Recent eLetters

Thank you for your response to our research 'The agreement of fingertip and sternum capillary refill time (CRT) in children'

We agree that there is a lack of gold standard for assessing tissue perfusion in a simple and timely manner and continue to extrapolate that in shock, blood is usually diverted from the skin in an attempt to perfuse vital organs. Current practice and guidance assumes that CRT is a reflection of this (1-7). We were not expecting to find fingertip CRT to be faster than sternum CRT, although we did not find it strange. We agree and also suspect that different sites have different refill times because of the complex and intricate relationships involved, which are not practical or possible to record prior to carrying out the CRT (such as arteriolar resistance, venular resistance etc. as discussed in Carcillo (1)). There is a substantial amount of research in CRT in vascular medicine which we decided not to include in our literature review prior to this study, although our findings might indicate it would be more appropriate to examine this area in more detail. We do know that the fingertip pulp is rich in arterio-venous anastomoses which may explain why it had the quickest CRT and that vascular resistance is increased in peripheral beds and this may explain why it also had the slowest CRT.

We agree that there needs to be standardisation of the technique, greater awareness of CRT limitations and it should be analysed in conjunction with other haemodynamic markers. We suggested that guidance provided by the Resuscitation Council (RC) (2-4), amongst others, be reviewed for exactly these reasons. The RC highlight CRT as one of the five parameters to observe when examining circulation, giving it equal weighting to heart rate, pulse volume, blood pressure and end organ perfusion status. The RC guidance does advise to consider CRT with other cardiovascular signs but importantly does not consider the fingertip site or variables such as inter and intra observer reliability and skin colour.

Carcillo's editorial is interesting; however this purposive review is not balanced or systematic and does not provide a comprehensive overview of the literature relating to CRT. Interestingly although Carcillo is discussing sick children we are informed that CRT is age dependant and rightly references the study that discovered this in 1988, there is no evidence that tells us otherwise, yet we can find no guidance by the RC or other group that utilises an age dependant model, why is that?

Our study did not set out to examine the usefulness of the test, but led us to question the way CRT is conducted in current clinical practice. In an era where we try to practice evidence based medicine, if this test is recommended for use in practice (something our research cannot answer) then we have a duty to generate the evidence to support the way in which it is conduced.

1. Carcillo JA. Capillary refill time is a very useful clinical signin early recognition and treatment of very sick children. Editorial on Pediatr Crit Care Med 2012; 13:136 -140

2. Resuscitation Council. Medical Emergencies and Resucitation-- Standards for clinical practice and training for dental practitioners and dental care professionals in general dental practice. http://www.resus.org.uk/pages/MEdental.pdf (accessed May 2013):24.

3. Resuscitation Council. European paediatric life support (EPLS). 3rd edn. London:

4. Resuscitation Council 2011:12. Resuscitation Council. A systematic approach to the acutely ill patient, adapted from the ALERTTM. http://www.resus.org.uk/pages/alsABCDE.htm (accessed May 2013).

5. Jevon P. Measuring capillary refill time. Nurs Times 2007;103:26- 7.

6. Lima A, Jansen TC, Van Bommel J, et al. The prognostic value of the subjective assessment of peripheral perfusion in critically ill patients. Crit Care Med 2009;37:934-8.

7. Graham C, Parke T. Critical care in the emergency department: shock and circulatory support. Emerg Med J 2005;22:17-21.

Conflict of Interest:

None declared

Dear Editor,

We read with great interest the article on capillary refill time (CRT) in children. Crook J and Taylor RM have carried out a simple and yet very relevant study on CRT in children.CRT is almost universally checked by child care providers particularly in emergency room or intensive care setting and is taken as a surrogate of the perfusion status. However, two issues have plagued this simple bedside test:

(i) There seems to be no uniformity in the way this test is carried out across the world. We recently published a letter to editor (1) describing the variations in eliciting CRT amongst the various standard texts and references. After analysis of all the references, it seemed prudent to follow the Pediatric advanced life support(PALS )guideline for CRT in children (finger tip) and the WHO guideline for CRT in young infants (finger tip and sternum) with a pressure application of at least 3 seconds. There continue to be issues with eliciting CRT from the peripheries in neonates (2).In the current article ,the authors have rightly suggested a uniform practice for assessing CRT though it wasn't in the purview of their study.

(ii) There have been various studies questioning the utility of CRT .Even the APLS manual suggests use of caution in interpreting CRT as a standalone measure of shock. Another recent article suggests poor inter- rater reliability and poor correlation with cardiac output in non-acutely ill children (3).The confusion with respect to studies on CRT perhaps stems from the lack of a simple gold standard for assessing perfusion status of the tissues. It could be the pulse pressure, skin temperature gradient, central venous oxygen saturations (ScVO2), lactate , near infra red spectroscopy (NIRS) etc or a mixture of such variables. It is also important to remember that in an attempt to perfuse the vital organs in shock , the blood is usually diverted from the skin and hence the delay in CRT is supposed to reflect the degree of shock. As pointed out by Carcillo JA in an excellent editorial(4) ,there are numerous studies supporting the use of CRT and hence it is a useful tool for evaluation of the hemodynamic status in children.

The authors of this current study have carried out both sternal and finger tip CRT in normal children and found that there was a poor correlation between the two. Another interesting finding was that the finger tip CRT was faster than the sternal CRT.This finding is rather strange and seems difficult to fit in despite the complex and intricate relationship between arteriolar resistance, venular resistance, viscosity, microvessel patency, polycythemia etc involved in the capillary refill. It was also premature on part of the authors to consider resuscitation council(RC) to re-evaluate their recommendations on CRT.

It is important for us to ensure that the CRT is carried out with some uniform method by all child care providers and that studies on CRT should consider assessing its utility against a set of surrogate variables of perfusion in the normal and sick children. One must be aware of the limitations of CRT and analyse it in conjunction with the other markers of hemodynamic status. A normal CRT in a sick child except perhaps in warm shock has a good negative predictive value. One could consider inventing a simple device akin to a ball point pen with a stopwatch which delivers a standard pressure for appropriate time on the skin surface so as to make the process of eliciting CRT more uniform. It would be even better if the refill measurement could be digitized to avoid any subjective error. Irrespective of the technique used, a resource limited country is likely to use only clinical signs or low cost devices for assessment of perfusion in sick children with shock.

References:

1. Pandey A,John BM.Capillary refill time:Is it time to fill the gaps.Medical Journal Armed Forces India 2013;69:97-98.

2. Gale C.Is capillary refill time a useful marker of hemodynamic status in neonates? Arch Dis Child 2010; 95:395-397

3. Lobos A,Lee S,Menon K. Capillary refill time and cardiac output in children undergoing cardiac catheterization. Pediatr Crit Care Med 2012; 13:136 -140

4. Carcillo JA. Capillary refill time is a very useful clinical sign in early recognition and treatment of very sick children. Editorial on Pediatr Crit Care Med 2012; 13:136 -140

Conflict of Interest:

None declared

The timely commentary on basilar artery stroke(1) serves as an opportunity to highlight the importance of a high index of suspicion for posterior circulation transient neurological episodes(TNAs)(2), especially in the presence of risk factors for vertebral artery dissection(3). It is also a reminder of the underuse of magnetic resonance imaging(utilised in only 44.3% of 97 children in one review)(4), notwithstanding the fact that it is the modality of choice for distinguishing between transient ischaemic attack(including TNAs) and iscahemic stroke, the distinguishing characteristic of the latter being its assocation with infarction of brain tissue(5). The recognition of the diagnostic and prognostic import of TNAs leaves considerable room for improvement, not only in adults(2), but also in children(4).In the former age group one study reported that 45 out of 275 patients(ie 16%) with brainstem strokes had experienced antecedent TNAs, and that only ten of those patients with TNAs had sought medical attention at the time. More to the point, a vascular cause was suspected by the doctor in only one of those cases(2). Given the higher prevalence of brainstem TNAs among children(43% of 97 patients with eventual basilar artery strokes in one study)(4), even greater use should be made of MRI to establish the distinction between TNA and brainstem stroke. The index of suspicion for attributing brainstem TNA to vertebral artery dissection should also be high if there is an antecedent history of trauma to the neck or head region, as was the case in 50% of 68 childhood instances of vertebral artery dissection reviewed in one publication(3).Although MRI does establish the distinction between TNA and stroke within the therapeutic time window for thrombolysis it is still uncertain whether or not children with stroke should receive thrombolytic therapy(6)(7). Good outcomes were reported in 24 children with basilar artery stroke who did not receive thrombolysis(6), and it has been argued that the benefit vs risk profile of thrombolysis(for basilar artery occlusion) might be different in children as opposed to adults(7). Nevertheless, in one review, 17 of the 97 children with basilar strokes received thrombolysis. One criticism that has been levelled is that, in the rare event of administration of thrombolytic therapy to children to with stroke, dose regimens vary widely, and treatment is often given outside the time intervals recommended for adults(8). These observations reinforce the view that clinical trials to evaluate dose and safety of thrombolytic therapy are needed in childhood stroke(8). References

(1) Archivist Basilar artery stroke Arch Dis Child 2013;98:334 (2)Paul N., Simani M., Rothwell PM Transient isolated brainstem symptoms preceding posterior circulation stroke; a population-based study Lancet Neurology 2013;12:65-71 (3) Hasan I., Wapnick S., Tenner MS.,Couldwell WT Vertebral artery dissection in children: A compreshensive review Pediatric Neurosurgery 2002;37:168-177 (4)Simonetti BG., Ritter B., Gautschi M et al Basilar artery stroke in childhood Developmental Medicine and Child Neurology 2013;55:65-70 (5)Easton JD., Saver JL., Albers GW et al Definition and evaluation of transient ischemic attack. A scientific statement for healthcare professionals from the American Heart Association/American Stroke Association Council; Council on Cradiovascular surgery and anesthesia;Council on cardiovascular radiology and intervention;Council on cardiovascular nursing; and Interdisciplinary council on peripheral vascular disease Stroke 2009;40:2276-2293 (6)Langman-Bartolome M., Pontigon A-M., Moharir M et al Basilar artery strokes in children: good outcomes with conservative medical treatment Develomental Medicine doi: 10.1111/dmen.12092 (7)Deveber G Childhood basilar artery thrombosis: reassuring outcomes in younger patients Developmental Medicine and Child Neurology 2013;55:7-14 (8) Amlie-Lefond C., deVeber G., Chan AK Use of alteplase in childhood artrial ischaemic stroke; a multicentre observational cohort study Lancet 2009;8:530-536

Conflict of Interest:

None declared

We appreciate the interest shown and the comments on our article by Dr. Carlos Loeda.

Bladder stimulation techniques and some primitive reflexes of the newborn,(1,2) may favor the onset of urination. There are few reports on its application in the collection of urine, and results are very heterogeneous.(3,4) Stimulation maneuvers such bladder percussion are long known, and are used routinely in neurogenic bladder.(5)

As stated by Dr. Loeda, J. Boehm et al described in 1966 that they applied Perez reflex for collection of urine samples in 55 newborns. Perez reflex consists on the normal response of an infant when held in a prone position and pressed with a finger along the spine from the sacrum to the neck. The response is described as crying, flexion of the limbs and head elevation and pelvis. It can also trigger urination and defecation. Boehm did not describe any standardized technique, but used the voiding associated to reflex to collect urine. In the paper, there is no report of time to sample collection or success rate.

The main contribution of our study is to design a technique based on a protocolized sequence of fluid intake, use of percussion manoeuvres bladder and lumbar massage. The three points are relevant. Steps and time spent on every step are defined to facilitate reproducibility. We reflected the success rate (86%) and the average time until sample collection (57 seconds). We believe that our group has gone a step further by creating a sequence simple, fast, effective and reproducible. It is associated with a high degree of acceptance by parents and health professionals.

Its utility has been recognized by dozens of compliments we have received from pediatricians from all around the world. We would like to take this opportunity to show our gratitude to all.

References:

1. Carbonell JM, Perez del Pulgar Marx J. Contribucion al estudio de los reflejos del recien nacido y prematuro: complejo por friccion digital vertebral. Rev Espan Pediat 1955;11:317.

2. Vollmer H. A new reflex in Young infants. Amer J Dis Child 1958; 95:481.

3. Davies P, Creenwood R, Benger J. Randomised trial of a vibrating bladder stimulator the time to pee study. Arch Dis Child 2008;93:423-4.

4. Morris B, Vince JD, Ripa P, Tefuarani N. The clean cath technique for urine collection in infants and young children. Trop Doct 2007;37(2):125.

5. Prasad RS, Smith SJ, Wright H. Lower abdominal pressure versus external bladder stimulation to aid bladder emptying in multiple sclerosis: a randomized controlled study. Clin Rehabil 2003;17:42-7.

Conflict of Interest:

None declared

Dear sir:

This article describes what seems to be a very useful method for infant's urine clean catch. But the procedure is not entirely original. In 1966 Boehm and Haynes had proposed a similar method for eliciting reflex urination in infants ("Midstream Catch" Urines Studies in Newborn Infants JOHN J. BOEHM, MD; JAMES L. HAYNES, AB Am J Dis Child. 1966;111(4):366-369). In that paper, the lumbar area stimulation was slightly different, as trying to get a "lower" Perez's reflex.

Sincerely yours

Carlos Loeda MD Staff Pediatritian HGU Alicante Spain

Conflict of Interest:

None declared