LAST PRSENTING AS OBTUNDATION AND RESPIRATORY ARREST A 30yr old, 45kg female with no medical co-morbidities was scheduled to undergo mastectomy of left breast. The procedure was planned under combined thoracic paravertebral block with general anaesthesia. After securing an iv access and instituting standard monitoring, with the patient in sitting position the left thoracic paravertebral space was located at T5 level with a 18G Tuohy needle by loss of resistance to air technique, and a catheter was threaded and fixed at 9cm. After confirming a negative aspiration for blood and CSF, paravertebral block was initiated with 15mL of 0.5% bupivacaine injected in aliquots of 3-5mL with intermittent aspiration. Patient positioned supine after administration of the local anaesthetic was noted to be drowsy but responding to oral commands within about 1min. Within the next 1-2min patient became obtunded and had apnoea. No haemodynamic instability was noted during this period. Patient was immediately ventilated with 100% oxygen via bag and mask and another additional iv access secured. Suspecting an uncommon presentation of local anesthetic toxicity Lipid rescue therapy was immediately initiated with a bolus of 70mL Intralipid 20% followed by an infusion of 12mL/hr. Airway was secured with No.3 LMA Proseal, after administering thiopentone 100mg, fentanyl 30mcg and atracurium 20mg. As the patient was haemodynamically stable the surgery was proceeded as planned under sevoflurane anaesthesia. The patient remained haemodynamically stable throughout. At the end of the procedure which took 60min, neuromuscular blockade was reversed and patient was extubated. Patient now was conscious and oriented. Lipid infusion was stopped 10min after patient was extubated. Patient was observed in HDU for the next 24hr, and she remained stable without any untoward incidents. The next day when buprenorphine 60mcg in 5mL was administered through the catheter for postoperative analgesia patient complained of feeling excessive sleepiness and had two episodes of vomiting. This hinted to the possibility of catheter being intravascular. A contrast study to confirm vascular position of the catheter could not be undertaken due to lack of patient consent. The catheter was later removed. A test dose before initiating the primary block may have been a good practice as it would have indicated inadvertent intravascular placement of the catheter.
A 30yr old, 45kg female with no medical co-morbidities was scheduled to undergo mastectomy of left breast. The procedure was planned under combined thoracic paravertebral block with general anaesthesia. After securing an iv access and instituting standard monitoring, with the patient in sitting position the left thoracic paravertebral space was located at T5 level with a 18G Tuohy needle by loss of resistance to air technique, and a catheter was threaded and fixed at 9cm. After confirming a negative aspiration for blood and CSF, paravertebral block was initiated with 15mL of 0.5% bupivacaine injected in aliquots of 3-5mL with intermittent aspiration. Patient positioned supine after administration of the local anaesthetic was noted to be drowsy but responding to oral commands within about 1min. Within the next 1-2min patient became obtunded and had apnoea. No haemodynamic instability was noted during this period. Patient was immediately ventilated with 100% oxygen via bag and mask and another additional iv access secured. Suspecting an uncommon presentation of local anesthetic toxicity Lipid rescue therapy was immediately initiated with a bolus of 70mL Intralipid 20% followed by an infusion of 12mL/hr. Airway was secured with No.3 LMA Proseal, after administering thiopentone 100mg, fentanyl 30mcg and atracurium 20mg. As the patient was haemodynamically stable the surgery was proceeded as planned under sevoflurane anaesthesia. The patient remained haemodynamically stable throughout. At the end of the procedure which took 60min, neuromuscular blockade was reversed and patient was extubated. Patient now was conscious and oriented. Lipid infusion was stopped 10min after patient was extubated. Patient was observed in HDU for the next 24hr, and she remained stable without any untoward incidents. The next day when buprenorphine 60mcg in 5mL was administered through the catheter for postoperative analgesia patient complained of feeling excessive sleepiness and had two episodes of vomiting. This hinted to the possibility of catheter being intravascular. A contrast study to confirm vascular position of the catheter could not be undertaken due to lack of patient consent. The catheter was later removed. A test dose before initiating the primary block may have been a good practice as it would have indicated inadvertent intravascular placement of the catheter.