Simple Outpatient Postoperative Analgesia Using an Orbital CatheterAfter Enucleation

Objective  To evaluate an indwelling orbital catheter, placed at enucleation, forrepeatable delivery of local anesthetic on an outpatient basis.

Methods  A retrospective, noncomparative, case series medical record review wasperformed of patients undergoing enucleation and receiving an indwelling orbitalpain-control catheter at surgery by us from January 1, 1998, through December31, 2001. Medical records were reviewed for hospitalization status postoperatively.Medical records of those patients treated on an outpatient basis were reviewedfor patient and family comments about ease of use of the pain-control catheterand the degree of pain control and for any complications associated with catheteruse. The main outcome measures included documented patient and family commentsand physician medical record notes about catheter use and complications.

Results  Of the 85 patients, 67 were treated on an outpatient basis. The other18 patients required a postoperative hospital admission for unassociated medicalproblems. Of the 67 patients, 58 (87%) reported using the catheter at homeat least once. Of these 58 patients, 10 reported mild discomfort with catheteruse, but in no case did the patient discontinue catheter use because of discomfort.All patients using the catheter reported pain relief lasting from 1½to 4 hours. No postoperative complications associated with catheter placementwere observed.

Conclusion  The orbital pain-control catheter allows a caregiver to easily and repeatedlydeliver local anesthetic to the operative site following enucleation, resultingin effective postoperative analgesia while the patient recovers at home.

Pain is the most common reason for an unplanned hospital admission afterambulatory surgery and, thus, effective outpatient surgery requires adequatepostoperative pain control.¹ Enucleation canresult in severe postoperative pain, requiring either outpatient oral narcoticsor inpatient analgesia. Uncontrolled pain can lead to nausea, vomiting, crying,and generalized restlessness, all resulting in an increased risk of postoperativehemorrhage. Enucleation is most often performed under general anesthesia.A postoperative retrobulbar injection of local anesthetic provides effective,but temporary, relief. An orbital epidural catheter attached to a computerizedambulatory patient-controlled analgesia (PCA) bupivacaine hydrochloride pumphas been described for patients undergoing orbital implantation, allowingimproved postoperative pain control on an outpatient basis.² Thiscatheter decreased postoperative pain and was safe. We have developed a simplifiedindwelling orbital catheter, placed during enucleation for the delivery oflocal anesthetics without the use of a PCA pump, to assist in postoperativepain control. This study evaluates the use of this pain-control catheter onan outpatient basis by patients undergoing enucleation.

The Johns Hopkins University School of Medicine Joint Committee on ClinicalInvestigation exempted the study from review, believing it qualified for exemption4 under Department of Health and Human Services regulations 45CFR46.101(b).The medical records of 85 consecutive patients undergoing enucleation by us(S.L.M. and N.T.I.) from January 1, 1998, through December 31, 2001, werestudied retrospectively. All 85 patients received an orbital pain-controlcatheter during enucleation. The catheter was prepared by removing the butterflyneedle from a commercially available 20-cm precapped intravenous catheter(Figure 1). A 4-0 nylon suture wastied around the catheter 2 to 3 cm from the cut end. After removal of theglobe, the needle on the nylon suture was passed from inside the orbit outthrough the skin (Figure 2). Thecut end of the catheter was positioned in the posterior orbit under directvisualization (Figure 3). The catheterwas temporarily secured in place until completion of the surgery by hanginga clamp from the suture to apply tension. The remaining steps of the enucleationwere performed as usual. The conjunctiva was closed, with the catheter exitinglaterally (Figure 4). The cappedend of the catheter was taped to the anterior surface of the patch, and thesuture was cut at the skin (Figure 5).Patients treated on an outpatient basis were sent home with two 10-mL syringesof a 50:50 mixture of 0.75% bupivacaine hydrochloride and 4% lidocaine hydrochloride.Before discharge, the caregiver was given a demonstration of the use of thecatheter by the operating surgeons (S.L.M. and N.T.I.), as well as writteninstructions for catheter use. The caregivers were instructed to slowly injectup to 2 mL of the anesthetic every 4 hours as needed for pain. The patientswere also given a prescription for a combination of acetaminophen, 500 mg,and oxycodone hydrochloride, 5 mg. Patients returned in 2 to 3 days for patchand catheter removal. The temporary nylon fixation suture is removed as thecatheter is removed.

Of the 85 patients undergoing enucleation during the 3-year study period,67 were treated on an outpatient basis. Eighteen patients were admitted postoperativelyfor medical conditions unrelated to pain control, including hypotension, hypoxia,hemoptysis, and hypokalemia. Of the 67 outpatients, 34 were male and 33 werefemale. The mean patient age was 51 years (range, 2-91 years). Patients underwentenucleation for blindness and pain (n = 51), uveal melanoma (n = 24), a rupturedglobe (n = 7), and endophthalmitis (n = 3). Sixty-one patients received high-densityporous polyethylene implants (MEDPOR; Porex Surgical, Inc, Newnan, Ga) (20-mmsphere, 28 patients; 18-mm sphere, 1 patient; 16-mm sphere, 1 patient; 20-mmMCOI, 25 patients; and 5-mL COI, 6 patients). Six patients received 20-mmplastic spherical implants.

Of the 67 outpatients, 58 (87%) reported using the pain-control catheterat home at least once. Of the 9 patients who did not use the catheter, 7 reportedhaving no postoperative pain requiring catheter use. One patient did not usethe catheter because there was no one "qualified to administer the anesthetic"in his nursing home. One patient was a 2-year-old child whose parent requestedthat the catheter be taped over because she was afraid her son would dislodgeit. No patient or caregiver reported any difficulty associated with catheteruse. All patients who used the catheter reported relief of pain lasting from1½ to 4 hours. Thirteen patients reported using all 10 doses of anesthetic,and 4 of these patients specifically wanted access to more doses during the3-day postoperative period.

Of the 58 patients, 10 (17%) reported mild discomfort with catheteruse, ranging from "feeling funny" to "slight burning." No patients discontinuedcatheter use secondary to discomfort. Of the 5 patients who reported postoperativenausea, only 1 specifically associated the nausea with catheter use. Thispatient also continued to use the catheter, despite the nausea, because ofthe pain relief. No complications, including postoperative infection, retrobulbarhemorrhage, or toxic adverse effects of bupivacaine, were observed. No problemswere encountered in removing the catheter.

More than 60% of all types of surgical procedures are performed in anambulatory setting,³ and this percentage iscertainly higher for the field of ophthalmology. Inadequate postoperativepain relief can result in crying and restlessness, leading to hematoma formation,increased pain, delayed wound healing, and prolonged recovery. In addition,poor control of postoperative pain can precipitate or increase the durationof the hospital stay, increase health care costs, and reduce patient satisfaction.While opioid analgesics are the mainstay of pain control in the early postoperativeperiod, their use can be associated with nausea, vomiting, sedation, ileus,and respiratory depression.⁴ Multimodal analgesia,using a combination of oral agents and a local anesthetic, is recognized asa superior postoperative analgesia vs any modality alone.⁵ Localanesthetic techniques can decrease the level of postoperative pain and reducethe requirement for opioids. Specifically, wound infiltration of local anestheticscan provide effective postoperative analgesia.^4-6

Enucleation is often performed under general anesthesia and can resultin significant postoperative pain.^7,8 Whilea retrobulbar injection of local anesthetic can provide effective relief ofpain postoperatively, the relief is only temporary. A safe and simple localanalgesic delivery system is needed to provide cost-effective pain reliefafter outpatient enucleation. We developed a pain-control catheter, placedduring enucleation under direct visualization, that allows a patient's caregiverto administer a local anesthetic at home as needed for pain control afterenucleation. We found that the catheter provided relief from postoperativepain in all patients who used it, with 17% reporting mild discomfort on injectionof the local anesthetic, which did not limit catheter use. We did not observeany other complication from catheter placement or use. A larger multicentertrial could be performed to further document the safety of this approach.

While indwelling retrobulbar catheters for the delivery of medicationare not novel to ophthalmology or enucleation, the use of such a catheterto provide postoperative pain control after ambulatory surgery is a recentinnovation. The first description of a retrobulbar catheter left in placefor 2 to 3 days following enucleation was by Scheie⁹ in1956. Several reports describe the inpatient use of retrobulbar cathetersfor repeated injections of local anesthetics to control intraoperative andpostoperative pain associated with intraocular surgery^10-15 andenucleation.¹⁶ Lincoff and colleagues^17,18 described a retained retrobulbarcatheter for the administration of medication for macular degeneration, requiringpatients to return for injections 6 days a week. None of these reports describehome use of an indwelling orbital catheter.

Loss of an eye can require significant emotional adjustment,^19,20 and postoperative recovery in a comfortableenvironment surrounded by a familiar support structure is ideal. Fezza etal² described a significant improvement inpostoperative pain control following enucleation, allowing the patient torecover at home. In their study, an epidural catheter was placed in the lateralorbital space, transcutaneously, on completion of the surgery. The catheterwas connected to a bupivacaine PCA pump delivering a continuous infusion onan outpatient basis and allowing the patient to administer boluses of bupivacaineas needed. A home health care nurse visited daily to check the functioningof the pump. Of the patients in the study, 88.2% reported complete or partialpain relief, with only 11.8% reporting severe pain without relief from theorbital pump. The low complication rate included 1 retrobulbar hemorrhageon placement of the catheter and 4 catheters that had to be removed, replaced,or repositioned because of obstruction. No toxic adverse effects from bupivacainewere observed.

Our pain-control catheter has several advantages over that describedby Fezza et al.² First, our catheter is placedunder direct visualization during the enucleation after removal of the eye.This essentially eliminates the risk of retrobulbar hemorrhage from catheterplacement and ensures that the catheter is not in the intravascular space,minimizing the risk of toxic effects from bupivacaine. Second, our catheterlumen is larger than that of the epidural catheter used by Fezza et al, andwe had no cases of catheter obstruction. One potential disadvantage of a largercatheter lumen is the potential rapidity with which the local anesthetic canbe delivered. All caregivers were instructed on the importance of a slow injection,but the potential for rapid tissue expansion may explain the mild discomforton anesthetic injection experienced by some patients in our study. All ofour patients reported pain relief, in contrast to those using the catheterdescribed by Fezza et al, for which 12% of patients reported severe pain withoutrelief from the pump. A third advantage of our catheter is the reduced costand simplicity. No PCA pump or home health care nursing visits were required.All caregivers found the catheter simple and easy to use with minimal instruction.

A significant difference between the PCA pump–linked catheterand our simplified catheter is the use of continuous infusion.² Continuousinfusion of bupivacaine has the potential advantage of providing continuousuninterrupted analgesia and minimizes the discomfort of boluses. However,continuous infusion also runs the risk of treating patients without pain,and we found that 10% (7/67) of our patients did not use the pain-controlcatheter even once because of lack of postoperative pain.

We have placed our pain-control catheter in patients undergoing eviscerationthrough an inferior fornix conjunctival incision for the peribulbar applicationof lidocaine-bupivacaine, and have found the pain control to be somewhat lesseffective (unpublished data, 1998-2001). This may be secondary to the increasedpain after evisceration compared with enucleation that others²¹ haveseen. However, it is also quite possible that the retrobulbar placement ofthe catheter described by Fezza et al² mayprovide better anesthesia during evisceration.

One potential long-term risk of the repeated application of a retrobulbaranesthetic by either catheter is myotoxicity of the anesthetic agent, reducingthe motility of the orbital implant.²² Thisrisk would be difficult to evaluate given the wide range of implant motilityfollowing enucleation.

In summary, we have designed an orbital catheter, placed during enucleationand used for the repeated delivery of a local anesthetic. Patients and caregivershave found the catheter easy to use and effective, with minimal adverse effects.We believe our catheter provides a welcome addition to oral narcotic analgesia,allowing enucleation procedures to be performed in an ambulatory setting,as dictated by economic pressure and patient preference.

Corresponding author: Shannath L. Merbs, MD, PhD, The Wilmer EyeInstitute, The Johns Hopkins University School of Medicine, 600 N Wolfe St,Maumenee 127, Baltimore, MD 21287 (e-mail: smerbs@jhmi.edu).

Submitted for publication May 1, 2003; final revision received August24, 2003; accepted September 15, 2003.

This study was supported by grant K08-EY00378 from the National EyeInstitute, Bethesda, Md (Dr Merbs); Research to Prevent Blindness, Inc, NewYork, NY (Dr Merbs); and the Niuta and Roy Titus Faculty Development Award(Dr Merbs).