The Cardiovascular, Coagulation and Haematological Effects of Tiger Snake (Notechis scutatus) Prothrombin Activator and Investigation of Release of Vasoactive Substances

The cardiovascular, coagulation and haematological effects of prothrombin activator from Tiger Snake (Notechis scutatus) venom were investigated in anaesthetized mechanically ventilated dogs. Infusion caused dose-related systemic hypotension, marked decreases in cardiac output and stroke volume, marked increases in pulmonary artery pressure, pulmonary artery occlusion pressure and pulmonary vascular resistance. Effects occurred within several minutes but abated over 30 to 40 minutes. Evidence of procoagulation included prolongation of prothrombin and partial thromboplastin times and depletion of serum fibrinogen. Thrombocytopenia and leucopenia occurred. All effects were prevented by prior administration of heparin but none by inhaled nitric oxide. Oesophageal echocardiography during infusion identified thrombi within the heart, right ventricular dilatation and dyskinesia. Electrocardiography suggested myocardial ischaemia. Pulmonary thromboemboli were identified histologically post mortem. Cardiovascular effects of the activator were not due to a variety of endogenous substances as indicated by use of antagonists to platelet activating factor and thromboxane A2, indomethacin, dexamethasone, serotonin, ketanserin, histamine, promethazine and ondansetron. Tiger Snake prothrombin activator causes bilateral ventricular failure by thrombotic obstruction of the pulmonary vasculature and possibly by coronary ischaemia.

Effect of Different Surface Treatments and Adhesives on Repair Bond Strength of Resin Composites After One and 12 Months of Storage Using an Improved Microtensile Test Method

Objectives

To evaluate the effect of surface treatments and bonding systems on the repair bond strength between composite materials after one and 12 months of storage, using an improved microtensile test method.

Methods

A total of 72 composite cylinders (Tetric Evo Ceram, Ivoclar) were fabricated, stored in distilled water for two weeks followed by thermal cycling (5000 times between 5°C and 55°C), and served as substrate. The cylinders were mechanically roughened using 320-grit silicon carbide sandpaper, etched with 37% phosphoric acid gel, rinsed with water, and divided equally into three experimental groups: group 1, unchanged surface; group 2, sandblasting of the surface (CoJet tribochemical silica sand, 3M ESPE; Microetcher II, Danville Engineering Inc); and group 3, surface silane coating (Bis-Silane, BISCO Inc). Eight control cylinders were prepared and underwent similar aging as the substrate. Each experimental group was divided into subgroups that received the following bonding systems: one-step self-etching adhesive (AdheSE One, Ivoclar Vivadent), two-step self-etching adhesive (Clearfil SE, Kuraray America), and three-step etch-and-rinse adhesive (Adper Scotchbond Multi-Purpose, 3M ESPE). Fresh composite (Tetric Evo Ceram, Ivoclar) was placed and cured on top of the prepared substrate cylinders. The specimens were placed in distilled water for a week and thermocycled the same way as before. Eight composite control cylinders were also stored and thermocycled for the same period of time. Half of the cylinders in each test group were tested at one month and the second half at 12 months. The cylinders were serially sectioned in an automatic cutting machine, producing 10 to 20 1.1 × 1.1-mm test specimen beam from each cylinder. Specimens were prepared for microtensile testing and the tensile strength calculated based on the force at fracture and specimen dimension. The fracture surfaces were examined under a stereomicroscope and the type of fracture noted.

Results

The mean tensile strength of composite control was 54.5 ± 6.0 MPa at one month and 49.6 ± 5.1 MPa at 12 months. The mean tensile strength for the repaired groups ranged from 26.4 ± 6.8 MPa to 49.9 ± 10.4 MPa at one month and 21.2 ± 9.9 to 41.3 ± 7.5 at 12 months. There was a statistical difference between all groups (p<0.05) at one month. This difference was less pronounced at 12 months. The highest repair strength was obtained in the group having a silane-coated surface and Clearfil, the two-step self-etching adhesive. Clearfil also had the highest repair strength within each surface treatment group. There was a tendency for lower tensile strength at 12 months compared with one month. Most fractures were of the adhesive type; the highest number of cohesive fractures, 16% at one month and 12% at 12 months, were in groups with the highest tensile strength.

Conclusion

The best repair bond strength was achieved by using freshly mixed silane solution on the substrate in addition to an adhesive, rendering a thin bonding layer.

Comparison of a Trigger Tool and Voluntary Reporting to Identify Adverse Events in a Paediatric Intensive Care Unit

Reduction of adverse events depends on accurate detection. The utility of a Trigger Tool to detect and classify severity of adverse events in an intensive care unit of a paediatric university hospital was compared to voluntary reporting. Sixty patient records were randomly selected from 314 admissions over three months. Events detected by the Trigger Tool were classified by two independent investigators as insignificant, minor, moderate, major or catastrophic. Examination of each record required, on average, 40 minutes. Ninety-eight adverse events (1.66/patient) were detected in 59 available records. Mean admission was 2.77 days. The incidence of adverse events was 59.9 per 100 patient days or 0.60 events per patient per day. The number of events detected by the Trigger Tool was related to duration of admission (r=0.70, P < 0.0001) and risk of mortality on admission (r=0.50, P=0.0001) but not to age. The inter-rater agreement on detection of adverse events was good. Investigator One detected 66 adverse events while Investigator Two detected 93 events (kappa 0.63). Of the 61 events detected by both investigators, the agreement of classification of severity was very good (kappa 0.89). Of the 56 events rated similarly by both investigators, 13 (23%) were insignificant, 19 (34%) were minor, 17 (30%) were moderate, 4 (7%) were major and 3 (6%) were catastrophic. Only four adverse events had been reported voluntarily, of which two were detected using the Trigger Tool. Whereas the Trigger Tool is a simple, efficient and robust method, voluntary reporting is inadequate and captures very few adverse events in the intensive care unit environment.

Leukocytotic pseudohypoxaemia

A case of hypoxaemia was concluded to be a pseudo-condition after investigation demonstrated that the hypoxaemia was not related to lung disease, but rather to the time expiring between obtaining and analysing blood samples and to a reduction in the magnitude of the patient's white cell count.

Epidemiology of paediatric out-of-hospital cardiac arrest in Melbourne, Australia

BACKGROUND

Previous studies of paediatric cardiac arrest have reported a low survival rate but there is limited data from Australia. We sought to determine the characteristics and outcomes of paediatric out-of-hospital cardiac arrest in Melbourne, Australia.

METHODS

Between October 1999 and June 2007, all cases of out-of-hospital cardiac arrest attended by emergency medical services in Melbourne, Australia were entered into a database (the Victorian Ambulance Cardiac Arrest Registry). Data on patients aged less than 16 years in cardiac arrest on arrival of ambulance paramedics was analysed.

RESULTS

There were 209 children in cardiac arrest on arrival of paramedics during the study period. Of these, resuscitation was not attempted in 16 children due to signs of definite death. Of the 193 children who had attempted resuscitation, 143 (74%) had an initial cardiac rhythm of asystole, 36 (18%) were in pulseless electrical activity and 14 (7%) were in ventricular fibrillation. There were 49 patients (25%) with return of spontaneous circulation at arrival to hospital of whom 14 (7%) survived to hospital discharge. Of 138 patients without return of a circulation, 120 were transported to hospital with continuing resuscitation and one survived (0.9%). Survival was higher in patients with an initial cardiac rhythm of ventricular fibrillation (5/14; 35%) compared with other rhythms (10/179; 4%), OR 9.38, 95% CI 2.64-33.2.

CONCLUSIONS

Overall, 7.7% of paediatric patients with out-of-hospital cardiac arrest survive to leave hospital. Increased survival was seen if the initial cardiac rhythm was ventricular fibrillation. Survival was very rare (<1%) unless there was return of spontaneous circulation prior to hospital arrival.

A comparison of Hickman line- and Port-a-Cath-associated complications in patients with solid tumours undergoing chemotherapy

AIMS

To compare the complication rates of Hickman lines and Port-a-Caths in patients undergoing infusional chemotherapy for solid tumours.

MATERIALS AND METHODS

A single institution retrospective analysis comparing complication rates for 30 Hickman lines and 33 Port-a-Caths inserted for chemotherapy in adults with solid tumours was carried out.

RESULTS

Patients were well matched in terms of primary site and chemotherapy regimen. In both cases, over 85% were inserted radiologically under local anaesthetic. The total time in situ for Hickman lines and Port-a-Caths was 3539 days (median 83, range 6-585) and 5783 days (median 158, range 20-456), respectively. The complication rate for Hickman lines was 5.09/1000 catheter days, almost five times that for Port-a-Caths, with 1.04/1000 catheter days, a relative risk of 4.9 (confidence interval: 1.9-15.1, P=0.0003). Most (73%) complications occurred within 4 weeks of insertion. However, some arose much later: the range of time to complication was 1-304 days for Hickman lines and 1-132 days for Port-a-Caths. Infection was the most common complication, accounting for nine of 18 Hickman line complications and five of six Port-a-Cath complications, giving an overall infection rate of 2.54/1000 catheter days and 0.86/1000 catheter days, respectively. Additionally, Hickman lines had a 26% leakage rate or displacement rate, which did not occur at all in the Port-a-Cath group. Complications required the removal of 16 Hickman lines and five Port-a-Caths. The rate of removal was five times higher for Hickman lines (Hickman lines=4.52/1000 catheter days, Port-a-Caths=0.86/1000 catheter days, P=0.0027). Overall, the cost of Port-a-Caths was less than that of Hickman lines.

CONCLUSION

In this study, Port-a-Caths were shown to be both safer and cheaper than Hickman lines for patients requiring infusional chemotherapy.

Tracheal ulceration and obstruction associated with flexible Bivona tracheostomy tubes

An adjustable length tracheostomy tube, Bivona, which assumes a curve on insertion, has a tendency to straighten itself in situ. The straightening force, measured electronically, was maximal (0.21 Newton) when a tube was bent 90 degrees. We observed particular clinical disadvantages of these tubes--that of tracheal ulceration (1 case), distortion of soft tracheal graft tissue (1 case) and airway obstruction when the tip embedded into the tracheal wall (1 case).

Upper airway obstruction caused by ingestion of concentrated acetic acid

We report a case of rapidly progressive severe upper airway obstruction in a small child caused by accidental ingestion of 80% acetic acid. Emergency cricothyrotomy was necessary after both endotracheal intubation and bag-valve-mask ventilation were not possible. Although intubation was eventually achieved, a tracheostomy was necessary. Toxin spilled over the anterior chest and abdomen caused third degree skin burns which required grafting. Mild liver dysfunction was observed. Complete recovery occurred.

Portal vein embolisation prior to hepatic resection for colorectal liver metastases and the effects of periprocedure chemotherapy

Portal vein embolisation (PVE) is an effective method of increasing future liver remnant (FLR) but may stimulate tumour growth. The effect of periprocedure chemotherapy has not been established. 15 consecutive patients underwent PVE prior to hepatic resection for colorectal liver metastases with a FLR <30% of tumour-free liver (TFL). Liver and tumour volumes pre-PVE and 6 weeks post-PVE were calculated by CT or MRI volumetry and correlated with the periprocedure chemotherapy regimen. PVE increased the FLR from 18+/-5% of TFL to 27+/-8% post-PVE (p<0.01). Post-PVE chemotherapy did not prevent hypertrophy of the FLR but the volume increase with chemotherapy (median 89 ml, range 7-149 ml) was significantly reduced (median 135 ml, range 110-254 ml without chemotherapy) (p = 0.016). Tumour volume (TV) decreased in those receiving post-PVE chemotherapy (median TV decrease 8 ml, range -77 ml to +450 ml) and increased without chemotherapy (median TV increase 39 ml, range -58 ml to +239 ml). Of the 15 patients, eight underwent resection; four were not resected due to disease progression and three due to insufficient hypertrophy of the FLR. PVE increased the FLR by an average of 9% allowing resection in 50% of patients. Periprocedure chemotherapy did not prevent but did reduce hypertrophy. A trend towards tumour regression was observed.

Methylene blue for diagnosis of displaced atrial lines

Methylene blue (aniline violet, tetra-methylthionine chloride) has several important uses in clinical medicine, including diagnosis of displaced central lines. After cardiac surgery, three infants with suspected displacement of direct atrial lines were given methylene blue. After injection of the dye into the atrial lines, bluish discolouration was identified in their chest drainage. Use of methylene blue in small amounts appears to be a safe and effective way of diagnosing extravasation of fluid from displaced central lines.

Reduction of paediatric in-patient cardiac arrest and death with a medical emergency team: preliminary results

AIMS

To determine the impact of a paediatric medical emergency team (MET) on cardiac arrest, mortality, and unplanned admission to intensive care in a paediatric tertiary care hospital.

METHODS

Comparison of the retrospective incidence of cardiac arrest and death during 41 months before introduction of a MET service with the prospective incidence of these events during 12 months after its introduction. Comparison of transgression of MET call criteria in patients who arrested and died before and after introduction of MET.

RESULTS

Cardiac arrest decreased from 20 among 104 780 admissions (0.19/1000) to 4 among 35 892 admissions (0.11/1000) (risk ratio 1.71, 95% CI 0.59 to 5.01), while death decreased from 13 (0.12/1000) to 2 (0.06/1000) during these periods (risk ratio 2.22, 95% CI 0.50 to 9.87). Unplanned admissions to intensive care increased from 20 (SD 6) to 24 (SD 9) per month. The incidence of transgression of MET call criteria in patients who arrested decreased from 17 to 0 (risk difference 0.16/1000, 95% CI 0.09 to 0.24), and in those who died, decreased from 12 to 0 (risk difference 0.11/1000, 95% CI 0.05 to 0.18) after introduction of MET.

CONCLUSIONS

Introduction of a medical emergency team service was coincident with a reduction of cardiac arrest and mortality and a slight increase in admissions to intensive care.

Bleeding ectopic varices--treatment with transjugular intrahepatic porto-systemic shunt (TIPS) and embolisation

BACKGROUND/AIMS

Bleeding ectopic varices due to cirrhosis can be difficult to manage. We report our experience of uncontrolled bleeding from ectopic varices treated with transjugular intrahepatic porto-systemic shunt (TIPS).

METHODS

We selected the 21 cirrhotics who underwent TIPS for bleeding ectopic varices from our database: Child-Pugh grade A (2), B (11) and C (8). Site of bleeding was rectal (11), colonic (2), ileal 1, jejunal 1, duodenal 1, and stomal (5).

RESULTS

TIPS was performed successfully in 19/21 (90%) patients. All except 1 had either a reduction in portosystemic pressure gradient < or = 12 mmHg (n=12) or reduction by 25-50% of baseline (n=6). TIPS alone was used in 12/19: 7 of these 12 had no further bleeding; 5 (42%) rebled within 48 h, and had embolisation, 4 without further bleeding. In 7 of 19, TIPS and embolisation were performed together: 2 patients (28%) rebled; further embolisation stopped the bleeding.

CONCLUSIONS

Ectopic varices do rebleed despite a reduction of porto-systemic pressure gradient < or = 12 mmHg or by 25-50% of baseline, following TIPS. Embolisation stopped bleeding in all but 1 patient. We recommend performing embolisation at the time of the initial TIPS to control bleeding from ectopic varices.

Cardiovascular, haematological and neurological effects of the venom of the Papua New Guinean small-eyed snake (Micropechis ikaheka) and their neutralisation with CSL polyvalent and black snake antivenoms

Cardiovascular and haematological effects of venom of the small-eyed Snake (Micropechis ikaheka) were examined in ventilated anaesthetised piglets. Neurotoxic effects were examined in chick biventer cervicis nerve-muscle preparations. Immunoreactivity of venom was tested against the monovalent antivenom components in a CSL Ltd Venom Detection Kit. Neutralisation was tested in vivo and in vitro with CSL Ltd polyvalent snake and Black Snake (Pseudechis australis) antivenoms. Venom in 0.1% bovine serum albumin in saline was infused into piglets in doses 1-2000 microg/kg. Pulmonary hypertension (P= 0.0007) and depression of cardiac output (P= 0.002) were observed up to 3 h after 150-160 microg/kg. The concentration of plasma free-haemoglobin increased more than 50-fold, indicating haemolysis. Neither coagulopathy nor thrombocytopenia occurred. Creatine phosphokinase and serum potassium levels did not increase suggesting absence of acute rhabdomyolysis. The venom caused post-synaptic neurotoxicty. Immunoreactivity of venom with Black Snake antivenom was observed at very high venom concentrations. Cardiovascular effects were absent and haemolysis was less after venom was pre-incubated at 37 degrees C for 30 min with polyvalent antivenom. Neutralisation by Black Snake antivenom was less effective. The neurotoxicity was neutralised by polyvalent or Black Snake antivenoms. Human envenomation may be treated with CSL Ltd polyvalent snake antivenom.

TIPS for acute and chronic Budd-Chiari syndrome: a single-centre experience

BACKGROUND/AIMS

Transjugular intrahepatic portosystemic shunt (TIPS) is a technically challenging but feasible treatment for Budd-Chiari syndrome (BCS). However, information about the outcome, particularly in patients with liver failure, is scarce. We report our experience of TIPS for BCS.

METHODS

Fifteen patients with BCS underwent TIPS. Eight had hepatic failure and seven underwent TIPS for BCS uncontrolled by medical treatment.

RESULTS

Fourteen out of 15 had successful TIPS placement. Out of the eight hepatic failure patients, four died soon after TIPS: one liver rupture, one portal vein rupture, one liver failure and one pulmonary oedema. Another patient had a significant intrahepatic haematoma, which resolved with conservative management. TIPS was successfully placed in all of the seven patients with chronic BCS, in whom there was an average follow-up of 20 months. Ascites resolved and liver function improved in all. One patient died after 18 months from the original hepatic metastatic disease. Four patients have had evidence of TIPS dysfunction requiring three balloon dilatations and one restenting. No patient has required liver transplantation.

CONCLUSIONS

TIPS should be the first line treatment for BCS uncontrolled by medical therapy. However, mortality in BCS with hepatic failure is high and liver transplantation could be a better option.

Focal nodular hyperplasia-like areas in cirrhosis

AIMS

Focal nodular hyperplasia-like lesions have rarely been described in cirrhotic livers. We describe five cases of such lesions.

METHODS AND RESULTS

Between 1998 and 2001, 146 liver transplants were performed at the Royal Free Hospital for cirrhosis of the liver. Nodular lesions identified in the livers removed at transplantation were defined histologically according to the International Working Party classification (Hepatology 1995; 22; 983). They were present in 63 of these livers, as follows: 36 dysplastic nodules, 121 macroregenerative nodules, and 71 hepatocellular carcinomas. In five patients, an additional 12 nodules (size range 4-23 mm, median 10.5 mm) showed histological features suggestive of focal nodular hyperplasia including mildly inflamed vascular fibrous septa, and ductular proliferation. Pre-transplantation imaging showed features suspicious for hepatocellular carcinoma, in three of these lesions (12, 23 and 23 mm diameter) from two different patients. These lesions were histologically indistinguishable from focal nodular hyperplasia occurring in non-cirrhotic livers, with fibrous scars and septa which contained vascular and ductular structures.

CONCLUSIONS

It is important to recognize that these lesions may occur in the context of cirrhosis and that they should be considered in the differential diagnosis with hepatocellular carcinoma, dysplastic nodules and macroregenerative nodules.

Incidence of alveolar capillary dysplasia in severe idiopathic persistent pulmonary hypertension of the newborn

OBJECTIVE

To determine the incidence and outcome and to review the management of alveolar capillary dysplasia (ACD) among newborns with severe idiopathic persistent pulmonary hypertension (PPHN).

METHODS

A retrospective review of medical records of infants admitted to a paediatric intensive care unit from 1982 to 2000 with a diagnosis of severe PPHN, and re-examination of lung histological sections was carried out.

RESULTS

Thirteen new-born infants with pulmonary hypertension not associated with any known cause were identified. All were treated with conventional mechanical ventilation or high-frequency oscillatory ventilation with high inspired-oxygen and non-specific pulmonary vasodilators. Nine infants were also treated with inhaled nitric oxide therapy and eight with extracorporeal membrane oxygenation (ECMO). Seven infants died and six survived. At autopsies, the histological features of ACD were seen in the six who had died in the newborn period. All these had been treated with ECMO. In two of these six infants, lung biopsies had been performed showing similar features, suggesting the possibility of diagnosis during life. In the remaining infant, who died at 3 months of age, there was only marked hypertrophy of the muscle coat in the small pulmonary arteries.

CONCLUSIONS

Alveolar capillary dysplasia is probably not as rare a condition as previously suggested in sporadic case reports from literature on the subject. It should be entertained as a cause of otherwise severe idiopathic PPHN of the newborn, particularly if ECMO is required. Diagnosis during life is possible by lung biopsy. It is uncertain if survival occurs with milder forms of the condition.

Use of stents in the palliative treatment of malignant gastric outlet and duodenal obstruction

AIM

To evaluate the efficacy of stenting in the palliation of malignant duodenal and gastric outlet obstruction.

MATERIALS AND METHODS

We retrospectively reviewed our series of patients who underwent stenting for malignant upper gastrointestinal obstruction between March 1998 and December 1999. From January 2000 data have been acquired prospectively. Our series comprises 21 stents successfully deployed in 15 patients.

RESULTS

The technical and clinical success was 93% (14/15 patients). One patient required endoscopic negotiation of recurrent gastric carcinoma at the gastrojejunostomy site after failure to cross the lesion fluroscopically. Two patients required re-intervention 2 and 5 weeks after initial stent placement, for migration and ingrowth respectively. Eighteen stents were placed transorally, two stents transhepatically and one via a transgastric approach. Early complications (pain < 3 days) occurred in two patients (13%) and late complications (ingrowth, overgrowth and migration) occurred in three patients (20%). The median survival was 2.4 months (range 2-4 months).

CONCLUSION

Stenting provides a less invasive palliative option than surgery with the advantage of lower morbidity and complication rates. It has the advantage of high technical and clinical success rates facilitated by alternative routes of access into the upper gastrointestinal tract via transgastric and transhepatic routes in addition to the traditional peroral route.

Radiological palliation of malignant colonic obstruction

PURPOSE

To evaluate the efficacy of colorectal stenting in the palliation of irresectable malignant colonic obstruction.

MATERIALS AND METHODS

Fifteen patients underwent colorectal stenting for irresectable colonic malignancy. Sixteen stents were placed successfully in 13 patients. Two stent insertions, one a proximal transverse colon lesion, were unsuccessful. Twelve patients (80%) had clinical or radiological features of imminent obstruction. Three patients were completely obstructed. Eighty-six percent of lesions were within the rectosigmoid colon.

RESULTS

Technical and clinical success was 88%. Early, minor complications occurred in two patients (13%). Late complications included migration (13%) and ingrowth (19%). The median survival was 2 months (0.5-12 months).

CONCLUSION

Stenting should be considered as definitive treatment in the context of an inoperable malignant stricture of the colon. It has low morbidity and a high technical and clinical success rate and avoids emergency defunctioning surgery in high-risk patients.

An advisory statement from the Pediatric Working Group of the International Liaison Committee on Resuscitation

The International Liaison Committee on Resuscitation (ILCOR), with representation from North America, Europe, Australia, New Zealand, Africa, and South America, was formed in 1992 to provide a forum for liaison between resuscitation organizations in the developed world. This consensus document on resuscitation extends previously published ILCOR advisory statements on resuscitation to address the unique and changing physiology of the newly born infant within the first few hours after birth and the techniques for providing advanced life support. After careful review of the international resuscitation literature and after discussion of key and controversial issues, consensus was reached on almost all aspects of neonatal resuscitation, and areas of controversy and high priority for additional research were delineated. Consensus on resuscitation for the newly born infant included the following principles: Personnel trained in the basic skills of resuscitation should be in attendance at every delivery. A minority (fewer than 10%) of newly born infants require active resuscitative interventions to establish a vigorous cry and regular respirations, maintain a heart rate > 100 beats per minute (bpm), and maintain good color and tone. When meconium is present in the amniotic fluid, it should be suctioned from the hypopharynx on delivery of the head. If the meconium-stained newly born infant has absent or depressed respirations, heart rate, or muscle tone, residual meconium should be suctioned from the trachea. Attention to ventilation should be of primary concern. Assisted ventilation with attention to oxygen delivery, inspiratory time, and effectiveness judged by chest rise should be provided if stimulation does not achieve prompt onset of spontaneous respirations and/or the heart rate is < 100 bpm. Chest compressions should be provided if the heart rate is absent or remains < 60 bpm despite adequate assisted ventilation for 30 seconds. Chest compressions should be coordinated with ventilations at a ratio of 3:1 and a rate of 120 "events" per minute to achieve approximately 90 compressions and 30 rescue breaths per minute. Epinephrine should be administered intravenously or intratracheally if the heart rate remains < 60 bpm despite 30 seconds of effective assisted ventilation and chest compression circulation. Common or controversial medications (epineprine, volume expansion, naloxone, bicarbonate), special resuscitation circumstances affecting care of the newly born, continuing care of the newly born after resuscitation, and ethical considerations for initiation and discontinuation of resuscitation are discussed. There was agreement that insufficient data exist to recommend changes to current guidelines regarding the use of 21% versus 100% oxygen, neuroprotective interventions such as cerebral hypothermia, use of a laryngeal mask versus endotracheal tube, and use of high-dose epinephrine. Areas of controversy are identified, as is the need for additional research to improve the scientific justification of each component of current and future resuscitation guidelines.

An evaluation of nitric oxide and nitrogen dioxide absorbers and filters

The absorbance of NO (5-90 ppm) and NO2 (0.5-4 ppm) by a number of absorbers and filters was assessed via bench testing. All absorbers (Sodasorb, Purafil CP, Purafil Select, Sofnolime, Sofnofil and 50/50 mix of Sofnolime/Sofnofil) except Sodasorb absorbed NO almost completely. Only Sofnolime absorbed NO2 completely while Sodasorb and the Sofnolime/Sofnofil 50/50 mix had absorbances between 47% and 90%. The absorbance of four filters (ILF100, ILF150, ILF200 and HgCONO) as well as Sofnolime and the Sofnolime/Sofnofil 50/50 mix was tested in the expiratory port of a Servo 900C ventilator All absorbers and filters produced a change in ventilator pressures. The HgCONO filter Sofnolime and the Sofnolime/Sofnofil 50/50 mix all absorbed NO. At 80 ppm NO, the HgCONO filter had 100% absorbance for four hours while Sofnolime's absorbance was significantly reduced after one hour. All filters and absorbers tested on the ventilator except the Sofnolime/Sofnofil 50/50 mix and the ILF150 filter absorbed NO2 completely for a period ranging from 90 minutes to four hours. We recommend the HgCONO filter and Sofnolime to absorb both NO and NO2. If absorption of NO2 only is required we recommend the HgCONO, ILF100 or ILF200 filters or the Sofnolime absorber.

Childhood poisoning: access and prevention

OBJECTIVES

To investigate the circumstances and means of access to six poisoning agents by children under 5 years of age and to make recommendations for countermeasures and strategies for implementation.

METHODOLOGY

A case series study of access to six poisoning agents was conducted. Cases were identified prospectively through a poisons information centre and hospital emergency departments. Interviews were conducted with 523 parents and caregivers using a structured questionnaire.

RESULTS

The majority of children (94.1%) accessed the agent in their own home or another home and, in 38% of cases (excluding mistakes in administration), the parent or caregiver was present in the immediate area at the time of the incident. In cases in which the child was alone in the room, caregivers were frequently involved in household duties (51%), with only 10% undertaking leisure activities and 8% on the telephone. The span of unsupervised time reported was 5 min or less in 79.5% of these cases. The means of access was generally during periods of use of the agent (75.3%), including just purchased, rather than when agents were in their usual storage place.

CONCLUSIONS

There is little scope for improved supervision as a major intervention. Design and regulatory changes such as local safe storage for bench tops and while travelling, improved labelling and packaging, improved child-resistant packaging and its more general application are required. These and agent-specific interventions, including child-resistant bait stations for rodenticides and well covers for vaporizers, are more likely to prevent poisoning. The recent identification of childhood poisoning prevention as a national priority may lead to coordinated action to implement these and other preventive measures.

Successful recanalization of portal vein thrombosis before liver transplantation using transjugular intrahepatic portosystemic shunt

A frequent complication in patients with end-stage liver disease is portal vein thrombosis (PVT). Although PVT is not considered an absolute contraindication to orthotopic liver transplantation (OLT), more complex surgery is required and patients have more postoperative complications and greater mortality rates. We describe 2 patients who experienced complete PVT either while waiting for liver transplantation or during the workup, resulting in acute deterioration of liver function. Recanalization of the portal vein was successfully performed in both patients using transjugular intrahepatic portosystemic stent shunt (TIPS), and patency was maintained by the addition of anticoagulation therapy. They subsequently underwent successful OLTs and remain well. In conclusion, we believe that TIPS placement can be performed safely in patients with recent PVT, ensuring the patency of the portal vein until OLT.

A randomized trial of very early decompressive craniectomy in children with traumatic brain injury and sustained intracranial hypertension

OBJECT

The object of our study was to determine, in children with traumatic brain injury and sustained intracranial hypertension, whether very early decompressive craniectomy improves control of intracranial hypertension and longterm function and quality of life.

METHODS

All children were managed from admission onward according to a standardized protocol for head injury management. Children with raised intracranial pressure (ICP) were randomized to standardized management alone or standardized management plus cerebral decompression. A decompressive bitemporal craniectomy was performed at a median of 19.2 h (range 7.3-29.3 h) from the time of injury. ICP was recorded hourly via an intraventricular catheter. Compared with the ICP before randomization, the mean ICP was 3.69 mmHg lower in the 48 h after randomization in the control group, and 8.98 mmHg lower in the 48 hours after craniectomy in the decompression group (P=0.057). Outcome was assessed 6 months after injury using a modification of the Glasgow Outcome Score (GOS) and the Health State Utility Index (Mark 1). Two (14%) of the 14 children in the control group were normal or had a mild disability after 6 months, compared with 7 (54%) of the 13 children in the decompression group. Our conclusion was that when children with traumatic brain injury and sustained intracranial hypertension are treated with a combination of very early decompressive craniectomy and conventional medical management, it is more likely that ICP will be reduced, fewer episodes of intracranial hypertension will occur, and functional outcome and quality of life may be better than in children treated with medical management alone (P=0.046; owing to multiple significance testing P <0.0221 is required for statistical significance). This pilot study suggests that very early decompressive craniectomy may be indicated in the treatment of traumatic brain injury.

Carbon-dioxide portography: an expanding role?

We describe a new and inexpensive technique of imaging the portal vein in patients with liver disease by use of carbon dioxide.

Liver transplantation complicated by embedded transjugular intrahepatic portosystemic shunt: a new method for portal anastomosis- a surgical salvage procedure

A transjugular intrahepatic portosystemic shunt (TIPS) is an increasingly used method of treating variceal bleeding from portal hypertension. Many patients are subsequently listed for transplantation, which may be complicated by malposition of the inferior end of the TIPS stent. This report details such a case and offers a surgical technique to salvage this situation.

An analysis of the efficacy of bag-valve-mask ventilation and chest compression during different compression-ventilation ratios in manikin-simulated paediatric resuscitation

The ideal chest compression and ventilation ratio for children during performance of cardiopulmonary resuscitation (CPR) has not been determined. The efficacy of chest compression and ventilation during compression ventilation ratios of 5:1, 10:2 and 15:2 was examined. Eighteen nurses, working in pairs, were instructed to provide chest compression and bag-valve-mask ventilation for 1 min with each ratio in random on a child-sized manikin. The subjects had been previously taught paediatric CPR within the last 3 or 5 months. The efficacy of ventilation was assessed by measurement of the expired tidal volume and the number of breaths provided. The rate of chest compression was guided by a metronome set at 100/min. The efficacy of chest compressions was assessed by measurement of the rate and depth of compression. There was no significant difference in the mean tidal volume or the percentage of effective chest compressions delivered for each compression-ventilation ratio. The number of breaths delivered was greatest with the ratio of 5:1. The percentage of effective chest compressions was equal with all three methods but the number of effective chest compressions was greatest with a ratio of 5:1. This study supports the use of a compression-ventilation ratio of 5:1 during two-rescuer paediatric cardiopulmonary resuscitation.

Systemic vasculitis with multiple aneurysms complicating systemic lupus erythematosus

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Transjugular liver biopsy in the 1990s: a 2-year audit

BACKGROUND

In view of the changing nature of transjugular liver biopsy, we performed an audit of the safety, adequacy and clinical impact of such biopsies in our centre over a 2-year period from 1995 to 1997.

METHODS

One hundred and fifty-seven transjugular biopsies were carried out in 145 patients, with prothrombin time >5 s over control and/or platelet count <50 x 10(9)/L and/or gross ascites.

RESULTS

Major complications were two (1.3%) capsular perforations, which were easily plugged with coils without sequelae. Biopsy sample was adequate for histological diagnosis in 90%, inadequate in 6% and technically unsuccessful in 4% of cases. Mean biopsy size was 14.8+/-7.7 (1-51) mm. Adequacy did not differ between cases with and without cirrhosis. Transjugular biopsy had a clinical impact (specific diagnosis or influence on patient's management) in 50% of acute liver disease, 62% of chronic liver disease and 87% of transplant patients (P<0.001). In chronic liver disease, it had a significantly greater clinical impact in cases trying to establish the stage rather than diagnosis (84% vs. 35%, P<0.001).

CONCLUSIONS

Transjugular liver biopsy is a safe procedure for high-risk patients providing an adequate liver sample even in cirrhosis. It has a clinical impact in more than 80% of transplant patients and for staging chronic liver disease, but in only 50% (acute) or 35% (chronic) of liver disease when a diagnosis is sought.

An advisory statement from the Pediatric Working Group of the International Liaison Committee on Resuscitation

The International Liaison Committee on Resuscitation (ILCOR), with representation from North America, Europe, Australia, New Zealand, Africa, and South America, was formed in 1992 to provide a forum for liaison between resuscitation organizations in the developed world. This consensus document on resuscitation extends previously published ILCOR advisory statements on resuscitation to address the unique and changing physiology of the newly born infant within the first few hours after birth and the techniques for providing advanced life support. After careful review of the international resuscitation literature and after discussion of key and controversial issues, consensus was reached on almost all aspects of neonatal resuscitation, and areas of controversy and high priority for additional research were delineated. Consensus on resuscitation for the newly born infant included the following principles: Common or controversial medications (epinephrine, volume expansion, naloxone, bicarbonate), special resuscitation circumstances affecting care of the newly born, continuing care of the newly born after resuscitation, and ethical considerations for initiation and discontinuation of resuscitation are discussed. There was agreement that insufficient data exist to recommend changes to current guidelines regarding the use of 21% versus 100% oxygen, neuroprotective interventions such as cerebral hypothermia, use of a laryngeal mask versus endotracheal tube, and use of high-dose epinephrine. Areas of controversy are identified, as is the need for additional research to improve the scientific justification of each component of current and future resuscitation guidelines.

Resuscitation of the newly born infant: an advisory statement from the Pediatric Working Group of the International Liaison Committee on Resuscitation

The International Liaison Committee on Resuscitation (ILCOR), with representation from North America, Europe, Australia, New Zealand, Africa, and South America, was formed in 1992 to provide a forum for liaison between resuscitation organizations in the developed world. This consensus document on resuscitation extends previously published ILCOR advisory statements on resuscitation to address the unique and changing physiology of the newly born infant within the first few hours following birth and the techniques for providing advanced life support.

Unintentional poisoning hospitalisations among young children in Victoria

OBJECTIVES

To describe the epidemiology of unintentional childhood poisoning hospitalisation in Victoria, Australia, in order to monitor trends and identify areas for research and prevention.

METHODS

For children under 5 years, all Victorian public hospital admissions, July 1987 to June 1995, due to unintentional poisoning by drugs, medicines, and other substances were analysed. Similar cases were also extracted from the database of the Royal Children's Hospital intensive care unit, Melbourne for the years 1979-91. Log linear regression modelling was used for trend analyses.

RESULTS

The annual average childhood unintentional poisoning rate was 210.7 per 100,000. Annual rates for males consistently exceeded those for females. The most common agents were those acting on the respiratory system and on smooth and skeletal muscles (muscle relaxants, cough and cold medicines, antiasthmatics), aromatic analgesics (paracetamol), and systemic agents (including antihistamines). Further investigation is justified for cardiac agents, some respiratory agents, and asthma medications.

CONCLUSIONS

Childhood poisoning hospitalisation rates have not decreased in Victoria over recent years. A focused, agent specific approach, as well as a series of generic measures for the prevention of poisoning to children under 5 is advocated. The ongoing surveillance, collection and analysis of data, in addition to research on specific poisoning agents are essential components of any prevention strategy.

Resuscitation of the newly born infant: an advisory statement from the Pediatric Working Group of the International Liaison Committee on Resuscitation

The International Liaison Committee on Resuscitation (ILCOR), with representation from North America, Europe, Australia, New Zealand, Africa, and South America, was formed in 1992 to provide a forum for liaison between resuscitation organizations in the developed world. This consensus document on resuscitation extends previously published ILCOR advisory statements on resuscitation to address the unique and changing physiology of the newly born infant within the first few hours following birth and the techniques for providing advanced life support. After careful review of the international resuscitation literature and after discussion of key and controversial issues, consensus was reached on almost all aspects of neonatal resuscitation, and areas of controversy and high priority for additional research were delineated. Consensus on resuscitation for the newly. born infant included the following principles. (i) Personnel trained in the basic skills of resuscitation should be in attendance at every delivery. A minority (fewer than 10%) of newly born infants require active resuscitative interventions to establish a vigorous cry and regular respirations, maintain a heart rate greater than 100 beats per minute (bpm), and maintain good color and tone. (ii) When meconium is present in the amniotic fluid, it should be suctioned from the hypopharynx on delivery of the head. If the meconium-stained newly born infant has absent or depressed respirations, heart rate, or muscle tone, residual meconium should be suctioned from the trachea. (ii) Attention to ventilation should be of primary concern. Assisted ventilation with attention to oxygen delivery, inspiratory time, and effectiveness judged by chest rise should be provided if stimulation does not achieve prompt onset of spontaneous respirations and/or the heart rate is less than 100 bpm. (iv) Chest compressions should be provided if the heart rate is absent or remains less than 60 bpm despite adequate assisted ventilation for 30 s. Chest compressions should be coordinated with ventilations at a ratio of 3:1 and a rate of 120 'events' per minute to achieve approximately 90 compressions and 30 rescue breaths per minute. (v) Epinephrine should be administered intravenously or intratracheally if the heart rate remains less than 60 bpm despite 30 s of effective assisted ventilation and chest compression circulation. Common or controversial medications (epinephrine, volume expansion, naloxone, bicarbonate), special resuscitation circumstances affecting care of the newly born, continuing care of the newly born after resuscitation, and ethical considerations for initiation and discontinuation of resuscitation are discussed. There was agreement that insufficient data exist to recommend changes to current guidelines regarding the use of 21% versus 100% oxygen, neuroprotective interventions such as cerebral hypothermia, use of a laryngeal mask versus endotracheal tube, and use of high-dose epinephrine. Areas of controversy are identified, as is the need for additional research to improve the scientific justification of each component of current and future resuscitation guidelines.

Ultrasound screening for hepatocellular carcinoma (HCC) in cirrhosis: the evidence for an established clinical practice

Improvement in our current knowledge of epidemiology, natural history and treatment modalities form the background to generalize the use of ultrasound screening in cirrhosis. The cumulative probability of developing cancer is extremely high in cirrhotics and allows to focus screening programs on a well defined risk group thus maximizing cost-effectiveness. This review article highlights scientific evidences in favour of a generalized practice of US screening.