Robotic totally endoscopic triple coronary artery bypass grafting on the arrested heart: report of the first successful clinical case

Robotic technology enables "port only" totally endoscopic coronary artery bypass grafting (TECAB). During early procedure development only single bypass grafts were feasible. Because current referral practice for coronary bypass surgery mostly includes multivessel disease, performance of multiple endoscopic bypass grafts is desirable. We report a case in which a patient received a right internal mammary artery bypass graft to the left anterior descending artery and a left internal mammary artery jump graft to 2 obtuse marginal branches. The procedure was performed through 5 ports on the arrested heart using the daVinci S robotic surgical system. This is the first reported triple bypass grafting procedure using an arrested heart approach.     

Effect of Prostaglandin E1 on Ischemia–Reperfusion Injury During Abdominal Aortic Aneurysm Surgery

Objective Abdominal aortic aneurysm (AAA) surgery subjects the lower extremities to ischemia and reperfusion. Although it is not extensive or prolonged, ischemia of the lower extremities during aortic cross-clamping is gradually and steadily induced. We studied the effects of prostaglandin E₁ (PGE₁) on ischemia–reperfusion injury of the lower extremities during AAA repair. Methods During AAA surgery, two near-infrared spectroscopy probes were positioned on each calf muscle to monitor oxygen metabolism in the lower extremities. We also measured lactate concentration in both iliac veins. Results Near-infrared spectroscopy signals responded sensitively to aortic cross-clamping and declamping. Lactate increased time-dependently during aortic cross-clamping. The continuous venous administration of PGE₁ (20 ng/kg per minute) inhibited the accumulation of lactate during aortic cross-clamping. Declamping of the first iliac artery resulted in a further but transient increase in ipsilateral venous lactate, which may be one component in the mechanism of declamping shock. Prostaglandin E₁ eliminated the transient increase in ipsilateral lactate. The administration of PGE₁ inhibited the contralateral accumulation of lactate after first declamping, and the lactate level decreased gradually before the second declamping. Conclusions Prostaglandin E₁ seems to have a protective effect against ischemia–reperfusion injury of the lower extremities during AAA surgery.     

Fixation of Kirschner wires: a comparison between hammering and drilling k-wires into ribs of pigs

Kirschner wire (K-wire) fixation is a well-accepted method for stabilization of fractures. However, the rotary drill traditionally used for insertion leads to a considerable amount of complications (33%). Another method for insertion was tested which might possibly reduce these complications—hammering. Forty-four K-wires were inserted into the ribs of pigs using a drilling and a hammering technique. Peak extraction force, peak torque, and insertion time were measured. The mean peak extraction forces for drilling and hammering were 57.4 and 129.0 N, respectively. The mean peak torque for drilling and hammering were 2.4 and 5.7e−02 Nm, respectively. Using the drilling technique, it took 73.6 s to insert the K-wire compared with 18.4 s for hammering. At the exit site, there were splinters of bone in 18 of the 22 hammered K-wires and in 2 of the 22 drilled K-wires. This study showed that hammering K-wires into ribs of pigs gives better initial fixation and results in a shorter insertion time.D.B. van Egmond is deceased.     

Acute subdural hematoma originating from the lacerated intracranial internal carotid arteries--case report

A 51-year-old male presented with laceration of the bilateral intracranial internal carotid arteries (ICAs) manifesting as acute subdural hematoma (SDH) after a fall of 3 m. Brain computed tomography showed acute SDH appearing as irregular mixed high and low density and causing midline shift. During the operation, massive liquiform hematoma flowed out from the deep portion around the cranial base and systemic blood pressure decreased abruptly. Hemostasis was impossible and he died soon after the operation. Autopsy revealed skull fractures in the bilateral sphenoidal, orbital, temporal, frontal, parietal, and occipital bones, and laceration of the bilateral ICAs in the cavernous sinuses at the fracture sites. Acute SDH can be caused by laceration of the ICA.     

Effects of multiple firings on the mechanical properties and microstructure of veneering ceramics for zirconia frameworks

Objectives

The purpose of this study is to evaluate the effects of multiple firings on the mechanical properties and microstructure of veneering ceramics used with zirconia frameworks.

Methods

Five different veneering ceramics for zirconia frameworks were used: Vintage ZR (ZR), Cerabien ZR (CZR), Vita VM9 (VM9), Cercon ceram KISS (KISS), IPS e.max ceram (e.max), and one veneering ceramic used for PFM frameworks: Vintage MP (MP). Twenty specimens were fabricated of each veneering ceramic. Ten specimens were fired twice and another ten specimens were fired ten times. Three-point flexural strength following the ISO 6872 and Vickers hardness were measured, and fracture toughness (K_IC) was calculated. Density and porosity were determined. Specimens were characterized using X-ray diffraction (XRD) and scanning electron microscopy (SEM).

Results

For all materials, density increased and porosity decreased after 10 firings. Significant differences in density and porosity were observed between 2 and 10 firings, with the exception of VM9 (P < 0.05). There were no significant differences in flexural strength between 2 and 10 firings except for MP. The Vickers hardness of ZR, VM9, KISS and MP increased significantly after 10 firings (P < 0.001). There were no significant differences in fracture toughness for ZR, CZR, VM9 and MP between 2 and 10 firings. However, e.max underwent a significant increase in fracture toughness (P = 0.000), and there was a significant decrease in the toughness of KISS after 10 firings (P = 0.007).

Conclusion

Multiple firings could be effective for improving the densification and the hardness of veneering ceramics for zirconia restorations.

Clinical significance

By 10 firings, the density and hardness of the veneering ceramics used with zirconia frameworks were raised, and porosity was reduced. However, no significant changes occurred in flexural strength, fracture toughness or microstructure.     

Measurement of airway resistance in anesthetized and paralyzed subjects: Proposal for evaluation of K1 values

The effects of lung volume and respiratory airflow on airway resistance were studied in five anesthetized and paralyzed patients. Airway resistance measured during the inspiratory phase with intermittent constant airflow inflatoins decreased in inverse correlationship to increases in lung volume. Airway resistance measured during the expiratory phase with an airway interruption technique, on the other hand, increased with a linear relationship to the expiratory airflow as expressed by a function of Y = K₁ + K₂X. K₁, calculated from the values of airway resistance corresponding to three different airflows, was unaffected by intentional expiratory resistance loading. Thus, simultaneously with the measurement of airway resistance by this method, expiratory gas sampling with a Douglas bag can be done if necessary. Since the K₂ value of the endotracheal tube used in this study (Portex^® I.D. 8mm, length 26cm) was quite high (5.0cmH₂O·1^–2·sec²), depending on the airflow, the presence of the endotracheal tube strongly affected the measurement of airway resistance during general anesthesia. K₁ measured by the above method, however, may be considered as the best way to evaluate the lower airway resistance independent of either lung volume or expiratory airflow.(Sakai T, Yoshida H, Yano H et al.: Measurement of airway resistance in anesthetized and paralyzed subjects: proposal for evaluation of K₁ values. J Anesth 2: 139–145, 1988)     

Radial artery-to-aorta pressure difference after discontinuation of cardiopulmonary bypass

To test whether the radial artery-to-aorta pressure gradient seen in some patients after cardiopulmonary bypass (CPB) is due to reduction in hand vascular resistance, the authors compared pressures in the ascending aorta with pressures in the radial artery before and after CPB in 12 patients. They increased hand vascular resistance by briefly occluding the radial and ulnar arteries at the wrist and recorded that effect on the radial artery-to-aorta pressure relationship. They also recorded the effect of wrist compression on radial artery pressures before and after CPB in 38 patients not having aortic pressure measurements. Before CPB in the first 12 patients, the radial systolic arterial pressure (SAP) was significantly higher (P less than 0.05) than the ascending aortic SAP, and wrist compression did not significantly affect that difference (P greater than 0.05). After CPB, the radial artery and aortic SAPs were not statistically different (P greater than 0.05), but wrist compression restored the higher radial artery SAP. The mean arterial pressure (MAP) was equal in four patients and 1-3 mmHg higher or lower in eight patients before CPB, and wrist compression did not alter those relationships. After CPB, MAP was equal in four patients; radial MAP was 1-3 mmHg higher or lower in six patients, and 7 and 10 mmHg lower in the last two patients.(ABSTRACT TRUNCATED AT 250 WORDS)     

Daily exercise lowers blood pressure and reduces visceral adipose tissue areas in overweight Japanese men

OBJECTIVE: To investigate the link between a reduction in blood pressure (BP) and daily exercise. DESIGN: Cross-sectional and longitudinal clinical intervention study with exercise education. SUBJECTS: 43 overweight Japanese men aged 32-59 years (BMI, 29.0+/-2.3 kg/m2) at baseline. Among the participants, a randomly selected 23 overweight men (BMI, 28.5+/-1.7) were further enrolled into the 10 months exercise program. MEASUREMENTS: BP was measured every week and steps per day were also recorded every day throughout the observation period. Fat distribution was evaluated by visceral fat (V) and subcutaneous fat (S) areas measured with computed tomography (CT) scanning at umbilical level, at before, 5 months and after intervention. Anthropometric parameters were also measured at same point. Aerobic exercise level, muscle strength, flexibility and calorie intake and insulin resistance (HOMA index) were investigated at before and after the study. RESULTS: In a cross sectional analysis, systolic BP (SBP) and diastolic BP (DBP) were significantly correlated with body composition. In a second longitudinal analysis, SBP was significantly reduced at 2 months and DBP was also reduced at 3 months, and almost maintained until the end of the observation period. Increasing daily walking was observed in 3 months and maintained until 10 months. Body composition, aerobic exercise level, muscle strength, flexibility and insulin resistance were significantly improved. There was positive correlation between DeltaDBP and Deltavisceral fat area (1-5, 5-10, 1-10 months). By stepwise multiple regression analysis, only Deltavisceral fat area was independently related to DeltaDBP at a significant level (1-10 months: DeltaDBP=-0.608+0.105Deltavisceral fat area, r2=0.227, P=0.0334). CONCLUSION: The present study indicated daily exercise lowers BP and visceral fat area is the critical factor for BP change.     

Effect of plaunotol on hypergastrinemia induced by long-term omeprazole administration in humans

Omeprazole markedly inhibits basal and stimulated gastric acid secretion and has the ability to produce hypergastrinemia and hyperplasia of enterochromaffin-like cells in humans. On the other hand, paunotol, an acyclic diterpene alcohol, has been reported to inhibit gastrin release by stimulating endogenous secretin release. We investigated the effect of plaunotol on serum gastrin levels after six to eight weeks of omeprazole (20 mg/day) administration in 22 patients (16 males, 6 females; mean age 52.3, range 36–70 years) with peptic ulcer disease. The patients were randomized to the following two groups: 11 subjects with omerprazole alone (single group) and 11 with omeprazole plus plaunotol (240 mg/day) (combination group) treatment. There were no significant differences between the two groups concerning age, sex, ulcer stage, ulcer history, environmental factors, andHelicobacter pylori (HP) prevalence. After complete drug(s) administration, serum immunoreactive (ir) -gastrin levels increased significantly in the single group (P<0.001) in contrast to the combination group, and plaunotol significantly inhibited hypergastrinemia induced by omeprazole administration (P<0.001). Significant increases in serum ir-calcitonin gene-related peptide concentrations were observed in the combination group compared to the single group (P<0.05). However, there were no significant changes in serum ir-secretin, somatostatin, and vasoactive intestinal polypeptide levels as well as ulcer healing and HP prevalence between the two groups. These findings suggest that plaunotol may suppress hypergastrinemia induced by long-term omeprazole administration, at least partly, via a certain brain-gut hormone affecting gastrin release.