Comparison of changes in blood pressure in phacoemulsification cataract surgery performed via topical and peribulbar anaesthesia: A cohort study

Background

The purpose of study was to compare the changes in blood pressure in patients undergoing phacoemulsification cataract surgery under topical and peribulbar anaesthesia during preoperative, intraoperative and postoperative period.

Methods

In this prospective cohort study, 240 patients undergoing phacoemulsification were divided into topical (Group 1) and peribulbar (Group 2) equally. Proparacaine 0.5% drops were used for topical anaesthesia, and Inj lignocaine with Inj bupivacaine were used to give peribulbar anaesthesia. Preoperative blood pressure was taken 30 min before surgery with automated sphygmomanometer. Intraoperative blood pressure was taken during phacoemulsification, and postoperative blood pressure was taken 1 h after surgery. Outcomes assessed were systolic, diastolic and mean blood pressure.

Results

Systolic blood pressure in Group 1 was significantly increased in the intraoperative phase, whereas it was significantly decreased in Group 2 in the intraoperative phase. Diastolic and mean blood pressure in Group 1 showed no significant change, whereas in Group 2, both showed significant reduction in intraoperative and postoperative phases.

Conclusion

The increase in intraoperative systolic blood pressure in topical group could be due to discomfort from microscope light, iris manipulation, irrigation and aspiration during surgery. The decrease in intraoperative systolic and diastolic blood pressure in peribulbar group could be due to systemic absorption of local anaesthetic. The mean preoperative systolic blood pressure was also higher in the topical group, which could be due to anxiety or stress under topical anaesthesia. The changes in blood pressure need to be observed so that timely intervention can be made to achieve favourable postoperative outcome.

Computed tomography scan measurements of the globe and orbit to assess the risks of traumatic complications from medial peribulbar anaesthesia

Complications of peribulbar anaesthesia include retrobulbar haemorrhage, globe perforation and brainstem anaesthesia. Therefore, this study took measurements relating the proximity of medial canthus to the optic nerve and also the safe angle between orbit and globe using 200 multiplanar reconstructed computed tomography (CT) images of the orbit. The principal results show that in 1.5% of the sample, the optic nerve is within 20 mm of the medial canthus, with a minimum distance of 15 mm. One% have a safe angle of 10 degrees or less between bone and globe. None of the demographic data, nor axial length were predictive of these results. We have shown that there are a minority of patients with unusual orbital anatomy. This places them at a theoretical higher risk of complications. These cases are not currently predicted by measured data.

Comparison of peribulbar block and general anaesthesia in mechanical vitrectomy: a prospective observational study

INTRODUCTION

Vitrectomy surgery is a common procedure for the treatment of several types of ophthalmologic conditions. It can be performed under regional anaesthesia with peribulbar block (PB) or general anaesthesia (GA). There are no evidence-based recommendations on the optimal anaesthesia strategy for this procedure. The aim of this study was to compare the advantages of PB and GA for vitrectomy surgery.

MATERIALS AND METHODS

A prospective observational study was conducted on adults submitted for mechanical vitrectomy between January 2017 and December 2017. Demographic and perioperative data were collected, namely ASA physical status, median arterial pressure, heart rate, postoperative opioid consumption, postoperative nausea and vomiting, times of induction, surgery, recovery, and hospital stay and costs considering medication and material needed. Statistical analysis was performed using SPSS v.25, with chi-square, Fisher and Mann-Whitney U tests, according to the type of variables analysed.

RESULTS AND DISCUSSION

We included 179 patients submitted for mechanical vitrectomy: 91 (51%) with PB and 88 (49%) under GA. Patients submitted to PB were older (69.0 vs. 64.5 years, p=.006) and presented with higher ASA physical status (p=.001). For haemodynamic outcomes, patients submitted to PB presented with less variation of median arterial pressure (-3.0 vs. -13.5mmHg, p=.000) and with no significant differences in heart rate (-2.0 vs. -3.0 bpm, p=.825). In the postoperative period, the PB group presented with decreased need of postoperative analgesia (0.0 vs. 5.0, p=.026) and a lower incidence of nausea and vomiting (1.0 vs. 12.0, p=.001). Times related to anaesthesia and surgery were better in PB group, with shorter induction time (10.0 vs. 11.0min, p=.000), surgery time (56.5 vs. 62.0min, p=.001), recovery time (10.0 vs. 75.5min, p=.000), and hospital stay (2.0 vs. 3.0 days, p=.000). When analysing costs, PB was less expensive than GA (4.65 vs. 12.09 euros, p=.021) CONCLUSION: PB is a reliable and safe alternative to GA for patients undergoing mechanical vitrectomy, permitting good anaesthesia and akinesia conditions during surgery, better haemodynamic stability, and less postoperative complications, especially in older patients and those with more comorbidities.

Orbital supratrochlear fistula secondary to anaesthetic block in cataract surgery

A case is described of a woman with history of right peribulbar nerve block prior to cataract surgery that, within a few days, presented with a trochlear intraorbital arteriovenous fistula. This was resolved without sequelae after three months by performing intermittent homolateral carotid massages. This is the first case of supratrochlear intraorbital arteriovenous fistula. There are only 8 cases reported of traumatic intraorbital arteriovenous fistula, and only one was with post-peribulbar anaesthesia.

Does the addition of hyaluronidase improve the quality of peribulbar anesthesia in cataract surgery? - A randomized double blinded study

Purpose

To determine the necessity of hyaluronidase as an anesthetic adjuvant for peribulbar anesthesia during cataract surgery and to assess differences in anesthetic outcomes in the absence of hyaluronidase.

Methods

In this double blinded randomized study, 202 patients reporting for surgery for senile cataract in their first eye under regional ocular anesthesia without pre-existing extra ocular movement restriction were randomly divided into 2 groups: Group 1 – anesthesia without hyaluronidase, Group 2 – anesthesia with 50 IU/ml Hyaluronidase. Peribulbar block with 5 ml of anesthetic mixture of 2% lignocaine with 1:200000 adrenaline and 0.5% bupivacaine with or without hyaluronidase was performed with 3 ml deposited in the infero-medial quadrant and 2 ml in the supero-medial quadrant followed by ocular massage. Surgeons’ score for akinesia, patients’ score for analgesia, augmentation of block if any and extra ocular movements on first post-operative day were compared between the groups.

Results

There was no statistically significant difference between the two groups in akinesia (p = 0.22, 0.68 and 0.98), analgesia (p = 0.44 and 0.09) or requirement of anesthetic augmentation (p = 0.3). Extraocular movement restriction was not noted in any patient. Onset of akinesia and analgesia was earlier in Group 2 (p = 0.004 and p = 0.005 respectively).

Conclusions

Hyaluronidase is not an essential adjuvant for peribulbar block for cataract surgeries. Appropriate deposition of a smaller volume of anesthetic agent and adequate ocular massage provide adequate and safe 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.