Local anaesthesia for vitreoretinal surgery: an audit of patient and surgical experience

Analysis of Operational Efficiency and Cost Differences between Local and General Anesthesia for Vitreoretinal Surgery

There has been a growing trend of using local anesthesia (LA) compared to general anesthesia (GA) over the last two decades in VR surgery. We aim to answer the following question: what is the institutional benefit of LA versus GA use in operation-room time, anesthesia duration, earlier discharge from an outpatient surgery facility, and the estimated cost savings? We conducted a retrospective analysis of 1476 eyes that underwent vitreoretinal surgery over a 6-year period from a single site; 61.8% of patients received GA and 38.2% received LA for VR surgery. Anesthesia, surgical, and recovery times were significantly shorter with LA (100.49, 66.47, 66.47 mins) vs. GA (145.53, 100.14, 75.08 mins). Anesthesia, surgical, and recovery costs were significantly lower for eyes that received LA, with an estimated adjusted cost reduction of USD 1516 per surgery using LA instead of GA. Use of LA for vitreoretinal surgery is associated with better operational efficiency, earlier patient discharge, and significant cost reduction.

Efficacy and safety of trans-sub-Tenon's retrobulbar anesthesia for pars plana vitrectomy: a randomized trial

AIM

To compare the efficacy and safety of trans-sub-Tenon's ciliary nerve block anesthesia and transcutaneous retrobulbar anesthesia in patients undergoing pars plana vitrectomy (PPV).

METHODS

A prospective, randomized, double-blinded clinical trial was conducted at Zhongda Hospital, Affiliated with Southeast University, from February 2021 to October 2021. Patients undergoing PPV were randomly allocated into two groups: the trans-sub-Tenon's anesthesia group (ST group) and the retrobulbar anesthesia group (RB group) in the ratio of 1:1. The ST group received 2 ml ropivacaine through the Tenon capsule to the retrobulbar space, while the RB group received 2 ml ropivacaine via transcutaneous retrobulbar injection. Visual analog score (VAS) was used to evaluate pain during the whole process, including during anesthesia implementation, intraoperatively and on the first day after the operation. Movement evaluation (Brahma scores) and anesthesia-related complications were also noted.

RESULTS

Finally, a total of 120 patients were included in the study (60 in the ST group and 60 in the RB group). There were no significant differences in baseline patient characteristics or surgical features between the two groups. The VAS pain scores for anesthesia implementation were 0.52 ± 0.47 in the ST group and 1.83 ± 0.87 in the RB group (P < 0.001). The VAS scores during the operation were 0.53 ± 0.49 in the ST group and 1.48 ± 1.02 in the RB group (P < 0.001) and those on the first day after the operation were 0.37 ± 0.38 in the ST group and 0.81 ± 0.80 in the RB group (P = 0.002). No patients required supplemental intravenous anesthesia intraoperatively. The Brahma movement scores were 0.70 ± 1.64 in the ST group (scores ranging from 0 to 8) and 2.38 ± 3.15 in the RB group (ranging from 0 to 12) (P = 0.001). Forty-two patients in each group received laser photocoagulation during surgery. Fifteen patients (36%) in the ST group could not see the flashes of the laser, compared to 8 patients (19%) in the RB group (P = 0.087). No serious sight-threatening or life-threatening complications related to anesthesia were observed in either group.

CONCLUSIONS

For PPV, trans-sub-Tenon's ciliary nerve block anesthesia was more effective in controlling pain than transcutaneous retrobulbar anesthesia during the whole surgery process, including during anesthesia implementation, intraoperatively and on the first day after the operation. Additionally, it could achieve better effect of akinesia and was relatively safe. Trans-sub-Tenon's anesthesia could be considered an alternative form of local anesthesia during vitreoretinal procedures.

TRIAL REGISTRATION

The study protocol has been registered at ChiCTR.org.cn on February 2021 under the number ChiCTR2100043109 .

Bupivacaine-lidocaine versus Ropivacaine-lidocaine Retrobulbar Anesthesia in Vitreoretinal Surgery

Purpose: To compare efficacies of bupivacaine-lidocaine and ropivacaine-lidocaine mixtures in terms of inducing retrobulbar anesthesia during vitrectomy.Methods: Sixty patients who underwent retrobulbar anesthesia during vitrectomy were divided into two groups. Patients in group 1 received a mixture of bupivacaine and lidocaine (n = 30); patients in group 2 received a mixture of ropivacaine and lidocaine (n = 30). The effects of the two combinations were retrospectively compared and analyzed. The onset times of analgesia and akinesia were measured. Two hours after surgery, sensory blockade was assessed by touching the corneas with cotton swabs and by communicating with patients. Ocular movement was evaluated in four gaze direction quadrants. A 10-point visual analog pain scale was used to assess pain during and 2 hours after surgery. Intra- and postoperative complications were recorded.Results: The mean analgesia onset times in groups 1 and 2 were 94.62 ± 28.87 and 92.32 ± 35.53 seconds, respectively (p = 0.071); the mean akinesia onset times were 147.89 ± 59.35 and 132.57 ± 76.38 seconds (p = 0.223), respectively. Patients in group 2 reported significantly less postoperative pain and exhibited less postoperative ocular movement, compared with patients in group 1 (both p = 0.002). One patient in group 1 experienced respiratory depression after retrobulbar blockade.Conclusions: When retrobulbar anesthesia is required during vitrectomy, a ropivacaine-lidocaine mixture and a bupivacaine-lidocaine mixture induce anesthesia with similar rapidity. However, the ropivacaine-lidocaine mixture is safer and affords better-quality intra- and postoperative anesthesia.

Pain during pars plana vitrectomy following sub-Tenon versus peribulbar anesthesia: A randomized trial

Purpose

To compare pain during pars plana vitrectomy (PPV) following topical lidocaine jelly and sub-Tenon anesthesia versus peribulbar anesthesia.

Methods

Prospective, single-center, randomized study. Patients scheduled for PPV for macular hole (MH) or epiretinal membrane (ERM) at the Retina and Vitreous Section of the Department of Ophthalmology, Ribeirão Preto Medical School, University of São Paulo were randomly assigned to one of two groups in a 1:1 allocation ratio. Patients assigned to Group ST received topical anesthesia with 2% lidocaine jelly followed by sub-Tenon anesthesia with 2–4 ml of 1% ropivacaine. Patients assigned to PB received peribulbar anesthesia with 4–6 ml of 1% ropivacaine. After PPV, patients in both groups were asked to rate the level of pain they felt during the entire procedure (including anesthesia administration and PPV) by pointing at a 0–100 Visual Analogue Pain Scale (VAS). Data regarding demographics, patient characteristics and surgical features were also collected.

Results

Fifty-four patients were enrolled in the study (26 in Group ST and 28 in Group PB). Baseline characteristics, including age, gender, and presence of comorbidities, were similar in both groups. The surgery performed was PPV alone in 10 and 14 patients in the ST and PB groups, respectively, and combined phacoemulsification and PPV in 16 and 14 patients in the ST and PB groups, respectively (p = 0.39, Pearson). Surgery duration (mean ± SD minutes) was similar in the two groups (62 ± 12 for ST and 70 ± 20 for PB, p = 0.09, t-Test). No patients needed supplemental topical or intravenous anesthesia during surgery. No sight- or life-threatening complication was observed in either group. VAS score was significantly lower in the ST compared to the PB group (median (interquartile range) was 1 (2.25–0) in the ST group compared to 11.5 (29.75–5) in the PB group, p< 0.0001, Wilcoxon).

Conclusion

In this study of patients who underwent PPV for MH or ERM, topical followed by sub-Tenon anesthesia was more effective in controlling pain during the whole vitrectomy procedure than peribulbar anesthesia. Compared to peribulbar anesthesia which is administered with a sharp needle, sub-Tenon anesthesia administered with a blunt cannula may be associated with a reduced risk of such adverse events as globe perforation, retrobulbar hemorrhage, and inadvertent injection of anesthesia into the optic nerve sheath.

Anesthesia for pars plana vitrectomy with insulin needle, is it possible?

Peribulbar block is commonly used for ocular posterior segment surgery. This work aimed to compare the efficacy of using 12.5 mm to 25 mm standard needle length in performing single injection peribulbar block for retinal surgery. Peribulbar block was performed in 120 patients using either standard 25 mm or 12.5 mm 30 G needle (insulin needle). While applying digital pressure around the needle hub, 8–10 mL of local anesthetic are injected. Ocular movement was assessed at 5 and 10 min using simple akinesia score (0–8). If after 10 min score was >1, supplementary injection was given. Visual analogue scale (0–10) was used at the end of the procedure to assess surgeons' satisfaction and patients' intraoperative pain. No differences in akinesia score at 5 & 10 min (P = 0.34 and 0.36, resp.). Initial volume injected was comparable between groups (P = 0.31), however total volume of local anesthesia and supplementary injections were significantly higher in 12.5 mm group (P = 0.03 and 0.01, resp.). No difference as regard surgeons' satisfaction and patients' intraoperative pain (P = 1.0 and 0.18, resp.). Peribulbar block with 12.5 mm needle together with digital compression is a suitable alternative to the standard block with 25 mm needle length for retinal surgery.

Superficial extraconal blockade for vitreoretinal surgery

Context:

Needle length plays an important role for the success of ophthalmic block. The standard practice is to use 25 mm needles length; however, unnecessarily long needles may increase the risk of complications especially in the presence of staphyloma or previous scleral buckle.

Aims:

This work was designed to compare the efficacy of using 15 and 25 mm needle in performing extraconal block for patients undergoing vitreoretinal surgery.

Settings and Design:

Prospective randomized double blinded study.

Materials and Methods:

A total of 120 patients were enrolled in this study and were divided in two groups. In group (1) extraconal block was performed using 25 mm needle, while in group (2) 15 mm needle was used. After primary injection, assessment of the block was done by an anesthesiologist who was unaware of the needle used. If satisfactory akinesia was not achieved a supplementation was provided. At the end of the procedures, patients and surgeons were asked to assess their pain and satisfaction with the anesthetic technique.

Statistical Analysis used:

The sample size calculation using N-Quary version 4. Numerical and categorical data were analyzed using an independent sample, a two-tailed t-test, and chi-square test, respectively.

Results:

The volume of primary injectable was significantly higher in group 2. The two groups were comparable as regards total volume of local anesthetic, supplementation rate, akinesia, pain score, and surgeon satisfaction.

Conclusions:

Using 15 mm needle length to perform extraconal blockade for posterior segment procedures is equally effective to 25 mm needle.

Diplopia and strabismus following ocular surgeries

Postoperative diplopia and strabismus may result from a variety of ocular surgical procedures. Common underlying mechanisms include sensory disturbance, scarring, direct extraocular muscle injury, myotoxicity from injections of local anesthesia or antibiotics, and malpositioning of extraocular muscles by implant materials. The most common patterns are vertical and horizontal motility disturbance. Treatment options include prisms, botulinum, occlusion, or surgery.

Subjective visual perceptions during vitreoretinal surgery under local anaesthesia

PURPOSE

To evaluate the visual experiences of patients during vitreoretinal surgery under local anaesthesia (LA).

METHODS

Prospective questionnaire survey of 80 patients within 30 min of completion of vitreoretinal surgery under LA. Preoperative visual acuity, surgical procedure and its duration, efficacy of the local block, as well as intraoperative perceptions of flashes, colours, movements, and seeing instruments were documented.

RESULTS

A sub-Tenon's block was performed in 62/80 (77.5%) and a peribulbar block in the remainder. Overall, 72 (90%) of patients perceived light at some stage during their surgery. Of these, 51 (70.83%) observed movements, 45 (62.5%) saw colours, 38 (52.77%) saw instruments, and 24 (33.33%) saw flashes. The commonest observations were colourful swirls, black pipes, and the colour red. Most patients found these experiences pleasant or bearable; two found them frightening, and four would like to have been warned preoperatively about them. Preoperative visual acuity, diagnosis, gender of the patient, degree of akinesia, and the duration of surgery did not associate with visual perceptions. Logistic regression analysis showed that younger people were more likely to experience flashing lights (P=0.03) and to see instruments (P=0.04), patients having a sub-Tenon's block to perceive light (P=0.005), and those who did not receive awake sedation were more likely to see instruments (P=0.04).

CONCLUSIONS

Visual experiences are common during vitreoretinal surgery undertaken under LA. Where appropriate, patients should be forewarned about these experiences and reassured that they are not normally frightening.

Feasibility of day-case vitreoretinal surgery

PURPOSE

The indications for vitreoretinal (VR) surgery are increasing as equipment and techniques available improve. In order to decrease demand on limited health resources, day-case surgery would be beneficial in many cases. This study combines a retrospective and prospective arm to examine the feasibility and safety of routine day-case VR surgery.

METHODS

One hundred consecutive patients (50 retrospective and 50 prospective) undergoing VR surgery within the Royal Berkshire NHS trust were included. The retrospective arm aimed to identify the frequency and type of acute ophthalmic or medical intervention during postop overnight stay and the results were used to alter management in the prospective group. The prospective group consisted of patients undergoing a mixture of overnight stay and day-case surgery. All patients in the prospective group had routine subtenon marcaine anaesthesia together with prophylactic pre-operative intravenous acetazolamide. Patients deemed fit postoperatively were offered overnight ward discharge, with obligatory next-day review.

RESULTS

In the retrospective arm, 56% required oral nonsteroidal analgesia on the day of surgery and one patient required narcotic analgesia. Twenty-two per cent patients required intraocular pressure (IOP) control on the day of surgery and one patient required medical intervention in the form of urinary catheterisation. Nineteen patients required intervention on next-day review. In the prospective arm, 86% preferred day case and were suitable, 6% were suitable for day-case but preferred overnight stay and 8% were deemed not fit for discharge. No patient required narcotic analgesics. No patient discharged returned as a casualty overnight. Only one patient required topical beta-blocker for the control of IOP on next-day review.

CONCLUSIONS

These data suggest that many patients who are hospitalised overnight for VR surgery could be safely treated as day cases. Such a shift in the pattern of care for VR surgery could provide a significant improvement in health-care efficiency and minimise patient inconvenience.

Ophthalmic regional anaesthesia

PURPOSE OF REVIEW

To summarize recent knowledge concerning ophthalmic regional anaesthesia.

RECENT FINDINGS

Ophthalmic regional anaesthesia has changed considerably over the past few years. Alternatives to retrobulbar anaesthesia have been proposed to reduce the number of complications without detriment to efficiency. Finally new local anaesthetics have been adopted and the indications have broadened, especially in vitroretineal surgery.

SUMMARY

New developments in ophthalmic regional anaesthesia are presented in this review. Different methods, indications and side effects are described in order to facilitate the clinician's choice, without any claim to single out an ideal technique.