K. Mealy

BACKGROUND: Surgical site infection (SSI) is an infection occurring in an incisional wound within 30 days of surgery and significantly effects patient recovery and hospital resources. OBJECTIVE: This study sought to determine the relationship between preoperative serum albumin and SSI. METHODS: A study of 524 patients who underwent gastrointestinal surgery in 4 institutions was performed. Patients were identified using a prospective SSI database and hospital records. Serum albumin was determined preoperatively in all patients. Hypoalbuminemia was defined as albumin <30 mg/dL. Data are presented as median (interquartile range) and a difference between groups was examined using Mann-Whitney U and Fisher exact test and multiple logistic regression analysis. RESULTS: A total of 105 patients developed a SSI (20%). The median time to the development of SSI was 7 (5-10) days. Having an emergency procedure (P = 0.003), having a procedure over 3 hours in duration (P = 0.047), being American Society of Anaesthetics grade 3 (P = 0.03) and not receiving preoperative antibiotics (P = 0.007) were associated with SSI while having a laparoscopic procedure reduced the likelihood of SSI (P = 0.004). Patients who developed a SSI had a lower preoperative serum albumin (30 [25-34.5] vs. 36 [32-39], P < 0.001). On multivariate analysis, hypoalbuminemia was an independent risk factor for SSI development (relative risk, RR = 5.68, 95% confidence interval: 3.45-9.35, P < 0.001). Albumin <30 mg/dL was associated with an increased rate of deep versus superficial SSI (P = 0.002). The duration of inpatient stay was negatively correlated with preoperative albumin (R = -0.319, P < 0.001). CONCLUSIONS: Hypoalbuminemia is an independent risk factor for the development of SSI following gastrointestinal surgery and is associated with deeper SSI and prolonged inpatient stay.

Acute whiplash injuries are a common cause of soft tissue trauma for which the standard treatment is rest and initial immobilisation with a soft cervical collar. Because the efficacy of this treatment is unknown a randomised study in 61 patients was carried out comparing the standard treatment with an alternative regimen of early active mobilisation. Results showed that eight weeks after the accident the degree of improvement seen in the actively treated group compared with the group given standard treatment was significantly greater for both cervical movement (p less than 0.05) and intensity of pain (p less than 0.0125).

To determine whether mechanical bowel preparation influences the incidence of anastomotic dehiscence following colorectal surgery, 186 patients undergoing elective left colonic or rectal resection were randomized before surgery to bowel preparation (n = 89) or no bowel preparation (n = 97). Surgical technique was standardized and no patient had a defunctioning colostomy. Seventeen patients were excluded (seven with preparation, ten without). Indications for surgery in the remaining 169 patients were carcinoma (133 patients), diverticular disease (26), inflammatory bowel disease (six) and miscellaneous conditions (four). Operations performed were left colonic resection or reversal of Hartmann's procedure (26 with preparation, 28 without) and anterior resection (56 versus 59). The overall morbidity rate (18 per cent) was similar in the two groups. All seven clinical anastomotic leaks occurred after low anterior resection, in three of the 39 patients who had undergone bowel preparation and four of the 36 who had not (P > 0.9). Two deaths occurred, both of patients who had received bowel preparation, one being secondary to anastomotic leakage. Bowel preparation does not influence outcome after elective colorectal surgery.

The proinflammatory cytokines play a central role in mediating cellular and physiological responses, and levels may reflect immune system effectiveness. In this study, the effect of ageing on the inflammatory response was examined using a novel method to detect production of the proinflammatory cytokines, i.e. tumour necrosis factor-alpha (TNF-alpha), IL-6 and IL-1beta. Peripheral blood mononuclear cells (PBMC) obtained from healthy donors of different ages were incubated for 0, 24, 48 and 72 h with or without phorbol 12-myristate 13-acetate (PMA) stimulation. At each time point these cells were permeabilized and incubated with secondary conjugated FITC MoAbs specific for each cytokine. A flow cytometric system was developed to quantify specific intracellular fluorescence in T cells (CD3+) and monocytes (CD14+). TNF-alpha, IL-6 and IL-1beta production in cell culture supernatants was also measured using ELISAs. In older subjects, flow cytometry detected significant increases in intracellular T cell TNF-alpha and IL-6 (P < 0.05). IL-1beta was not detected in any of the T cell samples. Likewise, the monocytes of older subjects demonstrated increased intracellular levels of all three cytokines, but these increases were not significant (P > 0.05). These changes in intracellular proinflammatory cytokine levels may explain some of the exaggerated inflammatory responses seen in elderly patients.

We thank Mr Moran for his interest in our study and found his observations stimulating.He points out that the damage may not have arisen solely from reperfusion and that some change may have occurred while the muscle was ischaemic.The fact that the histological appearance of the muscle in the group 1 patients was initially normal and that there was a delay of around 24 h between the operation and the release of creatine kinase indicates that the damage evolves slowly.We believe that there are changes occurring in muscle kept ischaemic