1531 e-Letters

  • Oximetry-detected pulsus paradoxus predicts for severity in paediatric asthma

    We read with interest the paper by Krishnan et al.1 and agree that "pulsus paradoxus" (PP) of the oximetry plethysmogram (pleth) may be useful in assessing severity of acute asthma exacerbations in children. The visual assessment they propose is one of a number of approaches which have been used, with variable success in predicting clinical outcomes2,3,4.

    Rather than pulse amplitude variation associated with respiration, figure 2 in the paper1 shows predominately baseline undulation, at a rate of about 1/5 to 1/6 of pulse rate; no time base nor simultaneous respiratory waveform is included. Can the authors thus be sure that the variation is due to respiration, and if it is, could the baseline variations in fact be associated with respiratory-related changes in peripheral blood volume? As the visual pleth display is dependent on processing by the pulse oximeter, it would be helpful to know more about the oximeter used.

    We have monitored respiration using Respiratory Inductance Plethysmography (RIP) bands simultaneously with oximetry pleth in children with acute wheezing illness using a SOMNOscreen plus recorder (SOMNOmedics GmbH, Germany) with Nonin oximeter module (Nonin Medical Inc., USA). We developed software in MATLAB (The MathWorks Inc., USA) for quantifying pleth pulse amplitude to assess pulsus paradoxus analogous variation. Consistent with Krishnan et al., we found that chil...

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  • Comparisons of febrile infant prediction rules

    Prediction rules to identify young febrile infants with serious bacterial infections (SBI) have been developed by investigators globally. Comparisons of these rules should be conducted by independent parties to avoid conflicts of interest. Two newer prediction rules use procalcitonin (PCT) as an important variable: one rule,[1] created by the authors of the Velasco[2] paper, and the PECARN Febrile Infant Rule[3] created by the authors of this letter. There are important methodological issues which must be considered when evaluating Velasco’s validation of the PECARN study. 1) The Velasco study was a retrospective analysis of a registry at one hospital in Spain, while the PECARN study was prospectively conducted at 20 centers in the United States and analyzed by an independent data center (mitigating investigator bias). 2) The rate of SBI in the Velasco study was 20.5%, much higher than the 9.3% reported by the PECARN study[3] and other investigators.[4] This suggests a different patient population or SBI epidemiology than ours, and/or enrollment bias. 3) Although the PECARN rule (using the urinalysis, absolute neutrophil count [ANC] and PCT) was derived on febrile infants 0-60 days-old, we recommend implementation only on 29-60 day-old infants, as suggested in our article.[3] In the supplement to our article, the PECARN rule using rounded cutoffs (ANC of 4000 cells/mm3 and PCT of 0.5 ng/mL) for simplicity, safety and to decrease the risk of overfitting, performed with simi...

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  • Returning paediatrics to child centred care

    Scott-Jupp et al. recent paper (Effects of consultant residence out-of-hours on acute paediatric admissions1) appeared relevant to myself as a junior doctor at the end of my training. I am interested to know whether there was learning from the resident consultant around discharge behaviour to better understand the differences?

    There were approximately 40% of admissions that stayed less than 12 hours and this group were more likely to be discharged when a consultant was resident. There was no significant difference in discharge rates in children who stayed more than 12 hours1.

    Should the less ill children be attending acute services anyway? Would a service consisting of resident consultants feed into propping up the acute pathway for less ill children?

    A prospective observational study found up to 42.2% of ED presentations over a 14 day period were judged to have been totally avoidable if the family had had better health education2. Studies have previously looked at the appropriateness of paediatric OPD new referrals and suggest that at least 39% of them could be managed by primary care3.

    I wonder whether the expansion of paediatric consultant posts due to increased ED attendance have unwittingly made secondary care reluctant to challenge the status quo of paediatric care delivery despite clear evidence that hospital is not always appropriate? If paediatric ED attendance starts to go down, would the current system become redundant? Other models...

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  • Necrosis of infantile haemangioma is more likely related to natural history rather than to propranolol therapy

    To the editor
    We appreciated the Images in paediatrics ‘Necrosis of infantile haemangioma with propranolol therapy’ by Grech and colleagues1. Nevertheless, we take exception to the Authors’ statement that necrosis is due to propranolol induced-involution for several reasons: first of all, the infant was not receiving a full-dose medication (1.5 mg/kg/day) when propranolol should be given at minimum 2 mg/kg/day. Furthermore, the milestone study by Léauté-Labrèz et al showed that a daily regimen of 3 mg/kg is safe and effective in reducing haemangiomas in a cohort of 456 infants2. We do believe that considering the low dose and the proliferative phase the infant was in3, necrosis was most likely due to natural evolution of the haemangioma than drug-induced involution. The authors do not give precise measurements of the scalp lesion before and during treatment, so it is not clear how much the lesion diminished in size. In view of previous considerations, it is difficult to rule out that the lesion might just have followed its natural course. As a matter of fact, both prematurity and female gender are well known risk factors associated with ulceration4.As the authors properly underline, propranolol therapy is the treatment of choice for infantile haemangioma (IH) and adverse effects as hypoglycemia, hypotension and bradycardia are widely known. Ulceration is the most common complication of IH and so that it could be even considered an indication to continue rather than...

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  • The risk of ibuprofen-related acute kidney injury is just as important

    The question of the safety of ibuprofen in lower respiratory tract infection(LRTI)(1) should be part of a bigger question. That question is the issue of the safety of ibuprofen in a child who is at risk of dehydration. A febrile child with LRTI is at risk of dehydration because of increased insensible fluid loss via the skin. Furthermore, in the presence of LRTI-related tachypnoea, there will be increased insensible fluid loss via the upper respiratory tract . These fluid losses are compounded when the child is too ill to maintain a good oral fluid intake.
    In volume depleted states, such as the scenario depicted above, vasodilatory prostaglandins maintain adequate renal blood flow(RBF) and adequate glomerular filtration rate(GFR)(2). Nonsteroidal anti inflammatory drugs(NSAIDs) undermine those compensatory mechanisms by inhibiting prostaglandin synthesis(2). The consequence is the onset of NSAID-related acute kidney injury(AKI), as postulated by Misurac et al(3). These investigators postulated that NSAID-related inhibition of prostaglandin synthesis was the underlying cause of AKI in 21 of their 27 cases of NSAID-related AKI. In the remaining 6 children with AKI, acute interstitial nephritis(also attributable to NSAIDs) was the underlying cause.. Fifteen of the 20 children for whom dosing data were available took NSAID doses in the recommended range. Ibuprofen was the culprit NSAID in 67% of cases. Misurac et al also identified 54 other cases...

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  • Response letter to Nutritional rickets under 16 years: UK surveillance results

    Dear Editor

    Infant vitamin D supplementation prevents not just rickets but also hypocalcaemic seizures and cardiomyopathy (CMP). The BPSU survey (1) captures rickets incidence which, we feel compelled to highlight, represents only the tip of the iceberg of widespread vitamin D deficiency (VDD) in the population.

    In the UK, child surveillance checks are led by general practitioners (GPs). Most GPs do not receive postgraduate paediatric training and have inadequate undergraduate paediatric exposure, as acknowledged by the RCPCH president: “by any stretch of the imagination, GP training in the UK in paediatrics is woefully inadequate” (2). Recognising rickets requires paediatric experience as exemplified by recent cases of VDD induced CMP- one child’s death was preceded by multiple unfruitful visits to GPs and casualty (3). As the BPSU survey reached out only to paediatricians and not GPs, the extent of underreporting and under diagnosis is likely huge, limiting comparison with countries where paediatricians oversee primary care. The conclusion that rickets incidence in the UK is lower than expected downplays the extent of the underlying public health crisis, particularly when a significant number of cases were excluded [table 2 of (1)]. The true disease burden is unravelled when family members of affected children are investigated (3).

    Similar to previous studies, rickets incidence here is 90 to 166 fold higher in Asian and Black children compared to wh...

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  • Letter to Editor Nebulised hypertonic saline in moderate-to-severe bronchiolitis: a randomised clinical trial. Raphaelle Jaquet-Pilloud, Marie-Elise Verga, Michel Russo, Mario Gehri, Jean-Yves Pauchard

    Dear Editor

    We enjoyed reading the study by Jaquet-Pilloud et al. 1 examining the role of nebulised 3% hypertonic saline (HS) and bronchiolitis. We thank the authors for this excellent pragmatic non-blinded, randomised controlled trial. Their conclusions support the UK evidence from the SABRE study 2 and their systematic review3 which provides evidence of the futility of adding hypertonic saline to the management of bronchiolitis when compared to standard care alone with length of stay (LOS) or ready for discharge as the primary outcome. The article was well written and easy to follow. The study examined 121 infants with bronchiolitis recruited over three years from one tertiary centre in Switzerland. We felt it illustrated the very important problem of underpowered studies concluding no differences between two treatment regimens. The authors used the Korppi et al 3 study to assume that the mean LOS for infants admitted to hospital with bronchiolitis was 5 days [120 hours] with a standard deviation of 1.2 days [28.8 hours]. Reduction in hospital stay by 1 day was considered clinically significant and based on this a minimum sample size of 120 (with 60 in each group) was arrived. However the data from this paper by Jaquet-Pilloud et al show that the mean LOS was 47 hours (± 8.5) for nebulised hypertonic saline group and 50.4 hours (±11) for standard care group. The LOS at the authors’ hospital was less than half of the assumption used for their power calculation....

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  • Response to Dr Whitaker's letter

    Dr Whitaker, in a letter in response to our Archimedes review of whether waveform capnography reliably approximates paCO2 in neonates, highlights two important questions which capnography seeks to address: Firstly, whether or not the endotracheal tube (ETT) is patent and correctly positioned in the trachea and secondly, whether the current ventilation strategy provides optimal CO2 clearance for the patient. The two questions are, of course, interlinked.
    To date, in our field of neonatal medicine, the ETCO2 provides a valuable adjunct to clinical examination in determining ETT position and patency both at the point of intubation and during ongoing mechanical ventilation. However, for reasons explained in the paper, the numerical approximations to alveolar pCO2 provided by the currently available techniques of wave form capnography in neonates are not accurate enough to guide ventilatory changes. Thus, to guide ventilator changes, many neonatal intensive care units currently use transcutaneous capnometry.
    In addition to the physiological properties, the waveform capnography sensors add extra weight and dead space to an infant’s ventilator circuit. This adds further complexity, like their still not fully assessed effect on volume-guarantee ventilation and potential for auto-triggering of ventilators. As volume guarantee is now considered the gold standard for ventilating preterm infants with respiratory distress syndrome, the value of waveform capnography, in addi...

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  • Prof Tim Cook

    Dear Editor
    We read with interest Dr Scrivens et al’s commentary [1]. The mother’s question - ‘should capnography be used for breathing tube monitoring?’ – captures the subject addressed in our ‘PICNIC survey’ [2]. Conversely, the authors examine a completely different question - ‘is capnography an optimum respiratory monitor in ventilated neonates?’
    A respiratory monitor detects whether the end-tidal CO2 value usefully measures pulmonary ventilation or PaCO2. Although not our focus here, we are surprised the review omitted Kugelman’s study which reported waveform capnography monitoring in neonatal ICU (NICU) improved ventilation accuracy and neurological outcomes [3].
    An airway monitor assesses ‘whether lung ventilation is taking place via a tracheal tube that is in the airway and is patent’. High rates of neonatal failed intubation, oesophageal intubation, accidental extubation and reports of associated patient harm all suggest the value of a reliable airway monitor in NICU. Waveform capnography rapidly detects correct intubation with few false positives and immediately detects displacement or disconnection, the evidence for which we have previously set out [4-6].
    Some neonatologists argue that continuous waveform capnography cannot be used in neonates. It is used routinely in neonatal anaesthesia. Others use it routinely during transfer of small neonates (eg 400g) (personal communication Dr James Tooley, Consultant, Bristol) sometimes only for it...

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  • Multiple café-au-lait macules and Legius syndrome

    Dear authors,
    I read with great interest your article on multiple café-au-lait macules and movement disorder (1). I want to point out that probably an error happened during formatting of table 1. The term RASopathies is used to refer to a group of diseases caused by a mutation in a gene coding for a key component of the RAS-pathway and resulting in hyperactivation of the pathway. This group commonly includes Noonan syndrome, Neurofibromatosis type 1, Legius syndrome, LEOPARD syndrome (now referred to as Noonan syndrome with multiple lentigines), Costello syndrome, CFC syndrome, hereditary gingival fibromatosis, capillary malformation-arteriovenous malformation and Loh syndrome (2). It is confusing to find RASopathies next to Noonan, Legius and LEOPARD syndrome in the same column of table 1. In the same column Legius syndrome is listed as well as NF-like syndrome. Legius syndrome is listed followed by (PTPN11) and NF-like syndrome is followed by the gene (SPRED1). PTPN11 should be listed after Noonan syndrome because it is the most frequent cause of Noonan syndrome and it is not related to Legius syndrome. Legius syndrome is the same as NF1-like syndrome and only one of the two should be listed followed by (SPRED1). In our first publication (3) we named the condition neurofibromatosis 1-like syndrome but later is was renamed Legius syndrome (4).
    Congenital mismatch repair deficiency (CMMRD) is another autosomal recessive condition with café-au-lait macules and...

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