Poly(L-DOPA)-mediated bimetallic core-shell nanostructures of gold and silver and their employment in SERS, catalytic activity, and cell viability

Core-shell gold nanorod (AuNR)@silver (Ag) nanostructures with their unique properties have gained enormous interest and are widely utilized in various applications including sensor systems, catalytic reactions, diagnosis, and therapy. Despite the recent progress, simple, effective, low-cost, and easy-to-tune strategies are heavily required to fabricate these nanoparticles (NP) systems. For this, we propose the employment of the polymer of 3,4-dihydroxyphenyl-L-alanine (L-DOPA) as a ligand molecule. A conformal thin layer of polymer of L-DOPA (PLDOPA) with its various functional groups enabled the reduction of silver ions onto the AuNRs and stabilization of the resultant NPs without using any surfactant, reducing agent, and seed material. The shape and growth model of the AuNR@Ag nanostructures was manipulated by simply tuning the amount of silver ions. This procedure created different NP morphologies ranging from concentric to acentric/island shape core-shell nanostructures. Also, even at the highest Ag deposition, the PLDOPA layer is still conformally present onto the Au@Ag core-shell NRs. The unique properties of NP systems provided remarkable characteristics in surface-enhanced Raman spectroscopy, catalytic activity, and cell viability tests.

Effects of Betaxolol and Latanoprost on Ocular Blood flow and Visual Fields in Patients with Primary Open-Angle Glaucoma

Purpose

To evaluate the effects of betaxolol and latanoprost on ocular blood flow and visual fields in patients with primary open-angle glaucoma (POAG) by means of an obseiver-masked, prospective clinical study.

METHODS

Thirty-two patients with newly diagnosed POAG were included in the study. The patients were randomized into two groups. The first group was treated with betaxolol 0.50% twice daily and the second group with latanoprost 0.005% once daily. Baseline and post-treatment examinations on the first and third months of treatment included intraocular pressure (IOP) measurement, automated visual field testing, and ocular blood flow assessment. For evaluation of visual fields, mean defect and pattern standard deviation indices were used. Ocular blood flow was assessed by means of color Doppler imaging of the central retinal artery (CRA) and the temporal short posterior ciliary artery (PCA). For each vessel, peak systolic (PSV) and end-diastolic (EDV) blood flow velocities were measured and resistivity index (RI) calculated.

Results

After exclusion of one noncompliant patient, the study was completed with 31 eyes of 31 patients. Both drugs significantly reduced IOP (p<0.05). The mean IOP lowering effect of latanoprost was significantly higher than that of betaxolol (p=0.03). Visual field indices exhibited no significant changes in either group (p>0.05). There were no significant changes in PSV or EDV measurements of CRA or PCA in either group (p>0.05). RI decreased in both CRA and PCA with both drugs. The mean changes between baseline and 3 month blood flow measurements were not significantly different between betaxolol and latanoprost (p>0.05).

CONCLUSIONS

Over a treatment period of 3 months, both betaxolol and latanoprost tended to improve ocular blood flow without one of them being superior to the other. The results suggest that the direct (non IOP-dependent) influence on ocular circulation is better for betaxolol than for latanoprost. In addition, neither drug caused significant generalized improvements in visual fields during this period.

Direct and protective effects of single or combined addition of vincristine and ε-viniferin on human HepG2 cellular oxidative stress markers in vitro

The objective of this study is to examine the direct effects of low doses and high doses of ε-viniferin, a substance known to be an antioxidant, and vincristine sulphate, a chemotherapeutic agent, alone and in combination [ε-viniferin + vincristine] on HepG2 cell strain, as well as evaluate oxidative stress after incubation periods of 3, 6, and 24 h. Direct effect was determined right after the incubation period; however, for protective effect, antioxidant protection response was determined after the treatment for 1 h with 500 μM H2O2, which is an oxidative stressor. For this purpose, superoxide dismutase was determined for enzyme activity, and lipid hydroperoxide (LPO) and reduced glutathione concentrations were studied as indicators of oxidative stress. Results show that low [3.63 µM vincristine + 3.75 µM ε-viniferin] and high [11.25 µM vincristine + 15.8 µM ε-viniferin] doses of combination groups showed similar direct antioxidant effect on LPO levels as protective when compared to the H2O2 control group (p < 0.05). Superoxide dismutase enzyme showed a direct antioxidant effect in low and high dose combination groups. In addition, when the incubation period was increased to 24 h, a protective effect was observed in both dose groups (p < 0.05). Reduced glutathione activities showed a direct effect in the low dose combination group, and a protective effect in both the low and high doses in the 24 h. These results show that combined usage of drugs in HepG2 cell strain possesses a protective effect against exogenically produced oxidative stress conditions.

MRI Findings of Globe and Optic Nerves in Tilted Disk Syndrome

We assessed the anatomical variations of the globe and optic nerve in tilted disk (TD) syndrome using magnetic resonance imaging (MRI) findings and compared them with a control group. Eleven patients diagnosed with TD syndrome during eye examination were referred for MRI of the sella and chiasm to exclude intracranial mass lesions. The shape of the globe, the chiasmal angle, the insertion angles of the optic nerve in axial and parasagittal planes determined by lines parallel to the optic nerve and tangent to the globe in TD syndrome were compared with a control group consisting of 53 cases. Gender ratios were 7/4 (F/M) for the TD group and 35/18 for the control group (p>0.05). The insertion angle of the optic disk to the globe was wider in the temporal quadrant (p<0.05) and narrower in the nasal quadrant (p<0.05) in TD syndrome than in the control group. There was no significant difference in the superior and inferior insertion angles between the groups. The anterior-posterior (AP) diameter of the globe was significantly longer in patients with TD (p<0.05). There was no significant difference between the optic chiasm angles.

The relationships of the optic disk and the globe were significantly different in patients with TD syndrome in comparison to the control group. TD syndrome is related to the malalignment of optic nerve and globe in the horizontal plane.

Assessment of fetal cerebral arterial and venous blood flow before and after vaginal delivery or Cesarean section

OBJECTIVES

To compare perinatal intracranial arterial and venous blood velocity changes between healthy term neonates delivered vaginally or by Cesarean section and to correlate these changes with cord blood gases and pH values at birth.

METHODS

The study involved 43 healthy term neonates who were delivered vaginally (n = 20) or by Cesarean section (n = 23). All fetuses/neonates were examined by Doppler ultrasound to obtain middle cerebral artery (MCA) and cerebral transverse sinus (Tsin) Doppler waveforms on three occasions (before delivery, and 1 h and 24 h after birth). Pulsatility index (PI) and peak systolic velocity (PSV) for MCA and Tsin were measured and compared between neonates who were delivered vaginally or by Cesarean section. Umbilical cord blood samples were analyzed for umbilical artery and vein pH, pO(2) and pCO(2) and values were correlated with MCA and Tsin Doppler indices.

RESULTS

MCA-PI increased and MCA-PSV decreased at 1 h after birth, and Doppler measurements returned to predelivery values at 24 h after birth. Tsin Doppler measurements remained unchanged at 1 h and 24 h when compared to predelivery values in both the Cesarean and vaginal delivery groups. There was a negative correlation between Tsin-PI before birth and umbilical venous pH. There was a positive correlation between Tsin-PSV at 1 h after birth and umbilical vein pCO(2).

CONCLUSIONS

Cerebral arterial blood velocity decreases immediately after birth and increases within 24 h, probably as part of neonatal adaptation. Cerebral venous blood velocity remains constant during the perinatal period and is likely to be regulated in a different and more complex manner than that of arterial blood velocity. Mode of delivery does not affect cerebral blood velocity.

Magnetic resonance imaging and ultrasonographic evaluation of the patients with knee osteoarthritis: a comparative study

The objectives of the present work were (1) to establish the prevalence of the abnormalities detected by magnetic resonance imaging (MRI) and ultrasonography (US); and (2) to compare these imaging techniques in detail. The study group consisted of 58 patients with symptomatic knee OA and 16 volunteer control subjects. Knee joint was evaluated for femoral condylar cartilage changes, effusion, synovial thickening and popliteal cysts using MRI and US. All knees with OA had cartilage abnormalities on US examinations and normal cartilage was detected in less than 3% of these knees by MRI. Majority of the knees with OA had effusion using US (70%) or MRI (85%). Synovial thickening observed on US (34%) and MRI (50%) were common in the knees with OA. Popliteal cysts were detected in 40% of the knees with OA using US and 35% using MRI. This study confirmed that there was a significant correlation between the MRI and US techniques for evaluating the cartilage and soft tissue changes in the patients with knee OA. There were more significant differences between the controls and the symptomatic knees which had Kellgren-Lawrence (K-L) grade 2 or more OA for the cartilage and soft tissue abnormalities on MRI and US. The prevalence of cartilage changes, effusion, synovial thickening and popliteal cyst using MRI and US were increased as the radiographic grade of OA increased. US examinations could be an alternative to initial evaluation tool to MRI in patients with knee OA.

Relationship between ossification of the stylohyoid ligament and enthesopathy: a comparative study

OBJECTIVE

Stylohyoid apparatus might be an anatomic region in the cervical spine involved by enthesopathy. The aim of this study was to assess the elongation and/or ossification at the stylohyoid apparatus in the degenerative or inflammatory diseases such as ankylosing spondylitis (AS), psoriatic arthropathy (PsA) and cervical spondyloarthrosis (CS) in which cervical spine involvement can be seen.

METHODS

Twenty-eight patients with AS, 25 patients with PsA, 31 patients with CS and 50 controls who did not have any complaints or symptoms related with elongated styloid process (SP) were included in the study. On the lateral cervical radiographs, the anterior and posterior aspects of each vertebral body and intervertebral disk were carefully evaluated for the presence and severity of syndesmophytes, osteophytes or ossification of the adjacent longitudinal ligaments in the patient group. The entire osseous length of the SP was measured on the lateral and lateral oblique mandibular or cervical views or the anteroposterior views radiographs in the patients and controls.

RESULTS

There were statistically significant differences between the patients with AS and control group and between the patients with PsA and control group with respect to the length of SP. The dimension of syndesmophytes or ligamentous ossification of the cervical spine involving C5-6 intervertebral disk level were significantly correlated with length of SP in the patients with AS.

CONCLUSION

Elongated SP might be another manifestation of enthesopaty in cervical spine of the spondyloarthropathies.

Familial pathologic myopia, corneal dystrophy, and deafness: a new syndrome

BACKGROUND

Numerous syndromes with myopia and hearing loss have been described up to now. We present a family with pathologic myopia, corneal dystrophy, and deafness distinct from these syndromes.

CASES

Ten patients in the same Turkish family were evaluated by ophthalmologic, audiologic, physical, radiologic, genetic, serologic, and biochemical examinations.

OBSERVATIONS

Ophthalmic examination indicated that all the cases had myopia, 7 of them had pathologic myopia, 1 had intermediate, and 2 had mild. Four of the patients with pathologic myopia had corneal dystrophy that was bilaterally manifest as white opacities in the posterior stroma near Descemet's membrane in an axial distribution; 1 of these 4 patients also had a tilted disc. Otolaryngologic examination revealed conductive hearing loss in 3 cases, mixed hearing loss in 2, and sensorineural hearing loss in 1. The results of karyotypic analyses of all cases were normal. The pedigree analysis showed the disease was inherited through successive generations as an autosomal dominant trait. The results of biochemical, serologic, and radiologic investigations were normal. The same pathophysiologic process in all cases seemed to account for the myopia, the corneal dystrophy and the deafness.

CONCLUSIONS

To our knowledge, this type of case has not been reported in the literature. Therefore, we named this syndrome "familial pathologic myopia, corneal dystrophy and deafness."

Radiologic anatomy of the sphenoid sinus for intranasal surgery

Endoscopic surgery of the sphenoid sinus can present the operator with a considerable challenge. The relationship of the sphenoid sinuses, in particular on the lateral wall, to the carotid artery, optic nerve, as well as the other anatomic structures, is of utmost importance. Surgical complications can occur because of a lack of orientation during dissection. To avoid the complications or lessen, somehow, the rate of complications, some described the technique consisting of the opening of the sphenoid sinus ostium medially. We studied 69 axial high resolution computed tomography (HRCT) of temporal bones to reveal the relationship of sphenoid sinus to the vital structures and to get some measurements in the sphenoid sinus. The lateral distance from the sphenoid ostium revealed that the lateral distance was about the distance between both ostea. We consider that in selected cases the dissection might be carried out laterally from the sphenoid ostium for safe enlargement of the ostium and approaching the sinus.

Organized hematoma of the maxillary sinus mimicking tumor

The authors present two cases of organized hematoma of the maxillary sinus. Both patients showed no bleeding abnormalities. Clinical symptoms, signs and radiologic appearance of the mass mimicked tumor during the initial diagnosis of the disease. To our knowledge, this is the first article describing organized hematoma in the maxillary sinus mimicking tumor without bleeding history and disorders. A provisional diagnosis of organized hematoma should be considered when a patient with history of epistaxis develops a slow-growing mass of the cheek and/or nasal obstruction.

Morphometric analysis of anatomical relationships of the facial nerve for mastoid surgery

Surgical anatomical relationships of the facial nerve (FN) with several landmarks used in mastoid surgery were studied in temporal bone axial high resolution CT scans of 90 patients (180 ears). The shortest distances between the FN and external auditory canal (EAC), sigmoid sinus (SS), posterior fossa dural plate (PFD), and joint of the bony EAC with the lateral surface of the mastoid (M) were measured. These measurements were also analysed in respect of pneumatization and side differences. On average, it was found that FN-EAC was 2.9 mm, FN-SS was 10.5 mm, FN-PFD was 7.3 mm and FN-M was 15.3 mm. FN-EAC was found to be longer in poorly pneumatized bones whereas other distances were longer in pneumatized bones. FN-M was found to be longer on the right side.

Injury to the lacrimal apparatus after endoscopic sinus surgery: surgical implications from active transport dacryocystography

In order to evaluate the lacrimal drainage system injury after functional endoscopic sinus surgery, surgical records and postoperative active transport dacryocystography imaging of 31 patients were analyzed. Presence of the lacrimal bone dehiscence and no passage of the contrast material into the inferior meatus were noted as the signs of injury to the lacrimal canal on active transport dacryocystography. Bony dehiscence was detected in 53.2% of the operated sides but 20% of the nonoperated sides. No passage of the contrast material into the inferior meatus was observed in 14.9% of the operated sides. There were no cases of epiphora postoperatively. The lacrimal drainage system injury was more frequently observed on the left sides operated. We conclude that lacrimal drainage system injury might occur in various extents during functional endoscopic sinus surgery. However, it does not necessarily result in postoperative epiphora. Performing the middle meatal antrostomy in posteroinferior direction, and uncinectomy with backbiting forceps or a shaver might help in reducing the lacrimal injury. Active transport dacryocystography can be adopted as an alternative diagnostic tool in detection of the lacrimal injury.

Toxicity effects of compressed and supercritical solvents on thermophilic microbial metabolism

Selection of biocompatible solvents is critical when designing bioprocessing applications for the in situ biphasic extraction of metabolic end-products. The prediction of the biocompatibility of supercritical and compressed solvents is more complicated than for liquid solvents, because their properties can change significantly with pressure and temperature. The activity of the anaerobic thermophilic bacterium, Clostridium thermocellum, was studied when the organism was incubated in the presence of compressed nitrogen, ethane, and propane at 333 K and multiple pressures. The metabolic activity of the organisms in contact with compressed solvents was analyzed using traditional indicators of solvent biocompatibility, such as log P, interfacial tension, and solvent density. The toxicity of the compressed solvents was compared with the phase and molecular toxicity effects measured in liquid alkanes at atmospheric pressure. Inactivation increased with time in the presence of the compressed solvents, but was constant in the presence of atmospheric liquid solvents. Knowledge of molecular and phase toxicity provides a framework for the interpretation of C. thermocellum metabolism in contact with atmospheric and compressed solvents.

Endoscopic dacryocystorhinostomy without stents

OBJECTIVE

The aim of this study is to present our endoscopic DCR operation method without the use of silicone tubing and our results on the patients suffering from chronic epiphora with postsaccal stenosis.

METHODS

Endoscopic dacryocystorhinostomy operations were performed to 21 sides of 18 patients who had chronic epiphora. No silicone tubing was used in any of the cases. In the postoperative healing period, the rhinostomy opening was maintained with frequent removal of nasal debris and using eyedrops. The patients were evaluated by fluoresceine test and endoscopic controls.

RESULTS

Symptomatic improvement was achieved in 19 out of 21 sides of the patients (90.5%) and the results were confirmed by the fluoresceine test under endoscopic control.

CONCLUSION

Our results of 21 sides of 18 cases underwent primary DCR without stents are as successful as those reported in the literature and the technique seems to be promising.

Axial length measurement and asteroid hyalosis

PURPOSE

To evaluate the effect of asteroid hyalosis on automated and manual A-scan axial length measurements.

SETTING

Celal Bayar University School of Medicine, Manisa, Turkey.

METHODS

A case-control study comprised 15 patients with unilateral asteroid hyalosis. The uninvolved eyes were used as controls. Axial length measurements by manual and automated A-scan biometry were performed in both eyes. The main outcome measures were comparisons between manual and automated measurements in asteroid hyalosis eyes with those in control eyes and the assessment of density of asteroid bodies on B-scan photographs.

RESULTS

Statistical analysis revealed no significant difference between axial lengths of asteroid hyalosis eyes and those in control eyes with automated (P = .524) or manual (P = .163) methods. Using automated biometry, 1 patient (7%) had a false (6.23 mm) short axial length measurement in the eye with asteroid hyalosis. There were no significant correlations between manual versus automated measurement differences and the density of the asteroid bodies.

CONCLUSIONS

The axial length of the eye without asteroid hyalosis can be used to calculate intraocular lens power if the patient has no history of clinical anisometropia.

Study of direct variable anesthesia costs in the dilatation and curettage patient

This retrospective study was designed to compare the cost of anesthesia in three different groups of patients who received general anesthesia for a diagnostic dilatation and curettage procedure. The analysis included 194 patients, ASA physical status I, II, or III. All patients were outpatients with similar body mass index and age. The three groups were thiopental/isoflurane (n = 13), propofol/isoflurane (n = 126), and propofol/desflurane (n = 55). Anesthesia drugs, volatile agents, personnel costs, and type of providers were included in the cost comparison. The cost of supplies, inhalation agents, and drugs for the thiopental/isoflurane group were significantly different (P < .001) than the other two groups. The mean +/- SD thiopental/isoflurane combination was $7.00 +/- $2.74, whereas, the mean +/- SD cost of the propofol/isoflurane and propofol/desflurane groups was $12.73 +/- $3.57 and $14.40 +/- $5.05, respectively. The mean +/- SD cost of all three anesthetic drugs/volatile agents/endotracheal tube groups was $12.85 +/- $4.35. No statistically significant differences between the three groups were found in postanesthesia care unit (PACU) drug costs, anesthesia personnel cost, total direct anesthesia costs, or length of stay. The incidence of antiemetic administration intraoperatively and in PACU was significantly different (P < .001) between the thiopental/isoflurane group and the other groups. The thiopental/isoflurane group did not receive any antiemetics in either area, whereas the propofol groups received antiemetics 12.7% of the time. The three anesthesia providers, Certified Registered Nurse Anesthetists, student registered nurse anesthetists (SRNA), and anesthesia residents were reviewed looking at anesthesia supply cost, personnel cost, and total direct anesthesia costs. No statistically significant differences were found between the groups. We conclude that an anesthetic using thiopental/isoflurane is more cost-effective than propofol/desflurane or propofol/isoflurane anesthetics and the postoperative length of stay is no different for the three anesthetic approaches.

Hypernatriuria and kaliuresis in enuretic children and the diurnal variation

PURPOSE

We investigate the underlying pathophysiological cause of primary nocturnal enuresis by comparing electrolyte alterations in urine samples of enuretics during the daytime and nighttime compared with those of nonenuretic subjects.

MATERIALS AND METHODS

Urine output, urine specific gravity and urinary electrolytes in 15 enuretic and 12 nonenuretic children were measured. We collected daytime serum and urine samples of children fed a similar diet between 7 a.m. and 7 p.m., and nighttime between samples 7 p.m. and 7 a.m. Urinary calcium/creatinine ratio, tubular reabsorption of phosphorus and excretions of fractional sodium and potassium were calculated.

RESULTS

There was no significant difference between the calcium/creatinine ratio ratios. There was a significant increase in fractional sodium and fractional potassium values in enuretics compared to nonenuretics during the day and at night. Daytime and nighttime fractional sodium and fractional potassium values in enuretics were similar. In contrast to nonenuretics, enuretic patients had no diurnal variation of fractional sodium. There was significant positive correlation between bedwetting status, and fractional sodium and fractional potassium.

CONCLUSIONS

Since sodium and potassium excretions were higher in enuretic patients than nonenuretic children, and no significant diurnal variation in urinary excretion of these ions there might be a difference in the mechanism of reabsorption of sodium and potassium between enuretic and nonenuretic children.

Renal functions of enuretic and nonenuretic children: hypernatriuria and kaliuresis as causes of nocturnal enuresis

OBJECTIVE

The aim of this study was to investigate the pathophysiologic cause(s) of primary nocturnal enuresis. Therefore, electrolyte concentrations of urine specimens were evaluated in the morning, and alterations compared between enuretics and nonenuretics.

METHODS AND PATIENTS

First morning urine specimens of 27 enuretics and 21 nonenuretic subjects fed the same diet were collected, and urinary electrolytes were measured. The urinary Ca/Cr ratio, tubular reabsorption of phosphorus (TRP) and fractional sodium (FE Na%) and potassium excretions (FE K%) were determined for patients and controls.

RESULTS

There was no significant difference in the Ca/Cr ratio and TRP between patients and controls, but enuretic patients had significantly higher FE Na% and FE K% values than controls (p < 0.001). There were significant positive correlations between FE Na% and (r = 0.81, p < 0.001) FE K% and the frequency of bedwetting, respectively, among enuretic patients (r = 0.54, p < 0.001).

CONCLUSION

Since Na and K excretion of enuretic patients was higher than in nonenuretics, it can be concluded that there may be a benign hereditary and/or postural renal tubular handling disorder of Na and K in enuretic children.

Eight year's experience with automated anesthesia record keeping: lessons learned--new directions taken

For the past eight years, an automated anesthesia record keeping system, COMANDAS (COMputerized ANesthesia Data Acquisition System) has been used in the cardiovascular operating rooms at Mayo Clinic. The automated anesthesia record is designed to match the traditional hand-written record and becomes part of the official medical record. COMANDAS is interfaced with the physiologic monitor and mass spectrometer in each OR, and a number of other computers within the Mayo Medical Center. Since the introduction of COMANDAS over 24,000 surgical procedures have been charted. The anesthesia record is more complete, consistent in organization, and legible when compared to a hand-written record. Recently, it was determined that the computers and peripherals that make up COMANDAS were wearing out and that the vendors would no longer support or replace the equipment. A process to find a replacement for COMANDAS was then begun. Although the cardiovascular anesthesia group was satisfied with the automated anesthesia record, there were a number of areas in which improvement was desired. A systematic evaluation of the system was begun with a survey of the users. The majority of those surveyed felt that COMANDAS was a useful system which made parts of their job easier. The user interface, method of manual data entry, time to produce the record and difficulty learning the system were the source of the greatest dissatisfaction. Artifacts, networking, interfacing with other devices and computers were also issues for the replacement system. Most commercial systems were found wanting in one or more areas of significance. The most practical solution appeared to be the modification of a currently available intensive care unit patient data management system.

Anesthetic considerations for aortocoronary bypass graft surgery

Between 1964 and 1978, aortocoronary bypass graft procedures were performed in more than 300,000 patients, and the number seems to increase every year. Nevertheless, the procedure itself can result in perioperative myocardial infarction leading to death. Greater understanding of and constant attention to the myocardial oxygen (O2) supply and demand may reduce the incidence of perioperative myocardial infarction. Some of the factors influencing supply and demand can be controlled pharmacologically. Drugs such as nitroglycerin, nitroprusside, and propranolol can reduce the myocardial O2 demand. Unfortunately, there are few data to elucidate the relationship between myocardial O2 demand and supply as influenced by anesthetic drugs, especially in patients with myocardial ischemia. However, enthusiasm for aortocoronary bypass graft operations has given enormous impetus to laboratory and clinical studies of this subject. Recent developments in anesthetic management afford better means for protection of the ischemic myocardium during and after operation.

Myocardial reinfarction after anesthesia and surgery

During the years 1974 and 1975 at our institution, 587 patients who had suffered previous myocardial infarctions underwent anesthesia and surgery. Thirty-six (6.1%) had a reinfarction and 25 (69%) died. Patients operated on within three months of the previous infarction had a 27% reinfarction rate. This decreased to 11% if the infarct had occurred three to six months previously and stabilized at 4% to 5% if the interval was more than six months. Risk factors associated with significantly increased reinfarction rates included preoperative hypertension, intraoperative hypotensive episodes, and noncardiac thoracic or upper abdominal operations of more than three hours' duration. Time under anesthesia was strikingly correlated with reinfarction rates in the entire group. Postoperative intensive care unit admission did not significantly affect the reinfarction rate, nor did diabetes, angina, patient age or sex, or site of the previous myocardial infarction.

Discontinuing anticoagulant therapy in surgical patients with cardiac valve prostheses. Observations in 180 operations

Between 1962 and 1975, a total of 159 patients with previously implanted man-made cardiac valve prostheses underwent 180 subsequent noncardiac operations at Mayo Clinic. All of these patients were receiving anticoagulants. The overall incidence of their documentable thromboembolic complications was approximately 10%. None of the postoperative complications occurred while the patient was in hospital, with the earliest such complication seen two years later. Patients receiving anticoagulants on a long-term basis did, however, have a 13% incidence of various difficulties with hemostasis during and following the later operations. We conclude that there is minimal risk to patients with cardiac valve prostheses who are receiving anticoagulants when the drug regimen is stopped for one to three days preoperatively and one to seven days postoperatively.

Efficacy of dopamine, dobutamine, and epinephrine during emergence from cardiopulmonary bypass in man

Hemodynamic effects of dobutamine and dopamine (both 5, 10, 15 microgram/kg/min) and epinephrine (0.04 microgram/kg/min) were studied immediately following cessation of cardiopulmonary bypass in 34 patients with preoperative evidence of left ventricular dysfunction. Significant increases in mean cardiac index were seen with dobutamine (15, 25, and 26% respectively), and epinephrine (30%). The largest increases occurred with dopamine (44, 53, and 64 percent respectively). Responses varied from patient to patient, however. Seven patients developed marked output increases without concomitant increases in arterial pressure, whereas seven others showed "satisfying" increases in arterial pressure without appreciable output increases. Heart rate increases were small and few arrhythmias were noted. We conclude that dopamine, epinephrine, and dobutamine all are effective inotropic agents during the immediate post-bypass period, with variations discussed in detail. None possess the disturbing chronotropic and arrhythmogenic effects of isoproterenol (previously studied). Efficacy of administration of inotropic drugs seems best assessed by serial output measurements during this period.

Myocardial infarction after general anesthesia

During 1967 and 1968, a total of 32,877 patients had general anesthesia at the Mayo Clinic; 422 had previous myocardial infarction. Of these 6.6% experienced another infarction during the first postoperative week. There was no relationship between incidence of postoperative reinfarction and type or duration of anesthesia. However, operations on the thorax and upper abdomen were followed by three times as many reinfarctions as operations at other sites. Patients who were operated on within three months of infarction had a 37% reinfarction rate. This rate decreased to 16% in patients at three to six months after infarction, and remained at 4% to 5% when infarction had occurred more than six months previously. A significantly higher number of myocardial infarctions occurred during the third postoperative day.

Anesthesia and postoperative care for cardiac operations

Almost three decades have passed since the establishment of open-heart surgery, and in such a short life span the specialty has established itself scientifically and reached a certain maturity. New techniques, better understanding of the pathophysiology of cardiac problems, and the effective use of new drugs constantly improve the results of operation. Greater experience in anesthetic management and improved postoperative care will contribute much to the success of this youngest surgical specialty. This review outlines the current principles of anesthesia and postoperative care of patients undergoing cardiac operations. Preanesthetic evaluation provides guidance for anesthetic management, supportive techniques, and postoperative care. During operations, light anesthesia is usually sufficient for patients with cardiac disease and minimizes myocardial depression. Monitoring must provide data on the physiological changes that are taking place from moment to moment during and after operations. Perfusion produces a highly abnormal state, and the severity of complications varies with its duration. Introduction of new drugs has also facilitated hemodynamic management during and after operations. Postoperative care is based on careful observation of the patient and early detection of trends, both of which lead to preventive rather than curative treatment wheneven possible.

Dobutamine for inotropic support during emergence from cardiopulmonary bypass

Dobutamine, a recently introduced derivative of dopamine, is reported to retain inotropic properties with less pronounced chronotropic and arrhythmogenic effects than isoproterenol. The drug was evaluated in two doses, 5 mug/kg/min and 10 mug/kg/min, in two groups of ten patients each, during emergence from cardiopulmonary bypass. A third group of five patients was studied similarly with isoproterenol, 0.02 mug/kg/min. Cardiac index increased 16 and 28 per cent eith the two doses of dobutamine, respectively, and 9 per cent with isoproterenol. Heart rate, in contrast, increased 6 and 15 per cent with dobutamine (not significant) and 44 per cent with isoproterenol (significant). Dobutamine seemed to associated with fewer arrhythmias than isoproterenol. It is concluded that dobutamine, 5-10 mug/kg/min, is suitable for use during emergence from cardiopulmonary bypass and may possess advantages over isoproterenol.

Hemodynamic effects of morphine during and early after cardiac operations

Hemodynamics and blood gases were measured before and 15 minutes after small (10 mg/70 kg) doses of intravenously administered morphine in two groups of patients having open heart surgery. In one group, the study was undertaken after median sternotomy but before perfusion. The other group had been in the intensive care unit for approximately 1 hour. No changes were found in either group in cardiac index, atrial pressures, arterial pressure, or blood gas variables. However, mean systemic vascular resistance decreased from 41.5 to 35.4 after morphine was given postoperatively. Hence, hemodynamically, morphine is a safe drug if given in small doses for pain relief and sedation early after open heart surgery.

Hemodynamic effects of isoflurane and halothane in patients with coronary artery disease

In 12 patients undergoing saphenous vein coronary artery bypass operations, cardiovascular hemodynamics were studied in the awake state (control) and during anesthesia with isoflurane (inspired concentration, 1.24%, 7 patients) or with halothane (inspired concentration, 0.77%, 5 patients). Isoflurane anesthesia was accompanied by decreases of 19% in the cardiac index (Q), 19% in mean arterial pressure (AP), and 16% in heart rate (HR). Only the change in AP was statistically significant. Halothane anesthesia was accompanied by decreases in Q (28%), AP (22%), and HR (10%). The changes in Q and AP were significant. HR did not change significantly following the induction of anesthesia with either agent. The decrease in AP was similar with both agents, and, in this regard, neither agent was clearly superior for patients with occlusive coronary artery disease.

Circulatory effects of vagal inflation reflex in man

In five patients studied during cardiopulmonary bypass, lung inflation had no effect on heart rate or on total peripheral resistance. Changes of heart rate could be induced my manipulation of the right or left atrium.

Failure of transfusion of autologous whole blood to reduce banked-blood requirements in open-heart surgical patients

Although transfusion of autologous blood by the method described would seem to be a safe and proctical means of reducing banked-blood requirements for open-heart operations, our experience indicates that the amount of blood needed to be added to the pump oxygenator more than negates the value in reducing intraoperative blood requirements. In fact, autologously transfused patients used more blood than did control subjects. Platelet and fresh-frozen plasma administration was not significantly different for the autologous transfusion or control group.