|Year : 2013 | Volume
| Issue : 2 | Page : 65-71
Laparoscopic cholecystectomy under spinal anaesthesia: A prospective, randomised study
Sangeeta Tiwari1, Ashutosh Chauhan1, Pallab Chaterjee1, Mohammed T Alam2
1 Department of Surgery, Military Hospital, Agra, Uttar Pradesh, India
2 Department of Anaesthesia, Military Hospital, Agra, Uttar Pradesh, India
|Date of Submission||02-Dec-2011|
|Date of Acceptance||05-Apr-2012|
|Date of Web Publication||22-Apr-2013|
36/3 Nehru Enclave, Lucknow Cantt, Lucknow, Uttar Pradesh
Source of Support: None, Conflict of Interest: None
Context: Spinal anaesthesia has been reported as an alternative to general anaesthesia for performing laparoscopic cholecystectomy (LC). Aims: Study aimed to evaluate efficacy, safety and cost benefit of conducting laparoscopic cholecystectomy under spinal anaesthesia (SA) in comparison to general anaesthesia(GA) Settings and Design: A prospective, randomised study conducted over a two year period at an urban, non teaching hospital. Materials and Methods: Patients meeting inclusion criteria e randomised into two groups .Group A and Group B received general and spinal anaesthesia by standardised techniques. Both groups underwent standard four port laparoscopic cholecystectomy. Mean anaesthesia time, pneumoperitoneum time and surgery time defined primary outcome measures. Intraoperative events and post operative pain score were secondary outcome measure. Statistical Analysis Used: The Student t test, Pearson's chi-square test and Fisher exact test. Results: Out of 235 cases enrolled in the study, 114 cases in Group A and 110 in Group B analysed. Mean anaesthesia time appeared to be more in the GA group (49.45 vs. 40.64, P = 0.02) while pneumoperitoneum time and corresponding the total surgery time was slightly longer in the SA group. 27/117 cases who received SA experienced intraoperative events, four significant enough to convert to GA. No postoperative complications noted in either group. Pain relief significantly more in SA group in immediate post operative period (06 and 12 hours) but same as GA group at time of discharge (24 hours). No late postoperative complication or readmission noted in either group. Conclusion: Laparoscopic cholecystectomy done under spinal anaesthesia as a routine anaesthesia of choice is feasible and safe. Spinal anaesthesia can be recommended to be the anaesthesia technique of choice for conducting laparoscopic cholecystectomy in hospital setups in developing countries where cost factor is a major factor.
Keywords: General anaesthesia, laparoscopic cholecystectomy, spinal anaesthesia
|How to cite this article:|
Tiwari S, Chauhan A, Chaterjee P, Alam MT. Laparoscopic cholecystectomy under spinal anaesthesia: A prospective, randomised study. J Min Access Surg 2013;9:65-71
|How to cite this URL:|
Tiwari S, Chauhan A, Chaterjee P, Alam MT. Laparoscopic cholecystectomy under spinal anaesthesia: A prospective, randomised study. J Min Access Surg [serial online] 2013 [cited 2021 Jun 21];9:65-71. Available from: https://www.journalofmas.com/text.asp?2013/9/2/65/110965
| ¤ Introduction|| |
Endotracheal general anaesthesia (GA) is the anaesthetic technique of choice for laparoscopic cholecystectomy (LC). Regional anaesthesia too (spinal/epidural/combined spinal epidural) has been reported as a sole technique for performing LC as an alternative to GA for LC. Initially it was reported only for cases who were otherwise high risk candidates for general anaesthesia, , more recently it has been reported as a routine technique for otherwise healthy patients also. , It was thought that laparoscopy cholecystectomy necessitates endotracheal intubation. This was to prevent aspiration, abdominal discomfort and hypercarbia which was expected secondary to induction of CO 2 pneumoperitoneum.  Recent studies demonstrate that laparoscopic cholecystectomy with low-pressure CO 2 pneumoperitoneum can indeed be safely performed under spinal anaesthesia (SA)  In spite of the emerging evidence that laparoscopic cholecystectomy can be performed safely under regional anaesthesia, it has not gained widespread acceptance. We designed a randomised controlled study to assess if spinal anaesthesia, instead of general anaesthesia, can be used as a routine in clinical practice.
| ¤ Materials and Methods|| |
This prospective, randomised study was conducted at an urban, secondary level hospital in a period of 2 years from January 2009 to December 2010.
Consecutive newly diagnosed cases of cholelithiasis who reported to the Department for surgery and who met the following criteria were enrolled in the study:
Exclusion criteria were as follows:
- American Society of Anaesthesiologist's (ASA) physical status I, II or III
- Age between 18 and 80 years of age.
There was no cut off criteria for body mass index (BMI) per se as an exclusion criterion. Similarly, history of previous open upper abdominal surgery too was not taken as strict criteria for exclusion.
- Acute Inflammatory process (cholecystitis, pancreatitis or cholangitis)
- Suspected/confirmed common bile duct stones
- Anxiety prone patient/diagnosed psychological morbidity
- Bleeding diasthesis
- Local spinal deformity which precluded safe spinal anaesthesia
- Cases of chronic obstructive pulmonary disease
Permission from Institutional ethical committee was sought for and obtained. All patients were explained about the study and written informed consent obtained. All patients were interviewed by the anaesthesiologist in a pre-operative visit who in turn specifically instructed them about possible intraoperative events while under SA, like vomiting, shoulder pain and anxiety. It was instructed to them that in eventuality of ibid events occurring, intravenous medications would be administered and, if required, conversion to GA would be done. As there would be multiple outcomes possible, no separate analysis was undertaken to determine the size of the study groups.
Patients were randomised to undergo spinal anaesthesia or general anaesthesia for the cholecystectomy by a random number generator. The individual resident responsible for randomisation was not subsequently involved in the surgery or in the post operative follow-up. The surgery was performed by the same set of consultant surgeons and anaesthesiologists for patients in both the study groups. The post-operative monitoring and data collection was done by an independent observer who had not been involved in either pre-operative or intraoperative course of events.
Pre-anaesthetic medication was standardised for all patients. Each patient received Fentanyl 50 mg IV, Ranitidine 50 mg IV and Ondasterone 4 mg IV. Pre-anaesthetic values of heart rate, mean arterial pressure, respiratory rate, and pulse oximetry were recorded.
In the general anaesthesia group, anaesthesia was induced with 2.5 mg/kg of propofol and 0.6 mg/kg -1 of rocuronium. Maintenance of anaesthesia was done with O 2 , N 2 O and sevoflurane. The respiratory rate was adjusted to maintain P ET CO 2 between 32 and 36 mmHg. Expired concentrations of CO 2 , O 2 , and sevoflurane were monitored continuously by a gas analyzer. Residual neuromuscular blockade was antagonized with 2.5 mg of neostigmine and 0.4 mg of glycopyrollate at the end of the surgery.
In the spinal anaesthesia group, the patients were placed in sitting or left lateral decubitus position as deemed comfortable. The subarachnoid space puncture was performed between the L 3 -L 4 apophyses and 2.5-3.5 ml of hyperbaric 0.5% bupivacaine were injected. Afterwards, patients were placed in the supine position with a head-down position. After the surgeon confirmed anaesthesia at T4 level by pin prick, "go-ahead" was given. If the mean arterial pressure dropped below 60 mmHg, 3 μg of mephenataramine was administered. During the procedure, anxiety was treated by 2 mg midazolam and pain with fentanyl 50 μg in intravenous boluses.
Laparoscopic cholecystectomy was performed according to the standard four-port standard technique.  Certain salient features of the technique practised for both the groups, GA as well as SA, were as follows:
The following criteria were established for conversion of the anaesthesia from SA to GA:
- After the second trocar, the subdiaphragmatic surface of the liver was bathed with 30 ml of a solution which contained 10 ml each of 2% Lignocaine and 0.5% Bupivacaine dissolved in 10 ml of saline.
- The pneumoperitoneum was maintained with CO2 at 8-10 mmHg.
- Nasogastric tube was not introduced routinely. It was done if the surgeon desired decompression of stomach.
- After gall bladder had been extracted, the gall bladder fossa liver was bathed with 20 ml of solution with 5 ml each of 2% Lignocaine and 0.5% Bupivacaine dissolved in 10 ml of saline.
- Patient anxiety.
- Pain which was not relieved by addition of Inj Fentanyl 50 μg /kg.
- Bleeding which could not be controlled by routine manoeuvres.
Continuous monitoring of hemodynamic parameters was maintained for all patients in both the groups with non invasive multiparameter monitor
Following parameters were also noted in all cases in both the groups:
- Anaesthesia time: It was defined as time taken from spinal puncture to final dressing of patient in SA group while it was the time taken from induction to extubation for the GA group.
- Surgery time: This was defined as time from first incision to final suture in both the groups.
- Pneumoperitoneum time: This was defined as time from CO 2 insuffulation through veress needle till expulsion of all CO 2 at end of the procedure.
- Intraoperative significant events were defined as pain in the right shoulder, anxiety, headache, nausea, vomiting, and abdominal discomfort.
Patient was shifted to general ward after surgery and maintained on IV fluids for 4 hours post-surgery. Pain relief was maintained by Tab Tramadol 50 mg 08 hourly. InjPentazocin 30 mg was supplemented as a second rescue analgesia if patient persisted to have pain. Thereafter, operating surgeon along with anaesthesiologist evaluated the patient for pain, nausea, and vomiting, consciousness level and vital parameters (including oxygen saturation). Post-operative pain was evaluated, in both groups, by the Visual Analogue Scale  at 6, 12 and 24 hours after the end of the surgery. Other post-operative events related to the surgery or anaesthesia, such as discomfort, nausea, vomiting, shoulder pain, urinary retention, headache, or any other neurologic complaint, were also recorded. Patients were routinely discharged to home the next day, unless some complication warranted further stay. Mean anaesthesia time, pneumoperitoneum time and surgery time defined primary outcome measures. Intraoperative events and post operative pain score were secondary outcome measure.
The Student's t-test was used to compare means and percentages by the Pearson's chi-square test or Fisher exact test. Differences were considered significant when P< 0.05.
| ¤ Results|| |
During the study period, 277 cases of cholelithiasis reported to the Surgery outpatient department (OPD). Out of these 42 cases were deemed ineligible to be enrolled in the study [Table 1]. Two hundred thirty-five cases were enrolled in the study and the progress of the study is summarised in [Figure 1]. One hundred fourteen cases in the GA group and 110 cases in the SA group were finally available for per protocol analyses. These groups were evenly matched as per age and gender distribution [Table 2]. [Table 3] summarises the mean anaesthesia, pneumoperitoneum and total surgery time in both the groups. Mean anaesthesia time appeared to be more in the GA group (49.45 vs. 40.64, P = 0.02). It must be noted that that this was the anaesthesia time in the operating theatre and did not include persistence of anaesthesia in post-operative room for the SA group. Though the pneumoperitoneum time and corresponding the total surgery time was slightly longer in the SA group, it was not statistically significant.
SA Group Among the 117 cases who were randomised to receive SA, the level of anaesthesia was adequate in all to commence laparoscopic surgery. However, as the surgery proceeded, there were 27 cases of intraoperative events which required some intervention on anaesthesiologist's part [Table 4]. Out of these, 4 were significant enough for the patients to be intubated and changed into GA. These included 02 cases of discomfort abdomen, one case of anxiety and one case of nausea/vomiting. The other 23 could be managed with protocol outlined earlier and permitted entire surgery to be completed under SA. Three cases had to be converted to open cholecystectomy. In two cases there were dense adhesions in calot's and in one there was haemorrhage. These cases too were converted to GA. Therefore out of initial 117 cases randomised to receive SA, seven (5.9%) had to be converted to GA.
Post-operative events were noticed in 11/110 cases (10%) [Table 5]. Patients with urinary retention were catheterised. The two cases of hypotension were treated with saline infusion only. No additional medication was required. Three cases developed typical post dural puncture headache which subsided with Injection Pentazocin 30 mg IM. Two cases complained pain at site of lumbar puncture. These were treated with Injection Tramadol (50 mg) IM. All patients were discharged the next day. They were followed up in OPD till sutures were removed 7-10 days later. There were no late post-operative complications noted.
GA Group. Among the 118 cases that were randomised to receive GA, successful laparoscopic surgery was accomplished in 114 cases. Four cases had to be converted to open cholecystectomy because in two cases there was haemorrhage, one had a CBD injury and one had dense adhesions in calots triangle. Post operative events were noticed in 24/114 cases (21%) [Table 5]. Commonest complaint noticed was pain abdomen (12/114, 10.5%). All patients received Inj Pentazocin 30 mg IM in addition to the standard Inj Tramadol. The cases of nausea/vomiting received additional Inj Ondasteron 8 mg IV. [Table 6] summarises the visual analogue score for pain measured in both the groups at 06, 12 and 24 hours after completion of surgery. The pain was less in SA group in immediate operative period (up to 12 hours) but was similar to the other group at time of discharge (24 hours), Similar to the SA group, all patients were discharged the next day. There were no late post-operative complications or readmissions noted in either group.
| ¤ Discussion|| |
Though regional anaesthesia for laparoscopic cholecystectomy has been shown to be safe, and associated with better post operative pain control, it has not become the anaesthesia procedure of choice. There may be multiple reasons for this. It is assumed that pneumoperitoneum induces rise in intra-abdominal pressure. This may result in regurgitation of gastric content thus necessitating the use of endotracheal intubation to prevent aspiration in such an eventuality. , The increased intra-abdominal pressure during pneumoperitoneum, together with the head-up tilt used in upper abdominal laparoscopies, is believed to decrease venous return to the heart. , Spinal anaesthesia itself induces peripheral vasodilatation. Hence, there is a fear that laparoscopic procedure done under spinal anaesthesia may result in hypotension. Indeed, effects of CO 2 pneumoperitoneum on intra-operative haemodynamics under SA is not a well studied scenario. In our study, we notice that liberal pre-anaesthetic hydration prevents occurrence of hypotension. Sinha et al.  noted an incidence of hypotension as 20.5% in their series. While we did have hypotension in three cases (5/114, 4.3%), it could be corrected with saline infusion and selective alpha blocker agent (Inj Mephenataramine). We did have one case whose nausea and vomiting was severe enough to warrant immediate intubation. The negative effects of the pneumoperitoneum with CO 2 on the respiratory function have been widely investigated. Initially, absorption of CO 2 increases its elimination in the expired air, in the arterial and venous blood. , This carboxemia induces metabolic and respiratory acidosis which decreases arterial and mixed venous pH and arterial pO 2 . , In our series we noticed that the SpO 2 remained within normal limits for the patients undergoing LC under SA. Retention of CO 2 and hypoxemia were not observed in the spinal anaesthesia group during the procedure. This experience is similar to that noted by other series , and confirms safety of creating CO 2 pneumoperitoneum under SA. Overall, four out the 114 cases (3.6%) of LC under SA were converted to GA. This is similar to experience of other authors too where the incidence of conversion from SA to GA was noted to range from nil to 2.8%. ,,
Incidence of referred pain to the right shoulder, while doing LC under regional anaesthesia, has been described as ranging from 25%-43%. ,,, Referred pain to right shoulder is a well described phenomena and is thought to occur due to irritation of subdiaphgramatic surface by the CO 2 pneumoperitoneum.  The incidence of the same in our series was 8/114 cases (7%). All of these were managed by Intravenous fentanyl and none required conversion to GA. We attribute this low incidence of referred shoulder pain to liberal use of local anaesthetic agents (Lignocaine plus Bupivacaine) to bathe the subdiaphgramatic surface immediately after creating pneumoperitoneum. This is also helped by the fact we used low pressure pneumoperitoneum (<10 mmHg) during the surgical procedure. While standard LC entails a pneumoperitoneum at 12-16 mmHg, pneumoperitoneum pressure below 10 mmHg has been shown to be associated with lesser abdominal/shoulder pain. 
Low pressure pneumoperitoneum in our cases added to technical complexity of the dissection process. The surgeon had to be slower and gentler in tissue dissection. Additionally, on occasions, it became necessary to interrupt the procedure when the patient complained of discomfort and then the anaesthesiologist had to intervene with additional medication. This explains the fact that the pneumoperitoneum time and correspondingly the surgery time was more in the SA group. Other studies , too have documented the technical difficulty faced by the surgeon when operating in limited field permitted by low pressure pneumoperitoneum. The significant advantage of this is in terms of reduced post-operative pain, less use of analgesics, preservation of pulmonary function, and reduced hospital stay.
The post-operative recovery of patients was normal in all patients of both the groups. It is described that SA is associated with lower frequency of serious peri-operative morbidities and an improved outcome when compared to GA. , In our series the incidence of post-operative events which required intervention was 21% in GA group compared to 11% in the SA group. But in our opinion, it is not justified to compare the two groups on this basis. While in one group the events were peculiar to GA, in the other they were peculiar to SA. Perhaps the only event which would be common to both would be surgical procedure related pain which was consistently reported significantly less by the patients who had undergone the surgery under SA as compared to those who had undergone it under GA. We believe this was due to the sensory blockade which persists for some time in the post-operative period. The patients in SA group seemed to have lesser pain in immediate post-operative period but by the time of discharge the level of post-operative pain/discomfort was same for both groups. Bessa et al.,  in a similar study, too confirm that LC done under SA results in significantly less early post-operative pain, compared to that performed under general anaesthesia.
It may be argued that GA permits true "day care" anaesthesia with the patient being discharged to home the same evening while SA would entail an overnight stay. Based on own experience, we would agree that GA would permit "day care LC" even in healthcare setups of developing countries.  But it is imperative to understand that true day care anaesthesia on an universal basis is less likely to be feasible in a developing country like ours where there are inherent limitation of availability of reliable transport, facility for home nursing, and the fact that majority of the cases reporting to our urban hospitals do so from far off rural areas. Hence, most patients have to be admitted at least for an overnight period whether they are done under GA or SA.
Though the surgery done under spinal anaesthesia was technically more demanding and resulted in longer operating time, there were no late complications noted in our series which would allay the fear that technical difficulty in surgery would result in compromise in patient safety. However, it would be pertinent to mention that this endeavour should be undertaken by surgeons with adequate skills and experience in laparoscopic surgery.
A valid criticism to the present study may emanate from the fact that no pre-study power analysis or sample size calculation was done. Hence, as has been pointed out earlier  in respect to similar studies like the present one, it may not be feasible to draw correct conclusions. This remains a limitation to studies like this because they take into account multiple outcomes measures of varied type. It may not be possible to confirm correctness of sample size calculation or provide the power and level of significance for each test with a singular sample size. Nevertheless, the present study provides a large sample size based on which a larger, more focused studies can be designed.
This study confirms the feasibility and safety of spinal anaesthesia as the sole anaesthesia technique for conduct of elective laparoscopic cholecystectomy (LC). The patient outcomes are similar to that observed if the surgery is done under general anaesthesia. This study did not include a cost analysis, but other studies  indicate that laparoscopic cholecystectomy under SA is more cost effective than under GA. This makes SA an attractive option as the anaesthesia of choice especially in developing countries.
| ¤ Conclusion|| |
Laparoscopic cholecystectomy done under spinal anaesthesia as a routine anaesthesia of choice is feasible and safe. Spinal anaesthesia can be recommended to be the anaesthesia technique of choice for conducting laparoscopic cholecystectomy in hospital setups in developing countries where cost factor is a major factor.
| ¤ References|| |
|1.||Pursnani KG, Bazza Y, Calleja M, Mughal MM. Laparoscopic cholecystectomy under epidural anaesthesia in patients with chronic respiratory disease. Surg Endosc 1998;12:1082-4. |
|2.||Gramatica L Jr, Brasesco OE, Luna MA, Martinessi V, Panebianco G, Labaque F, et al. Laparoscopic cholecystectomy performed under regional anaesthesia in patients with obstructive pulmonary disease. Surg Endosc 2002;16:472-5. |
|3.||Tzovaras G, Fafoulakis F, Pratsas K, Georgopoulou S, Stamatiou G, Hatzitheofilou C. Laparoscopic cholecystectomy under spinal anaesthesia: A pilot study. Surg Endosc 2006;20:580-2. |
|4.||Sinha R, Gurwara AK, Gupta SC. Laparoscopic cholecystectomy under spinal anaesthesia: A study of 3492 patients. J Laparoendosc Adv Surg Tech A 2009;19:323-7. |
|5.||Sharp JR, Pierson WP, Brady CE. Comparison of CO2 and N2O-induced discomfort during peritoneoscopy under local anaesthesia. Gastroenterology 1982;82:453-6. |
|6.||Gautam B. Spinal anaesthesia for laparoscopic cholecystectomy: A feasibility and safety study. Kathmandu Univ Med J (KUMJ) 2009;7:360-8. |
|7.||Feiteha MS, Curet MJ. Laparoscopic cholecystectomy. In: Zucker KA, editor.Surgical Laparocopy. Lippincott Williams & Wilkins; 2001.p.122-7. |
|8.||Price DD, McGrath PA,Rafii A, Buckingham B. The validation of visual analogue scales as ratio scale measures for chronic and experimental pain. Pain 1983;17:45-56. |
|9.||Gutt CN, Oniu T, Mehrabi A, Schemmer P, Kashfi A, Kraus T,et al. Circulatory and respiratory complications of carbon dioxide insufflation. Dig Surg 2004;21:95-105. |
|10.||Hirvonen EA, Poikolainen EO, Pääkkönen ME, Nuutinen LS. The adverse hemodynamic effects of anesthesia, head-up tilt, and carbon dioxide pneumoperitoneum during laparoscopic cholecystectomy. Surg Endosc 2004;14:272-7. |
|11.||Ali Y, Elmasry MN, Negmi H, Al Ouffi H, Fahad B, Rahman SA. The feasibility of spinal anesthesia with sedation for laparoscopic general abdominal procedures in moderate risk patients. Middle East J Anesthesiol 2008;19:1027-39. |
|12.||Imbelloni LE, Fornasari M, Fialho JC, Sant'Anna R, Cordeiro JA. General anesthesia versus spinal anesthesia for laparoscopic cholecystectomy. Rev Bras Anestesiol 2010;60:217-27. |
|13.||Gebhardt H, Bautz A, Ross M, Loose D, Wulf H, Schaube H. Pathophysiological and clinical aspects of the CO2 pneumoperitoneum (CO2-PP). Surg Endosc 1997;11:864-7. |
|14.||Gándara V, de Vega DS, Escriú N, Zorrilla IG. Acid-base balance alterations in laparoscopic cholecystectomy. Surg Endosc 1997;11:707-10. |
|15.||van Zundert AA, Stultiens G, Jakimowicz JJ, Peek D, van der Ham WG, Korsten HH, et al. Laparoscopic cholecystectomy under segmental thoracic spinal anaesthesia: A feasibility study. Br J Anaesth 2007;98:682-6. |
|16.||Sarli L, Costi R, Sansebastiano G,Trivelli M, Roncoroni L. Prospective randomized trial of low-pressure pneumoperitoneum for reduction of shoulder-tip pain following laparoscopy. Br J Surg 2000;87:1161-5. |
|17.||Gurusamy KS, Samraj K, Davidson BR. Low pressure versus standard pressure pneumoperitoneum in laparoscopic cholecystectomy. Cochrane Database Syst Rev 2009;15:CD006930. |
|18.||Chok KS, Yuen WK, Lau H, Fan ST. Prospective randomized trial on low-pressure versus standard-pressure pneumoperitoneum in outpatient laparoscopic cholecystectomy. Surg Laparosc Endosc Percutan Tech 2006;16:383-6. |
|19.||Joshipura VP, Haribhakti SP, Patel NR, Naik RP, Soni HN, Patel B, et al. A prospective randomized, controlled study comparing low pressure versus high pressure pneumoperitoneum during laparoscopic cholecystectomy.Surg Laparosc Endosc Percutan Tech 2009;19:234-40. |
|20.||Standl T, Eckert S, Schulteam Esch J. Postoperative complaints after spinal and thiopentone-isofluraneanesthesia in patients undergoing orthopaedic surgery. Spinal versus general anaesthesia. Acta Anaesthesiol Scand 1996;40:222-6. |
|21.||Rodgers A, Walker N, Schug S, McKee A, Kehlet H, van Zundert A, et al. Reduction of postoperative morbidity and mortality with epidural or spinal anesthesia: Results from overview of randomized trials. BMJ 2000;321:1493. |
|22.||Bessa SS, El-Sayes IA, El-Saiedi MK, Abdel-Baki NA, Abdel-Maksoud MM. Laparoscopic cholecystectomy under spinal versus general anesthesia: A prospective, randomized study. J Laparoendosc Adv Surg Tech A 2010;20:515-20. |
|23.||Chauhan A, Mehrotra M, Bhatia PK, Baj B, Gupta AK. Daycare laparoscopic cholecystectomy: A feasibility study in a public health service hospital in a developing country. World J Surg 2006;30:1-6. |
|24.||Sun P, Jia Y.Comments on "Laparoscopic cholecystectomy under spinal versus general anesthesia: A prospective, randomized study"-can you really have the conclusion? J Laparoendosc Adv Surg Tech A 2011;21:259. |
|25.||Liu X, Wei C, Wang Z, Wang H. Different anesthesia methods for laparoscopic cholecystectomy. Anaesthesist 2011;60:723-8. |
[Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6]