Pressure sore on malar prominences by horseshoe headrest in prone position.
In recent times, concerns regarding postoperative visual loss in patients in the prone position are increasing among anaesthesiologists worldwide. As the necessary precautions regarding prevention of pressure on the eyeball in the prone position are undertaken, sometimes these can lead to undue pressure on the bony structures surrounding the eyeball. We report a case of pressure sores occurring in the prone position under general anaesthesia on the malar prominences of both the cheeks. The patient's consent was obtained for the publication of this history and the accompanying photo.
A 12-year-old, 40 kg, ASA I female patient was listed for posterior fixation of her atlanto-axial dislocation. After induction of general anaesthesia, the patient's eyes and face were padded with cotton and adequately secured with adhesive tape. The patient was then placed prone on a Wilson frame with her head supported on a padded horseshoe headrest. The head was maintained in a neutral forward position so as to prevent pressure on the eyeballs. Adequacy of padding and absence of pressure on the eyeballs were again checked before surgical draping.
The surgery lasted for approximately four hours and the intraoperative course was uneventful. When the patient was turned supine, the padding and adhesive tape were still in place. On removing them, pressure sores were seen on both malar prominences and upper margins of both eyes. There was no associated facial oedema. After reversal of neuromuscular blockade, the trachea was extubated. Pupils were equal in size and reacting to light and visual acuity in both the eyes was normal. Antibiotic ointment was applied locally over the pressure sores and healing took place over seven days. The patient was discharged from hospital on the 10th day.
[FIGURE 1 OMITTED]
Reported complications of the prone position are visual loss (1), corneal abrasion (2), conjunctival injuries (3) and facial swellings. In our case, there was no associated facial oedema and the protective padding on the eyes and face was intact. It seems that the pressure from the horseshoe on the bony structures surrounding the eyeballs resulted in pressure sores. This was probably missed in the initial stages of patient positioning due to concern regarding prevention of pressure on the eyeballs. Though the duration of surgery was not prolonged (four hours), it was sufficient to cause the pressure effect on the skin. Other factors such as the force exerted during surgical manipulation may have accounted for the pressure sore formation. However, it is unlikely as the force applied was for a short period of time. The neutral forward head position advised for prevention of central retinal artery occlusion (4) as used in our patient probably could have further increased the pressure on bony prominences. Members of the ASA task force on perioperative blindness agree that the use of the horseshoe rest increases the risk of ocular compression (4). Use of the three-pin head holder can ameliorate this problem as both pressure on the eyes and bony structures can be avoided. However there are also reports of ischaemic optic neuropathy following its use (5). Though the concerns regarding pressure on the eyeball in the prone position causing visual loss cannot be underestimated, emphasis must be laid on preventing extra pressure on the bony structures surrounding the eyeballs.
(1.) Roth S, Thisted RA, Erickson JP, Black S, Schreider BD. Eye injuries after non ocular surgery. A study of 60,965 anesthetics from 1988 to 1992. Anesthesiology 1996; 85:1020-1027.
(2.) Cucchiara R, Black S. Corneal abrasion during anesthesia and surgery. Anesthesiology 1988; 69: 978-979.
(3.) Biswas BK, Bithal PK, Dash M, Lamba NS, Biswas N. Keratoconjunctival injury in the prone position: A prospective study in neurosurgical patients. Eur J Anaesthesiol 2004; 21:663-665.
(4.) Practice Advisory for perioperative visual loss associated with spine surgery. A report by the American Society of Anesthesiologists task force on perioperative blindness. Anesthesiology 2006; 104:1319-1328.
(5.) Cheng MA, Sigurdson W, Tempelhoff R, Lauryssen Cl. Visual loss after spine surgery: A survey. Neurosurgery 2000; 46: 625-631.
P K. BITHAL
New Delhi, India