Biomedical subjects

H P Bandla

Publications and source records attributed to H P Bandla.

5 recordsLinked to original sources

PubMed2000

Dynamic changes in EEG spectra during obstructive apnea in children.

Children are less likely to demonstrate EEG arousal during obstructive sleep apnea (OSA) than adults. We hypothesized that changes in spectral EEG characteristics occur during REM-associated OSA in the absence of arousal. Eight snoring children underwent overnight polysomnography. OSA events during REM periods not associated with EEG or behavioral arousal were identified. EEG signals from C3A2 and C4A1 leads corresponding to 1) < or =10-sec epochs preceding OSA (PRE), 2) the obstructed period (OSA), and 3) < or =10-sec epochs following airflow resumption (POST) were subjected to fast Fourier transform (FFT) routines. Seventy-two isolated OSA, and 14 clusters of > 4 OSA events were analyzed. In single OSA, delta OSA amplitude was lower than in PRE (P < 0.01) and in POST (P < 0.001). Furthermore, POST delta amplitude was higher than PRE (P < 0.01). In contrast, in OSA clusters, the dynamic differences in delta amplitude disappeared after the second OSA. Reciprocal increases and decreases occurred for the theta frequency domain during OSA and post-OSA, while sigma and beta frequency power did not change. We conclude that during isolated OSA episodes without arousal, significant decreases in power selectively occur for delta frequency, and are followed by a rebound increase upon termination of apnea. The delta changes are progressively attenuated during repeated OSA. We postulate that delta changes may reflect ongoing adaptations in sleep pressure which are necessary to relieve the respiratory compromise, and may represent subtle evidence for arousal and consequent sleep fragmentation in children with OSAS.

Child↗

PubMed1999

Protein kinase C modulates ventilatory patterning in the developing rat.

Protein kinase C (PKC) mediates important components of signal transduction pathways underlying neuronal excitability and modulates respiratory timing mechanisms in adult rats. To determine ventilatory effects of systemic PKC inhibition during development, whole-body plethysmographic recordings were conducted in 2-3-d (n = 11), 5-6-d (n = 19), 10-12-d (n = 14), and 20-21-d-old (n = 14) rat pups after treatment with vehicle and Ro 32-0432 (100 mg/kg, intraperitoneally). Ro 32-0432 decreased minute ventilation (V E) by 51.0 +/- 5.5% (mean +/- SEM) in youngest pups (p < 0.01) but only 19.1 +/- 6.8% in 20-21-d-old pups (p < 0.01). V E decreases were always due to frequency reductions with tidal volume (VT) remaining unaffected. Respiratory rate decreases primarily resulted from marked expiratory time (TE) prolongations being more pronounced in 2-3-d-old (115.5 +/- 28.9%) compared with 20-21-d old (36.6 +/- 10.9%; p < 0.002 analysis of variance [ANOVA] ). Expression of the PKC isoforms alpha, beta, gamma, delta, iota, and mu was further examined in brainstem and cortex by immunoblotting and revealed different patterns with postnatal age and location. We conclude that endogenous PKC inhibition elicits age-dependent ventilatory reductions which primarily affect timing mechanisms rather than changes in volume drive. This effect on ventilation abates with increasing postnatal age suggesting that the neural substrate mediating overall respiratory output may be more critically dependent on PKC activity in the immature animal.

Aging↗

PubMed1999

Pulmonary risk factors compromising postoperative recovery after surgical repair for congenital heart disease.

STUDY OBJECTIVES: To identify pulmonary risk factors associated with prolonged ICU stay in young children (< or = 2 years) undergoing surgical repair for congenital heart disease (CHD). DESIGN: Retrospective case series analysis. SETTING: Tertiary-care facility. PATIENTS: Clinical records of 134 consecutive patients aged < or = 2 years undergoing cardiac surgery for CHD were reviewed, and 37 were excluded according to inclusion criteria. Thus, 97 patients were allocated to two groups based on the duration of ICU stay: < or = 7 days (group 1, n = 57), and > 7 days (group 2, n = 40). RESULTS: Mean ICU duration for groups 1 and 2 was 3.0 +/- 0.4 days and 28.1 +/- 4.4 days, respectively (p < 0.001). In group 1, there were three extubation failures, whereas 41 extubation failures occurred in group 2 (p < 0.0001). A total of 22 patients (4 in group 1 and 18 in group 2) developed noninfectious pulmonary complications, such as airway problems, including extrinsic airway compression and tracheobronchomalacia (n = 6); pulmonary hypertension (n = 5); phrenic nerve palsy (n = 7); and pleural effusion (n = 8). These 22 patients (23%) contributed to the majority of total ventilator days (67%) as well as ICU stay (61%). CONCLUSIONS: Pulmonary complications in general, and central airway problems in particular, are a frequent cause for delayed recovery following cardiac surgery in young children.

Cardiac Surgical Procedures↗

PubMed1999

Lipoid pneumonia: a silent complication of mineral oil aspiration.

INTRODUCTION: Chronic constipation is a common symptom in pediatrics, and physicians often use mineral oil to treat chronic constipation in children. Mineral oil, a hydrocarbon, may not elicit a normal protective cough reflex and may impair mucociliary transport. These effects can increase the likelihood of its aspiration and subsequent impaired clearance from the respiratory tract. We report a case of a child with neurodevelopmental delay with chronic constipation and a history of chronic mineral oil ingestion presenting as asymptomatic exogenous lipoid pneumonia (ELP). CASE HISTORY: A 6-year-old white boy with a history of developmental delay was found to have an infiltrate in his right upper lobe on a chest radiograph obtained during evaluation for thoracic scoliosis. The patient had a long history of constipation with daily use of mineral oil. He was fed by mouth and had occasional episodes of coughing and choking during feeding. He was asymptomatic at presentation and physical examination was unremarkable. The patient was advised to stop administration of the mineral oil and was treated empirically with antibiotics during a 3-month period. At follow-up examination the patient continued to be asymptomatic, with the radiologic persistence of the infiltrate. Diagnosis of lipoid pneumonia was made by diagnostic bronchoscopy with bronchoalveolar lavage (BAL). The exogenous origin of the lipid in the BAL fluid was confirmed by gas chromatography/mass spectrometry. DISCUSSION: The clinical presentation of ELP is nonspecific and ranges from the totally asymptomatic patient with incidental radiologic finding, like our patient, to the patient with acute or chronic symptoms attributable to pneumonia, pulmonary fibrosis, or cor pulmonale. Bronchoscopy with BAL can be successful in establishing the diagnosis of ELP by demonstration of a high lipid-laden macrophage index. Treatment of ELP in children is generally supportive, with the symptoms and roentgenographic abnormalities resolving within months after stopping the use of mineral oil. CONCLUSION: Lipoid pneumonia as a result of mineral oil aspiration still occurs in the pediatric population. It can mimic other diseases because of its nonspecific clinical presentation and radiographic signs. In patients with swallowing dysfunction and pneumonia, a history of mineral oil use should be obtained and a diagnosis of ELP should be considered in the differential diagnoses if mineral oil use has occurred. Our case points to the need for increased awareness by the general pediatricians of the potential hazards of mineral oil use for chronic constipation.

Bronchoalveolar Lavage↗

PubMed1997

Laryngeal mask airway facilitated fibreoptic bronchoscopy in infants.

PURPOSE: To assess the efficacy of the laryngeal mask airway (LMA) for fibreoptic bronchoscopy (FOB) and bronchoalveolar lavage (BAL) in infants. METHODS: Observations were made in 19 consecutive infants undergoing FOB under general anaesthesia (GA) plus topical local anaesthesia. Anaesthesia was induced with N2O, O2, and halothane or sevoflurane except in two patients who received propofol and one who received thiopentone. Anaesthesia was maintained with oxygen and either sevoflurane, halothane, desflurane, or propofol infusion. No neuromuscular blockers were used. Size #1 or #2 LMAs were used through which a 3.5 mm fibreoptic bronchoscope was introduced. ECG, noninvasive blood pressure, pulse oximetry and, PETCO2 were measured. Intra- and post-procedural complications were recorded. RESULTS: Mean age was 6 months; mean weight was 6.6 kg. Chronic wheezing was the indication for FOB in eight patients. Minor complications occurred in five patients: difficult LMA placement in one patient required changing size from #2 to #1; two patients had laryngospasm and bronchospasm that resolved with deepened anaesthesia and nebulised bronchodilator; one patient had transient arterial O2 desaturation, responding to increased FIO2, and one patient required tracheal intubation because ventilation via LMA became inadequate. CONCLUSION: The minor complications observed were similar to other series and did not result in morbidity or mortality. We feel that GA via LMA facilitates safe FOB in infants. It affords excellent airway management, a quiet patient, and passage of a large fibreoptic bronchoscope for better imaging and suction channel required for BAL.

Anesthesia↗