Clinical issues in the care of critically ill diabetic patients

Diabetes does not influence selected clinical outcomes in critically ill burn patients

The purpose of this study was to evaluate glucose control and clinical outcomes in diabetic burn intensive care unit (ICU) patients. The authors reviewed 462 civilian patients admitted to the burn ICU over 4 years. Exclusion criteria were age <18 years, admission because of skin infection, incomplete records, and military patients. Subjects were labeled as diabetic if they had a diagnosis of diabetes documented in their medical records. Otherwise, they were labeled as nondiabetic. Diabetic patients (n = 57) were compared with nondiabetic patients (n = 405). Admission glucose levels were obtained from chemistries. Point-of-care devices provided the remaining glucose values. While in the burn ICU, hyperglycemia for all patients was treated using intensive insulin therapy with a target blood glucose level of 80 to 110 mg/dl. Mann-Whitney U test, χ test, and multivariate regressions were used for statistical analysis (P ≤ .05). Diabetic patients were older (60 ± 15 vs 44 ± 17 years) with higher admission glucose (196 ± 81 vs 133 ± 52 mg/dl), mean glucose (147 ± 37 vs 122 ± 24 mg/dl), glucose variability (30 ± 11 vs 22 ± 11%), and fewer ICU-free days (18 ± 12 vs 20 ± 11). After multivariate regression analyses, age, injury severity score, TBSA, admission glucose, and mean glucose significantly affected the number of ventilator-free days, ICU-free days, and hospital-free days. Glucose variability was associated with hospital-free days only. Age, injury severity score, and TBSA significantly influenced mortality, whereas a preexisting diagnosis of diabetes was not associated with any clinical outcomes. Admission blood glucose is higher, and blood glucose is more difficult to control in diabetic burn ICU patients. A preexisting diagnosis of diabetes does not influence clinical outcomes in critically ill burn patients.

Diabetic polyneuropathy is associated with respiratory muscle impairment in type 2 diabetes

AIMS/HYPOTHESIS

Diabetes has a major negative effect on intensive care unit outcome. This has been partly attributed to impaired respiratory neuromuscular function. However, data on respiratory neuromuscular involvement in diabetes are lacking. This study therefore aimed to assess respiratory neuromuscular function related to diabetic polyneuropathy in patients with type 2 diabetes.

METHODS

Respiratory neuromuscular function was assessed by the use of volitional tests and twitch mouth (TwPmo) and twitch transdiaphragmatic (TwPdi) pressures during non-volitional bilateral anterior magnetic phrenic nerve stimulation in 21 male type 2 diabetic patients without pulmonary disease and in 23 healthy, well-matched controls (forced expiratory volume in 1 s 103 +/- 11 vs 103 +/- 12% predicted; p = 0.9).

RESULTS

Both volitionally assessed maximal inspiratory and expiratory mouth pressures, and sniff nasal and transdiaphragmatic pressures were comparable between diabetic patients and controls (p > 0.1 for all). TwPmo was reduced in diabetic patients compared with controls (1.3 +/- 0.5 vs 1.0 +/- 0.4 kPa; p = 0.04), while TwPdi was comparable (1.7 +/- 0.5 vs 1.6 +/- 0.7 kPa; p = 0.6). Following subgroup analysis, patients with no or mild polyneuropathy (n = 10) as assessed by neurological disability scoring had normal respiratory neuromuscular function, whereas patients with moderate or severe polyneuropathy (n = 11) presented with markedly impaired respiratory neuromuscular function as indicated by TwPmo (1.3 +/- 0.4 vs 0.8 +/- 0.3 kPa; p = 0.01) and TwPdi (1.9 +/- 0.6 vs 1.1 +/- 0.4 kPa; p < 0.01).

CONCLUSIONS/INTERPRETATION

With regard to volitional tests, diabetes does not affect respiratory neuromuscular function. In contrast, the application of non-volitional phrenic nerve stimulation provides strong evidence that diabetic polyneuropathy, as simply assessed by neurological disability scoring, is associated with substantially impaired respiratory neuromuscular function in type 2 diabetic patients.

The effects of induced diabetes and cutaneous Leishmania infection on the pharmacokinetics of antimony in hamsters

Patients with certain diseases appear to be at greater risk of developing adverse drug interactions, either because of the disease state itself or the drugs used to treat it. The effects of streptozotocin-induced diabetes and/or cutaneous Leishmania major infection on the pharmacokinetics of antimony (SbV) have now been investigated, in hamsters treated with sodium stibogluconate (Pentostam). The animals were randomly divided into five groups, each of 20 hamsters, known as D (for diabetes without leishmaniasis), DL (diabetes induced prior to the leishmaniasis), L (leishmaniasis without diabetes), LD (diabetes induced after leishmanial infection) and C (the control group, of animals with neither diabetes nor leishmaniasis). After its diabetes and/or leishmaniasis (if any) was established, each animal was given an intramuscular dose of sodium stibogluconate (80 mg/kg) each day for 3 weeks. Blood samples were collected after the first or last doses, to allow the pharmacokinetic parameters of SbV after single and multiple dosing to be compared. Although the between-dose interval (24 h) was more than 10 times longer than the terminal elimination rate constant (t1/2) at steady state, there was a significant increase in the mean peak SbV concentration (Cmax), as the result of multiple dosing, in all five groups (P<0.001 for each). The hamsters with diabetes showed the least accumulation of SbV in their blood, whether or not they were infected with L. major. In the non-diabetic animals of groups L and C, the apparent total clearance of SbV (CL/F) was decreased by multiple dosing, being, respectively, 34.5% and 23.0% lower after the 21st dose than after the first. An increase in urine volume was the reason for the significant increase in CL/F in group D (P<0.001), and this offset the decrease in CL/F seen in the L group, resulting in no change in CL/F in the animals of the DL group. Three weeks of antileishmanial treatment produced no significant reductions in the leishmanial lesions on the parasite-inoculated foot-pads of the hamsters in the L or DL groups but such reductions were detected in the animals of the LD group (P<0.001). In conclusion, it appears that the administration of SbV over a few weeks may cause renal toxicity and, in clinical use, should therefore be accompanied by the regular monitoring of renal function. A cautious increase in SbV dosing may be necessary for the effective treatment of L. major (and perhaps other species of Leishmania) in diabetic patients.

Nurses' rationale for blood glucose monitoring in critical care

Morbidity and mortality in a critical care environment is improved when there is tight control of blood glucose. This study aimed to explore nurses' rationale for blood glucose monitoring in a critical care setting. An exploratory qualitative design was utilized in one acute division of a large NHS Trust in Scotland. Volunteers were sought by letter and through posters in the clinical area. Five staff nurses from two critical care areas volunteered to take part in one-to-one interviews that were tape-recorded. All transcripts were analysed using content analysis. Nurses described differing perspectives on blood glucose monitoring. Nurses did not know the blood glucose level that defines hyperglycaemia, a knowledge gap which impacts on care intervention. Three sisters from the wards were interviewed to determine their perceptions of the reasons for the poor response rate. They identified several issues thought to impact on staff volunteering for research.