The impact of increasing the use of regional anaesthesia for emergency caesarean section

BACKGROUND AND OBJECTIVE

In 1991 general anaesthesia was used extensively for emergency Caesarean section at Haukeland University Hospital even in patients with an ongoing epidural infusion. With increased knowledge of the potential safety benefits of regional anaesthesia and increased experience with the technique, we decided to use indwelling epidural catheters for emergency Caesarean section.

METHODS

We conducted a retrospective analysis of a full annual data set on emergency Caesarean section in parturients with ongoing epidural analgesia in 1997 and compared it with a similar data set from 1991.

RESULTS

Epidural anaesthesia was used significantly more often in 1997 with 115 (78%) cases than in 1991 with five (12%) cases (P < 0.001). Elapsed time before adequate anaesthesia and the start of surgery was significantly shorter in 1991 (mean 8.3 min) compared to 1997 (mean 13 min) (P < 0.001). No deaths or major complications were observed in either group. Intraoperative minor complications were observed more frequently in 1997 with 70 cases (47%) than in 1991 with two cases (6%) (P < 0.001). The principal complications were hypotension and nausea. Postoperative complications in mother and neonate were similar in both groups. There was a significantly shorter mean hospital stay in 1997 (6 days), compared with 1991 (8 days) (P < 0.001).

CONCLUSION

The increase in the use of indwelling epidural catheters for emergency Caesarean section has resulted in a significant increase in the use of regional anaesthesia. A modest increase in time elapsed before start of surgery was observed although there were no significant differences in the number of neonates with low Apgar scores. No major complications were observed, but there was an increased frequency of minor complications in 1997.

Increased spillover of norepinephrine to the portal vein during CO-pneumoperitoneum in pigs

BACKGROUND

Elevated intra abdominal pressure (IAP) during CO2-insufflation has been associated with increased catecholamine concentrations in plasma. We have previously indicated that this may be due to a regional increased spillover from the abdominal region. In this experimental study we investigated catecholamine spillover from the drainage area of the portal vein during CO2-pneumoperitoneum.

METHODS

Eight pigs under general anesthesia were investigated before and after CO2-pneumoperitoneum with an IAP of 15 mmHg. Regional spillover of catecholamines was determined by measuring plasma catecholamine concentrations and flow simultaneously. Plasma concentrations of catecholamines were measured from the portal and femoral veins, the pulmonary and carotid arteries. Flow data were collected with laser-Doppler transit time flow probes around the portal and femoral veins. Cardiac output was measured by the thermo-dilution technique. Estimated spillover was calculated by the veno-arterial difference multiplied by flow.

RESULTS

We found a significant increase in estimated spillover of norepinephrine from the drainage area of the portal vein from 10 (-1.2, 78) ng x min(-1) to 27 (1.8, 475) ng x min(-1)[median (range)] (P = 0.05), but no change in estimated spillover of norepinephrine from the drainage area of the femoral vein. Plasma concentrations of norepinephrine increased in central venous and arterial blood. There was no significant change in epinephrine concentrations in arterial blood.

CONCLUSION

Estimated norepinephrine spillover from the drainage area of the portal vein increased during CO2-pneumoperitoneum in pigs. This may indicate that the increased norepinephrine concentrations found in arterial plasma reflects a local activation of sympathetic nerves in the region of the portal drainage area.

Bispectral index, serum drug concentrations and emergence associated with individually adjusted target-controlled infusions of remifentanil and propofol for laparoscopic surgery

BACKGROUND

Target-controlled infusions (TCI) are used to simplify administration and increase precision of i.v. drugs during general anaesthesia. However, there is a limited relationship between preset targets and measured concentrations of drugs and between measured concentrations and measures of brain function, such as the bispectral index (BIS).

METHODS

We set out to evaluate the performance of TCI devices for propofol (Diprifusor) and remifentanil (Remifusor, prototype), during laparoscopic cholecystectomy in 21 patients. We also checked if there was any correlation between serum concentrations of propofol and BIS during individually adjusted anaesthesia.

RESULTS

The Diprifusor and Remifusor had a median absolute performance error of 60% and 25% respectively. Propofol concentrations were underpredicted by a median of 60%, and remifentanil concentrations were slightly overpredicted by a median of 7%. When anaesthesia was adjusted to keep BIS values between 45 and 60, no correlation existed between measured concentrations of propofol and the corresponding BIS values, although both BIS and serum propofol concentration discriminated well between the awake and asleep states. Emergence was rapid and uneventful in all patients. Female patients had a more rapid emergence than male patients (6.6 and 11.6 min respectively).

CONCLUSIONS

TCI devices for remifentanil and propofol result in large variation in measured serum concentrations. The lack of correlation between BIS and serum concentrations of propofol adds to the debate about whether BIS measures hypnosis as a graded state during surgery. This study confirms that women wake up faster than men, but provides no explanation for this repeatedly shown difference.

Cognitive dysfunction after minor surgery in the elderly

BACKGROUND

Major surgery is frequently associated with postoperative cognitive dysfunction (POCD) in elderly patients. Type of surgery and hospitalization may be important prognostic factors. The aims of the study were to find the incidence and risk factors for POCD in elderly patients undergoing minor surgery.

METHODS

We enrolled 372 patients aged greater than 60 years scheduled for minor surgery under general anesthesia. According to local practice, patients were allocated to either in- (199) or out-patient (173) care. Cognitive function was assessed using neuropsychological testing preoperatively and 7 days and 3 months postoperatively. Postoperative cognitive dysfunction was defined using Z-score analysis.

RESULTS

At 7 days, the incidence (confidence interval) of POCD in patients undergoing minor surgery was 6.8% (4.3-10.1). At 3 months the incidence of POCD was 6.6% (4.1-10.0). Logistic regression analysis identified the following significant risk factors: age greater than 70 years (odds ratio [OR]: 3.8 [1.7-8.7], P = 0.01) and in- vs. out-patient surgery (OR: 2.8 [1.2-6.3], P = 0.04).

CONCLUSIONS

Our finding of less cognitive dysfunction in the first postoperative week in elderly patients undergoing minor surgery on an out-patient basis supports a strategy of avoiding hospitalization of older patients when possible.

Regional anaesthesia in ambulatory surgery

PURPOSE OF REVIEW

The purpose of this review is to present recent research into the clinical use of regional anaesthesia techniques in ambulatory surgery. Further, to put into an ambulatory perspective some of the issues recently discussed on the basis and practice of regional anaesthesia in general.

RECENT FINDINGS

Early discharge with long-acting peripheral nerve blockade seems safe, and discharge of patients who have not voided after surgery is possible under specified terms. The spinal anaesthesia technique may be improved in terms of better and faster recovery characteristics if the dose of local anaesthesia is reduced by adding a small dose of opioid.

SUMMARY

Loco-regional techniques are well suited for ambulatory surgery due to less postoperative nausea and pain and possibly less cognitive dysfunction. The different techniques are continuously being refined in order to provide fast discharge readiness, while still maintaining the benefits.

Does anaesthesia cause postoperative cognitive dysfunction? A randomised study of regional versus general anaesthesia in 438 elderly patients

BACKGROUND

Postoperative cognitive dysfunction (POCD) is a common complication after cardiac and major non-cardiac surgery with general anaesthesia in the elderly. We hypothesized that the incidence of POCD would be less with regional anaesthesia rather than general.

METHODS

We included patients aged over 60 years undergoing major non-cardiac surgery. After giving written informed consent, patients were randomly allocated to general or regional anaesthesia. Cognitive function was assessed using four neuropsychological tests undertaken preoperatively and at 7 days and 3 months postoperatively. POCD was defined as a combined Z score >1.96 or a Z score >1.96 in two or more test parameters.

RESULTS

At 7 days, POCD was found in 37/188 patients (19.7%, [14.3-26.1%]) after general anaesthesia and in 22/176 (12.5%, [8.0-18.3%]) after regional anaesthesia, P = 0.06. After 3 months, POCD was present in 25/175 patients (14.3%, [9.5-20.4%]) after general anaesthesia vs. 23/165 (13.9%, [9.0-20.2%]) after regional anaesthesia, P = 0.93. The incidence of POCD after 1 week was significantly greater after general anaesthesia when we excluded patients who did not receive the allocated anaesthetic: 33/156 (21.2%[15.0-28.4%]) vs. 20/158 (12.7%[7.9-18.9%]) (P = 0.04). Mortality was significantly greater after general anaesthesia (4/217 vs. 0/211 (P < 0.05)).

CONCLUSION

No significant difference was found in the incidence of cognitive dysfunction 3 months after either general or regional anaesthesia in elderly patients. Thus, there seems to be no causative relationship between general anaesthesia and long-term POCD. Regional anaesthesia may decrease mortality and the incidence of POCD early after surgery.

Catecholamine release during laparoscopic fundoplication with high and low doses of remifentanil

BACKGROUND

Reports on stress responses to laparoscopic surgery have been conflicting. Depth of anesthesia may influence the neuro-hormonal release, including catecholamines. Opioids depress general sympathetic activation in a dose-dependent manner. We investigated the hypothesis that remifentanil would depress the catecholamine response to pneumoperitoneum and laparoscopic surgery differently with a high dose (HD) compared with a low dose (LD).

METHODS

In a randomized, prospective study we investigated 18 ASA I-II patients undergoing laparoscopic fundoplication with an intra-abdominal pressure of 12 mmHg. The patients were randomized to receive either a LD (0.13 microg kg-1x min-1) or HD (0.39 microg kg-1 x min-1) of remifentanil with a target-controlled infusion (TCI) technique. Bispectral index of EEG (BIS) was maintained at 40-55 by propofol delivered by a TCI system. Arterial catecholamines were analyzed at different times during the procedure.

RESULTS

Norepinephrine increased equally in both groups during pneumoperitoneum and surgical intervention. Epinephrine stayed low in the HD-group, while increasing during surgery in the LD-group.

CONCLUSION

High dose of remifentanil depressed the epinephrine response to pneumoperitoneum and surgery, indicating no general activation of the sympathetic nervous system. Neither a LD nor HD of remifentanil depressed the norepinephrine response during pneumoperitoneum. This suggests a centrally independent release of norepinephrine.

Ondansetron disintegrating tablets of 8 mg twice a day for 3 days did not reduce the incidence of nausea or vomiting after laparoscopic surgery

BACKGROUND AND OBJECTIVE

Although many antiemetic drugs are available for intravenous use in the hospital setting, few are available after patient discharge. Consequently, nausea and vomiting are frequent complaints from patients at home after ambulatory surgery. We tested the hypothesis that the new 8 mg ondansetron disintegrating tablets will decrease the rate of nausea and vomiting at home after laparoscopic surgery.

METHODS

Ninety-six patients were studied in a randomized double-blind study. Starting the first evening after operation and continuing every 12 h for 3 days, patients received either placebo or ondansetron 8 mg disintegrating tablets orally. The patients returned a questionnaire about postoperative nausea and vomiting, other side-effects, e.g. dizziness, headache, nightmare, anxiety and pain, as well as their overall satisfaction at 24 and 72 h after completion of surgery.

RESULTS

The rates of nausea and vomiting were similar in the two groups, both during the first 24 h (28 versus 48%, placebo and ondansetron, respectively (ns) and during the 24-72 h (21 versus 35% (ns)). The incidence rate of vomiting was 8% (placebo) versus 12% (ondansetron) during the first 24 h (ns) and 9 versus 13% respectively in the 24-72 h (ns). No difference between groups was observed in overall satisfaction, incidence of postoperative pain or other side-effects.

CONCLUSIONS

The use of ondansetron disintegrating tablets of 8 mg twice a day for 3 days did not reduce the incidence of nausea and vomiting in patients undergoing outpatient laparoscopic surgery.

[Outpatient laparoscopic fundoplication for gastroesophageal reflux disease]

BACKGROUND

Day-case laparoscopic fundoplication for gastro-oesophageal reflux disease was introduced in January 1997.

MATERIAL AND METHODS

Inclusion criteria were ASA grade 1-2, living within 30 minutes by car from the hospital, or staying over in the patient hotel the first night, with company. Initially, only selected patients were offered day-case treatment; later it was adopted as routine. The patients underwent general intravenous anaesthesia with propofol and remifentanil and were given prophylaxis against postoperative pain and nausea. The surgical procedure was Nissen-Rossetti fundoplication or semifundoplication.

RESULTS

83 patients were included. Ten patients were admitted, 73 (88%) were discharged as planned 3-8 hours after the operation. Eight patients (10%) were readmitted; one of them underwent reoperation for necrosis of the gastric fundus. Eight patients visited the outpatient department without need for readmission. At seven-day follow-up, 55 discharged patients (75%) were satisfied with the day-case treatment, nine (12%) were indifferent, and nine (12%) were dissatisfied, mostly because of pain. If offered a similar operation in the future, 50 patients (68%) would have preferred and 11 (15%) would have accepted day-case treatment; 12 (16%) would not.

INTERPRETATION

Outpatient laparoscopic fundoplication is safe and well tolerated by the majority of patients.

Guidelines for the practice of anesthesia in Norway

Since the first version saw the light of day in 1991 the Guidelines have occupied a central position in the Norwegian practice of anesthesia. This document comprises part of the quality management documents held in the departments of anesthesia in Norwegian hospitals. If departments of anesthesia are unable to adhere to certain specific points in the Guidelines, it is recommended that this should be documented in writing. It has been stated by central governmental bodies and patients' insurance organizations that the Guidelines will be an important factor in medico legal cases, although it is not an obligatory legal document for hospital owners. It is our objective that the document will form the foundation for quality assurance work in the departments of anesthesia in Norway. The purpose of this document is to ensure a satisfactory standard for the practice of anesthesia in Norway. 'The Guidelines for the Practice of Anesthesia in Norway' (the Guidelines) is a series of recommended guidelines. The practice of anesthesia in this context includes general anesthesia, regional anesthesia, controlled sedation, postoperative monitoring, and other observations where anesthesia personnel are required. The Guidelines apply to all doctors, nurses, and other personnel undertaking the delegated practice of anesthesia. Deviations from the Guidelines should be explained and documented in every case. The Guidelines should be adhered to in medical emergencies as far as possible. The Guidelines must not be allowed to prevent the execution of immediate and lifesaving measures. The Guidelines should be revised at regular intervals so that it is up-to-date with current legislation and medical and technological developments and practice.

Improved long-lasting postoperative analgesia, recovery function and patient satisfaction after inguinal hernia repair with inguinal field block compared with general anesthesia

BACKGROUND

Inguinal hernia repair is a common surgical procedure, and different types of anesthetic techniques are in use. We wanted to test if preoperative inguinal field block (IFB) with ropivacaine would provide benefits in the postoperative period compared with general anesthesia and wound infiltration.

METHODS

Sixty patients scheduled for inguinal hernia repair were randomized to receive general anesthesia with wound infiltration postoperatively, or inguinal field block (IFB) before surgery, with no or only light sedation intraoperatively. General anesthesia was induced with midazolam, fentanyl and propofol, maintained with propofol and alfentanil, and supplemented with nitrous oxide in oxygen through a laryngeal mask. The IFB was performed by an anesthesiologist, with 50-60 ml ropivacaine and 5 mg/ml with a dedicated technique.

RESULTS

All significant differences were in favor of the IFB group: less pain (visual analog scale, verbal pain score) postoperatively and until day 7, faster mobilization with less pain, lower analgesic consumption, and higher patient satisfaction.

CONCLUSION

Preoperative inguinal field block for hernia repair provides benefits for patients in terms of faster recovery, less pain, better mobilization and higher satisfaction throughout the whole first postoperative week.

Wound infection in day-surgery

To determine the surgical wound infection rate associated with day-surgery and to assess whether infection was related to patient factors, a prospective study of all electively operated adult day-cases was carried out during a 6 month period between January and June 1996. The study included gastroenterological orthopaedic, vascular, plastic and urological surgery. No operations involving obviously infected patients were performed in the unit. Strict criteria for diagnosis of infection were used. All patients were examined on the 7th and 30th post-operative day. A total of 642 (98.8%) patients were included (316 females 334 males). Infection developed in 22 of the 642 patients (3.5%), only three were diagnosed before the 7th day visit. Orthopaedic procedures accounted for more than 40% of the surgery, but only 22.7% of the wound infections. Gastroenterology made up nearly 36% of the procedures and accounted for 36.4% of the infections. Vascular procedures were 5.7% of the total but accounted for 18% of the infections. No correlation was found between age, gender, operation time or ASA-group and the infection rate. The study is to small to quantify with statistical significance risk-factors associated with wound infection in ambulatory surgery. Our data may suggest that the type of surgery as well as individual factors associated with surgeons may influence the wound infection rate.

Day-case laparoscopic fundoplication for gastro-oesophageal reflux disease

BACKGROUND

Based on a series of successful outpatient laparoscopic cholecystectomies, day-case laparoscopic fundoplication for gastro-oesophageal reflux disease was introduced in January 1997. The initial results are reported.

METHODS

Inclusion criteria were American Society of Anesthesiologists grade I-II, living within 30 min travel from the hospital, and adult company at home. Initially only selected patients were offered day-case treatment, but later it was adopted as routine. The patients underwent general intravenous anaesthesia with propofol and remifentanil, and were given ketorolac, propacetamol, droperidol and ondansetron as prophylaxis against postoperative pain and nausea. The surgical procedure was Nissen-Rosetti fundoplication or semifundoplication depending on oesophageal manometric results.

RESULTS

Forty-five patients were included. Four patients were admitted; 41 were discharged as planned 3-8 h after operation, and five of these patients were readmitted. One underwent reoperation for necrosis of the gastric fundus. A further five patients visited the outpatient department without need for admission. At follow-up 31 patients were satisfied with the day-case treatment, five were indifferent, and five were dissatisfied because of pain. If offered a similar operation in the future, 26 patients would have preferred and seven would have accepted day-case treatment, and eight would not.

CONCLUSION

Outpatient laparoscopic fundoplication is safe and well tolerated by the majority of patients.