Search PubMed⌕ Search

Biomedical subjects

L M Flint

Publications and source records attributed to L M Flint.

At least 73 records · Page 4Linked to original sources
PubMed1989

The role of pediatric surgery in the medical school curriculum.

In most medical schools, exposure to pediatric surgery is presented as a subspecialty elective. We have offered it as an integral part of the surgical clerkship for 10 years in the belief that it provides an excellent educational environment. To confirm this concept, the quizzes (Q), final examinations (FE), and grades of students assigned to the pediatric surgical service were prospectively studied. All students (N = 139) in the surgical clerkship entered the study. Thirty-two students were randomly selected and assigned to the surgical service of a major pediatric hospital (P-Surg) for 50% of their clerkship. The other students (N = 107) were assigned to a variety of adult surgical services (G-Surg) and served as the control group. All students attended the same seminars, used the same educational materials, were examined with the same test items, and were evaluated by the same oral examiners. Test items were electronically scored and the database was analyzed on an IBM computer. The statistical analysis was performed using a Student's t test and chi 2 analysis. There was no significant difference in the demonstrated cognitive performance and grades awarded to the two groups of students. We conclude that a pediatric surgical service provides an atmosphere that is educationally comparable to the adult general surgical service.

Curriculum↗
PubMed1989

Effect of pyruvate on regional ventricular function in normal and stunned myocardium.

The prolonged ventricular dysfunction following brief periods of coronary artery occlusion that does not produce irreversible damage has been termed the "stunned" myocardium. Although ventricular function returns to preischemic values by 1 to 7 days after reperfusion is established, inotropic therapy may be necessary to enhance contractility in the stunned heart. The purpose of this study was to determine the effect of pyruvate on ventricular function in normal and stunned myocardium. Eight chloralose/urethane anesthetized dogs were instrumented with ultrasonic crystals to measure systolic wall thickening in the left anterior descending artery (LAD) and left circumflex artery perfused regions of the left ventricle. Pyruvate (1 ml/min of 150 mM sodium pyruvate, pH 7.4) was infused directly into the LAD prior to and 30 minutes after a 10 minute LAD occlusion. Prior to LAD occlusion, LAD pyruvate infusion increased systolic wall thickening in the LAD-perfused region from 16.2% +/- 4.3% to 23.4% +/- 5.1% (p less than 0.05). Thirty minutes after LAD occlusion, regional wall thickening was depressed (3.3% +/- 2.6%; p less than 0.05), which is indicative of stunned myocardium. Subsequent LAD pyruvate infusion increased wall thickening in the stunned myocardium to 12.7% +/- 2.5%. The improvement of regional ventricular function was maintained only during the pyruvate infusion, as function returned to prepyruvate levels within 20 minutes after cessation of pyruvate infusion. These data indicate that pyruvate exerts a positive inotropic effect in normal and stunned myocardium. If pyruvate, a key intermediate in energy-producing pathways, exerts its inotropic effect through an enhancement of the energy state of the heart, it may have advantages over traditional inotropic agents in the treatment of postischemic contractile dysfunction.

Animals↗
PubMed1989

Organ injury scaling: spleen, liver, and kidney.

The Organ Injury Scaling (O.I.S.) Committee of the American Association for the Surgery of Trauma (A.A.S.T.) was appointed by President Trunkey at the 1987 Annual Meeting. The principal charge was to devise injury severity scores for individual organs to facilitate clinical research. The resultant classification scheme is fundamentally an anatomic description, scaled from 1 to 5, representing the least to the most severe injury. A number of similar scales have been developed in the past, but none has been uniformly adopted. In fact, this concept was introduced at the A.A.S.T. in 1979 as the Abdominal Trauma Index (A.T.I.) and has proved useful in several areas of clinical research. The enclosed O.I.S.'s for spleen, liver, and kidney represent an amalgamation of previous scales applied for these organs, and a consensus of the O.I.S. Committee as well as the A.A.S.T. Board of Managers. The O.I.S. differs from the Abbreviated Injury Score (A.I.S.), which is also based on an anatomic scale but designed to reflect the impact of a specific organ injury on ultimate patient outcome. The individual A.I.S.'s are, of course, the basic elements used to calculate the Injury Severity Score (I.S.S.) as well as T.R.I.S.S. methodology. To ensure that the O.I.S. interdiffuses with the A.I.S. and I.C.D.-9 codes, these are listed alongside the respective O.I.S. Both the currently used A.I.S. 85 and proposed A.I.S. 90 are provided because of the obligatory transition period. Indeed, A.I.S. 90 contains the identical descriptive text as the current O.I.S.'s. The Abdominal Trauma Index and other similar indices using organ injury scoring can be easily modified by replacing older scores with the O.I.S.'s.(ABSTRACT TRUNCATED AT 250 WORDS)

Abbreviated Injury Scale↗
PubMed1988

Early postoperative acute abdominal complications.

The detection and management of acute postoperative conditions of the abdomen present a challenge to the surgeon. Many of these conditions threaten life because of their association with disorders of oxygenation, circulatory stability, and infection leading to multiple organ failure. This discussion highlights features of rapid diagnosis and focuses on problems relating to the decision to reoperate for diagnosis and therapy.

Abdomen, Acute↗
PubMed1988

No elimination of aspiration pneumonia in neurologically disabled patients with feeding gastrostomy.

To clarify the relationship of aspiration pneumonia (ASP) to feeding gastrostomy in neurologically disabled patients, we reviewed the charts of 87 patients who had a feeding gastrostomy for enteral access. We looked for evidence of gastroesophageal reflux (GER) and ASP. Prior to gastrostomy, the frequency of ASP was 29 of 87 patients. One year after gastrostomy, the crude frequency of ASP (17 of 52 patients) was not significantly improved. After gastrostomy, ASP was still observed in 18 of the 29 patients in whom ASP had been identified prior to gastrostomy. In the 58 patients in whom there was no clinical evidence of ASP prior to gastrostomy, 17 demonstrated ASP after gastrostomy. Over-all, 39 of 87 patients died. Mortality at one year (32) was greater in patients with documented ASP (p = 0.025). The preoperative presence of GER was associated with postoperative ASP (predictive value of 0.70). The preoperative presence of both GER and ASP was associated with postoperative ASP in all of the patients we studied.

Adult↗
PubMed1987

Skeletal microcirculatory responses to hyperdynamic Escherichia coli sepsis in unanesthetized rats.

To determine the microvascular site of vasodilation during hyperdynamic sepsis, we measured arteriolar and venular responses to live Escherichia coli bacteremia in the rat cremaster muscle by direct in vivo videomicroscopy. Our data indicate that cardiac output (by thermodilution) increased, systemic vascular resistance decreased, and a differential arteriolar response occurred, with constriction of large arterioles and dilation of small terminal arterioles. We conclude that dilation of small terminal arterioles in skeletal muscle could contribute to decreased systemic vascular resistance during hyperdynamic sepsis. This may be an appropriate response to increased oxygen demand or decreased tissue utilization of oxygen. Alternatively, small-arteriole dilation may be an inappropriate response and secondary to release of vasoactive inflammatory mediators. If the latter is true, there is a potential therapeutic role for selective manipulation of the tone of small terminal arterioles in hyperdynamic sepsis.

Animals↗
PubMed1987

Penetrating arterial trauma. Analysis of missed vascular injuries.

From 1976 to 1981, 677 patients with potential vascular injuries from penetrating wounds to the upper and lower extremities and the neck were treated. Surgical exploration was used to evaluate 237 patients; 440 patients were evaluated by arteriography alone, with negative results. In the group that underwent surgery, there were 137 arterial injuries detected. Follow-up studies were performed to assess the rate of missed vascular injuries using each diagnostic modality. Short-term follow-up was obtained in 81% of all patients. Long-term follow-up, averaging 5.1 years, was obtained in 33% of the patients. Vascular injuries, which went undetected at the time of initial evaluation, were present in both the group evaluated by vascular exploration and the arteriography group. The combination of arteriography and exploration detected no missed injuries on follow-up.

Angiography↗
PubMed1985

Serum level monitoring of aminoglycoside antibiotics. Limitations in intensive care unit-related bacterial pneumonia.

Serum aminoglycoside assays have been accepted as useful methods of enhancing therapeutic efficacy in the treatment of intensive care unit-acquired pneumonia and in avoiding aminoglycoside nephrotoxicity. We prospectively studied 68 surgical patients with normal renal function and gram-negative bacterial pneumonia who were treated with aminoglycosides. Serum levels indicated subtherapeutic levels in 47 patients and verified optimum levels in 13 patients. Toxic trough levels developed in six patients and, despite immediate dosage adjustment, five patients suffered nephrotoxicity. Six additional patients also had nephrotoxicity. Five of these patients never had toxic peak or trough levels and rising trough levels developed in one patient after serum creatinine levels began to rise. We conclude that routine monitoring of serum levels effectively detects subtherapeutic antibiotic levels. This modality is useful for optimizing dosage schedules, but does not serve to predict or avoid nephrotoxicity in critically ill surgical patients.

Adolescent↗
PubMed1985

Effects of tissue acidosis on skeletal muscle microcirculatory responses to hemorrhagic shock in unanesthetized rats.

Arteriolar dilatation, loss of venous tone, and uptake of shed blood characterize decompensated hemorrhagic shock. The loss of compensatory constrictor responses to hemorrhage mainly occurs in the skeletal muscle microcirculation. Tissue acidosis may be an important mediator of this phenomenon. Using a decerebrate in vivo rat cremaster muscle preparation, we observed the microcirculatory responses to hemorrhagic hypotension with cremaster bath conditions of pH 7.4 and pH 7.0. Our data indicate that tissue acidosis attenuates constrictor responses of larger arterioles (100-170 micron) and venules to hemorrhagic hypotension but has no effect on the dilator responses of small arterioles (10-30 micron). We conclude that tissue acidosis contributes significantly to loss of arteriolar resistance and to decreased venous return in the decompensatory phase of hemorrhagic shock.

Acidosis↗
PubMed1985

Effective palliation of malignant biliary duct obstruction.

The efficacy of palliative biliary decompression by operative and percutaneous methods was evaluated in 106 patients with unresectable malignancies obstructing the biliary system. Seventy patients had operative and 36 had percutaneous decompression. Primary malignancies of the pancreas and bile ducts were most common. Percutaneous transhepatic decompression was achieved beyond the site of obstruction in 72% of patients. Overall hospital mortality was 25% for patients having percutaneous catheter decompression and 17% for those patients operated upon. Early postoperative death was significantly related to: (1) age greater than 70 years; (2) preadmission weight loss greater than 15 pounds; (3) prothrombin time prolonged more than 2.5 seconds; and (4) hepatic metastases. Major complications were encountered in 56% of survivors of percutaneous drainage and 36% of those surviving operation. Intubation of the bile ducts due to inability to bypass the obstruction at operation was associated with the highest mortality (50%) and morbidity (86%). Mean survival was 14 months after operation, compared to 5 months after percutaneous decompression. The authors concluded that percutaneous decompression of the biliary tree is useful palliative treatment for those patients with proximal biliary obstruction due to malignancy when estimated operative risk is high, but operative decompression offers most patients the opportunity for longer survival with lower ultimate mortality and morbidity.

Adult↗
PubMed1985

Determinants of outcome in pancreatic trauma.

Pancreatic injury remains a major source of morbidity and mortality. A previous review of this injury from our department confirmed that the failure to recognize major ductal injuries was a key element in poor outcome of these patients. We evaluated a treatment protocol in 72 consecutive patients that categorized injuries into one of four grades: grade I, pancreatic contusion or minor hematoma with an intact capsule and no parenchymal injury; grade II, parenchymal injury without major ductal injury; grade III, parenchymal disruption with presumed ductal injury; and grade IV, severe crush injury. All grade I and most grade II injuries were treated by drainage alone; the grade III and IV injuries were treated by pancreatic resection. Fifty-seven patients survived longer than 24 hours. There were 23 grade I patients. There were only minimal pancreatic complications and no deaths in this group. Of 18 patients with parenchymal injuries (grade II), only one death occurred, which was due to an inaccurate estimation of the degree of injury and delay in proper treatment. Sixteen patients with grade III and IV injuries were treated by resection with only one death, although the complications rose with increasing severity of the pancreatic injury. The mortality rate from pancreatic causes was 3% (2/57), a reduction from that in a previous report from our institution (19%). Our present study confirms the use of a vigorous diagnostic approach to pancreatic injuries, stresses the value of recognition of major ductal injury, and supports the utility of a treatment protocol in which clinical decisions are based on the severity of the pancreatic injury encountered.

Adult↗
PubMed1985

Emergency pneumonectomy for penetrating and blunt trauma.

Emergency pneumonectomy for penetrating and blunt trauma has an attendant high mortality. Patients with major lung injuries presenting with prolonged shock followed by control of bleeding, resuscitation with or without aortic cross-clamping and pneumonectomy have had uniformly unsatisfactory results. From 1972 to 1982, eight patients at the University of Louisville Hospital underwent emergency pneumonectomy. All patients underwent expeditious evaluation, resuscitation, and thoracotomy with pneumonectomy. Three patients died of exsanguination (2 patients had major associated intra-abdominal injuries). Three other patients died due to pulmonary edema and right ventricular failure 2 to 3 hours after hemorrhage had been controlled and intravascular volume restored. Aortic cross-clamping was employed in four patients due to persistent hypovolemia with 100 per cent mortality. Of the two surviving patients, one presented with stable blood pressure and had pneumonectomy for tracheobronchial disruption, while the other had pneumonectomy for tangential laceration of the lung at the hilum. Pulmonary edema and right ventricular failure were responsible for mortality following emergency pneumonectomy and control of hemorrhage and restoration of blood volume. The addition of aortic cross-clamping did not seem to alter survival and may, indeed, hinder therapy due to increased vascular afterload and increased heart failure and pulmonary edema.

Adult↗
PubMed1985

Epithelial lining methods in esophageal repair: a comparative study using pedicle flaps in cats.

Methods of restoring luminal lining in repair of partial-circumferential esophageal defects were evaluated to compare incidences of strictures and fistulas and quality of surface lining. In cats 50% and 67% circumferential esophageal defects were repaired by direct closure or pedicle flaps (latissimus dorsi) that were unlined (lining restored by epithelialization from wound margins) or that carried lining of normal skin (myocutaneous flaps), skin grafts, or mucosal grafts. Repairs were evaluated for esophagocutaneous fistulas, luminal stricture, flap luminal surface area, and quality of epithelial surface 6 weeks after surgery. Direct closure of 50% circumferential defects was as satisfactory as any flap repair method. Direct closure of 67% circumferential defects caused high incidences of fistulas and strictures, which were lessened by flap reconstructions. Among flap lining methods, normal skin (myocutaneous flaps) gave the lowest incidence of fistulas and strictures and the highest surface quality, but a high incidence of skin paddle loss occurred in this model. Split-thickness epithelial grafts were nearly as satisfactory as myocutaneous flaps, and less lining loss occurred. Epithelialization of unlined flaps gave the poorest results since lining was thin and often incomplete, and wound contraction produced loss of surface area and strictures. The findings are discussed from a perspective of wound healing physiology, and implications for clinical application are presented.

Animals↗
PubMed1984

Approaches to the management of shotgun injuries.

Shotgun wounds present specific challenges for the surgeon. Multiple penetrating wounds frequently involve large anatomic areas with potential multi-system injury. Experience with 121 patients sustaining shotgun wounds over the 5-year period ending 31 December 1981 was reviewed to assess results and evaluate treatment protocols. Sixty-six patients had chest wounds with pleural penetration. Twenty-four wounds were minor and were observed. Each had less than five pellets penetrating the pleura. Twenty-two patients had close-range injuries. Fourteen of these required chest tube drainage alone and eight patients required thoracotomy for control of bleeding. Eleven patients died, six as a direct result of the chest injury. In 55 patients with abdominal-retroperitoneal wounds exploratory operations were done if more than four pellets were thought to be lodged intraperitoneally or if signs of peritonitis were present, while lesser wounds without peritoneal findings were observed. In the 15 patients who did not have exploratory operations, there were no deaths or major complications. Thirty-five patients had exploratory operations. Two patients had five intraperitoneal missiles and no clinical evidence of peritonitis but were found to have significant intestinal perforations. Four patients died. Eighty-three patients with extremity wounds were classified according to location of injury. Forty-five had upper extremity wounds, with nine vascular injuries. Two patients died and one limb was amputated because of soft tissue infection. Thirty-eight patients had lower extremity wounds. Five had major vascular injuries. Preoperative arteriography was obtained in 13 patients with extremity injuries; the results of one of these were falsely negative. There were no deaths or amputations.(ABSTRACT TRUNCATED AT 250 WORDS)

Abdominal Injuries↗