Heart Surgery Procedures Research Articles

The Past 50 Years of Cardiovascular Surgery

The Past 50 Years of Cardiovascular Surgery

Minimally invasive pediatric cardiac surgery.

Minimally invasive cardiac surgery has evolved in response to the intrinsic irony facing cardiac surgeons: that we must injure our patients to treat them. In recent years, advances in fiberoptic imaging technology, applied to other surgical specialties, suggested the possibility that cardiac surgery might also be performed endoscopically. The anatomic and spatial constraints of pediatric cardiac surgery, and its dependence on extreme levels of speed, precision, and three-dimensional perception, made the application of remote, two-dimensional operating systems seem impossible, or at least imprudent in this special group of patients. Despite these limitations, however, applications of video-assisted endoscopic surgical techniques have been demonstrated to allow the safe and effective performance of an expanding range of operative procedures in congenital heart surgery. The guided development of new technology will accelerate this process in the coming years.

Cerebral Blood Flow and Oxygen Metabolism during Cardiopulmonary Bypass with Moderate Hypothermic Selective Cerebral Perfusion

Cerebral blood flow was measured using transcranial doppler during cardiopulmonary bypass in nine patients with selective cerebral perfusion for surgery of arch aorta (group S). For comparison, 11 adult open heart patients (group C) were also measured. The authors' selective cerebral perfusion at 28°C resulted in moderate hypothermia and antegrade perfusion using independent pumps for three branches. Total flow in the three branches was 500 ml/min. A Labodop DP-100 doppler ultrasound velocimeter was used to measure middle cerebral arterial blood flow velocity. Hemoglobin concentration and oxygen saturation were also measured in arterial and jugular venous blood. The arteriovenous oxygen content difference (Ca-vO2) was calculated and multiplied by the middle cerebral arterial blood flow velocity value, which resulted in the cerebral metabolic rate for oxygen (CMRO2). The cerebral perfusion pressure of group S was lower than in group C, and the arterial carbon-dioxide tension (PaCO2) of group S was higher than in group C during cardiopulmonary bypass. Middle cerebral arterial blood flow velocity values of both groups remained constant before, during and after cardiopulmonary bypass. The CMRO2 decreased during cardiopulmonary bypass and showed no difference between the two groups. The changes in PaCO2 might be significant factors in the increase in cerebral blood flow during selective cerebral perfusion. This study supports the conclusion that, compared with our routine open heart surgery procedures, our selective cerebral perfusion procedures had the same cerebral blood flow and oxygen metabolism during cardiopulmonary bypass.

Cerebral blood flow and oxygen metabolism during cardiopulmonary bypass with moderate hypothermic selective cerebral perfusion

Cerebral blood flow was measured using transcranial doppler during cardiopulmonary bypass in nine patients with selective cerebral perfusion for surgery of arch aorta (group S). For comparison, 11 adult open heart patients (group C) were also measured. The authors' selective cerebral perfusion at 28°C resulted in moderate hypothermia and antegrade perfusion using independent pumps for three branches. Total flow in the three branches was 500 ml/min. A Labodop DP-100 doppler ultrasound velocimeter was used to measure middle cerebral arterial blood flow velocity. Hemoglobin concentration and oxygen saturation were also measured in arterial and jugular venous blood. The arteriovenous oxygen content difference (Ca-vO 2) was calculated and multiplied by the middle cerebral arterial blood flow velocity value, which resulted in the cerebral metabolic rate for oxygen (CMRO 2). The cerebral perfusion pressure of group S was lower than in group C, and the arterial carbon-dioxide tension (PaCO 2) of group S was higher than in group C during cardiopulmonary bypass. Middle cerebral arterial blood flow velocity values of both groups remained constant before, during and after cardiopulmonary bypass. The CMRO 2 decreased during cardiopulmonary bypass and showed no difference between the two groups. The changes in PaCO 2 might be significant factors in the increase in cerebral blood flow during selective cerebral perfusion. This study supports the conclusion that, compared with our routine open heart surgery procedures, our selective cerebral perfusion procedures had the same cerebral blood flow and oxygen metabolism during cardiopulmonary bypass.

Minimally invasive pediatric cardiac surgery.

Minimally invasive cardiac surgery has evolved in response to the intrinsic irony facing cardiac surgeons: that we must injure our patients to treat them. In recent years, advances in fiberoptic imaging technology, applied to other surgical specialties, suggested the possibility that cardiac surgery might also be performed endoscopically. The anatomic and spatial constraints of pediatric cardiac surgery, and its dependence on extreme levels of speed, precision, and three-dimensional perception, made the application of remote, two-dimensional operating systems seem impossible, or at least imprudent in this special group of patients. Despite these limitations, however, applications of video-assisted endoscopic surgical techniques have been demonstrated to allow the safe and effective performance of an expanding range of operative procedures in congenital heart surgery. The guided development of new technology will accelerate this process in the coming years.

Occupational exposure to desflurane and isoflurane during cardiopulmonary bypass: is the gas outlet of the membrane oxygenator an operating theatre pollution hazard?

We have compared occupational exposure to isoflurane and desflurane during cardiopulmonary bypass, with and without a scavenging system at the membrane oxygenator outlet. Trace concentrations of volatile anaesthetics were measured by a direct reading instrument in 40 elective heart surgery procedures. Measurements were obtained in the breathing zones of the anaesthetist and perfusionist. When a scavenging system was used, median desflurane values were less than 0.3 ppm and isoflurane values less than 0.2 ppm. Without a scavenging system values were, in general, three- (isoflurane) to five- (desflurane) fold higher. We conclude that the use of a scavenging system at the membrane oxygenator outlet can reduce occupational exposure to volatile anaesthetics. We therefore recommend routine use of scavenging devices during cardiopulmonary bypass.

P-43 Cardiac arrest after open heart surgery and interventional procedures

P-43 Cardiac arrest after open heart surgery and interventional procedures

A CASE OF CHOLELITHIASIS AFTER DOUBLE VALVE REPLACEMENT

We encountered a case of cholelithiasis which was recognized 4 years after double valve replacement with Bjork-Shiley valves. The cause of the cholelithiasis was thought to be relatively mild hemolysis. The patient was a 53-year-old female, with a previous history of mitral and aortic replacements with Bjork-Shiley valves for aortic stenosis, mitral stenoinsufficiency and tricuspid regurgitaiton 5 years previously. Cholecystectomy was performed for cholelithiasis in August 1985. Gallstones were black and had a large amount of metal elements, particularly copper and iron.Valve replacement is one of the most common procedures in heart surgery. However, hemolysis after valve replacement is an inevitable complication. Therefore, after valve replacement, patients should be observed carefully for cholelithiasis by echography.

Postoperative (pressure) alopecia

Postoperative localized alopecia has been reported most commonly after certain gynecologic and open heart surgery procedures, the likelihood of hair loss and the chance of permanence correlating with the length of the anesthesia and the intubation. Some cases of pressure-induced alopecia have been described after prolonged coma from other causes. Coma blisters have been reported after drug overdoses, but clinically similar blisters (not tested by biopsy) have been seen in other cases of coma. We present three cases of postoperative (pressure) alopecia and propose that both coma blisters and postoperative alopecia arise from the same phenomenon--probably pressure-induced ischemia.

Current Status of Palliative vs. Corrective Procedures in Congenital Heart Surgery

Current Status of Palliative vs. Corrective Procedures in Congenital Heart Surgery

Current Status of Palliative vs. Corrective Procedures in Congenital Heart Surgery

In open-pit mines, the traditional truck-based haulage system has consumed large amounts of energy in the haulage sector for many years. The use of continuous in-pit crushing and conveying (IPCC) systems is a viable option to significantly reduce energy consumption in this sector. Considering the relationship between the energy data and the amount of mineral extracted in the haulage sector of an open-pit titanium mine and the production of open-pit iron, copper and coal mines between 2013 and 2017 and 2028, this paper estimated the energy consumption in the haulage sector using a continuous system and a traditional system and also the potential for energy savings in case of using an IPCC system instead of the truck-based system in the mines. It was estimated that a continuous system consumes, on average, 303.94 GJ and a traditional system consumes, on average, 471.48 GJ to transport the minerals under study. In addition, it was estimated that in 2028, the use of IPCC system instead of the truck-based system in the haulage sector to transport 3482, 28.7 and 9746.4 million tons of iron, copper and coal minerals will save energy consumption in this sector by 28.26, 0.23 and 79.90 MMBTU, respectively. Finally, the use of IPCC systems instead of the traditional system was economically examined and the superiority of continuous systems over traditional systems was demonstrated from the two perspectives, operating costs and energy costs.