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Meta-Analysis
. 2013 Jul 31;2013(7):CD006798.
doi: 10.1002/14651858.CD006798.pub4.

Day-surgery versus overnight stay surgery for laparoscopic cholecystectomy

Jessica Vaughan  1 , Kurinchi Selvan Gurusamy, Brian R Davidson
Affiliations
Meta-Analysis

Day-surgery versus overnight stay surgery for laparoscopic cholecystectomy

Jessica Vaughan et al. Cochrane Database Syst Rev. .

Abstract

Background: Laparoscopic cholecystectomy is used to manage symptomatic gallstones. There is considerable controversy regarding whether it should be done as day-surgery or as an overnight stay surgery with regards to patient safety.

Objectives: To assess the impact of day-surgery versus overnight stay laparoscopic cholecystectomy on patient-oriented outcomes such as mortality, severe adverse events, and quality of life.

Search methods: We searched the Cochrane Hepato-Biliary Group Controlled Trials Register and the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library, MEDLINE, EMBASE, Science Citation Index Expanded, and mRCT until September 2012.

Selection criteria: We included randomised clinical trials comparing day-surgery versus overnight stay surgery for laparoscopic cholecystectomy, irrespective of language or publication status.

Data collection and analysis: Two authors independently assessed trials for inclusion and independently extracted the data. We analysed the data with both the fixed-effect and the random-effects models using Review Manager 5 analysis. We calculated the risk ratio (RR), mean difference (MD), or standardised mean difference (SMD) with 95% confidence intervals (CI) based on intention-to-treat or available case analysis.

Main results: We identified a total of six trials at high risk of bias involving 492 participants undergoing day-case laparoscopic cholecystectomy (n = 239) versus overnight stay laparoscopic cholecystectomy (n = 253) for symptomatic gallstones. The number of participants in each trial ranged from 28 to 150. The proportion of women in the trials varied between 74% and 84%. The mean or median age in the trials varied between 40 and 47 years.With regards to primary outcomes, only one trial reported short-term mortality. However, the trial stated that there were no deaths in either of the groups. We inferred from the other outcomes that there was no short-term mortality in the remaining trials. Long-term mortality was not reported in any of the trials. There was no significant difference in the rate of serious adverse events between the two groups (4 trials; 391 participants; 7/191 (weighted rate 1.6%) in the day-surgery group versus 1/200 (0.5%) in the overnight stay surgery group; rate ratio 3.24; 95% CI 0.74 to 14.09). There was no significant difference in quality of life between the two groups (4 trials; 333 participants; SMD -0.11; 95% CI -0.33 to 0.10).There was no significant difference between the two groups regarding the secondary outcomes of our review: pain (3 trials; 175 participants; MD 0.02 cm visual analogue scale score; 95% CI -0.69 to 0.73); time to return to activity (2 trials, 217 participants; MD -0.55 days; 95% CI -2.18 to 1.08); and return to work (1 trial, 74 participants; MD -2.00 days; 95% CI -10.34 to 6.34). No significant difference was seen in hospital readmission rate (5 trials; 464 participants; 6/225 (weighted rate 0.5%) in the day-surgery group versus 5/239 (2.1%) in the overnight stay surgery group (rate ratio 1.25; 95% CI 0.43 to 3.63) or in the proportion of people requiring hospital readmissions (3 trials; 290 participants; 5/136 (weighted proportion 3.5%) in the day-surgery group versus 5/154 (3.2%) in the overnight stay surgery group; RR 1.09; 95% CI 0.33 to 3.60). No significant difference was seen in the proportion of failed discharge (failure to be discharged as planned) between the two groups (5 trials; 419 participants; 42/205 (weighted proportion 19.3%) in the day-surgery group versus 43/214 (20.1%) in the overnight stay surgery group; RR 0.96; 95% CI 0.65 to 1.41). For all outcomes except pain, the accrued information was far less than the diversity-adjusted required information size to exclude random errors.

Authors' conclusions: Day-surgery appears just as safe as overnight stay surgery in laparoscopic cholecystectomy. Day-surgery does not seem to result in improvement in any patient-oriented outcomes such as return to normal activity or earlier return to work. The randomised clinical trials backing these statements are weakened by risks of systematic errors (bias) and risks of random errors (play of chance). More randomised clinical trials are needed to assess the impact of day-surgery laparoscopic cholecystectomy on the quality of life as well as other outcomes of patients.

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Conflict of interest statement

None known.

Figures

1
1
Prisma Flow Chart
2
2
Methodological quality graph: review authors' judgments about each methodological quality item presented as percentages across all included studies.
3
3
Methodological quality summary: review authors' judgments about each methodological quality item for each included study.
4
4
Trial sequential analysis of mortality 
 The diversity‐adjusted required information size (DARIS) was calculated to 352,564 patients, based on the proportion of patients in the control group with the outcome of 0.2%, a relative risk reduction of 20%, an alpha of 5%, a beta of 20%, and a diversity of 0%. To account for zero event groups, a continuity correction of 0.01 was used in the calculation of the cumulative Z‐curve (blue line). After accruing a total of 492 patients in six trials, only 0.14% of the DARIS has been reached. Accordingly, the trial sequential analysis program does not show the required information size and the trial sequential monitoring boundaries. As shown, the conventional boundaries have also not been crossed by the cumulative Z‐curve.
5
5
Trial sequential analysis of pain 
 Trial sequential analysis of pain showing that the cumulative Z‐curve (blue line) enters the futility area after the third trial. The diversity‐adjusted required information size (DARIS) was 359 participants based on a minimal relevant difference (MIRD) of 1 cm on the visual analogue scale, a variance (VAR) of 11.41, an alpha (a) of 5%, a beta (b) of 20%, and a diversity (D2) of 0%. The results are compatible with lack of difference in pain scores between day‐surgery and overnight stay surgery for laparoscopic cholecystectomy.
6
6
Trial sequential analysis of time to return to activity 
 The diversity‐adjusted required information size (DARIS) was 2,354 participants based on a minimal relevant difference (MIRD) of 1 day, a variance (VAR) of 74.96, an alpha (a) of 5%, a beta (b) of 20%, and a diversity (D2) of 0%. After accruing 217 participants in two trials, only 9.2% of the DARIS has been reached. Accordingly, the trial sequential analysis program does not show the futility area. Neither the trial sequential boundaries nor the conventional statistical boundaries for benefits or harms of day‐surgery versus overnight stay were crossed by the cumulative Z‐curve (blue line).
7
7
Trial sequential analysis of proportion of participants requiring hospital readmission 
 The diversity‐adjusted required information size (DARIS) was calculated to 21,030 participants, based on the proportion of participants in the control group with the outcome of 3.24%, a relative risk reduction of 20%, an alpha of 5%, a beta of 20%, and a diversity of 0%. To account for zero event groups, a continuity correction of 0.01 was used in the calculation of the cumulative Z‐curve (blue line). After accruing 290 participants in three trials, only 1.38% of the DARIS has been reached. Accordingly, the trial sequential analysis program does not show the required information size and the trial sequential monitoring boundaries. As shown, the conventional boundaries have also not been crossed.
8
8
Trial sequential analysis of proportion of participants with failed discharge 
 The diversity‐adjusted required information size (DARIS) was calculated to 15,968 participants, based on the proportion of participants in the control group with the outcome of 20.09%, a relative risk reduction of 20%, an alpha of 5%, a beta of 20%, and a diversity of 81.98%. To account for zero event groups, a continuity correction of 0.01 was used in the calculation of the cumulative Z‐curve (blue line). After accruing 419 participants in the five trials, only 2.62% of the DARIS has been reached. Accordingly, the trial sequential analysis program does not show the required information size and the trial sequential monitoring boundaries. As shown, the conventional statistical boundaries have also not been crossed at the end of five trials although the cumulative Z‐curve crossed temporarily the conventional statistical boundary favouring overnight stay after two trials. Such a finding is likely to be a random error.
1.1
1.1. Analysis
Comparison 1 Day case versus overnight stay for laparoscopic cholecystectomy, Outcome 1 Serious adverse events.
1.2
1.2. Analysis
Comparison 1 Day case versus overnight stay for laparoscopic cholecystectomy, Outcome 2 Quality of life.
1.3
1.3. Analysis
Comparison 1 Day case versus overnight stay for laparoscopic cholecystectomy, Outcome 3 Pain (cm visual analogue scale score).
1.4
1.4. Analysis
Comparison 1 Day case versus overnight stay for laparoscopic cholecystectomy, Outcome 4 Time to return to activity (days).
1.5
1.5. Analysis
Comparison 1 Day case versus overnight stay for laparoscopic cholecystectomy, Outcome 5 Time to return to work (days).
1.6
1.6. Analysis
Comparison 1 Day case versus overnight stay for laparoscopic cholecystectomy, Outcome 6 Number of hospital readmissions.
1.7
1.7. Analysis
Comparison 1 Day case versus overnight stay for laparoscopic cholecystectomy, Outcome 7 Number of people requiring hospital readmission.
1.8
1.8. Analysis
Comparison 1 Day case versus overnight stay for laparoscopic cholecystectomy, Outcome 8 Failed discharge.
2.1
2.1. Analysis
Comparison 2 Sensitivity analysis, Outcome 1 Quality of life (imputed data removed).
2.2
2.2. Analysis
Comparison 2 Sensitivity analysis, Outcome 2 Pain (imputed data removed).
2.3
2.3. Analysis
Comparison 2 Sensitivity analysis, Outcome 3 Time to return to activity (imputed data removed).
2.4
2.4. Analysis
Comparison 2 Sensitivity analysis, Outcome 4 Number of hospital readmissions (imputed data removed).
2.5
2.5. Analysis
Comparison 2 Sensitivity analysis, Outcome 5 Number of people requiring hospital readmission (best‐best).
2.6
2.6. Analysis
Comparison 2 Sensitivity analysis, Outcome 6 Number of people requiring hospital readmission (worst‐worst).
2.7
2.7. Analysis
Comparison 2 Sensitivity analysis, Outcome 7 Number of people requiring hospital readmission (worst‐best).
2.8
2.8. Analysis
Comparison 2 Sensitivity analysis, Outcome 8 Number of people requiring hospital readmission (best‐worst).
2.9
2.9. Analysis
Comparison 2 Sensitivity analysis, Outcome 9 Failed discharge (best‐best).
2.10
2.10. Analysis
Comparison 2 Sensitivity analysis, Outcome 10 Failed discharge (worst‐worst).
2.11
2.11. Analysis
Comparison 2 Sensitivity analysis, Outcome 11 Failed discharge (best‐worst).
2.12
2.12. Analysis
Comparison 2 Sensitivity analysis, Outcome 12 Failed discharge (worst‐best).
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Update of

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