Propensity score-matched outcomes after thoracic epidural or paravertebral analgesia for thoracotomy.

It is not known which regional analgesic technique is most effective or safest after open lung resection. We retrospectively examined outcomes in 828 patients who received thoracic epidural analgesia and 791 patients who received paravertebral block after lung resection between 2008 and 2012. We analysed outcomes for 648 patients, 324 who had each analgesic technique, matched by propensity scores generated with peri-operative data. There were 22 out of 324 (7%) postoperative respiratory complications after thoracic epidural and 23 out of 324 (7%) after paravertebral block, p = 0.88. For any postoperative complication, there were 80 out of 324 (25%) and 78 out of 324 (24%) complications, respectively, p = 0.85. There were 17 out of 324 (5%) re-admissions to intensive care after thoracic epidural and 17 out of 324 (5%) after paravertebral block, p > 0.99, and the number of deaths before discharge were 6 out of 324 (2%) and 4 out of 324 (1%), respectively, p = 0.53. There was no significant difference in median (IQR [range]) hospital stay after thoracic epidural or paravertebral block, 6 (5-9 [2-94]) days vs. 6 (5-9 [2-122]), respectively, p = 0.83. Our study suggests that rates of complications as well as length of hospital stay after thoracic epidural analgesia and paravertebral blockade are similar. We were unable to compare analgesic efficacy due to incomplete data.

Randomized clinical trial to determine the effect of nasogastric drainage on tracheal acid aspiration following oesophagectomy.

BACKGROUND: The aim of this study was to investigate tracheal acid aspiration after oesophagectomy and to determine whether it is influenced by nasogastric (NG) drainage. METHODS: Thirty-four patients undergoing oesophagectomy were randomized to one of three methods of NG drainage: a single-lumen tube with free drainage and 4-hourly aspiration, a sump-type tube on continuous suction drainage, or no NG tube. A tracheal pH probe was used to collect information on acid aspiration for 48 h after surgery. A pH < 5.5 was considered abnormal (normal pH 6.8-7.2). Total time with tracheal pH < 5.5, number of reflux episodes and longest reflux time were compared between groups. RESULTS: There was significant and persistent tracheal acid aspiration in all patients. Patients with a sump-type tube had a significantly shorter total time with tracheal pH < 5.5 than those in the other groups (sump-type tube versus single-lumen tube, P = 0.0069; sump-type tube versus no tube, P = 0.0071). Patients randomized to no NG tube experienced more respiratory complications after surgery than those who had either single-lumen or sump-type tubes (seven of 12 versus four of 22 patients; P = 0.023). Insertion of a NG tube was necessary in the first week after surgery in seven of 12 patients in this group. CONCLUSION: Routine NG drainage after oesophagectomy is necessary. A sump-type NG tube is better at preventing tracheal acid aspiration and may reduce the incidence of respiratory complications.

The effect of gel lubrication on cuff leakage of double lumen tubes during thoracic surgery.

High-volume, low-pressure tracheal cuffs of disposable double lumen tubes may offer limited protection to the dependent lung if fluid leaks through folds in the inflated cuffs. This study was undertaken to determine the incidence of fluid leakage past the tracheal cuff and whether gel lubrication reduces the incidence. Fifty-five patients were randomly assigned to receive a double lumen tube with or without gel lubrication. The dependent lung was intubated. With the patient in the lateral position, methylthionium chloride was administered above the tracheal cuff via a pre-attached catheter. Fibreoptic bronchoscopy was performed to determine if dye had passed the tracheal cuff. Three patients were excluded. Dye leakage was seen in 12/27 and 3/25 patients in the unlubricated and lubricated group, respectively (p = 0.014). Gel lubrication significantly reduces fluid leakage past the tracheal cuff of a double lumen tube and should be considered for all thoracic surgical patients requiring one-lung ventilation.

Double-blind comparison of intrapleural saline and 0.25% bupivacaine for ipsilateral shoulder pain after thoracotomy in patients receiving thoracic epidural analgesia.

BACKGROUND: The aim of this prospective double-blind randomized placebo-controlled study was to investigate the effect of intrapleural bupivacaine on ipsilateral post-thoracotomy shoulder pain in patients receiving thoracic epidural analgesia. METHODS: Of the 68 patients recruited to the study, 41(60%) developed ipsilateral shoulder pain within 2 h of surgery. These patients were randomly assigned to receive either 40 ml of intrapleural bupivacaine 0.25% with epinephrine 1:200 000 or 40 ml of intrapleural saline. The study solution was injected into the tube of a basal drain that had been clamped distal to the site of administration. Shoulder pain at rest and on coughing was assessed using a visual analogue scale (VAS) and an observer verbal rating score (OVRS) immediately before and 30 min, 1 h, 2 h, 3 h and 4 h after intrapleural bupivacaine/saline. The total volume of epidural solution administered was recorded. RESULTS: Thirty-nine patients completed the study and were included in the analysis. There were no significant differences in baseline characteristics between the two groups. There were no significant differences between groups for VAS or OVRS pain scores at rest or with cough at any of the six assessment times. The total volumes of epidural solution administered to the bupivacaine and saline groups were 56 ml and 48 ml, respectively. This difference was not significant. CONCLUSION: Intrapleural administration of 40 ml of bupivacaine 0.25% does not provide effective pain relief for ipsilateral post-thoracotomy shoulder pain.

Infection control measures for adult cardiac surgery in the UK--a survey of current practice.

The aim of the study was to define current UK practice for antimicrobial prophylaxis and preoperative screening for bloodborne viruses and methicillin-resistant Staphylococcus aureus (MRSA) before routine cardiac surgery. An e-mail survey was sent to the Association of Cardiothoracic Anaesthetists (ACTA) Linkmen in all 36 UK adult cardiac surgical units, during May 2001. Questions were asked regarding MRSA, hepatitis B, C and human immunodeficiency virus (HIV) screening. Regarding antimicrobial prophylaxis questions were asked regarding agent(s), dose, frequency and duration of use for coronary artery and value surgery. Responses were received from 29 units (response rate 81%). There was a wide variety of practices for all units surveyed. For MRSA screening, 19 units (65%) screened all patients before surgery, but two (7%) screened none, with the remaining eight units (28%) screening selected high-risk groups. Regarding screening for bloodborne viruses: eight units (28%) tested all patients routinely for hepatitis B, 11 units (39%) selectively tested only high-risk patients and transplant recipients. No units tested for hepatitis C and HIV infection routinely. All units used prophylactic antibiotics routinely, but the type and number of agents, along with dose and duration of therapy all varied widely. For coronary artery bypass graft (CABG) surgery, a single agent was used by 16 units (55%), two agents by 12 units (41%) and three agents by one unit (4%). There is a wide variation in infection control practice in adult cardiac units throughout the UK. Rationalization of preoperative screening and use of prophylactic antibiotics, by adopting nationally agreed practice guidelines, could significantly reduce costs and potentially reduce the incidence of resistant organisms.

Gastric emptying in post-thoracotomy patients receiving a thoracic fentanyl-bupivacaine epidural infusion.

BACKGROUND AND OBJECTIVE: The effect of anaesthesia and surgery on gastric emptying is not constant, and this has not been previously studied in patients undergoing thoracotomy for lung resection with a bupivacaine-fentanyl epidural infusion for analgesia. There are important implications in this group of patients with regards to the recommencement of important oral medication as well as the risks of aspiration of gastric contents. The study examined gastric emptying in these patients until the second postoperative day. METHODS: In a prospective repeated measures study, the effect of fentanyl-bupivacaine epidural analgesia at the mid-thoracic level on gastric emptying was assessed in 11 patients undergoing thoracotomy for lung resection. Gastric emptying was measured using a paracetamol absorption technique. Patients acted as their preoperative controls and were assessed 4 h postoperatively and on the second postoperative day. RESULTS: The mean (SEM) maximum plasma paracetamol concentration was 204.6 (20.4) micromol L(-1) before operation, 61 (9.5) micromol L(-1) 4 h postoperatively and 114.3 (22.6) micromol L(-1) on the second postoperative day. Mean (SEM) paracetamol absorption at 120 min was 15,638 (1441) micromol min L(-1) preoperatively, 5731 (821) micromol min L(-1) 4 h postoperatively and 9325 (1759) micromol min L(-1) on the second postoperative day. Postoperative values were significantly (P < 0.005) less than the preoperative values. CONCLUSIONS: After thoracotomy, gastric emptying was delayed until at least the second postoperative day in patients receiving mid-thoracic fentanyl-bupivacaine epidural analgesia.

Isoflurane and coronary heart disease.

Early studies indicated that isoflurane caused coronary steal and should therefore be avoided in patients with coronary heart disease. Subsequently, more detailed trials have disputed this and have shown that as long as coronary perfusion pressure is maintained, isoflurane does not cause coronary steal or myocardial ischaemia. There is now growing evidence, initially in animal work but more recently in human studies, that isoflurane has myocardial protective properties, limiting infarct size and improving functional recovery from myocardial ischaemia. The mechanism for this protection mimics ischaemic preconditioning and involves the opening of adenosine triphosphate-dependent potassium channels. The few studies comparing the myocardial protection offered by individual anaesthetic agents indicate that isoflurane represents the anaesthetic agent of choice for patients with coronary heart disease.

Use of low dose arginine vasopressin to support brain-dead organ donors.

In a prospective study, we documented the hemodynamic effects of conventional donor maintenance in 24 brain-dead organ donors. Patients were then randomized to receive either saline or a low dose arginine vasopressin (AVP) infusion. In the AVP group (n = 11), plasma hyperosmolality decreased (P < 0.05), blood pressure increased (P < 0.01), inotrope use decreased (P < 0.01), and cardiac output was maintained. In the control group (n = 13), plasma hyperosmolality increased (NS); no significant change in blood pressure, cardiac output, or inotrope infusion rate occurred. Myocardial ATP levels were higher in the AVP than the control group (NS). Early organ function was similar in the 2 groups. We conclude that the use of a low dose AVP infusion enables inotrope use to be reduced and recommend consideration be given to the use of a low dose AVP infusion in potential thoracic organ donors.

Haemodynamic responses to surgery in brain-dead organ donors.

In a prospective study we documented the haemodynamic response to surgery in 14 brain-dead organ donors. The haemodynamic responses to the first 30 min of surgery were predominantly due to alterations in vascular resistance. The mean systemic vascular resistance increased significantly (p = < 0.01) from 936 to 1217 dyn.s.cm-5 after 6 min, then decreased significantly (p = < 0.001) to 642 dyn.s.cm-5 after 30 min of surgery. In two patients, the decrease in systemic vascular resistance was associated with haemodynamic decompensation. The left cardiac work index increased significantly (p = < 0.05) during surgery. We conclude that retrieval surgery causes significant haemodynamic effects. The early effects are predictable and may jeopardise organ perfusion. We advance arguments that organ preservation may be compromised by the use of inotropic agents. When practical, we suggest that a pulmonary artery catheter should be used during retrieval surgery in multi-organ donors to facilitate a reduction in the use of inotropic drugs.