Comparison of nasal prongs with nasal catheters in the delivery of oxygen to children with hypoxia

Efficient, inexpensive, and safe methods of oxygen delivery are needed for children with severe pneumonia in developing countries. The objective of this study was to estimate the frequency of complications when nasal catheters or nasal prongs are used to delivery oxygen. Ninety-nine children between 2 weeks and 5 years of age with hypoxia were randomized to receive oxygen via nasal catheter (49 children) or nasal prongs (50 children). There was no difference in the incidence of hypoxaemic episodes or in the oxygen flow rates between the two groups. Mucus production was more of a problem in the catheter group. Nasal blockage, intolerance to the method of administration, and nursing effort were generally higher amongst the catheter group, but these differences were not significant, except for nursing effort, when all age groups were analysed together.     

Use of a modified non-rebreathing mask during upper intestinal endoscopy

BACKGROUND AND STUDY AIMS: Recently, attention has been drawn to the significant occurrence of respiratory and other complications during upper intestinal endoscopy. This prospective study was designed to compare the incidence and severity of oxygen desaturation when two different methods of oxygen delivery were used during elective oesophagogastroduodenoscopy. PATIENTS AND METHODS: After local medical ethics committee approval and written informed consent, one hundred patients undergoing elective oesophagogastroduodenoscopy were randomly allocated to receive supplemental oxygen at either four litres per minute via nasal specular or ten litres per minute through a specially modified non-rebreathing mask. Oxygen saturations during endoscopy facilitated by midazolam sedation were recorded, and non-parametric tests were used to compare the oxygen saturations in the two groups. RESULTS: The mean oxygen saturations were significantly better during the procedure for American Society of Anesthesiology (ASA) grade 2 and 3 patients who received oxygen with the modified mask than for those who received oxygen via nasal specular (98.6% vs. 97.0%, P = 0.004 for ASA grade 2 and 98.4% vs. 95.5, P = 0.006 for ASA grade 3). CONCLUSIONS: For ASA grade 2 and 3 patients, the modified non-rebreathing mask significantly improves oxygen saturations during upper intestinal endoscopy. This technique should be more widely used for patients at moderate and high risk.     

Administration of nitrous oxide in normal subjects. Evaluation of systems of gas delivery for their clinical use and hemodynamic effects

Nitrous oxide (concentrations of 30 to 50%) was administered to 22 healthy volunteer subjects via nasal prongs, rebreathing mask, and an airlines mask to assess the efficiency of systems of delivery and the hemodynamic effects. The end-expired concentration of nitrous oxide, expressed as a percentage of the inspired concentration of nitrous oxide, was 19% for nasal prongs, 34% for the rebreathing mask, and 95% for the airlines mask (most accurate delivery). The pulse rate fell from a mean of 79+/-3 beats per minute to 67+/-2 with nasal prongs, to 64+/-2 with the rebreathing mask, and to 64+/-2 with the airlines mask. Both systolic and diastolic pressures fell from means of 122+/-4 and 74+/-2 mm Hg, respectively, to 98+/-3 mm Hg and 64+/-2 mm Hg, respectively, with the airlines apparatus. The fall in systolic blood pressure (slope, -0.79) exceeded that in the diastolic (slope, -0.35). In additional eight normal subjects, administration of 30% nitrous oxide via airlines mask produced identical changes in blood pressure and pulse rate, but there was no effect from 30 minutes of administration of 30% nitrous oxide on the end-systolic volume index, cardiac index, ejection fraction, normalized wall velocity determined echocardiographically, ejection time, or the ratio of preejection period to ejection time.     

A comparison of the nasal mask and the nasopharyngeal airway in paediatric chair dental anaesthesia

This study compared the quality of anaesthesia and surgical access afforded by two techniques for the administration of anaesthesia during paediatric chair dental procedures. A total of 50 ASA 1 paediatric day case patients were randomly assigned to receive anaesthesia through either the traditional Goldman nasal mask or through a nasopharyngeal airway. Patients in the nasal mask group were judged to have significantly worse airway patency (p = 0.0001) and significantly more episodes of airway obstruction (14 vs. 4; p = 0.0032) than those in the nasopharyngeal airway group. Anaesthetic, surgical and oxygen saturation data did not differ significantly between the two groups. Operating conditions were universally graded as excellent in the nasopharyngeal airway group, while those in the nasal mask group were graded as excellent/good in only 79% of cases (p < 0.0001). These results suggest that better quality anaesthesia and operating conditions can be achieved by using a nasopharyngeal airway rather than the traditional nasal mask for the administration of anaesthesia to paediatric chair dental patients.     

Mechanism of mosaic attenuation of the lungs on computed tomography in induced bronchospasm

The purpose of this study was to investigate whether hypoxic pulmonary vasoconstriction is the major determinant of the computed tomography (CT) pattern of mosaic attenuation in asthmatic patients with induced bronchoconstriction. Thin-section CT was performed at suspended full inspiration immediately and 30 min after methacholine bronchoprovocation in 22 asthmatic subjects, who were randomly assigned to breathe room air (group A, n = 8), oxygen via nasal prongs at 5 l/min (group B, n = 8), and oxygen via face mask at 12 l/min (group C, n = 6). CT changes were quantified in terms of global lung density and density in hypodense and hyperdense areas. Lung parenchymal density increases were greatest in group C and greater in group B than in group A, globally (P = 0.03) and in hypodense regions (P = 0.01). On bivariate analysis, the only change in cross-sectional area was related to change in global density. In hypodense regions, density change was related both to reduction in cross-sectional area (P < 0.0005) and to oxygen administration (P = 0.01). After correction for changes in global lung density, only oxygen was independently related to density increase in hypodense areas (P = 0.02). In induced bronchoconstriction, the CT appearance of mosaic attenuation can be largely ascribed to hypoxic vasoconstriction rather than to changes in lung inflation.     

Stomach rupture after nasal oxygen therapy

A 69-year-old male developed a spontaneous rupture of the normal stomach during oxygen administration via a nasopharyngeal catheter. The clinical picture and treatment is discussed.     

Comparison of clarithromycin suspension and amoxycillin syrup for the treatment of children with pharyngitis and/or tonsillitis

A community-based logitudinal study conducted in Matlab, a rural area in Bangladesh, investigated acute respiratory infections (ARI) among children. A cohort of 696 children under 5 years of age was followed for 1 year yielding 183,865 child-days of observation. Trained field workers visited the study children every fourth day. Data on symptoms suggesting ARI, such as fever, cough, and nasal discharge, were collected for the preceding 3 days by recall. To determine the type and severity of ARI, the field workers conducted physical examinations (temperature, rate of respiration, and chest indrawing) of children reporting cough and/or fever. The overall incidence of ARI was 5.5 episodes per child-year observed; the prevalence was 35.4 per hundred days observed. Most of the episodes (96 per cent) were upper respiratory infections (URI). The incidence of acute lower respiratory infections (ALRI) was 0.23 per child per year. The incidence of URI was highest in 18-23-month-old children, followed by infants 6-11 months old. The highest incidence of ALRI was observed in 0-5-month-old infants followed by 12-17-month-old children. Among 559 children who were followed for 6 months or longer, about 9 per cent did not suffer any URI episode and about 16 per cent suffered one or more ALRI episodes. About 46 per cent of URI and 65 per cent of ALRI episodes lasted 15 days or more. The incidence rates of URI were higher during the monsoon and pre-winter periods, and that of ALRI at the end of the monsoon and during the pre-winter periods. Sociodemographic variables were not associated with the incidence of URI or ALRI. The study documents ARI to be a major cause of morbidity among rural Bangladeshi children.     

Early treatment with nasal continuous positive airway pressure and "minimal handling". Early and late prognosis in children with birth weight under 1,501 g

During 1988 and 1989 a regional cohort of 81 infants with birth weights of less than 1501 g were treated with oxygen (n = 11), early continuous positive airway pressure (CPAP) (n = 68) or mechanical ventilation from birth (n = 2). We used an easily applicable lightweight CPAP system with nasal prongs and a gas jet supplemented with ventilator treatment if necessary, but with conservative criteria for ventilator treatment with tolerance of high PCO2. A total of 65 infants (80%) survived to discharge, 61 of whom were supported solely with CPAP or oxygen. Nineteen infants (26%) developed periventricular-intraventricular haemorrhage, but only four survivors (6%) developed prognostically significant bleedings of grade 2-4. No survivors had bronchopulmonary dysplasia. Follow-up at 1.5-5 years of age revealed definite disabilities in seven (11%). The results suggest that treatment by early CPAP with nasal prongs with tolerance of high PCO2 may be effective and lenient in most infants of more than 25 weeks' gestation.     

Clinical evaluation of a test for immediate and quantitative determination of urinary albumin-to-creatinine ratio. A brief report

A technique is proposed for positioning the nasal oxygen cannula during facial surgery performed under local anesthesia and intravenous sedation. By placing the nasal prongs in the nostrils, and passing the tubing along the alar grooves, nasal dorsum, and forehead, the surgeon has full access to the preauricular areas, temporal regions, cheeks, nasolabial folds, and oral commissures. This method is easy to perform, provides secure positioning of the nasal oxygen, and allows access to areas of the face not possible with conventional placement of the oxygen cannula.     

Prognostic value of thoracic recurrent nerve nodal involvement in esophageal squamous cell carcinoma

The authors compared the acceptance and efficacy of rectal and nasal administration of midazolam (MDZ) for premedication. Ninety-five ASA I and II paediatric patients (8 months to 12 years) scheduled for elective surgery were randomly allocated to two groups. Group R received 0.3 mg kg-1 of rectal midazolam (in 5 mL saline). Group N received 0.2 mg kg-1 of nasal midazolam (5 mg ml-1). Both groups were divided in two subgroups according to age (group RA (< or = 6 years, n = 33), group RB (> 6 years, n = 18), group NA (< or = 6 years, n = 28), group NB (> 6 years, n = 16)). At the time of premedication, tolerance to the administration was confirmed. Twenty min after rectal or 10 min after nasal administration the quality of sedation was recorded. The nasal midazolam, in commonly used dosages, induced a sedation similar to that following rectal administration with a shorter delay of onset. Nasal administration was more often painful than rectal administration. Swallowing (nasal midazolam) and concerns about modesty (rectal midazolam) were more frequent in older children. Because of its poor tolerance, nasal premedication should be reversed for cases where there is no alternative. Rectal premedication should be avoided in older children.     

Respiratory syncytial virus infection in tropical and developing countries

Little is known about the epidemiology of respiratory syncytial virus (RSV) infection in tropical and developing countries; the data currently available have been reviewed. In most studies, RSV was found to be the predominant viral cause of acute lower respiratory tract infections (ALRI) in childhood, being responsible for 27-96% of hospitalised cases (mean 65%) in which a virus was found. RSV infection is seasonal in most countries; outbreaks occur most frequently in the cold season in areas with temperate and Mediterranean climates and in the wet season in tropical countries with seasonal rainfall. The situation on islands and in areas of the inner tropics with perennial high rainfall is less clear-cut. The age group mainly affected by RSV in developing countries is children under 6 months of age (mean 39% of hospital patients with RSV). RSV-ALRI is slightly more common in boys than in girls. Very little information is available about the mortality of children infected with RSV, the frequency of bacterial co-infection, or the incidence of further wheezing after RSV. Further studies on RSV should address these questions in more detail. RSV is an important pathogen ill young children in tropical and developing countries and a frequent cause of hospital admission. Prevention of RSV infection by vaccination would have a significant impact on the incidence of ALRI in children in developing countries.     

Pressure-induced phase transition of quartz-type GaPO4

This study attempted to identify the determinants of acute lower respiratory-tract infections (ALRI) among children under five years of age, by comparing hundred children hospitalized with ALRI with a control group. Data on socio-demographic, biological and environmental characteristics were collected by interviewing mothers and anthropometric measurements were carried out to assess the nutritional status of the children. Risk of disease in the presence of each exposure was calculated in the univariate analysis and the best explanatory variables among them were identified in the multivariate analysis. The following variables were found to increase the risk of ALRI: (1) history of wheezing, (2) low birth weight, (3) passive smoking, (4) male sex, (5) delivery by cesarean section (6) sharing of sleeping space, (7) not being exclusively breast fed upto the completion of four months, (8) stunting, (9) having pets. The findings highlight some simple strategies which would help in prevention of ALRI.     

US-assisted bronchoscopy: is seeing believing?

The Streamline (Menlo Care, Menlo Park, CA) intravenous catheter is constructed of an elastomeric hydrogel (Aquavene) that softens and increases in diameter when exposed to aqueous solutions. The flow rates of 22-gauge x 1', 24-gauge x 0.7', and 26-gauge x 0.625" catheters were ascertained during 90 minutes of hydration in 37 degrees C normal saline. Ten tests of each size catheter were performed every 15 minutes starting at 0 minutes and continued throughout the 90-minute period of hydration. Each test consisted of measuring the time for 10 ml of saline to flow through the catheter. All three gauges had a significant increase in flow and reached a maximum at the 75 minute test. Maximum increase in flow rates were 43, 39, and 32% for the 22-, 24-, and 26-gauge catheters, respectively. None of the catheters exceeded the initial flow rate of the next larger gauge catheter.     

Proteolytic processing of ricin A chain is not required for cytotoxicity

PURPOSE: To evaluate prospectively the use of peripherally inserted central catheters in a large pediatric population. MATERIALS AND METHODS: During a 3-year period, data were collected prospectively on 523 consecutive attempts to place peripherally inserted central catheters in children. Patients underwent radiologically guided placement because attempts were unsuccessful on the inpatient units or a patient request was made. Fluoroscopy with use of contrast material and venography were used to place catheters and document the position of the catheter tip. Follow-up data were collected until treatment cessation or catheter removal. RESULTS: Among 523 attempts, 486 (92.9%) catheters were successfully placed. In the 37 (7.1%) unsuccessful cases, more than half of these children were younger than 24 months of age or weighed less than 5 kg. Ages of patients in whom 523 placement attempts were made ranged from 3 weeks to 18 years (mean, 6.9 years). Catheters were in place from 1 to 390 days (mean, 20 days). Frequency of infection was 1.9% (nine cases); incidence of infection was 0.93 per 1,000 catheter-placement days. There were two cases (0.4%) of central venous thrombosis. Most patients were discharged within 2 days of catheter placement. CONCLUSION: Fluoroscopically guided placement of peripherally inserted central catheters is a safe and effective method for establishing intermediate- and long-term central venous access in the pediatric population.     

Transient up-regulation of ciliary neurotrophic factor receptor-alpha mRNA in axotomized rat septal neurons

PURPOSE: To determine prospectively the feasibility, complications, and mid- and long-term advantages of peripheral insertion of central catheters in infants and children. MATERIALS AND METHODS: During a 15-month period between March 1995 and June 1996, a total of 285 catheter placement attempts were made to peripherally insert central catheters in 183 pediatric patients (89 boys, 94 girls). Phlebographic guidance was used, and the catheters were inserted below the elbow in 99% of cases. Catheter insertion was indicated for prolonged antibiotic therapy in 108 patients (158 catheter placement attempts), hematologic or oncologic care in 24 patients (40 attempts), total parenteral nutrition in 16 patients (46 attempts), and venous access for fluid or blood in 35 patients (41 attempts). The success rate and complications were recorded along with the indication, patient age, and duration of catheter placement. RESULTS: One hundred fifty-two of 158 (96%) catheter placement attempts were successful in outpatients (n = 108), 124 of 127 (98%) in hospitalized patients (n = 75), and 70 of 73 (96%) in patients aged less than 1 year. Infection and pericatheter venous thrombosis were the main complications and were seen in 17 of 276 (6%) and one of 276 (0.3%) catheter placement attempts, respectively. Catheter occlusion occurred in 23 of 276 (8%) catheter placement attempts. CONCLUSION: Peripheral insertion of central catheters was highly feasible in infants and children with this protocol. Such catheters were well tolerated in the pediatric population with a low frequency of complications.     

Anesthesia in two patients with essential thrombocythemia

Case 1. The patient was a 69-year-old man with essential thrombocythemia (ET), who underwent urgent laparotomy. On admission he was dehydrated and the platelet count was more than 160 x 10(4).microliter-1, with hematocrit of 50%. Anesthesia was induced with ketamine i.v. and maintained with nitrous oxide and sevoflurane in oxygen. Postoperative care included the administration of gabexate mesilate (GM) which is an antiplatelet agent. Case 2. An 84-year-old woman with ET was diagnosed as gastric cancer and elective gastrectomy was scheduled. The platelet count was more than 100 x 10(4).microliter-1. The patient was anesthetized with nitrous oxide and oxygen supplemented with fentanyl and mepivacaine via epidural catheter. Intravenous infusion of GM was performed at a rate of 1 mg.kg-1.hr-1 during surgery. PF-4 and beta-TG were measured. These are platelet releasing factors. The level of PF-4 decreased to normal level during this procedure. In conclusions, it will be important to use GM during anesthesia in order to avoid the complications such as myocardial or pulmonary infarction caused by thrombocythemia.     

Simultaneous removal and replacement of infected peritoneal dialysis catheters

Infection is an important complication of peritoneal dialysis that often limits technique survival. Recurrent episodes of peritonitis caused by the same organism may be the result of catheter infection, necessitating removal. We performed 34 single-step catheter replacement procedures in children and young adults for recurrent peritonitis or refractory exit site and tunnel infections. The success rate of the procedure was high (85%), with rare instances of intraoperative contamination. The presence of Staphylococcus aureus infection or exit site and tunnel infection were not risk factors for worse outcome. All patients continued on peritoneal dialysis through catheter change without requiring interval hemodialysis. Eighteen peritoneal dialysis catheters were replaced in a staged procedure with an interval off peritoneal dialysis. There was one early reinfection of the new catheter. Patients with Pseudomonas sp infections were more likely to be treated with a staged procedure; S aureus infections were equally likely to be managed by staged or simultaneous catheter removals. Simultaneous removal and replacement of infected peritoneal dialysis catheters is an effective management strategy when compared with two-step catheter replacements.     

Effect of vitamin A supplementation on diarrhoea and acute lower-respiratory-tract infections in young children in Brazil

A beneficial effect of periodic vitamin A supplementation on childhood mortality has been demonstrated, but the effect on morbidity is less clear. We investigated the effect of vitamin A supplementation on diarrhoea and acute lower-respiratory-tract infections (ALRI) in children from northeastern Brazil in a randomised, double-blind, placebo-controlled community trial. 1240 children aged 6-48 months were assigned vitamin A or placebo every 4 months for 1 year. They were followed up at home three times a week, and data about the occurrence and severity of diarrhoea and ALRI were collected. Any child with cough and respiratory rate above 40 breaths per min was visited by a paediatrician. The overall incidence of diarrhoea episodes was significantly lower in the vitamin-A-supplemented group than in the placebo group (18.42 vs 19.58 x 10(-3) child-days; rate ratio 0.94 [95% Cl 0.90-0.98]). The benefit of supplementation was greater as regards severe episodes of diarrhoea; the incidence was 20% lower in the vitamin A group than in the placebo group (rate ratio 0.80 [0.65-0.98]). With the standard definition of diarrhoea (> or = 3 liquid or semi-liquid stools in 24 h) the effect of vitamin A on mean daily prevalence did not reach significance, but as the definition of diarrhoea was made more stringent (increasing number of stools per day), a significant benefit became apparent, reaching for diarrhoea with 6 or more liquid or semi-liquid stools in 24 h a 23% lower prevalence. We found no effect of vitamin A supplementation on the incidence of ALRI. The reduction in severity of diarrhoea may be the most important factor in the lowering of mortality by vitamin A supplementation.     

Randomised, controlled trial of nasal continuous positive airway pressure in the extubation of infants weighing 600 to 1250 g

AIM: To determine whether extubation to nasal continuous airway pressure (NCPAP) results in a greater proportion of infants remaining free of additional ventilatory support for one week after extubation compared with those extubated directly to headbox oxygen. METHODS: A randomised, controlled, clinical trial was conducted at the neonatal intensive care unit of the Royal Women's Hospital, Melbourne, of infants with birthweights between 600 and 1250 g, ventilated via an endotracheal tube for more than 12 hours, requiring less than 50% oxygen, a ventilator rate < or = 20/minute, considered by the clinical management team to be ready for extubation. Infants were randomly allocated either to NCPAP or to oxygen administered via a headbox. Success was defined by no requirement for additional ventilatory support over the week following extubation. Failure criteria were (i) apnoea; (ii) absolute increase in oxygen requirement greater than 15% above than required before extubation; or (iii) respiratory acidosis (pH < 7.25 with pCO2 > 6.67 kPa). RESULTS: Thirty one of 47 (66%) infants were successfully extubated to NCPAP compared with 18 of 45 (40%) for headbox oxygen. The increase in failure rate in the headbox group was due primarily to increased oxygen requirements in this group. Of the 27 who failed headbox oxygen, 26 were given a trial of NCPAP and 13 did not require endotracheal reintubation. There was no significant difference between the groups in the total number of days of assisted ventilation or the duration of inpatient stay. CONCLUSIONS: NCPAP applied prophylactically after endotracheal extubation reduces the incidence of adverse clinical events that lead to failure of extubation in the seven days after extubation. This reduction is clinically important. The benefits of NCPAP do not seem to be associated with an increased incidence of unwanted side effects.     

Prevention of indwelling central venous catheter sepsis

In an attempt to decrease the incidence of central venous catheter sepsis in children with cancer, we conducted a study to evaluate the benefit of adding broad-spectrum antibiotics to the catheter "flush solution." In a prospective, placebo-controlled, double-blinded, randomized trial, 69 children with different types of malignancies were studied. The central venous catheters in these children were flushed with either the standard solution (normal saline + 100 U/ml of heparin) or the study solution (25 microgram/ml of both amikacin and vancomycin added to the standard solution). At the conclusion of the study, 64 children with a total of 67 indwelling central venous lines were assessable. The total catheter days on study were 20,700 days, with a median of 323 catheter days per patient. We documented 10 events of catheter-related infections (0.49 events/1,000 catheter days at risk). Five of these events were catheter-related sepsis (0.24 sepses/1,000 catheter days): two were fungal and three were bacterial. Due to the low incidence of catheter-related sepsis in this study, no statement regarding the prophylactic use of antibiotics could be made. The extremely low rate of catheter-related sepsis reported herein may be retrospectively attributed to continuous staff education regarding aseptic techniques in handling these catheters. Staff education is essential, and probably the most effective factor in preventing catheter-related sepsis.