†These authors contributed equally.
The purpose of this study was to determine which patient- or surgery-related
factors are predictive of need for perioperative transfusion to avoid obtaining
unnecessary pre-operative type and screens (T&S). We conducted an observational
retrospective cohort study of 1200 women
Every year in the United States (US), over 100,000 new gynecological cancers are diagnosed [1]. Operative management is a mainstay of treatment for many of these cancers [2]. One significant surgical risk is blood loss given not only the inherent nature of surgery, but also the vascular nature of tumors of the female reproductive tract [3]. Gynecologic cancer surgeries require treatment with blood products in as many as 13.8% of cases, and transfusion is associated with increased risk of perioperative morbidity and mortality in this population [4].
Preoperative laboratory testing accounts for approximately
Although women undergoing gynecologic oncology surgery are considered at relatively high risk for perioperative hemorrhage, the actual proportion of women requiring transfusion represents a small minority [4]. Consequently, many of these women receive preoperative testing that is not only costly, but also does not substantially impact their care. However, it remains unclear which women undergoing gynecologic surgery will require transfusion and thus may benefit from the preoperative T&S, which is currently the standard of care at our institution.
We conducted a retrospective cohort study using a convenience sample of 1200 women undergoing surgery on a gynecologic oncology service at our academic institution from 2009-2016. This study was exempt by our institution’s Institutional Review Board (IRB; protocol # IRB2019-00629). Our institution’s IRB does not require informed consent for retrospective, de-identified data. Therefore, consent was not obtained in accordance with institutional guidelines.
Data collected included patient demographics, type of procedure
(major, defined as entering the peritoneal cavity, versus minor, defined as no
violation of the peritoneal cavity [7]), route of procedure (open, laparoscopic,
vaginal, other (e.g. vulvar)), and indication for procedure (cancer versus
possible cancer versus benign). Inclusion criteria included women aged
Of note, at our institution, preoperative T&S is not mandated.
Transfusion at our institution is performed based on clinician judgement and
patient clinical status, without strict transfusion criteria. Hematocrit was
analyzed as a categorical variable (
We used univariate analysis including: T-tests, chi-square tests,
Fisher’s exact tests, and ANOVA for initial analysis based on the continuous or
categorical nature of each independent variable to compare each designated factor
with the outcome of transfusion status. Factors that had a significant
association with transfusion in univariate analysis were identified and then
subjected to a regression model. We utilized a log-binomial regression analysis
to examine the outcome of transfusion (vs. no transfusion) with predictive
variables of age, indication, surgery type, Hct level (
We performed all analyses in SAS 9.4 (SAS Institute Inc., Cary,
NC). We used relative risk (RR) in lieu of odds ratio (OR) because our
transfusion rate was under 10% and the primary outcome was transfusion versus no
transfusion [9]. We defined statistical significance as P
Overall, 900 (75.0%) of women underwent preoperative T&S. Of these 900, 701
(77.9%) did not undergo further blood testing (i.e. conversion to T&C) or
transfusion, 118 (13.1%) were converted to a T&C, and 80 (8.9%) ultimately
underwent transfusion. Of the 300 patients who did not undergo T&S, none
received intraoperative or postoperative T&S, T&C, or transfusion. Transfusions
were evenly split between two of the three surgeons who together provided 98.5%
of the data (with the remaining 1.5% of the data coming from the third surgeon,
none of whose patients received a transfusion). Patient demographics and
transfusion outcome are shown in Table 1. Of the 1200 women, 1033 (87.5%)
identified as white/Caucasian, 78 (6.6%) as black/African American, 19 (1.6%)
as Asian, and 51 (4.3%) as other. The mean age was 55.5 (
Overall (n = 1200) | Not transfused (n = 701) | Converted to T & C but not transfused (n = 118) | Transfused (n = 80) | P-Value* | |||||
Characteristic | No. | % | No. | % | No. | % | No. | % | |
Age | |||||||||
Mean | 55.5 | 55.6 | 58.8 | 58.1 | |||||
St. Dev | 14.9 | 13.6 | 12.9 | 12.9 | 0.025 | ||||
BMI | |||||||||
Mean | 30.2 | 30.0 | 30.8 | 31.1 | |||||
St. Dev | 9.2 | 9.3 | 7.8 | 10.4 | 0.433 | ||||
Race | |||||||||
White | 1033 | 87.5 | 614 | 88.9 | 97 | 82.9 | 72 | 90.0 | |
Asian | 19 | 1.6 | 9 | 5.6 | 2 | 7.7 | 0 | 7.5 | |
Black | 78 | 6.6 | 39 | 1.3 | 9 | 1.7 | 6 | 0.0 | |
Other | 51 | 4.3 | 29 | 4.2 | 9 | 7.7 | 0 | 2.5 | 0.407 |
Ethnicity | |||||||||
Hispanic | 88 | 9.0 | 53 | 9.2 | 10 | 9.1 | 3 | 4.6 | |
Not Hispanic | 890 | 91.0 | 521 | 90.8 | 100 | 90.9 | 63 | 95.5 | 0.442 |
Abbreviations: T&S, Type and Screen; T&C, Type and Cross. *P-Value compares outcomes of Transfusion Status: Transfused vs. Not Transfused. Age: t-test; BMI: Wilcoxon-Mann-Whitney test; Race: Fisher’s exact test; Ethnicitiy: Fisher’s exact test. |
Not Transfused (n = 1111) | Transfused (n = 81) | P-Value* | |||
Characteristic | No. | % | No. | % | |
Age | |||||
Mean | 55.3 | 58.2 | |||
St. Dev | 15.1 | 13.1 | 0.085 | ||
BMI | |||||
Mean | 30.1 | 31.3 | |||
St. Dev | 9.1 | 10.4 | 0.266 | ||
Race | |||||
White | 954 | 87.4 | 73 | 90.1 | |
Asian | 71 | 6.5 | 6 | 7.4 | |
Black | 19 | 1.7 | 0 | 0.0 | |
Other | 47 | 4.3 | 2 | 2.5 | 0.700 |
Ethnicity | |||||
Hispanic | 84 | 9.3 | 3 | 4.5 | |
Not Hispanic | 822 | 90.7 | 64 | 95.5 | 0.265 |
*P-Value compares outcomes of Transfusion Status: Transfused vs. Not Transfused. One-way ANOVAs. |
Not Transfused (n = 1111) | Transfused (n = 81) | P-Value* | |||
Comorbidity | No. | % | No. | % | |
Hypertension | 386 | 34.7 | 30 | 37.0 | 0.676 |
Hyperlipidemia | 186 | 16.7 | 10 | 12.4 | 0.303 |
Obesity | 435 | 39.2 | 32 | 39.5 | 0.950 |
Diabetes | 132 | 11.9 | 12 | 14.8 | 0.434 |
Hyperthyroidism | 12 | 1.08 | 0 | 0.0 | 1.000 |
Hypothyroidism | 107 | 9.6 | 15 | 18.5 | 0.011 |
COPD | 40 | 3.6 | 4 | 4.9 | 0.535 |
Asthma | 111 | 10.0 | 6 | 7.4 | 0.451 |
OSA | 41 | 3.7 | 1 | 1.2 | 0.357 |
GERD | 126 | 11.3 | 7 | 8.6 | 0.456 |
Diverticulosis | 26 | 2.3 | 3 | 3.7 | 0.441 |
Kidney Stones | 22 | 2.0 | 2 | 2.5 | 0.676 |
ETOH Use | 553 | 51.2 | 36 | 45.0 | 0.284 |
Abbreviations: OSA, Obstructive Sleep Apnea; GERD, Gastroesophageal Reflux Disease; COPD, Chronic Obstructive Pulmonary Disease; ETOH, Alcohol. *P-Value compares outcomes of Transfusion Status: Transfused vs. Not Transfused. Hypertension, Hyperlipidemia, Obesity, Diabetes: Chi-square test; Hyperthyroidism, COPD, Asthma, Sleep apnea, Diverticulosis, Kidney stones: Fisher’s exact test; Hypothyroidism, GERD: Chi square test. |
In terms of preoperative surgical indications, 681 (57.2%) had a
diagnosed or suspected cancer, and 508 (42.7%) had a benign condition (Table 4).
Of all surgeries, 678 (57.1%) were major (entering a major body cavity, in this
case the peritoneal cavity [7]) while 510 (42.9%) were minor (no violation of
the peritoneal cavity). Four hundred sixty-eight (39.3%) were performed via an
open (laparotomy) approach, 113 (9.5%) were performed via laparoscopic approach,
566 (47.6%) were performed vaginally (e.g. hysteroscopy, dilation and
curettage), and 43 (3.6%) were classified as other (e.g. vulvar surgery). Surgical indication was significantly predictive of need for transfusion
(P = 0.002). Patients undergoing major surgery were significantly more
likely to need transfusion as compared to those undergoing minor surgery
(P
Not Transfused (n = 1111) | Transfused (n = 81) | P-Value* | |||
Characteristic | No. | % | No. | % | |
Indication | |||||
Cancer/Possible Cancer | 621 | 56.1 | 60 | 74.1 | |
Benign | 487 | 44.0 | 21 | 25.9 | 0.002 |
Surgery | |||||
Major | 607 | 54.8 | 71 | 87.6 | |
Minor | 500 | 45.2 | 10 | 12.4 | |
Surgery Route | |||||
Open | 409 | 36.9 | 59 | 72.8 | |
Laparoscopic | 109 | 9.8 | 4 | 4.9 | |
Vaginal | 550 | 49.6 | 16 | 19.8 | |
Other | 41 | 3.7 | 2 | 4.5 | |
Hct | |||||
240 | 25.86 | 40 | 55.56 | ||
688 | 74.14 | 32 | 44.44 | ||
*P-Value compares outcomes of Transfusion Status: Transfused vs. Not Transfused. One-way ANOVAs. |
Not Transfused (n = 1111) | Transfused (n = 81) | P-Value* | |||
Grade | No. | % | No. | % | |
0 | 688 | 74.1 | 32 | 44.4 | |
1 | 196 | 21.1 | 21 | 29.2 | |
2 | 38 | 4.1 | 18 | 25 | |
3 | 6 | 0.65 | 1 | 1.4 | |
*P-Value compares outcomes of Transfusion Status: Transfused vs. Not Transfused. Grades: 0 signifies Hct Hct between 24 and 30%, and 3 signifies Hct |
Finally, we wondered whether various patient- or surgery-related
factors would be independently predictive of need for transfusion, controlling
for other patient- or surgery-related factors (Table 6). When controlling for
patient age, indication, and Hct levels, major surgery, relative to minor
surgery, was associated with a 3.625-fold increased risk of transfusion
(P = 0.003). Moreover, Hct levels
Characteristic | Relative Risk | 95% Confidence Interval | P-Value |
Age (Continuous) | 1.002 | (0.986, 1.017) | 0.829 |
Indication (CA or Possible CA vs. Benign) | 0.991 | (0.594, 1.653) | 0.972 |
Surgery (Major vs. Minor) | 3.625 | (1.556, 8.444) | 0.003 |
Hct ( |
3.357 | (2.137, 5.274) | |
Route (MIS vs. Open) | 0.612 | (0.3289, 1.1388) | 0.121 |
Abbreviations: CA, Cancer; Hct, Hematocrit. |
Not Transfused (n = 1109) | Transfused (n = 81) | P-Value* | |||
Route | No. | % | No. | % | |
Minimally invasive | 700 | 96.95 | 22 | 3.05 | |
Open | 409 | 87.39 | 59 | 12.61 | |
Total* | 1109 | 93.19 | 81 | 6.81 | |
*Missing data points = 10. Chi-square test. |
In our cost-conscious healthcare climate, we seek to decrease expenditures while maintaining high value care. A notable recent example is the introduction of enhanced recovery after surgery (ERAS) protocols, which aim to reduce hospital lengths of stay and associated costs while optimizing recovery and return to normal life after surgery [10, 11].
With respect to preoperative testing, a single T&S costs between
Globally, the volume of surgery has been estimated to be on the order of ~234 million major surgical procedures per year, with surgical procedures accounting for a relatively greater proportion of healthcare dollars spent per capita in high- and middle-expenditure countries versus low expenditure countries [14]. There have been international efforts to map out and eliminate cost-inefficient care in the perioperative setting, including for patients undergoing gynecologic surgery, which have demonstrated substantial unnecessary costs including inappropriate screening tests [15, 16]. Still, much of this work has investigated bundled care costs without pinpointing individual tests which may be superfluous, and little has been conducted specifically within the gynecologic oncology setting.
Here, we were motivated to determine which factors may predict need
for transfusion, with the goal of eliminating unnecessary pre-operative T&S
testing. This is a relevant issue in the gynecologic oncology setting in which up
to 14% of patients require perioperative transfusion, as compared to 1-2% of
patients undergoing surgery on a benign gynecology service [4, 17]. We found an
overall transfusion rate of 6.7%. Patients who were older, who underwent more
invasive operations, including hysterectomy, and who underwent surgery for a
known cancer or possible cancer were more likely to need transfusion and may
benefit from a pre-operative T&S. While we initially stratified our outcomes
according to type and screen alone versus conversion to type and cross versus
transfusion (Table 1), we believed that the most relevant outcome transfusion
versus no transfusion, thus in subsequent analyses we used this binary outcome.
Interestingly, we found that of the patient comorbidities examined,
hypothyroidism was associated with need for transfusion (Table 3), which may be
related to decreased factor VIII activity and prolonged partial thromboplastin
time in this population [18]. By contrast, factors such as patients’ BMI and
other comorbidities were not predictive of need for transfusion. Controlling for
other surgery- and patient-related factors, major surgery was the only
significant risk factor for need for transfusion. These findings will help
clinicians decide whether to order a pre-operative T&S prior to gynecologic
surgery. If these findings are adopted widely in appropriate patients, cost
savings would be substantial. For instance, in the current study, of all the
patients who received T&S, 487/508 patients with benign indications were not
transfused, 500/510 patients undergoing minor surgery were not transfused, and
688/710 patients with preoperative Hct of greater than or equal to 36% were not
transfused. By a conservative estimate, our institution spent
Several limitations of the present work must be discussed. Firstly, we conducted a retrospective study at a single institution. Future work should examine the question of which patients require pre-operative T&S in a prospective nature, ideally among a large group of patients in multiple, varied institutions. Secondly, in our cohort, a minority of patients requiring major surgery underwent surgery via a minimally invasive approach (laparoscopy, robotic) due to surgeon preferences at our institution during the timeframe captured. On the other hand, our preoperative testing policy is standardized across the institution and is not based on individual surgeon’s preferences. With the increasing use of minimally-invasive approaches in gynecologic oncology [19], future studies should determine whether transfusion requirements vary in a larger group of patients undergoing surgery via minimally invasive versus laparotomy approaches. It has been noted that patients undergoing robotic and laparoscopic surgery for complex operations such as cytoreduction for ovarian cancer or radical hysterectomy for cervical cancer can undergo successful surgery with low blood loss and minimal risk of transfusion [20, 21, 22]. Given the increasing use of minimally invasive surgery in the gynecologic oncology setting, it will be important to assess need for preoperative type and screen in this group of patients, which is likely lower than that of patients undergoing open procedures. Nevertheless, the open approach remains common, especially in low resource settings and across the developing world. Thus, our findings could be particularly applicable to these populations where cost savings is of great concern.
While we chose to examine a host of patient-related and surgery-related factors that could have influenced need for transfusion, other factors not directly addressed in this study might also predict likelihood for perioperative transfusion in the gynecologic oncology setting. For instance, molecular markers such as BRCA mutation status in ovarian cancer patients can be used to risk stratify patients and prognosticate various clinical endpoints including surgical procedure performed, operative time, estimated blood loss, and hospital length of stay [23, 24]. Other factors that we did not specifically examine in this study but which may be associated with risk of transfusion include perioperative neoadjuvant chemotherapy, preoperative anemia, and preoperative transfusion. WHO performance status and Cherlson Comorbidity Index are also important to consider in evaluating which patients may not tolerate significant blood loss and who are also at increased risk for perioperative transfusion. Future work should seek to incorporate these additional factors into risk models for perioperative transfusion in the gynecologic oncology setting.
Finally, it is important to bear in mind in interpreting our findings that 509 of the 900 patients (56.6%) who underwent T&S had benign findings on final pathology (Table 3). Hence, the majority of patients undergoing surgery on the gynecologic oncology service in this study interval were not cancer patients, although these rates are fairly typical [25].
In summary, we have shown that women undergoing surgery on a gynecologic oncology service are more likely to require transfusion if they had cancer, required a major operation, or had a lower Hct at baseline. Based on these findings, we feel it is reasonable for providers to consider forgoing routine T&S in patients who are known to have a benign condition, are undergoing a minor operation, and have normal preoperative hematocrit levels. It should be noted, however, that surgical factors such as route/approach may be more of a function of individual surgeon preference/skill, and thus future work should seek to determine whether specific diagnoses or procedures performed by laparotomy versus laparoscopy versus vaginal approach are associated with greater or lesser need for perioperative transfusion.
MP conceived of the study. SD, GK and SB-C collected the data and analyzed the results. GK and MP wrote the initial manuscript draft. All authors edited the draft and approved the final version.
We thank Elizabeth Roemer and the Department of Obstetrics, Gynecology & Reproductive Medicine at Stony Brook Medicine for support for this work. GWK received funding from the National Institutes of Health (NIH) award 1F30MH110103 for medical and graduate school training.
The authors have no conflicts of interest to report. The authors have no relevant financial disclosures to report. Data from this work were presented at the 2019 ACOG Annual Clinical and Scientific Meeting in Nashville, TN.