Respiratory arrest and convulsions after peribulbar anesthesia

Complication of Peribulbar Block: Brainstem Anaesthesia

Peribulbar block is used to obtain anaesthesia and akinesia of the eye by injecting a local anaesthetic around the musclecone. A patient scheduled for cataract surgery received peribulbar block with 6 mL of 2% lidocaine hydrochloride. Following the injection, confusion, hypotension and dilatation of the contralateral pupil rapidly progressed to loss of consciousness and respiratory arrest. The patient was intubated and mechanically ventilated for 30 min. The patient regained her consciousness, was extubated and transferred to the intensive care unit for further follow-up. Although brainstem anaesthesia because of peribulbar block is very rare, this procedure should be performed with complete monitorisation and resuscitation equipment.

Comparison of Peribulbar with Posterior Sub-Tenon's Anesthesia in Cataract Surgery Among Nigerians

Purpose:

To compare the akinetic and the analgesic effects of peribulbar and posterior sub-Tenon's anesthesia in patients undergoing cataract surgery.

Methods:

In a hospital-based randomized comparative interventional study, patients aged 50 years and above who underwent elective surgery for uncomplicated cataract were randomized to receive either peribulbar block or posterior sub-Tenon block. Pain during injection, surgery, and after surgery was assessed using numerical reporting scale (NRS). Limbal excursion was measured with a transparent meter rule.

Result:

A total of 152 eyes of 152 patients were studied. Peribulbar and sub-Tenon regional blocks provided comparable adequate akinesia (P = 0.06) and similar levels of analgesia (P = 0.10) during cataract surgery. Both techniques also provided similar levels of analgesia to the patient during injection and in the immediate postoperative period. Ninety-two percent of patients who had peribulbar and 97% of those who had sub-Tenon blocks reported either mild pain or no pain at all during surgery (P = 0.49). There was no report of severe pain in all patients during the stages of the surgery. Occurrence of chemosis and subconjunctival hemorrhage was more common in sub-Tenon than peribulbar anesthesia.

Conclusions:

This study shows that peribulbar and posterior sub-Tenon routes of administering anesthetic substances is comparable in providing adequate akinesia and analgesia for cataract surgery with minimal complications. Therefore, both techniques are effective and safe for cataract surgery among Nigerians.

Convulsions during cataract surgery under peribulbar anesthesia: a case report

INTRODUCTION

Locoregional anesthesia techniques are increasingly used for cataract surgery. From these techniques, peribulbar anesthesia has been very successful over the retrobulbar anesthesia seen its effectiveness and safety. However, peribulbar anesthesia is not without risk.

CASE PRESENTATION

A 70-year-old African man was scheduled for cataract surgery and lens implant for his right eye. His medical history included hypertension, diabetes mellitus and gall bladder surgery. There were no personal or family antecedents of allergy, epilepsy or taking food or toxic drug. No abnormalities were detected in his preoperative evaluation. In the operating room, standard monitoring was installed and a peripheral venous catheter 18g was inserted. Peribulbar anesthesia was realized with two injections in primary gaze position. The anesthetic mixture contained lidocaine 2% and bupivacaine 0.5%. The needle used was 25GA, 19mm, ¾ inch. The first injection was performed in his lower temporal peribulbar space with 5mL of mixture; the second injection was performed with 3mL of mixture in his upper nasal peribulbar space. These injections were performed after a negative aspiration test and followed by manual compression of his globe for 5 minutes. Five minutes after peribulbar anesthesia, his blood pressure increased to 209/115mmHg requiring three bolus of nicardipine (3.0mg) to reduce his blood pressure to 134/56mmHg. One minute after, he had generalized tonic-clonic seizures. Tracheal intubation was performed. His capillary blood glucose was 170mg/dL, axillary temperature was 36.5°C, and his serum electrolytes were normal. He recovered spontaneous ventilation 1.5 hours later. A neurological examination noted no deficit. Extubation was performed 15 minutes later without incident. A brain computed tomography and electroencephalogram were unremarkable. He was discharged on the second day and operated on 1 month later under general anesthesia.

CONCLUSIONS

Various serious complications can occur during locoregional anesthesia techniques in ophthalmic surgery. The mastering and perfecting of these techniques by practitioners and compliance with safety standards in anesthesia are the only way to guarantee the prevention of such complications.

Pulmonary oedema in a patient undergoing vitreo-retinal surgery under peribulbar block

A 42-year-old diabetic and hypertensive male with good effort tolerance was administered peribulbar block for vitreo-retinal surgery. Ten millilitres of an equal mixture of 2% lignocaine and 0.5% bupivacaine was administered for the block after ascertaining negative aspiration for blood. Inadequate akinesia of the eye necessitated further supplementation with 4 mL of local anaesthetic (LA) mixture. Thirty minutes later, the patient complained of uneasiness, respiratory distress and desaturated despite oxygen supplementation. He was found to be in pulmonary oedema. He subsequently developed a weak thready pulse, became unresponsive, apnoeic and had generalized tonic clonic convulsions. Immediately, atropine 0.6 mg, followed by midazolam, intubation, mechanical ventilation, morphine and furosemide, were administered intravenously. Spontaneous respiration returned in 20 minutes and he started responding to verbal commands 90 minutes later. He was weaned off the ventilator the next morning. There was no evidence of an ischemic myocardial event and non-contrast computerized tomography scan of the head was normal. The reversible cardiorespiratory arrest, associated convulsions and loss of consciousness were suggestive of LA toxicity. Pulmonary oedema manifesting as respiratory distress and desaturation can be the initial manifestation of LA toxicity in patients with pre-existing cardiovascular disease undergoing eye surgery under peribulbar block.

Systemic Adverse Events: A Comparison between Topical and Peribulbar Anaesthesia in Cataract Surgery

AIMS

To evaluate the safety of topical anaesthesia (TA) versus peribulbar anaesthesia (PBA) in patients undergoing routine cataract surgery on the basis of systemic adverse events.

METHODS

In this retrospective study, a total of 2,020 consecutive cases of cataract surgery performed by one surgeon on 1,621 patients with PBA (n = 1,010; between 1998-1999) or TA (n = 1,010; between 1999-2001) were evaluated on the basis of intra-operative and early postoperative adverse events requiring medical intervention.

RESULTS

The rate of pre-existing risk factors in patients undergoing cataract surgery is high (97%). Complications are significantly less frequent in TA than in PBA in the intra-operative (p < 0.001) and postoperative (p = 0.022) courses. The incidence of intra-operative complications is higher in elderly patients (>or=65 years of age) than in younger patients (p < 0.001).

CONCLUSION

The results from the present study indicate that intra-operative complications are less likely in patients that receive TA, suggesting the use of TA for routine cataract surgery both in young patients and particularly in elderly patients when there are no contraindications in the individual case.

Preemptive sub-Tenon's anesthesia for pars plana vitrectomy under general anesthesia: is it effective?

BACKGROUND AND OBJECTIVES

To determine whether irrigation of the sub-Tenon's space with anesthetic agents during pars plana vitrectomy (PPV) involving general anesthesia decreases postoperative pain, analgesic use, or nausea.

PATIENTS AND METHODS

A prospective, controlled trial of 46 consecutive patients requesting general anesthesia for PPV who were randomized to receive or not receive a sub-Tenon's space injection prior to surgery. A mixture of 3 mL of 2% lidocaine with hyaluronidase and 3 mL of 0.5% bupivacaine was used to induce local blockade. Pain, postoperative nausea, and analgesia use were evaluated.

RESULTS

Local blockade did not significantly alter the proportion of reported pain at 30 minutes and 2, 4, and 24 hours after the operation. The local blockade had no effect on reducing postoperative nausea or the number of patients requiring pain medication.

CONCLUSIONS

Local blockade prior to surgery in patients undergoing PPV under general anesthesia does not significantly decrease postoperative pain, analgesic use, or nausea.

Phacoemulsification with topical anesthesia performed by resident surgeons

PURPOSE

To evaluate and compare the outcomes in phacoemulsification cases performed by resident surgeons using topical anesthesia or retrobulbar anesthesia.

SETTING

Department of Ophthalmology, Emory University, Atlanta, and Department of Veterans Affairs Medical Center, Decatur, Georgia, USA.

METHODS

This was a retrospective review of phacoemulsification cases performed by resident surgeons during 1 academic year. Variables analyzed included patient age and sex, preexisting conditions limiting final acuity, and type of anesthesia used. Outcomes measured included intraoperative and postoperative complications and final visual acuity.

RESULTS

Of the 291 cases analyzed, 119 (40.9%) were retrobulbar and 172 (59.1%) were topical. Residents began using topical anesthesia after a brief introductory period with retrobulbar anesthesia. Vitreous loss occurred in 15 cases (5.1%), 8 retrobulbar (6.7%) and 7 topical (4.1%) (P =.42). Postoperative complications occurred in 30 cases (10.3%), 17 topical (9.9%) and 13 retrobulbar (10.9%) (P =.85). Overall, 245 cases (84.2%) achieved a final best corrected visual acuity (BCVA) of 20/40 or better. When cases with preexisting conditions limiting final acuity were eliminated, 92.1% achieved a final BCVA of 20/40 or better. More topical cases (112, 65.1%) than retrobulbar cases (64, 53.8%) achieved a final BCVA of 20/25 or better (P =.06), and more topical cases (149, 86.6%) than retrobulbar cases (96, 80.7%) achieved a final BCVA of 20/40 or better (P =.19).

CONCLUSION

Topical anesthesia is safe and efficacious for phacoemulsification performed by resident surgeons early in training after a brief introduction to phacoemulsification using retrobulbar anesthesia.

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.