Influences of splanchnic nerve blockade on endocrine-metabolic responses to upper abdominal surgery

Epidural local anaesthetics versus opioid-based analgesic regimens for postoperative gastrointestinal paralysis, vomiting and pain after abdominal surgery

BACKGROUND

Gastrointestinal paralysis, nausea and vomiting and pain are major clinical problems following abdominal surgery. Anaesthetic and analgesic techniques that reduce pain and postoperative nausea and vomiting (PONV), while preventing or reducing postoperative ileus, may reduce postoperative morbidity, duration of hospitalization and hospital costs. This review was first published in 2001 and was updated by new review authors in 2016.

OBJECTIVES

To compare effects of postoperative epidural analgesia with local anaesthetics versus postoperative systemic or epidural opioids in terms of return of gastrointestinal transit, postoperative pain control, postoperative vomiting, incidence of anastomotic leak, length of hospital stay and costs after abdominal surgery.

SEARCH METHODS

We identified trials by conducting computerized searches of the Cochrane Central Register of Controlled Trials (CENTRAL) (2014, Issue 12), MEDLINE (from 1950 to December 2014) and EMBASE (from 1974 to December 2014) and by checking the reference lists of trials retained. When we reran the search in February 2016, we added 16 potential new studies of interest to the list of 'Studies awaiting classification' and will incorporate these studies into formal review findings during the next review update.

SELECTION CRITERIA

We included parallel randomized controlled trials comparing effects of postoperative epidural local anaesthetic versus regimens based on systemic or epidural opioids.

DATA COLLECTION AND ANALYSIS

We rated the quality of studies by using the Cochrane 'Risk of bias' tool. Two review authors independently extracted data and judged the quality of evidence according to the GRADE (Grades of Recommendation, Assessment, Development and Evaluation Working Group) scale.

MAIN RESULTS

We included 128 trials with 8754 participants in the review, and 94 trials with 5846 participants in the analysis. Trials included in the review were funded as follows: charity (n = 19), departmental resources (n = 8), governmental sources (n = 15) and industry (in part or in total) (n = 15). The source of funding was not specified for the other studies.Results of 22 trials including 1138 participants show that an epidural containing a local anaesthetic will decrease the time required for return of gastrointestinal transit as measured by time to first flatus after an abdominal surgery (standardized mean difference (SMD) -1.28, 95% confidence interval (CI) -1.71 to -0.86; high quality of evidence; equivalent to 17.5 hours). The effect is proportionate to the concentration of local anaesthetic used. A total of 28 trials including 1559 participants reported a decrease in time to first faeces (stool) (SMD -0.67, 95% CI -0.86 to -0.47; low quality of evidence; equivalent to 22 hours). Thirty-five trials including 2731 participants found that pain on movement at 24 hours after surgery was also reduced (SMD -0.89, 95% CI -1.08 to -0.70; moderate quality of evidence; equivalent to 2.5 on scale from 0 to 10). From findings of 22 trials including 1154 participants we did not find a difference in the incidence of vomiting within 24 hours (risk ratio (RR) 0.84, 95% CI 0.57 to 1.23; low quality of evidence). From investigators in 17 trials including 848 participants we did not find a difference in the incidence of gastrointestinal anastomotic leak (RR 0.74, 95% CI 0.41 to 1.32; low quality of evidence). Researchers in 30 trials including 2598 participants noted that epidural analgesia reduced length of hospital stay for an open surgery (SMD -0.20, 95% CI -0.35 to -0.04; very low quality of evidence; equivalent to one day). Data on costs were very limited.

AUTHORS' CONCLUSIONS

An epidural containing a local anaesthetic, with or without the addition of an opioid, accelerates the return of gastrointestinal transit (high quality of evidence). An epidural containing a local anaesthetic with an opioid decreases pain after abdominal surgery (moderate quality of evidence). We did not find a difference in the incidence of vomiting or anastomotic leak (low quality of evidence). For open surgery, an epidural containing a local anaesthetic would reduce the length of hospital stay (very low quality of evidence).

Neurolytic celiac plexus block reduces occurrence and duration of terminal delirium in patients with pancreatic cancer

PURPOSE

WHO's three step ladder sometimes cannot provide adequate pain relief for pancreatic cancer. Some patients develop terminal delirium (TD). The aim of this study was to test if the addition of a celiac plexus block (CPB) to pharmacotherapy could reduce the incidence of TD.

METHODS

Pancreatic cancer patients under the care of our palliative-care team were investigated with regard to the duration and occurrence of TD, pain scores [numerical rating score (NRS)] and daily opioid dose. Between August 2007 to September 2008, 17 patients received only pharmacotherapy (control group). Then, we modified our guideline for analgesia, performing CPB 7 days after the first intervention of our team. Between October 2008 to September 2009, 19 patients received CPB.

RESULTS

The opioid doses in CPB group were significantly lower both at 10 days after the first intervention (3 days after CPB) (27 ± 11 vs. 66 ± 82 mg; p = 0.029) and 2 days before death (37 ± 25 vs. 124 ± 117 mg; p = 0.009). NRS in the CPB group were significantly lower both at 10 days after the first intervention (0 [0-2] vs. 3 [2-5], p < 0.0001) and 2 days before death (1 [0-2] vs. 3 [1-4.5], p = 0.018). The occurrence and duration of TD in CPB group were both reduced (42 vs. 94 %, p = 0.019; and 1.8 ± 2.9 vs. 10.4 ± 7.5 days, p = 0.0003).

CONCLUSION

The duration and occurrence of TD and the pain severity were significantly less in pancreatic cancer patients who underwent neurolytic CPB.

The effect of celiac plexus block on heart rate variability

BACKGROUND

Celiac plexus block (CPB) can be used for treating intra-abdominal visceral pain syndromes. The celiac plexus is the largest plexus of the sympathetic nervous system. Several nerve blocks have a marked effect on autonomic nervous activity. Furthermore, stellate ganglion block changes cardiac autonomic nervous activity. Thus, CPB could influence the sympathetic activity of the cardiac plexus. The aim of the present study was to see whether CPB modulated heart rate variability (HRV) in patients with pancreatic cancer.

METHODS

Twelve patients received neurolytic CPB using 14 ml absolute alcohol. Data recorded in a palm-sized electrocardiographic unit were analyzed for HRV.

RESULTS

CPB using a neurolytic solution did not induce any significant changes in the low-frequency (LF)/high-frequency (HF) ratio of HRV (LF/HF, P = 0.4642). Furthermore, the procedure did not induce any significant changes in blood pressure (systolic, P = 0.5051; diastolic, P = 0.5180).

CONCLUSION

CPB did not induce any significant changes in HRV or hemodynamics.

Systemic Levels of Local Anaesthetic after Intra-Peritoneal Application – a Systematic Review

There is a lack of cohesive reports on the systemic levels of local anaesthetic after intraperitoneal application. A comprehensive systematic review with no language restriction was conducted. Eighteen suitable articles were identified. Data were compiled and presented according to local anaesthetic agent. Intraperitoneal local anaesthetic has been studied in many different procedures, including open and laparoscopic surgery. A total of 415 patients were included for analysis. There were no cases of clinical toxicity. There were 11 (2.7%) cases with a systemic level above or close to a safe threshold (as determined by the report authors) in three trials utilising intraperitoneal local anaesthetic after laparoscopic cholecystectomy. Intraperitoneal lignocaine doses varied from 100 to 1000 mg, mean Cmax ranged from 1.01 to 4.32 μg/ml and mean Tmax ranged from 15 to 40 minutes. Intraperitoneal bupivacaine doses varied from 50 to 150 mg (weight based doses also reported), mean Cmax ranged from 0.29 to 1.14 μg/ml and mean Tmax ranged from 15 to 60 minutes. Intraperitoneal ropivacaine doses varied from 100 to 300 mg, mean Cmax ranged from 0.66 to 3.76 μg/ml and mean Tmax ranged from 15 to 35 minutes. The addition of adrenaline to intraperitoneal local anaesthetic almost halves systemic levels and prolongs Tmax. Intraperitoneal local anaesthetic results in detectable systemic levels in the perioperative setting. Despite a lack of clinical toxicity, careful attention to dose is still required to prevent potential systemic toxic levels. Clinicians should also consider the addition of adrenaline to intraperitoneal local anaesthetic solutions to further add to the systemic safety profile.

Randomized controlled trial of preoperative oral carbohydrate treatment in major abdominal surgery

Background

Major surgery is associated with postoperative insulin resistance which is attenuated by preoperative carbohydrate (CHO) treatment. The effect of this treatment on clinical outcome after major abdominal surgery has not been assessed in a double-blind randomized trial.

Methods

Patients undergoing elective colorectal surgery or liver resection were randomized to oral CHO or placebo drinks to be taken on the evening before surgery and 2 h before induction of anaesthesia. Primary outcomes were postoperative length of hospital stay and fatigue measured by visual analogue scale.

Results

Sixty-nine and 73 patients were evaluated in the CHO and placebo groups respectively. The groups were well matched with respect to surgical procedure, epidural analgesia, laparoscopic procedures, fasting period before induction and duration of surgery. Postoperative changes in fatigue score from baseline did not differ between the groups. Median (range) hospital stay was 7 (2–35) days in the CHO group and 8 (2–92) days in the placebo group (P = 0·344). For patients not receiving epidural blockade or laparoscopic surgery (20 CHO, 19 placebo), values were 7 (3–11) and 9 (2–48) days respectively (P = 0·054).

Conclusion

Preoperative CHO treatment did not improve postoperative fatigue or length of hospital stay after major abdominal surgery. A benefit is not ruled out when epidural blockade or laparoscopic procedures are not used. Registration number: ACTRN012605000456651 (http://www.anzctr.org.au).

Large-Dose Intrathecal Sufentanil Prevents the Hormonal Stress Response During Major Abdominal Surgery: A Comparison with Intravenous Sufentanil in a Prospective Randomized Trial

We studied the effect of large-dose intrathecal sufentanil (ITS) for major abdominal surgery on the hormonal stress response. Forty patients were randomly allocated to receive either IV sufentanil (IVS) or 150 microg of ITS as part of general anesthesia. In the IVS group, adrenocorticotropic hormone (ACTH) and cortisol concentrations were larger than baseline and the ITS group, 60 min after incision and at skin closure. Plasma concentrations of cortisol and ACTH were not different from baseline in the ITS group during surgery. Six hours after skin closure, cortisol concentrations were larger than baseline in both groups. Twenty-four and 48 h after skin closure, ACTH and cortisol values were similar between groups. Norepinephrine concentrations increased after surgery in both groups. Blood glucose levels increased in both groups during and after surgery. Pain scores and morphine consumption during the first 48 h after surgery were lower in the ITS group. The data show that large-dose ITS prevents the intraoperative hormonal stress response in comparison with balanced anesthesia. We speculate that this is due to the highly specific binding of sufentanil to spinal and supraspinal receptors. This technique improves postoperative analgesia when compared with balanced anesthesia.

Reduction of postoperative mortality and morbidity with epidural or spinal anaesthesia: results from overview of randomised trials

OBJECTIVES

To obtain reliable estimates of the effects of neuraxial blockade with epidural or spinal anaesthesia on postoperative morbidity and mortality.

DESIGN

Systematic review of all trials with randomisation to intraoperative neuraxial blockade or not.

STUDIES

141 trials including 9559 patients for which data were available before 1 January 1997. Trials were eligible irrespective of their primary aims, concomitant use of general anaesthesia, publication status, or language. Trials were identified by extensive search methods, and substantial amounts of data were obtained or confirmed by correspondence with trialists.

MAIN OUTCOME MEASURES

All cause mortality, deep vein thrombosis, pulmonary embolism, myocardial infarction, transfusion requirements, pneumonia, other infections, respiratory depression, and renal failure.

RESULTS

Overall mortality was reduced by about a third in patients allocated to neuraxial blockade (103 deaths/4871 patients versus 144/4688 patients, odds ratio=0.70, 95% confidence interval 0.54 to 0.90, P=0. 006). Neuraxial blockade reduced the odds of deep vein thrombosis by 44%, pulmonary embolism by 55%, transfusion requirements by 50%, pneumonia by 39%, and respiratory depression by 59% (all P<0.001). There were also reductions in myocardial infarction and renal failure. Although there was limited power to assess subgroup effects, the proportional reductions in mortality did not clearly differ by surgical group, type of blockade (epidural or spinal), or in those trials in which neuraxial blockade was combined with general anaesthesia compared with trials in which neuraxial blockade was used alone.

CONCLUSIONS

Neuraxial blockade reduces postoperative mortality and other serious complications. The size of some of these benefits remains uncertain, and further research is required to determine whether these effects are due solely to benefits of neuraxial blockade or partly to avoidance of general anaesthesia. Nevertheless, these findings support more widespread use of neuraxial blockade.

Epidural local anaesthetics versus opioid-based analgesic regimens on postoperative gastrointestinal paralysis, PONV and pain after abdominal surgery

BACKGROUND

Gastrointestinal paralysis, nausea and vomiting, and pain, are major clinical problems following abdominal surgery. Anaesthetic and analgesic techniques that reduce pain and postoperative nausea and vomiting (PONV), and prevent or reduce postoperative ileus, may reduce postoperative morbidity, duration of hospitalisation and hospital costs.

OBJECTIVES

To compare effects of postoperative epidural local anaesthetic with regimens based on systemic or epidural opioids, on postoperative gastrointestinal function, postoperative pain, PONV and surgical/anaesthetic complications.

SEARCH STRATEGY

Trials were identified by computerised searches of the Cochrane Controlled Trials Register, MEDLINE, EMBASE and by checking the reference lists of trials and review articles.

SELECTION CRITERIA

Randomised controlled trials comparing the effects of postoperative epidural local anaesthetic with systemic or epidural opioids.

DATA COLLECTION AND ANALYSIS

Collected data included treatment in active (local anaesthetic) and control (opioid based) groups, time to first postoperative stool, time to first postoperative flatus, gastric emptying measured by the paracetamol absorption test, duration of the passage of barium sulphate, pain assessments, use of supplementary analgesics, nausea, vomiting and surgical/anaesthetic complications.

MAIN RESULTS

Most studies in this review involved a small number of patients. Furthermore half of the studies indicated a poor level of methodology in particular regarding blinding and report of withdrawals. Heterogeneity of included studies was substantial. Results consistently showed reduced time to return of gastrointestinal function in the epidural local anaesthetic group compared with groups receiving systemic or epidural opioid (37 hours and 24 hours, respectively). Postoperative pain was comparable. Two studies compared the effect of epidural local anaesthetic with a combination of epidural local anaesthetic and opioid on gastrointestinal function. One study favoured epidural local anaesthetic and one study was indifferent. A meta analysis of five of eight studies comparing the effect of epidural local anaesthetic with a combination of epidural local anaesthetic and opioid on postoperative pain, yielded a reduction in VAS pain scores (0-100 mm) on the first postoperative day of 15 mm, in favour of the combination. No significant differences in PONV were observed between epidural local anaesthetic and opioid based regimens.

REVIEWER'S CONCLUSIONS

Administration of epidural local anaesthetics to patients undergoing laparotomy reduce gastrointestinal paralysis compared with systemic or epidural opioids, with comparable postoperative pain relief. Addition of opioid to epidural local anaesthetic may provide superior postoperative analgesia compared with epidural local anaesthetics alone. The effect of additional epidural opioid on gastrointestinal function is so far unsettled. Randomized, controlled trials comparing the effect of combinations of epidural local anaesthetic and opioid with epidural local anaesthetic alone on postoperative gastrointestinal function and pain are warranted.

[Benefit-risk and monitoring modalities of different techniques and methods of postoperative analgesia]

This review aimed to determine the benefits-risks ratio of postoperative analgesia. The various agents usually used for intravenous postoperative analgesia (paracetamol, NSAID's, opioids), and the techniques for postoperative analgesia (PCA, epidural, perinervous block) are analysed. The rules proposed for the monitoring of postoperative analgesia are considered.

The role of the phrenic nerves in stress response in upper abdominal surgery

Previous studies have failed to demonstrate a block of the endocrine response to upper abdominal surgery by thoracic epidural analgesia. To clarify the bases for this failure, we compared the effects of epidural analgesia of different dermatome levels up to C8-T2 or C3-4. The patients who received general anesthesia alone showed significant increases of adrenocorticotropic hormone (ACTH) and arginine vasopressin (AVP) immediately after skin incision. The patients with C8-T2 blocked developed significant increases in these hormones, not after the skin incision, but after the intraabdominal procedure. Of the eight patients with C3-4 block, six developed no such responses throughout the study period. The responses of oxytocin (OXT) and prolactin (PRL) were more susceptible to epidural analgesia and were blocked at the C8-T2 level. Growth hormone (GH) showed no correlation with surgical procedures and epidural block. These findings indicate that the nociceptive neural information during upper abdominal surgery is conveyed by the sensory fibers included in both the thoracic and lumbar spinal nerves that innervate the abdominal wall and the intraabdominal viscera, and by the phrenic nerves that innervate the diaphragm. The rationale for postulating the involvement of the phrenic nerves can be referred to the embryonal descent of the diaphragm from the C3-5 myotomes that serves as the upper wall of the abdominal cavity.

Epidural analgesia shortens postoperative ileus after ileal pouch-anal canal anastomosis

PURPOSE

A retrospective study was conducted to determine whether epidural analgesia would speed recovery from postoperative ileus in patients undergoing ileal pouch-anal canal anastomosis.

METHODS

Among 85 patients who underwent proctocolectomy with ileal pouch-anal canal anastomosis at the Mayo Medical Center between January 1, 1991 and October 31, 1992, 44 were treated for postoperative pain with continuous infusion of epidural fentanyl citrate supplemented by intravenous morphine on request, while 41 controls were given only systemic morphine sulfate as needed.

RESULTS

The patients in the two groups were matched and similar with regard to preoperative and operative risk factors and postoperative morbidity. No operative mortality occurred. Epidural fentanyl analgesia resulted in less need for nasogastric suction and intravenous fluids, more rapid discharge of fecal content, more rapid return to oral intake, and shorter hospitalization.

CONCLUSION

Epidural analgesia with fentanyl citrate shortened postoperative ileus after proctocolectomy and ileal pouch-anal canal anastomosis.

Continuous coeliac plexus blockade plus intermittent wound infiltration with bupivacaine following upper abdominal surgery: a double-blind randomised study

In this double-blind trial, we observed the effect of intermittent wound infiltration with local anaesthetic plus continuous coeliac plexus blockade on postoperative pain relief, pulmonary function, the neuroendocrine and acute phase protein response following upper abdominal surgery. In Group A (n = 10) patients received bupivacaine intermittently into the wound and continuously into the coeliac plexus following an initial bolus. A total of 862.5 mg of bupivacaine was used over 12 h with no observed toxicity. Group B (n = 10) received equal volumes of saline. Although pain relief was poor in both groups, the bupivacaine group used less morphine postoperatively and had lower pain scores than the saline group 4 h after operation (P less than 0.05). Pulmonary function was significantly reduced in both groups with no statistical difference between the two. Significant reductions in serum glucose and cortisol were achieved (P less than 0.05), suggesting that afferent neural blockade was partially effective in attenuating the neuroendocrine response. However, the postoperative rise in interleukin-6 was not affected by this technique. It is concluded that total afferent neural blockade cannot be achieved with peripheral wound and coeliac plexus administration of relatively large doses of local anaesthetic during upper abdominal surgery.

[Epidural anesthesia and metabolic response to surgical stress]

Surgical stress leads to reproducible physiological metabolic and hormonal responses, characterized by on altered carbohydrate metabolism, a net loss of protein and an increased lipolysis. They are due to an increased secretion of catecholamines, ACTH, cortisol and cytokines. Epidural analgesia prevents the hyperglycaemic, cortisol and adrenocortical responses to surgery. The lipolysis and the loss of protein are also attenuated. This effect only occurs in lower abdominal surgery, with an epidural blockade extending from T4 to S5, carried out with local anesthetic agents and started before the skin incision. However, such a blockade abates, but does not suppress, the metabolic response to upper abdominal or thoracic surgery, probably because of persistent vagal afferences, the incomplete blockade of somatic afferents, and a stimulation of the diaphragm and peritoneal free nerve endings. Likewise, epidural morphine does not modify the intraoperative metabolic and hormonal responses. The main reason is most probably the failure of opioids to block the sympathetic system, as well as their insignificant effects on fast conducting fibers.

Interpleural catheter for analgesia after cholecystectomy: the surgical perspective

Sixteen otherwise healthy women undergoing cholecystectomy were randomized to receive postoperative analgesia either by continuous infusion of papaveretum (n = 8), or by continuous interpleural infusion of bupivacaine (n = 8). Postoperative pain was assessed by linear analogue and ventilatory capacity. Changes in body protein were measured by in vivo neutron activation analysis. Clinical course was also noted. Pain scores were significantly lower in the interpleural group over the first 48 h (P less than 0.02). Ventilatory capacity was also significantly better for the first 24 h (P less than 0.025). There was no evidence of shortened postoperative ileus; hospital stay and postoperative fatigue were similar for the two groups. Weight and protein losses over a 2 week period were similar in the two groups. It is concluded that the apparent advantages in patient comfort and mobility offered by interpleural infusion are most marked in the first 48 h postoperatively, with an advantage in ventilatory capacity over the first 24 h.

Comparison of the effects of continuous intrapleural vs epidural administration of 0.5% bupivacaine on pain, metabolic response and pulmonary function following cholecystectomy

Twenty patients undergoing elective cholecystectomy were prospectively randomised to receive either intrapleural (bolus 20 ml followed by 10 ml/h) or thoracic epidural (bolus 9 ml followed by 5 ml/h) bupivacaine 0.5% for 8 h postoperatively to assess the effect of these two techniques on pain, pulmonary function and the surgical stress response. As assessed by the visual analogue scale (VAS), both groups received good but not total pain relief. Both groups had a 50% reduction in forced expiratory volume (FEV1), forced vital capacity (FVC) and peak expiratory flow rate (PEFR) after operation, and there was no observed effect on the stress response as measured by plasma glucose and cortisol. It is concluded that while both techniques provide good analgesia, the degree and extent of nerve blockade are not sufficient to affect the afferent neurogenic stimuli responsible for the observed effects on pulmonary function and the stress response.

Influence of intraperitoneal anesthesia on pain and the sympathoadrenal response to abdominal surgery

The effects of intraperitoneal administration of bupivacaine on pain and the sympathoadrenal response to surgery were studied in a double-blind randomized trial in 19 patients undergoing cholecystectomy. Bupivacaine (2 mg/kg) was dissolved in 300 ml isotonic saline and administered into the peritoneal cavity 10 min before the operation (n = 9). Saline was administered in a comparable group of patients (n = 10). There were no significant differences in pain scores between the groups during the first day after surgery (P greater than 0.05). Postoperative requirements of pethidine during the first 2 days after surgery did not differ significantly between the groups. Blood glucose levels were significantly lower in the bupivacaine-treated group 1 h (P less than 0.05) and 4 h (P less than 0.05) after skin incision. No significant differences were observed between the groups regarding plasma catecholamine and serum cortisol levels during and after surgery. Differences between the groups regarding urine output of catecholamines during the first and second postoperative days were not significant. Our results suggest that single administration of a local anesthetic intraperitoneally does not reduce pain or the sympathoadrenal response to upper abdominal surgery.

Stress and the pituitary-adrenal axis

The hypothalamo-pituitary-adrenal axis is controlled by complex regulatory mechanisms. Numerous factors such as CRF, vasopressin, oxytocin, angiotensin II and conceivably other hormones--all controlled by various substances acting on central locations--stimulate the release of the stress hormone ACTH. On the other hand, glucocorticoids inhibit the secretion of ACTH by acting at the hypothalamic and/or pituitary level. The release of ACTH is therefore the final outcome of the interactions between the hypothalamus, the adrenal gland and possibly other organs. The multimolecular nature of the factors responsible for the control of the pituitary-adrenal axis is an attractive hypothesis because of the great variety of stress stimuli. The various factors could have specific roles in various stress situations. They provide a highly sensitive mechanism regulating very finely the stress hormone in response to a whole variety of endogenous and exogenous stimuli. Depending on the type of stress, they may therefore singly or in combination affect the amount and duration of ACTH and steroid secretion. The released glucocorticoids may then produce their numerous effects on inflammatory and immunological processes, carbohydrate metabolism, shock and water balance. It has been postulated that these effects may be important in order to prevent host responses from over-reacting to stress and threatening homeostasis. However, proof of the necessity of the glucocorticoid hypersecretion in response to stress remains elusive.

Role of the splanchnic nerves in endocrine and metabolic response to abdominal surgery

The splanchnic nerves are inevitably stimulated during upper abdominal surgery and this may produce various responses. To assess the role of splanchnic nerve stimulation on the endocrine-metabolic responses to abdominal surgery, intra-operative splanchnic nerve blockade was carried out in 12 patients undergoing elective gastrectomy under general anaesthesia and the results compared with those of patients undergoing gastrectomy under general anaesthesia or epidural analgesia alone. In the splanchnic blockade group, intra-operative increase in plasma cortisol, glucose, FFA (free fatty acids) and urinary adrenaline excretion were significantly less than that of the general anaesthesia group. This inhibitory effect of splanchnic blockade on these endocrine-metabolic responses was almost the same as, but slightly less remarkable than, that of high spinal epidural blockade. Urinary noradrenaline excretion reached the highest level on the first postoperative day in the general anaesthesia group. This noradrenaline response was significantly inhibited in the splanchnic group as well as in the epidural group. These results appeared to indicate that mechanical stimulation to the splanchnic nerve due to operative manipulation is largely responsible for the endocrine-metabolic responses in abdominal surgery. The results also suggested that, in addition to the splanchnic nerve stimulation, conscious pain perception is responsible for catecholamine release.