Venous levels of lignocaine and bupivacaine after peribulbar block

Abstract

SummaryTwentyfive patients undergoing elective cataract day surgery were studied after receiuing a dual-injection peribulbar block with a mixture consisting of equal volumes of 2% lignocaine and 0.75% bupivacaine with hyaluronidase. A maximum of' 10 mi of solution was used for the initial hlock; supplementary injections of up to lOml were given lo five patients. Venous blood was taken prior to the block and then 1, 10, 20, 30, 60 and 90min after the block. The peak mean concentrations of lignocaine (0.722 p g . m l~ ' ) and bupivacaine (0.353 pg.ml-' ) were found at I s 2 0 min after injection when no top-up was given and at 10 min after the top-up injection when required. AN measured serum concentrations of lignocaine and bupivacaine were below the accepted toxic levels of the two drugs. However, the highest individual toxicity score after a top-up was 0.915 which was very close to the toxicity threshold (= I) when a scoring system was used to assess the combined levels.

Clinical efficacy and pharmacokinetics of 1% ropivacaine and 0.75% bupivacaine in peribulbar anaesthesia for cataract surgery

“…The maximum tolerated total venous plasma concentrations of ropivacaine and bupivacaine have been reported to be 2.2 vs. 2.0 mg.ml ¹1 respectively, following intravenous administration in healthy volunteers [4]. In our study, the maximum concentrations of bupivacaine were well below this value and in agreement with those published earlier [19,20]. At 120 min, the mean concentrations of both ropivacaine and bupivacaine were below reported toxic values.…”

Comparison of 0.75% levobupivacaine with 0.75% racemic bupivacaine for peribulbar anaesthesia

“…A wide interindividual variation in plasma concentrations has been demonstrated after peribulbar anaesthesia with bupivacaine and lignocaine. Barr et al recorded near toxic levels in two of 12 subjects receiving the mixture without adrenaline, and Gao and Budd noted a similar level in one of 25 patients, although none of these patients experienced toxic symptoms or signs [12,13].…”

“…Transient ECG changes in other patients may have been missed as we performed the second ECG examination after surgery, approximately 1 h after the first injection. ECG changes may be more likely to occur 10-20 min after the injection when plasma levels have peaked [13]. In addition we monitored ECG lead II only during anaesthesia and surgery so may have missed ECG alterations.…”

Efeitos cardiovasculares da mepivacaína com epinefrina seguida de hialuronidase: ensaio duplo-cego controlado em cirurgias bilaterais de terceiros molares inferiores

“…O lado em que foi realizada a primeira cirurgia foi escolhido de modo aleatório, como também a solução que seria utilizada primeiro (hialuronidase ou placebo). Na cirurgia realizada do outro lado, era necessária a utilização da outra No protocolo utilizado em oftalmologia, quando a hialuronidase foi injetada junto ao AL, não foram observadas alterações cardiovasculares significativas (BARR et al,1995;GAO;BUDD, 1996;NATHAN et al, 1996;SOARES et al, 2002). Ainda, Nathan et al (1996) …”

“…Em cirurgias oftalmológicas, vários estudos vêm sendo realizados com o objetivo de melhorar a eficácia dos bloqueios anestésicos tanto retrobulbar (KALLIO; PALOHEIMO; MAUNUKSELA, 2000; SARVELA; NIKKI, 1992) como peribulbar (BARR et al, 1995;GAO;BUDD, 1996;HAMADA et al, 2005;KALLIO;PALOHEIMO;MAUNUKSELA, 2000;NICOLL et al, 1986;SOARES et al, 2002).…”