We're unable to sign you in at this time. Please try again in a few minutes.
We were able to sign you in, but your subscription(s) could not be found. Please try again in a few minutes.
There may be a problem with your account. Please contact the AMA Service Center to resolve this issue.
Contact the AMA Service Center:
Telephone: 1 (800) 262-2350 or 1 (312) 670-7827  *   Email: subscriptions@jamanetwork.com
Error Message ......
Original Investigation |

Effect of Relative Decrease in Blood Hemoglobin Concentrations on Postoperative Morbidity in Patients Who Undergo Major Gastrointestinal Surgery

Gaya Spolverato, MD1,2; Yuhree Kim, MD, MPH1,2; Aslam Ejaz, MD, MPH1,2; Steven M. Frank, MD1,2; Timothy M. Pawlik, MD, MPH, PhD1,2
[+] Author Affiliations
1Department of Surgery, Johns Hopkins Hospital, Baltimore, Maryland
2Department of Anesthesiology and Critical Care Medicine, Johns Hopkins Hospital, Baltimore, Maryland
JAMA Surg. 2015;150(10):949-956. doi:10.1001/jamasurg.2015.1704.
Text Size: A A A
Published online

Importance  Delta hemoglobin (ΔHb), defined as the difference between the preoperative hemoglobin (Hb) level and the nadir Hb level during a patient’s hospitalization, may be associated with adverse outcomes even if the absolute level of Hb remains greater than the transfusion threshold of 7 g/dL.

Objective  To evaluate the association between ΔHb and morbidity in patients who undergo major gastrointestinal surgery as an independent factor or combined with the nadir Hb concentration.

Design, Setting, and Participants  Retrospective review of prospectively collected data on patients who underwent pancreatic, hepatic, or colorectal resection from January 1, 2010, through April 30, 2014, at Johns Hopkins Hospital were included in the study. Data regarding the ΔHb concentration following surgery, nadir Hb level, and overall perioperative blood use were obtained and analyzed. Multivariable-adjusted logistic regression models were used to identify the preoperative factors associated with ΔHb and the effect of ΔHb on perioperative morbidity. The study and data analysis took place from January 22 through February 20, 2015.

Interventions  Major gastrointestinal surgery and packed red blood cell transfusion.

Main Outcomes and Measures  Overall morbidity and ischemic-specific complications.

Results  Of the 4669 patients who underwent major gastrointestinal surgery, the median ΔHb level after surgery was 40%. Patients with multiple comorbidities (American Society of Anesthesiologists Physical Status score of 3-4: odds ratio [OR], 1.96; 95% CI, 1.30-2.97; P <.001; ≥3 coexisting medical conditions: OR, 1.62; 95% CI, 1.08-2.42; P = .001) and those who underwent pancreatic surgery (OR, 1.98; 95% CI, 1.18-3.33; P = .01) were at increased risk of having a ΔHb of 50% or greater. Compared with patients who had a ΔHb level of less than 50% and a nadir Hb level of 7 g/dL or greater, patients with a ΔHb level of 50% or greater whose nadir Hb level was less than 7 g/dL were at a high risk of developing postoperative complications (OR, 6.60; 95% CI, 4.34-10.03; P < .001); in particular, a ΔHb level of 50% or greater was strongly correlated with a risk of ischemic complications, even if the nadir Hb level was 7 g/dL or greater (OR, 5.68; 95% CI, 1.44-22.39; P = .01).

Conclusions and Relevance  A ΔHb level of 50% or greater following gastrointestinal surgery was associated with complications, especially ischemic adverse events, even if the nadir Hb level remained at 7 g/dL or greater.

Figures in this Article


Place holder to copy figure label and caption
Figure 1.
Incidence of Complications Stratified by Different Combinations of ΔHb and Nadir Hb Levels

Of the patients with a hemoglobin (Hb) level of 7 g/dL or greater (to convert to grams per liter, multiply by 10.0), those with a delta hemoglobin (ΔHb) level of 50% or greater were at higher risk of complications (P < .001).

Graphic Jump Location
Place holder to copy figure label and caption
Figure 2.
Spline Function Plot of the Relationship Between Decrease in Hemoglobin Level and Morbidity

A, Relationship stratified by sex. B, Relationship stratified by type of surgery.

Graphic Jump Location




Also Meets CME requirements for:
Browse CME for all U.S. States
Accreditation Information
The American Medical Association is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians. The AMA designates this journal-based CME activity for a maximum of 1 AMA PRA Category 1 CreditTM per course. Physicians should claim only the credit commensurate with the extent of their participation in the activity. Physicians who complete the CME course and score at least 80% correct on the quiz are eligible for AMA PRA Category 1 CreditTM.
Note: You must get at least of the answers correct to pass this quiz.
Please click the checkbox indicating that you have read the full article in order to submit your answers.
Your answers have been saved for later.
You have not filled in all the answers to complete this quiz
The following questions were not answered:
Sorry, you have unsuccessfully completed this CME quiz with a score of
The following questions were not answered correctly:
Commitment to Change (optional):
Indicate what change(s) you will implement in your practice, if any, based on this CME course.
Your quiz results:
The filled radio buttons indicate your responses. The preferred responses are highlighted
For CME Course: A Proposed Model for Initial Assessment and Management of Acute Heart Failure Syndromes
Indicate what changes(s) you will implement in your practice, if any, based on this CME course.


Some tools below are only available to our subscribers or users with an online account.

2 Citations

Sign in

Purchase Options

• Buy this article
• Subscribe to the journal
• Rent this article ?

Related Content

Customize your page view by dragging & repositioning the boxes below.

See Also...
Articles Related By Topic
Related Collections