Verathon Medical V. Aircraft Medical
| Jurisdiction | Scotland |
| Judge | Lord Hodge |
| Neutral Citation | [2011] CSOH 19 |
| Court | Court of Session |
| Published date | 01 February 2011 |
| Year | 2011 |
| Date | 01 February 2011 |
| Docket Number | A680/07 |
| OUTER HOUSE, COURT OF SESSION [2011] CSOH 19 | |
| A680/07 | OPINION OF LORD HODGE in the cause VERATHON MEDICAL (CANADA) ULC Pursuer; against AIRCRAFT MEDICAL LIMITED Defender: ________________ |
Pursuer: Currie, Q.C., Higgins; Maclay Murray & Spens LLP
Defender: Lake, Q.C., O'Brien; DLA Piper Scotland LLP
1 February 2011
[1] The pursuer is a company incorporated in Nova Scotia, Canada and is a specialist in the field of medical equipment. The defender is a company incorporated in the United Kingdom and is also a manufacturer of medical equipment.
[2] The pursuer is the proprietor of the European Patent (UK) 1 307 131 B1 - "Intubation Instrument" ("the Patent"), which is registered in respect of the United Kingdom. The Patent has priority dates of 7 August 2000 and 6 December 2000. The Patent has been amended in contested proceedings before the Opposition Division of the European Patent Office ("EPO"). In discussing the Patent I refer to the claims as re-numbered after the EPO's amendments.
[3] The pursuer seeks a declarator that the defender has infringed the Patent and, in particular, Claims 1, 4, 5 and 8-16 thereof. The pursuer also seeks interdict and damages, which it states at £37,000,000, which failing, an accounting for the defender's profits from its sale of the McGrath Series 5 laryngoscope. The pursuer also seeks to amend the Patent under section 75 of the Patents Act 1977 ("the 1977 Act") and Rule 55.5 of the Rules of the Court of Session and a declarator that the defender has infringed the added Claims 18 and 19. The defender counter claims for revocation of the Patent on the basis that the alleged invention was not new and, separately, that it lacked an inventive step.
[4] By interlocutor dated 28 January 2009 Lady Smith allowed parties a proof before answer on the issues of (i) infringement of the Patent, (ii) the defender's application for its revocation and (iii) the pursuer's application to amend the Patent.
[5] The parties agreed in a Joint Minute that as at 11 January 2010 the defender had "manufactured, used, kept (for disposal or otherwise), marketed, offered to dispose of/sell, and disposed of/sold Series 5 laryngoscopes in the United Kingdom" and that the defender continues to do so.
Background
(i) Endotracheal intubation
[6] A laryngoscope is, as its name suggests, a medical device for visualising the larynx. Anaesthetists and, in North America, practitioners of emergency medicine use the device to facilitate intubation of a patient, either in the context of elective surgery or in an emergency, such as a severe injury. Intubation is a means of managing a patient's airway, providing him (and I will say this only once) or her with oxygen and removing carbon dioxide and other waste products of respiration. Successful airway management is essential to such a patient's survival. In order to place an endotracheal tube in a patient's trachea (or windpipe) the medical practitioner usually needs to obtain a view of the glottis, which is the opening of the larynx between the vocal cords. Routine intubation is normally carried out on a patient who has been given anaesthetic drugs to induce general anaesthesia and neuromuscular paralysis. It is necessary to describe briefly the relevant anatomy of the patient in order to understand much of the evidence which the parties led in this proof.
[7] The safety and success of intubation depend in large measure on the obtaining of a good view of the glottis so that the medical practitioner can observe the endotracheal tube entering the larynx, whereby it is placed in the trachea which serves the lungs. Human anatomy does not make it an easy task to obtain a straight line of sight from outside a patient's mouth to the glottis. A standing patient's oral cavity is broadly on a horizontal plane ("the oral axis") while his pharynx (the cavity forming the upper part of the gullet, lying behind the nose, mouth and larynx) is close to the vertical plane ("the pharyngeal axis"). The larynx is located in front of the pharynx and so the axis from the back of the mouth ("the posterior oropharynx") to the larynx ("the laryngeal axis") of the standing patient tilts forward from the vertical as it descends. Thus the line of sight from outside the patient's mouth to the glottis must first traverse the patient's oral cavity to the posterior oropharynx and then angle forward at approximately 90º to reach the glottis. When the patient is lying on his back on the operating table in a neutral position the same angle exists but the oral axis is broadly vertical and the laryngeal axis is broadly horizontal. Patients are normally intubated under general anaesthesia; the axes are therefore generally in the latter positions when the medical practitioner starts his attempt to intubate.
[8] In order to create a direct line of sight from outside the mouth to the glottis the medical practitioner has to move the neck and head of the patient who is lying on the operating table, by flexing forward the neck on the body and then extending the head on the neck, so as to place the patient in what is known as the "sniffing position". Thereafter, the medical practitioner must insert the laryngoscope and use force to displace tissues to create the direct line of sight.
[9] At the back of the tongue there is the vallecula, which is a groove above the epiglottis, which in turn is a cartilaginous flap over the glottis. To obtain a view of the glottis the medical practitioner needs to displace the epiglottis by raising it. He can do so either indirectly or directly. The former method involves the placing of the tip of the laryngoscope into the vallecula and raising the device, thereby creating tension on the hyo-epiglottic ligament and indirectly elevating the epiglottis to expose the glottic aperture. The latter method entails the placing of the tip of the laryngoscope posterior to the epiglottis and lifting the blade on the posterior surface of the epiglottis, thus elevating the epiglottis to create the desired view.
[10] Once the medical practitioner has achieved the direct line of sight he can insert the endotracheal tube through the patient's glottis. The success or failure of intubation depends in large measure on the quality of the view of the glottis which the practitioner achieves by use of the laryngoscope. The Cormack-Lehane system, which was published in 1984, is generally used to define the quality of glottic view. It is based on four pre-defined grades of glottic view; grades 1 and 2 are respectively a full view and a partial view of the glottis. Grade 3 involves no view of the glottis but visualisation of the epiglottis and grade 4 defines the circumstance in which laryngoscopy cannot identify the epiglottis. Research reveals a success rate of almost 100% in the intubation of patients with a grade 1 or grade 2 view while a grade 4 view has a success rate of near zero. Failed intubation risks brain damage or death.
[11] The medical practitioner seeking to intubate a patient faced a serious complication if the patient had a facial, head or neck injury which hampered or prevented the adjustment of his head and neck into the "sniffing position". Medical practitioners engaged in airways management recognised the phenomenon of a "difficult airway", of which there were several definitions. Whichever definition was used, about 5%-6% of intubations carried out in operating rooms could be characterised as having moderate to severe difficulty. I do not need to discuss the various circumstances or anatomical attributes which could give rise to a difficult airway in a patient; it is sufficient to note that among the medical professionals who involved themselves in airways management there were those who took a particular interest in difficult airways. In the United Kingdom that interest was often manifested by membership of the Difficult Airways Society, which is a specialist society of anaesthetists with (in 2010) about 2,500 members.
(ii) The laryngoscope
[12] Conventional laryngoscopes consist of two parts, the handle and the blade. The medical practitioner controls the laryngoscope by holding the handle in his left hand. The handle contains batteries to power an illumination device on the blade of the instrument. The blade of the instrument is inserted through the mouth. Its distal end is placed either in the vallecula or on the posterior surface of the epiglottis, as I have described. It is the means by which the practitioner applies force to lift the epiglottis. At the priority date there were two principal types of laryngoscope in general use. One had a curved blade and the other had a straight blade.
[13] The curved blade, which was used in most hospitals in the United Kingdom, was the Macintosh blade, which was inserted paraglossally in the right hand side of the patient's mouth and which had a flange to displace the tongue. Accordingly, the blade could then traverse the oral cavity in the midline and advance until the distal end of the blade was placed either in the vallecula or on the posterior of the epiglottis. There was some disagreement between the expert witnesses as to whether curved blades were widely used for direct elevation of the epiglottis (by lifting its posterior surface) as well as for indirect elevation in the vallecula; but nothing turns on that disagreement in this case. It was not disputed that the blades could be used in either way.
[14] The other principal type of laryngoscope had a straight blade, of which the Miller blade was commonly used. In the United Kingdom, straight blades were used predominantly in paediatric cases. Typically, straight blades have a semi-circular channel which protects the undersurface of the blade from intrusion by the patient's tongue and also provides access for the insertion of the endotracheal tube. They are inserted paraglossally. A laryngoscope with a straight blade is often used for direct elevation of...
To continue reading
Request your trial
-
Total Containbment Engineering Ltd V. Twma Group Limited
...Ltd [2005] RPC 9 (HL); British Celanese Ltd v Courtalds Ltd (1935) 52 RPC 171 (HL); Verathon Medical (Canada) Ulc v Aircraft Medical Ltd [2011] CSOH 19; Unilever plc v Schöller Lebensmittel GmbH & Co KG [1988] FSR 596; and Conoco Speciality Products (Inc.) v Merpro Montassa Ltd 1992 SLT 444......
-
Merck Sharp & Dohme Group v Hovid Berhad, 21-08-2019
...4 at [54] is that which is adopted in the United Kingdom. The Scottish case of Verathon Medical (Canada) ulc v Aircraft Medical Limited [2011] CSOH 19 (“Verathon”) dealt with a patent of intubation instruments. What patentee purported to be the inventive concept was the attachment of a came......
-
Verathon Medical (canada) Ulc V. Aircraft Medical Limited
...et Higgins; Maclay Murray & Spens LLP Defender: Lake QC; DLA Piper Scotland LLP 30 March 2011 [1] On 1 February 2011 I issued an opinion ([2011] CSOH 19), which has given rise to these motions for expenses. In that opinion I refused the pursuers' application to amend their patent, assoilzie......
-
Scots Law News
...may not have been too happy with the outcome). The patent infringement case of Verathon Medical (Canada) Ltd v Aircraft Medical Ltd [2011] CSOH 19 was concerned with intubation devices such as laryngoscopes. After detailed analysis of both the invention and the relevant law, Lord Hodge held......