Anaesthesia for massive retrosternal thyroidectomy in a tertiary referral centre

BACKGROUND

Retrosternal goitre (RSG) is an uncommon problem encountered rarely by anaesthetists working outside specialized head and neck (H&N) surgical units. Traditional anaesthetic teaching warns of difficult airway management in these patients. The incidence and extent of these problems is unclear.

METHODS

We have performed a retrospective review of the anaesthetic management all patients with massive RSG (extending to the aortic arch or beyond) presenting for thyroidectomy at University Hospital Aintree from January 2007 to May 2012.

RESULTS

Five hundred and seventy-three patients underwent a thyroidectomy procedure at Aintree University Hospitals NHS Foundation Trust (AUH) between January 2007 and May 2012. Of these, 34 cases were documented as having a RSG. Review of each patient's preoperative computerized tomography imaging identified 19 patients with massive RSG. There was one case of failed intubation. All other patients underwent uneventful tracheal intubation via direct laryngoscopy. All glands were removed through the neck with no requirement to proceed to sternotomy. There were no instances of postoperative respiratory problems or tracheomalacia. Three patients suffered recurrent laryngeal nerve (RLN) injuries.

CONCLUSION

When managed within a dedicated H&N operating theatre we have found a low incidence of difficult tracheal intubation, difficult mechanical ventilation nor postoperative respiratory difficulties in patients with massive RSG and mid-tracheal compression because of benign multi-nodular goitre. Surgical complications, however, are more frequent than those associated with cervical thyroidectomy with RLN injury and postoperative bleeding more likely.

Percutaneous tracheostomy: a 6 yr prospective evaluation of the single tapered dilator technique

BACKGROUND

The single tapered dilator (STD) percutaneous dilatational tracheostomy (PDT) technique now appears to be the single most common method of performing a tracheostomy in the critical care unit (CCU).

METHODS

A single-centre, prospective evaluation of all PDTs performed in an adult mixed surgical and medical CCU between November 2003 and October 2009 was done. All procedures were undertaken by critical care physicians. A proforma recorded intraoperative complications and technical difficulties encountered during the procedure; all patients were followed up for a minimum of 3 months for delayed complications.

RESULTS

A tracheostomy was performed on 589 patients during the study period. PDT was attempted in 576 patients and successfully completed in 572. PDT was abandoned in four patients due to bleeding, with three of these subsequently undergoing surgical tracheostomy (ST). ST was performed in 17 patients. Intraoperative technical difficulties were encountered in 149 (26%) cases. Sixteen (3%) procedures were deemed as having early complications. A further four (0.7%) cases had significant late complications including two tracheo-innominate fistulae (TIF). Both TIF patients died as a result of their complications giving a mortality directly attributable to PDT of 0.35%. There were no differences with respect to the occurrence of complications according to grade of operator.

CONCLUSIONS

PDT performed by the STD technique is a relatively safe procedure with more than 96% of procedures performed without any early or late complications. Using this technique, more than 97% of tracheostomies undertaken during the study period were performed percutaneously. Further audit at a national level is warranted to fully evaluate long-term complications after PDT.

Outcome of late-onset hospital-acquired pneumonia related to causative organism

Pneumonia caused by Pseudomonas spp. has been associated with an increase in mortality in critical care patients. Previous assessments, however, have failed to compare outcome solely with other pathogens associated with hospital-acquired pneumonia (HAP). We have performed a retrospective review of all critical care patients with late-onset HAP (hospital inpatient stay >72 h at time of diagnosis) due to pure respiratory cultures of Pseudomonas spp., meticillin-resistant Staphylococcus aureus (MRSA) or non-pseudomonal Gram-negative (NPGN) organisms from 1998 to 2007. Casenote review involved assessments of illness severity, clinical pulmonary infection scoring (CPIS), critical care and hospital survival, and critical care length of stay. Out of 252 casenotes, 204 were reviewed. There were 186 treated cases of pneumonia. Ten patients had both pseudomonal and NPGN pneumonias during the same admission and two patients presented with community-acquired infections due to these organisms. These 12 patients were excluded from further analysis. Of the remaining 174 patients, 80 were infected with pseudomonas, 40 with MRSA and 54 had NPGN organisms. The three groups of patients were well-matched, with similar age, sex, CPIS scores, incidence of bacteraemia and Acute Physiology and Chronic Health Evaluation II scores at diagnosis. There were no outcome differences between the groups with respect to hospital and critical care survival and critical care length of stay. In this series, there appears to be no survival disadvantage associated with pseudomonal pneumonia when compared with other hospital-acquired organisms associated with HAP, where disease severity between the groups is similar.

Role of routine chest radiography after percutaneous dilatational tracheostomy

BACKGROUND

The role of routine chest radiography (CXR) after percutaneous dilatational tracheostomy (PDT) has been questioned.

METHODS

We performed a prospective observational study, on a mixed medical/surgical critical care unit in a university teaching hospital. We studied all patients undergoing PDT as part of their critical care management from November 1, 2003 until July 31, 2007. All PDTs were performed under bronchoscopic guidance. After PDT, we reviewed the immediate post-procedural films to assess the utility of routine postoperative CXR. For the purposes of CXR review, we considered a procedure to be either uncomplicated or technically difficult. Clinically relevant CXR findings were new barotrauma (pneumothorax, pneumomediastinum) or a significant change in consolidation from the pre-procedure film.

RESULTS

A total of 384 patients underwent PDT during the study period. Of these, 345 had immediate post-procedural CXRs available for review. There were 252 PDTs (73%) documented as uncomplicated. There were 93 (27%) technically difficult procedures, with 107 adverse events recorded. In 82 (24%) procedures, these difficulties were described as minor procedural complications [multiple attempts at needle insertion (> or = 3), minor bleeding or tracheal ring fracture]. Significant complications (mal-placement in the anterior mediastinum and major bleeding) were documented in 12 (3.5%) patients. New abnormalities were noted on 8 (2.3%) immediate post-procedural CXRs. In only one patient was there a new CXR change in an uncomplicated PDT.

CONCLUSIONS

Immediate CXR after uncomplicated PDT performed under bronchoscopic guidance rarely reveals unexpected radiological abnormalities. The role of CXR after PDT appears to be restricted to those patients undergoing technically difficult and complicated procedures. A change in practice to this effect will lead to reductions in both medical costs and exposure of staff and patients to ionizing radiation.

The influence of allogenic blood transfusion in patients having free-flap primary surgery for oral and oropharyngeal squamous cell carcinoma

The influence of perioperative blood transfusion in oral and oropharyngeal squamous cell carcinoma remains uncertain. It is believed that blood transfusion downregulates the immune system and may have an influence on cancer recurrence and survival. In all, 559 consecutive patients undergoing primary surgery for oral and oropharyngeal squamous cell carcinoma between 1992 and 2002 were included in this study. Known prognostic variables along with transfusion details were obtained from head and neck cancer and blood transfusion service databases, respectively. Adjusting for relevant prognostic factors in Cox regression, the hazard ratio for patients having 3 or more transfused units relative to those not transfused was 1.52 (95% confidence interval (CI) 0.93–2.47) for disease-specific and 1.52 (95% CI 1.05–2.22) for overall mortality. Blood transfusion of 3 or more units might confer a worse prognosis in patients undergoing primary surgery for oral and oropharyngeal squamous cell carcinoma. Therefore, every effort should be made to limit the amount of blood transfused to the minimum requirement.

Effect of renal failure and cirrhosis on the pharmacokinetics and neuromuscular effects of rapacuronium administered by bolus followed by infusion

BACKGROUND

Recent trials indicate that rapacuronium's pharmacokinetic characteristics are influenced by both renal failure and cirrhosis but the time course of a single bolus dose of 1.5 mg/kg is affected minimally. The authors reassessed these pharmacokinetic findings and examined the time course of the same bolus dose followed by a 30-min infusion.

METHODS

During nitrous oxide-isoflurane anesthesia, patients with normal renal and hepatic function (n = 25), those with renal failure (n = 28), and those with cirrhosis (n = 6) received a bolus dose of rapacuronium (1.5 mg/kg) followed by a 30-min infusion adjusted to maintain 90-95% twitch depression. At 25% recovery, neostigmine was administered. Blood was sampled until 8 h after the infusion to determine concentrations of rapacuronium and its active metabolite ORG9488. Rapacuronium's pharmacokinetic parameters were determined using mixed-effects modeling.

RESULTS

Onset and facilitated recovery of twitch depression were similar in the three groups. Patients with renal failure required 22% less rapacuronium to maintain target twitch depression during the infusion. Rapacuronium's plasma clearance was 24% smaller in renal failure and decreased 0.5%/yr of age; rapid distribution clearance was 51% smaller in men than in women. After the infusion, ORG9488 concentrations decreased markedly more slowly in patients with renal failure. Cirrhosis did not alter the pharmacokinetics of rapacuronium.

CONCLUSION

Rapacuronium's plasma clearance and infusion requirement were decreased by renal failure. By dosing to maintain target twitch depression, recovery was not prolonged. Cirrhosis does not affect the pharmacokinetics or neuromuscular effects of rapacuronium. Persistence of ORG9488 in patients with renal failure might prolong recovery after rapacuronium if target twitch depression is not maintained or with administration of rapacuronium for more than 30 min.

Pyroglutamic acidemia: a cause of high anion gap metabolic acidosis

OBJECTIVE

To report four cases of pyroglutamic acidemia in adults causing clinically significant acidosis.

DATA SOURCES

Patients admitted to the intensive care units of the Alfred Hospital (a quaternary referral center) and Geelong Hospital (a major regional center) with an unexplained high anion gap acidosis.

CONCLUSIONS

Pyroglutamic acidemia (5-oxoprolinemia) is a rare cause of high anion gap metabolic acidosis that should be suspected in patients presenting with sepsis, hepatic, and/or renal dysfunction who are receiving drugs such as acetaminophen, flucloxacillin, and vigabatrin after the more common causes of a high anion gap acidosis have been excluded. Should pyroglutamic aciduria be present, known precipitants should be ceased, infection should be managed aggressively, and supportive management should be instituted.

Hyaluronidase and peribulbar block

We have assessed the effect of two concentrations of hyaluronidase on the quality of peribulbar block, using a low volume, single injection technique. We studied 200 patients undergoing elective intraocular surgery, allocated randomly to one of three groups. Group 1 (n = 50) received peribulbar block with 5 ml of a 1:1 mixture of 0.5% plain bupivacaine and 2% plain lignocaine. Group 2 (n = 75) received this solution supplemented with hyaluronidase 50 iu ml-1. Group 3 (n = 75) received the same solution supplemented with hyaluronidase 300 iu ml-1. Lack of ocular motility was considered to be the only objective sign of successful block and movement of each rectus muscle was scored at 1-, 5- and 10-min intervals. If the block was successful at 5 min, the 10-min score was omitted. If the block was unsuccessful at 5 min, a second injection of 2% lignocaine 3 ml was given and additional assessments performed at 5-min intervals. At 1 min, ocular motility scores were significantly lower in group 3 compared with the control group (P < 0.05). The incidence of satisfactory block at 5 min was increased in both groups given hyaluronidase (group 2, P < 0.05; group 3, P < 0.001). There were no significant differences between groups 2 and 3 with respect to quality of block at 5 min. Hyaluronidase in both concentrations improved the quality of peribulbar block at 5 min, and when used in a concentration of 300 iu ml-1, also improved the speed of onset of block.

Attitudes of consultant anaesthetists to the Calman proposals: a questionnaire survey

We undertook a postal survey to determine the views of all consultant anaesthetists within the North West (Mersey) Regional Health Authority on the Calman proposals for a consultant-based service; replies were received from 110 (84%). Fifty (45%) indicated that they would not resume emergency residential duties, 32 (29%) indicated that they would withdraw from the emergency duty rota, 12 (11%) said they would withdraw/retire from the NHS and 27 (25%) would change hospital under these circumstances. Most consultants had experience in the major anaesthetic sub-specialties within the preceding 5 years (obstetrics 67%, ITU 81%, major trauma 91%). Consequently the need for retraining amongst consultant anaesthetists prior to resuming residential emergency duties would be low. When questioned about the impact on anaesthetic services, 67 (61%) felt the proposals would be detrimental whilst 23 (21%) felt there would be beneficial effects. Most consultants remain antagonistic toward the Calman proposals, with a reluctance to return to residential duties.