Apnoea depression

As the prevalence of obesity increases worldwide, so does the prevalence of associated co-morbidities type-2 diabetes, chronic obstructive sleep apnoea, cardiovascular disease (hyper-tension, coronary artery disease and congestive heart failure, stroke and peripheral vascular disease), fatty liver disease, various malignancies (Table 7.2), gallstones, subfertility, musculo-skeletal problems and depression. 

Adverse effects include respiratory depression (death from hypoventilation), dependence, apnoea, muscle rigidity, bradycardia, arrhythmia, chest pain, GI symptoms, haemoptysis, abdominal pain, headache, sorrmolence, confusion and hallucinations. 

It is indicated in all types of depression, nocturnal enuresis, intractable chronic pain, narcolepsy, chorea, cachexia, mood disturbances and sleep apnoea syndrome. 

Desflurane does not have a marked bronchodilator effect and in cigarette smokers it is associated with significant bronchoconstriction. In clinical practice, both humidification of inspired gases and opioids are thought to reduce airway irritability but even at moderate concentrations (2 MAC), desflurane is more likely to cause coughing than sevoflurane. In common with other volatile agents, desflurane causes dose-related respiratory depression. Tidal volume is reduced and respiratory rate increases, initially. As inspired concentrations of desflurane increase, the trend is to hypoventilation and hypercardia and apnoea is to be expected at concentrations of 1.5 MAC or greater. 

Enflurane is a potent respiratory depressant and apnoea may occur at inspired... 

Thiopentone has a potent dose-dependent, depressant effect on both respiratory rate and depth and depresses the sensitivity of the respiratory centre to carbon dioxide. A short period of apnoea is common, frequently preceded by a few deep breaths. Respiratory depression is influenced by premedication and is more pronounced in the presence of opioids and in patients with chronic obstructive pulmonary disease. 

Respiratory depression and duration of apnoea are of a lesser magnitude with methohexitone than with thiopentone. 

Naloxone is being used to reverse the potentially lethal respiratory depression caused by neurolept analgesia or opioid overdose. Among other pharmacological effects, naloxone antagonizes the blood pressure drop in various forms of shock [29-32], reverses neonatal hypoxic apnoea [26], counteracts chronic idiopathic constipation [34], reduces the food intake in humans [35, 36] and shows beneficial effects in CNS injuries [37]. 

Benzodiazepines can cause respiratory depression and apnoea especially in the elderly and in patients with respiratory insufficiency. The combination of an opioid and a benzodiazepine is... 

Interactions. All potentiate the effects of alcohol and other central depressants, and all are likely to exacerbate breathing difficulties where this is already compromised, e.g. in obstructive sleep apnoea. 

Insomnia is sleep disturbance and can be manifest as difficulty falling asleep, poor quality of sleep or premature awakening. Insomnia can be secondary to other conditions, for example anxiety or depression. Other causes are factors such as stress and excessive noise, jet lag, shift work, physical illness and pain, stimulants (coffee and tea), sleep apnoea or poor habits at bedtime. 

Respiratory insufficiency and prolonged apnoea occurred in a patient on two occasions while receiving cyclophosphamide and undergoing anaesthesia during which suxamethonium (succinylcholine) and tubocurarine were used. Plasma cholinesterase levels were found to be low. Anaesthesia without the suxamethonium was uneventful. Seven out of 8 patients subsequently examined also showed depressed plasma cholinesterase levels while taking cyclophosphamide. ... 

A manic depressive woman taking lithium carbonate with a lithium level of 1.2 mmol/L, underwent surgery and was given thiopental, 310 mg of suxamethonium (succinylcholine) over a period of 2 hours, and 500 mierograms of pancuronium. Prolonged neuromuscular blockade with apnoea occurred. ... 

Although acetazolamide can be used to treat acute mountain sickness at very high altitudes, a case report su ests that it may potentiate the respiratory depressant effects of benzodiazepines such as triazolam. Acetazolamide did not improve symptoms of sleep apnoea worsened by flurazepam. 

RESPIRATORY Chronic methadone maintenance therapy in a child with acute myeloid leukaemia who developed chemotherapy-induced renal insufficiency likely led to inadequate clearance of methadone and methadone-induced respiratory depression and central sleep apnoea [47" ]. 

In humans, the product produces hyperpnoea on administration and apnoea following overdose. It also produces marked depression in cardiopulmonary function in humans and in other animals.There are no reports of adverse reactions in humans following accidental self-injection or through any other routes of exposure and Salfan has largely been replaced by other injectable anaesthetics and notably by propofol (Chapter 5). 

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