Biomedical subjects

Patricia Byers

Publications and source records attributed to Patricia Byers.

9 recordsLinked to original sources

PubMed2005

Effects of weight loss after gastric bypass on right and left ventricular function assessed by tissue Doppler imaging.

To evaluate the effects of substantial weight loss on tissue Doppler imaging parameters of right ventricular (RV) and left ventricular (LV) systolic and diastolic function, we performed standard echocardiography and tissue Doppler imaging in 17 patients with severe obesity before and after gastric bypass. Patients lost 39 +/- 10 kg over 7.6 +/- 3.6 months. Adjusted LV mass decreased (134 +/- 41 to 119 +/- 31 kg/m, p = 0.031). After weight loss, the ratios of early-to-late diastolic mitral and tricuspid inflow velocities increased (1.3 +/- 0.2 to 1.6 +/- 0.5, p = 0.02; 1.0 +/- 0.1 to 1.6 +/- 0.3, p = 0.003). Early diastolic tissue Doppler velocities increased at both the lateral and septal mitral annulus (7.6 +/- 1.5 to 9.3 +/- 2.5 cm/s, p = 0.009; and 6.6 +/- 1.4 to 7.7 +/- 1.7 cm/s; p = 0.028, respectively) and for their 2-site average (7.2 +/- 1.0 to 8.5 +/- 1.7 cm/s, p = 0.007). Early diastolic tricuspid annular velocity increased (7.2 +/- 2.8 to 10.6 +/- 2.3 cm/s, p <0.001) as did the ratio of early-to-late tricuspid annular diastolic velocity (0.9 +/- 0.4 to 1.1 +/- 0.2, p = 0.038). Tricuspid annular systolic velocity increased (8.6 +/- 2.5 to 10.3 +/- 2.7 cm/s, p = 0.037). In patients with severe obesity, significant weight loss results in an increase in tricuspid annular systolic and early diastolic velocities and mitral annular early diastolic velocities.

Adult↗

PubMed2004

Tissue Doppler imaging of the right and left ventricle in severe obesity (body mass index >35 kg/m2).

We investigated right and left heart function in 51 patients with a body mass index of >35 kg/m(2) who underwent evaluation for gastric bypass surgery using standard Doppler echocardiography and color tissue Doppler imaging. Left atrial diameter (3.7 +/- 0.5 vs 3.3 +/- 0.4 cm, p <0.001), left ventricular end-diastolic diameter (5.0 +/- 0.6 vs 4.5 +/- 0.4 cm, p <0.001), and left ventricular mass index (119 +/- 49 vs 76 +/- 26 g/m, p <0.001) were increased in patients with severe obesity. Early diastolic mitral annular velocity (7.5 +/- 2.1 vs 9.6 +/- 3.0 cm/s, p <0.001), early diastolic/late diastolic mitral annular velocity ratio (1.38 +/- 0.6 vs 1.94 +/- 1.3, p = 0.007), early diastolic tricuspid annular velocity (7.8 +/- 2.6 vs 9.5 +/- 2.4 cm/s, p = 0.002), early diastolic/late diastolic tricuspid annular velocity ratio (0.9 +/- 0.36 vs 1.1 +/- 0.4, p = 0.048), and mitral annular systolic velocity (5.7 +/- 1.3 vs 6.5 +/- 1.5 cm/s, p = 0.012) were significantly lower in obese patients. Early diastolic mitral inflow/mitral annular velocity ratio was increased in the obese (13.5 +/- 4.7 vs 9.1 +/- 3.6, p <0.001). Tricuspid annular systolic velocities did not differ.

Adolescent↗

PubMed2004

Intestinal and multivisceral transplantation after abdominal trauma.

SUMMARY: BACKGROUND Some trauma victims who survive acute illness develop lingering, debilitating syndromes that are incompatible with any semblance of normalcy. Intestinal failure, in particular, exacts a high price in terms of quality of life. Total parenteral nutrition (TPN) has served these patients well, but complications limit its long-term therapeutic effect. Consequently, transplantation is emerging as a life-saving therapy for some patients with the short gut syndrome. METHODS We reviewed eight adult and two pediatric recipients of intestinal and multivisceral transplants after severe abdominal trauma. Background demographics, type of abdominal trauma, transplant procedure, postoperative complications, and survival rates were appraised. This group was also compared with 47 nontrauma recipients of intestinal transplants performed during the same period. RESULTS Four patients (40%) died postoperatively (postoperative days 7, 53, 87, and 91) as a result of multiple organ failure after graft pancreatitis (n = 1), viral encephalitis (n = 1), and sepsis after severe rejection (n = 2). Six patients (60%) are alive (postoperative days 52-1,783). All are off TPN. The 4-year patient survival was 58%, with no significant difference between trauma and nontrauma patients.CONCLUSION Intestinal and multivisceral transplantation are viable options for the treatment of irreversible intestinal failure associated with severe trauma. Surviving patients are TPN independent and have a satisfactory quality of life.

Abdominal Injuries↗

PubMed2003

Developing a comprehensive diagnostic and interventional nephrology program at an academic center.

Procedure-related delays in the treatment of patients with renal disease can be minimized and nephrology care can be delivered more efficiently by a nephrologist trained in nephrology-related procedures. Referrals to a radiologist for renal ultrasound and biopsy, to a surgeon for dialysis access placement, and to an interventional radiologist for dialysis catheter placement and vascular access procedures are time consuming and inconvenient to patients with renal disease. Moreover, such an approach may result in delays in the availability of critical diagnostic information and a break in the continuity of care. In an effort to optimize the care of nephrology patients, we developed a diagnostic and interventional nephrology (DIN) program that effectively deals with nephrology-related procedures in a timely manner. At present, some of the commonly performed nephrology-related procedures at our center include diagnostic ultrasonography, ultrasound-guided renal biopsy, peritoneal dialysis access procedures, permanent tunneled hemodialysis catheter placement, and endovascular procedures for arteriovenous dialysis access dysfunction. To date, we have performed 893 procedures during a period of 2 years. This article describes our approach and the tools required to develop a DIN program at an academic medical center.

Academic Medical Centers↗

PubMed2003

Peritoneoscopic placement of peritoneal dialysis catheter and bowel perforation: experience of an interventional nephrology program.

BACKGROUND: Bowel perforation is an uncommon but serious complication of peritoneoscopic peritoneal dialysis (PD) catheter insertion. The approach to diagnosis of bowel perforation utilizing this technique has not been previously published. The authors report their experience with the diagnosis and management of bowel perforation in the context of peritoneoscopic placement of PD catheters. METHODS: The authors retrospectively reviewed the records of 750 PD catheters inserted over a 12-year period (January 1991 to May 2003) utilizing peritoneoscopic technique. RESULTS: Six (0.8%) patients experienced bowel perforation during the procedure. The diagnosis was made immediately during the procedure in 5 (83%) of the 6 patients. Of these 5, peritoneoscopy confirmed intrabowel position of the cannula by visualizing bowel mucosa (n = 3) and hard stool (n = 1). The fifth patient showed extrusion of fecal matter upon trocar withdrawal before peritoneoscopy. All 5 had emanation of foul-smelling gas through the cannula. Bowel rest and broad-spectrum intravenous antibiotics were initiated. Of the 5, 1 required surgery, whereas the others were discharged home after 3 days. The sixth patient had fever, severe peritoneal irritation, and polymicrobial peritonitis the morning after the procedure. In this patient, no evidence of bowel injury was noted during the procedure except for brief emanation of foul-smelling gas. He required surgical intervention. CONCLUSION: Bowel perforation can be diagnosed immediately in most patients undergoing peritoneoscopic PD catheter insertion. A majority of these patients can be treated medically. The surgical team should be consulted if the patient shows clinical deterioration or has signs of peritoneal irritation.

Abdomen, Acute↗

PubMedDate not supplied

Outcomes of bariatric surgery in patients > or =65 years.

BACKGROUND: Although the Medicare Coverage Advisory Committee found that significant evidence supports the safety and effectiveness of bariatric surgery, few data are available on the outcomes of bariatric procedures in patients > or =65 years. The aim of this study was to report on contemporary outcomes of Roux-en-Y gastric bypass (RYGB) in patients > or =65 years. METHODS: We reviewed prospectively collected data from all patients > or =65 years who underwent RYGB at two Florida university-based programs from 1999 to 2005. Similarly, the Florida Discharge Database was queried for patients> or =65 years who had undergone RYGB from 1999 to 2005. The data are presented as the mean +/- SEM. RESULTS: A total of 25 patients > or =65 years had undergone RYGB at our institutions (age 68 +/- 1 years, body mass index 50 +/- 3 kg/m(2)). The overall complication rate was 20%, and the length of stay was 7 +/- 3 days. One patient (4%) died 5 weeks postoperatively of septic complications. For the 13 patients with a median follow-up of 21 months (range 9-61), the percentage of excess body weight loss was 51% +/- 7%; medication use for co-morbidities decreased from 9 +/- 1 to 4 +/- 1 medications/day (P <.01). The Florida Discharge Database reported 231 patients > or =65 years who had undergone RYGB. In that group of patients, the mean age was 67 +/- 0.2 years, the length of stay was 6 +/- 1 days, in-hospital mortality rate was 1.3%, and the overall complication rate was 15%. CONCLUSION: In a small cohort of patients > or =65 years, RYGB resulted in significant weight loss and resolution of obesity-related co-morbidities. The findings from the mandatory reported Florida Discharge Database strongly confirmed the safety of RYGB in patients > or =65 years.

Aged↗

PubMedDate not supplied

Peritoneal dialysis underutilization: the impact of an interventional nephrology peritoneal dialysis access program.

Peritoneal dialysis (PD) is an underutilized form of renal replacement therapy. Recent data have emphasized that only 12% of end-stage renal disease (ESRD) patients are initiated on this form of therapy in the United States. Patients requiring PD have most often been referred to general surgeons for catheter placement. This has incurred additional delays in starting treatment and loss of decision-making control by the referring nephrologist. To address this issue, we developed and incorporated our own PD access placement program into the preexisting chronic kidney disease (CKD) education program. To date, 46 patients have undergone 71 procedures. These included 51 (72%) PD catheter insertions, 14 (20%) removals, and 6 (8%) repositioning procedures for poor drainage. PD catheter insertion was performed peritoneoscopically under local anesthesia and a Fogarty catheter was used to reposition a migrated catheter. All of the procedures were performed by nephrologists in a dedicated interventional nephrology (IN) laboratory. All six repositioning procedures failed to restore optimal drainage. Five of these patients had the catheter removed and a new catheter placed during the same procedure. Of these five patients, one had recurrence of poor drainage and opted for hemodialysis (HD). The sixth patient declined reinsertion and chose HD. Of the remaining seven removal procedures, three were due to fungal peritonitis, one due to bowel perforation, one due to severe depression, one due to transplant, and one catheter was removed at the request of the primary physician in a terminally ill patient. Eight of the 51 catheter insertions were during the initial admission of a catastrophic dialysis start. Two of these patients started acute PD and avoided catheter placement for HD. Thirty-seven of 46 patients have a functional PD catheter with a follow-up of 8.6 +/- 0.8 (mean +/- SE) months. During an 18-month period our PD population has increased from 43 to 80 patients. We conclude that a dedicated PD access placement program coupled with a CKD education program can have a dramatic impact on patient choice and PD growth.

Adult↗

PubMedDate not supplied

Diagnostic and interventional nephrology.

The fragmented care of nephrology patients that results from referral to a radiologist for renal ultrasound (US) and biopsy, a surgeon for dialysis access placement, and an interventional radiologist for dialysis catheter placement and vascular access procedures often leads to delays in the treatment of these patients. Many specialists perform and interpret sonograms particular to their specialty rather than relying on technicians for performance and radiologists for interpretation, and nephrologists recently have begun to embrace this technology as an aid in the diagnosis and treatment of their patients. By combining an understanding of the pathophysiology of renal disease with the ability to perform clinical correlation and apply the laboratory data, the nephrologist is ideally suited to perform and interpret renal US and US guidance for percutaneous renal biopsies. Additionally, patients requiring peritoneal dialysis (PD) access have traditionally been referred to a general surgeon for catheter placement, which incurs additional delay in therapy and loss of decision-making control by the referring nephrologist. Recent data has emphasized that the peritoneal dialysis access procedure can be performed safely and effectively by a nephrologist trained in PD access procedures. Nephrologists also successfully perform tunneled hemodialysis catheter placement and vascular access procedures on an outpatient basis. The medical needs of patients with renal disease can be safely and efficiently delivered by a nephrologist trained in interventional nephrology (IN). This growing area of expertise will minimize delays, reduce cost, and allow physicians with training in the management of end-stage renal disease (ESRD) patients to be involved in the procedural aspects of their patients' care. An aggressive approach to the development of IN training programs at academic centers is warranted.

Adult↗

PubMedDate not supplied

Modification of the peritoneoscopic technique of peritoneal dialysis catheter insertion: experience of an interventional nephrology program.

Bowel perforation is a well-recognized complication of peritoneal dialysis catheter insertion and is associated with increased morbidity and cost of medical care. In this article we describe our 2-year experience (August 2001-October 2003) with a modified peritoneoscopic technique of peritoneal dialysis catheter insertion to minimize the incidence of bowel perforation. Seventy patients underwent 82 consecutive peritoneal dialysis catheter insertions using the innovative technique. The modified technique is very similar to the traditional peritoneoscopic procedure except for the following differences. To gain access to the peritoneal cavity, a Veress insufflation needle (Ethicon Endo-Surgery Inc., Cincinnati, OH) is utilized instead of the trocar. In contrast to the sharp tip of the trocar, the Veress needle has a blunt, self-retracting end. In addition, the Veress needle is only 14 gauge as opposed to the 2.2 mm diameter of the trocar. Upon introduction of the Veress needle into the abdominal cavity, two "pops" are discerned similar to the trocar. After introduction, 400-500 cc of air are infused and the needle is removed. The infusion of air creates a space between the peritoneal surface of the anterior abdominal wall and the bowel loops. At this point, the cannula with trocar is inserted into the space created. The rest of the steps of the procedure are the same as the traditional peritoneoscopic technique. Utilizing the innovative technique, all 82 catheter insertions were performed successfully without a single bowel perforation. No other complications except for catheter migration (n = 2) were noted. The extra cost of the needle (35 USD) should be viewed in the context of the costs associated with management of a bowel perforation. Large-scale studies are needed to confirm the superiority of this innovative technique over the traditional peritoneoscopic insertion found in our case series. In the interim, however, the increased morbidity and cost associated with bowel perforation calls for logical measures to be taken to avoid this dreaded complication.

Adult↗