Routine preoperative blood group and save is unnecessary for adult emergency appendicectomies: A retrospective multicentre study

Introduction

Emergency appendicectomy is the most frequently performed emergency general surgical operation in the UK, with around 50,000 appendicectomies carried out each year. ¹ Acute appendicitis commonly affects patients in their second and third decade of life and is more common in males. ² Since laparoscopic appendicectomy was first described in 1983 by Semm, ³ it has become widely accepted as the gold standard treatment for acute appendicitis. ⁴

There are no UK national guidelines, that the authors are aware of, covering the requirement for group and save (ABO, RhD and any unusual red blood cell antibody testing ⁵ ) in the emergency general surgery setting. Current practice within the health board where this study was carried out is that patients must have a valid group and save sample before any laparoscopic procedure is carried out. This is based on the local maximum blood ordering schedule (MBOS). The most recent national guidelines from the National Institute of Health and Care Excellence (NICE) on preoperative investigations date back to 2016, ⁶ cover only elective surgery and do not discuss any requirement for group and save or crossmatching for emergency operations.

Several studies have been published looking at the need for group and save samples to be taken prior to laparoscopic surgery,^7–9 with the outcomes showing the rate of blood transfusion to be low. Fadel et al. published a systematic review in 2022 assessing the requirement for group and save in cholecystectomy and appendicectomy and found that in all 15 studies published, the conclusion was that a group and save was not warranted. ¹⁰

Further to this, three studies have been published in the past three years looking at the need for group and save samples in emergency appendicectomy. Alyacoubi et al. ¹¹ assessed patient records over a two-year period, identifying 451 patients who underwent emergency appendicectomy or diagnostic laparoscopy, and found that only 2 patients required a blood transfusion perioperatively and neither were related to the surgery. Al-Musawi et al. ¹² carried out a similar retrospective study including 1891 patients over a four-year period, finding only one patient who required blood transfusion intraoperatively. However, this study included patients undergoing laparoscopic hernia repairs as well as patients undergoing laparoscopic appendicectomy, and the paper does not comment on which of these procedures the blood transfusion was required for. The final paper published is the only paper the authors are aware of which looks only at the need for group and save in patients undergoing emergency appendicectomy and not including any other procedure. Ibrahim et al. ¹³ included 200 patients in their analysis and found that none of them required perioperative blood transfusion. Despite this growing evidence, many NHS trusts still require a group and save sample to be taken preoperatively for laparoscopic appendicectomy.

The primary aim of this study was to assess the need for blood transfusion in perioperative period in patients undergoing emergency appendicectomy. The secondary aim was to calculate the cost implications of such practice on a routine basis.

Methods and materials

This was a multicentre retrospective cohort study, assessing adult patients who had undergone emergency appendicectomy across four hospitals (two tertiary care hospitals and two district general hospitals) in one NHS trust with a population base of 1.3 million patients. ¹⁴ This was carried out over a 28-month period (August 2018 and November 2020). The inclusion criterion for the study was any patient who had undergone appendicectomy and had haematology and electronic records held by the trust. Exclusion criteria were patients who did not have complete records available, underwent elective appendicectomy, underwent conversion to right hemi-colectomy, were found to have a tumour intraoperatively, or were wrongly coded on electronic records.

Patients eligible for the study were identified via a database held by the histopathology department of all patients whom they had a received an appendix specimen. Data was then recorded for each of these patients and stored in a secure database. Data collected included patient age, sex, American Society of Anesthesiologists (ASA) grade, surgical approach and histopathology findings. From the blood blank database, we recorded if a valid group and save or crossmatch sample was available at the time of surgery, and if a blood transfusion was administered within a 30-day perioperative period.

Institutional Review Board (IRB) approval was not required as this was a retrospective observational study and the study protocols were consistent with the information governance frameworks and recommendations of NHS Scotland, national and international societies and Caldicott requirements. The manuscript was written in line with STROBE guidelines.

Results

A total of 1159 patients met the above inclusion criteria. 54 patients were excluded from the study, leaving 1105 included in the study. Of the 54 patients excluded from the study, 30 were excluded due to incomplete data, 13 due to undergoing right hemi-colectomy, 5 due to being elective patients, 4 due to being found to have a tumour intraoperatively and 2 due to being wrongly coded. The patients had a median age of 37 (IQR 26–52) and 635 (57.5%) of the patients were male (Table 1). 1012 (91.6%) of the patients were ASA 1 or 2 (Table 1).

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Table 1.

Patient's demographics.

Median age (years)	37 years (IQR 26–52)
Gender
Male	635 (57.5%)
Female	470 (42.5%)
ASA grade
ASA 1	518 (46.9%)
ASA 2	494 (44.7%)
ASA 3	71 (6.4%)
ASA 4	8 (0.7%)
Unrecorded ASA	14 (1.3%)

The surgical approach was found to be largely laparoscopic with 890 (80.5%) of all appendicectomies completed laparoscopically. 79 (7.1%) of cases begun laparoscopically and were subsequently converted to an open operation. 119 (10.8%) of the appendicectomies were started as an open right iliac fossa (RIF) incision, while 17 (1.5%) begun as a midline laparotomy (Table 2).

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Table 2.

Surgical approach, histopathology and outcomes.

Surgical approach
Laparoscopic	890 (80.5%)
Laparoscopic converted to open	79 (7.1%)
Open (RIF incision)	119 (10.8%)
Laparotomy	17 (1.5%)
Histopathology
Inflamed	804 (72.8%)
Gangrenous	56 (5.1%)
Perforated	235 (21.3%)
Normal	10 (0.9%)
Total median length of stay (days)	3 days (IQR 2–5)

All appendixes were analysed by histopathology postoperatively with the severity graded as inflamed, gangrenous, perforated or normal. 804 (72.8%) of cases were classed as an inflamed appendix, 56 (5.1%) as gangrenous, 235 (21.3%) as perforated and (10) 0.9% appendixes were histologically normal (Table 2).

Of the 1105 cases identified, 921 preoperative group and saves were taken. 42 (4.6%) patients had one unit of blood crossmatched preoperatively, and 6 (0.7%) patients had two units of blood crossmatched preoperatively. None of the patients in the study required a blood transfusion in the 30-day perioperative period.

Discussion

The results from our retrospective analysis echo with the results from the earlier studies published looking at the need for group and save in emergency appendicectomy, highlighting further that routine preoperative group and save blood sampling is not necessary.^10–13 This study is only the second to look exclusively at emergency appendicectomy and brings further weight to the argument as our study was multicentre, encompassing all four hospitals across one health board, rather than an individual hospital which was noted by the authors of being a limitation of the study by Ibrahim et al. In comparison to Ibrahim et al., our study also increases the number of patients included in the analysis from 200 to 1105. ¹³

Schafer et al. ¹⁶ documented that there is an increase in bleeding risk when inflammatory tissue is present. As far as the authors are aware, this is the only study which has included the pathology of the appendixes in the study. While the study did not primarily assess the risk of bleeding in correlation to the grade of inflammation, our results revealed that 291 (26.3%) of the patients in our study were found to have an appendix classed as either gangrenous or perforated during histopathological analysis and yet none of these patients required a blood transfusion, suggesting that within our cohort, increasing levels of intraabdominal inflammation did not increase the need for blood transfusion. Multiple previous papers have highlighted that the main perceived bleeding risk in laparoscopic surgery is injury to main vessels^17,18 and that this risk is significantly reduced when open entry is used in laparoscopic surgery in comparison to a closed entry technique, with Larobina et al. finding an injury to main vessels in open entry laparoscopic surgery in 0 of 22,465 cases.

As has also been noted in several of the earlier studies,^11–13 we found a significant cost implication to having a valid group and save sample for every patient undergoing emergency appendicectomy. We estimated the cost of all samples processed for our cohort to be £40,164 however this does not consider the time required by laboratory staff and portering staff to carry out the tests, and the equipment needed to collect the blood samples (blood collection tubes, needle, vacuette, tourniquet, alcohol wipes), meaning the true cost is likely to be significantly higher. The total number of appendicectomies carried out annually in the United Kingdom is approximately 50,000. ¹ If each of these patients had one group and save sample taken, at £36 per sample this would incur unnecessary costs of approximately £1.8million, and in many trusts, two group and save samples are required before surgery can begin, ¹⁹ suggesting the true cost is likely to be far higher than this.

A further factor which should be considered when assessing the effects of requiring a group and save before appendicectomy is lost theatre time. It takes a minimum of 30 minutes to process a group and save, ¹² and further time to obtain the sample and transport it to the laboratory. While the scope of this study did not include assessing how long prior to a patient arriving in the theatre group and save samples were taken, it is our experience that frequently patients are found to not have a valid sample and thus delay the operation. Further to this, our study found 136 patients (12% of the cohort) who did not have a valid group and save sample or blood crossmatched, suggesting that there is significant variation in the practice of theatre staff across one health board, further adding to the need for updated national guidelines.

Limitations of this retrospective analysis include patients being excluded from the trial if they underwent conversion to right hemi-colectomy or were found to have a tumour intraoperatively; however, this only accounts for 17 patients in comparison to the 1105 patients who were included.

Data was not recorded assessing patients' individual risk factors for intraoperative bleeding. While we recommend a routine group and save sample is not required for all appendicectomy cases, we strongly recommend that in high-risk patients this should be considered on a case-to-case basis and a group and save sample should be taken if considered appropriate.

Conclusion

The need for perioperative blood transfusion is rare in patients undergoing appendicectomy. It has a significant cost impact as well as causing unnecessary delays if not done promptly. Our study suggests that a routine group and save sampling policy is not necessary for low-risk patients, and we recommend a more selective policy is adopted. Our findings add to current published evidence which demonstrates a need for national guidelines update.