OBJECTIVE The purpose of this study was to classify elements of patients' discomfort in the resuscitation room after open or laparoscopic abdominal surgery as per health care professionals' perceptions. METHODS A prospective cross-sectional study at a tertiary hospital in Spain. METHODS Resuscitation room nurses administered the Postoperative Discomfort Inventory to physicians and nurses with >1 year experience working closely with patients who had undergone abdominal surgery, asking them to score nine items related to patients' discomfort in the first 8 hours after surgery on an 11-point scale (0 = absent to 10 = very severe). Interobserver agreement among proxy reporters was measured with the Spearman's ρ; correlations >0.35 was considered adequate agreement. RESULTS Of 125 eligible professionals, 116 (93%) participated (63 [54%] nurses and 53 [46%] physicians; mean age, 38 ± 12 years; 86 [74%] women). Professionals' perception of discomfort differed significantly between patients undergoing open surgery and those undergoing laparoscopic surgery; after open surgery, the most common types were pain (7.1 ± 1.8), movement restriction (7 ± 1.75), and dry mouth (6.6 ± 2.6), whereas after laparoscopic surgery, the most common types were dry mouth (5.85 ± 2.8), abdominal bloating (5.3 ± 2.5), and pain (5 ± 2.2). The Spearman's ρ correlations were inadequate for all items except for dry mouth in open surgery (r = 0.40). CONCLUSIONS Pain, movement restriction, abdominal bloating, and dry mouth were the main causes of discomfort. Our findings highlight the need to be vigilant for all manifestations of discomfort after abdominal surgery to enable timely treatment.