Search

Effective pain control after major surgery in neonates presents many challenges. Parenteral opioids (and co-analgesics) are often used but inadequate analgesia and oversedation are not uncommon. Although continuous thoracic epidural analgesia is highly effective and opioid-sparing, its associated risks and the need for staff with specialised skills and/or neonatal intensive care unit staff buy-in may preclude this option even in many academic centres. We present the case of a six-day-old infant who underwent upper abdominal surgery and received intermittent morphine doses via a tunnelled caudal epidural catheter, which provided satisfactory analgesia and facilitated early extubation.

We conducted a small pilot observational study of the effects of bilateral thoracic paravertebral block (BTPB) as an adjunct to perioperative analgesia in coronary artery bypass surgery patients. The initial ropivacaine dose prior to induction of general anaesthesia was 3 mg/kg, which was followed at the end of the surgery by infusion of ropivacaine 0.25% 0.1 ml/kg/hour on each side (e.g. total 35 mg/hour for a 70 kg person). The BTPB did not eliminate the need for supplemental opioids after CABG in the eight patients studied. Moreover, in spite of boluses that were within the manufacturer's recommendation for epidural and major nerve blocks, and an infusion rate that was only slightly higher than what appeared to be safe for epidural infusion, potentially toxic total plasma ropivacaine concentrations were common. We also could not exclude the possibility that the high ropivacaine concentrations were contributing to postoperative mental state changes in the postoperative period. Also, one patient developed local anaesthetic toxicity after the bilateral paravertebral dose. As a result, the study was terminated early after four days. The question of whether paravertebral block confers benefits in cardiac surgery remains unanswered. However, we believe that the bolus dosage and the injection rate we used for BTPB were both too high, and caution other clinicians against the use of these doses. Future studies on the use of BTPB in cardiac surgery patients should include reduced ropivacaine doses injected over longer periods.

If tracheal intubation is not possible using direct laryngoscopy, one option is to use a laryngeal mask airway (LMA) through which an endotracheal tube (ETT) can be passed. In children, however, the size of an uncuffed ETT that can pass through the lumen of an LMA is sometimes too small for the trachea, resulting in gas leakage around the ETT. Using a cuffed ETT may reduce the gas leak but withdrawal of the LMA is then prevented by the pilot balloon. In this study, the largest sizes of cuffed and uncuffed Mallinckrodt™ ETTs that could pass with ease through various sizes of paediatric Classic™ and ProSeal™ LMAs were documented. For cuffed ETTs, withdrawal of the LMA was made possible by simply cutting off the pilot balloon. The ETT cuff-inflating mechanism was then repaired by passing a 20 or 22 gauge cannula into the cut end of the inflating tubing. The proximal end of the cannula was then connected to a one-way valve or a three-way stopcock. This technique of cutting off the pilot balloon of the cuffed ETT made it possible to use paediatric cuffed ETTs in exchange for the LMAs tested. The task was easy to perform. Subsequent repair of the cuff-inflation tubing was effective and could withstand high pressures. These findings indicate that it is possible to pass cuffed ETTs through paediatric LMA lumens, which can provide ventilation without gas leaks, unlike uncuffed ETTs.

We describe a novel technique, previously applied to small children, for adult one-lung anaesthesia in which a single-lumen endotracheal tube is used with an endobronchial balloon blocker. The main aims of the technique are to reduce the likelihood of cephalad displacement of the balloon into the trachea and to facilitate directional placement of the endobronchial balloon. We present five illustrative cases of one-lung anaesthesia in patients of adult size, in which the endotracheal tube-endobronchial balloon technique was considered preferable to the use of a double-lumen tube technique. The situations included difficult intubation, need for postoperative ventilation, a tortuous trachea and an unexpected need to perform one-lung anaesthesia. The technique involved deliberate placement of the endotracheal tube tip near the carina to block cephalad dislodgement of the blocker. The chance of the balloon blocking the endotracheal tube tip could be further reduced by having the intraluminal endobronchial balloon blocker emerge through the Murphy eye.

Recombinant activated factor VII (rFVIIa) is a powerful prohaemostatic agent that theoretically predisposes to thrombosis after peripheral vascular surgery. We report the use of rFVIIa to reduce bleeding in a patient after axillofemoral bypass grafting for ruptured aorto-iliac pseudoaneurysm. Despite the increased risk of thrombosis, the patient made an uneventful recovery with preserved graft patency. The favourable result suggests that rFVIIa should be considered even in vascular surgical patients, if the risks of continued bleeding outweigh those of thrombosis. Better risk estimation is only possible if reports of rFVIIa use in vascular patients continue to appear and through controlled trials.

This prospective before-and-after observational study investigated the effect of upper airway anaesthesia on dynamic airflow. Six consenting ASA 1 adults, all authors of this study, underwent a series of Spirometric measurements before and after topical anaesthesia of the upper airway using lignocaine. Peak inspiratory flow rate, forced inspiratory flow between 25% and 75% of the maximum inhaled volume, forced expiratory volume at 1 second, and forced vital capacity in the supine and sitting positions were measured. The measured inspiratory parameters were significantly reduced after lignocaine topical anaesthesia of the upper airway. Expiratory flow parameters were not affected. We conclude that topical anaesthesia of the upper airway leads to dynamic inspiratory airflow limitation.

Surgical emphysema is a well-recognised complication of laparoscopic surgery, but its impact on end-tidal carbon dioxide levels and carbon dioxide elimination is seldom reported and may not be fully appreciated by anaesthetists. Four cases are presented where extensive surgical emphysema occurred during laparoscopic surgery. The visual display of the anaesthetic record using the software program Monitor showed substantial rises in end-tidal carbon dioxide levels and allowed calculation of the carbon dioxide elimination, which increased two- to three-fold above normal levels. Having a visual record of carbon dioxide changes facilitated the recognition of surgical emphysema in three out of the four cases. Strategies such as estimating and tracking changes in carbon dioxide elimination from the minute ventilation and end-tidal carbon dioxide levels may assist in early identification, and palpating for surgical emphysema is recommended during laparoscopy if other causes of increased carbon dioxide levels are excluded.

Perioperative hypoxaemia is a common but serious problem with well recognised causes. However, an anomalous bronchus causing lobar collapse as a cause is seldom mentioned. A healthy young male patient was anaesthetised for a knee operation. He required reintubation immediately postoperatively for hypoxia. He was found to have right upper lobe collapse. Fibreoptic examination of the trachea demonstrated an anomalous bronchus as the cause. Intra-operatively, the endotracheal tube had been inserted too deeply and the bronchial orifice had been obstructed by the tip. It took several hours for the lung to re-expand. Greater awareness of this potential complication is needed.

Prompted by an actual case of potentially life-threatening infusion pump malfunction, we investigated the effects of wire breakage(s) within the syringe size sensor circuit in a Graseby 3400 infusion pump.The circuit wires within the sensor were systematically broken.The syringe sizes recognised by the sabotaged circuit and the actual sizes of syringes inserted into the pump were compared.Thirty-eight per cent of the possible wire breakages resulted in a smaller syringe size being recognized, causing the infusion rate to be too fast, and 38% of the possible wire breakage resulted in a larger syringe size being recognized, causing the infusion rate to be too slow.The volume delivered for each different size of Terumo syringe as a function of distance travelled by the plunger was measured.The errors ranged from 0.4 to 2.6 times that of the expected rate.Only 1.3% of the possible wire breakage(s) were recognised as errors by the pump.The infusion rates were not affected in 22.5% of the cases.Wire breakage within the syringe size sensor in infusion pumps is yet another potential source of infusion error, with important safety implications.