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Charles D Fraser

Publications and source records attributed to Charles D Fraser.

At least 55 records · Page 3Linked to original sources
PubMed2004

Is bilateral monitoring of cerebral oxygen saturation necessary during neonatal aortic arch reconstruction?

UNLABELLED: In this study, we measured cerebral oxygenation in both cerebral hemispheres by using near-infrared spectroscopy before, during, and after regional low-flow cerebral perfusion (RLFP) to determine whether bilateral monitoring was necessary. Neonates undergoing aortic arch reconstruction with RLFP were studied. The bilateral regional cerebral oxygenation index was measured and recorded at 1-min intervals during the following periods: 1) before bypass, 2) during bypass before RLFP, 3) during RLFP, 4) on bypass after RLFP, and 5) post-bypass. Before bypass and on bypass before RLFP, the correlation (r = 0.979 and 0.852) and agreement (mean bias, right versus left, 0 and +2) between hemispheres were excellent. During RLFP, however, correlation (r = 0.35) and agreement (mean bias of the right versus left side, +6.3) worsened and only partially returned to baseline values after RLFP. Nine of 19 patients had sustained differences in cerebral oxygen saturation of >10%, always with the left side values less than the right. Bilateral monitoring detects desaturation in the left cerebral hemisphere during RLFP. The long-term consequences of lower saturations on the left side of the brain are unclear. IMPLICATIONS: Left-sided cerebral hemisphere oxygen saturation, measured with near-infrared spectroscopy, was less than right-sided cerebral oxygen saturation during regional low-flow cerebral perfusion used for neonatal aortic arch reconstruction.

Aorta, Thoracic↗
PubMed2004

Limiting circulatory arrest using regional low flow perfusion.

Deep hypothermic circulatory arrest (DHCA) is commonly used for neonatal cardiac surgery. However, prolonged exposure to DHCA is associated with neurologic morbidity. The Norwood operation and aortic arch advancement are procedures that typically require DHCA during surgical correction. Regional low flow perfusion (RLFP) can be used to limit or exclude the use of circulatory arrest. This technique involves cannulation of the innominate or subclavian artery using a Gore-Tex graft, allowing isolated cerebral perfusion. Data was collected in 34 patients undergoing either neonatal aortic arch reconstruction or the Norwood procedure using RLFP. All patients had two arterial pressure monitors using either the umbilical or femoral artery catheters and radial or brachial catheters. Adequacy of perfusion was determined using cerebral saturation, blood flow velocity, mean arterial pressures, and arterial blood gas results. Cerebral saturation and blood flow velocity were monitored using the near-infrared spectroscopy (NIRS) (INVOS 5100, Somanetics Corp, Troy, MI) and a transcranial Doppler pulse-wave ultrasound (TCD) (EME Companion, Nicolet Biomedical, Madison, WI), respectively throughout the entire bypass period. Blood gases were monitored using a point of care blood gas analyzer (Gem Premier, Mallinckrodt Sensor System, Inc., Ann Arbor, MI). Data collected revealed total bypass times for repair between 69-348 min, with a mean of 180 min. Regional low flow perfusion times lasted between 6-158 min, with an average of 50 min., and DHCA times ranged from 0-66 min, with a mean of 19 min. The perfusion techniques used allowed patient clinical data to remain consistent throughout the cardiopulmonary bypass period, regardless of lower flows (Figure 1) The 30-day postoperative mortality rate was 2.9 %, with no evidence of neurologic injury during follow up. In conclusion, regional low flow cerebral perfusion might benefit patients by limiting the use of circulatory arrest during cardiac surgery. Further study is necessary to evaluate patient outcomes, comparing regional cerebral perfusion and circulatory arrest techniques.

Anastomosis, Surgical↗
PubMed2004

Combined tricuspid valvuloplasty and superior cavopulmonary anastomosis for repair of traumatictricuspid valve injury.

Chronic tricuspid valve insufficiency secondary to blunt chest trauma is rare in the pediatric population, with fewer than 10 cases reported. Surgical repair has focused on the tricuspid valve. We present 2 cases of traumatic tricuspid valve insufficiency in pediatric patients after blunt chest trauma in whom tricuspid valve repair was performed along with superior cavopulmonary anastomosis. To our knowledge, this is the 1st report of the use of this combination of surgical procedures for repair of traumatic tricuspid regurgitation in either adults or children.

Adolescent↗
PubMed2003

Mediastinitis after pediatric cardiac surgery: a 15-year experience at a single institution.

BACKGROUND: The spectrum of sternal wound infections after cardiac surgery ranges from superficial infections to a deep sternal infection known as mediastinitis. Mediastinitis is a rare but clinically relevant source of postoperative morbidity and mortality in adult and pediatric patients after cardiac surgery. METHODS: We retrospectively identified all patients diagnosed with mediastinitis after cardiac surgery from January 1987 to December 2002 (17 patients/7,616 surgeries = 0.2%). Demographic data, cardiac diagnosis, cardiac surgery, hospital length of stay, associated medical diagnosis, and surgical treatment for mediastinitis were collected. RESULTS: Fifteen pediatric patients (age < 18 years) were diagnosed with mediastinitis (mean age at diagnosis 37.5 months, range 21 days to 17 years. The median postoperative day of diagnosis was 14 days (6 to 50 days). The most common organism was Staphylococcus species (n = 9). Six patients had an associated bacteremia. The median hospital length of stay for all patients was 42.5 days (range 16 to 163 days). The hospital mortality was 1 of 15 (6%). Each patient was treated with intravenous antibiotics; sternal debridement; and rectus abdominus flap reconstruction (n = 7), pectoralis muscle flap reconstruction (n = 3), omentum reconstruction (n = 1), or primary sternal closure (n = 4). Three patients have undergone redo-sternotomy with orthotopic heart transplantation, bidirectional cavopulmonary anastomosis, and replacement of a right ventricle to pulmonary artery homograft. CONCLUSIONS: Timely diagnosis, aggressive sternal debridement, and liberal use of rotational muscle flaps can potentially minimize the morbidity and mortality in pediatric postoperative cardiac patients. Subsequent redo-sternotomy has not been problematic.

Adolescent↗
PubMed2003

Regional low-flow perfusion provides comparable blood flow and oxygenation to both cerebral hemispheres during neonatal aortic arch reconstruction.

OBJECTIVE: The aim of this study was to measure cerebral oxygenation, cerebral blood volume index, and cerebral blood flow velocity values in both cerebral hemispheres before, during, and after regional low-flow cerebral perfusion for neonatal aortic arch reconstruction and to test the hypothesis that cerebral blood volume index measured by near infrared spectroscopy correlates with cerebral blood flow velocity measured by transcranial Doppler ultrasonography. METHODS: Bilateral near infrared spectroscopy and transcranial Doppler ultrasonography sensors were placed, and values were recorded immediately before, during, and after regional low-flow cerebral perfusion at 18 degrees C. Cerebral oxygen saturations, cerebral blood flow velocities, and cerebral blood volume index values were compared by Mann-Whitney U test. Correlations between values of cerebral blood volume index and cerebral blood flow velocity were tested with Spearman rank order correlation. RESULTS: Twenty patients were studied. Median cerebral oxygen saturations for the right and left sides were 95% and 95% before regional low-flow cerebral perfusion, 95% and 87% during regional low-flow cerebral perfusion (P =.054), and 93% and 94% after regional low-flow cerebral perfusion. Median cerebral blood flow velocity values did not change during regional low-flow cerebral perfusion. Cerebral blood volume index exhibited a poor correlation with cerebral blood flow velocity. CONCLUSIONS: Regional low-flow cerebral perfusion provides comparable blood flows and oxygenation to both cerebral hemispheres. Transcranial Doppler ultrasonography is recommended as a corroborative method with near-infrared spectroscopy to guide flow during regional low-flow cerebral perfusion, because cerebral blood volume index does not correlate with cerebral blood flow velocity.

Aorta, Thoracic↗
PubMed2003

Use of near-infrared spectroscopy to monitor regional cerebral oxygen saturation during infrarenal aortic crossclamping in piglets.

PURPOSE: The hemodynamic changes induced by infrarenal aortic crossclamping have been well documented, but the effects of such crossclamping on cerebral perfusion are unknown. To investigate these effects, we used near-infrared spectroscopy (NIRS) to monitor regional cerebral oxygen saturation (rSO2) during infrarenal aortic crossclamping in a piglet model. METHODS: The study involved 19 piglets, each weighing 7.8 +/- 1 kg. The NIRS sensor was placed on each animal's forehead. General anesthesia was induced, and the infrarenal abdominal aorta was mobilized through a laparotomy. After heparin (1 mg/kg) was administered, crossclamps were applied proximally and distally. A 2 mm segment was resected from the proximal aortic stump, and an aorto-aortic anastomosis was performed. RESULTS: Crossclamping lasted for 30.6 +/- 6.7 min. Between the time of baseline measurement and clamp application, the rSO2 did not decrease significantly (65.4%+/- 8.9% vs. 62.4%+/- 7.8%). However, significant decreases in the rSO2 occurred between baseline measurement and clamp removal (65.4%+/- 8.9% vs. 55.7%+/- 8.9%; P<0.01), between baseline measurement and the end of surgery (65.4%+/- 8.9% vs. 57.7%+/- 7.5%; P<0.01), and between clamp application and removal (62.4%+/- 7.8% vs. 55.7%+/- 8.9%; P<0.01). At these same intervals, no intergroup differences occurred in the temperature, heart rate, or mean arterial pressure. CONCLUSION: Infrarenal aortic crossclamping significantly decreases the rSO2. NIRS, which has the advantages of being non-invasive and continuous, may be useful for monitoring this variable intraoperatively.

Analysis of Variance↗
PubMed2003

Novel cerebral physiologic monitoring to guide low-flow cerebral perfusion during neonatal aortic arch reconstruction.

OBJECTIVE: This study was undertaken to describe the combined measurement of cerebral blood flow velocity and cerebral oxygen saturation as a guide to bypass flow rate for regional low-flow perfusion during neonatal aortic arch reconstruction. METHODS: Data were prospectively collected from 34 patients undergoing neonatal aortic arch reconstruction with regional low-flow perfusion. Cerebral oxygen saturation and blood flow velocity were measured by near-infrared spectroscopy and transcranial Doppler ultrasonography, respectively, throughout cardiopulmonary bypass. After cooling to 17 degrees C to 22 degrees C, baseline values of cerebral oxygen saturation and blood flow velocity were recorded during full-flow bypass. Regional low-flow perfusion was instituted for aortic arch reconstruction, and bypass flow rate was adjusted to maintain cerebral oxygen saturations and blood flow velocities within 10% of baseline recorded during cold full-flow bypass. Cerebral oxygen saturations and blood flow velocities were recorded again after repair during full-flow hypothermic bypass. Bypass flow during regional low-flow perfusion was recorded, as were arterial pressure and blood gas data. One-way repeated measures analysis of variance was used to determine differences in values during regional low-flow perfusion relative to baseline and after perfusion. RESULTS: A mean bypass flow of 63 mL/(kg x min) was required to maintain cerebral oxygen saturations and blood flow velocities within 10% of baseline. Mean arterial pressure had a poor correlation with the required bypass flow rate (r(2) = 0.006 by linear regression analysis). Fourteen of 34 patients had a cerebral oxygen saturation of 95% during regional low-flow perfusion, placing them at risk for cerebral hyperperfusion if the cerebral oxygen saturation had been used alone to guide bypass flow. Pressure was detected in the umbilical or femoral artery catheter (mean 12 mm Hg) in all patients during regional low-flow perfusion. CONCLUSIONS: Cerebral blood flow velocity, as determined by transcranial Doppler ultrasonography, adds valuable information to cerebral oxygen saturation data in guiding bypass flow during regional low-flow perfusion. Its most important use may be prevention of cerebral hyperperfusion during periods with high near-infrared spectroscopic saturation values.

Analysis of Variance↗
PubMed2002

Aortic arch advancement: the optimal one-stage approach for surgical management of neonatal coarctation with arch hypoplasia.

BACKGROUND: The optimal surgical treatment for neonatal coarctation with aortic arch hypoplasia (NCoAo/AAH) is controversial. Important long-term concerns include arch growth. We report our results obtained with a one-stage radical approach of coarctectomy and aortic arch advancement for NCoAo/AAH. METHODS: From June 1995 to December 2000, 65 newborns with NcoAo/AAH underwent coarctectomy and aortic arch advancement via a median sternotomy under deep hypothermic circulatory arrest. Patients were classified by diagnosis: group 1, isolated NCoAo/AAH (n = 13); group 2, NCoAo/AAH with ventricular septal defect (n = 20); and group 3, NCoAo/AAH with complex cardiac lesions (n = 32). RESULTS: The study population included 36 boys and 29 girls. Mean age was 13 +/- 1.7 days (range 1 to 43 days). Mild to moderate left ventricular outflow tract obstruction was present in 15 patients. Mean body weight was 3.4 +/- 0.1 kg (range 1.6 to 5 kg). Eight babies were premature. The mean Z value for the aortic arch was -4 +/- 0.3 (range -2 to -4.5) and for the isthmus -4.5 +/- 0.2 (range -3 to -7). Mean deep hypothermic circulatory arrest time was 28 +/- 2 minutes (range 14 to 60 minutes). Mean intensive care unit stay was 6 +/- 1 days (range 2 to 30 days). There were three early deaths (all in groups 2 and 3) and two late deaths (in group 3) (5-year actuarial survival, 91% +/- 7.9%). There was one recurrence (5-year actuarial freedom from recurrence, 98% +/- 4%). Peak Doppler velocity across the arch in the remaining patients was 1 +/- 0.1 m/s (range 0 to 2.2 m/s). CONCLUSIONS: Coarctectomy and aortic arch advancement is the optimal surgical method for management of NCoAo/AAH. It has low operative morbidity and mortality and a very low incidence of recoarctation or arch obstruction.

Aorta, Thoracic↗
PubMed2002

BioGlue surgical adhesive impairs aortic growth and causes anastomotic strictures.

BACKGROUND: BioGlue surgical adhesive (CryoLife, Inc, Kennesaw, GA) is currently being used to secure hemostasis at cardiovascular anastomoses in adults. Interference with vessel growth would preclude its use during congenital heart surgery. The purpose of this study was to determine if BioGlue reinforcement of aortic anastomoses impairs vessel growth and causes strictures. METHODS: Ten 4-week-old piglets (8.0 +/- 1.4 kg) underwent primary aorto-aortic anastomoses. Five piglets were randomly assigned to anastomotic reinforcement with BioGlue. After a 7-week growth period, the aortas were excised for morphometric analysis and histopathology. RESULTS: Weight gains were similar in both groups. In BioGlue animals, however, aortic circumference increased only 1.5 +/- 0.8 mm (versus 2.7 +/- 0.8 mm in controls; p = 0.054). BioGlue animals developed a 33.9% stenosis of the aortic lumen area (versus 3.7% in controls, p = 0.038). Adventitial changes reflecting tissue injury and fibrosis were present in all BioGlue animals versus none of the control animals (p = 0.008). CONCLUSIONS: BioGlue reinforcement impairs vascular growth and causes stricture when applied circumferentially around an aorto-aortic anastomosis. This adhesive should not be used on cardiovascular anastomoses in pediatric patients.

Age Factors↗
PubMed2002

Novel anti-factor D monoclonal antibody inhibits complement and leukocyte activation in a baboon model of cardiopulmonary bypass.

BACKGROUND: Adverse outcomes after cardiopulmonary bypass (CPB) are often related to systemic inflammation triggered by complement and leukocyte activation. To determine how inhibition of the alternative complement pathway affects systemic inflammation and tissue injury, we studied a novel monoclonal antibody (Mab), anti-human factor D murine Mab 166-32, in baboons. METHODS: Fourteen baboons (mean weight, 15 kg) underwent hypothermic CPB. The treatment group (n = 7) received a single injection of anti-factor D Mab 166-32 (5 mg/kg), and the control group (n = 7) was given saline solution. After initiation of CPB, all animals were subjected to 20 minutes of core cooling (rectal temperature, 27 degrees C), followed by 60 minutes of aortic cross-clamping, 25 minutes of rewarming, and 30 minutes of normothermic CPB. Blood samples were collected before CPB, during CPB, and 1, 2, 3, 6, and 18 hours after CPB. To measure neutrophil and monocyte activation, we performed flow cytometry for CD11b expression, ELISA for complement activation (Bb, C3a, C4d, and sC5b-9) and interleukin-6 (IL-6) production, and tissue injury studies for creatine kinase MB isoenzymes (CK-MB), creatine kinase (CK), and lactic dehydrogenase (LDH) levels. RESULTS: Anti-factor D Mab almost completely inhibited plasma Bb, C3a, and sC5b-9 production during CPB (P < .001). CD11b expression on neutrophils (129 +/- 5% vs. 210 +/- 42%; P = .0006) and on monocytes (139 +/- 14% vs. 245 +/- 43%; P = .0002) was also lower in the treatment group during CPB. The treated animals had a significantly smaller increase in plasma IL-6 concentrations than did the control animals (71 +/- 27 pg/mL vs. 104 +/- 54 pg/mL; P = .0002). CK-MB levels were also lower in the treatment group 6 hours after the end of CPB (204 +/- 30 vs. 335 +/- 59 IU/L; P = .003) and 18 hours after the end of CPB (P < .05). Creatine kinase levels (6 and 18 hours after the end of CPB) and LDH levels (3 and 6 hours after the end of CPB) showed patterns similar to those of CK-MB (P < .05). CONCLUSIONS: The alternative complement pathway plays a major role in systemic inflammation during CPB. Inhibition of complement activation via the alternative pathway by anti-factor D Mab 166-32 significantly reduces leukocyte activation and tissue injury in our baboon model.

Animals↗
PubMed2002

Anomalous origin of left coronary artery from the right pulmonary artery in association with type III aortopulmonary window and interrupted aortic arch.

Anomalous origin of the left coronary artery from the pulmonary artery, also known as Garland-Bland-White syndrome, usually occurs as an isolated condition. We report an infant with caudal regression sequence diagnosed with interrupted aortic arch type B and type III aortopulmonary window, who was found to have anomalous origin of the left coronary artery from the right pulmonary artery at surgical repair. Successful repair of the aortopulmonary window and interruption was performed with reimplantation of the left coronary artery into the ascending aorta. This report highlights the importance of closely assessing the coronary ostia in patients undergoing complex aortopulmonary window repair.

Anastomosis, Surgical↗
PubMed2002

Preoperative identification of coronary arterial anatomy in complete transposition, and outcome after the arterial switch operation.

BACKGROUND: Perceived correlation between the coronary arterial anatomy in patients with complete transposition, and the outcome of the arterial switch procedure, has made preoperative identification of their patterns standard practice. PURPOSE: Our purpose was to assess the accuracy of preoperative echocardiographic identification of coronary arterial patterns, to evaluate the necessity of preoperative imaging by angiography, and to determine the impact of the coronary arterial anatomy on outcome. METHODS: We reviewed the medical records of all patients referred for an arterial switch operation between August 1995 and January 2000. The anatomy as described at the time of the operation using the Leiden convention was compared to the preoperative echocardiographic and angiographic findings. RESULTS: The procedure had been performed in 67 patients, at a mean age of 9 days, with a range from 3 days to 15 months. In 42 patients, the ventricular septum was intact, while 21 patients had a ventricular septal defect, and the other four had double outlet right ventricle with the aorta anterior and rightward. In 52 patients, the left coronary artery arose from sinus #1, and the right from sinus #2. In 8 patients, the interventricular branch of the left coronary artery arose from sinus #1, with the circumflex coronary artery arising together with the right coronary artery from sinus #2. In three patients, all three coronary arteries arose from sinus #1, while in the remaining individual patients, a large conal branch arose with the left coronary artery from sinus #1, the right coronary and left anterior descending arteries arose from sinus #1, all three coronary arteries took origin from sinus #2, and the left anterior descending and right coronary artery arose from sinus #1 with no circumflex coronary artery identifiable, respectively. In two patients (4%), we identified an intramural coronary arterial course. Echocardiography and angiography were comparable (81% versus 86%) in delineating the coronary arterial anatomy. Patients with a single arterial orifice, or an atypical coronary arterial anatomy, had a slightly longer stay on the intensive care unit, and in the hospital, but showed no difference in mortality. In fact, there was no early mortality (70% confidence limits; 0-2.9%), while two patients died late (2.9%). CONCLUSION: We conclude that complex coronary arterial anatomy does not preclude a successful arterial switch procedure, although patients with a single coronary artery, or other arterial patterns, had a slightly longer hospital course. Preoperative echocardiographic evaluation is comparable to nonselective coronary angiography. Irrespective of complexity, nonetheless, the coronary arteries can successfully be translocated, obviating the need for preoperative coronary angiography.

Cardiac Surgical Procedures↗
PubMed2002

Pediatric physiologic pulsatile pump enhances cerebral and renal blood flow during and after cardiopulmonary bypass.

Controversy over benefits of pulsatile flow after pediatric cardiopulmonary bypass (CPB) continues. Our study objectives were to first, quantify pressure and flow waveforms in terms of hemodynamic energy, using the energy equivalent (EEP) formula, for direct comparisons, and second, investigate effects of pulsatile versus nonpulsatile flow on cerebral and renal blood flow, and cerebral vascular resistance during and after CPB with deep hypothermic circulatory arrest (DHCA) in a neonatal piglet model. Fourteen piglets underwent perfusion with either an hydraulically driven dual-chamber physiologic pulsatile pump (P, n = 7) or a conventional nonpulsatile roller pump (NP, n = 7). The radiolabeled microsphere technique was used to determine the cerebral and renal blood flow. P produced higher hemodynamic energy (from mean arterial pressure to EEP) compared to NP during normothermic CPB (13 +/- 3% versus 1 +/- 1%, p < 0.0001), hypothermic CPB (15 +/- 4% versus 1 +/- 1%, p < 0.0001) and after rewarming (16 +/- 5% versus 1 +/- 1%, p < 0.0001). Global cerebral blood flow was higher for P compared to NP during CPB (104 +/- 12 ml/100g/min versus 70 +/- 8 ml/100g/min, p < 0.05). In the right and left hemispheres, cerebellum, basal ganglia, and brainstem, blood flow resembled the global cerebral blood flow. Cerebral vascular resistance was lower (p < 0.007) and renal blood flow was improved fourfold (p < 0.05) for P versus NP, after CPB. Pulsatile flow generates higher hemodynamic energy, enhancing cerebral and renal blood flow during and after CPB with DHCA in this model.

Age Factors↗