Anaesthesia, 1992. Volume 47, pages 1 6 6 176
Correspondence Blood pressure cuff changeover in paediatric anaesthesia G. Sethna G.A. Charlton FFARCS and A . Apadoo Vaporizer tilt - a plea for a level approach J.E.A. Gallagher. FFARCSI. R. Meeke, FFARCSI and G . Manson, MSc, BEng Fatal intra-operative fat embolism C .P. Green, FFA RCS Diamorphine toxicity D. Turner, FFARCS Venous/arterial blood management protection system A . Challiner, FCAnaes, G.B. Smith, FFARCS and B.L. Taylor. FFARCS Dural puncture and depth of the extradural space J . Hamza. MD and D. Benhamou. M D Diclofenac for pain caused by gemeprost pessaries J.S. Rutherford, FCAnaes and D. McKeown. FCAnaes ‘Field’ anaesthesia for an ICU procedure A . Fale, MB. BS. J.A. Carter, FCAnaes and A.R. Manara, MRCP. FCAnaes Failure of Ohmeda Tec 4 Safety Interlock A.J. Hartle and R.E.O. Daum
166 106 I67 168 168 169 169 170 170 171
Airway mucous plug mimicking diaphragmatic herniation G.A. Charlton, FFARCS. K.J. Torlot, FFARCS and C.N. Hacking, M R C P , FRCP Leaking Datex sampling set for end-tidal CO, monitor P.A. Lacoux, MB, BS and G. Christie Dental throat packs and airway protection S.P. Whitley and I.H. Shaw Another antipollution device for the JacksomRees modification of Ayre’s T-piece R.J. Bray, FFARCS Life-threatening tension pneumocephalus after nitrous oxide anaesthesia M . Sprehn, M D , T. Faber, MD and 0. O g a a r d , MD Propofol and excitatory sequelae in rats W.F. de Mello. FCAnaes and E. Kirkman, PhD Pilo-erection in anaphylactoid reaction C.K. Adam, FFARCS Speed of onset of postoperative analgesia H. W . Striebel. MB Yet another use for the laryngeal mask W . Lim, MB, BS
172
173 173 I74 174 174 175 175 175
Blood pressure cuff changeover in paediatric anaesthesia A recent letter (Anaesthesia 1991,46: 898) proposed the use of two three-way taps to switch between paediatric and neonatal hoses/cuffs when using the Dinamap blood pressure monitor. I believe such a practice to be potentially dangerous for the following reasons: ( I ) It would become possible to switch out the transducer from the pump circuit enabling a cuff to be overinflated without protection from the normal safety system. (2) The criteria for cuff sizing (neonatal/adult/paediatric) which is based on tube length may be impaired resulting in inappropriate selection of alarm and overpressure parameters. (3) Partial switching of taps could impair inflation rates and data transmission which could affect the results. (4) The use of two cuffs/air hose assemblies connected to a single unit could result in confusion over which patient has generated the data. I would like to point out that Critikon d o not recommend use of a three-way tap and advise that this technique should not be used. Business Manager Patient Monitoring, Critikon, Ascot, Berkshire SL5 9JN
A reply
We thank Mr Sethna for his useful comments about our letter. Points 1 and 3 would only occur if the three-way taps were incorrectly or only partially turned. All equipment that has the potential for human error should be used with care and we recommend constant vigilance to avoid such mishaps. We were surprised by point 2 as we have used the system described for over a year without any mishap or doubt about the accuracy of pressures obtained. We agree that simultaneous connection to two patients as suggested by point 4 is unsafe and never intended that the equipment should be used in this way. Although no modification to anaesthetic equipment should be undertaken lightly, the system we described has been useful in our practice. Shackleton Department of Anaesthetics, Southampton General Hospital, Southampton SO9 4XY
G.A. CHARLTON A. APADOO
C. SETHNA
All correspondence should he addressed to Dr M , Morgan. Editor of .4naesrhesia, Department of Anaesthetics. Royal Postgraduate Medical School, Hammersmith Hospital, London WI2 OHS. United Kingdom. Letters must be typewritten on one side of the paper only and double spaced with wide margins. Copy should be prepared in the usual style and format of the Correspondence section. Authors must follow the advice about references and other matters contained in the Notice to Contributors to Anaesrhesia printed at the back of each issue. The degrees and diplomas of each author must be given in a covering letter personally signed by all the authors. Correspondence presented in any other style or format may be the subject of considerable delay and may be returned to the author for revision. If rhe Ierrer comments on a published arricle in Anaesthesia. please send rhree copies; otherwise IWO copies of your lerrer will suffice.
Correspondence Blood pressure cuff changeover in paediatric anaesthesia G. Sethna G.A. Charlton FFARCS and A . Apadoo Vaporizer tilt - a plea for a level approach J.E.A. Gallagher. FFARCSI. R. Meeke, FFARCSI and G . Manson, MSc, BEng Fatal intra-operative fat embolism C .P. Green, FFA RCS Diamorphine toxicity D. Turner, FFARCS Venous/arterial blood management protection system A . Challiner, FCAnaes, G.B. Smith, FFARCS and B.L. Taylor. FFARCS Dural puncture and depth of the extradural space J . Hamza. MD and D. Benhamou. M D Diclofenac for pain caused by gemeprost pessaries J.S. Rutherford, FCAnaes and D. McKeown. FCAnaes ‘Field’ anaesthesia for an ICU procedure A . Fale, MB. BS. J.A. Carter, FCAnaes and A.R. Manara, MRCP. FCAnaes Failure of Ohmeda Tec 4 Safety Interlock A.J. Hartle and R.E.O. Daum
166 106 I67 168 168 169 169 170 170 171
Airway mucous plug mimicking diaphragmatic herniation G.A. Charlton, FFARCS. K.J. Torlot, FFARCS and C.N. Hacking, M R C P , FRCP Leaking Datex sampling set for end-tidal CO, monitor P.A. Lacoux, MB, BS and G. Christie Dental throat packs and airway protection S.P. Whitley and I.H. Shaw Another antipollution device for the JacksomRees modification of Ayre’s T-piece R.J. Bray, FFARCS Life-threatening tension pneumocephalus after nitrous oxide anaesthesia M . Sprehn, M D , T. Faber, MD and 0. O g a a r d , MD Propofol and excitatory sequelae in rats W.F. de Mello. FCAnaes and E. Kirkman, PhD Pilo-erection in anaphylactoid reaction C.K. Adam, FFARCS Speed of onset of postoperative analgesia H. W . Striebel. MB Yet another use for the laryngeal mask W . Lim, MB, BS
172
173 173 I74 174 174 175 175 175
Blood pressure cuff changeover in paediatric anaesthesia A recent letter (Anaesthesia 1991,46: 898) proposed the use of two three-way taps to switch between paediatric and neonatal hoses/cuffs when using the Dinamap blood pressure monitor. I believe such a practice to be potentially dangerous for the following reasons: ( I ) It would become possible to switch out the transducer from the pump circuit enabling a cuff to be overinflated without protection from the normal safety system. (2) The criteria for cuff sizing (neonatal/adult/paediatric) which is based on tube length may be impaired resulting in inappropriate selection of alarm and overpressure parameters. (3) Partial switching of taps could impair inflation rates and data transmission which could affect the results. (4) The use of two cuffs/air hose assemblies connected to a single unit could result in confusion over which patient has generated the data. I would like to point out that Critikon d o not recommend use of a three-way tap and advise that this technique should not be used. Business Manager Patient Monitoring, Critikon, Ascot, Berkshire SL5 9JN
A reply
We thank Mr Sethna for his useful comments about our letter. Points 1 and 3 would only occur if the three-way taps were incorrectly or only partially turned. All equipment that has the potential for human error should be used with care and we recommend constant vigilance to avoid such mishaps. We were surprised by point 2 as we have used the system described for over a year without any mishap or doubt about the accuracy of pressures obtained. We agree that simultaneous connection to two patients as suggested by point 4 is unsafe and never intended that the equipment should be used in this way. Although no modification to anaesthetic equipment should be undertaken lightly, the system we described has been useful in our practice. Shackleton Department of Anaesthetics, Southampton General Hospital, Southampton SO9 4XY
G.A. CHARLTON A. APADOO
C. SETHNA
All correspondence should he addressed to Dr M , Morgan. Editor of .4naesrhesia, Department of Anaesthetics. Royal Postgraduate Medical School, Hammersmith Hospital, London WI2 OHS. United Kingdom. Letters must be typewritten on one side of the paper only and double spaced with wide margins. Copy should be prepared in the usual style and format of the Correspondence section. Authors must follow the advice about references and other matters contained in the Notice to Contributors to Anaesrhesia printed at the back of each issue. The degrees and diplomas of each author must be given in a covering letter personally signed by all the authors. Correspondence presented in any other style or format may be the subject of considerable delay and may be returned to the author for revision. If rhe Ierrer comments on a published arricle in Anaesthesia. please send rhree copies; otherwise IWO copies of your lerrer will suffice.
