Continuous epidural anaesthesia for major abdominal surgery in young children

The benefits of epidural anaesthesia combined with general anaesthesia were studied in young children scheduled for major abdominal surgical procedure (pull-through for Hirschsprung's disease). Two groups of nine children were studied receiving, respectively, general anaesthesia or general anaesthesia plus epidural anaesthesia. In the group receiving both general and regional anaesthesia, a polyurethane 24 G catheter was inserted via a Tuohy needle 19 G into the lumbar epidural space after induction of anaesthesia and intubation and bupivacaine, 0.25%, was injected epidurally (mean initial volume 0.71 +/- 0.04 ml kg-1). No opiates were needed during operation on the children in this group. After epidural anaesthesia, heart rate decreased significantly but systolic blood pressure remained unchanged. During surgery mean values of both heart rate and systolic blood pressure were significantly lower in the regional analgesia group compared to the general anaesthesia group. The need for blood replacement was also significantly lower, whereas pre- and post-operative haematocrit values were not significantly different. Administration of fluid and electrolytes during operation was also similar in both groups. A combination of epidural and general anaesthesia avoids the use of opiates during surgery, provides excellent per- and post-operative analgesia, allows a rapid and safe recovery, and facilitates the nursing of young children.     

Haemodynamic effects of induction of general anaesthesia with propofol during epidural anaesthesia

PURPOSE: To clarify whether propofol administration during thoracic or lumbar epidural anaesthesia intensifies the haemodynamic depression associated with epidural anaesthesia. METHODS: Patients (n = 45) undergoing procedures of similar magnitude were randomly divided into three study groups: a control group (n = 15) receiving general anaesthesia alone and two study groups undergoing thoracic (n = 15) and lumbar epidural anaesthesia (n = 15) before induction of general anaesthesia. All patients received 2 mg.kg-1 propofol at a rate of 200 mg.min-1, followed by a continuous infusion of 4 mg.kg-1.hr-1. Mean arterial blood pressure (MAP) and heart rate (HR) were measured at baseline, three minutes after induction, and one minute after tracheal intubation in all three groups and at 20 min after epidural anaesthesia was established in the thoracic and lumbar groups. RESULTS: Following epidural anaesthesia, MAP decreased from 94 +/- 14 (SD) at baseline to 75 +/- 11 mmHg (P < 0.0001) in the thoracic group and from 92 +/- 12 to 83 +/- 15 mmHg in the lumbar group. After propofol administration, MAP decreased further in the thoracic group to 63 +/- 9 mmHg (P = 0.0077) and to 67 +/- 10 mmHg (P = 0.0076) in the lumbar group. The MAP following propofol induction in the thoracic group (P < 0.0001) and in the lumbar group (P = 0.0001) was lower than MAP in the control group (81 +/- 9 mmHg). HR decreased only in response to thoracic epidural anaesthesia (P = 0.0066). CONCLUSION: The hypotensive effects of propofol are additive to those of epidural anaesthesia, resulting in a profound decrease in mean arterial pressure.     

Anaesthesia for endoluminal repair of abdominal aortic aneurysms

An audit of 100 patients undergoing elective abdominal aortic surgery either by open aortic repair (OAR group 50 patients) or endovascular aortic repair (EAR group 50 patients) was undertaken to document changes in anaesthetic technique and perioperative outcome. The data for the OAR group was collected retrospectively and thatfor the EAR group prospectively. Combined general anaesthesia and thoracic epidural anaesthesia was used in 44 of the OAR group whereas lumbar central neural blockade alone was used in 47 of the EAR group. The major differences between the two groups were that intraoperative blood loss was significantly less in the EAR group (OAR 1,674 +/- 1,008 ml, EAR 459 +/- 350 ml, P<0.001) and that no patient in the EAR group required admission to the Intensive Care Unit (ICU), whereas ICU time for the OAR patients was 29 +/- 22 hours. Hospital stay was also significantly different between the two groups (OAR 13 +/- 6 days, EAR 5 +/- 3 days, P<0.001). Major complications occurred in 20patients in the OAR group but only 4patients in the EAR group (P<0.001). EAR reduces blood loss, the requirement for ICU admission, and hospital stay. Central neural blockade is a satisfactory anaesthetic technique for EAR.     

Effect of pre-operative metoprolol on cardiovascular and catecholamine response and bleeding during hysterectomy.

The effect of a pre-operative dose of metoprolol on the catecholamine and cardiovascular responses to tracheal intubation and surgery, cardiac complications and intra-operative blood loss, were studied in patients undergoing elective hysterectomy during general anaesthesia. The study was double-blind and placebo controlled. The patients received metoprolol 100 mg or placebo orally 1-25 h before anaesthesia. In patients given metoprolol, heart rate and mean arterial pressure were lower during the first 45 min of anaesthesia. Plasma adrenaline and noradrenaline concentrations increased in both groups in response to tracheal intubation and surgery, but were higher after metoprolol. The incidence of arrhythmias was less after metoprolol. The mean operative blood loss was greater in the placebo group (486 +/- 170 ml (SEM) compared to 231 +/- 43 ml (SEM) after metoprolol). We conclude that oral premedication with metoprolol attenuates the hypertensive response to tracheal intubation and reduces both arrhythmias and operative blood loss.     

Epidural vs general anaesthesia and leg blood flow in patients with occlusive atherosclerotic disease

Total leg blood flow (plethysmography), skin blood flow (laser-Doppler flowmetry), and haemodynamic stability (MAP, HR, RPP) were studied in vascular (ABI less than 1.0; n = 31) and in non-vascular (ABI greater than 1.0; n = 24) surgical patients during epidural or fentanyl-supplemented general anaesthesia. During epidural anaesthesia significant increases in total leg blood flow were observed in vascular (from 1.9 +/- 0.2 to about 3 ml/100 ml tissue/min) as well as in non-vascular (from 2.5 +/- 0.6 to about 7 ml/100 ml tissue/min) patients and leg blood flow remained high in the postanaesthetic period. During general anaesthesia total leg blood did not increase, either in vascular or in non-vascular patients, and in the postanaesthetic period blood flow values even lower than the initial ones were observed. Skin blood flow increased about 4-fold in vascular as well as in non-vascular patients following both types of anaesthesia. In the immediate postanaesthetic period low flow values were again observed but only in the general anaesthesia groups. In vascular patients no critical redistribution of blood flow within the limb was observed irrespective of the type of anaesthesia. Good haemodynamic stability could only be maintained in the epidural group. It is concluded that epidural anaesthesia seems to offer considerable advantages over general anaesthesia for high-risk vascular patients during arterial reconstructions since better haemodynamic stability and higher leg blood flow can be achieved.     

Comparison of epidural and spinal blockade with 0.5% bupivacaine for transurethral surgery

The suitability of spinal versus epidural blockade for transurethral resection of the prostate was studied in 60 patients randomly allocated to spinal and epidural anaesthesia groups. 0.5% bupivacaine (Marcain, Astra, Sweden) was injected at the L3-L4 interspace, the dose being 3 ml in the spinal group and 19 (16-25) ml in the epidural group. The blood pressure decreased similarly after both epidural and spinal injections, but the heart rate was not significantly altered. No statistically significant differences were found between the groups in any of the variables measured, including blood pressure, heart rate, intraoperative blood loss and per- and post-operative complications. However, altogether eight patients in the epidural group, but none in the spinal group, had to be treated because of hypotension (P less than 0.001). The main advantage of the spinal blockade was a faster and more reliable blockade of the lowest sacral segments, and the main advantage of the epidural blockade was a less pronounced and shorter duration of motor blockade.     

Haemodynamic effects of thoracic epidural anaesthesia during induction of anaesthesia: an investigation into the effects of tracheal intubation during target-controlled infusion of propofol

We compared haemodynamic changes following induction of anaesthesia with propofol during tracheal intubation with and without epidural anaesthesia. Nineteen patients were divided into two groups to receive epidurally administered saline (Group C) or lidocaine 1.5% (Group E). The propofol infusion was started to produce blood concentrations of 3 microg.ml(-1), and following fentanyl and vecuronium administration, tracheal intubation was performed. Mean arterial blood pressure (MBP), heart rate (HR), Bispectral index and effect-site propofol concentration were recorded. Time to loss of consciousness was significantly shorter in Group E than in Group C. The effect-site propofol concentration at loss of consciousness was significantly lower in Group E than in Group C. MBP and HR were significantly lower following propofol induction in both groups, and were significantly increased following intubation in Group C but not in Group E. In conclusion, epidural anaesthesia did not produce profound hypotension following induction of anaesthesia and produced a reduction in the haemodynamic response to tracheal intubation during a target controlled infusion of propofol.     

Induced hypotension with epidural/general anesthesia reduces transfusion in radical prostate surgery

PURPOSE: Radical prostatectomy is associated with substantial blood loss frequently requiring allogeneic blood transfusion. We investigated the efficacy of deliberate hypotension using combined epidural/general anesthesia in reducing allogeneic transfusion requirements in patients undergoing radical prostatectomy. METHODS: In a prospective, randomized, single-blind trial, 102 patients undergoing radical prostatectomy were allocated to either an epidural group (n = 51) or a control group (n = 51). In the epidural group, deliberate hypotension was achieved with a target mean arterial pressure of 55-60 mmHg. The trigger for allogeneic blood transfusion in both groups was a hematocrit value < 0.25. RESULTS: Operative blood loss in the epidural group was significantly less than that in the control group (955 +/- 517 mL vs 1477 +/- 823 mL respectively, P < 0.001). The percentage of patients who reached the threshold trigger for allogenic transfusion was significantly less in the epidural group (8% vs 26%, respectively, P = 0.019) and the number of patients who were actually transfused during hospitalization was also significantly less (P = 0.028). There were no serious adverse events in either group during the study. CONCLUSION: Controlled hypotension using a combined epidural/ general anesthetic technique is associated with significantly less blood loss, and a reduction in the use of allogeneic blood in patients undergoing radical prostatectomy compared to general anesthesia alone.     

Hemodynamic effects of the induction of general anesthesia after low thoracic epidural anesthesia

Sixteen ASA 1 or 2 patients scheduled for abdominal surgery were included in the study after they had given their informed consent. Thirty minutes after starting a low-thoracic epidural anaesthesia (median level of sensitivity loss: T5), the patients were randomly given an intravenous bolus injection of either thiopentone (4 mg.kg-1, n = 8) or etomidate (0.5 mg.-1, n = 8), associated with succinylcholine 1 mg.kg-1. One minute after induction of general anaesthesia, the patients were intubated and mechanically ventilated (V(T) 8 ml.kg-1, rate 12 c.min-1). Mean arterial blood pressure (MAP) (oscillometric method), cardiac output (CO) (transthoracic bioimpedance) and heart rate were recorded semi-continuously. Total peripheral resistances (TPR) were calculated using the formula TPR = (MA/CO)*80. There were no differences between the groups in patient age, height, weight, and cardiovascular consequences of epidural anaesthesia. After anaesthetic induction and before endotracheal intubation, there was a slight decrease in CO in both groups, without any change in MAP. After intubation, MAP increased in both groups through peripheral vasoconstriction, whereas CO did not increase further. A significant tachycardia was occurred only seen in the thiopentone group, before and after tracheal intubation. This study showed that thiopentone and etomidate were suitable drugs for anaesthetic induction in a patient under epidural blockade. However, the absence of tachycardia following etomidate may be beneficial in cardiac patients. The monitoring of cardiac output determinants during thiopentone and etomidate anaesthesia require further invasive investigations.     

Epidural lidocaine with sufentanil and epinephrine for abdominal hysterectomy under general anaesthesia: respiratory depression and postoperative analgesia

The purpose of this investigation was to compare the analgesic actions and side-effects of a 50 micrograms epidural bolus of sufentanil and 50 micrograms epinephrine, with a control group receiving saline and epinephrine. The method employed was a prospective, randomised, double-blind trial involving 40 ASA I or II patients for total abdominal hysterectomy. All received 1.5% lidocaine with 1/200,000 epinephrine epidurally before operation, until a block to T4 was established. Patients were anaesthetised, their tracheas were intubated, and they were allowed to breathe spontaneously before administration of the test drug. Results showed that sufentanil prolonged the duration of local anaesthesia (198 +/- 35 min vs 174 +/- 29 min; P less than 0.05), and of analgesia (288 +/- 85 min vs 188 +/- 42 min; P less than 0.01). There was an increase in somnolence in the sufentanil group (9/20 vs 2/20; P less than 0.05). Glycopyrollate was given to 11/20 patients in the sufentanil group vs 1/20 in the control group (P less than 0.01) following bradycardia and hypotension. Clinical respiratory depression occurred in the sufentanil group; 5/20 patients required controlled ventilation following apnoea greater than 20 sec. It is concluded that epidural sufentanil causes considerable cardiorespiratory depression in the setting of general anaesthesia, and should be used with caution in the spontaneously breathing, anaesthetised patient.     

Effect of epidural versus general anaesthesia on peroperative blood loss during retropubic prostatectomy

Peroperative blood loss, arterial blood pressure and central venous pressure were studied in patients subjected to retropubic prostatectomy. The patients were randomly allocated to two groups, continuous lumbar epidural analgesia for up to 24 hours and a thiopentone-oxyg n-nitrous oxide-alcuronium-pethidine sequence with intermittent positive pressure ventilation. The mean peroperative blood loss during operations under epidural analgesia was significantly less than that under general anaesthesia (370±34 ml vs. 59035 ml, mean SE). Only one patient out of 17 cases of epidural analgesia needed a peroperative blood transfusion, in contrast to 5 out of 21 general anaesthesias. Both the arterial systolic and diastolic pressures, and central venous pressure were significantly lower under epidural analgesia than general anaesthesia. It was concluded that decreased arterial and venous pressure were responsible for the reduced blood loss under epidural analgesia.     

Systemic and pulmonary blood pressure during caesarean section in parturients with gestational hypertension

Twenty severely pre-eclamptic patients requiring caesarean section for delivery were allocated to two groups. One group received epidural anaesthesia consisting of either 20 ml of bupivacaine 0.75 per cent at L3-4 or 12ml at Ll-2. The other group received general anaesthesia consisting of thiopentone, 40 per cent nitrous oxide and halothane 0.5 per cent. Mean arterial pressure (MAP), pulmonary artery pressure (PAP), pulmonary wedge pressure (PWP), and central venous pressure (CVP) were recorded at five-minute intervals for at least 60 minutes before operation and at least every two minutes during anaesthesia. Patients receiving general anaesthesia had pressures recorded every minute during tracheal intubation and extubation. There was a mean increase of MAP of 45 mm Hg, of PAP 20 mm Hg, and PWP 20mm Hg during intubation and extubation. Apart from a slight mean fall in MAP the parturients receiving epidural anaesthesia showed little change in these cardiovascular parameters. It is concluded that tracheal intubation of patients with gestational hypertension produces an increase in MAP, PAP, and PWP which can lead to a significant risk of cerebral haemorrhage and pulmonary oedema. The value and dangers of using short-acting hypotensive agents to prevent these episodes of hypertension has still to be assessed. With epidural anaesthesia there is a danger of hypotension which can be treated with intravenous fluid replacement and ephedrine.     

Remifentanil vs. fentanyl during interventional rigid bronchoscopy under general anaesthesia and spontaneous assisted ventilation.

The treatment of tracheo-bronchial diseases with rigid bronchoscopy requires general anaesthesia without tracheal intubation. Spontaneous assisted ventilation is a safe modality of ventilation. In this study the use of remifentanil and fentanyl is compared during rigid bronchoscopy with spontaneous assisted ventilation. Ninety high-risk patients received fentanyl or remifentanil with propofol for general anaesthesia. During the maintenance fentanyl was delivered at 6.1 +/- 4.6 micrograms kg-1 h-1 and remifentanil at 0.15 +/- 0.07 microgram kg-1 min-1. The same degree of intra-operative respiratory acidosis with similar good operating conditions resulted in both groups. Patients treated with remifentanil recovered more quickly compared with those in the fentanyl group (3.8 +/- 2 vs. 10.4 +/- 9.2 min, P < 0.001). In conclusion, the use of remifentanil during rigid bronchoscopy under general anaesthesia with spontaneous assisted ventilation is safe and assures good operating conditions. Moreover, remifentanil permits a more rapid recovery than fentanyl. The dose of remifentanil is higher than previously described for spontaneously breathing patients.     

Ventilation-Perfusion Relationships During Epidural Analgesia

Resting lung volume (FRC), airway closure (CC) and ventilation-perfusion relationships, using the multiple inert gas elimination technique, were studied during epidural analgesia. The material consisted of 10 patients, 55-84 years of age. Epidural blockade (9-13 ml mepivacaine-adr, 1/200,000) was instituted to an upper level corresponding to Th3-Th6. Minute ventilation and breathing frequency remained unchanged during the epidural block, while cardiac output was significantly increased (4.80-5.74 l/min). The relationship between FRC and CC (FRC-CC) was unchanged during the block, indicating an unchanged magnitude of airway closure. Multiple inert gas elimination data revealed virtually unchanged distribution of ventilation and perfusion during the epidural block in 9 of the 10 patients. It is concluded that lumbar epidural analgesia up to Th3-Th6 does not influence the degree of airway closure, nor does it cause VA/Q mismatching as general anaesthesia does.     

Haemoglobin dilution from epidural-induced hypotension with and without fluid loading

The blood haemoglobin concentration (B-Hb) was measured repeatedly to reflect dilution or concentration changes of the blood during onset of lumbar epidural anaesthesia in 90 elderly men. With crystalloid volume loading (10 ml.kg-1 b.w.), the decrease in B-Hb was twice as great for those who developed hypotension during the onset of the blockade as for patients whose arterial pressure remained normal (P less than 0.001), both when epidural anaesthesia was induced with plain mepivacaine, and when mepivacaine plus adrenaline was used. In a control group where no fluid loading was performed, there was no consistent change in the haemoglobin level, irrespective of blood pressure reaction to the blockade. The results suggest that crystalloid fluid loading allows an increase in blood volume in epidural-induced hypotension.     

Comparison of hypotensive epidural anaesthesia and spinal anaesthesia on blood loss and coagulation during and after total hip arthroplasty

BACKGROUND: Hypotensive epidural anaesthesia (HEA) is a technique for reducing peroperative blood loss by significantly lowering mean arterial pressure (MAP). METHODS: Thirty patients scheduled for primary total hip arthroplasty were given HEA (n=15) or spinal anaesthesia (SPA) (n= 15) with bupivacaine in random order. The dose of bupivacaine was titrated to provide epidural blockade up to T1-T4 and spinal blockade at least to T10. Intravenous adrenaline infusion was adjusted to achieve a MAP of about 50-60 mmHg in the HEA group. During SPA MAP was maintained above 70 mmHg with ephedrine, as needed. RESULTS: Intraoperative blood loss (median and 25th and 75th percentiles) was 400 ml (163-575) in the HEA group and 900 ml (663-1,100) in the SPA group (P<0.05). At 3 h postoperatively cumulative blood loss was still smaller in the HEA group (600 ml versus 1,100 ml, P<0.05). The cumulative number of transfused packed red cell concentrate (PRC) units was smaller in the HEA group than in the SPA group during surgery and postoperatively. Prothrombin time value was smaller in the SPA than in the HEA group (69% versus 79%, P<0.05) at 3 h postoperatively. D-dimer concentrations increased more in the SPA group at the end of the surgery and 3 h postoperatively (P<0.05). CONCLUSIONS: HEA resulted in reduced blood loss due to hypotension and reduced number of transfused PRC units during total hip arthroplasty. Based on lower prothrombin time value and higher D-dimer concentrations in the SPA group, the coagulation system might be better preserved during HEA than SPA.     

Fibre-optic intubation teaching in sedated patients with anticipated difficult intubation

BACKGROUND AND OBJECTIVES: The objective of the study was to assess the safety of training fibre-optic intubation performed under propofol light general anaesthesia in patients with an anticipated difficult intubation. METHODS: Patients with ear, nose and throat cancer having at least two criteria for anticipated difficult intubation and scheduled for fibre-optic intubation were included prospectively. In 26 patients, intubation was performed by an anaesthesia resident (under senior supervision), whereas in 20 patients, it was performed by a senior anaesthesiologist. All patients received propofol light general anaesthesia adjusted to maintain both loss of consciousness and spontaneous ventilation. RESULTS: Of the 46 patients, 45 had successful fibre-optic intubation, and one needed a rescue procedure because of hypoxaemia. Residents failed to intubate four patients, who were easily intubated by the senior. Episodic hypoxaemia (SPO2 < 90%) occurred in three patients in each group. No statistically significant difference was found between junior and senior neither on the duration of the procedure (9.3 +/- 4.9 vs. 7.5 +/- 4.0 min) nor on the propofol consumption (197 +/- 130 vs. 193 +/- 103 mg) or the ETCO2 at the end of the procedure (36 +/- 6 vs. 38 +/- 6 mmHg), respectively. CONCLUSION: Teaching fibre-optic tracheal intubation in patients with anticipated difficult intubation and sedated with propofol did not increase morbidity significantly compared with an experienced anaesthesiologist. Fibre-optic intubation under propofol light general anaesthesia could be safely performed by a resident as long as a senior anaesthesiologist is permanently present, spontaneous ventilation is maintained and a rescue oxygenation technique is immediately available.     

Effect of thoracic epidural anaesthesia on ventilation= perfusion distribution and intrathoracic blood volume before and after induction of general anaesthesia

Background: Gas exchange is impaired during general anaesthesia due to development of shunt and ventilation-perfusion mismatching. Thoracic epidural anaesthesia (TEA) may affect the mechanics of the respiratory system, intrathoracic blood volume and possibly ventilation-perfusion (V_A/Q) distribution during general anaesthesia.
Methods: V_A/Q relationships were analyzed in 24 patients undergoing major abdominal surgery. Intrapulmonary shunt (Qs/ Q_T), perfusion of "low" V_A/Q areas, ventilation of "high V_A/ regions, dead space ventilation and mean distribution of ventilation and perfusion were calculated from the retention/excretion data of six inert gases. Intrathoracic blood volume (ITBV) and pulmonary blood volume (PBV) were determined with a double indicator technique. Recordings were made before and after administration of 8.5±1.5 ml bupivacaine 0.5% (n=12) or 8.3±1.8 ml placebo (n=12) into a thoracic epidural catheter and after induction of general anaesthesia.
Results: Before TEA, QS/QT was normal in the bupivacaine group (222%) and the placebo group (23%). TEA covering the dermatomal segments T 12 to T 4 had no effect on V_A/Q relationships, ITBV and PBV. After induction of general anaesthesia S/T increased to 84% (bupivacaine group, P < 0.05) and to 72% (placebo group, P < 0.05). ITBV and PBV decreased significantly to the same extent in the bupivacaine group and the placebo group.
Conclusions: TEA has no effect on V_A/Q distribution, gas exchange and intrathoracic blood volume in the awake state and does not influence development of S/T and V_A/Q inequality after induction of general anaesthesia.     

BLOOD LOSS DURING MAJOR VAGINAL SURGERY: A Statistical Study of the Influence of General Anaesthesia and Epidural Analgesia

Blood loss was measured using a haemoglobin extraction-dilutiontechnique in 211 patients undergoing major vaginal surgery.Epidural analgesia combined with light general anaesthesia wasused in 102 patients. In 56 instances nitrous oxide and halothanewere used, ventilation being spontaneous, and in 53 patientsnitrous oxide, oxygen and a muscle relaxant were used togetherwith passive pulmonary ventilation. When epidural analgesiawas employed the mean blood loss was about one-third of thatassociated with the other forms of general anaesthesia. It wasnot found necessary to induce profound hypotension with epiduralanalgesia in order to provide satisfactory operating conditions.There was no statistically significant difference in blood losswas less in patients over 65 years than those under 65.     

Rachianesthésie totale après bloc du plexus lombaire par voie postérieure

We report a case of total spinal anaesthesia which occurred after a lumbar plexus block using a posterior approach. After total hip arthroplasty under general anaesthesia, a lumbar plexus block was performed according to Winnie's landmarks at the L4 interspace using a nerve stimulator. Aspiration test for blood and spinal fluid were both negative, as well as a test dose of 3 mL lidocaine 2 %-bupivacaine 0.5 %. One minute after the injection of 27 mL of the same mixture, a complete anaesthetic block occurred with hypotension and loss of consciousness requiring intubation and controlled ventilation during 3h30, without sequelae. Lumbar plexus block using a posterior approach must be performed cautiously and a slow and fractionated injection of the full dose is recommended.