Observations of Vital Signs
Measurement of a patient’s vital signs should be undertaken postoperatively at least every 1 to 2 hours for the first 12 hours, reducing to every 4 to 6 thereafter until discharge. Changes in such parameters may indicate the presence of active bleeding (reduced blood pressure and increased pulse), imminent bleeding (high blood pressure), infection (increased pulse, temperature, or respiratory rate), pulmonary embolus (increased respiratory rate and pulse), or postoperative pain (increased blood pressure, pulse, or respiratory rate).
20.3 Prevention of Postoperative Bleeding
Retrobulbar hemorrhage is the most feared complication of orbital surgery. Accumulation of blood in the confined space of the orbit can rapidly compress the optic nerve resulting in optic neuropathy that may lead to irreversible visual loss. This is sometimes referred to as orbital compartment syndrome (OCS). Endoscopic endonasal orbital procedures that create a communication between the orbit and the sinonasal cavity (such as orbital decompression) carry a very low risk of confined retrobulbar hemorrhage or compartment syndrome, as blood can exit the orbit. However, there are rare reports of compartment syndrome developing in an unconnected orbital compartment despite a sinonasal–orbital connection having been made. 1 A transorbital approach to lesions that leave the orbital bones intact carries a small but significant risk of postoperative hemorrhage, particularly if the surgery was undertaken for a vascular lesion, or if the patient is taking anticoagulant medications or has a pre-existent bleeding diathesis.
Meticulous intraoperative hemostasis minimizes the risk of retrobulbar hemorrhage. The following postoperative measures should be considered.
20.3.1 Blood Pressure Control
Regular monitoring of blood pressure is essential in the first 24 hours postsurgery. Raised blood pressure increases the risk of postoperative bleeding. Patients should continue antihypertensive medication on the day of surgery and during the perioperative period. Pain may be accompanied by increases in blood pressure and so should be managed with regular analgesia. Activities that acutely increase intracranial pressure, orbital pressure, and blood pressure such as strenuous exercise, lifting, stooping over, and nose blowing should be avoided in the first 2 weeks of postorbital surgery.
20.3.2 Pad and Dressings
The utility of postoperative ocular padding and pressure dressing has been debated in the orbital surgery literature. Although pressure dressings may assist hemostasis, they may also potentially increase the pressure of a developing hemorrhage on the optic nerve (exacerbating the tight orbit) and possibly conceal reducing vision and increasing proptosis. If a pad and/or pressure dressing is used, vision must be checked on emergence from anesthetic and every 2 to 4 hours for the first 24 hours. The patient must also be advised to immediately report increased pain or reduced vision. It is the authors’ preference to use a lightly taped double pad to put gentle pressure on the orbit for 12 to 24 hours after transorbital procedures and no pad after endoscopic orbital procedures.
20.3.3 Surgical Drains
Increases in orbital volume by as little as 7 mL can cause significant acute changes to the optic disc morphology. 2 Drain collection volumes over 70 mL of serosanguineous fluid have been reported. 3 Despite this, most orbital surgeons use drains rarely, reserving them for prolonged cases or cases involving excision or debulking of vascular lesions. If used, a fine suction drain is generally preferred and this can almost always be removed after a period of 12 to 24 hours without fluid collection.
20.3.4 Hot Drinks
It has been common practice to advise patients to avoid hot drinks and baths in the first postoperative week. Hot drinks and baths may increase peripheral vasodilation. However, there is no evidence to support this practice and unless a patient is at very high risk of bleeding, these measures are probably not required.
20.3.5 Recommencing Anticoagulation
Decisions on stopping and restarting anticoagulant and antiplatelet medications must be individualized and discussed with the patient’s physicians. The risk of severe hemorrhage (requiring transfusion or surgical intervention) in patients undergoing endoscopic dacryocystorhinostomy (DCR) is 0.6%. 4 The risk in orbital surgery has not been reported, but would likely vary according to the nature of the procedure and the lesion. In general, patients with a high risk of cerebral or cardiac vascular occlusion should have anticoagulation restarted immediately postoperatively or not stopped at all, while those at low risk might restart at 5 days postoperative when the primary clot is more secure.
20.3.6 Detection and Management of Orbital Hemorrhage
Postoperative OCS is a surgical emergency. It can occur in the early postoperative period particularly if intraoperative hemostasis was not achieved or if there is a marked increase in blood pressure. Rarely, it can occur several days postoperatively from clot dissolution (usually in patients on aspirin). Vision can be irreversibly lost within 2 hours of the onset of hemorrhage. 5 It is recognized by the symptoms and signs summarized in ▶ Table 20.1. The management of OCS necessitates an immediate return to the operation theater and blood pressure control with head elevation until surgery commences.
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Decompression of the orbit should be performed immediately upon recognition of the problem, despite the fact that there are reports of it being beneficial up to 48 hours posthemorrhage. 6 Decompression can be achieved via a lateral canthotomy and inferior ± superior canthal tendon cantholysis, orbital floor fracture, or medial orbital wall decompression. 7, 8, 9 If theater space is not available, both lateral canthotomy and orbital floor decompression can be conducted at the bedside under local anesthetic. ▶ Table 20.2 demonstrates the technique for performing a lateral canthotomy.
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20.3.7 Detection and Management of Epistaxis
A minor amount of anterior and posterior nasal blood loss is expected postsurgery. The use of a nasal bolster to catch anterior bleeding is recommended. Mild to moderate epistaxis usually settles with conservative measures including blood pressure control, analgesia, head elevation (without neck hyperextension), icepacks on the neck and bridge of the nose, and topical nasal vasoconstrictor sprays. If bleeding persists, packing may be required. If necessary, this should be performed, preferably under endoscopic guidance to avoid trauma to the recently operated site. If bleeding persists despite these measures, a return to theater may be required for sphenopalatine, or anterior ethmoidal artery ligation.
20.4 Control of Periorbital Bruising and Swelling
20.4.1 Head Elevation and Mobilization
Postoperative head elevation reduces periocular edema, through gravity-assisted venous drainage. A higher sitting angle would be expected to be more effective. One study has reported less facial edema in patients nursed at 90 degrees than those at 30 degrees. 10, 11 Patients often find it uncomfortable to sit upright in the postoperative period and so we usually recommend that the patient be nursed at the highest comfortable angle, which is typically around 45 degrees. Gentle, early mobilization is to be encouraged to minimize the risk of deep vein thrombosis and pulmonary embolus, and to reduce periocular swelling.
20.4.2 Icepacks
The judicious use of icepacks acutely reduces swelling through local vasoconstriction, although there is no evidence that this alters the postoperative recovery time course.
20.4.3 Postoperative Corticosteroids
Oral and topical corticosteroids are widely used after endoscopic endonasal surgery, as they may reduce swelling and promote wound healing. Despite this, there is limited evidence that administration of intraoperative or postoperative corticosteroids reduces postoperative swelling following orbital surgery and no evidence of a benefit to outcomes. 12 Despite the absence of evidence, the administration of systemic steroids is recommended in patients undergoing orbital surgery with underlying inflammatory conditions such as thyroid eye disease and granulomatosis with polyangiitis.
20.5 Antibiotics and Infection Prevention
Orbital surgery can be divided into procedures that are confined to the orbit and those that connect the orbit to the sinonasal cavity, such as medial wall decompression, fracture repairs, and endonasal endoscopic approaches to the orbit. Theoretically, the former group is considered clean surgery, while the latter can be classified as clean-contaminated due to the extensive colonization of the nasal cavity by microbial organisms. Interestingly, the risk of infection does not seem to be higher in the latter group, at least anecdotally. Postoperative antibiotics are widely used in orbital surgery although there is currently no evidence to support this practice. Studies of antibiotics postorbital floor fracture repair did not find a significant risk of infection in patients not receiving antibiotics or those receiving them for 24 hours postoperatively. It should be noted, however, that all patients in these studies did receive preoperative antibiotics. 13, 14
Postoperative orbital inflammation occasionally does not settle despite antibiotic treatment for presumed infection. The possibility of a retained foreign body, such as gauze, neuropathies, or organic matter from traumatic injury, must be considered. The foreign body may be identified on fine-cut MRI (magnetic resonance imaging) or computed tomography (CT) scanning. Surgical exploration and foreign body excision may be required. Bone wax can also cause persistent giant cell granulomatosis, which may require surgical removal. 15
20.5.1 Detection and Management of Orbital Infection
▶ Table 20.3 summarizes the clinical and laboratory findings associated with orbital infection. Orbital infection is treated with intravenous antibiotics and may require incision and curettage or debriding of purulent collections.
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20.6 Prevention of Orbital Emphysema
Orbital emphysema can complicate surgery that connects the orbit to the sinonasal cavity ( ▶ Fig. 20.1). This typically occurs if the patient blows his or her nose, but a “ball valve” phenomenon can occur with normal respiratory pressure. Therefore, all patients with known or possible sino-orbital communication should be instructed not to blow their nose for 2 weeks postoperatively. Orbital emphysema typically presents with rapid- or even sudden-onset proptosis and lid swelling, diplopia, crepitus, and raised intraocular pressure. It is typically a self-limiting condition that can be treated conservatively with advice to avoid nose blowing. However, very occasionally it can result in optic nerve compression and visual loss. For this reason, 15- to 30-minute visual observations should be performed in the first 24 hours after its occurrence. Vision-threatening orbital emphysema can be treated with surgical drainage, aspiration of trapped air, and palmar pressure on the globe. 16, 17, 18, 19, 20
Fig. 20.1 Orbital emphysema. (a) Clinical. (b) CT (computed tomography) scan.