Clinical complications of obesity

Respiratory mechanics of patients with morbid obesity

OBJECTIVE

To evaluate the different components of the resistance of the respiratory system, respiratory muscle strength and to investigate the occurrence of expiratory flow limitation (EFL) in patients with morbid obesity (MO) when seated.

METHODS

The sample was composed of MO (BMI≥40 kg/m2) and non-obese individuals (NO) with a BMI between 18 and 30 kg/m2. The protocol consisted of the anthropometric assessment and the following measures of respiratory function: spirometry, maximal inspiratory and expiratory pressures (MIP and MEP, respectively) and impulse oscillometry. The group comparison was performed using T-test for unpaired samples. The correlations were evaluated by the Pearson test with a significance level of 5%.

RESULTS

Fifty MO (age 40±10.4 years, 1.64±0.09 m, 138.8±33.6 kg and 50.7±8.9 kg/m2), and 30 NO (age 37.6±11.5 years, 1.67±0.09 m, 65.2±10.3 kg and 23.2±22 kg/m2) were evaluated. The MO showed higher values of total, peripheral, airways, tissue and central resistance when compared to the NO. No patient showed EFL. The waist circumference was associated with spirometric variables, MIP, and MEP. The waist-to-hip ratio was correlated to respiratory mechanics and spirometric variables, MIP, and MEP.

CONCLUSION

Morbidly obese patients with no obstructive spirometric pattern show increased total, airway, peripheral, and tissue respiratory system resistance when compared to nonobese. These individuals, however, do not present with expiratory flow limitation and reduced respiratory muscles strength.

The effects of the metabolic syndrome on coronary artery bypass grafting surgery

Background

The metabolic syndrome (MS) is a clustering of factors that are associated with increased cardiovascular risk. A low-grade inflammatory process acts as the underlying pathophysiology, which suggests that the MS may have a detrimental effect on coronary interventions, including coronary artery bypass grafting (CABG) surgery performed with cardiopulmonary bypass (CPB). We aimed to evaluate the effect of the MS on morbidity and mortality rates in the early postoperative period in patients undergoing CABG.

Methods

We prospectively included 152 patients (109 males and 43 females; mean age 60.1 ± 8.6 years) who underwent elective CABG on CPB between January and September 2011. Early postoperative morbidity and mortality rates were compared between subjects with and without the MS. Diagnosis of the MS was based on the American National Cholesterol Education Program Adult Treatment Panel III (NCEP ATP III) criteria.

Results

Of the study group, 64 patients (42%) had the MS. The two groups were similar in age and gender. In the postoperative period, rates of atrial fibrillation, wound infection, pulmonary complications, and lengths of intubation, hospitalisation and intensive care unit stay were significantly higher in MS patients (p < 0.01). The MS was significantly associated with wound infection (OR 6.64, 95% CI: 1.72–25.75), pulmonary complications (OR 6.44, 95% CI: 1.58–26.33), arrhythmia (OR 5.47, 95% CI: 1.50–19.97) and prolonged intubation (OR 1.17, 95% CI: 1.05–1.32). The mortality rate was 3.1% in the MS group and 1.1% in the non-MS group, with no significant difference (p > 0.05).

Conclusion

The MS was associated with a higher rate of early postoperative morbidity following CABG, without having a significant effect on the mortality rate.

Diabetes and diet in pregnancy

The mean additional energy requirement for pregnancy has been calculated at 285 kcal daily and it reflects the energy needs for production of the fetoplacental unit and for the maternal physiological adaptations to pregnancy. In practice there is considerable variation in energy requirement due to alterations in maternal energy expenditure. Optimal energy intakes are dictated also by the pre-pregnancy maternal weight. The outcome of pregnancy is improved in the underweight mother by an intake which produces a weight gain in pregnancy of approximately 14 kg, whereas a rise of only 7 kg may be optimal for the obese mother. Obesity with or without diabetes is associated with macrosomia and other problems and it is sensible to attempt to limit weight gain in pregnancy at a time when maternal motivation is high. Diabetes in pregnancy may arise in patients with pre-existing NIDDM or IDDM, but more commonly it is diagnosed for the first time during pregnancy and it usually disappears after delivery (gestational diabetes). Recent evidence suggests that gestational diabetes has a strong genetic component and is usually NIDDM precipitated early in life by the pregnancy. Both gestational diabetes and NIDDM are characterized by insulin deficiency and by insulin resistance. Long-term follow-up studies have demonstrated that NIDDM or impaired glucose tolerance develop in later life in 50-70% of women with previous gestational diabetes. The adverse effects of pregnancy on the mother with pre-existing diabetes may be minimized by good diabetic control as may be adverse effects on the fetus and neonate of diabetes in the mother. An increased incidence of fetal malformations persists in pregnancies with pre-existing maternal diabetes. Diabetes of any form may be associated with neonatal hypoglycaemia. The aim of therapy is to produce maternal normoglycaemia throughout pregnancy by dietary measures and insulin treatment if required. Women with pre-existing diabetes should tighten their blood glucose control from before conception. Optimization of insulin therapy and diet are required for IDDM and most NIDDM women will require insulin treatment in pregnancy. Gestational diabetics require diet and possibly insulin. Most pregnancies now proceed to term.