMI, glucose control, and the presence of the metabolic syndrome. The rates of LR in the patients with diabetes after combining the cohorts at 2, 3, and 5 years were 23%, 33%, and 56%, respectively; these rates were 15%, 19%, and 26% in non-diabetics. In multivariate Cox regression and competing risk analysis of the combined cohorts, the HRs for LR in patients with diabetes exceeded those of more established risk factors for LR including a 1-cm increase in tumor size and lymphovascular invasion. CONCLUSIONS: Diabetes was confirmed to be an independent predictor of the risk of LR following resection of NSCLC.

[Effect of doxorubicine and heterogenous electromagnetic and thermal fields on the nonlinear dynamics of carcinoma Guerin development].

While local hyperthermia application the intratumoral blood flow is enhancing, leading to oxygenation and vascular permeability for antitumoral medicines. The work objective was to investigate the dependence of the development kinetics in carcinoma Gereni (CG) from combined action of doxorubicin (DR) and the kind of thermal impact, a contact one--due to a contact delivery of heat from a water heater and without contact - due to the tumor electromagnetic irradiation (EMI) using heterogenous electromagnetic field (EMF). DR was injected to the animals in a mass concentration of 1,5 mg on 1 kg of their body mass. The DR injection, a contact heating and EMI were started on the 8th day after the tumor reinoculation and kept on conducting once a 2 days. The course had included 5 injections and/or 5 seances of a contact heating and/or EMF. The combined action of DR and EMI, using spatially heterogenous EMF of applicator in environment of physiological hyperthermia, have had influenced mostly the inhibition of a nonlinear dynamics in CG development. Antitumoral action of DR in the animals with CG was influenced by thermal and nonthermal effects, which were initiated by spatially heterogenous EMF. Nonlinear dynamics of a CG development in animals did not depend from horizontal direction of isolines of a spatially heterogenous EMF of inductive applicator towards the tumor and duration of the irradiation procedure (15 or 30 minutes) after DR injection. The data obtained were exploited in clinical practice for the inductothermy optimal regimes elaboration while conducting complex treatment of patients, suffering oncological diseases.

Methylprednisolone does not benefit patients undergoing coronary artery bypass grafting and early tracheal extubation.

OBJECTIVE: We sought to determine whether methylprednisolone, when administered to patients undergoing cardiac surgery, is able to ward off the detrimental hemodynamic and pulmonary alterations associated with cardiopulmonary bypass. METHODS: After institutional review board approval and informed consent was obtained, 90 patients scheduled for elective cardiac surgery were randomized to 1 of 3 groups. Group 30MP patients received 30 mg/kg intravenous methylprednisolone during sternotomy and 30 mg/kg during initiation of cardiopulmonary bypass, group 15MP patients received 15 mg/kg methylprednisolone at the same 2 times, and group NS patients received similar volumes of isotonic sodium chloride solution at the same 2 times. Perioperative care was standardized, and all caregivers were blinded to treatment group. Various hemodynamic and pulmonary measurements were obtained perioperatively, as well as fluid balance, weight, peak postoperative blood glucose level, and tracheal extubation time. RESULTS: Demographic and clinical characteristics of patients and intraoperative data were similar among the 3 groups. Patients receiving methylprednisolone (either dose) exhibited significantly increased cardiac index (P =.0006), significantly decreased systemic vascular resistance (P =.0005), and significantly increased shunt flow (P =.0020) during the immediate postoperative period. All 3 groups exhibited significant increases in alveolar-arterial oxygen gradient (P <.0001), significant decreases in dynamic lung compliance (P <.0001), and significant decreases in static lung compliance (P <.0001) during the immediate postoperative period, with no differences between groups. Perioperative fluid balance and weights were similar between groups. A statistically significant difference in peak postoperative blood glucose level existed (P =.016) among group NS (234 +/- 96 mg/dL), group 15MP (292 +/- 93 mg/dL), and group 30MP (311 +/- 90 mg/dL). In patients extubated within 12 hours of intensive care unit arrival, a statistically significant difference in extubation times existed (P =.025) between group NS (5.7 +/- 2.3 hours), group 15MP (5.9 +/- 2.2 hours), and group 30MP (7.5 +/- 2.7 hours). CONCLUSIONS: Methylprednisolone, as used in this investigation, offers no clinical benefits to patients undergoing elective coronary artery bypass grafting with cardiopulmonary bypass and may in fact be detrimental by initiating postoperative hyperglycemia and possibly hindering early postoperative tracheal extubation for undetermined reasons.

Protective ventilation attenuates postoperative pulmonary dysfunction in patients undergoing cardiopulmonary bypass.

OBJECTIVE: To ascertain if protective ventilation can attenuate the damaging postoperative pulmonary effects of cardiopulmonary bypass (increases in airway pressure, decreases in lung compliance, and increases in shunt). DESIGN: Prospective, randomized clinical trial. SETTING: Single university hospital. PARTICIPANTS: Twenty-five patients undergoing elective coronary artery bypass graft procedure and early extubation. INTERVENTIONS: Thirteen patients received conventional mechanical ventilation (CV; respiratory rate, 8 breaths/min; tidal volume, 12 mL/kg; fraction of inspired oxygen [FIO2], 1.0; positive end-expiratory pressure [PEEP], +5), and 12 patients received protective mechanical ventilation (PV; respiratory rate, 16 breaths/min; tidal volume, 6 mL/kg; FIO2, 1.0; PEEP, +5). Perioperative anesthetic and surgical management were standardized. Various pulmonary parameters were determined twice perioperatively: 10 minutes after intubation and 60 minutes after arrival in the intensive care unit. MEASUREMENTS AND MAIN RESULTS: The mean postoperative increase in peak airway pressure in group CV was significantly larger than the mean postoperative increase in peak airway pressure in group PV (7.1 v 2.4 cm H2O; p < 0.001). Group CV experienced significant postoperative increases in plateau airway pressure (p = 0.007), but group PV did not (p = 0.644). The mean postoperative decrease in dynamic lung compliance in group CV was significantly larger than the mean postoperative decrease in dynamic lung compliance in group PV (14.9 v 5.5 mL/cm H2O; p = 0.002). Group CV experienced significant postoperative decreases in static lung compliance (p = 0.014), but group PV did not (p = 0.645). Group CV experienced significant postoperative increases in shunt (15.5% to 21.4%; p = 0.021), but group PV did not (18.4% to 21.2%; p = 0.265). CONCLUSIONS: Data indicate that protective ventilation decreases pulmonary damage caused by mechanical ventilation in normal and abnormal lungs. The results of this investigation indicate that protective ventilation may also help attenuate the postoperative pulmonary dysfunction (increases in airway pressure, decreases in lung compliance, and increases in shunt) commonly seen in patients after exposure to cardiopulmonary bypass.

Port-access minimally invasive cardiac surgery increases surgical complexity, increases operating room time, and facilitates early postoperative hospital discharge.

BACKGROUND: Proposed advantages of port-access cardiac surgery have yet to be substantiated. The authors retrospectively compared patients undergoing port-access cardiac surgery with a matched group undergoing conventional cardiac surgery. METHODS: Forty-six patients who underwent port-access cardiac surgery were matched with 46 who underwent conventional cardiac surgery. Absolute criteria for matching included morning-of-surgery admission, procedure undergone, and care being delivered by one of two surgeons. If possible, matching included care delivered by one of two anesthesiologists. Patients were matched as closely as possible for preoperative demographic and clinical characteristics. RESULTS: All 46 pairs of patients were matched for procedure and admitted the morning of surgery. All 92 operations were performed by one of two surgeons, and 89% were performed by one of two anesthesiologists. Preoperative demographic and clinical characteristics were equivalent between groups. Compared with conventional cardiac surgery, port-access cardiac surgery increased surgical complexity (it almost tripled cardiopulmonary bypass time during coronary artery bypass grafting and increased it almost 40% during mitral valve procedures) and increased total operating room time (P < 0.0001). Port-access cardiac surgery had no beneficial effect on earlier postoperative extubation, decreased incidence of atrial fibrillation, or intensive care unit time, yet it decreased postoperative duration of stay (P = 0.029, all patients), a benefit observed primarily in patients undergoing coronary artery bypass grafting (P = 0.002). CONCLUSIONS: This retrospective analysis revealed that port-access cardiac surgery increases surgical complexity, increases operating room time, has no effect on earlier postoperative extubation or decreased incidence of atrial fibrillation or intensive care unit time, and may facilitate postoperative hospital discharge (primarily in patients undergoing coronary artery bypass grafting). Properly designed prospective investigation is necessary to ascertain whether port-access cardiac surgery truly offers any benefits over conventional cardiac surgery.

Attempting to maintain normoglycemia during cardiopulmonary bypass with insulin may initiate postoperative hypoglycemia.

UNLABELLED: We attempted to develop an insulin administration protocol that maintains normoglycemia in patients undergoing cardiac surgery and to study the effects of intraoperative blood glucose management on serum levels of creatine phosphokinase isoenzyme BB (CK-BB) and S-100 protein. Twenty nondiabetic patients were randomly allocated to receive either "tight control" of blood glucose with a standardized IV insulin infusion intraoperatively (Group TC) or "no control" of blood glucose intraoperatively (Group NC). Perioperative serum levels of glucose, CK-BB, and S-100 protein were determined in all patients. Group TC patients received 90.0 +/- 49.2 units of insulin, whereas Group NC patients received none. Despite insulin, both Group TC (P = 0.00026) and Group NC (P = 0.00003) experienced similar significant increases in blood glucose levels during hypothermic cardiopulmonary bypass. However, mean blood glucose level upon intensive care unit arrival was significantly decreased in Group TC, compared with Group NC (84.7 +/- 41.0 mg/dL, range 32-137 mg/dL vs 201.4 +/- 67.5 mg/dL, range 82-277 mg/dL, respectively; P = 0.0002). Forty percent of Group TC patients required treatment for postoperative hypoglycemia (blood glucose level <60 mg/dL). Substantial interindividual variability existed in regard to insulin resistance. The investigation was terminated after we realized that normoglycemia was unattainable with the study protocol and that postoperative hypoglycemia was unpredictable. All patients in both groups experienced similar significant increases in postoperative serum levels of CK-BB and S-100 protein. These results indicate that "tight control" of intraoperative blood glucose in nondiabetic patients undergoing cardiac surgery was unattainable with the study protocol and may initiate postoperative hypoglycemia. IMPLICATIONS: The appropriate intraoperative management of hyperglycemia and whether it adversely affects neurologic outcome in patients after cardiac surgery remains controversial. This investigation reveals that attempting to maintain normoglycemia in this setting with insulin may initiate postoperative hypoglycemia.

Intrathecal morphine for coronary artery bypass graft procedure and early extubation revisited.

OBJECTIVE: To determine the dose of intrathecal (IT) morphine (along with the intraoperative baseline anesthetic) that provides significant analgesia yet does not delay extubation in the immediate postoperative period in patients undergoing cardiac surgery and early extubation. DESIGN: Prospective, randomized, double-blinded, placebo-controlled clinical study. SETTING: Single university hospital. PARTICIPANTS: Forty patients undergoing elective coronary artery bypass graft procedure and early extubation. INTERVENTIONS: Twenty patients received 10 microg/kg of IT morphine, and 20 patients received IT placebo. Perioperative anesthetic management was standardized and included postoperative patient-controlled morphine analgesia. MAIN RESULTS: Of the patients tracheally extubated during the immediate postoperative period, mean time to extubation was similar in patients who received IT morphine (6.8+/-2.8 h) or IT placebo (6.5+/-3.2 h). Four patients who received IT morphine had extubation substantially delayed because of prolonged ventilatory depression. There was no difference between groups in postoperative patient-controlled morphine analgesia use. CONCLUSION: Even when used in conjunction with an intraoperative baseline anesthetic that allows early extubation, IT morphine (10 microg/kg) was unable to provide substantial postoperative analgesia. The risks of using IT morphine in patients undergoing cardiac surgery and early extubation may outweigh the potential benefits.

Hemodynamic effects of methylprednisolone in patients undergoing cardiac operation and early extubation.

BACKGROUND: Whether or not methylprednisolone is beneficial during cardiac operation remains controversial. This study examines the effects of the drug on complement activation and hemodynamics in patients undergoing cardiac operation and early extubation. METHODS: Patients undergoing cardiac operation were randomized to receive either intravenous methylprednisolone (group MP) or intravenous placebo (group NS). Complement 3a (C3a) levels and hemodynamic parameters were obtained perioperatively. Extubation was accomplished at the earliest clinically appropriate time. RESULTS: Both groups exhibited equivalent increases in C3a levels after exposure to bypass. Group MP exhibited increased cardiac index, decreased systemic vascular resistance, and increased shunt flow when compared to group NS. More group MP patients required hemodynamic support and group MP patients had prolonged extubation times. CONCLUSIONS: Methylprednisolone was unable to attenuate complement activation and led to hemodynamic alterations (primarily vasodilation) that may hinder early extubation in patients after cardiac operations.

An institution's initial experience with port-access minimally invasive cardiac surgery.

OBJECTIVE: To assess the learning curve associated with Port-Access minimally invasive cardiac surgery. DESIGN: Retrospective. SETTING: Single university hospital. PARTICIPANTS: Initial 10 patients undergoing Port-Access minimally Invasive cardiac surgery. INTERVENTION: Minimally invasive cardiac surgery. MEASUREMENTS AND MAIN RESULTS: All 10 patients experienced an uneventful intraoperative and immediate postoperative course. Only one patient experienced postoperative cardiovascular morbidity, which was an episode of new-onset atrial fibrillation after mitral valve surgery that was successfully treated with pharmacologic therapy. Extubation times and postoperative discharge times were less than historic controls receiving the same anesthetic technique at the same institution. CONCLUSION: This institution's initial experience with 10 patients undergoing Port-Access minimally invasive cardiac surgery suggests an acceptable learning curve and decreased extubation and postoperative discharge times, which should translate into reduced health care costs.

Pulmonary effects of methylprednisolone in patients undergoing coronary artery bypass grafting and early tracheal extubation.

UNLABELLED: Numerous clinical studies suggest that methylprednisolone may facilitate early tracheal extubation after cardiac surgery, yet no investigation has rigorously examined the use of the drug in this setting. In this prospective, randomized, double-blind, placebo-controlled study, we examined the pulmonary effects of methylprednisolone in patients undergoing coronary artery bypass grafting (CABG) and early tracheal extubation. Sixty patients undergoing elective CABG and early tracheal extubation were randomized into two groups. Group MP patients received i.v. methylprednisolone (30 mg/kg during sternotomy and 30 mg/kg during initiation of cardiopulmonary bypass) and Group NS patients received i.v. placebo at the same two times. Perioperative management was standardized. Alveolar-arterial (A-a) oxygen gradient, lung compliance, shunt, and dead space were determined four times perioperatively. Postoperative tracheal extubation was accomplished at the earliest appropriate time. Both groups exhibited significant postoperative increases in A-a oxygen gradient and shunt (P < 0.000001 for each group) and significant postoperative decreases in dynamic lung compliance (P < 0.000001 for each group). Patients in Group MP exhibited significantly larger increases in postoperative A-a oxygen gradient (P = 0.001) and shunt (P = 0.001) compared with patients in Group NS. Postoperative alterations in dynamic lung compliance, static lung compliance, and dead space were not statistically significant between the groups. The time to postoperative tracheal extubation was prolonged in Group MP patients compared with Group NS patients (769 +/- 294 vs 604 +/- 315 min, respectively; P = 0.05). Methylprednisolone was associated with larger increases in postoperative A-a oxygen gradient and shunt, was unable to prevent postoperative decreases in lung compliance, and prolonged extubation time, which indicate that use of the drug may hinder early tracheal extubation in patients after cardiac surgery. IMPLICATIONS: Traditionally, methylprednisolone has been administered to patients undergoing cardiac surgery to decrease postoperative pulmonary dysfunction. This study revealed that the drug is associated with larger increases in postoperative alveolar-arterial oxygen gradient and shunt and prolonged tracheal extubation time in patients undergoing coronary artery bypass grafting, which indicate that use of the drug may hinder early tracheal extubation.

[Hyperfiltration in diabetic patients]. / Prouchvaniia vurkhu khiperfiltratsiiata pri bolni sus zakharen diabet.

Glomerular filtration and effective renal plasma flow were studied in 24 patients with diabetes mellitus type I (mean age 29.8 +/- 10.5 years) and 20 patients with diabetes mellitus type II (mean age 54 +/- 11 years) and duration of diabetes 5.7 +/- 6 and 11.3 +/- 10 years respectively. There were no clinical signs of nephropathy in all patients studied (the albustick test was negative). The results were compared with those of 30 healthy controls. Out of the 24 patients with diabetes mellitus type I 10 (41%) were with hyperfiltration and from the 20 patients with diabetes mellitus type II only one was with hyperfiltration. The speed of albumin secretion in the diabetic patients with hyperfiltration was 39.9 +/- 42.9 micrograms/min and was significantly higher than that of the diabetic patients without hyperfiltration--26.2 +/- 22.7 micrograms/min. The albuminuria was in a moderate positive correlation with the glomerular filtration. The possible mechanism taking part in the development of hyperfiltration syndrome in diabetes are discussed.

Captopril in treatment of hypertensive diabetic patients. Preliminary study.

This investigation was performed in 15 adult patients: 6 with type I and 9 with type II diabetes mellitus, all with arterial hypertension. Captopril (12.5 to 100 mg daily, mean 34 mg) was administered for a month and was effective as monotherapy in all patients. The supine arterial pressure changed from: 177 +/- 19 mm Hg to 141.7 +/- 7.7 mm Hg systolic and 106 +/- 7.6 mm Hg to 87.3 +/- 5.3 mm Hg diastolic; and upright: from 162.7 +/- 16 mm Hg to 139 +/- 11.4 mm Hg systolic and from 101.7 +/- 11.6 mm Hg to 87.3 +/- 6.5 mm Hg diastolic. The differences were statistically significant (p less than 0.001). The mean blood glucose was changed significantly at the end of the study (from 11.1 +/- 3.4 mmol.l-1 to 8.1 +/- 1.0 mumol.l-1, p less than 0.001), while the daily insulin dose (respectively glybenclamide) remained unchanged. No alterations in serum creatinine, HbA1 (glycohemoglobin), urinary excretion rate of albumin, beta 2-microglobulin, glomerular filtration rate were observed during follow-up. No important change in plasma aldosterone was found, while plasma renin activity was significantly increased (p less than 0.05) as expected. No side effects were reported during the therapy. Captopril appears to be an effective and safe drug for lowering blood pressure in diabetic patients without affecting renal function.

[The correlation of glycohemoglobin (HbA1) with the parameters of blood glucose control during the treatment of diabetes mellitus]. / Korelatsiia na glikokhemoglobina (HbA1) s niakoi parametri na glikemichniia kontrol v khoda na lechenie na zakharniia diabet.

40 diabetic patients (18 patients with diabetes mellitus type I and 22 patients with diabetes mellitus type II) were examined for an average period of 6 months (from 0.5 up to 24 months). The following glycemic parameters were determined: glycohemoglobin (HbA1), average glucose of 6 glucose profiles, fasting glucose, the average of two postprandial glucose concentrations and the M-value. Correlation coefficients between the HbA1 and the parameters studied were determined. In the course of suitable treatment all patients' data were significantly improved. High correlation coefficients were found between HbA1 and the average of the two postprandial glucose concentrations and between HbA1 and the M-value (r = 0.61 and r = 0.60 respectively). The average profile glucose, the average of two postprandial glucose concentrations and the M-value show as reliable parameters for a long-term control compared with the most reliable index HbA1.

[The level of glycosylated hemoglobin in obese patients]. / Nivo na glikiraniia khemoglobin u bolni sus zatlustiavane.

The glycosylated hemoglobin level was examined in 37 obese patients without manifested diabetes mellitus. The level was in the reference ranges. The patients who had lowered carbohydrate tolerance showed a tendency toward a higher glycohemoglobin level. The reduction of body mass was accompanied by a decrease of glycohemoglobin.