PubMed · 4783028
The source did not provide an abstract. Follow the original record for more information.
Explore connections, maps & timelines
H H Bendixen. 1973. Pacemaker-induced hypotension.. https://doi.org/10.1001/archsurg.1973.01350210001001
Cite the original work for its findings. Save a collection to share your selection of sources.
KEEP EXPLORING
Sensitive methods are required to record electrical evoked potentials over the visual cortex to evaluate the efficacy and safety of a retinal prosthesis before it can be implanted on the retinal surface of patients afflicted by outer retinal diseases. This study was designed to examine subdural electrodes as a mean to evaluate cortical evoked potentials in response to light and electrical stimulation of the retina in three dogs under two methods of anesthesia-halothane and propofol. Results showed that subdural electrodes could be stabilized over the visual cortex for several (3-5) months, and that they were 6.95 times more sensitive than subdermal electrodes in recording cortical visual evoked potentials (VEPs) and 4.31 times more sensitive in recording cortical electrical evoked potentials under both methods of anesthesia. The waveforms' shape changed for each electrode in the subdural array during 6/6 (100%) and 20/38 (52%) multi-channel recording sessions under halothane and propofol, respectively. This change could point to a cortical retinotopic organization versus hierarchical organization of different cortical areas for a given retinal stimulus. In summary, subdural electrodes show promising results for recording visual and electrical evoked responses (EERs) and thus for evaluation of the retinal prosthesis.
INTRODUCTION: During the past three decades laparoscopy has significantly improved. As fundoplication extensively benefits by the great advantages of the minimally invasive approach, many surgeons chose laparoscopic fundoplication for the treatment of gastroesophageal reflux in adults and children as well. Pneumothorax, cardiovascular collapse, hypoxia, and hypercarbia are some of the anesthesiologist's principal fears during carbon dioxide insufflation. Thus, monitoring cardiovascular and respiratory status is mandatory to early detect any complication and to maintain a proper balance during pneumoperitoneum. MATERIALS AND METHODS: At Gaslini Children's Hospital we performed a prospective nonrandomized study aimed at describing the main cardiorespiratory changes produced by pneumoperitoneum in 33 pediatric patients operated on by laparoscopic fundoplication between January 2000 and June 2001. Patients were divided into two groups; namely, group A and group B. Group A included 14 patients with chronic respiratory symptoms, and group B included 19 children who preoperatively mainly emphasized gastrointestinal symptoms. We monitored intraoperative cardiorespiratory status, timed length of surgery, and described intraoperative complications. RESULTS: No significant cardiovascular changes occurred during carbon dioxide insufflation. Partial oxygen saturation remained still in all the patients. End tidal CO2, meanly higher in group A children, increased in all the patients after pneumoperitoneum creation, but never exceeded 45 mmHg. Similarly, peak inspiratory pressure increased in all the patients, but was always maintained within acceptable values. Finally, group B patients required a harder and slower surgery, whose length seems to be negatively influenced by age. No intraoperative complication occurred. CONCLUSIONS: Carbon dioxide insufflation does not impair cardiovascular function, if intraabdominal pressure is maintained lower than 10 mmHg nor does it interfere with gas exchanges. Pneumoperitoneum slightly reduces ventilatory function, mainly in respiratory patients with various degrees of underlying bronchopulmonary impairments, but this effect is easily correctable. Thus, laparoscopic fundoplication is feasible and safe in both respiratory and gastroenterological patients, although surgery is easier and faster if periesophagitis is less evident.