How to Avoid Nontherapeutic Laparotomy in Patients With Multiple Organ Failure of Unknown Origin. The Role of CT Scan Revisited

Diagnosis of intra-abdominal diseases in critically ill patients remains a clinical challenge. Physical examination is unreliable whereas exploratory laparotomy may aggravate patient''s condition and delay further evaluation. Only a few studies have investigated the place of computed tomography (CT) on this hazardous situation. We aimed to evaluate the ability of CT to prevent unnecessary laparotomy during the management of critically ill patients. Charts of all consecutive patients who had undergone an emergency nontherapeutic laparotomy from 1996 to 2013 were retrospectively studied and patient''s demographic, clinical characteristics, and surgical findings were collected. During this period 59 patients had an unnecessary laparotomy. Fifty-one patients had at least one preoperative imaging and 36 had a CT scan. CT scans were interpreted to be normal (n = 12), with minor anomalies (n = 10), or major anomalies (pneumoperitoneum, portal venous gas/pneumatosis intestinalis, thickened gallbladder wall, and small bowel obstruction signs). Surgical exploration was performed through laparotomy (n = 55) or laparoscopy. Overall mortality was 37% with a median survival after surgery of 7 days. In univariate analysis, hospitalization in ICU before surgical exploration was the only factor related to death. In our series CT scans, objectively interpreted, helped avoid unnecessary surgical exploration in 61% of our patients.Key words: Laparotomy, Critical care, Abnormalities, Digestive system, CT scansEarly diagnosis of acute nontraumatic life-threatening intra-abdominal diseases remains a clinical challenge. In critically ill patients, pathologies such as mesenteric ischemia, intestinal perforation, pancreatitis and biliary diseases carry a high mortality rate ranging from 50% to 100%.^1,2 For these patients, physical examination can be unreliable due to deep sedation and absence of acute abdomen symptoms, and use of imaging studies may therefore be necessary to identify intra-abdominal pathologies and prevent delay in diagnosis. Also, imaging studies may help avoiding unnecessary laparotomy which can be associated with a morbidity rate up to 22%.³ Ultrasonography (US) can be performed at the bedside and is a good alternative for the diagnosis of biliary tract disease; however, it is highly operator dependent, made difficult by abdominal distension,⁴ and not effective for bowel perforation or ischemia.⁵ Computed tomography (CT) scans are increasingly used for emergency patients with acute nontraumatic abdominal pain and tenderness, however, misinterpretation or overinterpretation of CT findings are not rare.^6,7 Despite the large use of imaging procedures in the evaluation of intra-abdominal pathologies, few studies have attempted to assess their impact on the management of critically ill patients.^8,9 The aim of this observational work was to evaluate the results of preoperative imaging procedures, especially CT, in a consecutive series of nontraumatic critically ill patients who underwent nontherapeutic surgical abdominal exploration in a French university tertiary care hospital.     

Brain function rescue effect of lactate following hypoglycaemia is not an adaptation process in both normal and Type I diabetic subjects

Aims/hypothesis. We have previously shown that lactate protects brain function during insulin-induced hypoglycaemia. An adaptation process could, however, not be excluded because the blood lactate increase preceded hypoglycaemia.¶Methods. We studied seven healthy volunteers and seven patients with Type I (insulin-dependent) diabetes mellitus with a hyperinsulinaemic (1.5 mU · kg^–1· min^–1) stepwise hypoglycaemic clamp (4.8 to 3.6, 3.0 and 2.8 mmo/l) with and without Na-lactate infusion (30 μmol · kg^–1· min^–1) given after initiation of hypoglycaemic symptoms.¶Results. The glucose threshold for epinephrine response was similar (control subjects 3.2 ± 0.1 vs 3.2 ± 0.1, diabetic patients = 3.5 ± 0.1 vs 3.5 ± 0.1 mmol/l) in both studies. The magnitude of the response was, however, blunted by lactate infusion (AUC; control subjects 65 ± 28 vs 314 ± 55 nmol/l/180 min, zenith = 2.6 ± 0.5 vs 4.8 ± 0.7 nmol/l, p < 0.05; diabetic patients = 102 ± 14 vs 205 ± 40 nmol/l/180 min, zenith = 1.4 ± 0.4 vs 3.2 ± 0.3 nmol/l, p < 0.01). The glucose threshold for symptoms was also similar (C = autonomic 3.0 ± 0.1 vs 3.0 ± 0.1, neuroglycopenic = 2.8 ± 0.1 vs 2.9 ± 0.1 mmol/l, D = autonomic 3.2 ± 0.1 vs 3.2 ± 0.1, neuroglycopenic 3.1 ± 0.1 vs 3.2 ± 0.1 mmol/l) but peak responses were significantly attenuated by lactate (score at 160 min C = 2.6 ± 1 vs 8.8 ± 1, and 0.4 ± 0.4 vs 4.8 ± 1, respectively; p = 0.02–0.01, D = 1.3 ± 0.5 vs 6.3 ± 1.7, and 2.3 ± 0.6 vs 5.7 ± 1.1 p = 0.07–0.02). Cognitive function deteriorated in both studies at similar glucose thresholds (C = 3.1 ± 0.1 vs 3.0 ± 0.1, D = 3.2 ± 0.1 vs 3.3 ± 0.2 mmol/l). Although in normal subjects a much smaller impairment was observed with lactate infusion (Δ four-choice reaction time at 160 min = 22 ± 12 vs 77 ± 31 ms; p = 0.02), in Type I diabetic patients lactate infusion was associated with an improvement in cognitive dysfunction (0.2 ± 0.4 vs –38 ± 0.2 Δ ms, p = 0.0001).¶Conclusion/interpretation. A blood lactate increase after the development of hypoglycaemic symptoms reduces counterregulatory and symptomatic responses to insulin-induced hypoglycaemia and favours brain function rescue both in normal and diabetic subjects. These findings confirm that lactate is an alternative substrate to glucose for cerebral metabolism under hypoglycaemic conditions. [Diabetologia (2000) 43: 733–741]     

Increased presence of anti-HLA antibodies early after allogeneic granulocyte colony-stimulating factor-mobilized peripheral blood hematopoietic stem cell transplantation compared with bone marrow transplantation

We have recently shown that the use of allogeneic granulocyte colony-stimulating factor (G-CSF)-mobilized peripheral blood hematopoietic stem cell transplantation (PBHSCT), as compared with bone marrow transplantation (BMT), is associated with increased titers of antibodies (Abs) directed against red blood cell ABO antigens. To further evaluate the influence of a G-CSF-mobilized PBHSCT graft on alloimmune Ab responses, we examined the frequency of anti-HLA Abs after transplantation in the setting of the same randomized study, comparing PBHSCT with BMT in adults. Anti-HLA Ab presence was determined by complement-dependent cytotoxicity assay (CDC) and flow cytometry in the recipient before and 30 days after transplantation as well as in the donor before graft donation. The use of PBHSCT was significantly associated with increased detection of anti-HLA immunoglobulin G (IgG) Abs early after transplantation as evidenced by flow cytometry (11 of 24 versus 4 of 27 transplant recipients, P =.03) and, less so, by CDC (5 of 24 versus 1 of 27 transplant recipients, P =.09). The difference between PBHSCT and BMT was further heightened when analysis was restricted to anti-HLA IgG Ab-negative donor/recipient pairs. In such a setting, early anti-HLA Ab was never detected after BMT but was repeatedly detected after PBHSCT (flow cytometry, 6 of 18 versus 0 of 17 transplant recipients, P =.02; CDC, 4 of 23 versus 0 of 26 transplant recipients, P =.04). Importantly, the PBHSCT-associated increase in anti-HLA Ab detection was observed despite a reduction in the median number of platelet-transfusion episodes per patient in PBHSC transplant versus BM transplant recipients (3 platelet-transfusion episodes [range, 1-21] in PBHSCT group vs 6 platelet-transfusion episodes [range, 3-33] in the BMT group; P =.02). In conclusion, this study strongly suggests that G-CSF-mobilized PBHSCT results in an increased incidence of circulating anti-HLA Abs and further confirms that the use of such a graft alters alloimmune Ab responses.     

Evaluation of area-based collagen scoring by nonlinear microscopy in chronic hepatitis C-induced liver fibrosis

In this paper we analyze a fibrosis scoring method based on measurement of the fibrillar collagen area from second harmonic generation (SHG) microscopy images of unstained histological slices from human liver biopsies. The study is conducted on a cohort of one hundred chronic hepatitis C patients with intermediate to strong Metavir and Ishak stages of liver fibrosis. We highlight a key parameter of our scoring method to discriminate between high and low fibrosis stages. Moreover, according to the intensity histograms of the SHG images and simple mathematical arguments, we show that our area-based method is equivalent to an intensity-based method, despite saturation of the images. Finally we propose an improvement of our scoring method using very simple image processing tools.OCIS codes: (180.4315) Nonlinear microscopy, (170.1610) Clinical applications, (170.3880) Medical and biological imaging, (170.4580) Optical diagnostics for medicine, (110.2960) Image analysis