When a valid indication for vacuum-assisted birth exists, the relevant obstetric variables should be identified and carefully assessed to determine whether vacuum-assisted birth is appropriate and safe under the clinical circumstances and for the level of experience of the operator. This important decision-making process is considered in Chapters 2 and 3 of the book. This chapter focuses on a few selected technical matters that should, if followed, improve the efficacy and reduce the risk of vacuum-assisted birth.

At first glance there seems little point in studying the aetiology of PTI. The very definition includes the cause. As Brett and Ostroff (1985) have pointed out, the hypothesis that a unique pattern of symptoms is caused by the experience of extremely stressful events is central to the inclusion of PTSD in the DSM. The threat and feelings of helplessness and vulnerability are thought to be uniquely destabilising of the victim's previous function. PTSD is defined as being the consequence of a traumatic event. In DSM-IV (American Psychiatric Association, 1994), PTSD is one of the few disorders for which the atheoretical approach is abandoned and the definition includes presumed aetiology. It is stated that ‘the essential feature of PTSD is the development of characteristic symptoms following exposure to an extreme traumatic stressor’. In the differential diagnosis section it is recorded that the stressor must be of an extreme (i.e. life-threatening) nature. This is in keeping with the definition in ICD-io (World Health Organisation, 1992).

It seems clear that the aetiology of PTI is connected with trauma, even though Scott (Scott and Stradling, 1994) has suggested that PTSD can occur in the absence of extreme trauma, and there has been serious debate about the necessity or otherwise of the stressor criterion (March, 1993). Breslau and Davis (1987a) have pointed out that there is ‘insufficient data to show that the set of symptoms characteristic of PTSD is strongly and uniquely associated with extraordinary stressors’.

It is the author's contention that this chapter is of great importance. With no apologies for repetition, it is emphasised that:

Although the term PTSD was put forward only in the late seventies and confirmed in 1980, there is no suggestion that the concept that exposure to major trauma can cause mental illness is new. It has long been recognised that trauma can be followed by mental illness. In an editorial addressing a different aspect of controversy surrounding PTSD, Andreasen (1995) reminds us that there was recognition of PTI in DSM-I but that at that time it was ‘conceptualised and defined psychologically’, that it was seen as being ‘by definition acute and reversible’ as it was included in ‘transient situational personality disorders’, and that no characteristic symptoms were specified. She sees the creation of PTSD as being required to meet the need of a generation of Vietnam veterans, many of whom had severe stress syndromes, and as it being a ‘general name’ because of the similarity of the syndrome across various stressors.

Essentially, DSM-I recognised that trauma could produce acute illness and implicitly indicated psychological causation. However, it did not describe a specific syndrome and saw chronic illness as representing precipitation or aggravation of a constitutional or potential disorder rather than a specific response to trauma.

Before we can examine normal reactions to trauma, it is necessary to come to some understanding of what is and is not normal. This may seem pedantic or simplistic, but it is not as simple as it seems.

The Oxford English Dictionary contains a large number of definitions of the word normal. Some are specific to physics or chemistry and are not relevant. Others include:

• the usual state or condition

• constituting, conforming to, not deviating or differing from, the common type or standard; regular, usual

• a normal variety of anything; that which, or a person who, is healthy and is not impaired in any way.

It is a little depressing to see that even The Oxford English Dictionary uses the word normal in the definition of the word normal. It seems that there are two relevant definitions of normal. One refers to the frequency of occurrence of the matter under study, that it is or is not the usual or common state. The other refers to an absence of disease. The two are not synonymous. For example, acne is probably statistically normal in adolescence but is not a healthy-normal. More dramatically, the statistically normal response to ingestion of an inoculum of Vibrio cholerae is probably to develop cholera.

It is fairly easy to define a concept of statistical normality. For example, the modal response might be considered to be the statistical norm.

Thus far this book has been intended to present the case for the importance and relevance of PTI in general and PTSD in particular. The aim of this chapter is to present some personal ideas and questions, and to try to consider the future direction of work on the psychological effects of trauma and the postulated physical effects in the brain of psychological trauma. It is unashamedly a personal view and is intentionally written without references, although hopefully the sources of most of the questions and problems have been detailed in the text thus far.

Trauma and mental illness are a subject which has inevitably preoccupied me over the years because of my employment. As a trainee psychiatrist in the army it seemed inevitable that I would be confronted with the history of battle shock and the future of combat stress in the anticipated battlefields of North West Europe. In the event the first case of PTI which I met was from one of the sad series of airline crashes which have come to be known by the name of the relevant city, or airfield, or flight number. What it taught me was the power of trauma and the intransigence of avoidance symptoms. A series of individual cases from Northern Ireland and from the Falklands taught me about PTI and then about PTSD. What they taught me was not so much the uniformity and the commonality of post-traumatic illnesses, but the variety of post-traumatic responses.

In this chapter we will look at the medicolegal connotations of PTI. Where there is a need specifically to address legal practice, the focus will be quite clearly upon the interaction of PTI and law in England and Wales. Aspects of American law have been addressed widely elsewhere, for example by Sparr (Sparr and Boehnlein, 1990) and others. Indeed, almost all of the work concerning PTI and criminal law, as well as much of that concerning civil law, comes from America. There are a number of useful books and pamphlets which specifically address the legal side of the psychiatric injury issues (Napier and Wheat, 1995) (Law Commission 1995) in England and Wales, or in areas with similar basis of law (Mullany and Handford, 1993). An attempt will be made in this chapter to examine both criminal and civil legal issues from the point of view of the expert clinician.

Probably more than any other form of mental illness, PTI is associated with medicolegal issues. It seems that in almost every case of PTI, be it PTSD or another condition, there is at least the potential for some form of legal or quasilegal consequence. There are a number of obvious areas of possible concern:

• PTI may be presented as a defence or mitigating factor in criminal cases

• PTI may be a consequence of criminal behaviour

• PTI may be a consequence of a civil wrong.

By definition, post-traumatic illness follows some sort of trauma. It has been recognised for many years that illness can follow trauma. However, what constitutes trauma is far from clear. In particular the type or extent of trauma necessary to cause PTSD is an issue which has been argued fiercely since PTSD was defined in DSM-III.

The whole concept of PTI is that it would not have occurred if it were not for a preceding trauma. The evidence is that there certainly is an excess of mental illness following major traumatic events, and this suggestion is not generally challenged.

The concept of PTSD in particular, on the other hand, demands more than that it be an illness which occurs in response to traumatic events. In addition it has to be an illness which occurs only following certain particular classes or severity of traumata, and which does not ever occur in the absence of such events. Is this backed by empirical evidence?

This chapter will look at the standing of illness following trauma, will examine the evidence for post-traumatic mental health problems, and will examine in detail the stressors which cause PTSD and the evidence that there is a specific pattern of illness which follows major trauma but which does not occur in other situations. The significance and meaning of the concept of qualifying events will be discussed. The changing status and definition of the stressor criterion in DSM will be considered and examined, as well as compared with ICD. Finally, the argument for the abolition of the stressor criterion will be examined.

This book is intended to be a brief but comprehensive textbook of the mental disorders or difficulties which can follow trauma and traumatic events. It is hard to argue with the suggestion that disasters, catastrophes, violence and traumatic incidents are all too common in modern society. Nobody would seriously suggest that previous centuries were idyllic peaceful times; natural disasters have always occurred. However, the sheer scale of the efforts which we have made to kill and maim each other this century has far outclassed the equally brutal but probably far less efficient activities of our forebears. Increased speed has its effect. Not only do we move around at greater and greater speeds, with the results of accidents being more horrific, but information moves around the world at faster and faster rates so that communication may be almost instantaneous. Some of the particular problems associated with the impact of trauma on the psyche could not have happened until the last decade. Only now can a mother sit at home and watch live footage of a shipwreck in which she believes that her son has drowned.

The frequency and diversity of traumatic events which may affect one person or thousands are such that the consequences of trauma will probably impinge upon all of us at some time. They will certainly impact upon the work of health and other service workers in general and mental health and social work professionals in particular.

There is a definite paucity of empirical data about the treatment and the outcome of PTI other than PTSD and acute stress disorder. In acute stress disorder the data are sparse and mostly based upon either intervention in combat stress disorder, or on uncontrolled trials or case data.

Even in the most closely studied area, that of PTSD, there is insufficient evidence to say that there is a single specific treatment strategy which is the most appropriate to be used in every case or in the typical case of PTSD. In the same way, there is considerable controversy about the prognosis in PTSD.

ICD-io suggests that PTSD is essentially of good prognosis (World Health Organisation, 1992) when it says ‘the course is fluctuating but recovery can be expected in the majority of cases’.

However, it also points out that ‘in a small proportion of patients the condition may show a chronic course over many years and a transition to an enduring personality change’. It is suggested, therefore, that PTSD may precede a type of personality change which is ‘a chronic, irreversible sequel of stress disorder’. The notes to the specific diagnosis in ICD-io indicate that such a change should only be diagnosed following extreme and prolonged traumatic events and not following brief life-threatening experiences such as road traffic accidents. The diagnostic guidelines are somewhat vague. The prognosis for this condition, which is not present in DSM-IV but is akin to the concept of DESNOS (Worzel, 1992), is effectively of inevitable poor prognosis as it is necessary for the changes in personality to have been present for two years before the diagnosis can be made, and because it is described as ‘enduring’.

What is the purpose of diagnosis?

It is important to consider the reason for making a diagnosis. For many mental disorders the reasons for making a diagnosis are quite transparent. Diagnosis can be considered to serve three main purposes:

• to ease communication by allowing a shorthand way of describing a particular sort of problem or set of clinical findings

• to allow predictions to be made about likely course

• to allow rational treatment, management and allocation of services.

Even when the primary focus of concern is not service allocation, the making of a diagnosis usually has the same significance. For example, in a forensic psychiatric setting, the diagnosis of schizophrenia says something about the condition, the likely course, and the likely response to treatment. It does not, per se, say anything about responsibility for the particular act or omission under consideration or about the cause of the illness.

This is not the case in PTSD. The diagnosis itself defines aetiology. By the nature of the aetiologically significant events, this also usually identifies a person or organisation which is allegedly responsible for causing, or failing to prevent, the disorder. The diagnosis of PTSD not only provides a useful shorthand, makes predictions about course, and suggests likely management options, but it also acts as a key.

This key can provide access to a variety of doors and resources.

There is considerable interest in the prevention of PTI. Popular opinion and the involvement of the media mean that it has now become entirely routine, if not somehow mandatory, for officially sanctioned efforts to be put in place to prevent PTI. At the time of writing, the most recent example has perhaps been the tragic killing of children in a school in Dunblane. As usual, there were the immediate reports of the arrival of ‘trained counsellors’ to help the survivors and the bereaved to cope. In conversation recently researchers have commented upon the difficulties in conducting a controlled trial of counselling or psychological debriefing after disasters because of the reluctance of survivors to become part of the control groups. Everybody in the general population knows that disaster is followed by some form of counselling or intervention and they are wary about being left out. There is a widespread assumption that such intervention is at least helpful, if not essential.

However, as recently as 1994, Lundin has said ‘it is not quite clear that it is possible to prevent post traumatic stress disorder by means of early psychological support, counselling, or psychotherapeutic treatment’ (Lundin, 1994). However, despite this, he nevertheless expresses the view, which is no doubt held by many who work in the management or provision of health services, that there is a ‘basic human duty’ to try to do so.

As with so much else, the vast majority of the research into the epidemiology of post-traumatic illness has looked at post-traumatic stress disorder specifically. However, whereas the combat studies tend to concentrate solely on this, there are a number of civilian trauma-related and disaster-related studies which have looked at the incidence and prevalence of other conditions following trauma exposure.

There are generally three types of epidemiological study which have been carried out in post-traumatic research:

• those looking at patients presenting for treatment

• those looking at identified high-risk groups or at those otherwise selected

• genuine community studies of prevalence.

The last of these seems to be the most important and is the least common. It is unsurprising that community studies of a ‘new’ condition would be preceded by studies of complainants and of high-risk groups. However, there can be no doubt that the only way to estimate the real relevance and importance of the condition is to measure its prevalence in the general population. Such studies do now exist.

Kulka (Kulka et al., 1991) has commented upon the rapid expansion of epidemiological research from relatively small studies in clinical settings, via the congressionally mandated post-Vietnam studies, into population-based or ‘community’ studies. He points out that studies outwith treatment settings present both opportunities and potential hazards. He focuses upon the importance of the diagnostic methods and treatment design used.