Central Versus Peripheral Arterial Cannulation for Veno-Arterial Extracorporeal Membrane Oxygenation in Post-Cardiotomy Patients.

Different arterial cannulation strategies are feasible for veno-arterial extracorporeal membrane oxygenation (VA-ECMO) in postcardiotomy shock. We aimed to analyze potential benefits and safety of different arterial cannulation strategies. We identified 158 patients with postcardiotomy cardiogenic shock requiring VA-ECMO between 01/10 and 01/19. Eighty-eight patients were cannulated via axillary or femoral artery (group P), and 70 centrally via the ascending aorta directly or through an 8 mm vascular graft anastomosed to the ascending aorta (group C). Demographics and operative parameters were similar. Change of cannulation site for Harlequin's syndrome or hyperperfusion of an extremity occurred in 13 patients in group P but never in group C (p = 0.001). Surgical revision of cannulation site was also encountered more often in group P than C. The need for left ventricular (LV) unloading was similar between groups, whereas surgical venting was more often implemented in group C (11.4% vs. 2.3, p = 0.023). Stroke rates, renal failure, and peripheral ischemia were similar. Weaning rate from ECMO (52.9% vs. 52.3%, p = NS) was similar. The 30 day mortality was higher in group P (60% vs. 76.1%, p = 0.029). Central cannulation for VA-ECMO provides antegrade flow without Harlequin's syndrome, changes of arterial cannula site, and better 30 day survival. Complication rates regarding need for reexploration and transfusion requirements were similar.

Hydrogel gratings with patterned analyte responsive dyes for spectroscopic sensing.

This is an unprecedented report of hydrogel gratings with an analyte responsive dye immobilised in alternating strips where the patterned dye is its own dispersive element to perform spectroscopy. At each wavelength, the diffraction efficiency of hydrogel gratings is a function of dye absorbance, which in turn is dependent on the concentration of analytes in samples. Thus, changes in intensity of diffracted light of hydrogel gratings were measured for sensing of analytes. Equally, the ratio of diffracted intensities at two wavelengths was used for quantification of analytes to reduce errors caused by variations in intensity of light sources and photobleaching of dyes. 15.27 µm pitch gratings were fabricated by exposing 175 µm thick films of photofunctionalisable poly(acrylamide) hydrogel in a laser interferometric lithography setup, generating an array of alternating lines with and without free functional groups. The freed functional groups were reacted with pH sensitive fluorescein isothiocyanate to create gratings for measurement of pH. The ratio of intensity of diffracted light of hydrogel gratings at 430 and 475 nm was shown to be linear over 4 pH units, which compares favourably with ∼2 pH units for conventional absorption spectroscopy. This increased dynamic range was a result of cancellation of the opposite non-linearities in the pH response of the analyte responsive dye and the diffraction efficiency as a function of dye absorbance.

Simple Endotoxin Detection Using Polymyxin-B-Gated Nanoparticles.

A nanodevice based on mesoporous silica nanoparticles with rhodamine B in the pore framework, functionalized with carboxylates on the outer surface and capped with the cationic polymyxin B peptide, was used to selectively detect endotoxin in aqueous solutions with a limit of detection in the picomolar range.

Chromogenic and Fluorogenic Probes for the Detection of Illicit Drugs.

The consumption of illicit drugs has increased exponentially in recent years and has become a problem that worries both governments and international institutions. The rapid emergence of new compounds, their easy access, the low levels at which these substances are able to produce an effect, and their short time of permanence in the organism make it necessary to develop highly rapid, easy, sensitive, and selective methods for their detection. Currently, the most widely used methods for drug detection are based on techniques that require large measurement times, the use of sophisticated equipment, and qualified personnel. Chromo- and fluorogenic methods are an alternative to those classical procedures.

Impact of Major Pulmonary Resections on Right Ventricular Function: Early Postoperative Changes.

BACKGROUND: Right ventricular (RV) dysfunction after pulmonary resection in the early postoperative period is documented by reduced RV ejection fraction and increased RV end-diastolic volume index. Supraventricular arrhythmia, particularly atrial fibrillation, is common after pulmonary resection. RV assessment can be done by non-invasive methods and/or invasive approaches such as right cardiac catheterization. Incorporation of a rapid response thermistor to pulmonary artery catheter permits continuous measurements of cardiac output, right ventricular ejection fraction, and right ventricular end-diastolic volume. It can also be used for right atrial and right ventricular pacing, and for measuring right-sided pressures, including pulmonary capillary wedge pressure. METHODS: This study included 178 patients who underwent major pulmonary resections, 36 who underwent pneumonectomy assigned as group (I) and 142 who underwent lobectomy assigned as group (II). The study was conducted at the cardiothoracic surgery department of Benha University hospital in Egypt; patients enrolled were operated on from February 2012 to February 2016. A rapid response thermistor pulmonary artery catheter was inserted via the right internal jugular vein. Preoperatively the following was recorded: central venous pressure, mean pulmonary artery pressure, pulmonary capillary wedge pressure, cardiac output, right ventricular ejection fraction and volumes. The same parameters were collected in fixed time intervals after 3 hours, 6 hours, 12 hours, 24 hours, and 48 hours postoperatively. RESULTS: For group (I): There were no statistically significant changes between the preoperative and postoperative records in the central venous pressure and mean arterial pressure; there were no statistically significant changes in the preoperative and 12, 24, and 48 hour postoperative records for cardiac index; 3 and 6 hours postoperative showed significant changes. There were statistically significant changes between the preoperative and postoperative records for heart rate, mean pulmonary artery pressure, pulmonary capillary wedge pressure, pulmonary vascular resistance, right ventricular ejection fraction and right ventricular end diastolic volume index, in all postoperative records. For group (II): There were no statistically significant changes between the preoperative and all postoperative records for the central venous pressure, mean arterial pressure and cardiac index. There were statistically significant changes between the preoperative and postoperative records for heart rate, mean pulmonary artery pressure, pulmonary capillary wedge pressure, pulmonary vascular resistance, right ventricular ejection fraction and right ventricular end diastolic volume index in all postoperative records. There were statistically significant changes between the two groups in all postoperative records for heart rate, mean pulmonary artery pressure, pulmonary capillary wedge pressure, pulmonary vascular resistance, right ventricular ejection fraction and right ventricular end diastolic volume index. CONCLUSION: There is right ventricular dysfunction early after major pulmonary resection caused by increased right ventricular afterload. This dysfunction is more present in pneumonectomy than in lobectomy. Heart rate, mean pulmonary artery pressure, pulmonary capillary wedge pressure, pulmonary vascular resistance, right ventricular ejection fraction, and right ventricular end diastolic volume index are significantly affected by pulmonary resection.

Total Correction of Tetralogy of Fallot at Early Age: A Study of 183 Cases.

BACKGROUND: Opinions regarding the optimal time for the repair of tetralogy of Fallot vary. A debate also exists about the timing of repair for the asymptomatic infant. METHODS: This study included 183 patients with tetralogy of Fallot. All patients were subjected to clinical examination with measurement of oxygen saturation, 12-lead ECG, plain chest x-ray, and complete laboratory investigation. Echocardiography and cardiac catheterisation were indicated if there was an inability to reach diagnosis by echocardiography, suspicion of coronary anomaly, evaluation of distal pulmonary arteries or suspicion of major aorto-pulmonary collaterals. Complete repair was done in all patients. Patients were divided into two groups for comparison. Group 1 (147 patients, 1-year-old or less), and Group 2 (36 patients older than 1 year). RESULTS: Three patients died in Group1 (2.04%) while there was no early mortality in Group 2 patients. Six patients in Group 1 (4.08%) were reoperated for significant residual or recurrent right ventricular outflow stenosis, three patients (2.04%) were reoperated for residual significant shunt, and three patients (2.04%) were reoperated for residual significant stenosis and residual significant shunt. That is in addition to three patients (2.04%) who had significant tricuspid regurgitation, three more patients (2.04%) who needed a permanent pacemaker implantation, and nine patients (6.1%) who had significant postoperative pulmonary valve regurgitation. On the other hand, for Group 2 patients, there were only three patients who were reoperated for postoperative restenosis and significant shunt, three patients who were reoperated for permanent pacemaker implantation, and another two patients who had insignificant restenosis to be followed up. CONCLUSIONS: Early complete tetralogy of Fallot repair can be accomplished with a low mortality.

Capped Mesoporous Silica Nanoparticles for the Selective and Sensitive Detection of Cyanide.

The development of easy and affordable methods for the detection of cyanide is of great significance due to the high toxicity of this anion and the potential risks associated with its pollution. Herein, optical detection of cyanide in water has been achieved by using a hybrid organic-inorganic nanomaterial. Mesoporous silica nanoparticles were loaded with [Ru(bipy)3 ]2+ , functionalized with macrocyclic nickel(II) complex subunits, and capped with a sterically hindering anion (hexametaphosphate). Cyanide selectively induces demetallation of nickel(II) complexes and the removal of capping anions from the silica surface, allowing the release of the dye and the consequent increase in fluorescence intensity. The response of the capped nanoparticles in aqueous solution is highly selective and sensitive towards cyanide with a limit of detection of 2 µm.

Combined pulmonary and left ventricular support with veno-pulmonary ECMO and impella 5.0 for cardiogenic shock after coronary surgery.

BACKGROUND: Mechanical circulatory support is a common practice nowadays in the management of patients after cardiogenic shock due to myocardial infarction. The single or combined use of one or more devices for mechanical support depends not only on the advantage or disadvantage of these devices but also on the timing of use of these devices before the development of multi organ failure. In our case we used more than one tool for mechanical circulatory support during the prolonged and complicated course of our patient with postcardiotomy cardiogenic shock after coronary artery bypass surgery. CASE PRESENTATION: We describe the combined use of Impella 5.0 and veno- pulmonary extra corporeal membrane oxygenation (VP-ECMO) for biventricular failure in a 52 years-old man. He presented with cardiogenic shock after inferior wall ST-elevation myocardial infarction. After emergency coronary artery bypass surgery and failure to wean from extracorporeal circulation we employed V-P ECMO and consecutively Impella 5.0 to manage the primarily failing right and secondarily failing left ventricles. He remained hemodynamically stable on both Impella 5.0 and VP-ECMO until Heart Mate II left ventricular assist device implantation on the 14th postoperative day. Right sided support was weaned on 66th postoperative day. The patient remained in the intensive care unit for 77 days. During his prolonged stay, he underwent renal replacement therapy and tracheostomy with complete recovery. Six months later, he was successfully heart transplanted and has completed three and half years of unremarkable follow up. CONCLUSIONS: The combined use of VP ECMO and Impella 5.0 is effective in the management of postcardiotomy biventricular failure as a bridge for further mechanical support or heart transplantation.

Acetylcholinesterase-capped Mesoporous Silica Nanoparticles Controlled by the Presence of Inhibitors.

Two different acetylcholinesterase (AChE)-capped mesoporous silica nanoparticles (MSNs), S1-AChE and S2-AChE, were prepared and characterized. MSNs were loaded with rhodamine B and the external surface was functionalized with either pyridostigmine derivative P1 (to yield solid S1) or neostigmine derivative P2 (to obtain S2). The final capped materials were obtained by coordinating grafted P1 or P2 with AChE's active sites (to give S1-AChE and S2-AChE, respectively). Both materials were able to release rhodamine B in the presence of diisopropylfluorophosphate (DFP) or neostigmine in a concentration-dependent manner via the competitive displacement of AChE through DFP and neostigmine coordination with the AChE's active sites. The responses of S1-AChE and S2-AChE were also tested with other enzyme inhibitors and substrates. These studies suggest that S1-AChE nanoparticles can be used for the selective detection of nerve agent simulant DFP and paraoxon.

Acetylcholinesterase-Capped Mesoporous Silica Nanoparticles That Open in the Presence of Diisopropylfluorophosphate (a Sarin or Soman Simulant).

Mesoporous silica nanoparticles loaded with rhodamine B and capped with acetylcholinesterase are able to be selectively opened and deliver their cargo in the presence of nerve agent simulant diisopropyl fluorophosphate (DFP).

Anions as Triggers in Controlled Release Protocols from Mesoporous Silica Nanoparticles Functionalized with Macrocyclic Copper(II) Complexes.

Three different mesoporous silica nano-sized materials (SC1, SC2, and SC3), loaded with [Ru(bipy)3 ]2+ dye (bipy=bipyridine) and functionalized on the external surface with three macrocyclic copper(II) complexes (C1, C2, and C3), were synthesized and characterized. When SC1, SC2, and SC3 were suspended in water, the entrapped [Ru(bipy)3 ]2+ dye was free to diffuse from the inner pores to the solution. However, addition of anions induced certain degrees of pore blockage, with subsequent dye release inhibition. Small monovalent and divalent anions were unable to induce complete pore blockage, whereas bulky and highly charged anions induced marked reductions in [Ru(bipy)3 ]2+ delivery. The best [Ru(bipy)3 ]2+ delivery inhibitors were ATP and hexametaphosphate anions. Inhibition was ascribed to the interaction of the anions with the grafted CuII complexes on the surface of the SC1, SC2, and SC3 supports. The hexametaphosphate anion was selected to prepare two capped materials (SC1-mPh and SC3-mPh). Studies of the [Ru(bipy)3 ]2+ dye release from solids SC1-mPh and SC3-mPh alone and in the presence of a collection of selected anions (HS- , F- , Br- , Cl- , I- , CN- , HPO42- , AcO- , citrate, NO32- , HCO3- , SO42- , and S2 O82- ), amino acids (alanine and histidine), thiol-containing biomolecules (cysteine, methylcysteine, homocysteine, and glutathione (GSH)), and oxidants (H2 O2 ) were performed. None of the chemicals tested, except hydrogen sulphide, was able to induce remarkable cargo delivery in both solids. The observed dye release was ascribed to a demetalation reaction of the C1 and C3 complexes induced by the hydrogen sulphide anion.

Chromogenic Detection of Aqueous Formaldehyde Using Functionalized Silica Nanoparticles.

Silica nanoparticles functionalized with thiol reactive units and bulky polar polyamines were used for the selective colorimetric detection of formaldehyde. The reaction of thiols groups in the nanoparticles surface with a squaraine dye resulted in loss of the π-conjugation of the chromophores, and the subsequent bleaching of the solution. However, when formaldehyde was present in the suspension, the thiol-squaraine reaction was inhibited and a chromogenic response was observed. A selective response to formaldehyde was observed only when the thiol and polyamine groups were anchored to the silica surface. The observed selective response was ascribed to the fact that bulky polyamines generate a highly polar environment around thiols, which were only able to react with the small and polar formaldehyde, but not with other aldehydes. The sensing nanoparticles showed a limit of detection (LOD) for formaldehyde of 36 ppb in water.

Hexametaphosphate-Capped Silica Mesoporous Nanoparticles Containing Cu(II) Complexes for the Selective and Sensitive Optical Detection of Hydrogen Sulfide in Water.

Cu(II) -macrocycle functionalized hexametaphosphate-capped silica mesoporous nanoparticles have been prepared and used for the selective and sensitive detection of hydrogen sulfide in aqueous environments. The possibility of using different metal complexes combined with different capping anions and choice of different dyes or other sensing molecules as indicators makes this new protocol highly appealing for the preparation of new sensing systems for sulfide detection in different environments.

Highly selective and sensitive detection of glutathione using mesoporous silica nanoparticles capped with disulfide-containing oligo(ethylene glycol) chains.

Mesoporous silica nanoparticles loaded with safranin O and capped with disulfide-containing oligo(ethylene glycol) chains were used for the selective and sensitive fluorimetric detection of glutathione.

A Chromogenic Probe for the Selective Recognition of Sarin and Soman Mimic DFP.

The synthesis, characterization and sensing features of a novel probe 1 for the selective chromogenic recognition of diisopropylfluorophosphate (DFP), a sarin and soman mimic, in 99:1 (v/v) water/acetonitrile and in the gas phase is reported. Colour modulation is based on the combined reaction of phosphorylation of 1 and fluoride-induced hydrolysis of a silyl ether moiety. As fluoride is a specific reaction product of the reaction between DFP and the -OH group, the probe shows a selective colour modulation in the presence of this chemical. Other nerve agent simulants, certain anions, oxidant species and other organophosphorous compounds were unable to induce colour changes in 1. This is one of the very few examples of a selective detection, in solution and in the gas phase, of a sarin and soman simulant versus other reactive derivatives such as the tabun mimic diethylcyanophosphate (DCNP).

Effect of slow versus rapid rewarming on jugular bulb oxygen saturation in adult patients undergoing open heart surgery.

BACKGROUND: A debate has appeared in the recent literature about the optimum rewarming strategy (slow vs. rapid) for the best brain function. This study was designed to compare the effect of slow versus rapid rewarming on jugular bulb oxygen saturation (SjO2) in adult patients undergoing open heart surgery. MATERIALS AND METHODS: A total of 80 patients undergoing valve and adult congenital heart surgery were randomly allocated equally to rapid rewarming group 0.5 (0.136)°C/min and slow rewarming group 0.219 (0.055)°C/min in jugular bulb sampling was taken before, during and after surgery. Surgery was done at cardiopulmonary bypass (CPB) temperature of 28-30°C and rewarming was performed at the end of the surgical procedure. RESULTS: CPB time, rewarming period were significantly longer in the slow rewarming group. Significant difference was observed in the number of the desaturated patients (SjO2 ≤ 50%) between the two groups; 14 (35%) in rapid rewarming versus 6 (15%) in the slow rewarming group; P = 0.035 by Fisher's exact test. CONCLUSIONS: Slow rewarming could reduce the incidence of SjO2 desaturation during rewarming in adult patients undergoing open heart surgery.

Coronary fistula between the left anterior descending coronary artery and the pulmonary artery: Two case reports.

Coronary artery fistulae are rare congenital or acquired connections between the coronary vessels and the cardiac chambers or other vascular structures. We present two consecutive cases of coronary fistulae between the proximal left anterior descending artery (LAD) and the main pulmonary artery. Both cases where admitted with history of acute coronary syndromes and had multivessel coronary disease along with coronary pulmonary fistulae. The two cases were managed by coronary artery bypass grafting (CABG) and repair of the fistulae.

Intraoperative ventilatory strategies for prevention of pulmonary atelectasis in obese patients undergoing laparoscopic bariatric surgery.

BACKGROUND: Atelectasis occurs regularly after induction of general anesthesia, persists postoperatively, and may contribute to significant postoperative morbidity and additional health care costs. Laparoscopic surgery has been reported to be associated with an increased incidence of postoperative atelectasis. It has been shown that during general anesthesia, obese patients have a greater risk of atelectasis than nonobese patients. Preventing atelectasis is important for all patients but is especially important when caring for obese patients. METHODS: We randomly allocated 66 adult obese patients with a body mass index between 30 and 50 kg/m(2) scheduled to undergo laparoscopic bariatric surgery into 3 groups. According to the recruitment maneuver used, the zero end-expiratory pressure (ZEEP) group (n = 22) received the vital capacity maneuver (VCM) maintained for 7-8 s applied immediately after intubation plus ZEEP; the positive end-expiratory pressure (PEEP) 5 group (n = 22) received the VCM maintained for 7-8 s applied immediately after intubation plus 5 cm H(2)O of PEEP; and the PEEP 10 group (n = 22) received the VCM maintained for 7-8 s applied immediately after intubation plus 10 cm H(2)O of PEEP. All other variables (e.g., anesthetic and surgical techniques) were the same for all patients. Heart rate, noninvasive mean arterial blood pressure, arterial oxygen saturation, and alveolar-arterial Pao(2) gradient (A-a Pao(2)) were measured intraoperatively and postoperatively in the postanesthesia care unit (PACU). Length of stay in the PACU and the use of a nonrebreathing O(2) mask (100% Fio(2)) or reintubation were also recorded. A computed tomographic scan of the chest was performed preoperatively and postoperatively after discharge from the PACU to evaluate lung atelectasis. RESULTS: Patients in the PEEP 10 group had better oxygenation both intraoperatively and postoperatively in the PACU, lower atelectasis score on chest computed tomographic scan, and less postoperative pulmonary complications than the ZEEP and PEEP 5 groups. There was no evidence of barotrauma in any patient in the 3 study groups. CONCLUSIONS: Intraoperative alveolar recruitment with a VCM followed by PEEP 10 cm H(2)O is effective at preventing lung atelectasis and is associated with better oxygenation, shorter PACU stay, and fewer pulmonary complications in the postoperative period in obese patients undergoing laparoscopic bariatric surgery.

Effect of different preoperative patient characteristics on coronary surgery outcome: a comparative study between a developing and a developed country.

OBJECTIVES: To evaluate the impact of the preoperative patient characteristics on the results of coronary surgery in a developing country compared with a developed country. PATIENTS AND METHODS: Preoperative risk factors for coronary artery disease (CAD) and intraoperative and immediate postoperative variables for coronary surgery were compared. Sixty patients were operated at Ain Shams University in Cairo (Egypt) between March and September 1999, compared with 60 patients operated at Hannover medical school (Germany) between March and September 2001. By using univariate analysis and multivariate logistic regression, model predictors for hospital mortality were determined. RESULTS: Groups were comparable regarding a majority of risk factors except age, diabetes, chronic obstructive pulmonary disease (COPD), and hypertension. Seventy percent of the Egyptian patients presented in New York Heart Association (NYHA) class III, whereas 50% of the German patients were in NYHA class II. Fifty percent of the German patients showed left ventricular ejection fraction (LVEF) >60%, whereas 52% of the Egyptian patients had LVEF between 40% and 59%. Diabetes (56.6%) and COPD (43.3%) are the major predictors of hospital mortality among the Egyptian patients as proved by high odds ratio (4.6 and 3.4, respectively). Egyptian patients required prolonged mechanical ventilation and extended intensive care unit and hospital stay. Hospital mortality was 6.7% in the Egyptian versus 1.7% in the German group. CONCLUSION: Diabetes mellitus, COPD, and prolonged mechanical ventilation are the major predictors of hospital mortality in Egypt. This study tries to underline problems of coronary artery bypass graft surgery in different populations.