PubMed Health⌕ Search

Biomedical subjects

D A Lloyd

Publications and source records attributed to D A Lloyd.

At least 19 recordsLinked to original sources
PubMed1992

Serum electrolytes and capillary blood gases in the management of hypertrophic pyloric stenosis.

The purpose of this study was to assess whether the concentration of serum chloride and other variables, namely serum sodium, potassium and bicarbonate, can be used to predict metabolic acid-base status in infants with hypertrophic pyloric stenosis (HPS) and to assess whether such a prediction is influenced by the state of hydration. One hundred and sixty-three infants with HPS who had at least one set of serum electrolyte and capillary blood gas estimations performed after admission were studied retrospectively. A further 25 infants who had their electrolyte and blood gases measured after at least 12 h of rehydration and correction of the serum sodium and chloride abnormalities were studied prospectively. Stepwise multiple regression analysis, using standard bicarbonate as the dependent variable, revealed serum chloride concentration to be the most powerful independent predictor of standard bicarbonate level (r = -0.69, P less than 0.0001). Other variables did not improve the correlation significantly. In the retrospective study of untreated patients, the calculation of a 90 per cent prediction interval for the model indicated that if the serum chloride level is less than 96 mmol/l, one could be 95 per cent confident (one tail) that the patient was alkalaemic. To be 95 per cent confident that the patient was not alkalaemic, the serum chloride level would have to be greater than 121 mmol/l. The prospective study found that following rehydration a serum chloride level greater than or equal to 106 mmol/l more accurately predicted absence of alkalaemia. We conclude that predictability of acid-base status from measurement of serum chloride depends on the state of hydration of the patient.

Acid-Base Imbalance↗
PubMed1992

Quantitative and qualitative analysis of the extracellular matrix protein, laminin, in Hirschsprung's disease.

Previous immunohistochemical studies have shown an abnormal distribution of extracellular matrix (ECM) proteins, including laminin, in the smooth muscle layer of muscularis externa in Hirschsprung's disease (HD) bowel. These findings supported the hypothesis that an abnormal ECM microenvironment may be responsible for the failure of migration and/or development of the neural crest cells in the gut in HD. In order to determine the cause of the abnormality in laminin distribution, solid-phase enzyme-linked immunosorbent assays and immunoblots were used to quantitate the ECM protein laminin and characterize its subunits, respectively, in extracts of the dissected smooth muscle layer of the muscularis externa. In the aganglionic bowel, laminin (median concentration, 32.4 ng/mg of tissue) was found to be present in significantly greater quantity than in both the normoganglionic bowel of the same specimen (median, 17.2 ng/mg, P less than or equal to .05) and the normal bowel of age-matched controls (median, 9.7 ng/mg, P less than or equal to .05). Laminin concentration was also found to be significantly higher in normoganglionic HD bowel (median, 17.2 ng/mg) than in age-matched control specimens (median, 10.8 ng/mg, P less than or equal to .05). No difference was observed in the subunit composition of laminin in HD and control extracts analysed by immunoblot after polyacrylamide gel electrophoresis. This study demonstrates a quantitative abnormality of laminin in the bowel in HD, supporting the hypothesis that "abnormal microenvironment" may have a role in the pathogenesis of HD.

Blotting, Western↗
PubMed1991

Necrotizing enterocolitis following operation in the neonatal period.

Over a 16-year period, 33 newborn infants developed necrotizing enterocolitis (NEC) following some form of operation (accounting for 19 per cent of all neonates with NEC), including repair of myelomeningocele, intestinal atresia, gastroschisis and congenital diaphragmatic hernia. The neonates with postoperative NEC had a median birth-weight of 3.05 (range 1.0-4.4) kg, and median gestational age of 40 (range 27-41) weeks. Twenty patients were treated non-operatively. The remaining 13 required operation for complications of NEC. Twenty-three patients are alive and have been followed for a median of 66 (range 3-168) months. If a neonate deteriorates following any operation NEC must be included in the differential diagnosis.

Age Factors↗
PubMed1991

Gastroschisis, malrotation, and chylous ascites.

A newborn infant who had an uncomplicated repair of gastroschisis with modified Ladd's procedure developed chylous ascites when fed. After 7 weeks of nonoperative management with total parenteral nutrition, the ascites resolved. Widening the mesentery may have damaged the lymphatics, and is not necessary for malrotation associated with gastroschisis. Prolonged nonoperative management is recommended for neonatal chylous ascites, avoiding paracentesis if possible.

Abdominal Muscles↗
PubMed1991

Operation does not increase resting energy expenditure in the neonate.

This study was designed to assess the effect of operative stress on resting energy expenditure (REE) in surgical newborn infants. REE was measured in 15 neonates who had had an abdominal or thoracic operation. The findings were compared with the REE predicted from Talbot's data for unstressed neonates. The mean measured postoperative REE of 39.18 +/- 6.44 was not significantly different from the mean predicted REE of 40.98 +/- 8.83 kcal/kg/d. We concluded that an uncomplicated operation does not increase REE in the neonate.

Energy Metabolism↗
PubMed1991

The newborn with hydrops and sacrococcygeal teratoma.

The combination of fetal hydrops and sacrococcygeal teratoma (SCT), is considered to be lethal. We report two such babies who survived. Case 1 exhibited oliguric acute renal failure (ARF) immediately after birth, and severe respiratory insufficiency despite maximal ventilatory support and vasodilator infusions. Tumor resection on the 2nd day of life resulted in an immediate improvement in pulmonary function as reflected by the ratio of arterial to alveolar oxygen. Renal function returned in a pattern typical of recovery from acute tubular necrosis. Case 2, less desperately ill, developed nonoliguric ARF, in part due to deliberate fluid restriction during the 7 days that followed birth and preceded surgery. This resolved following liberalization of fluid intake that occurred at the time of tumor removal on the 7th day of life. The baby also had respiratory insufficiency that improved after surgery. Respiratory insufficiency may be a severe and life-threatening complication of SCT and hydrops fetalis. Pulmonary function may improve dramatically by removal of the tumor. Why this improvement occurs is unclear. Improvement of respiratory function may result from the elimination of excess tumor blood volume with an improvement of the ventilation-perfusion ratio. Alternatively, the tumor may be a source of vasoactive substances or extremely desaturated blood that leads to pulmonary hypertension and right-to-left shunting. Uncertainties in postnatal fluid shifts and exaggerated fluid compartment volumes demand close attention to details of renal function.

Acute Kidney Injury↗
PubMed1991

The effects of a hyperosmolar intravenous contrast medium on blood viscosity.

The effects of the hyperosmolar contrast medium, diatrizoate meglumine (Renografin-76) on blood viscosity and other metabolic parameters were measured in 20 immature piglets. Intravenous contrast medium caused a significant (P less than .5) increase in serum osmolality, cardiac output, and urine output, and a decrease in hematocrit. There was a fall in blood viscosity that was not statistically significant. These changes, which are attributed to an acute shift of fluid into the hyperosmolar vascular compartment, were greatest at 3 minutes following injection and subsequently returned towards baseline levels. We conclude that blood viscosity is not increased following intravenous injection of hyperosmolar radiocontrast media.

Animals↗
PubMed1991

Effective treatment of unresectable or metastatic hepatoblastoma with cisplatin and continuous infusion doxorubicin chemotherapy: a report from the Childrens Cancer Study Group.

The Childrens Cancer Study Group (CCSG) undertook a study (CCG-823F) to test the feasibility of administering continuous infusion doxorubicin (CI DOX) and cisplatin (CDDP) in patients with unresectable or incompletely resected hepatoblastoma (HB) or hepatocellular carcinoma (HCC). Chemotherapy consisted of CI DOX 20 mg/m2/d for days 1 to 4 and CDDP 100 mg/m2 on day 1 followed by a 21-day rest period. Second-look surgery was performed after the administration of four chemotherapy courses. Forty-seven (47) assessable patients were entered on study, 33 with HB and 14 with HCC; of these, 34 (26 HB and eight HCC) completed the initial four courses of chemotherapy. Of the 26 HB patients, 25 were evaluated as responding to chemotherapy before the scheduled second-look procedure and were considered surgically resectable at that time. Surgery was performed on 22 patients; three patients refused the second-look surgery. Nine patients had no evidence of residual malignant disease, seven underwent surgical resection of remaining tumor, four were left with microscopic residual disease, one had a partial resection with gross tumor left behind, and one remained unresectable. Nine HCC patients completed four chemotherapy courses. Eight patients achieved a partial remission and second-look surgery was attempted on seven. Only two had all malignant disease removed at the second procedure. Data from 225 courses of chemotherapy were evaluated for toxicity. Neutropenia (absolute granulocyte count less than 500/mL) was observed in 68 courses, and five of these episodes were associated with sepsis. Severe mucositis was documented in 21 courses, and hypomagnesemia (magnesium less than 1.2 mg) was noted in 30 patients. Two patients developed decreased left ventricular shortening fraction, which resolved when chemotherapy was discontinued. In summary, CI DOX plus CDDP is a well-tolerated and effective regimen in inducing surgical resectability in HB patients who are unresectable at diagnosis and significantly improves survival for this group of patients to 66.6%.

Adolescent↗
PubMed1991

Can medical education be researched?

Many medical educators are tempted or encouraged to conduct research into teaching techniques, methods of evaluation, and curricular change. These educators are generally career physicians who become distressed by their inability to apply the social science model of research to their project with impunity. This paper addresses the issues involved in conducting educational research and provides some suggestions for methodology that can be used.

Education, Medical↗
PubMed1991

Serum endorphin levels in injured children.

Plasma beta-endorphin levels (PBEL) are known to be elevated in acutely injured adults, but this has not been studied in pediatric patients with trauma. We measured PBEL in 46 children who sustained blunt injury. The mean acute PBEL was significantly elevated compared with the mean convalescent PBEL (40.5 +/- 29.0 versus 5.4 +/- 2.1 picomoles per liter, p less than 0.05). PBEL were highest in patients with multiple injuries (60.5 +/- 33.2 picomoles per liter, n = 16). PBEL were also elevated with isolated injuries of the head, face or limbs, and even with less severe injuries, namely multiple abrasions. PBEL were low in patients with abdominal (two patients) or spinal (two patients) injuries. Convalescent PBEL were consistently low. Severely injured patients (Injury Severity Score [ISS] of more than ten) had significantly elevated PBEL compared with patients with minor injuries (ISS less than 10), but some children with low ISS had elevated PBEL. The presence of head injury did not influence PBEL and there was no correlation between PBEL and systolic blood pressure. We have demonstrated that the PBEL is elevated in pediatric patients with trauma.

Acute Disease↗
PubMed1990

Renal venous thrombosis in infants and children.

Urgent nephrectomy was once considered standard therapy for renal venous thrombosis, but recently nonoperative therapy has been advised. To examine this trend more closely, we reviewed 46 cases of renal venous thrombosis seen at the Children's Hospital of Pittsburgh (Pa) over the last 32 years. Earlier, diagnosis was frequently supported by intravenous pyelography, which was 79% accurate. More recently, sonography confirmed the diagnosis with 92% accuracy. Of 21 patients diagnosed during life, 4 were treated operatively and 3 survived. Of 17 patients treated nonoperatively, 14 (82%) survived, including 5 with bilateral disease. Since 1978, of the 10 patients treated nonoperatively, 9 have survived with no long-term morbidity. Our experience confirms that early diagnosis with sonography followed by supportive nonoperative therapy offers the best chance for success in patients with renal venous thrombosis.

Child↗
PubMed1990

Preoperative stabilisation in congenital diaphragmatic hernia.

Between January 1983 and November 1986, 26 newborn infants with congenital diaphragmatic hernia were treated by early operation at a mean of 7 hours of age. A further 23 infants admitted between December 1986 and December 1989 were stabilised for a mean period of 40 hours before operation. There was no significant difference in survival between the two groups. Delayed operation is not detrimental to infants with congenital diaphragmatic hernia.

Diaphragm↗
PubMed1989

Topical treatment of burns using aserbine.

A cream containing malic, benzoic and salicylic acid esters (Aserbine) was evaluated as a topical dressing for dermal burns. Children with thermal injuries covering less than 20 per cent of the body surface area (BSA) were treated with Aserbine (53 patients), Daromide (31 patients) or silver sulphadiazine (SSD) (16 patients). In these groups, hot liquids were the cause of injury in 92 per cent, 100 per cent and 80 per cent of patients respectively. There were no significant differences in the numbers of patients with clinical evidence of infection. Aserbine did not inhibit the growth of staphylococci or Ps. aeruginosa, partly inhibited beta-haemolytic streptococci and Proteus sp., and completely inhibited the growth of E. coli. The rate of wound healing did not differ significantly between the groups. No toxic effects of Aserbine were observed, apart from transient discomfort on application. Aserbine is a safe, inexpensive topical agent suitable for thermal burns which are not heavily contaminated.

Anti-Infective Agents, Local↗
PubMed1989

Dura versus Gore-Tex as an abdominal wall prosthesis in an open and closed infected model.

Occasionally, it is necessary to use prosthetic material to close large abdominal wall defects in infected, potentially infected, or open wounds. We compared the effectiveness of Gore-Tex (PTFE, W.L. Gore & Associates, Flagstaff, AZ) and dura for closing large, full thickness abdominal wall defects in terms of resistance to infection, patch separation, and intraperitoneal adhesion formation. Ninety guinea pigs had full thickness, 2 cm2, abdominal defects patched with either PTFE or dura. The skin was (A) left open (B) closed over the patch under aseptic conditions, or (C) closed after wound contamination with 10(5) CFU of staphylococcus aureus. Wounds were examined daily and the wound and peritoneal cavity examined at necropsy (day 45). Patch separation, patch retention, and adhesions were similar in both open (A), and clean closed (B) wounds patched with PTFE or dura. In the infected closed wounds (C) of the PTFE animals, the incision remained intact significantly longer, the time of patch separation and overall patch retention were significantly increased, and bowel adhesions were significantly reduced compared to dura animals.

Abdominal Muscles↗
PubMed1988

Rhabdomyosarcoma in Roberts syndrome.

A 23-month-old child diagnosed as having Roberts syndrome, born to consanguineous parents, developed a sarcoma botryoides. Cytogenetic evaluation of peripheral blood lymphocytes and tumor cells showed premature centromere separation, which is characteristic of Roberts syndrome.

Abnormalities, Multiple↗
PubMed1988

Peritoneal drainage for necrotizing enterocolitis.

This study evaluates the role of primary peritoneal drainage (PPD) in the management of neonatal necrotizing enterocolitis (NEC). Of 169 patients with definite NEC, 92 (55%) underwent operation: primary laparotomy, 41 patients (45%); and PPD, 51 patients (55%). Seventeen (33%) of the PPD infants had subsequent laparotomy within seven days. Pneumoperitoneum was the indication for operation in 37% of the primary laparotomy and 67% of the PPD infants. Following PPD, 34 patients (67%) showed clinical improvement. Operative survivals were as follows: primary laparotomy, 83%; PPD, 53%. Infants who had PPD had a significantly lower mean birth weight, gestational age, preoperative pH and platelet count, and a significantly higher incidence of intraventricular hemorrhage and patent ductus arteriosus. For infants weighing less than 1,000 g at birth, the survival was similar following primary laparotomy (57%) and PPD (52%); this occurred in spite of the higher incidence of adverse risk factors in the PPD infants. For infants weighing greater than 1,000 g, the survival was 86% following primary laparotomy and 62% after PPD; in this group, all the early deaths following PPD occurred in critically ill infants who died within 48 hours of drainage. The late survival rates were as follows: primary laparotomy, 76%; PPD, 35%. More than half of the late deaths following PPD were not related to NEC, reflecting the difference between the two patient populations. Primary peritoneal drainage is a useful adjunct to resuscitation of the critically ill infant with complicated NEC, particularly prematures less than 1,000 g birth weight with intestinal perforation. Primary peritoneal drainage is not an alternative to laparotomy, which is recommended when an optimal clinical response has been achieved.

Drainage↗
PubMed1988

Adverse effects with oral 5-aminosalicyclic acid.

Two patients with ulcerative colitis and a past history of allergic reactions to sulfasalazine had similar reactions when treated with 5-aminosalicylic acid. This suggests that, at least in some patients, the adverse effects of sulfasalazine are due to 5-aminosalicylic acid rather than sulfapyridine. Desensitization to sulfasalazine was successfully carried out in one patient but was not attempted in a second.

Adult↗