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Show J. Clin. Neuro-ophthalmol. 2: 159-161, 1982. Complications of Retrobulbar Marcaine Injection HUMBERTO P. BELTRANENA, D.O. MARIO J. VEGA, M.D. JESUS J. GARCIA, M.D. GEORGE BLANKENSHIP, M.D. Abstract Respiratory arrest following retrobulbar marcaine injection has been described with increasing frequency. The following case reports document the occurrence and provide some insight to its management. A possible solution to the problem is suggested. In 1981, Beltranena et al.I reviewed the literature and reported three cases describing the occurrence of respiratory arrest following retrobulbar injection of marcaine for ophthalmological procedures, attributed to the inadvertent intravascular injection. They also described appropriate management for a successful outcome. Since then, a number of anecdotal reports have circulated describing what appears to be an increasing incidence. We describe three additional cases that add further insight to this problem. Case Reports Patient 1. A 51-year-old white male was admitted with a chief diagnosis of diabetic retinopathy and vitreous hemorrhage in the left eye. In the past, he had undergone pars plana vitrectomy in the right eye, with bilateral laser treatment. Significant past medical history included diabetes mellitus of 20-years duration presently treated with U-loo lente insulin (48 units in the morning), medically controlled hypertension, and occasional orthostatic hypotension. Significant laboratory findings include a fasting blood sugar of 297 m/dl with 1+ glycosuria; a BUN of 48 and electrocardiographic manifestations of left ventricular hypertrophy with strain. The From the University of Miami, School of Medicine, Bascom Palmer Eye Institute, Miami, Florida. Assistant Professor of Anesthesiology (HPB, MJV, HG); Associate Professor of Ophthalmology (GB), Bascom Palmer Eye Institute, Miami, Florida. September 1982 patient was premedicated with demerol 50 mg and vistaril50 mg intramuscularly. Intravenous 5% dextrose in water was started at a rate of 100 ml/hour. After 1 hour, 32 units of NPH insulin U-I00 were administered subcutaneously. In the holding room, retrobulbar injection with 6 ml of 0.75% marcaine was performed by the attending surgeon. Minimal proptosis of the globe was noticed. Within 2 minutes, the patient became drowsy with shallow respirations. He complained of dysphagia, became difficult to arouse and the respiratory rate decreased. The arterial blood pressure was 250/120 torr and the heart rate was 120 beats/minute. He was ventilated with 100% O 2 by face mask and anesthesia induced with 75 mg sodium thiopental. Fifty microgram of Fentanyl were given and the blood pressure decreased to 170/100. The trachea was then intubated. Anesthesia was maintained with 50% nitrous oxide and enfluorane at an inspired concentration of 1%. Respirations were initially controlled and then allowed to resume after 45 minutes. Vital signs stabilized during surgery which lasted 1 hour and 30 minutes. The patient was extubated in the operating room and transferred to the recovery room in stable condition. He was discharged to the ward within 1 hour. Patient 2. A 40-year-old white male was admitted with a chief diagnosis of diabetic retinopathy and vitreous hemorrhage in both eyes. He was scheduled for a lensectomy, pars plana vitrectomy, and scleral buckling procedure. Significant past medical history included diabetes mellitus for 8 years controlled with U-I00 NPH insulin, 20 units in the morning, and medically controlled labile hypertension. Admission laboratory findings included a fasting blood sugar of 154 mg/dl with 2+ proteinuria and 2+ acetone. The electrocardiogram was abnormal. The patient was premedicated with intramuscular demerol 50 mg and vistaril 50 mg. Intravenous 5% dextrose in water was started at a rate of 100 ml/hour and after 1 hour, 14 units of NPH insulin was administered subcutaneously. In the holding 159 Rl'lHlbulb"r M.Hc"ine Injection room, .1 retrobulb.u injection with 6 ml 0.75% m.Hc.1ine W.1S performed by the surgeon. Soon .1fter, thl' p.1tient became appreh('nsive and compl. 1ined of chills, .1 slight h.1I1d tremor was noted, .1I1d he bec.1I11l' apneic within ( minute. The Jrteriill blolld pressure W.1S 200/100 .lIld the heart rilte WilS qo. He W.1S ventil.1ted with 100% O~ by face mask, then t.1ken to the operating room; following an injection of .1Ilectine 80 mg the trachea was intub. 1ted. Anesthesia WilS maintained with 50% nitrous l,,,ide .1I1d enfluorane at an inspired concentr.Jtion of (ll/O. Respirations were initially controlled and then .1110wed to resume spontaneously within 30 minutes. Vital signs stabilized during surgery which lasted I hour and 50 minutes. He was extubated in the operating room and transferred to recovery room in stable condition. Within I hour he was 'discharged to floor care. A venous sample for marcaine levels collected after intubation yielded 0.4 mg/ml. Patient 3. An 88-year-old white female was admitted for elective cataract extraction in the left eye. Significant medical history revealed arterial hypertension and occasional angina pectoris relieved with nitroglycerin. Laboratory data revealed a hemoglobin of 10.4 g/dl and left ventricular hypertrophy by electrocardiogram. Prior to surgery, she was premedicated with intramuscular demerol 25 mg and vistaril 25 mg. She arrived to the holding room stable and alert. An intravenous infusion of 5% dextrose in water was started and a retrobulbar injection 6 cc of 0.75% marcaine and 2 cc of 2% of xylocaine was performed by the surgeon. The patient was transferred to the operating room where it was noticed that respiration ceased and the patient became cyanotic. She was ventilated with 100% O~ by face mask and the trachea was intubated. The arterial blood pressure was 260/90 and the heart rate was 140. A 100-mg of sodium thiopental was injected and blood pressure decreased to 210/100. Fifty percent of nitrous oxide and an inspired concentration 1% enfluorane were administered. Vital signs stabilized and surgery proceeded uneventfully. Surgery lasted for 50 minutes. She was extubated in the operating room and transferred to the recovery room in stable condition. The postoperative course WilS uneventful and her medical evaluJtion WilS unchanged from 'ldmission. Discussion From the time of our first report, an increilsing number of cases reporting complic.1tions following retrobulbJr m.lr(,line injections hJve circul.lted. This can be .lttributed to incre.lsed aw.ueness or wider USl' of m,Hc.1ine for retrobulb.u blocks. It should be noh'J th.lt when the respir.1tory arrest is 1'" 'J"',I\' 1I1.111.1)~,-d tlu'n- i... no pn1greo,sion to cilr-diovascular collapse, as is seen after toxic reactions to high doses of intravenous local anesthetic. It is not necessary to penetrate an artery and inject the total amount of the drug to achi.eve a temporary toxic level. If a nick is produced 10 the .utery, the presence of a large volume and high pressure in the immediate surroundings of the injection, is sufficient to allow enough free drug to enter the arterial system and flow in a retrograde manner to the cerebral circulation. Aldrete2 utilizing lidocaine in baboons showed that plasma concentrations of this drug in the internal carotid artery 6 seconds following injection were higher thilt what are generally considered to be toxic levels in primates. In the same study, the reversibility of arterial blood flow was documented not only in the head but iliso in the extremities when injections were made intrJ-arterialy at a pressure level that exceeded .lrteriJI pressure. We attempted to measure marcaine blood levels in one of our patients. However, since our immediate attention was focused in treating the patient's condition the sample was not taken until 10 minutes after the incident. In Aldrete's studies, peak cerebral blood level occurred within 30 seconds and returned to base line within 60 seconds. Therefore, the levels found in the blood after 10 minutes could not be expected to reflect what happens during the critical period. A 45-mg dose of marcaine could be more significant than previously believed if it is injected rapidly. Szeinfeld et .11. 4 reported the occurrence of total reversible blindness following attempted stellate ganglion block with only I ml of 0.25% marcaine. They attributed this to the injection of the anesthetic into the vertebral artery with subsequent vascular distribution into the central nervous system. Based on the assumption of a cerebral blood volume of 30 ml in the adult brain at any given time,' they calculated that the total concentration injected would have been 80 /lg/ml. In our cases a total concentration of 1500 /lg/mg is possible. We measured the pressure produced by a similar speed and force of air injection against a mercury manometer and found it to be in excess of 100 mm of mercury. Liquid injections of course would produce .1 higher pressure due to the lack of compressibility. In addition, using a 26-gauge needle would m.Hkedly increase this pressure because of the smaller radius. Other possible solutions that deserve investigation would be to lower the volume and/or concentration of the local anesthetic or to ch.mge the ph of the solution in order to decrease the total concentration of free drug available for entrance into the arterial circulation. In summary, we have found that by slowing the speed of injection, using a 23-gauge needle and aspirating before injection, no more incidents have been encountered. The availability of adequate emergency equipment and cardiopulmonary resus- /_'e:1FP ,! gf C!iriSd! Neuro-o~thalmology citation-trained personnel should be .1 must when retrobulbar injections are performed. References 1. Beltr.lIle Il.l , H.P., Veg.l. M.I.. Kirk N.. ,lnd HI.ml..('I1ship, G.: In.ldvertent intr.lV.1S(ul.u bupiv,K.line injection following retwbulb.H bl",'l... l~('h' ArH'sth. 1981; 6: lottl-1S I. 2. Aldrete, LA., Ronlll-S.ll.lS, F.. Anlr.l. 5., Wilson, R., .1Ild Rutherford, R.: Reverse .uteri.11 blood flow .IS ,I pathw.ly for l"l'ntr.ll IWf\',lUS system t",i,' responses September 1982 Beltranena, et al. following injection of local .lnesthetics. Anesth. An. l/g. 197t1; 57: 428-33. 3. I'enn, R.D., W.llser, R., .1I1d Ackerman, L.: Cerebral blood volume in man: Computer analysis of a computerized br.lin scan. '.A.M.A. 172: 1493, 1960. 4, Szeinft·IJ, M., Lauren(io, M., and rallares, V.S.: Tot.ll reversible blindness following attempted stell. lte g.mglion block. Anesth. An,Jig. 1981; 60: 6890<) 0. Write for reprints to: HumbE'rto r. Beltranena, D.O., B.lswm I'almer Eye Institute, P.O. Box 016880, Miami, Florilb 3310 I. 161 |
