The multi-disciplinary management of complex congenital and acquired tracheo-oesophageal fistulae

AIM OF THE STUDY

Complex tracheo-oesophageal fistulae (TOF) are rare congenital or acquired conditions in children. We discuss here a multidisciplinary (MDT) approach adopted over the past 5 years.

METHODS

We retrospectively collected data on all patients with recurrent or acquired TOF managed at a single institution. All cases were investigated with neck and thorax CT scan. Other investigations included flexible bronchoscopy and bronchogram (B&B), microlaryngobronchoscopy (MLB) and oesophagoscopy. All cases were subsequently discussed in an MDT meeting on an emergent basis if necessary.

MAIN RESULTS

14 patients were referred during this study period of which half had a congenital aetiology and the other half were acquired. The latter included button battery ingestions (5/7) and iatrogenic injuries during oesophageal atresia (OA) repair. Surgical repair was performed on cardiac bypass in 3/7 cases of recurrent congenital fistulae and all cases of acquired fistulae. Post-operatively, 9/14 (64%) patients suffered complications including anastomotic leak (1), bilateral vocal cord paresis (1), further recurrence (1), and mortality (1). Ten patients continue to receive surgical input encompassing tracheal/oesophageal stents and dilatations.

CONCLUSIONS

MDT approach to complex cases is becoming increasingly common across all specialties and is important in making decisions in these difficult cases. The benefits include shared experience of rare cases and full access to multidisciplinary expertise.

Double-blind randomized clinical trial of percutaneous endoscopic gastrostomy versus radiologically inserted gastrostomy in children

Background

The aim of this RCT was to determine whether radiologically inserted gastrostomy (RIG) in children is associated with more complications than percutaneous endoscopic gastrostomy (PEG).

Methods

Children at a single tertiary children's hospital requiring a primary gastrostomy were randomized to PEG or RIG. Patients were followed by assessors blinded to the insertion method. Complications were recorded, assigned a severity score, and analysed by zero-inflated Poisson regression analysis on an intention-to-treat basis, adjusting for length of follow-up.

Results

Over a 3-year period, 214 children were randomized (PEG, 107; RIG, 107), of whom 100 received PEG and 96 RIG. There was no significant difference in the number of complications between PEG and RIG groups (P = 0·875), or in the complication score: patients undergoing RIG had a 1·04 (95 per cent c.i. 0·89 to 1·21) times higher complication score than those who underwent PEG (P = 0·597). Only age had an independent significant effect on complication score, with older patients having a 0·97 (0·95 to 1·00) times lower complication score per year.

Conclusion

PEG and RIG are both safe methods of gastrostomy insertion with a low rate of major complications. Registration number: NCT01920438 (http://www.clinicaltrials.gov).

Umbilical hernia following gastroschisis closure: a common event?

PURPOSE

To assess incidence and natural history of umbilical hernia following sutured and sutureless gastroschisis closure.

METHODS

With audit approval, we undertook a retrospective clinical record review of all gastroschisis closures in our institution (2007-2013). Patient demographics, gastroschisis closure method and umbilical hernia occurrence were recorded. Data, presented as median (range), underwent appropriate statistical analysis.

RESULTS

Fifty-three patients were identified, gestation 36 weeks (31-38), birth weight 2.39 kg (1-3.52) and 23 (43 %) were male. Fourteen patients (26 %) underwent sutureless closure: 12 primary, 2 staged; and 39 (74 %) sutured closure: 19 primary, 20 staged. Sutured closure was interrupted sutures in 24 patients, 11 pursestring and 4 not specified. Fifty patients were followed-up over 53 months (10-101) and 22 (44 %) developed umbilical hernias. There was a significantly greater hernia incidence following sutureless closure (p = 0.0002). In sutured closure, pursestring technique had the highest hernia rate (64 %). Seven patients underwent operative hernia closure; three secondary to another procedure. Seven patients had their hernias resolve. One patient was lost to follow-up and seven remain under observation with no reported complications.

CONCLUSIONS

There is a significant umbilical hernia incidence following sutureless and pursestring sutured gastroschisis closure. This has not led to complications and the majority have not undergone repair.

Esophageal atresia and malrotation: what association?

INTRODUCTION

Esophageal atresia/tracheo-esophageal fistula (EA/TEF) has an incidence of approximately 1:3,500. The incidence of malrotation is thought to be 1:200-500. We attempted to define the incidence of a combination and discuss the implications.

METHODS

This was a retrospective review of all patients admitted to a single institution with a diagnosis of EA or EA/TEF or TEF between April 1981 and January 2013. Patients were included if the position of the duodeno-jejunal flexure (DJF) was determined by upper GI contrast study (UGIS), surgery or post-mortem.

RESULTS

Case notes were reviewed for 235 patients. In the EA type A group, 3/28 (11 %; 95 % CI 3.7-27.2 %) had malrotation, significantly higher than the reported incidence of malrotation in the general population (p = 0.0008). All three patients in this group were symptomatic with one patient found to have a volvulus at emergency surgery. In the type C group, 6/196 (3 %, 95 % CI 1.4-6.5 %) had malrotation, significantly higher than the incidence reported for the general population (p = 0.0033) but not significantly different to that of the type A group (p = 0.0878). There were no patients with malrotation identified in any other EA/TEF type. In total, 9/235 (3.8 %; 95 % CI 2.0-7.2 %) patients with EA had malrotation, significantly higher than the 5/1,050 (0.48 %) reported for the general population (p = 0.0002).

CONCLUSION

There is a high incidence of malrotation in patients with pure EA. In the type A group an attempt to identify the DJF position at gastrostomy siting and/or performance of UGIS in the neonatal period should be undertaken. There should also be a low threshold for UGIS in all EA/TEF patients.

The role of parenteral nutrition following surgery for duodenal atresia or stenosis

PURPOSE

In our institution, some children routinely receive parenteral nutrition (PN) following surgery for duodenal atresia/stenosis, while others do not. Our aim was to compare growth and infection rate between these two treatment strategies.

METHODS

This was a retrospective study of all children undergoing surgery for duodenal atresia/stenosis over 7 years.

RESULTS

Of the 54 children, 19 commenced PN soon after surgery (the 'Initial PN' group). Of the remaining 35 children, 13 (37 %) subsequently required PN (the 'Delayed PN' group). The remaining 22 never received PN (the 'Never PN' group). The proportion of patients experiencing clinically suspected sepsis was higher in those receiving PN ('Initial' plus 'Delayed'; 41 %) compared with those who never received PN (14 %; p = 0.04). The 'Initial PN' and 'Never PN' groups did not show a significant change in weight Z score over time. However, the 'Delayed PN' group showed a significant decrease in weight Z scores from the time of operation to the time of achieving full enteral feeds, and failed to catch up by the time of last follow-up.

CONCLUSION

Children with duodenal atresia/stenosis can be managed without PN. However, a third of these children subsequently require PN, lose weight centiles, and have a high rate of sepsis.

Consultant Versus Trainee Laparoscopic Pyloromyotomy: Is there a Difference in Outcome?

Infantile hypertrophic pyloric stenosis (IHPS) is a common cause of vomiting in infants. IHPS was a condition with significant associated mortality until 1912 when ramstedt introduced the operative procedure pyloromyotomy. Since then, mortality rates have reduced significantly owing to early recognition, correction of associated biochemical abnormalities and operative treatment. More recently, the management of IHPS has been modified by the introduction of the laparoscopic pyloromyotomy, first described almost two decades ago.

Randomized clinical trial of glutamine-supplemented versus standard parenteral nutrition in infants with surgical gastrointestinal disease

BACKGROUND

Addition of glutamine to parenteral nutrition in surgical infants remains controversial. The aim of this trial was to determine whether glutamine supplementation of parenteral nutrition in infants requiring surgery would reduce the time to full enteral feeding and/or decrease the incidence of sepsis and septicaemia.

METHODS

A prospective double-blind multicentre randomized clinical trial was performed in surgical infants less than 3 months old who required parenteral nutrition. Patients were allocated to treatment or control groups by means of minimization. Infants received either 0·6 g per kg per day alanyl-glutamine (treatment group) or isonitrogenous isocaloric parenteral nutrition (control group) until full enteral feeding was achieved. Primary outcomes were time to full enteral feeding and incidence of sepsis. Cox regression analysis was used to compare time to full enteral feeding, and to calculate risk of sepsis/septicaemia.

RESULTS

A total of 174 patients were randomized, of whom 164 completed the trial and were analysed (82 in each group). There was no difference in time to full enteral feeding or time to first enteral feeding between groups, and supplementation with glutamine had no effect on the overall incidence of sepsis or septicaemia. However, during total parenteral nutrition (before the first enteral feed), glutamine administration was associated with a significantly decreased risk of developing sepsis (hazard ratio 0·33, 95 per cent confidence interval 0·15 to 0·72; P = 0·005).

CONCLUSION

Glutamine supplementation during parenteral nutrition did not reduce the incidence of sepsis in surgical infants with gastrointestinal disease.

REGISTRATION NUMBER

ISRCTN83168963 (http://www.controlled-trials.com).

'See one, practise on a simulator, do one' - the mantra of the modern surgeon

Minimally invasive techniques are now well established in paediatric surgery. Training has traditionally been based on an apprenticeship model, as for open surgery. More recently the constraints of litigation, finance and restriction of doctors' working hours have led to a need to rethink this training. Simulation to learn and improve skills is by no means a new concept, but has been suggested as a way to address the above issues because it provides an ideal platform for acquiring the necessary skills for modern laparoscopic surgery. This paper explores some of the current issues of learning minimally invasive surgical skills in a simulated environment, and suggests that such simulation should not be seen in isolation but as a part of a wider and encompassing curriculum of learning for the 21st-century surgeon.

Surgical repair of incarcerated inguinal hernia in children: laparoscopic or open?

PURPOSE

The management of Incarcerated Inguinal Hernia (IIH) in children is challenging and may be associated with complications. We aimed to compare the outcomes of laparoscopic vs. open repair of IIH.

METHODS

With institutional ethical approval (09SG13), we reviewed the notes of 63 consecutive children who were admitted to a single hospital with the diagnosis of IIH between 2000 and 2008. Data are reported as median (range). Groups were compared by chi-squared or t-tests as appropriate.

RESULTS

· Open repair (n=35): There were 21 children with right and 14 with left IIH. 2 patients also had contralateral reducible inguinal hernia. Small bowel resection was required in 2 children. · Laparoscopic repair (n=28): All children had unilateral IIH (19 right sided, 9 left sided). 15 children (54%) with no clinical evidence of contralateral hernia, had contralateral patent processus vaginalis at laparoscopy, which was also repaired. The groups were similar with regard to gender, age at surgery, history of prematurity, interval between admission and surgery, and proportion of patients with successful preoperative manual reduction. However, the duration of operation was longer in the laparoscopy group (p=0.01). Time to full feeds and length of hospital stay were similar in both groups. Postoperative follow-up was 3.5 months (1-36), which was similar in both groups. 5 patients in the group undergoing open repair had serious complications: 1 vas transaction, 1 acquired undescended testis, 2 testicular atrophy and 1 recurrence. The laparoscopic group had a single recurrence.

CONCLUSION

Open repair of incarcerated inguinal hernia is associated with serious complications. The laparoscopic technique appears safe, avoids the difficult dissection of an oedematous sac in the groin, allows inspection of the reduced hernia content and permits the repair of a contralateral patent processus vaginalis if present.

Current status of prenatal diagnosis, operative management and outcome of esophageal atresia/tracheo-esophageal fistula

Ultrasonographic features suggestive of esophageal atresia with or without tracheo-esophageal fistula (EA/TEF) are only in a small minority of fetuses with EA/TEF (<10%) identifiable on prenatal scans.The prenatal diagnosis of EA/TEF relies in principle, on two nonspecific signs: polyhydramnios and absent or small stomach bubble. Polyhydramnios is associated with a wide range of fetal abnormalities, but most commonly it pursues a benign course. Similarly the sonographic absence of a stomach bubble may point to a variety of fetal anomalies.The combination of polyhydramnios and absent stomach bubble in two small series offers a modest positive predictive value of 44 and 56% respectively. Prenatal scanning for EA/TEF identifies a larger proportion of fetuses with Edwards syndrome; there is also a higher proportion of isolated EA in comparison to postnatal studies.Current ultrasound technology does not allow for a definite diagnosis of EA/TEF and therefore, counseling of parents should be guarded.Postnatal diagnosis of EA is confirmed by the failure to pass a firm nasogastric tube into the stomach; on chest X-ray, the tube is seen curling in the upper esophageal pouch. Corrective surgery for EA/TEF is well established and survival rates of over 90% can be expected.

Gastric emptying is accelerated following laparoscopic Nissen fundoplication

AIM OF THE STUDY

The effects on gastric motility following Nissen fundoplication in children are poorly documented. Some paediatric surgeons advocate additional procedures at the same time as fundoplication, such as a pyloroplasty, to enhance gastric emptying. The aim of this study was to determine whether laparoscopic Nissen fundoplication without pyloroplasty affects gastric emptying.

METHODS

Gastric emptying was measured before laparoscopic Nissen fundoplication in 8 children after ingestion of a standardised volume of milk for age mixed with 150 mg of (13)C-octanoic acid. None of the patients had a gastrostomy insertion at the time of fundoplication and 2 patients had neurological impairment. Breath samples were collected by breathing into a mask at baseline and every 15 minutes up to 3 hours, and were analysed for (13)CO (2)/ (12)CO (2) ratio by mass spectrometry. Gastric emptying time (t (1/2)) was derived from the curve of (13)CO (2)/ (12)CO (2) ratio against time. The test was repeated in 6 children following Nissen fundoplication at the time of full feeds. Data are reported as mean +/- SD and were analysed by the Mann-Whitney test.

RESULTS AND CONCLUSIONS

There were 4 males and 4 females; mean age at surgery was 3.3 +/- 3.0 years. Mean gastric emptying time was 59 +/- 17 min prior to laparoscopic Nissen fundoplication and 45 +/- 4 min following surgery (p = 0.03). Gastric emptying was accelerated in all except one patient. Gastric emptying for liquids is accelerated following Nissen fundoplication in children. Procedures aimed at improving gastric emptying time such as pyloroplasty or pyloromyotomy might not be justified at the time of laparoscopic Nissen fundoplication.

Laparoscopic and conventional appendicectomy in children: outcomes in English hospitals between 1996 and 2006

BACKGROUND

Laparoscopic appendicectomy is increasingly used in children. This national retrospective study compared outcomes of paediatric open and laparoscopic appendicectomy.

METHODS

Length of stay, readmission rates and mortality in children undergoing open and laparoscopic appendicectomy in English NHS Trusts between 1 April 1996 and 31 March 2006 were compared. Procedures coded as emergency excision of appendix (OPCS-4 H01) on the Hospital Episode Statistics (HES) database in patients less than 15 years of age were included. Multivariate analysis was used to identify independent predictors of length of hospital stay and mortality.

RESULTS

Eighty-nine thousand, four-hundred and ninety-seven (89,497) appendicectomies were studied; of which, 2,689 (3%) were performed laparoscopically. The percentage of laparoscopic cases rose from 0.6 to 8.4% between 1996 and 2006 (Pearson's r = 0.954, P < 0.001). Length of stay (median 3, interquartile range 2 days, P = 0.068) and 28-day readmission rates were similar (6.3 vs. 7.2%, respectively; P = 0.072) between groups. No independent hospital stay advantage for laparoscopy was observed (P = 0.121). No difference in 30-day mortality (P = 0.986) or 365-day mortality (P = 0.598) was demonstrated.

CONCLUSION

Hospital stay, readmission rates and mortality are similar following laparoscopic and open appendicectomy in children.

Umbilical polyp in infants and children

AIM OF THE STUDY

The umbilical polyp is a rare congenital lesion resulting from the persistence of omphalomesenteric duct (OMD) enteric mucosa at the umbilicus. Exploration of the abdomen to exclude the presence of associated OMD remnants is controversial. The aim of this study was to evaluate the need for peritoneal cavity exploration in children with umbilical polyp.

METHODS

All umbilical lesions (n = 53) excised between 1995 and 2005 in a single institution were reviewed to identify patients with umbilical polyp (n = 13). This is characterised histologically by the presence of gastrointestinal mucosa. A follow-up study of patients with umbilical polyp was performed. Data are reported as median (range).

RESULTS AND CONCLUSIONS

All 13 patients underwent excision of an umbilical polyp at a median age of 15.1 months (3.1 - 80.5). All presented with a discharging polyp (associated with bleeding in 9) which did not respond to topical silver nitrate. Median diameter of the lesions was 0.5 cm (0.2 - 1). Histology revealed the presence of small bowel mucosa in 11 (associated with pancreatic tissue in 1 and gastric mucosa in 1) and large bowel mucosa in 2. All patients underwent inspection and probing of the base of the polyp after its excision. In 6 patients an associated OMD anomaly was suspected and exploration of the peritoneal cavity was performed (mini-laparotomy in 5 and laparoscopy in 1). No OMD anomaly was found. The 7 children who did not undergo exploration of the abdominal cavity remain asymptomatic after 5.8 years (0.9 - 13.7) follow-up. An umbilical polyp can be present in the absence of other OMD anomalies. Exploration of the peritoneal cavity in children with an umbilical polyp does not seem to be necessary.

Surgical skills training in the laparoscopic era: the use of a helping hand

The aim of this study was to evaluate whether a training programme involving an assessment exercise performed on a laparoscopic trainer model leads to an improvement in the acquisition of laparoscopic skills in surgical trainees. Subjects were recruited from a cross-section of surgical trainees at the Great Ormond Street Hospital, Department of Surgery and the Institute of Child Health. All subjects completed both a baseline laparoscopic surgical skills questionnaire and three exercises on a new laparoscopic trainer model. Thirteen subjects completed both the baseline questionnaire and all three assessment exercises. These subjects exhibited a wide range of previous experience in laparoscopic surgery. Sixty-nine percent of subjects showed a significant improvement in the assessment exercise score with training (ANOVA; P = 0.01). Sixty-two percent of subjects showed a greater improvement between exercises 2 and 3 than between exercises 1 and 2. The difference in score between exercises 1 and 2 was not statistically significant (P = 0.597), whereas the difference in score between both exercises 2 and 3 and exercises 1 and 3 was statistically significant (P = 0.018 and P = 0.005, respectively). The double glove training model is thus a simple, inexpensive, and easily reproducible tool that elicits a significant improvement in laparoscopic surgical skills in surgical trainees with a broad range of previous laparoscopic experience. It can therefore be used as part of a training programme to facilitate the acquisition of laparoscopic skills in a paediatric surgery setting.

Absorption of carbon dioxide during laparoscopy in children measured using a novel mass spectrometric technique

BACKGROUND

Carbon dioxide (CO(2)) is absorbed during pneumoperitoneum and may cause adverse haemodynamic effects. The aim of this study was to measure the elimination of exogenous CO(2) during laparoscopy in children.

METHODS

Ten children [27.6 (56.5) months; mean (SD)] undergoing laparoscopic and nine [24.5 (17.3) months] undergoing open surgery were studied. Breath samples were collected at the line for end-tidal CO(2) and analysed for (13)CO(2)/(12)CO(2) ratio expressed as deltaPDB (difference from standard), by isotope-ratio mass spectrometry. The proportion of absorbed CO(2) was calculated comparing exhaled (13)CO(2)/(12)CO(2) before and during CO(2) pneumoperitoneum.

RESULTS

(13)CO(2)/(12)CO(2) in medical CO(2) was -32.7 (2.1) deltaPDB. (13)CO(2)/(12)CO(2) in breath of patients undergoing open procedures was -24.3 (2.4) deltaPDB at the start of operation and did not change during the operation (P > 0.2). (13)CO(2)/(12)CO(2) in breath of patients undergoing laparoscopy was -21.5 (5.4) deltaPDB at the start of insufflation, and decreased during pneumoperitoneum by 2.5 (1.6) deltaPDB, indicating absorption of exogenous CO(2). The percentage of expired CO(2) absorbed rose to 15.5 (7.7)% after 30 min of pneumoperitoneum and decreased rapidly after desufflation.

CONCLUSION

After 10 min of laparoscopy 10-20% of expired CO(2) derives from the exogenous CO(2). CO(2) absorption can be measured using a simple mass spectrometric technique.

Pilot study of new training model for laparoscopic surgery

The aim of this study was to evaluate whether an assessment exercise performed on a laparoscopic trainer model reliably reflects previous laparoscopic experience and can therefore be used to accurately assess laparoscopic skills in surgical trainees. Subjects were recruited from a cross-section of surgical trainees and students at the Great Ormond Street Hospital for Children and the Institute of Child Health. Subjects were required to complete a baseline laparoscopic surgical skills questionnaire and an exercise on a new laparoscopic trainer model. Nine subjects completed both the baseline questionnaire and the exercise. These subjects exhibited a wide range of previous experience in laparoscopic surgery. Subjects with higher self-assessment scores had the lowest exercise scores (i.e. better scores; P=0.003). Furthermore, the exercise score was strongly negatively correlated with the baseline number of training modalities received (P=0.007) and the laparoscopic experience score (P=0.027). The assessment exercise on a novel laparoscopic trainer was capable of differentiating between subjects with little laparoscopic experience and those with more extensive previous laparoscopic training. The correlation between the exercise score and measured baseline variables suggests that the scoring system used in this model is sensitive and specific to measuring skills relevant to laparoscopic surgery.

A multicenter, randomized, double-blind, placebo-controlled trial of the prokinetic agent erythromycin in the postoperative recovery of infants with gastroschisis

BACKGROUND/PURPOSE

The recovery of gut function after repair of gastroschisis is frequently prolonged, and these infants are prone to complications associated with parenteral nutrition. This trial was designed to investigate the effect of the prokinetic agent, erythromycin, on the attainment of full enteral feeding in infants after primary repair of uncomplicated gastroschisis.

METHODS

A multicenter, randomized, double-blind, placebo-controlled trial was used to investigate the effect of enteral erythromycin (3 mg/kg/dose 4 times daily) compared with placebo on the attainment of full enteral feeding tolerance after primary repair of uncomplicated gastroschisis. Eleven neonatal surgical units in the United Kingdom participated in the study. The primary end-point was the time taken to achieve continuous enteral feeding at 150 mL/kg/24 hours sustained for 48 hours.

RESULTS

Of 70 eligible infants, 62 were recruited and randomly divided. There were 30 patients in group I (placebo) and 32 in group II (erythromycin). The groups were comparable in terms of mean gestational age, mean birth weight, extent of evisceration, and degree of intestinal peel. There was no statistically significant difference between the 2 groups in the time taken to achieve full enteral feeding (27.2 v 28.7 days; P =.75). Similarly, no significant differences were found in the incidence of catheter-related sepsis, duration of parenteral nutrition, or time to discharge between the 2 groups.

CONCLUSIONS

Enterally administered erythromycin at a dose of 3 mg/kg 4 times daily conferred no advantage in the time taken to achieve full enteral feeding after primary repair of uncomplicated gastroschisis.

Range of motion after arthroplasty for the stiff osteoarthritic knee

In 28 of 1656 total knee arthroplasties (TKAs) (1.7%) performed for osteoarthritis at this institution, the preoperative arc of motion was 60 degrees or less (average 47.5 degrees; range, 20-60 degrees). The outcome of 22 of the 28 TKAs (21 patients) is reported at a mean follow-up of 52.9 months (range, 24-144 months). Eighty-two percent of the cases were managed with standard soft-tissue releases and posterior cruciate-retaining implants and 18% with a cruciate-substituting design. The joint score rose from 28.8 to 82.2 and the Knee Society Score from 24.6 to 77 points. The mean postoperative arc of motion improved by 46 degrees-93.5 degrees. At latest follow-up, 68.2% of knees achieved maximal flexion of 90 degrees or more. Manipulation was performed in 22.7%. Complications were minimal. A functionally useful range of motion is possible after total knee arthroplasty in the majority of stiff osteoarthritic knees, often without the need for posterior cruciate substitution.

Cementless cup fixation in total hip arthroplasty after 5-8 years

A series of 199 total hip arthroplasties was performed using a porous-coated, hemispherical press-fit acetabular cup. At a mean follow-up of 91.5 months 158 cups were available for clinical and radiological review. The mean age of the patients at the time of the index arthroplasty was 62.5 years. The mean Harris Hip score at final follow-up was 87.3. No shells were revised although eccentric polyethylene wear prompted liner replacement in two cases. Osteolysis was noted in six cases but predominantly in relation to the femoral stem. Focal pelvic osteolytic lesions were rare. All the cups were classified as stable on radiography.

Body mass index as a predictor of outcome in total knee replacement

The clinical and radiographic outcomes of 326 total knee replacements (TKR) in 285 osteoarthritic patients with body mass index (BMI) greater than 30 kg/m2 were compared with the results of a matched group of 425 TKR in 371 patients with BMI less than 30 kg/m2. At an average follow-up of 75.9 (48-144) months the Knee Society score (KSS) in the obese patients had increased by 41.9 points, and the joint score by 43.7. In the non-obese group the KSS rose by 40.2 points and the joint score by 42.6 points. Although patients with BMI greater than 40 kg/m2 achieved a lower final KSS the 'absolute improvement' appeared to be independent of BMI. Of the obese patient group 4.9% underwent a revision of their TKR, compared with 3.1% of the non-obese group. Although linear osteolysis (radiolucency) rates were comparable, focal osteolysis rates were 5 times those of control subjects when the BMI exceeded 40 kg/m2. Ten-year survivorship figures were similar for both obese and non-obese patients.

Review article: erythromycin as a prokinetic agent in infants and children

Erythromycin has been used as an antibiotic for more than four decades, but only in the last 10 years have other therapeutic benefits of this agent been exploited. Animal and human studies have demonstrated a prokinetic effect on the gastrointestinal tract at sub-antimicrobial doses (typically a quarter or less of the antibiotic dose). A limited number of studies have been performed in children to investigate this action. A review of this literature is particularly pertinent given the frequency of clinical problems related to gastrointestinal dysmotility in children and the limited availability of prokinetic agents in paediatric practice, compounded by the recent withdrawal of cisapride. The prokinetic effects of erythromycin have been investigated in infants with dysmotility associated with prematurity, in low birth-weight infants recovering from abdominal surgery, and in older children with a variety of other gastrointestinal disorders. Only one randomized placebo-controlled trial has been conducted. All except one of these studies have shown a beneficial effect of erythromycin in either promoting tolerance of enteral feeds or enhancing a measured index of gastrointestinal motility. Erythromycin appears to be equally effective when given orally (as ethylsuccinate or estolate) or intravenously (as lactobionate). Significantly, no serious adverse effects have been reported in studies in which erythromycin has been used for its prokinetic effects, although fatal reactions have followed the intravenous administration of erythromycin to neonates in antibiotic doses.

Results of all-polyethylene tibial components as a cost-saving technique

Since 1992, the authors have used an all polyethylene tibial component in relatively less active patients older than 70 years of age who present for primary total knee replacement. Results of 312 knee replacements performed between March 1992 and March 1998 are presented in the hopes of showing this technique as a viable cost saving measure. Three hundred twelve primary total knee replacements were performed by the same group of surgeons. Fourteen patients died before the first year postoperative evaluation, leaving an index group of 298 knees in 231 patients. All components were evaluated using the radiographic and clinical parameters of the Knee Society. Hospital for Special Surgery scores also were calculated. All patients were given the Short Form-36 Quality of Life Assessment preoperatively and annually postoperatively. Clinical scores showed dramatic improvement. There have been three revisions (0.7%) but none were for aseptic loosening. Radiographic review revealed 295 replacements with optimum fixation. To date, no patient has osteolysis. The cost differential was significant. The use of this type of tibial component has, to date, afforded excellent clinical and radiographic results. Additional followup is needed to show the longevity of these results and to monitor wear or subsidence of these prostheses. Should these results continue to prove satisfactory in this particular group of patients with relatively low physical demands, significant cost savings may be realized.

Cementless hemispheric acetabular component in total hip replacement

A series of 198 total hip arthroplasties was performed using a porous-coated, hemispheric press-fit cup. One hundred and twenty-seven cups were available for clinical and radiological examination at mean follow-up of 10.6 years. The mean age at the index procedure was 61.2 years. The mean Harris hip score at final follow-up was 89.8. Three cups were revised for aseptic loosening and two liners were changed for eccentric wear and pelvic osteolysis. Nine additional patients showed mild or suspected osteolysis. Two cups were rated "fibrous" stable. There was no correlation between additional screw fixation of the press-fit cup and osteolysis or revision.

Proximally porous coated femoral stem in total hip replacement--5- to 13-year follow-up report

A series of total hip replacements was performed using a proximally porous coated, tapered femoral stem system. At a mean follow-up of 8.1 (5-13) years, 80 out of 107 hips were available for clinical and radiological examination. The mean age at the index procedure was 58.6 years. The mean Harris Hip Score at final follow-up was 91.7. Radiological ingrowth was observed in 77 femoral stems, 2 stems were fibrous stable and 1 stem was loose.

Supracondylar nailing of distal periprosthetic femoral fractures

Seven patients who sustained complex distal femoral fractures above total knee arthroplasties all treated by supracondylar (retrograde) femoral nailing were retrospectively evaluated. All the patients demonstrated uncomplicated postoperative follow-ups and returned to weight bearing between 2 and 3 months after surgery. No delayed healing occurred and alignment of the femur was satisfactory.

The MACE procedure: experience in the United Kingdom

BACKGROUND/PURPOSE

The Malone Antegrade Continence enema (MACE) procedure has become commonplace in the treatment of patients with faecal incontinence and constipation. To ascertain its place in paediatric practice, the authors surveyed members of the British Association of Paediatric Surgeons (BAPS) to see if they have performed a MACE and continue to do so. The authors also assessed their indications, success rate, and complications.

METHODS

Members were asked to give the diagnosis of the patients submitted for surgery before September 1996, the procedure used to constructthe MACE, the rate of failure, and complications encountered.

RESULTS

A total of 300 MACE were reported, and the mean follow-up was 2.4 years. The diagnosis of 273 patients was known: spina bifida, 108; anorectal anomaly, 90; Hirschsprung's disease, 22; constipation, 23; other, 30. The most popular procedure was appendix disconnection and reimplantation. The overall success rate for all diagnoses was 79%. The main complication was stomal stenosis, 30%.

CONCLUSIONS

These figures confirm that MACE is a useful operation. Improved patient selection, improvement in techniques, and increasing knowledge regarding continued management should lead to improving results across the country.

The antegrade continence enema procedure why, when and how?

Following the description of the antegrade continence enema (ACE) 7 years ago, it has become widely performed and accepted as the most successful treatment for intractable faecal incontinence. Modifications of the operative technique and enema regimen have been described, but the basic principle remains. This paper traces the evolution of the ACE and describes criteria for patient selection, operative technique and enema regimens.

Detection and identification of Mycobacterium tuberculosis directly from sputum sediments by ligase chain reaction

Sputum specimens received for the diagnosis of tuberculosis or other mycobacterial infections were tested by a ligase chain reaction (LCR)-based assay and acid-fast stain and culture techniques. Results from the LCR assay (Abbott LCx Mycobacterium tuberculosis [MTB] Assay) were compared to results from standard culture techniques held for 6 weeks. Four hundred ninety-three specimens from 205 patients suspected of pulmonary tuberculosis were included in the prospective study. Thirty-four (6.9%) of the specimens were culture positive for M. tuberculosis, and 13 (38%) of these were also fluorochrome stain positive. LCR sensitivities and specificities compared to culture were 74 and 98%, respectively. LCR sensitivity was 100% for fluorochrome stain-positive specimens and 57% for fluorochrome stain-negative specimens. Nine LCR-negative, culture-positive specimens were the result of low concentrations of M. tuberculosis. No inhibitors were detected in any of these specimens. Of the eight LCR-positive, culture-negative specimens, five were from patients with active tuberculosis. With these considered culture misses, final LCR sensitivity, specificity, positive predictive value, and negative predictive value were 77, 99, 91, and 98%, respectively. The same performance values for the fluorochrome acid-fast bacillus smear were 33, 98, 62, and 94%, respectively. After normal laboratory sputum processing, the Abbott LCx MTB Assay can be completed in 6 h. Thus, it is possible to have results available within 8 h of specimen submission.

How to achieve a successful Malone antegrade continence enema

BACKGROUND/PURPOSE

The Malone antegrade continence enema (MACE) has proved invaluable in the management of children with faecal incontinence. The authors have reviewed their experience in depth to try and ascertain why some MACEs fail.

METHODS

The records of 31 children who had a MACE procedure between 1990 and 1995 were reviewed. Their preoperative bowel management, the operative procedure, the postoperative washout regime, and the outcome were assessed. Success was graded either as full, described as totally clean or minor rectal leakage on the night of the washout; partial, described as clean but significant stomal or rectal leakage, occasional major leaks, still wearing protection, and perceived improvement by the parents or child; or failure, described as regular soiling or constipation, no perceived improvement, and the procedure abandoned. There were 18 boys and 13 girls in the series. The mean age at survey was 8.4 years.

RESULTS

Overall success rate was 19 of 31 (61%) with a mean follow-up of 3.25 years. The diagnosis and success rates were: anorectal anomaly 11 (success, 8 of 11, 73%), neuropathic bowel 11 (8 of 11, 73%), chronic constipation 8 (3 of 8, 38%).

Amplification of rRNA for assessment of treatment response of pulmonary tuberculosis patients during antimicrobial therapy

The time course of persistence of Mycobacterium tuberculosis as measured by detection of rRNA, acid-fast bacillus (AFB) smear, and culture was determined for pulmonary tuberculosis patients during antimicrobial therapy. Twenty-three patients who were initially AFB smear positive and who subsequently completed a course of antimicrobial therapy were selected for the study. Sequential specimens were tested by AFB smear, culture, and rRNA amplification (Gen-Probe Amplified Mycobacterium Tuberculosis Direct Test [MTD]). The initial diagnostic specimens of all patients were positive by culture; those of 22 patients (96%) also were positive by MTD. Overall, MTD results remained positive longer than both smear and culture results. The median times to the last positive test result were 9 days for AFB smear, 26 days for culture, and 30 days for MTD. The last positive test result was the AFB smear result in 4% of cases, the culture result in 22%, and the MTD result in 52%. Fifty-six percent of patients had a period of shedding of noncultivable M. tuberculosis which was detected by MTD after culture results had converted to negative. This noncultivable period lasted 7 to 245 days. All three tests became reproducibly negative before the end of therapy and remained negative during follow-up for up to 1 year. These results indicate that during successful antimicrobial therapy, M. tuberculosis is eliminated in sputum samples as measured by amplification of rRNA, as well as by AFB smear and culture. No long-term rRNA carrier state was detected. While the time course of clearance of M. tuberculosis measured by rRNA overall was longer than with the two traditional tests, the rRNA test results allow sensitive and precise measurement of the clearance of noncultivable M. tuberculosis from respiratory specimens. This attribute may allow rRNA testing to be useful in clarifying patient response to antimicrobial therapy.

Detection and identification of Mycobacterium tuberculosis directly from sputum sediments by Amplicor PCR

Sputum specimens received for the diagnosis of tuberculosis or other mycobacterial infections were tested by a PCR-based assay and culture techniques. Results of the PCR assay (Amplicor Mycobacterium tuberculosis Test) were compared with results of standard culture techniques with cultures held for 6 weeks. One thousand nine specimens were included: 301 retrospective specimens (frozen at -70 degrees C and later tested by PCR) and 708 prospective specimens (tested within 1 day of processing). One hundred sixty-two (16%) of the specimens were culture positive for M. tuberculosis; 83 (51%) of these were also fluorochrome stain positive. The sensitivity and specificity of the Amplicor PCR compared with those of culture were 83% (134 of 162 specimens) and 97% (800 of 827 specimens), respectively. The sensitivity for fluorochrome stain-positive specimens was 99%, and that for fluorochrome stain-negative specimens was 66%. The great majority of the 28 PCR-negative, culture-positive specimens were low positives; 27 were smear negative and 19 contained < 100 CFU of M. tuberculosis per ml. The 27 PCR-positive, culture-negative specimens included 24 that were positive by repeat testing by alternate primer PCR and were from patients with tuberculosis on antimicrobial therapy. With these considered culture misses, the final sensitivities of PCR and culture were 85, and 87%, respectively, while the specificities were 99.6 and 100%, respectively. After normal laboratory processing of sputum specimens, the Amplicor PCR assay can be completed in 8 h. Thus, it is possible to have results available within 10 h of specimen submission.

Detection and identification of Mycobacterium tuberculosis directly from sputum sediments by amplification of rRNA

Seven hundred fifty-eight processed sputum sediments received for the diagnosis of tuberculosis or other mycobacterial infections were tested by utilizing a rRNA target amplification assay and traditional culture techniques. The results from the rRNA target amplification assay (Gen-Probe Amplified Mycobacterium Tuberculosis Direct Test), available in 5 h, were compared with the results from standard culture techniques held for 6 weeks. A total of 119 specimens (16%) were culture positive for Mycobacterium tuberculosis. Overall sensitivity, specificity, positive predictive value, and negative predictive value were 82, 99, 97, and 96%, respectively, for the Gen-Probe assay; 88, 100, 100, and 97%, respectively, for culture; and 53, 99.8, 99.6, and 91%, respectively, for fluorochrome stain. The Gen-Probe assay employs the isothermal enzymatic amplification of M. tuberculosis complex rRNA followed by detection of the amplicon with an acridinium ester-labeled DNA probe. This assay has the potential of reducing the time for diagnosis of tuberculosis to 1 day.

Evaluation of the 7-h membrane filter test for quantitation of fecal coliforms in water

The 7-h fecal coliform (FC) test for detection of FC organisms in water was evaluated to establish its validity and usefulness for emergency and disaster situations. The waters tested consisted of routine samples collected for public health surveillance and enforcement purposes. A total of 984 water samples from throughout California were assayed. These included samples from coastal salt waters, rivers, canals, and reservoirs, in addition to potable and miscellaneous freshwater sources. A portion of each sample was tested concurrently by both the 7-h FC test and the most-probable-number FC five-tube test. The 7-h FC test samples were incubated for 7 to 7.25 h at 41.5 degrees C. Overall, greater than 90% agreement was obtained between the methods in determining whether the water quality was acceptable or unacceptable. Statistical analysis of the 984 samples confirmed that the 7-h FC method was a suitable alternative to the most-probable-number FC method for evaluation of freshwater samples. During emergencies or disasters, the 7-h FC test could provide a means for detection of fecal contamination of water with results available in less than 1 day.

Effect of holding temperature on isolation of Neisseria gonorrhoeae

The effect of holding temperature on the recovery of Neisseria gonorrhoeae was studied. From 300 specimens tested, Thayer-Martin medium plates inoculated and incubated in the presence of CO2 at 35, 22, and 4 degrees C for 24 h before incubation at 35 degrees C yielded 100, 96, and 95% of all isolates ultimately recovered from 82 positive specimens. Although there was a decrease in the quantity of organisms recovered, initial incubation of specimens under refrigeration or at room temperature yielded greater than or equal to 95% of the positive specimens.