Visual outcomes, efficacy, and surgical complications associated with intracameral phenylephrine 1.0%/ketorolac 0.3% administered during cataract surgery

Pharmacological management of intra-operative miosis during cataract surgery

Cataract surgery requires a well-dilated and stable pupil for a good outcome. Unexpected pupillary constriction during surgery increases the risk of complication. This problem is more pronounced in children. There are now pharmacological interventions that help tackle this unforeseen happening. Our review discusses the simple and quick options available to a cataract surgeon when faced with this dilemma. As cataract surgical techniques continue to improvise and get faster, an adequate pupil size is of paramount importance. Various topical and intra-cameral drugs are used in combination to achieve mydriasis. Despite good pre-operative dilation, the pupil can be quite unpredictable during surgery. Intra-operative miosis limits the field of surgery and increases the risk of complications. For example, if the pupil size decreases from 7 mm to 6 mm, this 1 mm change in pupil diameter will lead to a decrease of 10.2 mm2 in the area of surgical field. Making a good capsulorhexis with a small pupil can be a challenge, even for an experienced surgeon. Repeated touching of the iris increases the risk of fibrinous complications. Removal of cataract and the cortical matter becomes increasingly difficult. Intra-ocular lens implantation in the bag also requires adequate dilation. When dealing with challenging cases like lens subluxation, pseudo-exfoliation, and zonular dehiscence, a small pupil further increases the risk and adversely affects the surgical outcome. Hence, achieving and maintaining adequate mydriasis throughout surgery is essential. This review highlights the risk factors for small pupils during surgery and current management strategies.

Pain control and reduction of opioid use associated with intracameral phenylephrine1.0%-ketorolac 0.3% administered during cataract surgery

PURPOSE

To compare pain and the need for the opioid fentanyl use associated with the administration of phenylephrine 1.0%-ketorolac 0.3% (P/K) with those of epinephrine administration during cataract surgery.

SETTING

Ambulatory surgery center.

DESIGN

Single-center, prospective, randomized, double-masked, self-controlled trial.

METHODS

Patients undergoing bilateral, topical anesthetic cataract surgery were randomized to receive either intracameral P/K or epinephrine in their balanced salt solution for the first eye and the other for the second eye, 2 weeks later. Fentanyl was used to manage intraoperative pain. The primary end point was the need for fentanyl administration intraoperatively. Secondary outcomes included pain measurements; surgery duration; effective phacoemulsification time; pupil size; and complications.

RESULTS

112 eyes of 56 patients were enrolled. Significantly fewer eyes in the P/K group (7 [12.5%]) than in the epinephrine group (19 [33.9%]; P = .013) required intraoperative fentanyl administration. Mean pain scores were lower in the P/K group than those in the control group at all timepoints. For patients with no pain to mild pain (pain scores ≤ 3), 85.7% (n = 48) of the P/K group and 58.9% (n = 33) of the epinephrine group met this benchmark ( P = .003) intraoperatively. The combined outcome, the number of patients not receiving intravenous fentanyl and experiencing no pain to mild pain, was significantly higher in the study (82.1%, n = 46) than in the control group (58.9%, n = 33; P = .013).

CONCLUSIONS

P/K administration significantly reduced pain and the need for fentanyl use. Using P/K is a practical way for cataract surgeons to provide better patient care and reduce the need for intraoperative opioids.

The safety of intracameral phenylephrine - A systematic review

Intracameral phenylephrine is commonly used in ophthalmic surgery as an alternative or supplement to mydriatic eye drops; hence, the importance of an evidence-based understanding of its risk-benefit profile is vital. We performed a comprehensive search in the PubMed, Google Scholar and Cochrane databases for published studies and case reports relating to the use of intracameral phenylephrine. Articles from 1958 to 2021 with the following keywords were used: "intracameral phenylephrine", "intracameral mydriatics", "phenylephrine", "pupil dilation", "complications". Intracameral phenylephrine was first used in 2003 as an alternative to topical mydriatics. Since then, it is being increasingly used with a variety of benefits, including rapid onset of mydriasis, and cost-effectiveness. There are various case reports, however, of ocular and systemic complications associated with intracameral phenylephrine such as generation of free radicals, toxic anterior segment syndrome, inconsistent pupillary dilation during surgery, and ventricular fibrillation. Alternatives to intracameral phenylephrine such as iris hooks, a Malyugin ring, intracameral epinephrine, and intracameral tropicamide were compared with intracameral phenylephrine. Intracameral phenylephrine appears to have a good safety profile.

Safety and efficacy data supporting U.S. FDA approval of intracameral phenylephrine and ketorolac 1.0%/0.3% for pediatric cataract surgery: clinical safety and pupil and pain management

PURPOSE

To assess the safety of phenylephrine and ketorolac (PE/K) 1.0%/0.3% compared with phenylephrine (PE) 1.0% in children aged 0 to 3 years undergoing cataract surgery. The effect of PE/K to PE on intraoperative pupil diameter and postoperative pain were also compared.

SETTING

Multicenter study in the United States.

DESIGN

Randomized double-masked phase 3 clinical trial.

METHODS

This study was powered to assess safety only. Depending on randomization, 4 mL of PE/K 1.0%/0.3% or PE 1.0% was injected into the surgical irrigation solution. Safety endpoints were assessed up to 90 days postoperatively. From surgical videos, a masked central reader measured the change in pupil diameter from immediately prior to incision to wound closure. Postoperative pain was measured using Alder Hey Triage Pain Score at 3 hours, 6 hours, 9 hours, and 24 hours following wound closure and recorded by parent/caregiver.

RESULTS

Seventy-two patients received masked intervention. There were no notable changes in vital signs or ophthalmological complications in either group. Mean change in pupil diameter was similar between PE/K 1.0%/0.3% and PE 1.0% (mean difference in area under the curve -0.071; P = .599). Postoperative ocular pain scores and overall mean scores were lower in PE/K group at all individual time points, and differences in overall mean scores were statistically significant at 6 and 24 hours (P = .029 and 0.021, respectively).

CONCLUSIONS

PE/K 1.0%/0.3% was safe for use in children and maintained mydriasis during cataract surgery. Postoperative pain levels were lower in the PE/K 1.0%/0.3% group.

Intraoperative floppy iris syndrome: an updated review of literature

Intraoperative Floppy iris syndrome(IFIS) remains a challenge for surgeons during phacoemulsification. Initially, it was related to the use of tamsulosin, an alpha adrenergic receptor blocker used in benign prostatic hyperplasia. Subsequently, other alpha adrenergic receptor such as alfuzosin, terazosin and doxazosin alongwith different other class of medications and systemic risk factors were identified. Other class of medications includes 5-alpha reductase inhibitor, angiotensin receptor antagonist, benzodiazepines, antipsychotics and antidepressants. Other risk factors include increasing age, male gender, diabetes, hypertension and decreased preoperative pupil diameter. It is very important for surgeons to identify these risk factors preoperatively and take appropriate preoperative and intraoperative measures to tackle the dreaded complications of IFIS. Sometimes, it is important for an ophthalmologist to work in cooperation with physician and urologist to minimize the complications. In conclusion, awareness of the risk factors associated with IFIS, their detailed preoperative assessment and intraoperative measures and surgical intervention is crucial in addressing IFIS. Lack of awareness can turn a routine, uneventful surgery into one with significant visual morbidity.

Efficacy of Nepafenac versus Flurbiprofen in Maintaining Intraoperative Mydriasis During Phacoemulsification: A Comparative Study

Purpose

To compare the efficacy of topical nepafenac (0.1%) with flurbiprofen (0.03%) in maintaining intra-operative mydriasis during phacoemulsification surgery.

Patients and Methods

This study comprised of 160 patients, who were divided into two arms of 80 each (arms A and B) after randomisation. Pre-operatively, all patients received one drop of tropicamide 0.8% and phenylephrine 5% (combination), 4 times, at an interval of 15 minutes on the day of surgery. Thereafter, Nepafenac drop in arm A/Flurbiprofen drop in arm B was administered 4 times, at an interval of 15 minutes keeping a gap of 10 minutes between tropicamide-phenylephrine and any of the experimental drugs. Phacoemulsification was performed one hour after the administration of last drop. Both vertical and horizontal pupillary diameter were measured at three steps; immediately before the surgical incision (baseline), at the end of emulsification of nucleus (before irrigation and aspiration) and at the end of surgery (after stromal hydration).

Results

The difference in pupillary diameter between two groups, was statistically insignificant for vertical diameter (P = 0.08) and horizontal diameter (P = 0.28) at the start of surgery. On the other hand, pupillary diameter difference was statistically significant after emulsification of nucleus and at the end of surgery as well when both vertical (P < 0.05) and horizontal diameter (P < 0.05) were considered. The total reduction in pupillary diameter (both vertically and horizontally) was significantly less in the Nepafenac as compared to Flurbiprofen group (P < 0.05). Analysis of mean cumulative dissipated energy did not document any appreciable difference between the two groups. Phacoemulsification time analysis yielded statistically significant results (P = 0.004) between the Nepafenac and Flurbiprofen group.

Conclusion

In the present study, topical Nepafenac (0.1%) proved to be more efficacious in maintaining intra-operative mydriasis during phacoemulsification surgery as compared to topical Flurbiprofen (0.03%).

Effect Of Intracameral Phenylephrine And Ketorolac 1.0%/0.3% On Intraoperative Pain And Opioid Use During Cataract Surgery

Purpose

To compare the effect of Omidria (phenylephrine and ketorolac 1.0%/0.3%) vs epinephrine on pain reduction and opioid usage during cataract surgery.

Patients and methods

Sixty patients at a single center underwent femtosecond laser (FLACS) or conventional phacoemulsification under topical lidocaine gel anesthesia and intracameral preservative-free lidocaine 1%. Eligible participants were prospectively assigned to receive either intracameral phenylephrine and ketorolac 1.0%/0.3% or intracameral epinephrine. All patients received standardized pre- and post-operative topical therapy. Intravenous (IV) fentanyl was administered for ocular discomfort in patients who complained of intraoperative pain. Outcome measures included both pain (measured by mean visual analog scale (VAS) pain scores from 0 (no pain) to 10 (extreme pain)) and the use of IV fentanyl during surgery. A composite endpoint identified “responders” as being patients who: (1) did not require fentanyl and (2) experienced no to minimal pain (VAS score ≤ 3).

Results

Forty-one patients were in the phenylephrine and ketorolac 1.0%/0.3% (study) group and 19 were in the epinephrine (control) group. Mean VAS pain scores were significantly (48.9%) lower in the study group than the control group (2.3 vs 4.5; P < 0.0001). The proportion of patients with VAS scores ≤ 3 was significantly greater in the study group (85.0%) than the control group (31.6%) (P < 0.0001). A smaller proportion of patients required intraoperative fentanyl in the study group compared to the control group (9.8% vs 42.1%; P = 0.006). For the composite endpoint, patients receiving phenylephrine and ketorolac 1.0%/0.3% were 94% less likely to require fentanyl or to have moderate-to-severe pain (pain VAS ≥ 4; OR, 0.06; 95% CI 0.02–0.24) than patients receiving epinephrine.

Conclusion

Our results suggest that the routine use of intracameral phenylephrine and ketorolac 1.0%/0.3% during cataract surgery can significantly reduce patient pain as well as the need for opioids.