Anaesthesia 2015, 70, 997–1010
Correspondence
Table 1 Variation in coagulation test results for haemostasis by degree of contamination with 0.9% saline. Values are mean (SD). Contamination
PT; s Fibrinogen; g.l1 D-dimer; ng.ml1 APTT; s
None
5%
p value
10%
p value
20%
p value
10.8 (0.7) 4.2 (0.7)
11.2 (0.8) 3.9 (0.7)
0.2059 0.3052
11.6 (0.8) 3.7 (0.7)
0.0161 0.0941
12.4 (1.0) 3.3 (0.6)
0.0002 0.0027
84 (52)
73 (43)
0.5780
67 (42)
0.3878
56 (36)
0.1394
29.6 (2.9)
29.3 (2.6)
0.7921
29.0 (2.4)
0.5864
29.2 (2.4)
0.7163
bin time (PT), activated partial thromboplastin time (APTT), fibrinogen and D-dimer using an ACL TOP 700 (Instrumentation Laboratory, Bedford, MA, USA). Comparisons between contaminated and uncontaminated samples were analysed using Student’s t-test and Analyse-it software (Analyse-it Software Ltd, Leeds, UK). Results are shown in Table 1. The administration of 0.9% saline is commonplace in healthcare [3, 4]. The results of this study suggest that dilution of venous blood samples with contaminant 0.9% saline solution may significantly prolong PT and reduce the measured fibrinogen concentration. G. Lippi R. Buonocore M. Di Pietro L. Ippolito Academic Hospital of Parma, Parma, Italy Email: ulippi.tin.it E. J. Favaloro Westmead Hospital, Westmead, Australia No external funding and no competing interests declared. Previously posted on the Anaesthesia correspondence website: www.anaesthesia correspondence.com. 1002
References 1. Lippi G, Buonocore R, Musa R, Ippolito L, Picanza A, Favaloro EJ. The effect of hyperglycaemia on haemostasis testing – a volunteer study. Anaesthesia 2015; 70: 549–54. 2. Ricos C, Alvarez V, Cava F, Garcia-Lario JV, et al. Current databases on biologic variation: pros, cons and progress. Scandinavian Journal of Clinical and Laboratory Investigation 1999; 59: 491–500. 3. Doherty M, Buggy DJ. Intraoperative fluids: how much is too much? British Journal of Anaesthesia 2012; 109: 69–79. 4. Association of Anaesthetists of Great Britain and Ireland. Arterial line blood sampling: preventing hypoglycaemic brain injury 2014. Anaesthesia 2014; 69: 380–5.
nation of general anaesthesia with multimodal pain therapy, including systemic analgesics, local or regional anaesthesia [1]. This is similar to consensus advice recommended by Strategies for Mitigating AnesthesiaRelated Neurotoxicity in Tots (SmartTots) for reducing potential neurotoxic consequences of general anaesthesia in children, but stops short of advocating surgical intervention only in ‘urgent’ cases, as recommended by SmartTots for children under three years of age [2]. We agree with Sinner et al. that exposure to general anaesthesia should be minimised, but think that the SmartTots initiative needs to be far more specific about which types of surgery fall within their definition of ‘urgent’ before clinicians and parents can consider restricting access to the overwhelming benefit of general anaesthesia, in order to avoid the currently rather nebulous but seemingly rather small risk of neurotoxicity.
doi:10.1111/anae.13151
Paediatric anaesthesia neurotoxicity and the ‘urgency’ of surgery In their recent review, Sinner et al. claim that general anaesthesia may be toxic to the developing brain by interfering with neurogenesis, leading to impaired neurocognitive function later in life. They recommended reducing overall drug dosage by keeping anaesthesia and surgery times as short as possible, using short-acting drugs and/or a combi-
F. Sanchis-Gomar Research Institute of the Hospital 12 de Octubre (“i+12”), Madrid, Spain Email: [email protected] J. Cortell-Ballester Universitary and Polytechnic Hospital La Fe, Valencia, Spain C. Perez-Quilis University Research Institute “Dr. Vi~ na Giner”, Valencia, Spain
No external funding and no copmeting interests declared. Previously posted on the Anaesthesia correspondence website: www.anaesthesia correspondence.com.
© 2015 The Association of Anaesthetists of Great Britain and Ireland
Correspondence
Anaesthesia 2015, 70, 997–1010
References 1. Sinner B, Becke K, Engelhard K. General anaesthetics and the developing brain: an overview. Anaesthesia 2014; 69: 1009–22. 2. Rappaport BA, Suresh S, Hertz S, Evers AS, Orser BA. Anesthetic neurotoxicity – clinical implications of animal models. New England Journal of Medicine 2015; 372: 796–7. doi:10.1111/anae.13152
Suction tube-facilitated videolaryngoscopic intubation We thank Kelly and Seller for sharing their gum-elastic bougie ‘snail’ technique for aiding successful placement of bougies during videolaryngoscopy [1]. Similarly, we frequently find the problem of a superior view but difficulty passing a tracheal tube or bougie when using a curved-blade videolaryngoscope without a conduit (e.g. C-MACâ, Karl Storz GmBH & Co. KG, Tuttlingen, Germany). This becomes particularly problematic
when placing narrow-calibre microlaryngeal tubes or ‘laser tubes’ for airway surgery, as the smaller bougies required lack the rigidity to maintain a curved shape during intubation. We have found that a 22-Fr Yankauer suction tube (Covidien, Mansfield, MA, USA) can function as a useful rigid conduit through which a paediatric 10-Fr bougie (P3 Medical, Bristol, UK) can be passed in such cases, as the curvature of the Yankauer tube is similar to that of the C-MAC blade (Fig. 2). The Yankauer tube can then be removed and the tracheal tube railroaded over the bougie. J. Masters T. Rope Northwick Park Hospital, London, UK Email: [email protected] No external funding and no competing interests declared. Previously posted on the Anaesthesia correspondence website: www.anaesthesia correspondence.com.
Figure 2 Yankauer sucker over a paediatric bougie to assist videolayngoscopic intubation. © 2015 The Association of Anaesthetists of Great Britain and Ireland
Reference 1. Kelly FE, Seller C. Snail trail. Anaesthesia 2015; 70: 501. doi:10.1111/anae.13170
Fractured laryngeal mask During magnetic resonance imaging (MRI), the reservoir bag attached to T-piece breathing system connected to a size-2 Flexicareâ LarysealTM (Flexicare Medical Ltd, Mountain Ash, UK) MRI laryngeal mask was noted not to be moving, with a flat capnography trace. Insertion of the laryngeal mask had been uneventful. The patient’s breathing appeared unobstructed, SpO2 was normal and there was no immediately apparent disconnection. Ventilating the patient’s lungs via the T-piece was not possible and a large leak was heard from the mouth. Suspecting dislodgement of the laryngeal mask, removal and reinsertion were reattempted, but during removal, the airway tube separated from the cuff (Fig. 3). The cuff remained in the oropharynx, but was easy to retrieve by hand. A new laryngeal mask was inspected and inserted, and anaesthesia continued uneventfully. The Medicines and Healthcare products Regulatory Agency (MHRA) was notified and devices with the same batch number were withdrawn from circulation. To our knowledge, this is only the second reported case of such a failure in a single-use laryngeal mask [1], although there have been several case reports of breakages of re-usable devices [2–5]. Although 1003
Correspondence
Table 1 Variation in coagulation test results for haemostasis by degree of contamination with 0.9% saline. Values are mean (SD). Contamination
PT; s Fibrinogen; g.l1 D-dimer; ng.ml1 APTT; s
None
5%
p value
10%
p value
20%
p value
10.8 (0.7) 4.2 (0.7)
11.2 (0.8) 3.9 (0.7)
0.2059 0.3052
11.6 (0.8) 3.7 (0.7)
0.0161 0.0941
12.4 (1.0) 3.3 (0.6)
0.0002 0.0027
84 (52)
73 (43)
0.5780
67 (42)
0.3878
56 (36)
0.1394
29.6 (2.9)
29.3 (2.6)
0.7921
29.0 (2.4)
0.5864
29.2 (2.4)
0.7163
bin time (PT), activated partial thromboplastin time (APTT), fibrinogen and D-dimer using an ACL TOP 700 (Instrumentation Laboratory, Bedford, MA, USA). Comparisons between contaminated and uncontaminated samples were analysed using Student’s t-test and Analyse-it software (Analyse-it Software Ltd, Leeds, UK). Results are shown in Table 1. The administration of 0.9% saline is commonplace in healthcare [3, 4]. The results of this study suggest that dilution of venous blood samples with contaminant 0.9% saline solution may significantly prolong PT and reduce the measured fibrinogen concentration. G. Lippi R. Buonocore M. Di Pietro L. Ippolito Academic Hospital of Parma, Parma, Italy Email: ulippi.tin.it E. J. Favaloro Westmead Hospital, Westmead, Australia No external funding and no competing interests declared. Previously posted on the Anaesthesia correspondence website: www.anaesthesia correspondence.com. 1002
References 1. Lippi G, Buonocore R, Musa R, Ippolito L, Picanza A, Favaloro EJ. The effect of hyperglycaemia on haemostasis testing – a volunteer study. Anaesthesia 2015; 70: 549–54. 2. Ricos C, Alvarez V, Cava F, Garcia-Lario JV, et al. Current databases on biologic variation: pros, cons and progress. Scandinavian Journal of Clinical and Laboratory Investigation 1999; 59: 491–500. 3. Doherty M, Buggy DJ. Intraoperative fluids: how much is too much? British Journal of Anaesthesia 2012; 109: 69–79. 4. Association of Anaesthetists of Great Britain and Ireland. Arterial line blood sampling: preventing hypoglycaemic brain injury 2014. Anaesthesia 2014; 69: 380–5.
nation of general anaesthesia with multimodal pain therapy, including systemic analgesics, local or regional anaesthesia [1]. This is similar to consensus advice recommended by Strategies for Mitigating AnesthesiaRelated Neurotoxicity in Tots (SmartTots) for reducing potential neurotoxic consequences of general anaesthesia in children, but stops short of advocating surgical intervention only in ‘urgent’ cases, as recommended by SmartTots for children under three years of age [2]. We agree with Sinner et al. that exposure to general anaesthesia should be minimised, but think that the SmartTots initiative needs to be far more specific about which types of surgery fall within their definition of ‘urgent’ before clinicians and parents can consider restricting access to the overwhelming benefit of general anaesthesia, in order to avoid the currently rather nebulous but seemingly rather small risk of neurotoxicity.
doi:10.1111/anae.13151
Paediatric anaesthesia neurotoxicity and the ‘urgency’ of surgery In their recent review, Sinner et al. claim that general anaesthesia may be toxic to the developing brain by interfering with neurogenesis, leading to impaired neurocognitive function later in life. They recommended reducing overall drug dosage by keeping anaesthesia and surgery times as short as possible, using short-acting drugs and/or a combi-
F. Sanchis-Gomar Research Institute of the Hospital 12 de Octubre (“i+12”), Madrid, Spain Email: [email protected] J. Cortell-Ballester Universitary and Polytechnic Hospital La Fe, Valencia, Spain C. Perez-Quilis University Research Institute “Dr. Vi~ na Giner”, Valencia, Spain
No external funding and no copmeting interests declared. Previously posted on the Anaesthesia correspondence website: www.anaesthesia correspondence.com.
© 2015 The Association of Anaesthetists of Great Britain and Ireland
Correspondence
Anaesthesia 2015, 70, 997–1010
References 1. Sinner B, Becke K, Engelhard K. General anaesthetics and the developing brain: an overview. Anaesthesia 2014; 69: 1009–22. 2. Rappaport BA, Suresh S, Hertz S, Evers AS, Orser BA. Anesthetic neurotoxicity – clinical implications of animal models. New England Journal of Medicine 2015; 372: 796–7. doi:10.1111/anae.13152
Suction tube-facilitated videolaryngoscopic intubation We thank Kelly and Seller for sharing their gum-elastic bougie ‘snail’ technique for aiding successful placement of bougies during videolaryngoscopy [1]. Similarly, we frequently find the problem of a superior view but difficulty passing a tracheal tube or bougie when using a curved-blade videolaryngoscope without a conduit (e.g. C-MACâ, Karl Storz GmBH & Co. KG, Tuttlingen, Germany). This becomes particularly problematic
when placing narrow-calibre microlaryngeal tubes or ‘laser tubes’ for airway surgery, as the smaller bougies required lack the rigidity to maintain a curved shape during intubation. We have found that a 22-Fr Yankauer suction tube (Covidien, Mansfield, MA, USA) can function as a useful rigid conduit through which a paediatric 10-Fr bougie (P3 Medical, Bristol, UK) can be passed in such cases, as the curvature of the Yankauer tube is similar to that of the C-MAC blade (Fig. 2). The Yankauer tube can then be removed and the tracheal tube railroaded over the bougie. J. Masters T. Rope Northwick Park Hospital, London, UK Email: [email protected] No external funding and no competing interests declared. Previously posted on the Anaesthesia correspondence website: www.anaesthesia correspondence.com.
Figure 2 Yankauer sucker over a paediatric bougie to assist videolayngoscopic intubation. © 2015 The Association of Anaesthetists of Great Britain and Ireland
Reference 1. Kelly FE, Seller C. Snail trail. Anaesthesia 2015; 70: 501. doi:10.1111/anae.13170
Fractured laryngeal mask During magnetic resonance imaging (MRI), the reservoir bag attached to T-piece breathing system connected to a size-2 Flexicareâ LarysealTM (Flexicare Medical Ltd, Mountain Ash, UK) MRI laryngeal mask was noted not to be moving, with a flat capnography trace. Insertion of the laryngeal mask had been uneventful. The patient’s breathing appeared unobstructed, SpO2 was normal and there was no immediately apparent disconnection. Ventilating the patient’s lungs via the T-piece was not possible and a large leak was heard from the mouth. Suspecting dislodgement of the laryngeal mask, removal and reinsertion were reattempted, but during removal, the airway tube separated from the cuff (Fig. 3). The cuff remained in the oropharynx, but was easy to retrieve by hand. A new laryngeal mask was inspected and inserted, and anaesthesia continued uneventfully. The Medicines and Healthcare products Regulatory Agency (MHRA) was notified and devices with the same batch number were withdrawn from circulation. To our knowledge, this is only the second reported case of such a failure in a single-use laryngeal mask [1], although there have been several case reports of breakages of re-usable devices [2–5]. Although 1003
