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Biomedical subjects

R W Bailey

Publications and source records attributed to R W Bailey.

At least 37 records · Page 2Linked to original sources
PubMed1991

Laparoscopic cholecystectomy. Experience with 375 consecutive patients.

Three hundred seventy-five consecutive patients underwent laparoscopic cholecystectomy from September 1989 to January 1991. Three hundred forty-one (91%) presented on an elective basis, and the remaining 34 patients (9%) were admitted for acute cholecystitis (24), gallstone pancreatitis (9), and cholangitis (1). Of the 375 patients, 20 were converted to laparotomy and cholecystectomy, for an overall success rate of 95% for patients undergoing laparoscopic cholecystectomy. Three hundred nineteen patients (90%) were discharged within 24 hours of surgery. Operative cholangiography was completed in 141 patients, showing choledocholithiasis in five (managed by postoperative endoscopic retrograde cholangiopancreatography [ERCP] in 4, common bile duct exploration [CBDE] in 1). Two retained stones (0.9%) were detected in 214 patients not undergoing cholangiography. Three patients (0.8%) were reoperated on because of perioperative complications. Overall morbidity for patients undergoing laparoscopic cholecystectomy was 3.5%. Major complications (0.6%) included a single common hepatic duct injury and a delayed cystic duct leak at 10 days. Minor complications occurred in 11 patients (2.9%). The single perioperative death (0.3%) was due to a myocardial infarction on postoperative day 3, after an otherwise uncomplicated laparoscopic procedure. Laparoscopic cholecystectomy appears to offer significant advantages to patient recovery, and these data suggest that it can be performed with an efficacy, morbidity rate, and mortality rate similar to those of open cholecystectomy.

Adolescent↗
PubMed1991

Combined laparoscopic cholecystectomy and selective vagotomy.

Laparoscopic surgery offers distinct advantages to traditional surgery, including decreased hospitalization and recovery periods, decreased postoperative discomfort, and improved cosmesis. A feasible laparoscopic approach to the treatment of peptic ulcer disease might confer similar patient benefits. A modified highly selective vagotomy (in combination with cholecystectomy for symptomatic cholelithiasis) has been successfully completed under laparoscopic guidance in a patient with intractable ulcer disease. The patient was discharged on the second postoperative day, tolerating a regular diet. The patient's dyspeptic symptoms disappeared during the immediate postoperative period and further endoscopic evaluation revealed resolution of active ulcer disease. Although experience is still limited in the United States, initial clinical results from Europe would indicate that laparoscopic vagotomy is not only feasible but effective. With further experience, laparoscopic vagotomy may provide a viable alternative to the standard treatment of peptic ulcer disease.

Cholecystectomy, Laparoscopic↗
PubMed1991

Establishment of a laparoscopic cholecystectomy training program.

A recently developed alternative to traditional laparotomy and cholecystectomy is laparoscopic-guided cholecystectomy. This procedure has the advantages of reduced hospital stay, early return to work, diminished abdominal wall scarring, and less patient discomfort. The complex nature of this procedure and the current lack of extensive clinical experience preclude the traditional "hands-on" training normally practiced in surgical residency programs. At the University of Maryland, we have developed a program to instruct both surgeons and surgical residents in the techniques of laparoscopic surgery. Technical competence is achieved under the close supervision and guidance of an experienced laparoscopic surgeon. Training of residents in this procedure, therefore, is not very different than that for other general surgical procedures. Surgeons already in clinical practice, however, gain experience under somewhat different circumstances. Initial training involves didactic instruction through laparoscopic surgical atlases and educational videotapes. Further training uses a simulation device which enables the trainee to practice techniques of laparoscopic suturing, knot-tying, and clip application. Actual operative experience is acquired primarily in experimental animal preparations. Laparoscopic-guided removal of the gallbladder is performed in young swine (20-25 kg) under conditions that mimic those in the operating room. Further clinical experience can be acquired by assisting on several laparoscopic operations, usually involving diagnostic or pelvic procedures. Actual operative experience with laparoscopic cholecystectomy, of course, comprises the final phase of the educational program. The introduction of clinical laparoscopic training into general surgery residency programs should influence the widespread adoption of this new procedure.

Cholecystectomy↗
PubMed1987

Protection of the small intestine from nonocclusive mesenteric ischemic injury due to cardiogenic shock.

In a pericardial tamponade model of cardiogenic shock in pigs, we had previously shown that acute reductions in cardiac output produce severe mesenteric ischemia due to disproportionate splanchnic vasoconstriction. In this study, we extended the period of cardiogenic shock in order to investigate the pathogenesis of ischemic injury to the small intestinal wall. Four hours of tamponade produced sustained changes in splanchnic hemodynamics, similar to those observed in the prior short-term experiments. The resultant mesenteric ischemia caused necrotic lesions of the small intestine which were characteristic of those seen in nonocclusive mesenteric ischemia in human subjects. Prior alpha-adrenergic blockade failed to prevent either sustained mesenteric vasospasm or ischemic injury. In contrast, prior blockade of the renin-angiotensin axis, whether by nephrectomy or angiotensin-converting enzyme inhibition, blocked the splanchnic vasoconstriction, and thereby protected the small intestine from ischemic injury. The primary hemodynamic and pathologic features of this model of nonocclusive mesenteric ischemia appear to be mediated by the renin-angiotensin axis.

Animals↗
PubMed1987

The fundamental hemodynamic mechanism underlying gastric "stress ulceration" in cardiogenic shock.

Acute hemorrhagic ulceration of the gastric mucosa is seen frequently in patients with hypovolemic or cardiogenic shock. Although such lesions clearly are related to regional gastric ischemia, little attention has been directed at the underlying mechanism(s) mediating the ischemia itself. To this end, anesthetized pigs were subjected to sustained cardiogenic shock (mild hemorrhage and pericardial tamponade) such that cardiac output was reduced to 38 +/- 1% of the baseline level for 4 hours, followed by release of the tamponade, reinfusion of the shed blood, and resuscitation for 2 hours. During the period of shock, there was profound regional gastric ischemia, resulting from severe and disproportionate gastric vasoconstriction. "Blinded" gross and microscopic evaluation of the stomachs removed after the experiment revealed severe mucosal ischemic necrosis, hemorrhage, and ulceration, whereas sham-operated pigs showed no lesions. The characteristics of this model therefore mimic the essential features of the gastric "stress ulceration" syndrome. Prior confirmed total alpha-adrenergic blockade with phenoxybenzamine failed to alter these features significantly. In contrast, prior ablation of the renin-angiotensin axis, whether by angiotensin-converting enzyme inhibition with teprotide or by bilateral nephrectomy, significantly and substantially ameliorated the ischemia, vasospasm, and mucosal injury. In this model of cardiogenic shock, acute gastric mucosal "stress ulceration" is caused by a disproportionately severe regional gastric ischemia resulting from selective splanchnic vasospasm that is unaffected by sympathetic blockade but abolished by prior ablation of the renin-angiotensin axis. Like nonocclusive small bowel ischemia, ischemic colitis, and the "shock liver" syndrome, gastric "stress ulceration" is yet another component of the multiple splanchnic organ failure syndrome that appears to be mediated primarily by the remarkable sensitivity of the splanchnic vascular bed to the renin-angiotensin axis.

Animals↗
PubMed1986

Pathophysiology of hepatic ischemia in cardiogenic shock.

The hepatic hemodynamic response to cardiogenic shock was investigated in a porcine model produced by pericardial tamponade to better understand the pathophysiology of postshock hepatic insufficiency. Reductions of cardiac output to 50 percent of baseline levels produced marked hepatic ischemia by causing disproportionate reductions in blood flow through the celiac and hepatic arteries and portal vein. These were due to selective vasoconstriction of the splanchnic resistance vessels that was mimicked without tamponade by the infusion of angiotensin II, ablated by angiotensin-converting enzyme blockade, unaffected by alpha-adrenergic ablation, and correlated closely with levels of plasma renin activity. The ischemic liver injury of cardiogenic shock appears to be largely due to an exquisite responsiveness of the splanchnic vascular smooth muscle to endogenously released angiotensin II.

Angiotensin II↗
PubMed1986

Pathogenesis of nonocclusive ischemic colitis.

The nonocclusive component of ischemic colitis in anesthetized pigs was mimicked using cardiogenic shock produced by pericardial tamponade. Increases in pericardial pressure produced decreases in arterial pressure (PA) and cardiac output (CO), with corresponding rises in total peripheral resistance (i.e., cardiogenic shock). This was associated with marked reductions in blood flow through the inferior mesenteric artery (IMA), due primarily to disproportionate increases in IMA vascular resistance. Levels of plasma renin activity correlated closely with these changes in mesenteric hemodynamics. Confirmed, total alpha adrenergic blockade with phenoxybenzamine failed to block this selective mesenteric vasoconstriction, while ablation of the renin-angiotensin axis with captopril completely abolished it, thereby ameliorating the colonic ischemia. Central intravenous infusions of pathophysiologic levels of angiotensin II, without tamponade, mimicked the response to shock seen with tamponade alone. In an additional group of pigs, 4 hours of sustained shock (tamponade) followed by 2 hours of normotension (release of tamponade and resuscitation) produced lesions characteristic of ischemic colitis, including full-thickness mucosal ulceration. Such lesions were ameliorated significantly in pigs in which the renin-angiotensin system had been ablated by bilateral nephrectomy. Nonocclusive ischemic colitis appears to be mediated primarily by a remarkable sensitivity of the colonic vasculature to the renin-angiotensin axis.

Animals↗
PubMed1985

Control of gastric vascular resistance in cardiogenic shock.

That local splanchnic ischemia is associated with the acute gastric "stress" erosions seen in shock is well established. The hemodynamic mechanism mediating that ischemia is unknown. Pericardial tamponade was produced in anesthetized pigs while hemodynamic parameters were monitored in the systemic circulation as a whole and in the vascular beds of the celiac and left gastric arteries, respectively. Stepwise increases in pericardial pressure produced progressive decreases in arterial pressure and cardiac output (i.e., reproducible, quantitable, and rapidly reversible levels of cardiogenic shock). This produced a profound reduction in blood flow in the celiac and gastric beds that was significantly disproportionate to the reduction in cardiac output. This was due to significant increases in celiac and gastric vascular resistance that were more than twice as great as those seen in the systemic circulation as a whole (i.e., selective splanchnic vasoconstriction). This response was abolished by ablation of the renin-angiotensin axis, whether by bilateral nephrectomy, captopril, or saralasin, and mimicked, without tamponade, by the infusion of angiotensin II. Levels of celiac artery blood flow and resistance correlated significantly with endogenous levels of plasma renin activity. On the other hand, this response was not abolished by confirmed alpha-adrenergic blockade (phenoxybenzamine) or by sympathectomy. In this model, cardiogenic shock produces regional splanchnic ischemia in the celiac and gastric vascular beds by inducing a severe and disproportionate vasospasm that is mediated primarily by the renin-angiotensin axis.

Animals↗
PubMed1985

Long-term results of tibiotalar arthrodesis.

One hundred and one tibiotalar arthrodeses were performed using a single surgical technique that has not been previously reported. The average follow-up was ten years (range, two to twenty-five years). The rate of pseudarthrosis was 5 per cent, four to five times less than in other recent large reports. Pseudarthrosis occurred only in patients with a sensory deficit. Secure fusion was radiographically documented in 95 per cent and the functional clinical result was good to excellent in 90 per cent. The ideal fusion position was found to be neutral or slight equinus angulation, and varus-valgus angulation equal to that of the contralateral side. More than 7 degrees of varus angulation of the heel was associated with symptomatic lateral metatarsalgia in all feet in which it occurred. Radiographic measurement documented an average 85 per cent (11-degree) increase in postoperative tarsal motion. Neither symptoms nor function correlated with the degree of tarsal hypermobility.

Adolescent↗
PubMed1981

Internal fixation of the femur in patients with osteogenesis imperfecta.

The operation of fragmentation and intramedullary rod fixation of the femur with an extensible device has proved valuable for children with osteogenesis imperfecta because it permits these children to remain ambulatory. The use of an extensible rather than a solid rod has greatly decreased the need for reoperation.

Child↗
PubMed1981

Evolution of the concept of an extensible nail accommodating to normal longitudinal bone growth: clinical considerations and implications.

Based on animal experiments, we observe that the central portion of an epiphysis can be subjected to acute trauma in a low order of its cross-sectional area without interfering with growth. Moreover, the presence of a metallic device of small diameter placed across the center of the distal femoral epiphysis of a growing dog does not interfere with growth. A metal pin with a T-shaped end can be placed across the distal femoral epiphysis of a growing dog with the T-shaped end fixed in the epiphysis without interfering with growth. As growth occurs, migration of the spin or elongation of the femur beyong the pin does not occur. On the contrary, the T-shaped device, because of fixation of the end of the T, is passively carried along with the epiphysis as the femur elongates with growth. Based on the above experiments, an extensible fixative device was developed which would elongate with the distracting force of growth. The nail responded to these forces, elongating with femoral growth and did not retard growth. Microscopic analysis of the nail tracts across the epiphyseal plates showed no tendency to premature closure of the epiphyseal line. The tracts formed by the nails were lined with fibrous tissue; the remainder of the epiphysis showed a normal histologic structue.

Animals↗
PubMed1981

Further clinical experience with the extensible nail.

The extensible nail for treatment of children with brittle bones offers distinct advantages over the conventional rod. It appears to elongate with growth and thus obviates periodic replacement of the rod as the child grows. Complications have been few in this and other series. Recent modifications of the technique for the femur and tibia, and various changes in the original design, constitute significant improvements in the intramedullary nail method.

Adolescent↗
PubMed1979

Transarticular fixation in the treatment of non-union of supracondylar fractures of the femur: a salvage procedure.

We treated eleven non-unions of a supracondylar fracture of the femur with application of a bone graft and fixation with a Küntscher intramedullary rod driven across the knee joint. In ten of the eleven patients the fracture united and the patients obtained stability, relief of pain, and, in two patients, an increased range of motion of the knee. Most surgeons use the blade-plate or the compression screw for fixation, but the intramedullary nail may be a better device and may simplifty the surgical procedure.

Adult↗
PubMed1978

Plant cell wall fractionation and structural analysis.

The structure of the major plant polysaccharides contributing to dietary fiber, their organization within the plant cell wall, and the problems associated with their analysis are briefly reviewed. Alkaline, acidic, and detergent fractionation methods are described and considered in relation to their specificity. The analysis of pectin, often ignored as a component of dietary fiber, is examined in detail. The solubility of pectins from a number of common plant foods was determined, indicating that a considerable portion of pectin polyuronide is lost to many of the commonly used analytical procedures.

Cell Wall↗
PubMed1977

Fatal colitis in a hemophilic patient with inhibitor.

A severe colitis developed in a hemophilic patient following an antibiotic regimen which included clindamycin. A surgical procedure, total hip replacement, had been complicated by the appearance of a powerful factor VIII inhibitor and a Bacteroides fragilis infection. The resulting bleeding diathesis was successfully managed with the use of an "activated prothrombin complex"; however, the occurrence of colitis following intravenous clindamycin therapy proved to be fatal. Clindamycin, like the related antibiotic lincomycin, appears to have significant intestinal toxicity and should be restricted to the treatment of life-threatening proven Bacteroides infections.

Adult↗
PubMed1976

Spondylolisthesis: indications for lumbar nerve root decompression and operative technique.

Pain mechanisms attributable to spondylolisthesis are discussed with particular regard to the anatomic relationships at the site of nerve root impingement where the exiting lumbar nerve root is noted to pass anterior to the pseudoarthrosis mass in the pars interarticularis portion of the posterior element of the vertebral body. Clinical findings support the fact that nerve root impingement is a definite factor in producing the pain and associated symptoms in root impingement further supports this hypothesis. The incidence of lower motor neuron deficit is determined by a combination of muscle testing and electromyography. Postoperative results are evaluated in terms of patients having arthritic changes associated with the spondylolisthesis and in those patients with absence of arthritic change. These changes distinguish the patients who might respond best to simple decompression of the nerve root impingement from those patients who might better benefit from spinal fusion. Operative techniques should include adequate decompression of the exiting lumbar nerve root by means of total laminectomy approach. Exision of the pseudarthrosis mass attached to the pedicle side of the pars interarticularis of the vertebra is necessary to relieve pressure on the shoulder of the exiting nerve root.

Adolescent↗